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
It has been demonstrated that patients with asthma have a large number of NK cells and show a stronger NK activity. These results indicate that NK cell activity may be related to total IgE level in serum in healthy su...It has been demonstrated that patients with asthma have a large number of NK cells and show a stronger NK activity. These results indicate that NK cell activity may be related to total IgE level in serum in healthy subjects. Previously,we have found that sodium butyrate (NaBu) markedly enhanced the IL- 4- induced IgE production in the LPS- stimulated murine splenocytes in vitro, and inductive rat IgE production in vivo, and enhanced the NK cell activity ex vivo .We hypothesized that the IgE production might be involved in butyrate- enhanced NK cell activity in vivo. Mice were intraperitoneally treated/immunized with NaBu or/and Ascaris suum extract (ASC),and the spleen NK cell activity was evaluated. Furthermore, the effect of serum (NAS) on IL- 2- or IFN-γ- induced spleen NK cell activity was determined. The spleen NK cell activity and IL- 2- or IFN-γ- induced spleen NK cell activity of mice treated/immunized with NaBu or/and ASC were stronger than those of untreated/unimmunized mice. Although IL- 4 blocked IL- 2 (100 U/ml)- or IFN-γ (100 U/ml)- induced increase in NK cell activity,these NK cell activities in mice treated/immunized with NaBu/ASC were not inhibited. IgE production showed a tendency to rise in NaBu- treated mice serum, and a synergistic effect was observed with treatment of NaBu and ASC. Moreover, the NAS significantly increased IL- 2(25 U/ml)- or IFN-γ (25 U/ml)- induced NK cell activity, and its effect was inhibited by anti- mouse IgE mAb. These data show that IgE plays an important role in NAS- enhanced IL- 2/IFN-γ- induced NK cell activity, and IL- 4 does not inhibit IgE and IL- 2/IFN-γ- induced NK cell activity in mice.展开更多
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.
文摘It has been demonstrated that patients with asthma have a large number of NK cells and show a stronger NK activity. These results indicate that NK cell activity may be related to total IgE level in serum in healthy subjects. Previously,we have found that sodium butyrate (NaBu) markedly enhanced the IL- 4- induced IgE production in the LPS- stimulated murine splenocytes in vitro, and inductive rat IgE production in vivo, and enhanced the NK cell activity ex vivo .We hypothesized that the IgE production might be involved in butyrate- enhanced NK cell activity in vivo. Mice were intraperitoneally treated/immunized with NaBu or/and Ascaris suum extract (ASC),and the spleen NK cell activity was evaluated. Furthermore, the effect of serum (NAS) on IL- 2- or IFN-γ- induced spleen NK cell activity was determined. The spleen NK cell activity and IL- 2- or IFN-γ- induced spleen NK cell activity of mice treated/immunized with NaBu or/and ASC were stronger than those of untreated/unimmunized mice. Although IL- 4 blocked IL- 2 (100 U/ml)- or IFN-γ (100 U/ml)- induced increase in NK cell activity,these NK cell activities in mice treated/immunized with NaBu/ASC were not inhibited. IgE production showed a tendency to rise in NaBu- treated mice serum, and a synergistic effect was observed with treatment of NaBu and ASC. Moreover, the NAS significantly increased IL- 2(25 U/ml)- or IFN-γ (25 U/ml)- induced NK cell activity, and its effect was inhibited by anti- mouse IgE mAb. These data show that IgE plays an important role in NAS- enhanced IL- 2/IFN-γ- induced NK cell activity, and IL- 4 does not inhibit IgE and IL- 2/IFN-γ- induced NK cell activity in mice.