Ronghua Liu1, Zhou Lu1, Jie Gu2, Jiajing Liu1, Enyu Huang1, Xiaoming Liu3, Luman Wang1, Jiao Yang4, Yuting Deng4, Jiawen Qian4, Feifei Luo4, Zhiming Wang1, Hushan Zhang1, Xuechao Jiang1, Dan Zhang1, Jing Qian1, Guangwei Liu1, Hongguang Zhu5, Youcun Qian6, Zhanju Liu7, Yiwei Chu8. 1. Department of Immunology, School of Basic Medical Sciences, and Institute of Biomedical Sciences, Fudan University, Shanghai, P.R. China. 2. Department of Thoracic Surgery, The Affiliated Zhongshan Hospital of Fudan University, Shanghai, P.R. China. 3. Department of Dermatology, Shenzhen Hospital, Peking University, Shenzhen, Guangdong, P.R. China. 4. Biotherapy Research Center, Fudan University, Shanghai, P.R. China. 5. Division of Surgical Pathology, Huashan Hospital, Fudan University, Shanghai, P.R. China. 6. Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Shanghai, P.R. China. 7. Department of Gastroenterology, The Shanghai Tenth People's Hospital, Tongji University, Shanghai, P.R. China. 8. Department of Immunology, School of Basic Medical Sciences, and Institute of Biomedical Sciences, Fudan University, Shanghai, P.R. China; Biotherapy Research Center, Fudan University, Shanghai, P.R. China. Electronic address: yiwei_chu@126.com.
Abstract
BACKGROUND & AIMS: B cells infiltrate tumors, but little is known about how they affect tumor growth and progression. microRNA15A (MIR15A or miRNA15A) and microRNA16-1 (MIR16-1 or miRNA16-1) regulate cell proliferation, apoptosis, and drug resistance. We investigated their involvement in B-cell-mediated immune suppression by colorectal tumors. METHODS: Mice with disruptions of the gene cluster that encodes MIR15A and MIR16-1 (knockout mice), and control (C57BL/B6) mice were given azoxymethane with dextran sodium sulfate (AD) to induce formation of colorectal tumors. Mice were given anti-CD20 to delete B cells, or injections of agomir to increase MIR15A and MIR16-1. Proliferation of CD8+T cells was measured by carboxyfluorescein-succinimidyl-ester analysis. Colon tissues were collected from mice and analyzed by flow cytometry, microRNA (miRNA) sequencing, and for cytokine production. Intestinal epithelial cells (IECs) were isolated and transfected with miRNA mimics, to identify their targets. We analyzed miRNA expression patterns and quantified B cells in colorectal cancer tissue microarrays derived from 90 patients who underwent surgical resection, from July 2006 through April 2008, in Shanghai, China; expression data were compared with clinical outcomes. RESULTS: Tumors that developed in knockout mice following administration of AD were larger and contained greater numbers of B cells than tumors that grew in control mice. Most of the B cells in the tumors were positive for immunoglobulin A (IgA+). IgA+ B cells expressed high levels of immune regulatory molecules (programmed death ligand 1, interleukin 10, and transforming growth factor beta), and repressed the proliferation and activation of CD8+ T cells. Levels of MIR15A and MIR16-1 were reduced in colon tumors from mice, compared with nontumor colon tissue. Incubation of IECs with IL17A reduced expression of MIR15A and MIR16-1. Transgenic expression of MIR15A and MIR16-1 in IECs decreased activation of NF-κB and STAT1 by reducing expression of I-kappaB kinases; this resulted in reduced production of chemokine (C-X-C motif) ligands 9 and 10 and decreased chemotaxis of IgA+ B cells. Tumors in mice injected with AD and agomir grew more slowly than tumors in mice not given in agomir and contained fewer IgA+ B cells. We found a negative correlation between levels of MIR15A and MIR16-1 and numbers of IgA+B cells in human colorectal tumor tissues; high levels of MIR15A and MIR16-1 and low numbers of IgA+B cells were associated with longer survival times of patients. CONCLUSIONS: We found increased levels of MIR15A and MIR16-1 to reduce numbers of IgA+ B cells in colorectal tumor tissues and correlate with increased survival time of patients. In mice that lack MIR15A and MIR16-1, colon tumors grow more rapidly and contain increased numbers of IgA+ B cells. MIR15A and MIR16-1 appear to activate signaling pathways required for B-cell-mediated immune suppression.
BACKGROUND & AIMS: B cells infiltrate tumors, but little is known about how they affect tumor growth and progression. microRNA15A (MIR15A or miRNA15A) and microRNA16-1 (MIR16-1 or miRNA16-1) regulate cell proliferation, apoptosis, and drug resistance. We investigated their involvement in B-cell-mediated immune suppression by colorectal tumors. METHODS:Mice with disruptions of the gene cluster that encodes MIR15A and MIR16-1 (knockout mice), and control (C57BL/B6) mice were given azoxymethane with dextran sodium sulfate (AD) to induce formation of colorectal tumors. Mice were given anti-CD20 to delete B cells, or injections of agomir to increase MIR15A and MIR16-1. Proliferation of CD8+T cells was measured by carboxyfluorescein-succinimidyl-ester analysis. Colon tissues were collected from mice and analyzed by flow cytometry, microRNA (miRNA) sequencing, and for cytokine production. Intestinal epithelial cells (IECs) were isolated and transfected with miRNA mimics, to identify their targets. We analyzed miRNA expression patterns and quantified B cells in colorectal cancer tissue microarrays derived from 90 patients who underwent surgical resection, from July 2006 through April 2008, in Shanghai, China; expression data were compared with clinical outcomes. RESULTS:Tumors that developed in knockout mice following administration of AD were larger and contained greater numbers of B cells than tumors that grew in control mice. Most of the B cells in the tumors were positive for immunoglobulin A (IgA+). IgA+ B cells expressed high levels of immune regulatory molecules (programmed death ligand 1, interleukin 10, and transforming growth factor beta), and repressed the proliferation and activation of CD8+ T cells. Levels of MIR15A and MIR16-1 were reduced in colon tumors from mice, compared with nontumor colon tissue. Incubation of IECs with IL17A reduced expression of MIR15A and MIR16-1. Transgenic expression of MIR15A and MIR16-1 in IECs decreased activation of NF-κB and STAT1 by reducing expression of I-kappaB kinases; this resulted in reduced production of chemokine (C-X-C motif) ligands 9 and 10 and decreased chemotaxis of IgA+ B cells. Tumors in mice injected with AD and agomir grew more slowly than tumors in mice not given in agomir and contained fewer IgA+ B cells. We found a negative correlation between levels of MIR15A and MIR16-1 and numbers of IgA+B cells in humancolorectal tumor tissues; high levels of MIR15A and MIR16-1 and low numbers of IgA+B cells were associated with longer survival times of patients. CONCLUSIONS: We found increased levels of MIR15A and MIR16-1 to reduce numbers of IgA+ B cells in colorectal tumor tissues and correlate with increased survival time of patients. In mice that lack MIR15A and MIR16-1, colon tumors grow more rapidly and contain increased numbers of IgA+ B cells. MIR15A and MIR16-1 appear to activate signaling pathways required for B-cell-mediated immune suppression.
Authors: Daniel Triner; Samantha N Devenport; Sadeesh K Ramakrishnan; Xiaoya Ma; Ryan A Frieler; Joel K Greenson; Naohiro Inohara; Gabriel Nunez; Justin A Colacino; Richard M Mortensen; Yatrik M Shah Journal: Gastroenterology Date: 2018-12-11 Impact factor: 22.682
Authors: Estefanía R Zacca; Luisina I Onofrio; Cristina D V Acosta; Paola V Ferrero; Sergio M Alonso; María C Ramello; Eduardo Mussano; Laura Onetti; Isaac I Cadile; Maria I Stancich; Maria C Taboada Bonfanti; Carolina L Montes; Eva V Acosta Rodríguez; Adriana Gruppi Journal: Front Immunol Date: 2018-10-01 Impact factor: 7.561