Objective: Tumor metastasis is a complex, multistep process that depends on tumor cells and their communication with the tumor microenvironment. A p53 gain-of-function mutant has been shown to enhance the tumorigenesi...Objective: Tumor metastasis is a complex, multistep process that depends on tumor cells and their communication with the tumor microenvironment. A p53 gain-of-function mutant has been shown to enhance the tumorigenesis, invasion, and metastasis abilities of tumor cells. This study aimed to investigate the roles of p53 R273 H mutation in the tumor microenvironment.Methods: The in vitro and in vivo effects of the p53 R273 H mutant on the invasion and metastasis of HCT116 cells were investigated. Exosomes from wild-type and HCT116-TP53(R273 H) cells were cocultured with mouse embryonic fibroblasts(MEFs). The roles of differentially expressed exosomal micro RNAs identified by microarray analysis were investigated. The functions of the p53 R273 H mutant in tumor cells were also investigated via gene expression microarray and quantitative polymerase chain reaction(q PCR) analyses.Results: Introducing p53 R273 H mutant into HCT116 cells significantly potentiated pulmonary metastasis in vivo. In the presence of exosomes derived from HCT116-TP53(R273 H) cells, the exosomes were taken up by MEFs and became activated. Microarray analysis showed that the p53 R273 H mutation increased the exosomal levels of mi R-21-3 p and mi R-769-3 p. Intriguingly, in clinical samples, mi R-21-3 p and mi R-769-3 p levels were significantly higher in patients with a p53 mutation than in those without this mutation. Furthermore, both mi R-21-3 p and mi R-769-3 p activated fibroblasts and exerted a synergistic effect via their target genes on the transforming growth factor-β(TGF-β)/Smad signaling pathway. The activated fibroblasts excreted cytokine TGF-β and may have reciprocally induced cancer cells to undergo epithelial-mesenchymal transition(EMT). Indeed, HCT116-TP53(R273 H) cells showed increased expression of ZEB1 and SNAI2 and decreased transcription of several cell adhesion molecules.Conclusions: The mutant p53-exosomal mi R-21-3 p/mi R-769-3 p-fibroblast-cytokine circuit appears to be responsible for communication between tumor and stromal cells, with exosomal mi RNAs acting as a bridge. mi R-21-3 p and mi R-769-3 p are potential predictive markers of pulmonary metastasis and candidate targets for therapeutic interventions.展开更多
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
基金supported by grants from the National Key R & D Program of China (No. 2017YFC0906601, No. 2017ZX10203205-003-001 and No. 2016YFC0901403)the National Natural Science Foundation (No. 81572840, No. 81572365, No. 81728015 and No. 81872033)+1 种基金the Nonprofit Central Research Institute Fund of CAMS (No. 2018RC310011)the CAMS Innovation Fund for Medical Sciences (No. 2016-I2M-1-001, No. 2017-I2M-3005 and No. 2019-I2M-1-003) in China
文摘Objective: Tumor metastasis is a complex, multistep process that depends on tumor cells and their communication with the tumor microenvironment. A p53 gain-of-function mutant has been shown to enhance the tumorigenesis, invasion, and metastasis abilities of tumor cells. This study aimed to investigate the roles of p53 R273 H mutation in the tumor microenvironment.Methods: The in vitro and in vivo effects of the p53 R273 H mutant on the invasion and metastasis of HCT116 cells were investigated. Exosomes from wild-type and HCT116-TP53(R273 H) cells were cocultured with mouse embryonic fibroblasts(MEFs). The roles of differentially expressed exosomal micro RNAs identified by microarray analysis were investigated. The functions of the p53 R273 H mutant in tumor cells were also investigated via gene expression microarray and quantitative polymerase chain reaction(q PCR) analyses.Results: Introducing p53 R273 H mutant into HCT116 cells significantly potentiated pulmonary metastasis in vivo. In the presence of exosomes derived from HCT116-TP53(R273 H) cells, the exosomes were taken up by MEFs and became activated. Microarray analysis showed that the p53 R273 H mutation increased the exosomal levels of mi R-21-3 p and mi R-769-3 p. Intriguingly, in clinical samples, mi R-21-3 p and mi R-769-3 p levels were significantly higher in patients with a p53 mutation than in those without this mutation. Furthermore, both mi R-21-3 p and mi R-769-3 p activated fibroblasts and exerted a synergistic effect via their target genes on the transforming growth factor-β(TGF-β)/Smad signaling pathway. The activated fibroblasts excreted cytokine TGF-β and may have reciprocally induced cancer cells to undergo epithelial-mesenchymal transition(EMT). Indeed, HCT116-TP53(R273 H) cells showed increased expression of ZEB1 and SNAI2 and decreased transcription of several cell adhesion molecules.Conclusions: The mutant p53-exosomal mi R-21-3 p/mi R-769-3 p-fibroblast-cytokine circuit appears to be responsible for communication between tumor and stromal cells, with exosomal mi RNAs acting as a bridge. mi R-21-3 p and mi R-769-3 p are potential predictive markers of pulmonary metastasis and candidate targets for therapeutic interventions.
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.
