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Melphalan is a bifunctional alkylating agent that elicits its cytotoxic activity by rapidly forming an initial DNA monoadduct, which then produces an inter-strand crosslink. Most studies exploring the role of inherited differences in DNA repair and melphalan outcomes focus on inter-strand crosslink repair, however, monoadduct repair likely plays a key role since it minimises the ultimate production of these crosslinks. The purpose of this systematic review was to assess evidence of an association between variation in monoadduct repair pathways and melphalan response. A literature search was undertaken using Medline, Embase, Scopus and PubMed databases. Duplicates were removed and only full-text articles were included. To be included for critique in this systematic review, articles were assessed for relevance using strict inclusion/exclusion criteria. Fourteen studies were identified that involved patients treated with melphalan, however, in 3, only a minority of the cohort received melphalan. Across the remaining 11 studies, 61 genes/proteins in DNA monoadduct repair pathways were assessed. Both germline SNP (CDKN1A, ERCC1, ERCC2, ERCC4, ERCC6, EXO1, MLH1, MNAT1, MUTYH, PARP4, PCNA, POLE, POLR1G, RAD23B, RFC1, RFC3, RPA1, RPA3, TREX1, UNG, XPC, XRCC1) and somatic expression (CDKN1A, PARP1, PCNA, MGMT, RECQL, RFC5) were associated with melphalan outcomes in ≥ 1 study. It appears that inherited germline differences in monoadduct repair genes may be a risk factor for poor outcomes. However, the diversity of study design, patient cohorts, genes assessed and lack of replication, preclude any meta-analysis. Further prospective studies are required to validate these findings.

The study objective is to analyze the mutation profile of the tall cell variant (TCV) of papillary thyroid carcinoma (PTC).Materials and methods. The main inclusion criteria according to the WHO classification (2017) was PTC composed of at least 30 % of tall cells. Genetic examination was conducted using the FoundationOne CDx assay (USA) with median depth of coverage of >500x. This study included 5 patients (1 man and 4 women) with a mean age of 52.6 years (range: 48-56 years). The tumor size varied between 0.4 x 0.5 cm and 11.0 x 9.0 cm. All patients have undergone surgical treatment: hemithyroidectomy for patient No. 1 with a small tumor (pT1b); thyroidectomy for patient No. 2 (pT3b); extensive thyroidectomy with the removal of paratracheal tissue for patients No. 3, 4, and 5 (No. 3 - pT3bN0; No. 4 - pT3bN1b; No. 5 - pT3bN1b). Three out of the five patients also had adenomatous goiter. The mean follow-up time was 3.4 to 5.2 years.Results. Tumors in all patients were characterized by low mutational load (0 to 4 mutations per 1 million nucleotides (megabase)) and no microsatellite instability. All study participants were found to have p.V600E mutation in the BRAF gene; two patients had c.-124C>T mutation in the promoter region of the TERT gene. All patients carried mutations with unknown clinical significance: p.V562I in the EPHB1 gene (in 2 patients); mutations in the genes AR, CREBBP, EP300, ERCC4, FLT1, IKBKE, JAK2, MAF, MLL2, MST1R, MYC, MYCL1, NTRK2, TSC2 (each mutation registered in one patient). One individual with the largest tumor and the most aggressive disease was found to have amplifications of the BTG2, MAP3K1, SMAD2, and TBX3 genes.Conclusion. In 5 patients analyzed in this study, the mutation profile of TCV PTC was characterized by low mutational load, no microsatellite instability, and presence of p.V600E mutation in the BRAF gene in all cases. Some patients also had c.-124C>T mutation in the TERT gene and p.V562I mutation in the EPHB1 gene.

Purpose Oxaliplatin forms part of routine treatment of advanced colorectal cancer; however, it often causes severe peripheral neuropathy, resulting in treatment discontinuation. We sought to determine the molecular and cellular mechanism underlying this toxicity. Patients and Methods We exome resequenced blood DNA samples from nine patients with advanced colorectal cancer who had severe peripheral neuropathy associated with oxaliplatin (PNAO) within 12 weeks of treatment. We Sanger sequenced the ERCC4 and ERCC6 open reading frames in 63 patients with PNAO and carried out targeted genotyping in 1,763 patients without PNAO. We tested the functionality of ERCC4 variants using viability and DNA repair assays in Schizosaccharomyces pombe and human cell lines after exposure to oxaliplatin and ultraviolet light. Results Exome resequencing identified one patient carrying a novel germline truncating mutation in the nucleotide excision repair (NER) gene ERCC4. This mutation was functionally associated with sensitivity to oxaliplatin ( P = 3.5 × 10−2). We subsequently found that multiple rare ERCC4 nonsynonymous variants were over-represented in affected individuals ( P = 7.7 × 10−3) and three of these were defective in the repair of ultraviolet light–induced DNA damage ( P < 1 × 10−3). We validated a role for NER genes in PNAO by finding that multiple rare ERCC6 nonsynonymous variants were similarly over-represented in affected individuals ( P = 2.4 × 10−8). Excluding private variants, 22.2% of patients (14 of 63 patients) with PNAO carried Pro379Ser or Glu875Gly in ERCC4 or Asp425Ala, Gly446Asp, or Ser797Cys in ERCC6, compared with 8.7% of unaffected patients (152 of 1,750 patients; odds ratio, 3.0; 95% CI, 1.6 to 5.6; P = 2.5 × 10−4). Conclusion Our study provides evidence for a role of NER genes in PNAO, together with mechanistic insights.

The ERCC4/FANCQ gene is a potential candidate gene for susceptibility to hereditary breast cancer, being a participant of the Fanconi anemia (FA)/BRCA pathway required for DNA repair. ERCC4 encodes XPF endonuclease which mainly participates in nucleotide excision repair (NER) and interstrand crosslink (ICL) repair. Heterozygous mutations in ERCC4 have been identified in various cancers. In this study the heterozygous mutation c.2395C>T (p.Arg799Trp) in ERCC4 was found in a hereditary breast cancer patient using next-generation sequencing. Further screening for the ERCC4*p.Arg799Trp mutation in 966 breast cancer patients and 686 control individuals revealed heterozygous mutation carriers in both groups, but no statistically significant differences in the frequency of the mutant allele between the two samples were found. The results of our study suggest that the ERCC4*p.Arg799Trp mutation is not associated with high risk of breast cancer, although further studies are needed to evaluate the clinical significance of this mutation.

Reactive oxygen species formation and resultant oxidative damage to DNA are ubiquitous events in cells, the homeostasis of which can be dysregulated in a range of pathological conditions. Base excision repair (BER) is the primary repair mechanism for oxidative genomic DNA damage. One prevalent oxidised base modification, 8-oxoguanine (8-oxoG), is recognised by 8-oxoguanine glycosylase-1 (OGG1) initiating removal and repair via BER. Surprisingly, Ogg1 null mouse embryonic fibroblasts (mOgg1−/− MEFs) do not accumulate 8-oxoG in the genome to the extent expected. This suggests that there are backup repair mechanisms capable of repairing 8-oxoG in the absence of OGG1. In the current study, we identified components of NER (Ercc1, Ercc4, Ercc5), BER (Lig1, Tdg, Nthl1, Mpg, Mgmt, NEIL3), MMR (Mlh1, Msh2, Msh6) and DSB (Brip1, Rad51d, Prkdc) pathways that are transcriptionally elevated in mOgg1−/− MEFs. Interestingly, all three nucleotide excision repair genes identified: Ercc1 (2.5 ± 0.2-fold), Ercc4 (1.5 ± 0.1-fold) and Ercc5 (1.7 ± 0.2-fold) have incision activity. There was also a significant functional increase in NER activity (42.0 ± 7.9%) compared to WT MEFs. We also observed upregulation of both Neil3 mRNA (37.9 ± 1.6-fold) and protein in mOgg1−/− MEFs. This was associated with a 3.4 ± 0.4-fold increase in NEIL3 substrate sites in genomic DNA of cells treated with BSO, consistent with the ability of NEIL3 to remove 8-oxoG oxidation products from genomic DNA. In conclusion, we suggest that in Ogg1-null cells, upregulation of multiple DNA repair proteins including incision components of the NER pathway and Neil3 are important compensatory responses to prevent the accumulation of genomic 8-oxoG.

Colorectal cancer (CRC) incidence in young adults is rising. Identifying genetic risk factors is fundamental for the clinical management of patients and their families. This study aimed to identify clinically significant germline variants among young adults with CRC. Whole-exome sequencing data of blood-derived DNA from 133 unrelated young CRC patients (

Xeroderma Pigmentosum (XP) is a rare genetic disorder affecting the nucleotide excision repair system (NER). It is characterized by an extreme sensitivity to sunlight that induces cutaneous disorders such as severe sunburn, freckling and cancers. In Tunisia, six complementation groups have been already identified. However, the genetic etiology remains unknown for several patients. In this study, we investigated clinical characteristics and genetic defects in two families with atypical phenotypes originating from the central region in Tunisia. Clinical investigation revealed mild cutaneous features in two patients who develop multiple skin cancers at later ages, with no neurological disorders. Targeted gene sequencing revealed that they carried novel variants. A homozygous variation in the ERCC4 gene c.1762G>T, p.V588F, detected in patient XP21. As for patient XP134, he carried two homozygous mutations in the DDB2 gene c.613T>C, p.C205R and c.618C>A, p.S206R. Structural modeling of the protein predicted the identified ERCC4 variant to mildly affect protein stability without affecting its functional domains. As for the case of DDB2 double mutant, the second variation seems to cause a mild effect on the protein structure unlike the first variation which does not seem to have an effect on it. This study contributes to further characterize the mutation spectrum of XP in Tunisian families. Targeted gene sequencing accelerated the identification of rare unexpected genetic defects for diagnostic testing and genetic counseling.

PurposeTo investigate the impact of genetic variants of DNA repair and pro-fibrotic pathway genes on the severity of radiation-induced subcutaneous fibrosis in patients of oropharyngeal carcinoma treated with radical radiotherapy.Materials and MethodsPatients of newly diagnosed squamous cell carcinoma of oropharynx being treated with two-dimensional radical radiotherapy were enrolled in the study. Patients who had undergone surgery or were receiving concurrent chemotherapy were excluded. Patients were followed up at 6 weeks post completion of radiotherapy and every 3 months thereafter for a median of 16 months. Subcutaneous fibrosis was graded according to the Radiation Therapy Oncology Group (RTOG) and the European Organization for Research and Treatment of Cancer (EORTC) grading system and the maximum grade was recorded over the length of the patient’s follow-up. Patients with severe fibrosis (≥G3), were compared to patients with minor (≤G2) fibrotic reactions. Eight single nucleotide polymorphisms of 7 DNA repair genes and 2 polymorphisms of a single pro-fibrotic pathway gene were analyzed by Polymerase Chain Reaction and Restriction Fragment Length Polymorphism and were correlated with the severity of subcutaneous fibrosis.Results179 patients were included in the analysis. Subcutaneous fibrosis was seen in 168 (93.9%) patients. 36 (20.1%) patients had severe (grade 3) fibrosis. On multivariate logistic regression analysis, Homozygous CC genotype of XRCC3 (722C>T, rs861539) (p=0.013*, OR 2.350, 95% CI 1.089-5.382), Homozygous AA genotype of ERCC4 Ex8 (1244G>A, rs1800067) (p=0.001**, OR 11.626, 95% CI 2.490-275.901) and Homozygous TT genotype of XRCC5 (1401G>T, rs828907) (p=0.020*, OR 2.188, 95% CI 1.652-7.334) were found to be predictive of severe subcutaneous fibrosis. On haplotype analysis, the cumulative risk of developing severe fibrosis was observed in patients carrying both haplotypes of variant Homozygous AA genotype of ERCC4 Ex8 (1244G>A, rs1800067) and Homozygous TT genotype of XRCC5 (1401 G>T, rs828907) (p=0.010*, OR 26.340, 95% CI 4.014-76.568).ConclusionWe demonstrated significant associations between single nucleotide polymorphisms of DNA repair genes and radiation-induced subcutaneous fibrosis in patients of oropharyngeal carcinoma treated with radiotherapy. We propose to incorporate these genetic markers into predictive models for identifying patients genetically predisposed to the development of radiation-induced fibrosis, thus guiding personalized treatment protocols.

Cell-free DNA (cfDNA) is described to mirror intratumoral heterogeneity and gives insight about clonal evolution for improved therapeutic decisions. We sequenced cfDNA of a hormone receptor-positive, HER2-negative metastatic breast cancer (MBC) cohort with a high coverage to examine the prevalence and relevance of any detected variant. cfDNA of 44 MBC patients was isolated, followed by library construction using a customized targeted DNA panel with integrated unique molecular indices analyzing AKT1, AR, BRCA1, BRCA2, EGFR, ERCC4, ERBB2, ERBB3, ESR1, FGFR1, KRAS, MUC16, PIK3CA, PIK3R1, PTEN, PTGFR, and TGFB1. CfDNA was sequenced on the NextSeq® 550 platform (Illumina) and variants were analyzed with Ingenuity Variant Analysis (QIAGEN). We evaluated cfDNA variants in 40 of the 44 hormone receptor-positive and HER2-negative patients with a high mean coverage of 22,000×, resulting in MUC16, BRCA2, ERBB3, and AR variant calling in > 90% of the patients. 47% of all AR variants were pathogenic and at least one pathogenic or likely pathogenic variant was detected in each patient. A specific BRCA1 variant and > 3.5 pathogenic variants significantly associated with a reduced survival after diagnosis of metastasis. Longitudinal monitoring revealed an increase of pathogenic and likely pathogenic PIK3CA and ESR1 variant allele frequency under everolimus and exemestane, 8 months before proof of therapy failure by visual staging in one exemplary case. The identification of new variants with high prevalence, prognostic value, and dynamics under treatment by deep sequencing of cfDNA might empower sensitive monitoring and personalized therapeutic decisions. Electronic supplementary material The online version of this article (10.1007/s00018-019-03189-z) contains supplementary material, which is available to authorized users.

Nucleotide excision repair (NER) is an essential DNA repair pathway devoted to the removal of bulky lesions such as photoproducts induced by the ultraviolet (UV) component of solar radiation. Deficiencies in NER typically result in a group of heterogeneous distinct disorders ranging from the mild UV sensitive syndrome to the cancer-prone xeroderma pigmentosum and the neurodevelopmental/progeroid conditions trichothiodystrophy, Cockayne syndrome and cerebro-oculo-facio-skeletal-syndrome. A complicated genetic scenario underlines these disorders with the same gene linked to different clinical entities as well as different genes associated with the same disease. Overlap syndromes with combined hallmark features of different NER disorders can occur and sporadic presentations showing extra features of the hematological disorder Fanconi Anemia or neurological manifestations mimicking Hungtinton disease-like syndromes have been described. Here, we discuss the multiple functions of the five major pleiotropic NER genes (ERCC3/XPB, ERCC2/XPD, ERCC5/XPG, ERCC1 and ERCC4/XPF) and their relevance in phenotypic complexity. We provide an update of mutational spectra and examine genotype-phenotype relationships. Finally, the molecular defects that could explain the puzzling overlap syndromes are discussed.

Lu Yang,1,* Ming Xu,2,* Chuan-Bao Cui,1 Peng-Hai Wei,1 Shu-Zhi Wu,1 Zuo-Jie Cen,1 Xing-Xing Meng,1 Qiong-Guang Huang,1 Zhi-Chun Xie1 1Department of Epidemiology, Guangxi Medical University, Nanning 530021, Guangxi Zhuang Autonomous Region, People’s Republic of China; 2Department of Human Anatomy and Histology and Embryology, Qilu Medical University, Zibo 255213, Shandong Province, People’s Republic of China *These authors contributed equally to this work Background: The current study aims at using the whole genome expression profile chips for systematically investigating the diagnostic and prognostic values of excision repair cross-complementation (ERCC) genes in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC).Materials and methods: Whole genome expression profile chips were obtained from the GSE14520. The receiver-operating characteristic (ROC) curve, survival analysis, and nomogram were used to investigate the diagnostic and prognostic values of ERCC genes. Investigation of the potential function of ERCC8 was carried out by gene set enrichment analysis (GSEA) and genome-wide coexpression analysis.Results: ROC analysis suggests that six ERCC genes (ERCC1, ERCC2, ERCC3, ERCC4, ERCC5, and ERCC8) were dysregulated and may have potential to distinguish between HBV-related HCC tumor and paracancerous tissues (area under the curve of ROC ranged from 0.623 to 0.744). Survival analysis demonstrated that high ERCC8 expression was associated with a significantly decreased risk of recurrence (adjusted P=0.021; HR=0.643; 95% CI=0.442–0.937) and death (adjusted P=0.049; HR=0.631; 95% CI=0.399–0.998) in HBV-related HCC. Then, we also developed two nomograms for the HBV-related HCC individualized prognosis predictions. GSEA suggests that the high expression of ERCC8 may have involvement in the energy metabolism biological processes. As the genome-wide coexpression analysis and functional assessment of ERCC8 suggest, those coexpressed genes were significantly enriched in multiple biological processes of DNA damage and repair. Conclusion: The present study indicates that six ERCC genes (ERCC1, ERCC2, ERCC3, ERCC4, ERCC5, and ERCC8) were dysregulated between HBV-related HCC tumor and paracancerous tissues and that the mRNA expression of ERCC8 may serve as a potential biomarker for the HBV-related HCC prognosis. Keywords: HBV, hepatocellular carcinoma, diagnosis, prognosis, ERCC

Purpose: Gallbladder cancer (GBC) is the most aggressive tumor of the biliary tract. Since DNA damage is one of the common events in GBC, we hypothesized that nucleotide excision repair enzymes may be defective in GBC. We aimed to investigate the association of SNP rs1800067 (G/A) of ERCC4 with the disease predisposition in gallbladder cancer and its prognosis. We have also investigated the expression of ERCC4 in GBC patients and gallstone patients for any possible correlation with the SNP.Methods: In 350 GBC patients and 300 controls, ERCC4 SNP rs1800067 was genotyped by PCR-RFLP. Semi-quantitative RT-PCR was performed using ERCC4 and internal control β-actin primers in gallstone and tumor biopsy. We adopted the Kaplan-Meier plot and log-rank tests to explore the association of rs1800067 and prognosis of gallbladder cancer patients. Results: We demonstrate that the minor allele A is less frequent in GBC patients than healthy controls, suggesting the association of GA genotype with decreased risk of GBC. rs1800067 genotypes have significantly differential frequencies relative to clinical parameters. The relative expression of ERCC4 is significantly differentially expressed among early and late stages of tumors. Patients with combined GA+AA genotypes had longer overall survival in patients with early stages of tumors and with chemotherapy.Conclusion: Our results suggest that minor allele A is significantly associated with reduced risk of gallbladder carcinogenesis. The upregulation of relative mRNA expression of ERCC4 is an early event in the progression of gallbladder cancer.

Resistance to adjuvant chemotherapy is a major clinical problem in the treatment of colorectal cancer (CRC). The aim of this study was to elucidate the role of an epithelial to mesenchymal transition (EMT)‐inducing protein, ZEB2, in chemoresistance of CRC, and to uncover the underlying mechanism. We performed IHC for ZEB2 and association analyses with clinical outcomes on primary CRC and matched CRC liver metastases in compliance with observational biomarker study guidelines. ZEB2 expression in primary tumours was an independent prognostic marker of reduced overall survival and disease‐free survival in patients who received adjuvant FOLFOX chemotherapy. ZEB2 expression was retained in 96% of liver metastases. The ZEB2‐dependent EMT transcriptional programme activated nucleotide excision repair (NER) pathway largely via upregulation of the ERCC1 gene and other components in NER pathway, leading to enhanced viability of CRC cells upon oxaliplatin treatment. ERCC1‐overexpressing CRC cells did not respond to oxaliplatin in vivo, as assessed using a murine orthotopic model in a randomised and blinded preclinical study. Our findings show that ZEB2 is a biomarker of tumour response to chemotherapy and risk of recurrence in CRC patients. We propose that the ZEB2‐ERCC1 axis is a key determinant of chemoresistance in CRC., Here, we show that the expression of ZEB2 marks reduced overall and disease‐free survival in primary and secondary colorectal cancers (CRCs). ZEB2 overexpression promoted chemoresistance to oxaliplatin in vitro and in vivo by transcriptionally activating nucleotide excision repair genes ERCC1 and ERCC4. Overall ZEB2 is a promising biomarker predicting both therapy response and metastatic ability of CRCs.

Background Multiple studies around the world revealed that genetic polymorphism in different genes of the DNA repair system might affect the DNA repair capabilities and accelerate the chances of cervical cancer (CC) development. Therefore, we aimed to evaluate the association of DNA repair gene- ECCR1 rs11615, ERCC4 rs2276466, XPC rs2228000 and rs2228001 polymorphisms and CC susceptibility in the Bangladeshi population. Methods A case-control genetic association study was conducted among 210 patients with diagnostically confirmed CC and 200 healthy volunteers. The p-value and OR (odds ratios) with 95% CI (confidence interval) were evaluated to get the level of association. Results After the individual analysis of all SNPs, we noticed that ECCR1 rs11615 possessed a significantly lower risk, whereas ERCC4 rs2276466 possessed a significantly elevated risk of CC in all genetic models (p < 0.05). XPC rs2228000 showed a significantly lower risk of CC in TC, TC + CC genotypes and allele model (OR = 0.61, p = 0.025; OR = 0.61, p = 0.019 and OR = 0.67, p = 0.027, respectively), whereas XPC rs2228001 possessed a significantly elevated risk of CC in CA, CA + AA genotypes and allele model (OR = 1.67, p = 0.012; OR = 1.69, p = 0.009 and OR = 1.42, p = 0.022). Besides, ERCC4 rs2276466 (Grade III vs. I + II: OR = 4.01, p = 0.003) and XPC rs2228001 (Grade III vs. I + II: OR = 3.38, p = 0.003) were connected with high tumor aggressiveness and ERCC4 rs2276466 was also showed a lower risk of CC development in the younger population (, Cervical cancer, Single nucleotide polymorphism, ECCR1, ERCC4, XPC, Bangladeshi ethnicity.

Acute myeloid leukemia (AML) is one of the most common types of leukemia. With the recent advances in sequencing technology and the growing body of knowledge on the genetics of AML, there is increasing concern about cancer predisposing germline mutations as well as somatic mutations. As familial cases sharing germline mutations are constantly reported, germline predisposition gene mutations in patients with AML are gaining attention. We performed genomic sequencing of Korean patients diagnosed with AML to identify the prevalence and characteristics of germline predisposition mutations. Among 180 patients, germline predisposition mutations were identified in 13 patients (13/180, 7.2%, eight adults and five children). Germline mutations of BLM, BRCA1, BRCA2, CTC1, DDX41, ERCC4, ERCC6, FANCI, FANCM, PALB2, and SBDS were identified. Most of the mutations are in genes involved in DNA repair and genomic stability maintenance. Patients harboring germline mutations tended to have earlier onset of AML (p = 0.005), however, the presence of germline mutations did not showed significant association with other clinical characteristics or treatment outcome. Since each mutation was rare, further study with a larger number of cases would be needed to establish the effect of the mutations.

The repair of protein-linked chromosomal breaks requires distinct factors throughout the life span., Deficiency in the DNA end-processing enzyme, tyrosyl-DNA phosphodiesterase 1 (TDP1), causes progressive neurodegeneration in humans. Here, we generated a tdp1 knockout zebrafish and confirmed the lack of TDP1 activity. In adulthood, homozygotes exhibit hypersensitivity to topoisomerase 1 (Top1) poisons and a very mild locomotion defect. Unexpectedly, embryonic tdp1−/− zebrafish were not hypersensitive to Top1 poisons and did not exhibit increased Top1-DNA breaks. This is in contrast to the hypersensitivity of Tdp1-deficient vertebrate models reported to date. Tdp1 is dispensable in the zebrafish embryo with transcript levels down-regulated in response to Top1-DNA damage. In contrast, apex2 and ercc4 (xpf) transcripts were up-regulated. These findings identify the tdp1−/− zebrafish embryo as the first vertebrate model that does not require Tdp1 to protect from Top1-DNA damage and identify apex2 and ercc4 (xpf) as putative players fulfilling this role. It highlights the requirement of distinct DNA repair factors across the life span of vertebrates.

Chronic kidney disease (CKD) patients have many affected physiological pathways. Variations in the genes regulating these pathways might affect the incidence and predisposition to this disease. A total of 722 Spanish adults, including 548 patients and 174 controls, were genotyped to better understand the effects of genetic risk loci on the susceptibility to CKD. We analyzed 38 single nucleotide polymorphisms (SNPs) in candidate genes associated with the inflammatory response (interleukins IL-1A, IL-4, IL-6, IL-10, TNF-α, ICAM-1), fibrogenesis (TGFB1), homocysteine synthesis (MTHFR), DNA repair (OGG1, MUTYH, XRCC1, ERCC2, ERCC4), renin-angiotensin-aldosterone system (CYP11B2, AGT), phase-II metabolism (GSTP1, GSTO1, GSTO2), antioxidant capacity (SOD1, SOD2, CAT, GPX1, GPX3, GPX4), and some other genes previously reported to be associated with CKD (GLO1, SLC7A9, SHROOM3, UMOD, VEGFA, MGP, KL). The results showed associations of GPX1, GSTO1, GSTO2, UMOD, and MGP with CKD. Additionally, associations with CKD related pathologies, such as hypertension (GPX4, CYP11B2, ERCC4), cardiovascular disease, diabetes and cancer predisposition (ERCC2) were also observed. Different genes showed association with biochemical parameters characteristic for CKD, such as creatinine (GPX1, GSTO1, GSTO2, KL, MGP), glomerular filtration rate (GPX1, GSTO1, KL, ICAM-1, MGP), hemoglobin (ERCC2, SHROOM3), resistance index erythropoietin (SOD2, VEGFA, MTHFR, KL), albumin (SOD1, GSTO2, ERCC2, SOD2), phosphorus (IL-4, ERCC4 SOD1, GPX4, GPX1), parathyroid hormone (IL-1A, IL-6, SHROOM3, UMOD, ICAM-1), C-reactive protein (SOD2, TGFB1,GSTP1, XRCC1), and ferritin (SOD2, GSTP1, SLC7A9, GPX4). To our knowledge, this is the second comprehensive study carried out in Spanish patients linking genetic polymorphisms and CKD.

AR-V7-expressing metastatic prostate cancer is an aggressive phenotype with poor progression-free survival (PFS) and overall survival (OS). Preliminary evidence suggests that AR-V7-positive tumors may be enriched for DNA-repair defects, perhaps rendering them more sensitive to immune-checkpoint blockade. We enrolled 15 metastatic prostate cancer patients with AR-V7-expressing circulating tumor cells into a prospective phase-2 trial. Patients received nivolumab 3 mg/kg plus ipilimumab 1 mg/kg every 3 weeks for four doses, then maintenance nivolumab 3 mg/kg every 2 weeks. Targeted next-generation sequencing was performed to determine DNA-repair deficiency (DRD) status. Outcomes included PSA response rates, objective response rates (ORR), PSA progression-free survival (PSA-PFS), clinical/radiographic PFS and OS. Median age of participants was 65, median PSA was 115 ng/mL, 67% had visceral metastases, and 60% had ≥4 prior systemic therapies. Six of 15 men (40%) had DRD mutations (three in BRCA2, two in ATM, one in ERCC4; none had microsatellite instability). Overall, the PSA response rate was 2/15 (13%), ORR was 2/8 (25%) in those with measurable disease, median PSA-PFS was 3.0 (95%CI 2.1–NR) months, PFS was 3.7 (95%CI 2.8–7.5) months, and OS was 8.2 (95%CI 5.5–10.4) months. Outcomes appeared generally better in DRD+ vs. DRD– tumors with respect to PSA responses (33% vs. 0%; P=0.14, nonsignificant), ORR (40% vs. 0%; P=0.46, nonsignificant), PSA-PFS (HR 0.19; P

Purpose Some previous studies have sought to investigate the roles of excision repair cross complementation group 1 (ERCC1), ERCC2, ERCC4, and ERCC5 gene polymorphisms in the prognosis of osteosarcoma patients. However, their results were inconclusive. Here, we performed a meta-analysis to determine the strength of the association between eight polymorphisms in the ERCC genes (rs11615, rs3212986, rs2298881, rs13181, rs1799793, rs1800067, rs2296147, and rs1047768) and prognosis of osteosarcoma patients treated with chemotherapy. Materials and methods We retrieved the relevant studies from PubMed, Embase, and Web of Science in human osteosarcoma published prior to July 2017. Primary outcomes included overall survival (OS) and event-free survival, expressed by hazard ratios (HRs) with their corresponding 95% CIs. STATA software (version 12.0) was utilized to perform data synthesis. Results A total of 13 eligible follow-up studies involving 2,303 patients met all the inclusion criteria, conducted in two populations of ethnic descent: 11 Asians and two Caucasians. In the present meta-analysis, we demonstrated that the homozygous variant genotypes in ERCC2 rs1799793 and ERCC5 rs2296147 were significantly associated with OS in osteosarcoma (TT vs GG for rs1799793: HR = 0.62, 95% CI = 0.41-0.93, Pheterogeneity = 0.310, I2 = 15.3%, P = 0.020; TT vs CC for rs2296147: HR = 0.42, 95% CI = 0.23-0.78, Pheterogeneity = 0.708, I2 = 0.0%, P = 0.006). In addition, no evidence of association was observed between prognosis in osteosarcoma and ERCC1 rs11615, ERCC1 rs3212986, ERCC1 rs2298881, ERCC2 rs13181, ERCC4 rs1800067, and ERCC5 rs1047768 polymorphisms. Conclusion Our meta-analysis indicated that TT genotype in the ERCC2 rs1799793 and ERCC5 rs2296147 might prolong the survival time of patients with osteosarcoma, suggesting that the rs1799793 and rs2296147 polymorphisms can be used as predictors for prognosis of osteosarcoma patients treated with chemotherapy.

BACKGROUND: Exposure to particulate air pollution has been linked with risk of carcinogenesis. Damage to repair pathways might have long-term adverse health effects. We aimed to investigate the association of prenatal exposure to air pollution with placental mutation rate and the DNA methylation of key placental DNA repair genes. METHODS: This cohort study used data from the ongoing ENVironmental Influence ON early AGEing (ENVIRONAGE) birth cohort, which enrols pairs of mothers and neonates (singleton births only) at the East-Limburg Hospital (Genk, Belgium). Placental DNA samples were collected after birth. We used bisulfite-PCR-pyrosequencing to investigate the mutation rate of Alu (a marker for overall DNA mutation) and DNA methylation in the promoter genes of key DNA repair and tumour suppressor genes (APEX1, OGG1, PARP1, ERCC1, ERCC4, p53, and DAPK1). We used a high-resolution air pollution model to estimate exposure to particulate matter with a diameter less than 2·5 μm (PM2·5), black carbon, and NO2 over the entire pregnancy on the basis of maternal address. Alu mutation was analysed with a linear regression model, and methylation values of the selected genes were analysed in mixed-effects models. Effect estimates are presented as the relative percentage change in methylation for an ambient air pollution increment of one IQR (ie, the difference between the first and third quartiles of exposure in the entire cohort). FINDINGS: 500 biobanked placental DNA samples were randomly selected from 814 pairs of mothers and neonates who were recruited to the cohort between Feb 1, 2010, and Dec 31, 2014, of which 463 samples met the pyrosequencing quality control criteria. IQR exposure increments were 3·84 μg/m3 for PM2·5, 0·36 μg/m3 for black carbon, and 5·34 μg/m3 for NO2. Among these samples, increased Alu mutation rate was associated with greater exposure to PM2·5 (r=0·26, p

Jing He,1,* Zhen-Jian Zhuo,2,* Anqi Zhang,3,* Jinhong Zhu,4 Rui-Xi Hua,5 Wen-Qiong Xue,1 Shao-Dan Zhang,1 Jiang-Bo Zhang,1 Xi-Zhao Li,1 Wei-Hua Jia1 1State Key Laboratory of Oncology in South China, Department of Experimental Research, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, China; 2Faculty of Medicine, School of Chinese Medicine, The Chinese University of Hong Kong, Hong Kong, China; 3Department of Obstetrics and Gynecology, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; 4Molecular Epidemiology Laboratory, Department of Laboratory Medicine, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China; 5Department of Oncology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China *These authors contributed equally to this work Background: Potentially functional polymorphisms can modulate protein activities and host’s DNA repair capacity, thereby influencing cancer susceptibility. The association of the polymorphisms in the nucleotide excision repair core pathway genes and gastric cancer susceptibility remains largely unknown. Methods: Here, we systematically analyzed the associations between nine polymorphisms in four key genes (XPA, ERCC1, ERCC2, and ERCC4) in the nucleotide excision repair pathway and gastric cancer risk in a Chinese population including 1142 patients and 1173 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to estimate the risk associations. Results: We observed that ERCC1 rs2298881 CA variant genotype was associated with an increased gastric cancer risk (CA vs. CC: adjusted OR [AOR]=1.33, 95% CI=1.09–1.62; dominant model: AOR=1.32, 95% CI=1.10–1.60). However, ERCC1 rs3212986 AA variant genotype was identified as a protective factor for gastric cancer (AA vs. CC: AOR=0.73, 95% CI=0.54–0.98; recessive model: AOR=0.72, 95% CI=0.54–0.96). Genotype-based mRNA expression analysis further indicated that the rs2298881 A allele was associated with decreased ERCC1 mRNA expression. Conclusion: In all, these results indicated that the ERCC1 polymorphisms may affect the risk of gastric cancer in the Chinese Han population. Keywords: gastric cancer, DNA repair, NER, polymorphism, susceptibility

Autosomal recessive cerebellar ataxias (ARCAs) are clinically and genetically heterogeneous neurological disorders. Through whole-exome sequencing of Japanese ARCA patients, we identified three index patients from unrelated families who had biallelic mutations in ERCC4. ERCC4 mutations have been known to cause xeroderma pigmentosum complementation group F (XP-F), Cockayne syndrome, and Fanconi anemia phenotypes. All of the patients described here showed very slowly progressive cerebellar ataxia and cognitive decline with choreiform involuntary movement, with young adolescent or midlife onset. Brain MRI demonstrated atrophy that included the cerebellum and brainstem. Of note, cutaneous symptoms were very mild: there was normal to very mild pigmentation of exposed skin areas and/or an equivocal history of pathological sunburn. However, an unscheduled DNA synthesis assay of fibroblasts from the patient revealed impairment of nucleotide excision repair. A similar phenotype was very recently recognized through genetic analysis of Caucasian cerebellar ataxia patients. Our results confirm that biallelic ERCC4 mutations cause a cerebellar ataxia-dominant phenotype with mild cutaneous symptoms, possibly accounting for a high proportion of the genetic causes of ARCA in Japan, where XP-F is prevalent.

Excision repair cross-complementing (ERCC) genes, key components of the nucleotide excision repair pathway, are regarded as crucial factors for DNA repair capacity. Previous studies have investigated prognostic values of ERCC genes in a number of malignancies. However, the relationship between ERCC genes and prognosis of ovarian cancer patients remains controversial. Therefore, in the current study, we systematically analyze the prognostic values of ERCC genes in ovarian cancer by the Kaplan-Meier plotter, which includes updated gene expression data and survival information of 1656 ovarian cancer patients. Our results showed that high expression of ERCC1 and ERCC8 mRNA was related to a worse overall survival among ovarian cancer patients, especially in late stage and poor differentiation serous ovarian patients. Increased ERCC4 mRNA expression indicated a better overall survival among serous ovarian cancer patients. The other ERCC genes were uncorrelated with prognosis in ovarian cancer. These results indicate that some ERCC genes have critical prognostic values in ovarian cancer.

Platinum-based chemotherapy (PBC) in combination with the 3rd generation drugs is the first-line treatment for patients with advanced non-small cell lung cancer (NSCLC); however, the efficacy is severely hampered by grade 3-4 toxicities. Nucleotide excision repair (NER) pathway is the main mechanism of removing platinum-induced DNA adducts that contribute to the toxicity and outcome of PBC. We analyzed data from 710 Chinese NSCLC patients treated with PBC and assessed the associations of 25 potentially functional single nucleotide polymorphisms (SNPs) in nine NER core genes with overall, gastrointestinal and hematologic toxicities. Through a two-phase study, we found that ERCC4 rs1799798 was significantly associated with overall and gastrointestinal toxicities [all patients: GA/AA vs. GG, odds ratio (OR)adj =1.61 and 2.35, 95% confidence interval (CI)=1.11-2.33 and 1.25-4.41, and Padj =0.012 and 0.008, respectively]. Our prediction model for the overall toxicity incorporating rs1799798 demonstrated a significant increase in the area under the curve (AUC) value, compared to that for clinical factors only (all patients: AUC = 0.61 vs. 0.59, 95% CI = 0.57-0.65 vs. 0.55-0.63, P = 0.010). Furthermore, the ERCC4 rs1799798 A allele was associated with lower ERCC4 mRNA expression levels according to the expression quantitative trait loci (eQTL) analysis. Our study provided some new clue in future development of biomarkers for assessing toxicity and outcomes of platinum drugs in lung cancer treatment.

Nucleotide excision repair (NER) plays a vital role in platinum-induced DNA damage during chemotherapy. We hypothesize that regulatory single nucleotide polymorphisms (rSNPs) of the core NER genes modulate clinical outcome of patients with advanced non-small cell lung cancer (NSCLC) treated with platinum-based chemotherapy (PBS). We investigated associations of 25 rSNPs in eight NER genes with progression free survival (PFS) and overall survival (OS) in 710 NSCLC patients. We found that ERCC1 rs3212924 AG/GG and XPC rs2229090 GC/CC genotypes were associated with patients’ PFS (HRadj = 1.21, 95% CI = 1.03–1.43, Padj = 0.021 for ERCC1 and HRadj = 0.80, 95% CI = 0.68–0.94, Padj = 0.007 for XPC), compared with the AA and GG genotypes, respectively. The association of XPC rs2229090 was more apparent in adenocarcinoma than in squamous cell carcinoma patients. Additionally, ERCC4 rs1799798 GA/AA genotypes were associated with poorer OS (HRadj = 1.32, 95% CI = 1.04–1.69, Padj = 0.026), compared with the GG genotype. The expression quantitative trait loci analysis revealed that ERCC1 rs3212924 and XPC rs2229090 might regulate transcription of their genes, which is consistent with their associations with survival. Larger studies are needed to validate our findings with further functional studies to elucidate the mechanisms underlying these observed associations.

Although platinum-based chemotherapy remains the standard treatment for advanced NSCLC patients, clinical outcomes are poor and most patients develop high-grade toxicities. Genetic factors, such as single nucleotide polymorphisms (SNPs) involved in platinum pharmacodynamics, metabolism and mechanism of action, may account for inter-individual differences shown in effectiveness and toxicity. Polymorphisms in genes involved in DNA repair and others such as PI3K/PTEN/AKT and TGF-β pathways have been demonstrated to be associated with response, survival and toxicity in advanced NSCLC patients treated with platinum-based chemotherapy. Other cellular processes, like DNA methylation and proliferation have been connected with clinical outcome for platinum-based chemotherapy regimens through folate metabolism and cytokine signaling. The influence of gene polymorphisms in the NER pathway on clinical outcome has been extensively investigated in advanced NSCLC patients treated with platinum-based chemotherapy but contradictory results have been reported. The most recent and thorough meta-analyses have failed to show an association between ERCC1 C118T/C8092A and ERCC5 rs1047768 polymorphisms and response to platinum based chemotherapy. However, other polymorphisms in ERCC2 (Lys751Gln and Asp312Asn) and ERCC5 (rs2094258 and rs2296147) and have been related with overall survival (OS) and progression-free survival (PFS), respectively. The Arg194Trp and Gln399Arg polymorphisms in XRCC1, have also been extensively investigated. Their effects seem to be dependent on ethnicity, and recent meta-analyses have confirmed an association with response in Asian but not in Caucasian patients. The influence on overall response rate (ORR) of the rs861539 polymorphism in XRCC3, part of (DSB) repair pathway, has also been confirmed in a meta-analysis. Finally, SNPs in genes coding proteins of the p53, PI3K, TGF-β, membrane transporters, gluthatione metabolism enzymes and cytokine pathways have been less extensively investigated. Some polymorphisms have been reported to be associated with toxicity or clinical outcome, but data generally come from a limited number of studies and need to be confirmed.

Background The nucleotide excision repair system removes a wide variety of DNA lesions from the human genome, and plays an important role in maintaining genomic stability. Single nucleotide polymorphisms (SNPs) in nucleotide excision repair are associated with the various forms of tumor susceptibility. However, the relationship between NER polymorphism and colorectal cancer is not clear. Methods In this study, three candidate SNPs including ERCC4 (rs6498486), ERCC1 (rs3212986), and ERCC5 (rs17655) were analyzed in 1101colorectal cancer patients and 1175 healthy control patients from Jiangsu province (China). Then, we performed Immunohistochemistry, qPCR, and luciferase assay to determine the potential mechanisms. Results The ERCC4 rs6498486 AC/CC genotypes show lower susceptibility to CRC than those carrying rs6498486 AA (Adjusted OR = 0.82, 95% CI = 0.69‐0.97). However, we did not observe any association between the colorectal cancer risk and the rs3212986(ERCC1) and rs17655(ERCC5) polymorphisms. Immunohistochemistry, qPCR, and luciferase assay revealed that rs6498486 A > C polymorphism in the ERCC4 promoter region could lessen the expression level of ERCC4 by impacting the binding ability of the transcription factor NF‐kB, thereby affecting the transcription activity of the ERCC4 gene and decreased ERCC4 gene expression. Conclusion In brief, our finding demonstrated that ERCC4 rs6498486 serves as a potential biomarker of CRC susceptibility for the development of colorectal cancer.

Homologous recombination deficiency conferred by alterations in BRCA1 or BRCA2 are common in breast tumors and can drive sensitivity to platinum chemotherapy and PARP inhibitors. Alterations in nucleotide excision repair (NER) activity can also impact sensitivity to DNA damaging agents, but NER activity in breast cancer has been poorly characterized. Here, we apply a novel immunofluorescence-based cellular NER assay to screen a large panel of breast epithelial and cancer cell lines. Although the majority of breast cancer models are NER proficient, we identify an example of a breast cancer cell line with profound NER deficiency. We show that NER deficiency in this model is driven by epigenetic silencing of the ERCC4 gene, leading to lack of expression of the NER nuclease XPF, and that ERCC4 methylation is also strongly correlated with ERCC4 mRNA and XPF protein expression in primary breast tumors. Re-expression of XPF in the ERCC4-deficient breast cancer rescues NER deficiency and cisplatin sensitivity, but does not impact PARP inhibitor sensitivity. These findings demonstrate the potential to use functional assays to identify novel mechanisms of DNA repair deficiency and nominate NER deficiency as a platinum sensitivity biomarker in breast cancer.

Background BRCA phenocopies are individuals with the same phenotype (i.e. cancer consistent with Hereditary Breast and Ovarian Cancer syndrome = HBOC) as their affected relatives, but not the same genotype as assessed by blood germline testing (i.e. they do not carry a germline BRCA1 or BRCA2 mutation). There is some evidence of increased risk for HBOC-related cancers in relatives of germline variant carriers even though they themselves test negative for the familial variant (BRCA non-carriers). At this time, BRCA phenocopies are recommended to undergo the same cancer surveillance as individuals in the general population. This raises the question of whether the increased cancer risk in BRCA non-carriers is due to alterations (germline, somatic or epigenetic) in other cancer-associated genes which were not analyzed during BRCA analysis. Methods To assess the nature and potential clinical significance of somatic variants in BRCA phenocopy tumors, DNA from BRCA non-carrier tumor tissue was analyzed using next generation sequencing of 572 cancer genes. Tumor diagnoses of the 11 subjects included breast, ovarian, endometrial and primary peritoneal carcinoma. Variants were called using FreeBayes genetic variant detector. Variants were annotated for effect on protein sequence, predicted function, and frequency in different populations from the 1000 genomes project, and presence in variant databases COSMIC and ClinVar using Annovar. Results None of the familial BRCA1/2 mutations were found in the tumor samples tested. The most frequently occurring somatic gene variants were ROS1(6/11 cases) and NUP98 (5/11 cases). BRCA2 somatic variants were found in 2/6 BRCA1 phenocopies, but 0/5 BRCA2 phenocopies. Variants of uncertain significance were found in other DNA repair genes (ERCC1, ERCC3, ERCC4, FANCD2, PALB2), one mismatch repair gene (PMS2), a DNA demethylation enzyme (TET2), and two histone modifiers (EZH2, SUZ12). Conclusions Although limited by a small sample size, these results support a role of selected somatic variants and epigenetic mechanisms in the development of tumors in BRCA phenocopies.

Association between the xeroderma pigmentosum complementation group F (XPF)rs2276466 located in the excision repair cross complementation group 4 (ERCC4) gene and cancer susceptibility has been widely investigated. However, results thus far have remained controversial. A meta-analysis was performed to identify the impact of this polymorphism on cancer susceptibility. PubMed, Embase and Science-Web databases were searched systematically up to May 20, 2018, to obtain all the records evaluating the association between the rs2276466 polymorphism and the risk of all types of cancers. We used the odds ratio (OR) as a measure of effect, and pooled the data in a Mantel-Haenszel weighed random-effects meta-analysis to provide a summary estimate of the impact of this polymorphism on gastrointestinal cancer, neurogenic cancer and other cancers (breast cancer and SCCHN). All the analyses were carried out in STATA 14.1.11 case–control studies that consisted of 5730 cases and 6756 controls, were eventually included in our meta-analysis. The significant association was observed between the XPFrs2276466 polymorphism and neurogenic cancer susceptibility (recessive model: OR = 1.648, 95% CI = 1.294–2.098, P

BACKGROUND Platinum-based chemoradiotherapy (CRT) is the standard treatment for locally advanced head and neck squamous-cell carcinomas (HNSCC), and most patients experience serious toxicities. The aim of this study was to investigate the association between candidate genes involved in radiation/platinum pathways and acute toxicity of CRT to determine the predictive value of these polymorphisms for toxicity. METHODS Thirty-six selected single nucleotide polymorphisms (SNPs) in 29 genes were genotyped in 110 patients treated with cisplatin-based CRT. DNA was obtained from blood samples, and SNP analysis was performed using a MassARRAY iPLEX Gold (Sequenom) method. RESULTS Patients with ERCC1 rs11615-C allele (P = .0066), ERCC1 rs735482-C allele (P = .0204), and ERCC4 rs1799801-C allele (P = .0286) had lower risk of grade 2-3 hematologic toxicity. In addition, the presence of G allele of GSTP1 was associated with a significantly lower risk of severe dysphagia (P = .0004). CONCLUSION Polymorphisms in ERCC1 and GSTP1 may act as prognostic factors of acute toxicity during treatment with CRT in HNSCC patients.