1. Rescuing Dicer expression in inflamed colon tissues alleviates colitis and prevents colitis-associated tumorigenesis
- Author
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Guanbin Song, Lingli Zhou, Shouhui Zhong, Lin-Jie Wei, Zhechao Zhang, Xiao Chen, Xiaoli Wu, Hui Liu, Yunsheng Xu, Qin He, Yi Jin, Zhong-Wei He, Youchun Lei, Kai-Fu Tang, Wenjun Yang, Rongying Ou, Jian Gao, Zheng Wang, and Wei-Yun Wang
- Subjects
0301 basic medicine ,Male ,Ribonuclease III ,Berberine ,Carcinogenesis ,genetic processes ,Medicine (miscellaneous) ,Gene Expression ,medicine.disease_cause ,DEAD-box RNA Helicases ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,Gene expression ,Intestinal Mucosa ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) ,biology ,Pranoprofen ,food and beverages ,Colitis ,Cell Transformation, Neoplastic ,030220 oncology & carcinogenesis ,medicine.symptom ,Research Paper ,Signal Transduction ,DNA damage ,Colon ,anastrozole ,Inflammation ,03 medical and health sciences ,colitis-associated carcinogenesis ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Azoxymethane ,fungi ,medicine.disease ,pranoprofen ,Mice, Inbred C57BL ,enzymes and coenzymes (carbohydrates) ,MicroRNAs ,Oxidative Stress ,030104 developmental biology ,chemistry ,Gene Expression Regulation ,biology.protein ,Cancer research ,Dicer - Abstract
Chronic inflammation is known to promote carcinogenesis; Dicer heterozygous mice are more likely to develop colitis-associated tumors. This study investigates whether Dicer is downregulated in inflamed colon tissues before malignancy occurs and whether increasing Dicer expression in inflamed colon tissues can alleviate colitis and prevent colitis-associated tumorigenesis. Methods: Gene expression in colon tissues was analyzed by immunohistochemistry, immunoblots, and real-time RT-PCR. Hydrogen peroxide or N-acetyl-L-cysteine was used to induce or alleviate oxidative stress, respectively. Mice were given azoxymethane followed by dextran sulfate sodium to induce colitis and colon tumors. Berberine, anastrozole, or pranoprofen was used to rescue Dicer expression in inflammatory colon tissues. Results: Oxidative stress repressed Dicer expression in inflamed colon tissues by inducing miR-215 expression. Decreased Dicer expression increased DNA damage and cytosolic DNA and promoted interleukin-6 expression upon hydrogen peroxide treatment. Dicer overexpression in inflamed colon tissues alleviated inflammation and repressed colitis-associated carcinogenesis. Furthermore, we found that anastrozole, berberine, and pranoprofen could promote Dicer expression and protect cells from hydrogen peroxide-induced DNA damage, thereby reducing cytosolic DNA and partially repressing interleukin-6 expression upon hydrogen peroxide treatment. Rescuing Dicer expression using anastrozole, berberine, or pranoprofen in inflamed colon tissues alleviated colitis and prevented colitis-associated tumorigenesis. Conclusions: Dicer was downregulated in inflamed colon tissues before malignancy occurred. Decreased Dicer expression further exaggerated inflammation, which may promote carcinogenesis. Anastrozole, berberine, and pranoprofen alleviated colitis and colitis-associated tumorigenesis by promoting Dicer expression. Our study provides insight into potential colitis treatment and colitis-associated colon cancer prevention strategies.
- Published
- 2020