TP63-TRIM29 axis regulates enhancer methylation and chromosomal instability in prostate cancer.

BACKGROUND: Prostate adenocarcinoma (PRAD) is the second leading cause of cancer-related deaths in men. High variability in DNA methylation and a high rate of large genomic rearrangements are often observed in PRAD. RESULTS: To investigate the reasons for such high variance, we integrated DNA methylation, RNA-seq, and copy number alterations datasets from The Cancer Genome Atlas (TCGA), focusing on PRAD, and employed weighted gene co-expression network analysis (WGCNA). Our results show that only single cluster of co-expressed genes is associated with genomic and epigenomic instability. Within this cluster, TP63 and TRIM29 are key transcription regulators and are downregulated in PRAD. We discovered that TP63 regulates the level of enhancer methylation in prostate basal epithelial cells. TRIM29 forms a complex with TP63 and together regulates the expression of genes specific to the prostate basal epithelium. In addition, TRIM29 binds DNA repair proteins and prevents the formation of the TMPRSS2:ERG gene fusion typically observed in PRAD. CONCLUSION: Our study demonstrates that TRIM29 and TP63 are important regulators in maintaining the identity of the basal epithelium under physiological conditions. Furthermore, we uncover the role of TRIM29 in PRAD development.

[Intestinal microbiome as a predictor of the anti-PD-1 therapy success: metagenomic data analysis]. / Mikrobiom kishechnika kak prediktor uspekha anti-PD1 terapii: analiz metagenomnykh dannykh.

Anti-PD-1 immunotherapy has a large impact on cancer treatment but the rate of positive treatment outcomes is 40-45% and depends on many factors. One of the factors affecting the outcome of immunotherapy is the gut microbiota composition. This effect has been demonstrated both in model objects and in clinical patients groups. However, in order to identify clear causal relationships between microbiota and anti-PD1 immunotherapy response, it is necessary to expand the number of patients and experimental samples. This work presents an analysis of metagenomic data obtained using whole-genome sequencing of stool samples from melanoma patients (n=45) with different responses to anti-PD1 therapy. The analysis of the differential representation of microbial species has shown a difference in the composition of the microbiota between the experimental groups. Results of this study indicate existence of a strong link between the composition of the gut microbiota and the outcome of anti-PD1 therapy. Expansion of similar research may help develop additional predictive tools for the outcome of anti-PD1 cancer immunotherapy, as well as increase its effectiveness.

[Downregulation of OGDHL expression is associated with promoter hypermethylation in colorectal cancer].

Cell metabolic reprogramming is one of the cancer hallmarks. Glycolysis activation, along with suppression of oxidative phosphorylation and, to a lower extent, the TCA cycle, occurs in the majority of malignant tumors. A bioinformatics search for the glucose metabolism genes that are differentially expressed in colorectal cancer (CC) was performed using the data of The Cancer Genome Atlas (TCGA) Project. OGDHL for an oxoglutarate dehydrogenase complex subunit, which is involved in the TCA cycle and is indirectly responsible for the induction of apoptosis, was identified as one of the most promising candidates. A quantitative PCR analysis showed, on average, an eightfold downregulation of OGDHL in 50% (15/30) of CC samples. Based on the TCGA data, promoter hypermethylation was assumed to be a major mechanism of OGDHL inactivation. Bisulfite sequencing identified the OGDHL promoter region (+327 ... +767 relative to the transcription start site) that is often methylated in CC samples with downregulated ODGHL expression (80%, 8/10) and is possibly crucial for gene inactivation. Thus, frequent and significant OGDHL downregulation due to hypermethylation of a specific promoter region was demonstrated for CC. The OGDHL promoter methylation pattern was assumed to provide a marker for differential diagnosis of CIMP+ (CpG island methylator phenotype) tumors, which display dense hypermethylation of the promoter region in many genes.