The human intestinal microbiome plays a major role in human health and diseases, including colorectal cancer. Colorectal carcinogenesis represents a heterogeneous process with a differing set of somatic molecular alte...The human intestinal microbiome plays a major role in human health and diseases, including colorectal cancer. Colorectal carcinogenesis represents a heterogeneous process with a differing set of somatic molecular alterations, influenced by diet, environmental and microbial exposures, and host immunity. Fusobacterium species are part of the human oral and intestinal microbiota. Metagenomic analyses have shown an enrichment of Fusobacterium nucleatum(F. nucleatum) in colorectal carcinoma tissue. Using 511 colorectal carcinomas from Japanese patients, we assessed the presence of F. nucleatum. Our results showed that the frequency of F. nucleatum positivity in the Japanese colorectal cancer was 8.6%(44/511), which was lower than that in United States cohort studies(13%). Similar to the United States studies, F. nucleatum positivityin Japanese colorectal cancers was significantly associated with microsatellite instability(MSI)-high status. Regarding the immune response in colorectal cancer, high levels of infiltrating T-cell subsets(i.e., CD3+, CD8+, CD45RO+, and FOXP3+ cells) have been associated with better patient prognosis. There is also evidence to indicate that molecular features of colorectal cancer, especially MSI, influence T-cell-mediated adaptive immunity. Concerning the association between the gut microbiome and immunity, F. nucleatum has been shown to expand myeloid-derived immune cells, which inhibit T-cell proliferation and induce T-cell apoptosis in colorectal cancer. This finding indicates that F. nucleatum possesses immunosuppressive activities by inhibiting human T-cell responses. Certain micro RNAs are induced during the macrophage inflammatory response and have the ability to regulate host-cell responses to pathogens. Micro RNA-21 increases the levels of IL-10 and prostaglandin E2, which suppress antitumor T-cell-mediated adaptive immunity through the inhibition of the antigen-presenting capacities of dendritic cells and T-cell proliferation in colorectal cancer cells. Thus, emerging evidence may provide insights for strategies to target microbiota, immune cells and tumor molecular alterations for colorectal cancer prevention and treatment. Further investigation is needed to clarify the association of Fusobacterium with T-cells and micro RNA expressions in colorectal cancer.展开更多
MicroRNAs have been increasingly recognized as useful biomarkers for colorectal cancers(CRC).We have recently observed that microRNA-31(miR-31)expression is associated with BRAF mutation and prognosis in CRC.Moreover,...MicroRNAs have been increasingly recognized as useful biomarkers for colorectal cancers(CRC).We have recently observed that microRNA-31(miR-31)expression is associated with BRAF mutation and prognosis in CRC.Moreover,high miR-31 expression is frequently detected in sessile serrated adenomas compared with hyperplastic polyps(HPs).These results suggest that miR-31 may contribute to the progression of serrated lesions.At a follow-up colonoscopy,we observed the case of a 75-year-old man with a 7-mm flat-elevated lesion in the cecum and diagnosed the lesion as an early invasive carcinoma with serrated features.Tissue specimens were obtained from the representative areas to compare the molecular alterations in the carcinoma component with those in the HP component.Higher miR-31 expression was observed in the carcinoma component(57-fold increase)and the HP component(8-fold increase)compared with the paired normal mucosa,suggesting that miR-31 may be one of the key molecules in serrated pathway progression.展开更多
AIM: To investigate insulin-like growth factor 2 (IGF2) differentially methylated region (DMR)0 hypomethylation in relation to clinicopathological and molecular features in colorectal serrated lesions.
基金Supported by Japanese Society of Gastroenterology Research Foundation(to Nosho K)Pancreas Research Foundation of Japan(to Nosho K)+4 种基金Medical Research Encouragement Prize of The Japan Medical Association(to Nosho K)The Japan Society for the Promotion of Science Challenging Exploratory Researchgrant No.25670371(to Shinomura Y)Ono Cancer Research Foundation(to Ito M)
文摘The human intestinal microbiome plays a major role in human health and diseases, including colorectal cancer. Colorectal carcinogenesis represents a heterogeneous process with a differing set of somatic molecular alterations, influenced by diet, environmental and microbial exposures, and host immunity. Fusobacterium species are part of the human oral and intestinal microbiota. Metagenomic analyses have shown an enrichment of Fusobacterium nucleatum(F. nucleatum) in colorectal carcinoma tissue. Using 511 colorectal carcinomas from Japanese patients, we assessed the presence of F. nucleatum. Our results showed that the frequency of F. nucleatum positivity in the Japanese colorectal cancer was 8.6%(44/511), which was lower than that in United States cohort studies(13%). Similar to the United States studies, F. nucleatum positivityin Japanese colorectal cancers was significantly associated with microsatellite instability(MSI)-high status. Regarding the immune response in colorectal cancer, high levels of infiltrating T-cell subsets(i.e., CD3+, CD8+, CD45RO+, and FOXP3+ cells) have been associated with better patient prognosis. There is also evidence to indicate that molecular features of colorectal cancer, especially MSI, influence T-cell-mediated adaptive immunity. Concerning the association between the gut microbiome and immunity, F. nucleatum has been shown to expand myeloid-derived immune cells, which inhibit T-cell proliferation and induce T-cell apoptosis in colorectal cancer. This finding indicates that F. nucleatum possesses immunosuppressive activities by inhibiting human T-cell responses. Certain micro RNAs are induced during the macrophage inflammatory response and have the ability to regulate host-cell responses to pathogens. Micro RNA-21 increases the levels of IL-10 and prostaglandin E2, which suppress antitumor T-cell-mediated adaptive immunity through the inhibition of the antigen-presenting capacities of dendritic cells and T-cell proliferation in colorectal cancer cells. Thus, emerging evidence may provide insights for strategies to target microbiota, immune cells and tumor molecular alterations for colorectal cancer prevention and treatment. Further investigation is needed to clarify the association of Fusobacterium with T-cells and micro RNA expressions in colorectal cancer.
基金Supported by Japan Society for the Promotion of Science(JSPS)Grant-in-Aid for Scientific Research,grant No.23790800(to Nosho K)A-STEP(Adaptable and Seamless Technology Transfer Program through Target-driven R and D)(to Nosho K)
文摘MicroRNAs have been increasingly recognized as useful biomarkers for colorectal cancers(CRC).We have recently observed that microRNA-31(miR-31)expression is associated with BRAF mutation and prognosis in CRC.Moreover,high miR-31 expression is frequently detected in sessile serrated adenomas compared with hyperplastic polyps(HPs).These results suggest that miR-31 may contribute to the progression of serrated lesions.At a follow-up colonoscopy,we observed the case of a 75-year-old man with a 7-mm flat-elevated lesion in the cecum and diagnosed the lesion as an early invasive carcinoma with serrated features.Tissue specimens were obtained from the representative areas to compare the molecular alterations in the carcinoma component with those in the HP component.Higher miR-31 expression was observed in the carcinoma component(57-fold increase)and the HP component(8-fold increase)compared with the paired normal mucosa,suggesting that miR-31 may be one of the key molecules in serrated pathway progression.
基金Supported by The Japan Society for the Promotion of Science(JSPS)Grant-in-Aid for Scientific Research,grant No.23790800(to Nosho K)and 23390200(to Shinomura Y)A-STEP(Adaptable and Seamless Technology Transfer Program through Targetdriven R and D)(to Nosho K)+4 种基金Daiwa Securities Health Foundation(to Nosho K)Kobayashi Foundation for Cancer Research(to Nosho K)Sagawa Foundation for Promotion of Cancer Research(to Nosho K)Suzuken Memorial Foundation(to Nosho K),and Takeda Science Foundation(to Nosho K)USA National Institute of Health,grant number R01 CA151993(to Ogino S)
文摘AIM: To investigate insulin-like growth factor 2 (IGF2) differentially methylated region (DMR)0 hypomethylation in relation to clinicopathological and molecular features in colorectal serrated lesions.
