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Background/Purpose: Bilateral diffuse uveal melanocytic proliferation is a paraneoplastic syndrome affecting the eye that is a sign of poor prognosis of underlying malignancy. This is the first documented case to show serial and sustained improvement of bilateral diffuse uveal melanocytic proliferation after immunotherapy in the setting of primary non-small-cell carcinoma of the lung. Methods: Single-center, case report. Results: A 65-year-old man reported a gradual decrease in vision and floaters in the right eye after cataract surgery. Fundus examination demonstrated diffuse multiple brown subretinal lesions bilaterally. Next-generation sequencing of melanocytic tissue of the patient described in this case revealed a specific RB1c.411A. T (p.Glu137Asp) variant with an allele frequency of 44.8%, consistent with heterozygosity. Plasma samples from the patient and a control patient with no history of cancer and/or paraneoplastic syndrome were cultured with neonatal melanocytes, which revealed a .180% increase in proliferation of normal neonatal melanocytes compared with the control. Pembrolizumab therapy was initiated, which resulted in shrinkage and stabilization of the lesions documented in serial diagnostic testing. Conclusion: In conclusion, we report a cytologically and serologically confirmed case of bilateral diffuse uveal melanocytic proliferation in a patient with a primary non-small-cell carcinoma of the lung. Next-generation sequencing of melanocytic tissue of the patient described in this case revealed a specific RB1 c.411A. T (p.Glu137Asp) variant with an allele frequency of 44.8%, consistent with heterozygosity. Furthermore, we show documented serial improvement in the patient's ocular and systemic disease with treatment. This case as one of the longest surviving confirmed cases of a patient with bilateral diffuse uveal melanocytic proliferation. [ABSTRACT FROM AUTHOR]

Aims: Compared to primary breast sarcoma (BSs), radiotherapy-induced sarcoma (RIS) is a less frequent type of secondary breast sarcoma. Undifferentiated pleomorphic sarcoma (UPS) is an even rarer occurrence within the RIS category. This study aimed to present the clinicopathologic and molecular features of breast radiotherapy-induced UPS. Methods: A retrospective study was conducted at the Third Affiliated Hospital of Soochow University to analyze three patients with radiation-induced undifferentiated pleomorphic sarcoma (UPS) following breast cancer, spanning from 2006 to 2023. The clinical and pathological variables were extracted from the medical records, while immunohistochemistry was employed to analyze the immunophenotypes of these tumors. Genomic characteristics were assessed through DNA and RNA sequencing techniques. Another 15 cases from the literature were also reviewed to better characterize the tumor. Results: The affected areas encompass the chest wall and breasts, with an incubation period ranging from 6 to 17 years. The tumor cells exhibit pleomorphism and demonstrate a high degree of pathological mitosis. Notably, two cases displayed an accelerated disease progression, characterized by recurrent tumors and metastases occurring within short intervals of 48 and 7 months respectively subsequent to the initial diagnosis. The two prevailing identified genes were TP53 (2/3, 66.7%) and RB1 (1/3, 33.3%). Through analysis of somatic copy number variation (CNV), it was discovered that two oncogenes, MCL1 (1/3, 33.3%) and MYC (1/3, 33.3%), had experienced gains in CNV. The Tumor Mutational Burden (TMB) values for case 1, case 2, and case 3 were 5.9 mut/Mb, 1.0 mut/Mb, and 3.0 mut/Mb, respectively. Moreover, the analysis of RNA-NGS (next-generation sequencing) revealed the presence of a novel gene fusion, named COL3A1-GULP1, in case 2. Conclusions: Based on our thorough analysis of research findings and previous reports, it is evident that radiotherapy-induced UPS exhibits a highly diverse and frequently severe clinical and biological behavior. Identifying tumor formation using genome sequencing can help understand its biological behavior and determine personalized treatments. [ABSTRACT FROM AUTHOR]

Background: The objective of this study was to explore the genetic etiology and propose a genetic diagnosis and counseling strategy for children with retinoblastoma (RB) and global developmental delay (GDD). Case presentation: We report on a 2 years and 4 months old boy with binocular retinoblastoma and global developmental delay (included intellectual disability, language development delay, motor development delay, etc.). Genomic DNA was extracted from peripheral blood mononuclear cells isolated from the proband and his parents. Whole exome sequencing (WES) was carried out for the proband and his parents to identify genetic etiology, which was subsequently verified by quantitative polymerase chain reaction (qPCR). The WES revealed a gross heterozygous deletion in the RB transcriptional corepressor 1 (RB1, OMIM:614041) gene, including exon 7-8, in the affected proband but not in his parents. Additionally, two pathogenic copy number variations (CNVs) were identified: a duplication at 7q11.23 and a microdeletion at 16p11.2-p12.2, respectively. Furthermore, the genomic qPCR analysis demonstrated a 50% reduction in the copy numbers of exon 7 and exon 8 in the RB1 gene of the proband, as compared to those detected in his parents. Simultaneous variants in the RB1 gene and two pathogenic CNVs can precisely explain the genetic etiology of the proband. Conclusion: The present study firstly reports a novel gross deletion variant of the RB1 gene coexisting with two pathogenic CNVs in a pediatric patient with retinoblastoma and comorbid global developmental delay in China. Additionally, our findings strongly support the use of WES in pediatric patients with RB comorbid GDD, and WES is recommended as the first-tier test. [ABSTRACT FROM AUTHOR]

Abstract Aims Compared to primary breast sarcoma (BSs), radiotherapy-induced sarcoma (RIS) is a less frequent type of secondary breast sarcoma. Undifferentiated pleomorphic sarcoma (UPS) is an even rarer occurrence within the RIS category. This study aimed to present the clinicopathologic and molecular features of breast radiotherapy-induced UPS. Methods A retrospective study was conducted at the Third Affiliated Hospital of Soochow University to analyze three patients with radiation-induced undifferentiated pleomorphic sarcoma (UPS) following breast cancer, spanning from 2006 to 2023. The clinical and pathological variables were extracted from the medical records, while immunohistochemistry was employed to analyze the immunophenotypes of these tumors. Genomic characteristics were assessed through DNA and RNA sequencing techniques. Another 15 cases from the literature were also reviewed to better characterize the tumor. Results The affected areas encompass the chest wall and breasts, with an incubation period ranging from 6 to 17 years. The tumor cells exhibit pleomorphism and demonstrate a high degree of pathological mitosis. Notably, two cases displayed an accelerated disease progression, characterized by recurrent tumors and metastases occurring within short intervals of 48 and 7 months respectively subsequent to the initial diagnosis. The two prevailing identified genes were TP53 (2/3, 66.7%) and RB1 (1/3, 33.3%). Through analysis of somatic copy number variation (CNV), it was discovered that two oncogenes, MCL1 (1/3, 33.3%) and MYC (1/3, 33.3%), had experienced gains in CNV. The Tumor Mutational Burden (TMB) values for case 1, case 2, and case 3 were 5.9 mut/Mb, 1.0 mut/Mb, and 3.0 mut/Mb, respectively. Moreover, the analysis of RNA-NGS (next-generation sequencing) revealed the presence of a novel gene fusion, named COL3A1-GULP1, in case 2. Conclusions Based on our thorough analysis of research findings and previous reports, it is evident that radiotherapy-induced UPS exhibits a highly diverse and frequently severe clinical and biological behavior. Identifying tumor formation using genome sequencing can help understand its biological behavior and determine personalized treatments.

Retinoblastoma (RB) is the most common intraocular malignant tumor in children, primarily attributed to the bi-allelic loss of the RB1 gene in the developing retina. Despite significant progress in understanding the basic pathogenesis of RB, comprehensively unravelling the intricate network of genetics and epigenetics underlying RB tumorigenesis remains a major challenge. Conventional clinical treatment options are limited, and despite the continuous identification of genetic loci associated with cancer pathogenesis, the development of targeted therapies lags behind. This review focuses on the reported genomic and epigenomic alterations in retinoblastoma, summarizing potential therapeutic targets for RB and providing insights for research into targeted therapies.

Background: Prostate cancer is a leading cause of cancer-related deaths among men, marked by heterogeneous clinical and molecular characteristics. The complexity of the molecular landscape necessitates tools for identifying multigene co-alteration patterns that are associated with aggressive disease. The identification of such gene sets will allow for deeper characterization of the processes underlying prostate cancer progression and potentially lead to novel strategies for treatment. Methods: We developed ProstaMine to systematically identify co-alterations associated with aggressiveness in prostate cancer molecular subtypes defined by high-fidelity alterations in primary prostate cancer. ProstaMine integrates genomic, transcriptomic, and clinical data from five primary and one metastatic prostate cancer cohorts to prioritize co-alterations enriched in metastatic disease and associated with disease progression. Results: Integrated analysis of primary tumors defined a set of 17 prostate cancer alterations associated with aggressive characteristics. We applied ProstaMine to NKX3-1-loss and RB1-loss tumors and identified subtype-specific co-alterations associated with metastasis and biochemical relapse in these molecular subtypes. In NKX3-1-loss prostate cancer, ProstaMine identified novel subtype-specific coalterations known to regulate prostate cancer signaling pathways including MAPK, NF-kB, p53, PI3K, and Sonic hedgehog. In RB1-loss prostate cancer, ProstaMine identified novel subtype-specific co-alterations involved in p53, STAT6, and MHC class I antigen presentation. Co-alterations impacting autophagy were noted in both molecular subtypes. Conclusion: ProstaMine is a method to systematically identify novel subtypespecific co-alterations associated with aggressive characteristics in prostate cancer. The results from ProstaMine provide insights into potential subtypespecific mechanisms of prostate cancer progression which can be formed into testable experimental hypotheses. ProstaMine is publicly available at: https:// bioinformatics.cuanschutz.edu/prostamine. [ABSTRACT FROM AUTHOR]

While loss of function (LOF) of retinoblastoma 1 (RB1) tumor suppressor is known to drive initiation of small‐cell lung cancer and retinoblastoma, RB1 mutation is rarely observed in breast cancers at their initiation. In this study, we investigated the impact on untransformed mammary epithelial cells given by RB1 LOF. Depletion of RB1 in anon‐tumorigenic MCF10A cells induced reversible growth arrest (quiescence) featured by downregulation of multiple cyclins and MYC, upregulation of p27KIP1, and lack of expression of markers which indicate cellular senescence or epithelial–mesenchymal transition (EMT). We observed a similar phenomenon in human mammary epithelial cells (HMEC) as well. Additionally, we found that RB1 depletion attenuated the activity of RAS and the downstream MAPK pathway in an RBL2/p130‐dependent manner. The expression of farnesyltransferase β, which is essential for RAS maturation, was found to be downregulated following RB1 depletion also in an RBL2/p130‐dependent manner. These findings unveiled an unexpected mechanism whereby normal mammary epithelial cells resist to tumor initiation upon RB1 LOF. [ABSTRACT FROM AUTHOR]

Aging brings about physiological dysfunction, disease, and eventual mortality. An increasing number of studies indicate that aging can easily lead to dysbiosis of the gut microbiota, which can further affect digestion, nerves, cognition, emotions, and more. Therefore, gut bacteria play an important role in regulating the physical functions of aging populations. While saponins, the primary components of American ginseng, are frequently utilized for treating common ailments in the elderly due to their potent antioxidant properties, there is a scarcity of comprehensive studies on aging organisms. This study focused on 18 month old aging mice and investigated the effects of single intervention and combined intervention of Rb1 and Re, the main components of Panax quinquefolium saponins, on the gut microbiota of aging mice. High throughput 16s RNA gene sequencing analysis was performed on the gut contents of the tested mice, and the results showed that Rb1 and Re had a significant impact on the gut microbiota. Rb1, Re, and Rb1 + Re can effectively enhance the diversity of gut microbiota, especially in the combined Rb1 + Re group, which can recover to the level of young mice. Re can promote the abundance of probiotics such as Lactobacillus, Lactobacillaceae, and Lactobacillus, and inhibit the abundance of harmful bacteria such as Enterobacteriaceae. This indicates that the intervention of Rb1, Re, and Rb1 + Re can maintain the homeostasis of gut microbiota, and the combined application of Rb1 + Re has a better effect. The relationship between aging, brain gut axis, and gut microbiota is very close. Saponins can improve the gut microbiota of aging individuals by maintaining the balance of gut microbiota and the normal function of the brain gut axis, enabling the body to achieve a gut microbiota homeostasis closer to that of young healthy mice.

Abstract Background Mantle cell lymphoma (MCL) is a chronically relapsing malignancy with deregulated cell cycle progression. We analyzed efficacy, mode of action, and predictive markers of susceptibility to palbociclib, an approved CDK 4/6 inhibitor, and its combination with venetoclax, a BCL2 inhibitor. Methods A panel of nine MCL cell lines were used for in vitro experiments. Four patient derived xenografts (PDX) obtained from patients with chemotherapy and ibrutinib-refractory MCL were used for in vivo proof-of-concept studies. Changes of the mitochondrial membrane potential, energy-metabolic pathways, AKT activity, and pro-apoptotic priming of MCL cells were evaluated by JC-1 staining, Seahorse XF analyser, genetically encoded fluorescent AKT reporter, and BH3 profiling, respectively. MCL clones with gene knockout or transgenic (over)expression of CDKN2A, MYC, CDK4, and RB1 were used to estimate impact of these aberrations on sensitivity to palbociclib, and venetoclax. Results Co-targeting MCL cells with palbociclib and venetoclax induced cytotoxic synergy in vitro and in vivo. Molecular mechanisms responsible for the observed synthetic lethality comprised palbociclib-mediated downregulation of anti-apoptotic MCL1, increased levels of proapoptotic BIM bound on both BCL2, and BCL-XL and increased pro-apoptotic priming of MCL cells mediated by BCL2-independent mechanisms, predominantly palbociclib-triggered metabolic and mitochondrial stress. Loss of RB1 resulted in palbociclib resistance, while deletion of CDKN2A or overexpression of CDK4, and MYC genes did not change sensitivity to palbociclib. Conclusions Our data strongly support investigation of the chemotherapy-free palbociclib and venetoclax combination as an innovative treatment strategy for post-ibrutinib MCL patients without RB1 deletion.

Abstract Background Combined small-cell lung carcinoma (cSCLC) represents a rare subtype of SCLC, the mechanisms governing the evolution of cancer genomes and their impact on the tumor immune microenvironment (TIME) within distinct components of cSCLC remain elusive. Methods Here, we conducted whole-exome and RNA sequencing on 32 samples from 16 cSCLC cases. Results We found striking similarities between two components of cSCLC-LCC/LCNEC (SCLC combined with large-cell carcinoma/neuroendocrine) in terms of tumor mutation burden (TMB), tumor neoantigen burden (TNB), clonality structure, chromosomal instability (CIN), and low levels of immune cell infiltration. In contrast, the two components of cSCLC-ADC/SCC (SCLC combined with adenocarcinoma/squamous-cell carcinoma) exhibited a high level of tumor heterogeneity. Our investigation revealed that cSCLC originated from a monoclonal source, with two potential transformation modes: from SCLC to SCC (mode 1) and from ADC to SCLC (mode 2). Therefore, cSCLC might represent an intermediate state, potentially evolving into another histological tumor morphology through interactions between tumor and TIME surrounding it. Intriguingly, RB1 inactivation emerged as a factor influencing TIME heterogeneity in cSCLC, possibly through neoantigen depletion. Conclusions Together, these findings delved into the clonal origin and TIME heterogeneity of different components in cSCLC, shedding new light on the evolutionary processes underlying this enigmatic subtype.

Simple Summary: Addressing RB1-deficient cancers poses substantial challenges. Dysfunctional or deleted RB1 can enhance the proliferation and spread of different cancer types. Scientists strive to grasp the intricate role of RB1 in regulating various biological processes and molecular pathways to devise innovative therapeutic strategies tailored to RB1-deficient cancers. Recent advancements have revealed encouraging tactics for combating these malignancies, heralding a path toward more precise and efficacious treatments. This review underscores the pivotal role of RB1 in cancer research and highlights its potential as a focal point for personalized therapies. The retinoblastoma (RB) transcriptional corepressor 1 (RB1) is a critical tumor suppressor gene, governing diverse cellular processes implicated in cancer biology. Dysregulation or deletion in RB1 contributes to the development and progression of various cancers, making it a prime target for therapeutic intervention. RB1′s canonical function in cell cycle control and DNA repair mechanisms underscores its significance in restraining aberrant cell growth and maintaining genomic stability. Understanding the complex interplay between RB1 and cellular pathways is beneficial to fully elucidate its tumor-suppressive role across different cancer types and for therapeutic development. As a result, investigating vulnerabilities arising from RB1 deletion-associated mechanisms offers promising avenues for targeted therapy. Recently, several findings highlighted multiple methods as a promising strategy for combating tumor growth driven by RB1 loss, offering potential clinical benefits in various cancer types. This review summarizes the multifaceted role of RB1 in cancer biology and its implications for targeted therapy. [ABSTRACT FROM AUTHOR]

Ginsenoside Rb1 is an allelopathic self-toxic substance that can affect the growth and development of ginseng. This study investigated whether the application of exogenous Rb1 enhances the pathogenicity of ginseng by regulating the antioxidant system and endogenous hormones. Rb1 can inhibit the growth and development of Panax ginseng by inducing Fusarium oxysporum under three concentrations. At the same time, the activities of four antioxidant enzymes and the contents of three endogenous hormones in the roots of Panax ginseng decreased significantly. Compared with the control group, the incidence of ginseng in different treatment groups was significantly increased and the underground growth was significantly inhibited. In conclusion, exogenous ginsenoside Rb1 with different concentrations can enhance the pathogenicity of ginseng. [ABSTRACT FROM AUTHOR]

Background: Mantle cell lymphoma (MCL) is a chronically relapsing malignancy with deregulated cell cycle progression. We analyzed efficacy, mode of action, and predictive markers of susceptibility to palbociclib, an approved CDK 4/6 inhibitor, and its combination with venetoclax, a BCL2 inhibitor. Methods: A panel of nine MCL cell lines were used for in vitro experiments. Four patient derived xenografts (PDX) obtained from patients with chemotherapy and ibrutinib-refractory MCL were used for in vivo proof-of-concept studies. Changes of the mitochondrial membrane potential, energy-metabolic pathways, AKT activity, and pro-apoptotic priming of MCL cells were evaluated by JC-1 staining, Seahorse XF analyser, genetically encoded fluorescent AKT reporter, and BH3 profiling, respectively. MCL clones with gene knockout or transgenic (over)expression of CDKN2A, MYC, CDK4, and RB1 were used to estimate impact of these aberrations on sensitivity to palbociclib, and venetoclax. Results: Co-targeting MCL cells with palbociclib and venetoclax induced cytotoxic synergy in vitro and in vivo. Molecular mechanisms responsible for the observed synthetic lethality comprised palbociclib-mediated downregulation of anti-apoptotic MCL1, increased levels of proapoptotic BIM bound on both BCL2, and BCL-XL and increased pro-apoptotic priming of MCL cells mediated by BCL2-independent mechanisms, predominantly palbociclib-triggered metabolic and mitochondrial stress. Loss of RB1 resulted in palbociclib resistance, while deletion of CDKN2A or overexpression of CDK4, and MYC genes did not change sensitivity to palbociclib. Conclusions: Our data strongly support investigation of the chemotherapy-free palbociclib and venetoclax combination as an innovative treatment strategy for post-ibrutinib MCL patients without RB1 deletion. [ABSTRACT FROM AUTHOR]

BCR-ABL tyrosine kinase inhibitors are commonly employed for the treatment of chronic myeloid leukemia, yet their impact on human malignant melanoma remains uncertain. In this study, we delved into the underlying mechanisms of specific BCR-ABL tyrosine kinase inhibitors (imatinib, nilotinib, ZM-306416, and AT-9283) in human melanoma A375P cells. We first evaluated the influence of these inhibitors on cell growth using cell proliferation and wound-healing assays. Subsequently, we scrutinized cell cycle regulation in drug-treated A375P cells using flow cytometry and Western blot assays. Notably, imatinib, nilotinib, ZM-306416, and AT-9283 significantly reduced cell proliferation and migration in A375P cells. In particular, nilotinib and AT-9283 impeded the G1/S transition of the cell cycle by down-regulating cell cycle-associated proteins, including cyclin E, cyclin A, and CDK2. Moreover, these inhibitors reduced RB phosphorylation, subsequently inhibiting E2F transcriptional activity. Consequently, the expression of the E2F target genes (CCNA2, CCNE1, POLA1, and TK-1) was markedly suppressed in nilotinib and AT9283-treated A375P cells. In summary, our findings suggest that BCR-ABL tyrosine kinase inhibitors may regulate the G1-to-S transition in human melanoma A375P cells by modulating the RB-E2F complex. [ABSTRACT FROM AUTHOR]

Introduction: Recent studies have identified that glioblastoma IDH-wildtype consists of different molecular subgroups with distinct prognoses. In order to accurately describe and classify gliomas, the Visually AcceSAble Rembrandt Images (VASARI) system was developed. The goal of this study was to evaluate the VASARI characteristics in molecular subgroups of IDH-wildtype glioblastoma. Methods: A retrospective analysis of glioblastoma IDH- wildtype with comprehensive next-generation sequencing and pre-operative and post-operative MRI was performed. VASARI characteristics and 205 genes were evaluated. Multiple comparison adjustment by the Bejamin-Hochberg false discovery rate (BH-FDR) was performed. A 1:3 propensity score match (PSM) with a Caliper of 0.2 was done. Results: 178 patients with GBM IDH-WT met the inclusion criteria. 4q12 amplified patients (n = 20) were associated with cyst presence (30% vs. 12%, p = 0.042), decreased hemorrhage (35% vs. 62%, p = 0.028), and non-restricting/mixed (35%/60%) rather than restricting diffusion pattern (5%), meanwhile, 4q12 non-amplified patients had mostly restricting (47.4%) rather than a non-restricting/mixed diffusion pattern (28.4%/23.4%). This remained statistically significant after BH-FDR adjustment (p = 0.002). PSM by 4q12 amplification showed that diffusion characteristics continued to be significantly different. Among RB1-mutant patients, 96% had well-defined enhancing margins vs. 70.6% of RB1-WT (p = 0.018), however, this was not significant after BH-FDR or PSM. Conclusions: Patients with glioblastoma IDH-wildtype harboring 4q12 amplification rarely have restricting DWI patterns compared to their wildtype counterparts, in which this DWI pattern is present in ~ 50% of patients. This suggests that some phenotypic imaging characteristics can be identified among molecular subtypes of IDH-wildtype glioblastoma. [ABSTRACT FROM AUTHOR]

Background: Combined small-cell lung carcinoma (cSCLC) represents a rare subtype of SCLC, the mechanisms governing the evolution of cancer genomes and their impact on the tumor immune microenvironment (TIME) within distinct components of cSCLC remain elusive. Methods: Here, we conducted whole-exome and RNA sequencing on 32 samples from 16 cSCLC cases. Results: We found striking similarities between two components of cSCLC-LCC/LCNEC (SCLC combined with large-cell carcinoma/neuroendocrine) in terms of tumor mutation burden (TMB), tumor neoantigen burden (TNB), clonality structure, chromosomal instability (CIN), and low levels of immune cell infiltration. In contrast, the two components of cSCLC-ADC/SCC (SCLC combined with adenocarcinoma/squamous-cell carcinoma) exhibited a high level of tumor heterogeneity. Our investigation revealed that cSCLC originated from a monoclonal source, with two potential transformation modes: from SCLC to SCC (mode 1) and from ADC to SCLC (mode 2). Therefore, cSCLC might represent an intermediate state, potentially evolving into another histological tumor morphology through interactions between tumor and TIME surrounding it. Intriguingly, RB1 inactivation emerged as a factor influencing TIME heterogeneity in cSCLC, possibly through neoantigen depletion. Conclusions: Together, these findings delved into the clonal origin and TIME heterogeneity of different components in cSCLC, shedding new light on the evolutionary processes underlying this enigmatic subtype. [ABSTRACT FROM AUTHOR]

Simple Summary: RNA polymerase (pol) III synthesizes essential and abundant non-coding RNAs, including all tRNAs. This activity can be constrained by RB, an action that may help to limit cell growth and proliferation. Previous work established that RB binds and represses TFIIIB, a factor required for pol III to transcribe any of its target genes; this explains the apparently universal effect of RB on the pol III transcriptome. We find E2F bound to chromatin in close proximity to many pol III-transcribed genes, where it may recruit RB to influence local chromatin and control the production of specific products. RB recruitment to subsets of pol III-dependent genes provides the potential for more selective regulation than the general dampening of output that can be achieved through interaction with TFIIIB. The regulatory impact of E2F may therefore be strengthened by differentially influencing levels of key non-coding RNAs such as individual tRNAs. In all cases tested, TFIIIB is responsible for recruiting pol III to its genetic templates. In mammalian cells, RB binds TFIIIB and prevents its interactions with both promoter DNA and pol III, thereby suppressing transcription. As TFIIIB is not recruited to its target genes when bound by RB, the mechanism predicts that pol III-dependent templates will not be occupied by RB; this contrasts with the situation at most genes controlled by RB, where it can be tethered by promoter-bound sequence-specific DNA-binding factors such as E2F. Contrary to this prediction, however, ChIP-seq data reveal the presence of RB in multiple cell types and the related protein p130 at many loci that rely on pol III for their expression, including RMRP, RN7SL, and a variety of tRNA genes. The sets of genes targeted varies according to cell type and growth state. In such cases, recruitment of RB and p130 can be explained by binding of E2F1, E2F4 and/or E2F5. Genes transcribed by pol III had not previously been identified as common targets of E2F family members. The data provide evidence that E2F may allow for the selective regulation of specific non-coding RNAs by RB, in addition to its influence on overall pol III output through its interaction with TFIIIB. [ABSTRACT FROM AUTHOR]

Background:Prostate cancer is a leading cause of cancer-related deaths among men, marked by heterogeneous clinical and molecular characteristics. The complexity of the molecular landscape necessitates tools for identifying multi-gene co-alteration patterns that are associated with aggressive disease. The identification of such gene sets will allow for deeper characterization of the processes underlying prostate cancer progression and potentially lead to novel strategies for treatment.Methods:We developed ProstaMine to systematically identify co-alterations associated with aggressiveness in prostate cancer molecular subtypes defined by high-fidelity alterations in primary prostate cancer. ProstaMine integrates genomic, transcriptomic, and clinical data from five primary and one metastatic prostate cancer cohorts to prioritize co-alterations enriched in metastatic disease and associated with disease progression.Results:Integrated analysis of primary tumors defined a set of 17 prostate cancer alterations associated with aggressive characteristics. We applied ProstaMine to NKX3-1-loss and RB1-loss tumors and identified subtype-specific co-alterations associated with metastasis and biochemical relapse in these molecular subtypes. In NKX3-1-loss prostate cancer, ProstaMine identified novel subtype-specific co-alterations known to regulate prostate cancer signaling pathways including MAPK, NF-kB, p53, PI3K, and Sonic hedgehog. In RB1-loss prostate cancer, ProstaMine identified novel subtype-specific co-alterations involved in p53, STAT6, and MHC class I antigen presentation. Co-alterations impacting autophagy were noted in both molecular subtypes.Conclusion:ProstaMine is a method to systematically identify novel subtype-specific co-alterations associated with aggressive characteristics in prostate cancer. The results from ProstaMine provide insights into potential subtype-specific mechanisms of prostate cancer progression which can be formed into testable experimental hypotheses. ProstaMine is publicly available at: https://bioinformatics.cuanschutz.edu/prostamine.

Abstract Multiple primary malignant neoplasms are a rare disease with tumors of different histology or morphology arising in various sites. Next-generation sequencing is essential in the etiology, diagnosis, treatment, and surveillance of this disease. No eight primary malignant neoplasm cases with high variant allele frequencies of RB1, TP53, and TERT have been reported. Herein, we report a 65-year-old male who exhibited eight primary malignancies of the vocal cord, pharynx, kidney, mouth floor, esophagus, and urinary bladder with different pathological types. The first seven tumors were early-stage tumors; the last tumor, small cell carcinoma of urinary bladder, showed liver metastasis at diagnosis. Next-generation sequencing results revealed extremely high somatic variant allele frequencies of RB1 c.1472 T > C, TP53 c.576A > G, and TERT c.-58-u66C > T (95.5%, 95.1%, and 51.0%, respectively). No germline mutations were detected. These findings denoted a heavy tumor burden and poor prognosis. This is the first report of eight primary malignant neoplasm cases with high variant allele frequencies of RB1, TP53, and TERT.

Abstract Background Retinoblastoma (RB) a tumour affecting those under 5 years, has a prevalence of 1 in 20,000, with around twenty new diagnoses per year in Sri Lanka. Unilateral and bilateral RB presents around 24 and 15 months respectively. Approximately 10% are familial. Systematic genetic testing for germline pathogenic variants of RB1, the only gene associated with an inherited risk of RB, is unavailable in Sri Lanka. Genetic testing optimizes management of affected children and at-risk siblings. This study aimed to develop accessible genetic testing to identify children with a germline pathogenic variant of RB1 in Sri Lanka. Methods Targeted next generation sequencing (NGS) for detecting pathogenic sequence variants and Gene Ratio Analysis Copy Enumeration PCR (GRACE-PCR) for detecting RB1 copy number variations (CNVs) were performed for 49 consecutive RB patients treated between 2016 and 2020 at the designated RB care unit, Lady Ridgway hospital, Colombo. Patients (bilateral RB (n = 18; 37%), unilateral n = 31) were recruited following ethical clearance and informed consent. Results There were 26 (53%) females. Mean age at diagnosis was 18 months. Thirty-five patients (71%) had undergone enucleation. Germline pathogenic variants of RB1 identified in 22/49 (45%) patients including 18 (37%; 12 bilateral and 6 unilateral) detected by targeted NGS (2 missense, 7 stop gained, 1 splice donor, 8 frameshift variants). Six were previously undescribed, likely pathogenic frameshift variants. Four bilateral RB patients had GRACE-PCR detected CNVs including one whole RB1, two intragenic deletions (exon 12/13; exon 11 and 23) and a partial duplication of exon 27. The only familial case (affected mother and child) shared the duplication. Only 2 of 4 CNVs and 10 of 18 pathogenic variants were confirmed by whole exome sequencing and Sanger sequencing respectively, due to funding limitations. Conclusions The study identified pathogenic or likely pathogenic germline RB1 sequence variants and copy number variants in 16/18 (89%) bilateral and 6/31(19%) unilateral cases, which is comparable to worldwide data (10–15% unilateral, 80–85% bilateral). Targeted NGS combined with GRACE-PCR significantly reduce the cost of RB1 testing in Sri Lanka, and may widen access for genetic diagnosis of RB patients in other low and middle income countries.

Simple Summary: Glioblastoma is the most frequent and malignant primary tumor of the brain. Patient survival is dismal and personalized therapies are missing. In the diagnostic arena, the lack of an all-inclusive molecular subgroup classification for this tumor has delayed its personalized therapy. This study presents the validation of the first molecular subgroup classification of glioblastoma in a large patient cohort, and opens the avenue to rationalized therapeutic approaches. Preliminary comparative demographic studies between Caucasian/White and African American/Black patients offer the first comparative overview of the molecular diversity of glioblastoma. One molecular subgroup, G6/Multi-RTK, assembling several targetable gene fusions, is expanded and includes novel or rare examples of such events with associated tumorigenic mechanisms and cellular phenotypes. The bioinformatic analysis of the principal oncogenic pathways reveals important genetic associations and the extent of genomic heterogeneity at the populational level, offering the first organized molecular profiling of glioblastoma to be used as a foundation for therapy design, clinical practice and scientific research. Glioblastoma is the most frequent and malignant primary neoplasm of the central nervous system. In a recent breakthrough study on a prospective Discovery cohort, I proposed the first all-inclusive molecular classification of glioblastoma into seven subgroups, G1-G7, based on MAPK pathway activation. New data from a WHO-grade-4 diffuse glioma prospective Validation cohort offers, in this study, an integrated demographic–molecular analysis of a 213-patient Combined cohort. Despite cohort differences in the median age and molecular subgroup distribution, all the prospectively-acquired cases from the Validation cohort mapped into one of the G1-G7 subgroups defined in the Discovery cohort. A younger age of onset, higher tumor mutation burden and expanded G1/EGFR-mutant and G3/NF1 glioblastoma subgroups characterized the glioblastomas from African American/Black relative to Caucasian/White patients. The three largest molecular subgroups were G1/EGFR, G3/NF1 and G7/Other. The fourth largest subgroup, G6/Multi-RTK, was detailed by describing a novel gene fusion ST7–MET, rare PTPRZ1–MET, LMNA–NTRK1 and GOPC–ROS1 fusions and their overexpression mechanisms in glioblastoma. The correlations between the MAPK pathway G1-G7 subgroups and the PI3-kinase/PTEN, TERT, cell cycle G1 phase and p53 pathways defined characteristic subgroup pathway profiles amenable to personalized targeted therapy. This analysis validated the first all-inclusive molecular classification of glioblastoma, showed significant demographic and molecular differences between subgroups, and provided the first ethnic molecular comparison of glioblastoma. [ABSTRACT FROM AUTHOR]

Intraductal carcinoma of the prostate (IDC‐P) is an aggressive subtype of prostate cancer characterized by the growth of tumor cells within the prostate ducts. It is often found alongside invasive carcinoma and is associated with poor prognosis. Understanding the molecular mechanisms driving IDC‐P is crucial for improved diagnosis, prognosis, and treatment strategies. This review summarizes the molecular characteristics of IDC‐P and their prognostic indications, comparing them to conventional prostate acinar adenocarcinoma, to gain insights into its unique behavior and identify potential therapeutic targets. [ABSTRACT FROM AUTHOR]

Retinoblastoma (RB) is a malignant ocular cancer that affects children. Several microRNAs (miRNAs) have been implicated in RB regulation. The present study aimed to investigate the role of miR-4529-3p in RB pathogenesis. Scratch, Transwell, and Cell Counting Kit (CCK)-8 assays were conducted to assess the migratory, invasive, and proliferative abilities of RB cells. The expression levels of miR-4529-3p, RB1, and ERK pathway-related proteins were analyzed using western blotting and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). Target relationships were verified using dual-luciferase reporter experiments. A murine RB model was developed to analyze the effects of miR-4529-3p on RB tumor growth in vivo. Our experiments revealed high levels of miR-4529-3p and low levels of RB1 in RB tissues. Functional analyses revealed that the migratory, invasive, and proliferative abilities of RB cells were repressed by miR-4529-3p inhibition. Similarly, p-ERK 1/2 protein levels were suppressed by miR-4529-3p inhibition. Furthermore, downregulation of miR-4529-3p limited tumor growth in vivo. Mechanistically, miR-4259-3p targets RB1. Interestingly, RB1 silencing abrogated the alleviative effects of miR-4529-3p downregulation in RB cells. MiR-4529-3p promotes RB progression by inhibiting RB1 and activating the ERK pathway. This evidence suggests that the miR-4529-3p/RB1 regulatory axis may be a prospective target for RB treatment in clinical settings. [ABSTRACT FROM AUTHOR]

Background: Onychomatricoma is a nail neoplasm that usually presents as longitudinal nail plate thickening, involving either the partial or whole nail. Histopathologically, it is characterized by deep invaginations of the proliferating nail matrix and proliferation of CD34+ and CD10+ spindle cells with collagenous to myxoid stroma. Onychomatricoma has been considered a fibroepithelial neoplasm. Recently, RB1 loss has been verified using array comparative genomic hybridization. Methods: This study investigated the RB1 status in onychomatricoma with morphological methods. Results: Six patients with onychomatricoma were included in the study. RB1 status was assessed using immunohistochemical staining and fluorescence in situ hybridization. Immunohistochemical staining showed that all six cases experienced RB1 loss in the mesenchymal component of onychomatricoma but not in the proliferated nail matrix. Fluorescence in situ hybridization in five cases showed a monoallelic deletion of the RB1 locus in the mesenchymal component but not in the proliferated nail matrix. Conclusions: RB1 loss was observed only in the mesenchymal component of onychomatricoma. Our findings suggest that the proliferated nail matrix in onychomatricoma represents reactive hyperplasia of various degrees secondary to neoplastic mesenchymal proliferation. This indicates that onychomatricoma should be recognized as an RB1‐deleted soft tissue neoplasm rather than a fibroepithelial neoplasm. [ABSTRACT FROM AUTHOR]

Simple Summary: Histologic transformation has been increasingly common in clinical. However, whether the transformed tumor to be a new component or a combined tumor remains controversial. This study aimed to explore the relationship and focused on 21 combined neuroendocrine carcinoma. The frequency of p53 inactivation as assessed by immunohistochemistry in NEC and non-NEC components was 76.2 and 76.2%, and for Rb, it was 66.7 and 61.9%, respectively. For molecular alterations assessed by whole exome sequencing, the frequency of mutations in TP53, RB1, and EGFR in NEC and non-NEC components was 81.0/81.0%, 28.6/28.6%, and 42.9/42.9%, respectively. Immunohistochemistry was relatively more sensitive in Rb detection. The different components were found to have a common clonal origin based on the clonal evolution analysis of all 21 cases, which was consistent with previous studies on "HT". Our findings highlight the significance of evaluating the protein expression and gene status of TP53, RB1, and EGFR to discover the potential combined component or recognize the potential transformation cases. Therefore, our findings have strong implications in the clinical assessment of combined tumors. Histologic transformation (HT) is common following targeted therapy in adenocarcinoma. However, whether the transformed tumor is a new component or a combined neuroendocrine carcinoma (C-NEC) remains controversial. We aimed to explore the relationship between pulmonary C-NEC and HT. Macro-dissection was performed on different components of surgically resected C-NEC samples. Molecular alterations and clonal evolution were analyzed using whole exome sequencing (WES). The gene statuses for TP53 and RB1 were determined using immunohistochemistry (IHC) and WES to analyze the relationship between C-NEC and reported HT. Sixteen combined small-cell lung cancer patients and five combined large-cell neuroendocrine carcinoma patients were enrolled. The frequency of p53 and Rb inactivation, assessed using IHC in NEC and non-NEC components, was 76.2/76.2% and 66.7/61.9%, respectively. The expression consistency between the components was 81.0 and 85.7% for p53 and Rb, respectively. The frequencies of TP53, RB1, and EGFR mutations, assessed using WES in NEC and non-NEC components, were 81.0/81.0%, 28.6/28.6%, and 42.9/42.9%, respectively. The concordance rates for TP53, RB1, and EGFR were 90.5, 71.4, and 90.5%, respectively. The consistency rate between IHC and WES was 81.0 and 61.9% for TP53 and RB1, respectively. The different components had a common clonal origin for the 21 C-NECs in the clonal analysis, consistent with previous studies on HT. Our study shows that IHC is more sensitive for Rb detection and C-NEC, and the reported HT may be due to differences in evaluations between pathologist and clinicians. Assessing the p53/Rb and EGFR status for such cases would help in recognizing potential transformation cases or uncovering potential combined components. [ABSTRACT FROM AUTHOR]

Different authors have recently described a subtype of lipoma characterized by variation of adipocyte size, single cell fat necrosis, and a subset with minimal to mild nuclear atypia, and termed these as anisometric cell/dysplastic lipoma (AC/DL). These lipomas follow a benign course and rarely recur. In 3 examples, AC/DL has occurred in patients with childhood retinoblastoma (RB). We report another such example where multiple AC/DL occurred in the neck and back of a 30-year-old male who had germline RB1 gene deletion and bilateral RB in infancy. On excision, all tumors histologically showed similar morphology of adipocyte anisometry, focal single cell necrosis with surrounding binucleated or multinucleated histiocytes, hyperchromatic and minimally atypical lipocyte nuclei, vacuolated Lockhern change, rare foci of fibromyxoid change, occasional mononuclear cell clusters around capillaries, and loss of RB1 immunostaining. Unequivocal atypical cells, lipoblasts, floret-nucleated or multinucleated giant cells were absent. Molecular analysis of tumor cells showed monoallelic RB1 gene loss without amplification of MDM2 and CDK4 genes. Short-term follow up did not show tumor recurrence. AC/DLs in RB survivors are characterized by multiplicity, unifying histology, and benign course. Their biology appears distinct from ordinary lipomas, spindle cell lipomas, and atypical lipomatous tumors. [ABSTRACT FROM AUTHOR]

Background: Retinoblastoma (RB) a tumour affecting those under 5 years, has a prevalence of 1 in 20,000, with around twenty new diagnoses per year in Sri Lanka. Unilateral and bilateral RB presents around 24 and 15 months respectively. Approximately 10% are familial. Systematic genetic testing for germline pathogenic variants of RB1, the only gene associated with an inherited risk of RB, is unavailable in Sri Lanka. Genetic testing optimizes management of affected children and at-risk siblings. This study aimed to develop accessible genetic testing to identify children with a germline pathogenic variant of RB1 in Sri Lanka. Methods: Targeted next generation sequencing (NGS) for detecting pathogenic sequence variants and Gene Ratio Analysis Copy Enumeration PCR (GRACE-PCR) for detecting RB1 copy number variations (CNVs) were performed for 49 consecutive RB patients treated between 2016 and 2020 at the designated RB care unit, Lady Ridgway hospital, Colombo. Patients (bilateral RB (n = 18; 37%), unilateral n = 31) were recruited following ethical clearance and informed consent. Results: There were 26 (53%) females. Mean age at diagnosis was 18 months. Thirty-five patients (71%) had undergone enucleation. Germline pathogenic variants of RB1 identified in 22/49 (45%) patients including 18 (37%; 12 bilateral and 6 unilateral) detected by targeted NGS (2 missense, 7 stop gained, 1 splice donor, 8 frameshift variants). Six were previously undescribed, likely pathogenic frameshift variants. Four bilateral RB patients had GRACE-PCR detected CNVs including one whole RB1, two intragenic deletions (exon 12/13; exon 11 and 23) and a partial duplication of exon 27. The only familial case (affected mother and child) shared the duplication. Only 2 of 4 CNVs and 10 of 18 pathogenic variants were confirmed by whole exome sequencing and Sanger sequencing respectively, due to funding limitations. Conclusions: The study identified pathogenic or likely pathogenic germline RB1 sequence variants and copy number variants in 16/18 (89%) bilateral and 6/31(19%) unilateral cases, which is comparable to worldwide data (10–15% unilateral, 80–85% bilateral). Targeted NGS combined with GRACE-PCR significantly reduce the cost of RB1 testing in Sri Lanka, and may widen access for genetic diagnosis of RB patients in other low and middle income countries. [ABSTRACT FROM AUTHOR]

Aging is a major risk factor for the development of many pathological processes, such as reduced immunity, cancer, cardiovascular diseases or neurodegenerative diseases, while age-related chronic diseases are the most common causes of death. This paper studies the effects of American ginseng saponin Rb1 and Re alone and combined intervention on the immune system of aging mouse models, by using 30 mg/kg Rb1, 15 mg/kg Re, and Rb1 + Re (30 mg/kg Rb1 and 15 mg/kg Re (co-intervention) was used to intervene in the aging model, and immune indicators such as thymus index, spleen index, interleukin and interferon were detected to evaluate the impact of Rb1 and Re on immune function. The results show that Rb1 and Re intervention alone can increase the spleen index by 7%–12% and the thymus index by 12%–19% in the aging model. After Rb1 or Re alone intervened, the apoptotic cells in the thymus were slightly reduced, and the proportion of apoptotic cells was reduced. The combination of Rb1 + Re can promote the thymus index and spleen index to increase by 23.40% and 25.5% respectively, which is more advantageous than Rb1 or Re alone. In addition, Rb1 and Re intervention can reduce the level of interferon INF to a level comparable to that of young mice. Rb1 + Re can not only reduce the INF content, but also reduce the TNF content. The above results show that American ginseng saponin Rb1 and Re can delay the decline of the immune system in the aging model, and the combined intervention of the two is significantly better than individual intervention in the recovery of the immune system. This paper can provide theoretical basis and data support for the development of American ginseng nutritional supplements and its application in aging groups products to improve immunity.

Abstract This review presents current knowledge on the molecular biology of retinoblastoma (RB). Retinoblastoma is an intraocular tumor with hereditary and sporadic forms. 8,000 new cases of this ocular malignancy of the developing retina are diagnosed each year worldwide. The major gene responsible for retinoblastoma is RB1, and it harbors a large spectrum of pathogenic variants. Tumorigenesis begins with mutations that cause RB1 biallelic inactivation preventing the production of functional pRB proteins. Depending on the type of mutation the penetrance of RB is different. However, in small percent of tumors additional genes may be required, such as MYCN, BCOR and CREBBP. Additionally, epigenetic changes contribute to the progression of retinoblastoma as well. Besides its role in the cell cycle, pRB plays many additional roles, it regulates the nucleosome structure, participates in apoptosis, DNA replication, cellular senescence, differentiation, DNA repair and angiogenesis. Notably, pRB has an important role as a modulator of chromatin remodeling. In recent years high-throughput techniques are becoming essential for credible biomarker identification and patient management improvement. In spite of remarkable advances in retinoblastoma therapy, primarily in high-income countries, our understanding of retinoblastoma and its specific genetics still needs further clarification in order to predict the course of this disease and improve therapy. One such approach is the tumor free DNA that can be obtained from the anterior segment of the eye and be useful in diagnostics and prognostics.

Multiple primary malignant neoplasms are a rare disease with tumors of different histology or morphology arising in various sites. Next-generation sequencing is essential in the etiology, diagnosis, treatment, and surveillance of this disease. No eight primary malignant neoplasm cases with high variant allele frequencies of RB1, TP53, and TERT have been reported. Herein, we report a 65-year-old male who exhibited eight primary malignancies of the vocal cord, pharynx, kidney, mouth floor, esophagus, and urinary bladder with different pathological types. The first seven tumors were early-stage tumors; the last tumor, small cell carcinoma of urinary bladder, showed liver metastasis at diagnosis. Next-generation sequencing results revealed extremely high somatic variant allele frequencies of RB1 c.1472 T > C, TP53 c.576A > G, and TERT c.-58-u66C > T (95.5%, 95.1%, and 51.0%, respectively). No germline mutations were detected. These findings denoted a heavy tumor burden and poor prognosis. This is the first report of eight primary malignant neoplasm cases with high variant allele frequencies of RB1, TP53, and TERT. [ABSTRACT FROM AUTHOR]

Abstract Primary breast neuroendocrine (NE) neoplasms are uncommon, and definitions harbor controversy. We retrospectively collected 73 triple‐negative breast cancers (TNBC) and evaluated NE biomarker expression along with p53 aberrant staining (which correlates with TP53 gene mutation) and Rb protein loss by immunohistochemistry. In the study cohort, we found 11 (15%) cases of TNBC with neuroendocrine differentiation (TNBC‐NED) showing positivity for one or more NE markers (synaptophysin/chromogranin/insulinoma‐associated protein 1 [INSM1]). We also identified one separate small cell neuroendocrine carcinoma. Histologic types for these 11 TNBC‐NED cases were as follows: 8 invasive ductal carcinoma (IDC) not otherwise specified (NOS), 2 IDC with apocrine features, 1 IDC with solid papillary features. INSM1 had the highest positivity and was seen in all 11 carcinomas. Seven (64%) cases showed p53 aberrant staining, 6 (55%) had Rb protein loss, while 6 (55%) had p53/Rb co‐aberrant staining/protein loss. TNBC‐NED was associated with Rb protein loss (p

Background: Ginseng has been used as a traditional medicine for treatment of many diseases and for general health maintenance. Previously, we showed that ginseng did not demonstrate estrogenic property in ovariectomized mouse model. However, it is still possible that disruption of steroidogenesis leading to indirect hormonal activity. Methods: The hormonal activities were examined in compliance with OECD guidelines for detecting endocrine disrupting chemicals: test guideline (TG) No. 456 (an in vitro assay method for detecting steroidogenesis property) and TG No. 440 (an in vivo short-term screening method for chemicals with uterotrophic property). Results: Korean Red Ginseng (KRG) and ginsenosides Rb1, Rg1, and Rg3 did not interfere with estrogen and testosterone hormone synthesis as examined in H295 cells according to TG 456. KRG treatment to ovariectomized mice did not show a significant change in uterine weight. In addition, serum estrogen and testosterone levels were not change by KRG intake. Conclusion: These results clearly demonstrate that there is no steroidogenic activity associated with KRG and no disruption of the hypothalamic-pituitary-gonadal axis by KRG. Additional tests will be performed in pursuit of cellular molecular targets of ginseng to manifest mode of action.

IntroductionSmall cell lung cancer (SCLC) transformation serves as a significant mechanism of resistance to tyrosine kinase inhibitors (TKIs) in advanced non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations. To address this clinical challenge, we conducted a retrospective analysis at Zhejiang University School of Medicine, the First Affiliated Hospital, focusing on patients with EGFR sensitizing mutations.MethodsA total of 1012 cases were included in this retrospective analysis. The cohort primarily consisted of patients with EGFR sensitizing mutations. Biopsy-confirmed small cell transformation was observed in seven patients, accounting for 0.7% of the cases. All patients in this subset were initially diagnosed with stage IV adenocarcinoma (ADC), with four cases classified as poorly differentiated and three as moderately to poorly differentiated ADC. EGFR exon 19 deletions were identified in five of these cases. Next-generation sequencing (NGS) was performed on seven cases, revealing mutations in the tumor protein p53 (TP53) gene in four cases and loss of the retinoblastoma1 (RB1) gene in three cases.ResultsThe median duration from the initial diagnosis to small cell transformation was 35.9 months (interquartile range: 12.1–84 months). Following small cell transformation during EGFR inhibition, all patients received etoposide/platinum-based treatment, leading to a median progression-free survival (PFS) of 4.7 months (interquartile range: 2.7–10.1 months). Notably, most patients in this series had poorly differentiated adenocarcinomas at the outset. TP53 mutations and RB1 loss were common genetic alterations observed in patients with small cell transformation in this cohort.DiscussionThe findings underscore the clinical significance of SCLC transformation as a resistance mechanism to EGFR TKIs in NSCLC with EGFR mutations. The observed genetic alterations, including TP53 mutations and RB1 loss, suggest potential associations with the transformation process and warrant further investigation. Understanding the genetic landscape and clinical outcomes in patients experiencing small cell transformation can contribute to improved strategies for managing resistance in EGFR-mutant NSCLC.

This review presents current knowledge on the molecular biology of retinoblastoma (RB). Retinoblastoma is an intraocular tumor with hereditary and sporadic forms. 8,000 new cases of this ocular malignancy of the developing retina are diagnosed each year worldwide. The major gene responsible for retinoblastoma is RB1, and it harbors a large spectrum of pathogenic variants. Tumorigenesis begins with mutations that cause RB1 biallelic inactivation preventing the production of functional pRB proteins. Depending on the type of mutation the penetrance of RB is different. However, in small percent of tumors additional genes may be required, such as MYCN, BCOR and CREBBP. Additionally, epigenetic changes contribute to the progression of retinoblastoma as well. Besides its role in the cell cycle, pRB plays many additional roles, it regulates the nucleosome structure, participates in apoptosis, DNA replication, cellular senescence, differentiation, DNA repair and angiogenesis. Notably, pRB has an important role as a modulator of chromatin remodeling. In recent years high-throughput techniques are becoming essential for credible biomarker identification and patient management improvement. In spite of remarkable advances in retinoblastoma therapy, primarily in high-income countries, our understanding of retinoblastoma and its specific genetics still needs further clarification in order to predict the course of this disease and improve therapy. One such approach is the tumor free DNA that can be obtained from the anterior segment of the eye and be useful in diagnostics and prognostics. [ABSTRACT FROM AUTHOR]

Retinoblastoma is a common primary intraocular malignant tumor that affects infants and young children. Radiation therapy for hereditary retinoblastoma increases the risk of secondary malignancy. The present report discusses the case of a retinoblastoma survivor who developed secondary leiomyosarcoma 42 years after receiving radiation therapy. The retinoblastoma of the patient was unilateral, and the patient had no family history of the disease. RNA and DNA panel sequencing of the leiomyosarcoma tissue was performed to elucidate the molecular mechanism of this secondary malignancy. The RNA panel sequencing detected a germline reciprocal translocation of RB1 and DMXL1, leading to a diagnosis of possible hereditary retinoblastoma. Furthermore, it detected a somatic fusion gene (RAD51-KNL1). The DNA panel sequencing identified various germline or somatic variants, including a somatic splice acceptor site mutation of TP53. We hypothesized that the molecular mechanism of the secondary malignancy of this patient was the combination of a germline reciprocal translocation of RB1 and DMXL1 and the accumulation of various somatic mutations containing the splice acceptor site mutation of TP53, which ultimately led to the development of a secondary leiomyosarcoma. Further prospective investigations are necessary to fully understand the role of reciprocal translocation of RB1 and DMXL1 or other mutations in the tumorigenesis of second malignancies in patients with hereditary retinoblastoma. [ABSTRACT FROM AUTHOR]

Background: Demyelination has been observed in neurological disorders, motivating researchers to search for components for enhancing remyelination. Previously we found that Rb1, a major ginsenoside in Korean Red Ginseng (KRG), enhances myelin formation. However, it has not been studied whether Rb1 or KRG function in remyelination after demyelination in vivo. Methods: Mice were fed 0.2% cuprizone-containing chow for 5 weeks and returned to normal chow with daily oral injection of vehicle, KRG, or Rb1 for 3 weeks. Brain sections were stained with luxol fast blue (LFB) staining or immunohistochemistry. Primary oligodendrocyte or astrocyte cultures were subject to normal or stress condition with KRG or Rb1 treatment to measure gene expressions of myelin, endoplasmic reticulum (ER) stress, antioxidants and leukemia inhibitory factor (LIF). Results: Compared to the vehicle, KRG or Rb1 increased myelin levels at week 6.5 but not 8, when measured by the LFB+ or GST-pi+ area within the corpus callosum. The levels of oligodendrocyte precursor cells, astrocytes, and microglia were high at week 5, and reduced afterwards but not changed by KRG or Rb1. In primary oligodendrocyte cultures, KRG or Rb1 increased expression of myelin genes, ER stress markers, and antioxidants. Interestingly, under cuprizone treatment, elevated ER stress markers were counteracted by KRG or Rb1. Under rotenone treatment, reduced myelin gene expressions were recovered by Rb1. In primary astrocyte cultures, KRG or Rb1 decreased LIF expression. Conclusion: KRG and Rb1 may improve myelin regeneration during the remyelination phase in vivo, potentially by directly promoting myelin gene expression.

BCR-ABL tyrosine kinase inhibitors are commonly employed for the treatment of chronic myeloid leukemia, yet their impact on human malignant melanoma remains uncertain. In this study, we delved into the underlying mechanisms of specific BCR-ABL tyrosine kinase inhibitors (imatinib, nilotinib, ZM-306416, and AT-9283) in human melanoma A375P cells. We first evaluated the influence of these inhibitors on cell growth using cell proliferation and wound-healing assays. Subsequently, we scrutinized cell cycle regulation in drug-treated A375P cells using flow cytometry and Western blot assays. Notably, imatinib, nilotinib, ZM-306416, and AT-9283 significantly reduced cell proliferation and migration in A375P cells. In particular, nilotinib and AT-9283 impeded the G1/S transition of the cell cycle by down-regulating cell cycle-associated proteins, including cyclin E, cyclin A, and CDK2. Moreover, these inhibitors reduced RB phosphorylation, subsequently inhibiting E2F transcriptional activity. Consequently, the expression of the E2F target genes (CCNA2, CCNE1, POLA1, and TK-1) was markedly suppressed in nilotinib and AT9283-treated A375P cells. In summary, our findings suggest that BCR-ABL tyrosine kinase inhibitors may regulate the G1-to-S transition in human melanoma A375P cells by modulating the RB-E2F complex.

Introduction: Immune checkpoint inhibitors (ICI) have changed the treatment of non-small cell lung cancer (NSCLC). Furthermore, compared with monotherapy, ICI combination therapy had better efficacy and partly different mechanism. Therefore, we aim to investigate and improve biomarkers specialized for ICI combination therapy. Methods: We enrolled 53 NSCLC patients treated with ICI combination therapy and collected their tissue and plasma samples to perform next-generation sequencing (NGS) with a 425-gene panel. Results: The line of treatment was the only clinical factor significantly affecting objective response rate (ORR) and progression-free survival (PFS). Surprisingly, classical markers PD-L1 and TMB only had limited predictive values in the ICI combination therapy. Instead, we found RB1 mutation was significantly associated with prognosis. Patients with mutated RB1 had shorter PFS than those with wild RB1 (134d vs 219d, p=0.018). Subsequent analysis showed the RB1 related mutated cell cycle and chromosomal instability were also deleterious to prognosis (103d vs 411d, p<0.001; 138d vs 505d, p=0.018). Additionally, patients with more circulating tumor DNA (ctDNA) had significantly shorter PFS (41d vs 194d, p=0.0043). Conclusion: This study identified that NSCLC patients with mutated RB1 were less sensitive to ICI combination therapy. RB1 mutations and following cell cycle abnormalities and chromosomal instability can potentially guide clinical management. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS) is the most prevalent type of bone tumor, but slow progress has been achieved in disentangling the full set of genomic events involved in its initiation and progression. We assessed by NGS the mutational spectrum of 28 primary OSs from Brazilian patients, and identified 445 potentially deleterious SNVs/indels and 1176 copy number alterations (CNAs). TP53 was the most recurrently mutated gene, with an overall rate of ~60%, considering SNVs/indels and CNAs. The most frequent CNAs (~60%) were gains at 1q21.2q21.3, 6p21.1, and 8q13.3q24.22, and losses at 10q26 and 13q14.3q21.1. Seven cases presented CNA patterns reminiscent of complex events (chromothripsis and chromoanasynthesis). Putative RB1 and TP53 germline variants were found in five samples associated with metastasis at diagnosis along with complex genomic patterns of CNAs. PTPRQ, KNL1, ZFHX4, and DMD alterations were prevalent in metastatic or deceased patients, being potentially indicative of poor prognosis. TNFRSF11B, involved in skeletal system development and maintenance, emerged as a candidate for osteosarcomagenesis due to its biological function and a high frequency of copy number gains. A protein–protein network enrichment highlighted biological pathways involved in immunity and bone development. Our findings reinforced the high genomic OS instability and heterogeneity, and led to the identification of novel disrupted genes deserving further evaluation as biomarkers due to their association with poor outcomes. [ABSTRACT FROM AUTHOR]

Aim: Impaired apoptosis and proliferation resulted in autoreactive lymphocyte development and inflammation in Rheumatoid arthritis (RA). TP53, BAX, FOXO1, and RB1 are related genes in cell survival, proliferation, and inflammation which could be important in RA development and disease severity. Here we investigated their expression in peripheral blood mononuclear cells (PBMCs) from RA patients in comparison to healthy controls. Methods: Fifty healthy controls and 50 RA patients were selected. The quantitative real‐time polymerase chain reaction was used to assess the gene expression level in PBMCs. Results: The mRNA expression of TP53 (FC = 0.65, p =.000), BAX (FC = 0.76, p =.008), FOXO1 (FC = 0.59, p =.000) and RB1 (FC = 0.50, p =.000) were significantly reduced in RA PBMCs. TP53 expression was negatively correlated with miR‐16‐5p (p =.032) and FOXO1 expression was negatively correlated with miR‐335‐5p (p =.005) and miR‐34a‐5p (p =.014). A positive correlation was seen between TP53 expression and its downstream gene, BAX (p =.001). FOXO1 expression was also negatively correlated with disease activity, DAS28 (p =.021). Conclusion: All selected genes have downregulated expression in RA PBMCs which could be correlated with RA pathogenesis by regulating apoptosis, cell survival, inflammatory mediator production, and proliferation. Due to the correlation of miR‐16‐5p, miR‐34a‐5p, and miR‐335‐5p with TP53 and FOXO1 expression in RA PBMCs, they could be used as future therapeutic targets. [ABSTRACT FROM AUTHOR]

Primary breast neuroendocrine (NE) neoplasms are uncommon, and definitions harbor controversy. We retrospectively collected 73 triple‐negative breast cancers (TNBC) and evaluated NE biomarker expression along with p53 aberrant staining (which correlates with TP53 gene mutation) and Rb protein loss by immunohistochemistry. In the study cohort, we found 11 (15%) cases of TNBC with neuroendocrine differentiation (TNBC‐NED) showing positivity for one or more NE markers (synaptophysin/chromogranin/insulinoma‐associated protein 1 [INSM1]). We also identified one separate small cell neuroendocrine carcinoma. Histologic types for these 11 TNBC‐NED cases were as follows: 8 invasive ductal carcinoma (IDC) not otherwise specified (NOS), 2 IDC with apocrine features, 1 IDC with solid papillary features. INSM1 had the highest positivity and was seen in all 11 carcinomas. Seven (64%) cases showed p53 aberrant staining, 6 (55%) had Rb protein loss, while 6 (55%) had p53/Rb co‐aberrant staining/protein loss. TNBC‐NED was associated with Rb protein loss (p < 0.001), as well as p53/Rb co‐aberrant staining/protein loss (p < 0.001). In 61 cases negative for NE markers, 37 (61%) showed p53 aberrant staining, while 5 (8%) had Rb protein loss. We also analyzed genomic and transcriptomic data from The Cancer Genome Atlas (TCGA) PanCancer Atlas of 171 basal/TNBC patients. Transcriptomic analysis revealed mRNA expression of RB1 to be correlated negatively with SYN1 mRNA expression (p = 0.0400) and INSM1 mRNA expression (p = 0.0106) in this cohort. We would like to highlight the importance of these findings. TNBC‐NED is currently diagnosed as TNBC, and although it overlaps morphologically with TNBC without NED, the unique p53/Rb signature highlights a genetic overlap with NE carcinomas of the breast. [ABSTRACT FROM AUTHOR]

The general notion of complete hydatidiform moles is that most of them consist entirely of paternal DNA; hence, they do not express p57, a paternally imprinted gene. This forms the basis for the diagnosis of hydatidiform moles. There are about 38 paternally imprinted genes. The aim of this study is to determine whether other paternally imprinted genes could also assist in the diagnostic approach of hydatidiform moles. This study comprised of 29 complete moles, 15 partial moles and 17 non-molar abortuses. Immunohistochemical study using the antibodies of paternal-imprinted (RB1, TSSC3 and DOG1) and maternal-imprinted (DNMT1 and GATA3) genes were performed. The antibodies' immunoreactivity was evaluated on various placental cell types, namely cytotrophoblasts, syncytiotrophoblasts, villous stromal cells, extravillous intermediate trophoblasts and decidual cells. TSSC3 and RB1 expression were observed in all cases of partial moles and non-molar abortuses. In contrast, their expression in complete moles was identified in 31% (TSSC3) and 10.3% (RB1), respectively (p < 0.0001). DOG1 was consistently negative in all cell types in all cases. The expressions of maternally imprinted genes were seen in all cases, except for one case of complete mole where GATA3 was negative. Both TSSC3 and RB1 could serve as a useful adjunct to p57 for the discrimination of complete moles from partial moles and non-molar abortuses, especially in laboratories that lack comprehensive molecular service and in cases where p57 staining is equivocal. [ABSTRACT FROM AUTHOR]

Spindle cell lipoma (SCL) is a benign adipocytic tumor that primarily occurs in the subcutis of the posterior neck, upper back, and shoulder, particularly of middle-aged males. SCL and pleomorphic lipoma (PL) represent a morphological spectrum of one disease process. The lesion typically presents as a relatively small (<5 cm), mobile, slow-growing, painless mass. Magnetic resonance imaging reveals the lesion to be a welldefined subcutaneous mass with a mixture of adipose and nonadipose components. Intense enhancement of the non-adipose component is seen after contrast administration. Histologically, SCL is composed of variable distributions of mature adipocytes, bland spindle cells and ropey collagen bundles and PL also contains pleomorphic and multinucleated floret-like giant cells. By immunohistochemistry, the spindle and pleomorphic/floretlike giant cells of SCL/PL are diffusely positive for CD34 and show loss of nuclear RB transcriptional corepressor 1 (RB1) expression. Recent cytogenetic and molecular genetic studies have shown heterozygous deletions of 13q14, including the RB1 gene. SCL/PL can be successfully treated with simple excision, with a very low recurrence rate. Knowledge of these peculiar tumors is important because it can mimic a variety of benign and malignant soft-tissue tumors. This review provides an updated overview of the clinical, radiological, histopathological, cytogenetic, and molecular genetic features of SCL/PL. [ABSTRACT FROM AUTHOR]

Mutations that result in the loss of function of pRB were first identified in retinoblastoma and since then have been associated with the propagation of various forms of cancer. pRB is best known for its key role as a transcriptional regulator during cell cycle exit. Beyond the ability of pRB to regulate transcription of cell cycle progression genes, pRB can remodel chromatin to exert several of its other biological roles. In this review, we discuss the diverse functions of pRB in epigenetic regulation including nucleosome mobilization, histone modifications, DNA methylation and non-coding RNAs.

Treatment of advanced non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutation with EGFR-tyrosine kinase inhibitors (EGFR-TKIs) can achieve good disease control, but it will inevitably produce drug resistance. About 3%-10% of the resistance mechanism is small cell transformation. Two cases of stage IV lung adenocarcinoma with EGFR mutation were reported and the disease was controlled after EGFR-TKIs treatment. In case 1, progression-free survival (PFS) before small cell carcinoma transformation was 16 months, and in case 2, PFS before small cell carcinoma transformation was 24 months. Subsequent biopsy after disease progression indicated a shift to small cell lung cancer. Case 1 PFS after small cell carcinoma transformation was 6 months, and case 2 PFS after small cell carcinoma transformation was 8 months, and overall survival (OS) was 36 months, which significantly prolonged the patient's survival. At the same time, the literature of such drug resistance mutations was reviewed. For patients with advanced NSCLC with sensitive mutations, it is necessary to conduct secondary histopathological tests after TKIs treatment resistance, and select subsequent treatment according to different resistance mechanisms for the whole course of disease management.