Bifidobacterium Infantis Ameliorates Chemotherapy-Induced Intestinal Mucositis Via Regulating T Cell Immunity in Colorectal Cancer Rats
CELLULAR PHYSIOLOGY AND BIOCHEMISTRY
Authors: Mi, Hui; Dong, Yan; Zhang, Bin; Wang, Haonan; Peter, Chung C. K.; Gao, Ping; Fu, Hong; Gao, Yajie
Abstract
Background/Aims: Intestinal mucositis (IM) is a commonly encountered side effect in cancer patients receiving chemotherapy. This study aimed to investigate the effect of Bifidobacterium infantis (B. infantis) in attenuating the severity of chemotherapy-induced intestinal mucositis by regulating the T cell subsets in rats with colorectal cancer (CRC). Methods: Thirty male Sprague-Dawley (SD) rats were injected dimethyl hydrazine (DMH) subcutaneously for 10 weeks, and then injected SW480 cells in rectal mucosa to create a CRC model, and the rats were randomly divided into three groups: Control group (saline + saline), Chemotherapy group (saline + 5-FU+Oxaliplatin), B. infantis group (B. infantis + 5-FU + Oxaliplatin). IM was evaluated based on diarrhea severity, intestinal villus height, crypt depth, pro-inflammatory cytokines (IL-6, IL-1 beta, TNF-alpha), T cell subsets (CD4(+) 117A(+) cells and CD4(+) CD25(+) Foxp3(+) Tregs) and related cytokine profiles. Results:The results showed that the B. infantis group demonstrated a higher body weight (BW) and intestinal villus height and a deeper crypt depth compared to the Chemotherapy group. The level of IL-6, IL-1 beta and TNF-alpha which increased by chemotherapy, was lowered by B. infantis administration. Real time reverse transcription- polymerase chain reaction (RT-PCR) showed B. infantis reduced relative expression of Th17 and Th1 cells related cytokines, and increased relative expression of CD4(+) CD25(+) Foxp3(+) Tregs related cytokines. Furthermore, Flow cytometry analysis showed B. infantis reduced CD4(+) IL17A(+) cells and increased CD4(+) CD25(+) Foxp3(+) Tregs in mesenteric lymph nodes (MLNs) compared to the Chemotherapy group. Conclusion: B. infantis effectively attenuates chemotherapy-induced intestinal mucositis by decreasing Th1 and Th17 response and increasing CD4(+) CD25(+) Foxp3(+) Tregs response.
Fusobacterium Nucleatum Subspecies Animalis Influences Proinflammatory Cytokine Expression and Monocyte Activation in Human Colorectal Tumors
CANCER PREVENTION RESEARCH
Authors: Ye, Xiangcang; Wang, Rui; Bhattacharya, Rajat; Boulbes, Delphine R.; Fan, Fan; Xia, Ling; Adoni, Harish; Ajami, Nadim J.; Wong, Matthew C.; Smith, Daniel P.; Petrosino, Joseph F.; Venable, Susan; Qiao, Wei; Baladandayuthapani, Veera; Maru, Dipen; Ellis, Lee M.
Abstract
Chronic infection and associated inflammation have long been suspected to promote human carcinogenesis. Recently, certain gut bacteria, including some in the Fusobacterium genus, have been implicated in playing a role in human colorectal cancer development. However, the Fusobacterium species and subspecies involved and their oncogenic mechanisms remain to be determined. We sought to identify the specific Fusobacterium spp. and ssp. in clinical colorectal cancer specimens by targeted sequencing of Fusobacterium 16S ribosomal RNA gene. Five Fusobacterium spp. were identified in clinical colorectal cancer specimens. Additional analyses confirmed that Fusobacterium nucleatum ssp. animalis was the most prevalent F. nucleatum subspecies in human colorectal cancers. We also assessed inflammatory cytokines in colorectal cancer specimens using immunoassays and found that expression of the cytokines IL17A and TNF alpha was markedly increased but IL21 decreased in the colorectal tumors. Furthermore, the chemokine (C-C motif) ligand 20 was differentially expressed in colorectal tumors at all stages. In in vitro coculture assays, F. nucleatum ssp. animalis induced CCL20 protein expression in colorectal cancer cells and monocytes. It also stimulated the monocyte/macrophage activation and migration. Our observations suggested that infection with F. nucleatum ssp. animalis in colorectal tissue could induce inflammatory response and promote colorectal cancer development. Further studies are warranted to determine if F. nucleatum ssp. animalis could be a novel target for colorectal cancer prevention and treatment. (C) 2017 AACR.