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Dolutegravir (DTG) is primarily metabolized by uridine diphosphate glucuronosyltransferases, forming the pharmacologically inactive DTG glucuronide (DTG‐gluc). We described the dolutegravir metabolic ratio (DTG‐MR; DTG‐gluc AUC0–24h divided by DTG AUC0–24h) in 85 children with HIV aged 3 months to 18 years receiving DTG in the CHAPAS‐4 (ISRCTN22964075) and ODYSSEY (NCT02259127) trials. Additionally, we assessed the influence of age, body weight, nucleoside/nucleotide reverse transcriptase inhibitor (NRTI) backbone, rifampicin use and kidney function on DTG‐MR. The overall geometric mean (CV%) DTG‐MR was 0.054 (52%). Rifampicin use was the only significant factor associated with DTG‐MR (P < .001) in multiple linear regression. DTG‐MR geometric mean ratio was 1.81 (95% CI: 1.57–2.08) for children while on vs. off rifampicin. This study showed that overall DTG‐MR in children was similar to adults, unaffected by age or NRTI backbone, and increased with rifampicin co‐administration. These findings support future paediatric pharmacokinetic modelling and extrapolation from adult data. [ABSTRACT FROM AUTHOR]

Objective: To develop and implement a pilot educational program on genetic testing at the Tokai University School of Medicine with a public engagement approach through a local junior-high school outreach program. Methods: Seven medical students underwent 2 weeks of education and training to act as instructors for a one-day course on genetic testing for local junior-high school students. The one-day course comprised a lecture and an experimental lesson. The variation of UDP-glucuronosyltransferase 1A1 gene (UGT1A1) was selected as the teaching topic. A commercially available cultured human leukemia cell line was used as the source of human genomic DNA to circumvent the ethical concerns associated with obtaining samples from participants for genomic analysis. The medical students received instructions on the basics of conducting laboratory work and handling the equipment and reagents during the 2-week training. Results: The seven medical students completed the 2-week training. They then taught PCR and restriction enzyme experiments and the meaning of the results to junior-high school students. Conclusion: A pilot educational program on genetic testing with a local community outreach approach was successfully developed and implemented. [ABSTRACT FROM AUTHOR]

Yang Gou,1,2 Ping Wang,1,2 Wucheng Yang,1,2 Yimei Feng,1,2 Xiangui Peng,1,2 Hong Liu,1,2 Shuiqing Liu,1,2 Xi Zhang1,2 1Medical Center of Hematology, Xinqiao Hospital of Army Medical University, Chongqing, 400037, People’s Republic of China; 2Chongqing Key Laboratory of Hematology and Microenvironment, Chongqing, 400037, People’s Republic of ChinaCorrespondence: Hong Liu; Shuiqing Liu, Email 1241580141@qq.com; liushuiqing062@tmmu.edu.cnAbstract: Hereditary spherocytosis (HS) is the most common hereditary hemolytic disease with defects in red blood cells (RBC) membrane proteins caused by mutations in membrane protein genes, like SPTB, SPTA1 and ANK1. Gilbert syndrome (GS) is a disease characterized by a mild deficiency of uridine diphosphate-glucuronosyltransferase 1A1 (UGT1A1) enzyme activity and unconjugated hyperbilirubinemia, largely caused by UGT1A1 mutations. The two inherited diseases HS and GS are rarely occurred in the same patient and are easy to be misdiagnosed, resulting in excessive diagnosis and treatment. Here, we report a rare case of HS combined with GS due to mutations in the SPTB and UGT1A1 genes. A 50-year-old man who had an over 40-year history of jaundice was admitted to our hospital owing to fatigue and fever. His blood analysis showed low hemoglobin (74 g/L), high reticulocyte (23.5%) and high serum bilirubin (65 μmol/L); abdominal ultrasound revealed calculous cholecystitis and splenomegaly. Considering a possible diagnosis of hemolytic anemia, further examinations showed 42% spherocytes in blood smears and high erythroid lineage hyperplasia in bone marrow. Subsequently, 151 jaundice-related genes panel sequencing was done and results showed SPTB p.N1260fs and UGT1A1 p.G71R mutations. Then the patient was diagnosed with HS complicated with GS. Anti-infection and supportive treatments were providing to the patient, while infection removed, the hemoglobin recovered to normal, and no additional treatment was given. These findings of this report indicate that patients who are considered hemolytic anemia presenting with jaundice and anemia, genetic testing is a crucial method for the final diagnosis and bilirubin metabolic disease should also be concerned.Keywords: hereditary spherocytosis, Gilbert syndrome, SPTB, UGT1A1

Pregnancy is associated with various physiological changes that can significantly impact the disposition of drugs. To further the insight into how pregnancy affects the pharmacokinetics of drugs at different stages, clinical studies can be simulated using Physiologically Based Pharmacokinetic modelling. PBPK modelling of drugs metabolised by Phase I enzymes (CYPs) in pregnant population models had been reported in the past, while its use in Phase II (UGTs) is not known. In this study, based on the results of a recent meta-analysis, lamotrigine (UGT1A4) and raltegravir (UGT1A1) were selected as candidate drugs, and pregnancy-specific models were developed for both using the Simcyp v.21 simulator. A middle-out strategy was used where previously published drug parameters were adapted from a minimal to a full PBPK model to allow their application for the pregnancy population models using Simcyp PBPK software. Adapted models were successfully validated against observed clinical data both qualitatively (visual overlay of plasma concentrations on graphs) and quantitatively (calculating the predicted/observed ratios for AUC, Cmax and CL as well as statistical analysis using model prediction power metrics). They were then applied to predict the PKs of both drugs in pregnancy population models. The temporal changes in maternal enzymatic activities during gestation were modelled based on in vitro data reported in literature and default relationships encoded in the Simcyp platform for UGT1A1 and UGT1A4, respectively. Our study demonstrates the successful development and validation of a PBPK model for LTG and RTG in pregnancy population models. Future work with additional UGT1A4 substrate drugs using the proposed changes in UGT1A4 activity may enable validating the pregnancy population model and its subsequent use for the prospective prediction of PK.

Pregnancy is associated with various physiological changes that can significantly impact the disposition of drugs. To further the insight into how pregnancy affects the pharmacokinetics of drugs at different stages, clinical studies can be simulated using Physiologically Based Pharmacokinetic modelling. PBPK modelling of drugs metabolised by Phase I enzymes (CYPs) in pregnant population models had been reported in the past, while its use in Phase II (UGTs) is not known. In this study, based on the results of a recent meta-analysis, lamotrigine (UGT1A4) and raltegravir (UGT1A1) were selected as candidate drugs, and pregnancy-specific models were developed for both using the Simcyp v.21 simulator. A middle-out strategy was used where previously published drug parameters were adapted from a minimal to a full PBPK model to allow their application for the pregnancy population models using Simcyp PBPK software. Adapted models were successfully validated against observed clinical data both qualitatively (visual overlay of plasma concentrations on graphs) and quantitatively (calculating the predicted/observed ratios for AUC, Cmax and CL as well as statistical analysis using model prediction power metrics). They were then applied to predict the PKs of both drugs in pregnancy population models. The temporal changes in maternal enzymatic activities during gestation were modelled based on in vitro data reported in literature and default relationships encoded in the Simcyp platform for UGT1A1 and UGT1A4, respectively. Our study demonstrates the successful development and validation of a PBPK model for LTG and RTG in pregnancy population models. Future work with additional UGT1A4 substrate drugs using the proposed changes in UGT1A4 activity may enable validating the pregnancy population model and its subsequent use for the prospective prediction of PK. [ABSTRACT FROM AUTHOR]

Gene variants in the UGT1A1 gene are strongly associated with circulating bilirubin levels in several populations, as well as other variants of modest effect across the genome. However, the effects of such variants are unknown regarding the Native American ancestry of the admixed Latino population. Our objective was to assess the Native American genetic determinants of serum bilirubin in Chilean admixed adolescents using the local ancestry deconvolution approach. We measured total serum bilirubin levels in 707 adolescents of the Chilean Growth and Obesity Cohort Study (GOCS) and performed high-density genotyping using the Illumina-MEGA array (>1.7 million genotypes). We constructed a local ancestry reference panel with participants from the 1000 Genomes Project, the Human Genome Diversity Project, and our GOCS cohort. Then, we inferred and isolated haplotype tracts of Native American, European, or African origin to perform genome-wide association studies. In the whole cohort, the rs887829 variant and others near UGT1A1 were the unique signals achieving genome-wide statistical significance (b = 0.30; p = 3.34 × 10-57). After applying deconvolution methods, we found that significance is also maintained in Native American (b = 0.35; p = 3.29 × 10-17) and European (b = 0.28; p = 1.14 × 10-23) ancestry components. The rs887829 variant explained a higher percentage of the variance of bilirubin in the Native American (37.6%) compared to European ancestry (28.4%). In Native American ancestry, carriers of the TT genotype of this variant averaged 4-fold higher bilirubinemia compared to the CC genotype (p = 2.82 × 10-12). We showed for the first time that UGT1A1 variants are the primary determinant of bilirubin levels in Native American ancestry, confirming its pan-ethnic relevance. Our study illustrates the general value of the local ancestry deconvolution approach to assessing isolated ancestry effects in admixed populations. [ABSTRACT FROM AUTHOR]

Objective To investigate the clinical characteristics of 53 cases of congenital hyperbilirubinemia (Gilbert syndrome, Crigler-Najjar syndrome) caused by UGT1A1 gene mutation in Yunnan Province and the characteristics of UGT1A1 gene mutation. Methods 53 cases were selected from the Department of Gastroenterology of Kunming Children’ s Hospital from January 2017 to December 2022 and divided into Gilbert syndrome (GS) group and Crigler-Najjar-2 (GN-2)group. The clinical data and genetic test results of children with type I1 syndrome (CN-2 group)and the clinical manifestations, laboratory test results and gene polymorphisms of the children were retrospectively analyzed. Results Children from the ethnic minority had the higher incidence in both groups. The proportion of females in CN-2 group was higher than that in GS group. In terms of liver system, the levels of TBil and IDB in CN-2 group were higher than those in GS group, with statistical significance (all P values < 0.05). The liver structure in GS group was normal, while 3 patients in CN-2 group had the abnormal liver and biliary structure. In the extra-hepatic system, there were no abnormalities in blood system and glucose metabolism, abnormal blood lipids and thyroid function metabolism, vitamin D deficiency in GS group, vitamin A and D deficiency and vitamin E decreased in CN-2group. There were cardiac structural abnormalities in both groups, but the incidence of CN-2 group was higher than that of GS group. Among all the patients, the mutation frequency of c.1456T>G in exon 5 was the highest (32 cases, 60.37%), followed by c.1091C>T (14 cases, 60.37%). Exon 1, C.211g>A (6 cases, 11.32%), and C.1198a >C (4 cases, 7.55%). The frequency of c.1456T>G mutation in GS group and CN-2 group was 69.23% and 57.5%（9 and 23 cases), respectively, and there was no significant difference between the two groups (P > 0.05). Among the two groups, the second most frequent mutation was c.1091C>T (4 cases and 10 cases), and there was no statistical significance between the two groups (P > 0.05).The frequencies of UGT1A1 haplotypes 1、3 and 4 were statistically significant between GS group and CN-2 group (P < 0.05). There is no significant difference in gender and ethnic groups among the four major mutation forms of UGT1A1 (P > 0.05). Conclusion The clinical manifestations of the liver system and [ABSTRACT FROM AUTHOR]

Hepatic fibrosis is an important pathological manifestation of chronic schistosome infection. Patients with advanced schistosomiasis show varying degrees of abnormalities in liver fibrosis indicators and bilirubin metabolism. However, the relationship between hepatic fibrosis in schistosomiasis and dysregulated bilirubin metabolism remains unclear. In this study, we observed a positive correlation between total bilirubin levels and the levels of ALT, AST, LN, and CIV in patients with advanced schistosomiasis. Additionally, we established mouse models at different time points following S. japonicum infection. As the infection time increased, liver fibrosis escalated, while liver UGT1A1 consistently exhibited a low expression, indicating impaired glucuronidation of bilirubin metabolism in mice. In vitro experiments suggested that SEA may be a key inhibitor of hepatic UGT1A1 expression after schistosome infection. Furthermore, a high concentration of bilirubin activated the NF-κB signaling pathway in L-O2 cells in vitro. These findings suggested that the dysregulated glucuronidation of bilirubin caused by S. japonicum infection may play a significant role in schistosomiasis liver fibrosis through the NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Background: Benzo(a)pyrene (B[a]P) is the most widely concerned polycyclic aromatic hydrocarbons (PAHs), which metabolizes benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE) in vivo to produce carcinogenic effect on the body. Currently, there is limited research on the role of the variation of metabolic enzymes in this process. Methods: We carried out a study including 752 participants, measured the concentrations of 16 kinds PAHs in both particle and gaseous phases, urinary PAHs metabolites, leukocyte BPDE-DNA adduct and serum BPDE- Albumin (BPDE-Alb) adduct, and calculated daily intake dose (DID) to assess the cumulative exposure of PAHs. We conducted single nucleotide polymorphism sites (SNPs) of metabolic enzymes, explored the exposure–response relationship between the levels of exposure and BPDE adducts using multiple linear regression models. Result: Our results indicated that an interquartile range (IQR) increase in B[a]P, PAHs, BaPeq, 1-hydroxypyrene (1-OHP), 1-hydroxynaphthalene (1-OHNap) and 2-hydroxynaphthalene (2-OHNap) were associated with 26.53 %, 24.24 %, 28.15 %, 39.15 %, 12.85 % and 14.09 % increase in leukocyte BPDE-DNA adduct (all P 0.05). Besides, we also found the polymorphism of CYP1A1(Gly45Asp), CYP2C9 (Ile359Leu), and UGT1A1(downstream) may affect BPDE adducts level. Conclusion: Our results indicated that leukocyte BPDE-DNA adduct could better reflect the exposure to PAHs. Furthermore, the polymorphism of CYP1A1, CYP2C9 and UGT1A1affected the content of BPDE adducts.

Polymorphisms of the uridine-diphospho-glucuronosyltransferase 1A1 (UGT1A1) gene, hepatic solute carrier organic anion transporter 1B1/B3 (SLCO1B1/3) gene, and glutathione S-transferase (GST) gene have been associated with significant hyperbilirubinemia in some populations. This study aims to determine whether the variation of UGT1A1, SLCO1B1/3 and GST genes play an important role in neonatal hyperbilirubinemia in Turkish newborn infants.

Purpose Uridine diphosphate glucuronosyltransferase 1A isoform 1 (UGT1A1) is a crucial enzyme in bilirubin metabolism. Mutations in this gene cause prolonged unconjugated hyperbilirubinemia in infants. This study aimed to investigate the prevalence of UGT1A1 mutations and their association with prolonged, unexplained, and unconjugated hyperbilirubinemia in infants. Methods From July 2019 to March 2023, 74 infants with prolonged jaundice lasting >21 days were enrolled in this study. Diagnostic evaluations, including UGT1A1 mutation analysis, were performed to identify the underlying causes of hyperbilirubinemia. This retrospective review evaluated the incidence and types of mutations in UGT1A1. The clinical and laboratory findings were compared based on the specific mutations detected. Results Thirty-three infants agreed to UGT1A1 mutation analysis, and 30 (90.9%) were positive for UGT1A1 mutations. Single-nucleotide variants were detected in 20 (66. %) infants. The remaining 10 (33.3%) infants had multiple variants. No significant demographic differences were observed between the group that underwent UGT1A1 mutation analysis and the group that did not. Among the identified genetic variants, c.211G>A (46.5%) and c.-3275T>G (30.2%) were the two most common variants. The other variants had the following percentages: c.1456T>G, c.-64G>C, and c.1091C>T (4.7% each); and c.-3152G>A, c.189C>T, and c.-41.-40 dup (2.3% each). Among the 20 infants with the c.211G>A variant, eight (40.0%) had a homozygous genotype and 12 (60.0%) had a heterozygous genotype. Infants harboring other variants exhibited heterozygous genotypes. When comparing the group with confirmed UGT1A1 mutations to the group without detected mutations, breastfeeding was the only significant factor (p=0.027). No significant differences were found between the group with singlenucleotide variants and the group with multiple genetic variants or between the homozygous genotype group with c.211G>A and the heterozygous genotype group. Conclusion Neonates with prolonged unconjugated hyperbilirubinemia may have a higher chance of UGT1A1 mutation than expected. Analysis of UGT1A1 mutations may be beneficial in infants with prolonged unexplained jaundice.

Abstract Background Severe neonatal hyperbilirubinemia could lead to kernicterus and neonatal death. This study aimed to analyze the association between single nucleotide polymorphisms in genes involved in bilirubin metabolism and the incidence of severe hyperbilirubinemia. Methods A total of 144 neonates with severe hyperbilirubinemia and 50 neonates without or mild hyperbilirubinemia were enrolled in 3 institutions between 2019 and 2020. Twelve polymorphisms of 5 genes (UGT1A1, SLCO1B1, SLCO1B3, BLVRA, and HMOX1) were analyzed by PCR amplification of genomic DNA. Genotyping was performed using an improved multiplex ligation detection reaction technique based on ligase detection reaction. Results The frequencies of the A allele in UGT1A1-rs4148323 and the C allele in SLCO1B3-rs2417940 in the severe hyperbilirubinemia group (30.2% and 90.6%, respectively) were significantly higher than those in the controls (30.2% vs.13.0%, 90.6% vs. 78.0%, respectively, both p

Background: Severe delayed diarrhea and hematological toxicity limit the use of irinotecan. Uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) is a critical enzyme in irinotecan metabolism. The study aims to investigate the safety and efficacy of irinotecan under the guidance of the pre-treatment UGT1A1 genotype in the second-line treatment of gastric cancer. Methods: This study involved 110 patients. Irinotecan was injected intravenously every 3 weeks, and the dose of irinotecan was determined by polymorphism of the UGT1A1 gene, which was divided into three groups (125 mg/m2: GG type; 100 mg/m2: GA type; 75 mg/m2: AA type). The primary end point was overall survival (OS), the secondary end points were progression-free survival (PFS) and safety. Results: One hundred and seven patients received irinotecan treatment and three patients with AA type received paclitaxel treatment. Among 107 patients, there were no significant differences in PFS (4.8 m vs 4.9 m vs 4.4 m; p = 0.5249) and OS (9.3 m vs 9.3 m vs NA; p = 0.6821) among patients with GG/GA/AA subtypes after dose adjustment. For the patient with homozygosity mutation, treatment was switched to paclitaxel. There were no significant differences in PFS and OS among patients with different alleles or after dose adjustment (p > 0.05). There was a significant difference in the risk of delayed diarrhea (p = 0.000), leukopenia (p = 0.003) and neutropenia (p = 0.000) in patients with different UGT1A1*6 genotypes, while no difference in patients with different UGT1A1* 28 genotypes. Additionally, grade 3/4 diarrhea, neutropenia, and leukopenia were significantly more common in AA genotype patients compared to GG (2%, 19%, 24%) or GA (23%, 31%, 31%) genotype patients. Conclusion: Individual irinotecan treatment shows encouraging survival and tolerability outcomes in patients with GG/GA subtype. Irinotecan may be not suitable for patients with AA subtype. [ABSTRACT FROM AUTHOR]

Purpose: Uridine diphosphate glucuronosyltransferase 1A isoform 1 (UGT1A1) is a crucial enzyme in bilirubin metabolism. Mutations in this gene cause prolonged unconjugated hyperbilirubinemia in infants. This study aimed to investigate the prevalence of UGT1A1 mutations and their association with prolonged, unexplained, and unconjugated hyperbilirubinemia in infants. Methods: From July 2019 to March 2023, 74 infants with prolonged jaundice lasting >21 days were enrolled in this study. Diagnostic evaluations, including UGT1A1 mutation analysis, were performed to identify the underlying causes of hyperbilirubinemia. This retrospective review evaluated the incidence and types of mutations in UGT1A1. The clinical and laboratory findings were compared based on the specific mutations detected. Results: Thirty-three infants agreed to UGT1A1 mutation analysis, and 30 (90.9%) were positive for UGT1A1 mutations. Single-nucleotide variants were detected in 20 (66. %) infants. The remaining 10 (33.3%) infants had multiple variants. No significant demographic differences were observed between the group that underwent UGT1A1 mutation analysis and the group that did not. Among the identified genetic variants, c.211G>A (46.5%) and c.-3275T>G (30.2%) were the two most common variants. The other variants had the following percentages: c.1456T>G, c.-64G>C, and c.1091C>T (4.7% each); and c.-3152G>A, c.189C>T, and c.-41.-40 dup (2.3% each). Among the 20 infants with the c.211G>A variant, eight (40.0%) had a homozygous genotype and 12 (60.0%) had a heterozygous genotype. Infants harboring other variants exhibited heterozygous genotypes. When comparing the group with confirmed UGT1A1 mutations to the group without detected mutations, breastfeeding was the only significant factor (P=0.027). No significant differences were found between the group with singlenucleotide variants and the group with multiple genetic variants or between the homozygous genotype group with c.211G>A and the heterozygous genotype group. Conclusion: Neonates with prolonged unconjugated hyperbilirubinemia may have a higher chance of UGT1A1 mutation than expected. Analysis of UGT1A1 mutations may be beneficial in infants with prolonged unexplained jaundice. [ABSTRACT FROM AUTHOR]

Background: Severe neonatal hyperbilirubinemia could lead to kernicterus and neonatal death. This study aimed to analyze the association between single nucleotide polymorphisms in genes involved in bilirubin metabolism and the incidence of severe hyperbilirubinemia. Methods: A total of 144 neonates with severe hyperbilirubinemia and 50 neonates without or mild hyperbilirubinemia were enrolled in 3 institutions between 2019 and 2020. Twelve polymorphisms of 5 genes (UGT1A1, SLCO1B1, SLCO1B3, BLVRA, and HMOX1) were analyzed by PCR amplification of genomic DNA. Genotyping was performed using an improved multiplex ligation detection reaction technique based on ligase detection reaction. Results: The frequencies of the A allele in UGT1A1-rs4148323 and the C allele in SLCO1B3-rs2417940 in the severe hyperbilirubinemia group (30.2% and 90.6%, respectively) were significantly higher than those in the controls (30.2% vs.13.0%, 90.6% vs. 78.0%, respectively, both p < 0.05). Haplotype analysis showed the ACG haplotype of UGT1A1 were associated with an increased hyperbilirubinemia risk (OR 3.122, p = 0.001), whereas the GCG haplotype was related to a reduced risk (OR 0.523, p = 0.018). Conclusion: The frequencies of the A allele in rs4148323 and the C allele in rs2417940 are highly associated with the incidence of severe hyperbilirubinemia in Chinese Han neonates. Trial registration: Trial registration number:ChiCTR1800020424; Date of registration:2018-12-29. [ABSTRACT FROM AUTHOR]

Background: Despite robust evidence and international guidelines, to support routine pharmacogenetic (PGx) testing, integration in practice has been limited. This study explored clinicians' views and experiences of pre-treatment DPYD and UGT1A1 gene testing and barriers to and enablers of routine clinical implementation. Methods: A study-specific 17-question survey was emailed (01 February–12 April 2022) to clinicians from the Medical Oncology Group of Australia (MOGA), the Clinical Oncology Society of Australia (COSA) and International Society of Oncology Pharmacy Practitioners (ISOPP). Data were analysed and reported using descriptive statistics. Results: Responses were collected from 156 clinicians (78% medical oncologists, 22% pharmacists). Median response rate of 8% (ranged from 6% to 24%) across all organisations. Only 21% routinely test for DPYD and 1% for UGT1A1. For patients undergoing curative/palliative intent treatments, clinicians reported intent to implement genotype-guided dosing by reducing FP dose for DPYD intermediate metabolisers (79%/94%), avoiding FP for DPYD poor metabolisers (68%/90%), and reducing irinotecan dose for UGT1A1 poor metabolisers (84%, palliative setting only). Barriers to implementation included: lack of financial reimbursements (82%) and perceived lengthy test turnaround time (76%). Most Clinicians identified a dedicated program coordinator, i.e., PGx pharmacist (74%) and availability of resources for education/training (74%) as enablers to implementation. Conclusion: PGx testing is not routinely practised despite robust evidence for its impact on clinical decision making in curative and palliative settings. Research data, education and implementation studies may overcome clinicians' hesitancy to follow guidelines, especially for curative intent treatments, and may overcome other identified barriers to routine clinical implementation. [ABSTRACT FROM AUTHOR]

This study investigated the prevalence of UGT1A1 genotypes in patients at a specialized tertiary tumor hospital and examined the association between UGT1A1 gene polymorphisms and adverse reactions following irinotecan administration in real-world patients. We conducted a retrospective analysis of data from 42 patients who underwent UGT1A1 genetic testing between May 2017 and December 2021 at the hospital. We specifically focused on 31 of these patients, summarizing the occurrence of both hematological and non-hematological adverse reactions after irinotecan treatment. The findings revealed a heterozygous mutation rate of 21.9% for the UGT1A128 gene, a homozygous mutation rate of 4.9%, and a heterozygous mutation rate of 31.5% for the UGT1A16 gene. Notably, no homozygous mutations were detected. Analysis of patients with UGT1A1*6 and *28 heterozygous mutations showed no significant differences in hematological and non-hematological adverse reactions compared to wild-type patients. Hematological adverse reactions encompassed neutropenia, leukopenia, thrombocytopenia, and anemia, while non-hematological reactions included increased ALT/AST, ALP/GGT, bilirubin, as well as fatigue, nausea, vomiting, and delayed diarrhea. Remarkably, the incidence of delayed diarrhea in patients with UGT1A1 *6 and *28 mutations was 100%, suggesting a higher risk in those with double mutations, warranting increased attention. In conclusion, while no significant differences in adverse reactions were observed between UGT1A1 heterozygous mutation patients and wild-type patients following irinotecan application, it is important to note that further confirmation of these findings is necessary through an expanded sample size. [ABSTRACT FROM AUTHOR]

BackgroundCrigler-Najjar syndrome (CNS) is caused by mutations in uridine 5′-diphosphate glucuronyltransferase (UGT1A1) resulting in enzyme deficiency and hyperbilirubinemia. Type II CNS patients could respond to phenobarbital treatment and survive. This study presents a rare case of type II CNS.Case summaryThe proband was a 29-year-old male patient admitted with severe jaundice. A hepatic biopsy showed bullous steatosis of the peri-central veins of the hepatic lobule, sediment of bile pigment, and mild periportal inflammation with normal liver plate structure. The type II CNS was diagnosed by routine genomic sequencing which found that the proband with the Gry71Arg/Tyr486Asp compound heterozygous mutations in the UGT1A1 gene. After treatment with phenobarbital (180 mg/day), his bilirubin levels fluctuated between 100 and 200 μmol/L for 6 months and without severe icterus.ConclusionType II CNS could be diagnosed by routine gene sequencing and treated by phenobarbital.

The main treatment regimen for patients with metastatic colorectal cancer is still cycle-based chemotherapy with fluoropyridines combined with oxaliplatin and/or irinotecan. The activity of these chemotherapeutic agents depends on a predominant specific metabolism pathway. Therefore, the genetic features of the patient become important as a prognostic factor for the occurrence and severity of adverse events during therapy. The review addresses current views about the mechanisms of toxic activity of irinotecan and fluoropyrimidines, analyzes the results of pharmacogenotyping of UGT1A1 and DPYD polymorphisms, and published studies assessing the relationship between genetic variants of these genes and the safety of chemotherapy. A significant role of the population component is noted both in the distribution of gene allele frequencies and in their phenotypic expression. For some polymorphisms of the DPYD gene, dose-dependent associations with the toxicity of 5-fluorouracil have been established. Nevertheless, they determine only 1–8% of cases out of 40–60% of patients with adverse events and DPD protein deficiency associated with other enzyme activity reduction mechanisms. The pharmacological significance of UGT1A1 genetic variations is associated with toxicity prediction and helps allocate patients for more effective high-dose irinotecan therapy. Data is presented on the pharmacogenotyping of these markers to establish the dose of drugs in various national guidelines. Currently, the heterogeneity of the available pharmacogenetic data leaves open the question of determining the most appropriate dosing strategies for irinotecan and fluoropyrimidines. The widespread introduction of UGT1A1 and DPYD genotyping into clinical practice balances the economic feasibility and predictive value of biomarkers. As pharmacogenomics evolves rapidly, more robust research would overcome existing hurdles and facilitate personalized drug dosage decisions.

Abstract Background Jaundice in the newborn period is a very common entity; rare inherited causes are often forgotten. Persistent unconjugated hyperbilirubinemia in the intermediate levels with non-hemolytic features must prompt the necessity for evaluating for genetic defects in bilirubin metabolism. Case presentation Three-and-a-half-month-old first-born girl of consanguineous marriage presented with jaundice from day 5 of life. Dark yellow color urine or pale stools were not present. Antenatal and birth history was normal. She had mild pallor and icterus and no hepatosplenomegaly. Total serum bilirubin was 8.2 mg/dl, and direct was 0.4 mg/dl. Workup for hemolytic anemia, thyroid function test, and sonography of abdomen was normal. Syrup phenobarbitone was started, and bilirubin levels after dropped to 2 mg/dl. Crigler-Najjar type II syndrome (CN II) or Gilbert’s syndrome (GS) was suspected. Next-generation sequencing for UGT1A1 gene mutation showed homozygous missense mutation consistent with CN II and 7 TA repeats in the promoter region consistent with GS. Bilirubin levels gradually fell after starting oral phenobarbitone syrup, and at 5 years of age, a trial of withholding phenobarbitone was given, and bilirubin levels remained lower, and she is asked to follow-up with bilirubin levels every 15 days to assess the need for reintroducing the therapy. Parents are planning for a second pregnancy, and a preconception genetic counseling has been done. Conclusion Genetic confirmation of coexistence of mutations causing GS and CN II have an implication on long-term neurological complications of unconjugated hyperbilirubinemia in stress or crisis situations. Prenatal diagnostic testing must be advised for detecting homozygous UGT1A1 mutations to diagnose CN II and Gilbert mutations for each of the future pregnancies. Considering the side effects of long-term phenobarbitone therapy, the decision can be taken on case-to-case basis of stopping the therapy while monitoring TSB levels.

Polymorphisms of the uridine-diphospho-glucuronosyltransferase 1A1 (UGT1A1) gene, hepatic solute carrier organic anion transporter 1B1/B3 (SLCO1B1/3) gene, and glutathione S-transferase (GST) gene have been associated with significant hyperbilirubinemia in some populations. This study aims to determine whether the variation of UGT1A1, SLCO1B1/3 and GST genes play an important role in neonatal hyperbilirubinemia in Turkish newborn infants. The study included 61 idiopathic hyperbilirubinemia cases, 28 prolonged jaundice cases, and 41 controls. Ten common polymorphisms in four genes involved in bilirubin metabolism were examined. Polymerase chain reaction-restriction fragment length polymorphism method was used to detect variants of those genes. No association was found between the variants of UGT1A1 at nt 211, the SLCO1B1 gene at nt 388, 463, 521, 1463, the SLCO1B3 gene at nt 334, 727+118, 1865+19721, and the GST gene at nt 313, 341, and neonatal hyperbilirubinemia. There was no difference between the case and control groups in terms of allele frequencies of these genes (except SLCO1B3 at nt 334) (p>0.05 in all comparisons). The presence of the G allele of the SLCO1B3 at nt 334 variant gene seemed to protect from jaundice in infants with idiopathic hyperbilirubinemia. These gene polymorphisms currently studied do not seem to modulate the risk of hyperbilirubinemia in Turkish newborn infants. [ABSTRACT FROM AUTHOR]

Background: Jaundice in the newborn period is a very common entity; rare inherited causes are often forgotten. Persistent unconjugated hyperbilirubinemia in the intermediate levels with non-hemolytic features must prompt the necessity for evaluating for genetic defects in bilirubin metabolism. Case presentation: Three-and-a-half-month-old first-born girl of consanguineous marriage presented with jaundice from day 5 of life. Dark yellow color urine or pale stools were not present. Antenatal and birth history was normal. She had mild pallor and icterus and no hepatosplenomegaly. Total serum bilirubin was 8.2 mg/dl, and direct was 0.4 mg/dl. Workup for hemolytic anemia, thyroid function test, and sonography of abdomen was normal. Syrup phenobarbitone was started, and bilirubin levels after dropped to 2 mg/dl. Crigler-Najjar type II syndrome (CN II) or Gilbert's syndrome (GS) was suspected. Next-generation sequencing for UGT1A1 gene mutation showed homozygous missense mutation consistent with CN II and 7 TA repeats in the promoter region consistent with GS. Bilirubin levels gradually fell after starting oral phenobarbitone syrup, and at 5 years of age, a trial of withholding phenobarbitone was given, and bilirubin levels remained lower, and she is asked to follow-up with bilirubin levels every 15 days to assess the need for reintroducing the therapy. Parents are planning for a second pregnancy, and a preconception genetic counseling has been done. Conclusion: Genetic confirmation of coexistence of mutations causing GS and CN II have an implication on long-term neurological complications of unconjugated hyperbilirubinemia in stress or crisis situations. Prenatal diagnostic testing must be advised for detecting homozygous UGT1A1 mutations to diagnose CN II and Gilbert mutations for each of the future pregnancies. Considering the side effects of long-term phenobarbitone therapy, the decision can be taken on case-to-case basis of stopping the therapy while monitoring TSB levels. [ABSTRACT FROM AUTHOR]

Furosemide is a diuretic and is used for the treatment of patients with heart failure (HF). It has been found that in some HF patients, the drug does not treat patients efficiently. This condition is named as furosemide resistance. In this study, it is aimed to investigate the relationship between UDP‐glucuronosyltransferase 1 (UGT1A1) and interleukine‐6 (IL‐6) variations with furosemide resistance in HF patients. Sixty HF patients using furosemide (patient group) and 30 healthy individuals (control group) were enrolled in this study. Patients were divided into two subgroups as non‐responders (furosemide resistant) group (n = 30) and the responders (non‐resistant) group (n = 30) according to the presence of furosemide resistance (n = 30). Variations in the first exon of UGT1A1 and rs1800795 and rs1800796 variations in IL‐6 were analyzed by direct sequencing and real‐time polymerase chain reaction (RT‐PCR), respectively. The effects of newly detected mutations on 3‐D protein structure were analyzed by in silico analysis. At the end of the study, 11 variations were detected in UGT1A1, of which nine of them are novel and eight of them cause amino acid change. Also, rs1800795 and rs1800796 variations were detected in all the groups. When patient and control groups were compared with each other, rs1800796 mutation in IL‐6 was found statistically high in the patient group (p = 0.027). When the three groups were compared with each other, similarly, rs1800796 mutation in IL‐6 was found statistically high in the non‐responders group (p = 0.043). When allele distributions were compared between the patient and control groups, the C allele of rs1800795 mutation in IL‐6 was found statistically high in the patient group (p = 0.032). When allele distributions were compared between the three groups, 55T‐insertion in UGT1A1 was found statistically high in the non‐responders group (p = 0.017). According to in silico analysis results, two variations were found deleterious and six variations were detected as probably damaging to protein functions. Our study may contribute to the elucidation of pharmacogenetic features (drug response–gene relationship) and the development of individual‐specific treatment strategies in HF patients using furosemide. [ABSTRACT FROM AUTHOR]

Uridine diphosphate glucuronosyltransferases (UGTs) are highly expressed in the liver and are involved in the metabolism of many drugs. In particular, UGT1A1 has a genetic polymorphism that causes decreased activity, leading to drug-induced hepatotoxicity. Therefore, an in vitro evaluation system that accurately predicts the kinetics of drugs involving UGT1A1 is required. However, there is no such evaluation system because of the absence of the UGT1A1-selective inhibitor. Here, using human induced pluripotent stem (iPS) cells, genome editing technology, and organoid technology, we generated UGT1A1-knockout human iPS hepatocyte-derived liver organoids (UGT1A1-KO i-HOs) as a model for UGT1A1-specific kinetics and toxicity evaluation. i-HOs showed higher gene expression of many drug-metabolizing enzymes including UGT1A1 than human iPS cell-derived hepatocyte-like cells (iPS-HLCs), suggesting that hepatic organoid technology improves liver functions. Wild-type (WT) i-HOs showed similar levels of UGT1A1 activity to primary human (cryopreserved) hepatocytes, while UGT1A1-KO i-HOs completely lost the activity. Additionally, to evaluate whether this model can be used to predict drug-induced hepatotoxicity, UGT1A1-KO i-HOs were exposed to SN-38, the active metabolite of irinotecan, an anticancer drug, and acetaminophen and confirmed that these cells could predict UGT1A1-mediated toxicity. Thus, we succeeded in generating model cells that enable evaluation of UGT1A1-specific kinetics and toxicity.

Cristina Montrasio,1 Stefania Cheli,1 Emilio Clementi2,3 1Unit of Clinical Pharmacology, ASST Fatebenefratelli Sacco, L. Sacco University Hospital, Milan, Italy; 2Clinical Pharmacology Unit, Department of Biomedical and Clinical Sciences, L. Sacco University Hospital, Università degli Studi di Milano, Milan, Italy; 3Scientific Institute IRCCS Eugenio Medea, Bosisio Parini, ItalyCorrespondence: Cristina Montrasio, Unit of Clinical Pharmacology, Department of Laboratory Medicine, ASST Fatebenefratelli-Sacco, Milan, Italy, Email cristina.montrasio@asst-fbf-sacco.itAbstract: The application of pharmacogenetics in oncology is part of the routine clinical practice. In particular, genotyping of dihydropyrimidine dehydrogenase (DPYD) and UDP-glucuronosyltransferase (UGT1A1) is crucial to manage the treatment of patients taking fluoropyrimidines and irinotecan. The unique approach of our laboratory to the pharmacogenetic diagnostic service in oncology is to combine two real-time PCR methods, LightSNiP assay (TIB MOLBIOL), and more recently FRET (Fluorescent Resonance Energy Transfer) probes technology (Nuclear Laser Medicine), plus TaqMan assay (Thermo Fisher) for the confirmation of the presence of variant alleles on DNA from a second extraction. We found that both the FRET and LightSNiP assays, where detection occurs by melting curve analysis, offer an advantage over the competing TaqMan technology. Whereas unexpected genetic variants may be missed using a mutation-specific TaqMan assay, the information thus obtained can be useful to adjust the therapy in case of unexpected post-treatment toxicity. The combination of TaqMan and FRET assays helped us to achieve more accurate genotyping and a correct result for the patient. The added value of the DPYD FRET assay is the possibility of detecting, with the same amplification profile of the polymorphisms detailed in the guidelines, also the c.2194G>A (&ast;6 rs1801160), cited in the recommendations as a variant to be investigated in case of severe toxicity. Regarding the UGT1A1 (TA)n promoter polymorphism (rs3064744), the distinctive and positive feature of the FRET assay is to allow clearly identifying all those potential variant alleles, including the (TA)5 and (TA)8 alleles, that are frequent in African Americans. Our clinical practice emphasizes the importance of not only rapid and easy-to-use assays, such as the new FRET ones, but also of accurate and comprehensive genotyping for good pharmacogenetic diagnostic activity.Keywords: real-time PCR, melting curve analysis, DPYD, UGT1A1, pharmacogenetics

К врожденным наследственным неконьюгировнным гипербилирубинемиям относятся синдромы Жильбера, Криглера-Найяра 1 типа и Криглера-Найяра 2 типа (или болезнь Arias). В их основе лежит наследственный дефицит фермента – билирубин-уридин-5'-дифосфатглюкуронозилтрансферазы (UGT1A1), участвующего в глюкуронизации билирубина. Дефицит фермента обусловлен мутациями гена UGT1A1, который обеспечивает активность UGT1A1. Полная или почти полная потеря (синдром Криглера-Найяра 1 типа) или снижение активности (синдром Жильбера и синдром Криглера-Найяра 2 типа) UGT1A1 приводят к нарушению конверсии билирубина в печени с накоплением в крови неконьюгированного билирубина. Синдромы различают по уровню билирубина в плазме крови, реакции на введение фенобарбитала, наличию или отсутствию глюкуронидов билирубина в желчи.

Crigler-Najjar syndrome is a rare disorder of bilirubin metabolism caused by uridine diphosphate glucuronosyl transferase 1A1 (UGT1A1) mutations characterized by hyperbilirubinemia and jaundice. No cure currently exists; treatment options are limited to phototherapy, whose effectiveness diminishes over time, and liver transplantation. Here, we evaluated the therapeutic potential of systemically administered, lipid nanoparticle-encapsulated human UGT1A1 (hUGT1A1) mRNA therapy in a Crigler-Najjar mouse model. Ugt1 knockout mice were rescued from lethal post-natal hyperbilirubinemia by phototherapy. These adult Ugt1 knockout mice were then administered a single lipid nanoparticle-encapsulated hUGT1A1 mRNA dose. Within 24 h, serum total bilirubin levels decreased from 15 mg/dL (256 μmol/L) to

Bilirubin-induced neurological damage (BIND), which might progress to kernicterus, occurs as a consequence of defects in the bilirubin conjugation machinery, thus enabling albumin-unbound free bilirubin (BF) to cross the blood–brain barrier and accumulate within. A defect in the UGT1A1 enzyme-encoding gene, which is directly responsible for bilirubin conjugation, can cause Crigler–Najjar syndrome (CNS) and Gilbert's syndrome. We used human-induced pluripotent stem cell (hiPSC)-derived 3D brain organoids to model BIND in vitro and unveil the molecular basis of the detrimental effects of BF in the developing human brain. Healthy and patient-derived iPSCs were differentiated into day-20 brain organoids, and then stimulated with 200 nM BF. Analyses at 24 and 72 h post-treatment point to BF-induced neuro-inflammation in both cell lines. Transcriptome, associated KEGG, and Gene Ontology analyses unveiled the activation of distinct inflammatory pathways, such as cytokine–cytokine receptor interaction, MAPK signaling, and NFκB activation. Furthermore, the mRNA expression and secretome analysis confirmed an upregulation of pro-inflammatory cytokines such as IL-6 and IL-8 upon BF stimulation. This novel study has provided insights into how a human iPSC-derived 3D brain organoid model can serve as a prospective platform for studying the etiology of BIND kernicterus. [ABSTRACT FROM AUTHOR]

Pyruvate Kinase Deficiency (PKD) and Crigler-Najjar syndrome are rare autosomal recessive liver diseases. PKD is caused by homozygous or compound heterozygous mutations in the PKLR gene, leading to non-spherocytic hereditary hemolytic anemia. On the other hand, Crigler-Najjar syndrome (CNS-II) is characterized by the loss or reduced activity of UDPglucuronosyltransferase, resulting in elevated levels of unconjugated bilirubin, which is the primary cause of disease manifestation. To date, there have been no reported cases of patients with both conditions. In this case report, we present the unique clinical course of a 15-year-old Chinese patient with both PKD and CNS-II. The patient was admitted for evaluation of hyperbilirubinemia and exhibited yellowish skin color, icteric sclera, and splenomegaly upon physical examination. Extensive laboratory examinations ruled out viral, hemolytic, autoimmune, and inborn or acquired metabolic etiologies of liver injury. Histopathological findings indicated benign recurrent intrahepatic cholestasis (BRIC) and hemosiderosis. Surprisingly, targeted next-generation sequencing (NGS) of the patient's blood did not reveal any mutation sites associated with BRIC. Instead, it identified a novel homozygous pathogenic variant of the PKLR gene [c.1276C>T (p.Arg426Trp)] and a rare heterozygous variant of UGT1A1 gene [c.-55_-54insAT, c.1091C>T (p.Pro364Leu)]. These findings strongly suggest a diagnosis of PKD and CNS-II in the patient. Treatment with 500 mg/day of ursodeoxycholic acid proved to be effective, rapidly reducing the patient's total bilirubin levels and shortening the symptomatic period. This case highlights the importance of genetic diagnosis in accurately identifying the underlying cause of hyperbilirubinemia, especially in patients with rare hereditary diseases. Furthermore, NGS can provide valuable insights into the genotype-phenotype correlation of PKD and CNS-II. [ABSTRACT FROM AUTHOR]

Crigler–Najjar Syndrome (CNS) with residual activity of UDP-glucuronosyltransferase 1A1 (UGT1A1) and no need for daily phototherapy is called mild Crigler–Najjar Syndrome. Most of these patients need medical treatment for enzyme induction (phenobarbital) to lower blood levels of unconjugated bilirubin (UCB). Apart from this, no long-term problems have been described so far. The phenotype of patients with the homozygous pathogenic variant c.115C>G p.(His39Asp) in UGT1A1 is described as variable. Clinical observations of our patients led to the assumption that patients with variant c.115C>G have a mild CNS phenotype while having a high risk of developing progressive liver disease. For mild CNS disease, progressive liver disease has not been described so far. Therefore, we conducted a retrospective multicenter analysis of 14 patients with this particular variant, aiming for better characterization of this variant. We could confirm that patients with variant c.115C>G have a high risk of progressive liver disease (seven of fourteen), which increases with age despite having a very mild CNS phenotype. Earlier predictors and causes for an unfavorable disease course are not detectable, but close follow-up could identify patients with progressive liver disease at the beginning. In conclusion, these patients need close and specialized follow-up. Our study questions whether fibrosis in the CNS is really driven by high amounts of UCB or phototherapy. [ABSTRACT FROM AUTHOR]

Bilirubin is the end product of heme catabolism, mainly produced by the breakdown of mature red blood cells. Due to its anti-inflammatory, antioxidant, antidiabetic, and antilipemic properties, circulating bilirubin concentrations are inversely associated with the risk of cardiovascular disease, type 2 diabetes, and all-cause mortality in adults. Some genetic loci associated with circulating bilirubin concentrations have been identified by genome-wide association studies in adults. We aimed to examine the relationship between circulating bilirubin, cardiometabolic risk factors, and inflammation in children and adolescents and the genetic architecture of plasma bilirubin concentrations. We measured fasting plasma bilirubin, cardiometabolic risk factors, and inflammatory markers in a sample of Danish children and adolescents with overweight or obesity (n = 1530) and in a population-based sample (n = 1820) of Danish children and adolescents. Linear and logistic regression analyses were performed to analyze the associations between bilirubin, cardiometabolic risk factors, and inflammatory markers. A genome-wide association study (GWAS) of fasting plasma concentrations of bilirubin was performed in children and adolescents with overweight or obesity and in a population-based sample. Bilirubin is associated inversely and significantly with a number of cardiometabolic risk factors, including body mass index (BMI) standard deviation scores (SDS), waist circumference, high-sensitivity C-reactive protein (hs-CRP), homeostatic model assessment for insulin resistance (HOMA-IR), hemoglobin A1c (HbA1c), low-density lipoprotein cholesterol (LDL-C), triglycerides, and the majority of measured inflammatory markers. In contrast, bilirubin was positively associated with fasting plasma concentrations of alanine transaminase (ALT), high-density lipoprotein cholesterol (HDL-C), systolic blood pressure (SDS), and the inflammatory markers GH, PTX3, THBS2, TNFRSF9, PGF, PAPPA, GT, CCL23, CX3CL1, SCF, and TRANCE. The GWAS showed that two loci were positively associated with plasma bilirubin concentrations at a p-value threshold of <5 × 10−8 (rs76999922: β = −0.65 SD; p = 4.3 × 10−8, and rs887829: β = 0.78 SD; p = 2.9 × 10−247). Approximately 25% of the variance in plasma bilirubin concentration was explained by rs887829. The rs887829 was not significantly associated with any of the mentioned cardiometabolic risk factors except for hs-CRP. Our findings suggest that plasma concentrations of bilirubin non-causally associates with cardiometabolic risk factors in children and adolescents. [ABSTRACT FROM AUTHOR]

Crigler-Najjar syndrome (CNS) is an exceedingly rare autosomal recessive disease with an estimated incidence of 1 in a million live births. CNS type 1 (CNS1) is the most severe form, characterized by severe unconjugated hyperbilirubinemia since birth due to the absence of hepatic uridine 5'-diphosphate glucuronyltransferase (UGT1A1) activity. Daily phototherapy (PT) and liver transplant (LT) are the mainstays of therapy. Here, we present a higher-than-expected incidence of CNS1 in Croatia (6,1 in a million). In the last 31 years, we treated eight CNS1 patients from five families with no reported consanguinity. Four patients are descendants of an isolated enclave in Kosovo with a small gene pool and a high potential for inbreeding. Severe unconjugated hyperbilirubinemia was verified in a neonatal period and PT was initiated. Four patients underwent LT from living-related donors. One of them had unsuccessful hepatocyte transplantation earlier. LT was successful in three patients, and one patient died due to primary graft dysfunction. Four patients are currently treated with 9–12 h daily PT with inconsistent disease control, and gradually increasing bilirubin. One patient developed kernicterus before LT, while others have normal psychomotor development and no neurologic impairment. Genetic testing of the UGT1A1 gene in six patients from three families revealed three different homozygous mutations (c.722_723 delAG, c.717_718 delAG, and c.1021 C >T), all previously described in other populations. There is a possibility of the founder effect as an explanation for the higher incidence of CNS1 in at least a subgroup of Croatians.

Bilirubin has potent biological beneficial effects, protecting against atherosclerosis, obesity, and metabolic syndrome. The aim of this study was to assess serum bilirubin concentrations and (TA)n and (GT)n microsatellite variations in the promoter regions of the UGT1A1 and HMOX1 genes, respectively, in patients with type 2 diabetes mellitus (T2DM). The study was carried out in 220 patients with T2DM and 231 healthy control subjects, in whom standard biochemical tests were performed. The (TA)n and (GT)n dinucleotide variations were determined by means of fragment (size-based) analysis using an automated capillary DNA sequencer. Compared to controls, both male and female patients with T2DM had lower serum bilirubin concentrations (9.9 vs. 12.9 μmol/L, and 9.0 vs. 10.6 μmol/L, in men and women, respectively, p < 0.001). Phenotypic Gilbert syndrome was much less prevalent in T2DM patients, as was the frequency of the (TA)7/7UGT1A1 genotype in male T2DM patients. (GT)nHMOX1 genetic variations did not differ between diabetic patients and controls. Our results demonstrate that the manifestation of T2DM is associated with lower serum bilirubin concentrations. Consumption of bilirubin due to increased oxidative stress associated with T2DM seems to be the main explanation, although (TA)n repeat variations in UGT1A1 partially contribute to this phenomenon. [ABSTRACT FROM AUTHOR]

Hepatic fibrosis is an important pathological manifestation of chronic schistosome infection. Patients with advanced schistosomiasis show varying degrees of abnormalities in liver fibrosis indicators and bilirubin metabolism. However, the relationship between hepatic fibrosis in schistosomiasis and dysregulated bilirubin metabolism remains unclear. In this study, we observed a positive correlation between total bilirubin levels and the levels of ALT, AST, LN, and CIV in patients with advanced schistosomiasis. Additionally, we established mouse models at different time points following S. japonicum infection. As the infection time increased, liver fibrosis escalated, while liver UGT1A1 consistently exhibited a low expression, indicating impaired glucuronidation of bilirubin metabolism in mice. In vitro experiments suggested that SEA may be a key inhibitor of hepatic UGT1A1 expression after schistosome infection. Furthermore, a high concentration of bilirubin activated the NF-κB signaling pathway in L-O2 cells in vitro. These findings suggested that the dysregulated glucuronidation of bilirubin caused by S. japonicum infection may play a significant role in schistosomiasis liver fibrosis through the NF-κB signaling pathway.

Purpose: The variability on irinotecan (IRI) pharmacokinetics and toxicity has been attributed mostly to genetic variations in the UGT1A1 gene, responsible for conjugation of the active metabolite SN-38. Also, CYP3A mediates the formation of inactive oxidative metabolites of IRI. The association between the occurrence of severe adverse events, pharmacokinetics parameters, and UGT1A1 and CYP3A4 predicted phenotypes was evaluated, as the evaluation of [SN-38]/IRI dose ratio as predictor of severe adverse events. Methods: Forty-one patients undergoing IRI therapy were enrolled in the study. Blood samples were collected 15 min after the end of drug the infusion, for IRI, SN-38, SN-38G, bilirubin concentrations measurements, and UGT1A1 and CYP3A genotype estimation. Data on adverse event was reported. Results: Fifteen patients (36.5%) developed grade 3/4 adverse events. A total of 9.8% (n = 4) of the patients had UGT1A1 reduced activity phenotype, and 48.7% (n = 20) had UGT1A1 and 63.4% (n = 26) CYP3A intermediary phenotypes. Severe neutropenia and diarrhea were more prevalent in patients with reduced UGT1A1 in comparison with functional metabolism (50% and 75% versus 0% and 13%, respectively). SN-38 levels and its concentrations adjusted by IRI dose were significantly correlated to toxicity (rs = 0.31 (p = 0.05) and rs = 0.425 (p < 0.01)). The [SN-38]/IRI dose ratio had a ROC curve of 0.823 (95% CI 0.69–0.956) to detect any severe adverse event and 0.833 (95% CI 0.694–0.973) to detect severe diarrhea. The cut-off of 0.075 ng mL−1 mg−1 had 100% sensitivity and 65.7% specificity to predict severe diarrhea. Conclusion: Our data confirmed the relevance of the pre-emptive genotypic information of UGT1A1. The [SN-38]/IRI ratio, measured 15 min after the end of the IRI infusion, was a strong predictor of severe toxicity and could be applied to minimize the burden of patients after IRI administration. [ABSTRACT FROM AUTHOR]

Breast milk is tailored for optimal growth in all infants; however, in some infants, it is related to a unique phenomenon referred to as breast milk jaundice (BMJ). BMJ is a type of prolonged unconjugated hyperbilirubinemia that is often late onset in otherwise healthy-appearing newborns, and its occurrence might be related to breast milk itself. This review aims to systematically evaluate evidence regarding breast milk composition and the development of BMJ in healthy neonates. PubMed, Scopus and Embase were searched up to 13 February 2023 with key search terms, including neonates, hyperbilirubinemia, and breastfeeding. A total of 678 unique studies were identified and 12 were ultimately included in the systematic review with narrative synthesis. These included studies covered both nutritional compositions (e.g., fats and proteins) and bioactive factors (e.g., enzymes and growth factors) of breast milk and formally assessed the difference in the concentration (or presence) of various endogenous components of breast milk collected from mothers of BMJ infants and healthy infants. The results were inconsistent and inconclusive for most of the substances of interest, and there was only a single study available (e.g., total energy and mineral content, bile salts and cytokines); conflicting or even contradictory results arose when there were two or more studies on the subject matter (e.g., fats and free fatty acids contents and epidermal growth factor). The etiology of BMJ is likely multifactorial, and no single constituent of breast milk could explain all the BMJ cases observed. Further well-designed studies are warranted to investigate the complex interaction between maternal physiology, the breast milk system and infant physiology before this field could be progressed to uncover the etiology of BMJ. [ABSTRACT FROM AUTHOR]

Genetic variation in UDP-glucuronosyltransferase 1A1 gene (UGT1A1) is a lithogenic risk factor for gallstone formation. This study aimed to assess genotype and allele frequencies of common UGT1A1 variants in patients with gallstone and hepatitis B virus (HBV)-related hepatic failure. This study enrolled 113 healthy individuals (CTRL), 54 patients with HBV infection (HBV), 134 patients with gallstone-free hepatic failure and HBV infection, and 34 patients with gallstone-related hepatic failure and HBV infection (GRHF). Peripheral venous blood samples were collected for genomic DNA isolation. Polymerase chain reaction amplification was carried out for UGT1A1, followed by direct sequencing. Analysis for genotype and allele frequencies of UGT1A1 variants (UGT1A1*6, UGT1A1*27, UGT1A1*28, and UGT1A1*60) was performed. The allele distributions of the four groups did not deviate from Hardy–Weinberg equilibrium. Allele (A) and genotype (CA) frequency distributions of UGT1A1*27 were significantly different between GRHF and CTRL, or between GRHF and HBV. GRHF and CTRL exhibited significant differences in allele (A) and genotype (CA) frequency distributions of UGT1A1*28. Linkage disequilibrium analysis suggested that haplotype G-G-[TA]7-T may be associated with gallstone in HBV-related hepatic failure. Our data reveal that UGT1A1*27 and UGT1A1*28 variants are significantly observed in patients with GRHF compared to healthy individuals.

The effects of UGT1A1 gene polymorphisms or prior irinotecan treatment on treatment outcomes of nanoliposomal-irinotecan plus 5-fluorouracil/leucovorin (nal-IRI+5-FU/LV) in patients with unresectable pancreatic ductal adenocarcinoma (PDAC) are not established. This multicenter, retrospective cohort study compared treatment outcomes in patients with UGT1A1*1/*1 and those with UGT1A1*1/*6 or *1/*28 genotypes. We also analyzed the impact of prior irinotecan treatment on survival outcomes in 54 patients treated with nal-IRI+5-FU/LV. Comparable effectiveness was found regardless of the UGT1A1 genotypes. While no significant differences were found, grade ≥3 neutropenia and febrile neutropenia were more frequent in patients with UGT1A1*1/*6 or *1/*28 than in those with UGT1A1*1/*1 genotypes (grade ≥3 neutropenia, 50.0% vs. 30.8%, p = 0.24; febrile neutropenia, 9.1% vs. 0.0%, p = 0.20, respectively). No significant difference in progression-free survival (PFS) and overall survival (OS) was observed between irinotecan-naïve-patients and other patients. However, irinotecan-resistant patients showed significantly shorter PFS (hazard ratio (HR) 2.83, p = 0.017) and OS (HR 2.58, p = 0.033) than other patients. Our study indicated that patients with UGT1A1*1/*6 or *1/*28 may be prone to neutropenia, though further study is needed. The survival benefit of nal-IRI+5-FU/LV could be maintained in patients without disease progression after irinotecan therapy. [ABSTRACT FROM AUTHOR]

Several population studies have observed lower serum bilirubin levels in patients with non-alcoholic fatty liver disease (NAFLD). Yet, treatments to target this metabolic phenotype have not been explored. Therefore, we designed an N-Acetylgalactosamine (GalNAc) labeled RNAi to target the enzyme that clears bilirubin from the blood, the UGT1A1 glucuronyl enzyme (GNUR). In this study, male C57BL/6J mice were fed a high-fat diet (HFD, 60%) for 30 weeks to induce NAFLD and were treated subcutaneously with GNUR or sham (CTRL) once weekly for six weeks while continuing the HFD. The results show that GNUR treatments significantly raised plasma bilirubin levels and reduced plasma levels of the bilirubin catabolized product, urobilin. We show that GNUR decreased liver fat content and ceramide production via lipidomics and lowered fasting blood glucose and insulin levels. We performed extensive kinase activity analyses using our PamGene PamStation kinome technology and found a reorganization of the kinase pathways and a significant decrease in inflammatory mediators with GNUR versus CTRL treatments. These results demonstrate that GNUR increases plasma bilirubin and reduces plasma urobilin, reducing NAFLD and inflammation and improving overall liver health. These data indicate that UGT1A1 antagonism might serve as a treatment for NAFLD and may improve obesity-associated comorbidities. [ABSTRACT FROM AUTHOR]

Prenatal exposure to polycyclic aromatic hydrocarbons (PAHs) is a risk factor for the occurrence of congenital heart diseases (CHDs). Genetic susceptibility to PAHs metabolism may modify the exposure–risk relationship. The role of uridine diphosphoglucuronosyl transferase 1A1 (UGT1A1) genetic polymorphisms for modulating the impacts of prenatal PAHs exposure on the risk of CHDs remains to be discovered. The aim of this study was to investigate whether maternal UGT1A1 genetic polymorphisms are associated with fetal susceptibility to CHDs and to assess whether the risk is modified by maternal PAHs exposure. Maternal urinary biomarker of PAHs exposure was determined in 357 pregnant women with CHDs fetuses and 270 controls (pregnant women carrying fetuses without major congenital malformations). Urinary 1-hydroxypyrene-glucuronide (1-OHPG) concentration, a sensitive biomarker for PAHs exposure, was measured using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry. Maternal single nucleotide polymorphisms (SNPs) in UGT1A1, including rs3755319, rs887829, rs4148323, rs6742078, and rs6717546, were genotyped using an improved multiplex ligation detection reaction (iMLDR) technique. Unconditional logistic regression was performed to determine the impacts of UGT1A1 polymorphisms on the risks of CHDs and their subtypes. Generalized multifactor dimensionality reduction (GMDR) was used to analyze the gene–gene and gene–PAHs exposure interactions. None of the selected UGT1A1 polymorphisms was independently associated with the risk of CHDs. The interaction between SNP rs4148323 and PAHs exposure was observed to be associated with CHDs (p<.05). Pregnant women with high-level PAHs exposure and rs4148323 had an increased risk of carrying CHDs fetuses (GA-AA vs. GG: aOR = 2.00, 95% CI = 1.06–3.79). Moreover, the joint effect of rs4148323 and PAHs exposure was found to be significantly associated with risks of septal defects, conotruncal heart defects, and right-sided obstructive malformations. Maternal genetic variations of UGT1A1 rs4148323 may modify the association between prenatal PAHs exposure and CHDs risk. This finding needs to be further confirmed in a larger-scale study. [ABSTRACT FROM AUTHOR]

Bilirubin levels in obese humans and rodents have been shown to be lower than in their lean counterparts. Some studies have proposed that the glucuronyl UGT1A1 enzyme that clears bilirubin from the blood increases in the liver with obesity. UGT1A1 clearance of bilirubin allows more conjugated bilirubin to enter the intestine, where it is catabolized into urobilin, which can be then absorbed via the hepatic portal vein. We hypothesized that when bilirubin levels are decreased, the urobilin increases in the plasma of obese humans, as compared to lean humans. To test this, we measured plasma levels of bilirubin and urobilin, body mass index (BMI), adiposity, blood glucose and insulin, and HOMA IR in a small cohort of obese and lean men and women. We found that bilirubin levels negatively correlated with BMI and adiposity in obese men and women, as compared to their lean counterparts. Contrarily, urobilin levels were positively associated with adiposity and BMI. Only obese women were found to be insulin resistant based on significantly higher HOMA IR, as compared to lean women. The urobilin levels were positively associated with HOMA IR in both groups, but women had a stronger linear correlation. These studies indicate that plasma urobilin levels are associated with obesity and its comorbidities, such as insulin resistance. [ABSTRACT FROM AUTHOR]

Abstract Hyperbilirubinemia is the main mechanism that causes neonatal jaundice, and genetics is one of the risk factors of hyperbilirubinemia. Therefore, this study aims to explore the correlation between two genes, UGT1A1 and SLCO1B1, and hyperbilirubinemia in Thai neonates. One hundred thirty seven neonates were recruited from Division of Clinical Chemistry, Ramathibodi Hospital. UGT1A1*28 and *6 were determined by pyrosequencing whereas, SLCO1B1 388A > G and 521 T > C genetic variants were determined by TaqMan® real-time polymerase chain reaction. Neonates carrying with homozygous (AA) and heterozygous (GA) variants in UGT1A1*6 were significantly related to hyperbilirubinemia development compared with wild type (GG; P C variant provide protection for Thai neonatal hyperbilirubinemia (P = 0.041). There are no significant differences in UGT1A1*28 and SLCO1B1 388A > G for the different severity of hyperbilirubinemia. The combined UGT1A1*28 and *6 polymorphism is a strong risk factor for the development of severe hyperbilirubinemia in Thai neonates. Therefore, we suggest neonates with this gene should be closely observed to avoid higher severities of bilirubin.

Abstract Background Several mutations of bilirubin uridine diphosphate-glucuronosyltransferase gene (UGT1A1) have been reported in patients with unconjugated hyperbilirubinemia. Few reports are available about the p.Pro364Leu mutation (P364L, c.1091C > T) in homozygous newborns. We describe the clinical, laboratory and therapeutic approach in two Chinese neonates with severe jaundice, homozygous for the P364L mutation. Case presentation Two Chinese breastfed female infants presented prolonged unconjugated hyperbilirubinemia at the age of 1 month. Total bilirubin was higher than 15 mg/dl (D T, p.Pro364Leu. In front of the persistently high level of unconjugated bilirubin, phototherapy was performed without persistent results. A treatment with phenobarbital was then begun and bilirubin level progressively decreased, with a complete and persistent normalization. The therapy was stopped. Conclusion UGT1A1 enzyme activity associated with the P364L mutation has been described as 35.6% of the wild-type enzyme activity. Photo-therapy and phenobarbital can be useful in front of persistently high level of unconjugated bilirubin. Our cases presented high bilirubin values, overlapping between Gilbert syndrome (GS) and Crigler-Najjar syndrome type II (CNS), but the complete normalization of bilirubin makes GS more likely. Homozygous P364L variant can be associated with severe neonatal unconjugated hyperbilirubinemia in Chinese infants, but jaundice can completely resolve in a few months, contrary to what happens in Crigler-Najjar syndrome type II.

Ching-Chun Li,1 Tsung-Kun Chang,1,2 Yen-Cheng Chen,1,3 Hsiang-Lin Tsai,1,2 Ching-Wen Huang,1,2 Wei-Chih Su,1,3 Cheng-Jen Ma,1,3 Tzu-Chieh Yin,1,4,5 Po-Jung Chen,1 Jaw-Yuan Wang1– 3,6– 8 1Division of Colorectal Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; 2Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; 3Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; 4Division of General and Digestive Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; 5Department of Surgery, Kaohsiung Municipal Tatung Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; 6Center for Cancer Research, Kaohsiung Medical University, Kaohsiung, Taiwan; 7Center for Liquid Biopsy and Cohort Research, Kaohsiung Medical University, Kaohsiung, Taiwan; 8Department of Surgery, Pingtung Hospital, Ministry of Health and Welfare, Pingtung, TaiwanCorrespondence: Jaw-Yuan Wang, Division of Colorectal Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, No. 100 Tzyou 1st Road, Kaohsiung, 807, Taiwan, Tel +886-7-3122805, Email cy614112@ms14.hinet.net; jawyuanwang@gmail.comBackground: The prognosis of metastatic colorectal cancer (mCRC) depends on the metastatic site and systemic therapy regimen. Peritoneal metastases are associated with a relatively unfavorable prognosis among patients with mCRC. In this article, we present the treatment outcomes of patients with peritoneal carcinomatosis (PC)-only, liver metastasis (LiM)-only, and lung metastasis (LuM)-only CRC.Methods: Overall, 206 mCRC patients with single-site metastasis and who had received treatment from January 2014 to December 2018 were recruited. Among 206 patients with mCRC, 15 had PC-only mCRC, 145 had LiM-only mCRC, and 46 had LuM-only mCRC. They attended regular follow-ups until November 2020, and the median follow-up period was 24.7 months (5.1– 41.3 months). Patients’ characteristics, including clinical data, gene mutation profiles, and clinical outcomes, were evaluated. All patients with PC-only CRC were treated with first-line bevacizumab and FOLFIRI, and the irinotecan dose escalation depended on UGT1A1 polymorphism.Results: Of the 206 patients, no statistical difference was observed between the PC-only, LiM-only, and LuM-only groups in terms of age, primary tumor location, RAS mutation status, BRAF mutation status, and epidermal growth factor receptor overexpression (all P > 0.05). Patients with PC-only CRC had a median progression-free survival (mPFS) of 18.0 months and a median overall survival (mOS) of 24.6 months. Patients with LiM-only or LuM-only CRC had mPFS of 18.2 and 26.6 months and mOS of 25.0 and 44.5 months, respectively. No significant differences regarding PFS and OS (both P > 0.05) between the three groups of patients with mCRC were observed.Conclusion: Our study revealed that in patients with PC-only mCRC treatment of first-line bevacizumab and FOLFIRI through irinotecan dose escalation according to UGT1A1 polymorphism could confer such patients with comparable outcomes to that of patients with LiM-only and LuM-only mCRC.Keywords: prognosis, metastatic colorectal cancer, peritoneal carcinomatosis-only, UGT1A1, irinotecan dose escalation

Background: The literature recommends that reduced dosage of CPT-11 should be applied in patients with UGT1A1 homozygous mutations, but the impact of UGT1A1 heterozygous mutations on the adverse reactions of CPT-11 is still not fully clear. Methods: A total of 107 patients with UGT1A1 heterozygous mutation or wild-type, who were treated with CPT-11 from January 2018 to September 2021 in Peking University Third Hospital, were retrospectively enrolled. The adverse reaction spectra of patients with UGT1A1*6 and UGT1A1*28 mutations were analyzed. Adverse reactions were evaluated according to National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) 5.0. The efficacy was evaluated according to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1. The genotypes of UGT1A1*6 and UGT1A1*28 were detected by digital fluorescence molecular hybridization. Results: There were 43 patients with UGT1A1*6 heterozygous mutation, 26 patients with UGT1A1*28 heterozygous mutation, 8 patients with UGT1A1*6 and UGT1A1*28 double heterozygous mutations, 61 patients with heterozygous mutation at any gene locus of UGT1A1*6 and UGT1A1*28. Logistic regression analysis showed that the presence or absence of vomiting (P=0.013) and mucositis (P=0.005) was significantly correlated with heterozygous mutation of UGT1A1*28, and the severity of vomiting (P

Benzo(a)pyrene (B[a]P) is the most widely concerned polycyclic aromatic hydrocarbons (PAHs), which metabolizes benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE) in vivo to produce carcinogenic effect on the body. Currently, there is limited research on the role of the variation of metabolic enzymes in this process. We carried out a study including 752 participants, measured the concentrations of 16 kinds PAHs in both particle and gaseous phases, urinary PAHs metabolites, leukocyte BPDE-DNA adduct and serum BPDE- Albumin (BPDE-Alb) adduct, and calculated daily intake dose (DID) to assess the cumulative exposure of PAHs. We conducted single nucleotide polymorphism sites (SNPs) of metabolic enzymes, explored the exposure–response relationship between the levels of exposure and BPDE adducts using multiple linear regression models. Our results indicated that an interquartile range (IQR) increase in B[a]P, PAHs, BaPeq, 1-hydroxypyrene (1-OHP), 1-hydroxynaphthalene (1-OHNap) and 2-hydroxynaphthalene (2-OHNap) were associated with 26.53 %, 24.24 %, 28.15 %, 39.15 %, 12.85 % and 14.09 % increase in leukocyte BPDE-DNA adduct (all P < 0.05). However, there was no significant correlation between exposure with serum BPDE-Alb adduct (P > 0.05). Besides, we also found the polymorphism of CYP1A1(Gly45Asp), CYP2C9 (Ile359Leu), and UGT1A1(downstream) may affect BPDE adducts level. Our results indicated that leukocyte BPDE-DNA adduct could better reflect the exposure to PAHs. Furthermore, the polymorphism of CYP1A1, CYP2C9 and UGT1A1affected the content of BPDE adducts. [ABSTRACT FROM AUTHOR]

• Introduction of a novel PCR melting curve analysis method for rapid detection of DPYD and UGT1A1 polymorphisms related to fluorouracil and irinotecan therapy. • High accuracy and reliability demonstrated through protocol optimization and validation on 28 patients, outperforming Multiplex qPCR, especially for heterozygous (TA) n mutations detection. • Intra- and inter-run precision analysis showed low coefficients of variation for melting temperatures (Tms) and high sensitivity with a limit of detection of 0.09 ng/μl of input genomic DNA. • The developed PCR melting curve analysis offers a rapid, simple, and cost-effective solution suitable for clinical laboratories equipped with a fluorescent PCR platform. Determination of DPYD and UGT1A1 polymorphisms prior to 5-fluorouracil and irinotecan therapy is crucial for avoiding severe adverse drug effects. Hence, there is a pressing need for accurate and reliable genotyping methods for the most common DPYD and UGT1A1 polymorphisms. In this study, we introduce a novel polymerase chain reaction (PCR) melting curve analysis method for discriminating DPYD c.1236G > A, c.1679 T > G, c.2846A > T, IVS14 + 1G > A and UGT1A1 *1, *28, *6 (G71R) genotypes. Following protocol optimization, this technique was employed to genotype 28 patients, recruited between March 2023 and October 2023, at the First Affiliated Hospital of Xiamen University. These patients included 20 with UGT1A1 *1/*1, 8 with UGT1A1 *1/*28, 4 with UGT1A1 *28/*28, 22 with UGT1A1 *6 G/G, 6 with UGT1A1 *6 G/A, 4 with UGT1A1 *6 A/A, 27 with DPYD (c.1236) G/G, 3 with DPYD (c.1236) G/A, 2 with DPYD (c.1236) A/A, 27 with DPYD (c.1679) T/T, 2 with DPYD (c.1679) T/G, 3 with DPYD (c.1679) G/G, 28 with DPYD (c.2846A/T) A/A, 2 with DPYD (c.2846A/T) A/T, 2 with DPYD (c.2846A/T) T/T, 28 with DPYD (c.IVS14 + 1) G/G, 2 with DPYD (c.IVS14 + 1) G/G, and 2 with DPYD (c.IVS14 + 1) G/G, as well as 3 plasmid standards. Method accuracy was assessed by comparing results with those from Sanger sequencing or Multiplex quantitative PCR(qPCR). Intra- and inter-run precision of melting temperatures (Tms) were calculated to evaluate reliability, and sensitivity was assessed through limit of detection examination. The new method accurately identified all genotypes and exhibited higher accuracy than Multiplex qPCR. Intra- and inter-run coefficients of variation for Tms were both ≤1.97 %, with standard deviations ≤0.95 °C. The limit of detection was 0.09 ng/μL of input genomic DNA. Our developed PCR melting curve analysis offers accurate, reliable, rapid, simple, and cost-effective detection of DPYD and UGT1A1 polymorphisms. Its application can be easily extended to clinical laboratories equipped with a fluorescent PCR platform. [ABSTRACT FROM AUTHOR]

Irinotecan (also known as CPT-11) is a topoisomerase I inhibitor first approved for clinical use as an anticancer agent in 1996. Over the past more than two decades, it has been widely used for combination regimens to treat various malignancies, especially in gastrointestinal and lung cancers. However, severe dose-limiting toxicities, especially gastrointestinal toxicity such as late-onset diarrhea, were frequently observed in irinotecan-based therapy, thus largely limiting the clinical application of this agent. Current knowledge regarding the pathogenesis of irinotecan-induced diarrhea is characterized by the complicated metabolism of irinotecan to its active metabolite SN-38 and inactive metabolite SN-38G. A series of enzymes and transporters were involved in these metabolic processes, including UGT1A1 and CYP3A4. Genetic polymorphisms of these metabolizing enzymes were significantly associated with the occurrence of irinotecan-induced diarrhea. Recent discoveries and progress made on the detailed mechanisms enable the identification of potential biomarkers for predicting diarrhea and as such guiding the proper patient selection with a better range of tolerant dosages. In this review, we introduce the metabolic process of irinotecan and describe the pathogenic mechanisms underlying irinotecan-induced diarrhea. Based on the mechanisms, we further outline the potential biomarkers for predicting the severity of diarrhea. Finally, based on the current experimental evidence in preclinical and clinical studies, we discuss and prospect the current and emerging strategies for the prevention of irinotecan-induced diarrhea. [ABSTRACT FROM AUTHOR]

Bilirubin-induced neurological damage (BIND), which might progress to kernicterus, occurs as a consequence of defects in the bilirubin conjugation machinery, thus enabling albumin-unbound free bilirubin (BF) to cross the blood–brain barrier and accumulate within. A defect in the UGT1A1 enzyme-encoding gene, which is directly responsible for bilirubin conjugation, can cause Crigler–Najjar syndrome (CNS) and Gilbert’s syndrome. We used human-induced pluripotent stem cell (hiPSC)-derived 3D brain organoids to model BIND in vitro and unveil the molecular basis of the detrimental effects of BF in the developing human brain. Healthy and patient-derived iPSCs were differentiated into day-20 brain organoids, and then stimulated with 200 nM BF. Analyses at 24 and 72 h post-treatment point to BF-induced neuro-inflammation in both cell lines. Transcriptome, associated KEGG, and Gene Ontology analyses unveiled the activation of distinct inflammatory pathways, such as cytokine–cytokine receptor interaction, MAPK signaling, and NFκB activation. Furthermore, the mRNA expression and secretome analysis confirmed an upregulation of pro-inflammatory cytokines such as IL-6 and IL-8 upon BF stimulation. This novel study has provided insights into how a human iPSC-derived 3D brain organoid model can serve as a prospective platform for studying the etiology of BIND kernicterus.