Project description:To investigate the DNA methylation landscape differences between CAFs and NFs in colorectal cancer, we extracted primary fibroblasts from colorectal cancer tissue and para-cancerous tissue for 850K chip analysis.
Project description:DNA methylation is an epigenetic mark that is altered in cancer and aging tissues. The effects of extrinsic factors on DNA methylation remain incompletely understood. Microbial dysbiosis is a hallmark of colorectal cancer, and infections have been linked to aberrant DNA methylation in cancers of the GI tract. To determine the microbiota’s impact on DNA methylation, we studied the DNA methylation of colorectal mucosa in germ-free (GF, no microbiome) and specific pathogen free (SPF, controlled microbiome) mice, as well as in interleukin 10 KO mice (Il10-/-) which are prone to inflammation and tumorigenesis in the presence of a microbiome. We compared DNA methylation changes to those seen in aging, and after exposure to the colon carcinogen azoxymethane (AOM). DNA methylation changes associated with aging were accelerated in the Il10-/- /SPF mice. By contrast, AOM induced profound hypomethylation that was distinct from the effects of aging or of the microbiome. CpG sites modified by the microbiome were over-represented among DNA methylation changes in colorectal cancer. Thus, the microbiome affects the DNA methylome of colorectal mucosa in patterns reminiscent of what is observed in colorectal cancer.
Project description:Background: Capecitabine-based adjuvant chemotherapy is the first-line treatment for patients with colorectal cancer (CRC). Although this therapy generally reduces the incidence of CRC recurrence and mortality, it can cause various chemotherapy-related adverse events (CRAEs), one of the most frequent of which is hand-foot syndrome (HFS). Most of the currently available HFS prediction markers focus on the pharmacokinetic parameters of drugs or their metabolites, yet our understanding of the biomolecular mechanism of HFS remains limited. Methods: We conducted an integrated multi-omics analysis of 63 Chinese patients with colorectal cancer (CRC) who had chemotherapy related adverse effect (CRAE) records during adjuvant chemotherapy. The metabolomic profiles for each of plasma, urine, and colorectal tissue as well as profiles for colorectal-tissue transcriptomics and genome methylation were analyzed based on samples collected before and during surgery. Results: Susceptibility to HFS was found to be associated with profibrotic changes in several aspects of cellular biochemistry and physiology, characterized by reduced nucleotide salvage (indicating potential tissue damage, elevated spermine release, increased M2 macrophage polarization, and hypermethylation of genes for collagen formation. All these aspects were found to promote fibrosis, even before patients received chemotherapeutic drugs or developed any HFS symptoms. Additionally, we developed and validated relevant biomarkers with reasonably good discrimination performance and a high AUROC (area under the receiver operating characteristic curve) value, i.e., from 0.848 to 1.000. Conclusions: Our results demonstrate that a profibrotic phenotype characterized by multi-omics variation in colorectal tissue, plasma, and urine is closely related to the susceptibility to chemotherapy-induced HFS. Our findings provide a better understanding of the molecular mechanism underlying HFS.
Project description:We performed an unbiased cell viability-based pooled shRNA screen on 59 cell lines to identify novel epigenetic and transcriptional dependencies of multiple cancer types, including leukemia, neuroblastoma, breast, colorectal, prostate, and rhabdoid tumors. Here, we identified Tricho-Rhino-Phalangeal Syndrome Type I protein (TRPS1) as one of the most significant hits specific for breast cancer cell lines. Downregulation of TRPS1 resulted in cell cycle arrest and apoptosis increase in vitro and impaired tumorigenic capacity in vivo. We characterized TRPS1 genomic targets and protein interactome. We identified GATAD2B as an important partner of TRPS1, uncovering novel epigenetic network crucial for breast cancer cell survival.
Project description:Within the ColoCare Project we obtained genome-wide DNA methylation profiles from 149 mucosa and 112 colorectal cancer tissues using Illumina HumanMethylation450k BeadChips. DNA methylation profiles were analysed by patient characteristics, lifestyle and exposures.
Project description:DNA methylation in colorectal cancer diagnosis. The Illumina GoldenGate Methylation Cancer Panel I was used to select a set of candidates markers informative of colorectal cancer diagnosis from 807 cancer-related genes. In the discovery phase, tumor tissue and paired adjacent normal mucosa from 92 colorectal patients were analyzed.
Project description:We performed comprehensive genome-scale DNA methylation profiling by Illumina Infinium HumanMethylation27 of 18 DNA pools that represent 84 colorectal cancer (CRC) samples divided according to their high-, intermediate-, and low-methylation epigenotypes (HME, IME, and LME, respectively) and 3 pools representing 70 normal-adjacent colonic tissues.
Project description:The discovery of cytosine hydroxymethylation (5-hmC) as a mechanism that potentially controls DNA methylation changes typical of neoplasia prompted us to investigate its behavior in colon cancer. 5-hmC is globally reduced in proliferating cells such as colon tumors and the gut crypt progenitors, from which tumors can arise. Here, we show that colorectal tumors and cancer cells express Ten-Eleven Translocation (TET) transcripts at levels similar to normal tissues. Genome-wide analyses show that promoters marked by 5-hmC in normal tissue, and those identified as TET2 targets in colorectal cancer cells, are resistant to methylation gain in cancer. In vitro studies of TET2 in cancer cells confirm that these promoters are resistant to methylation gain independently of sustained TET2 expression. We also find that a considerable number of the methylation gain-resistant promoters marked by 5-hmC in normal colon overlap with those that are marked with poised bivalent histone modifications in embryonic stem cells. Together our results indicate that promoters that acquire 5-hmC upon normal colon differentiation are innately resistant to neoplastic hypermethylation by mechanisms that do not require high levels of 5-hmC in tumors. Our study highlights the potential of cytosine modifications as biomarkers of cancerous cell proliferation.
Project description:The discovery of cytosine hydroxymethylation (5-hmC) as a mechanism that potentially controls DNA methylation changes typical of neoplasia prompted us to investigate its behavior in colon cancer. 5-hmC is globally reduced in proliferating cells such as colon tumors and the gut crypt progenitors, from which tumors can arise. Here, we show that colorectal tumors and cancer cells express Ten-Eleven Translocation (TET) transcripts at levels similar to normal tissues. Genome-wide analyses show that promoters marked by 5-hmC in normal tissue, and those identified as TET2 targets in colorectal cancer cells, are resistant to methylation gain in cancer. In vitro studies of TET2 in cancer cells confirm that these promoters are resistant to methylation gain independently of sustained TET2 expression. We also find that a considerable number of the methylation gain-resistant promoters marked by 5-hmC in normal colon overlap with those that are marked with poised bivalent histone modifications in embryonic stem cells. Together our results indicate that promoters that acquire 5-hmC upon normal colon differentiation are innately resistant to neoplastic hypermethylation by mechanisms that do not require high levels of 5-hmC in tumors. Our study highlights the potential of cytosine modifications as biomarkers of cancerous cell proliferation.