1. Upregulation of polycistronic microRNA-143 and microRNA-145 in colonocytes suppresses colitis and inflammation-associated colon cancer
- Author
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Vani J. Konda, Sonia S. Kupfer, Urszula Dougherty, Vijaya L. Rao, Tong-Chuan He, John Hart, Xiaorong Zhu, Fang He, Diana C. West-Szymanski, Zifeng Deng, Nader Amini, Loren Joseph, Stephen C. Meredith, Alessandro Fichera, Fatma Ayaloglu-Butun, Yan Chun Li, Akushika Kwesi, Arantxa Sanchez, Reba Mustafi, Marc Bissonnette, Hongyan Zhu, Michelle Fletcher, Joel Pekow, Dilip K. Deb, and Atsushi Sakuraba
- Subjects
0301 basic medicine ,Cancer Research ,Colorectal cancer ,Down-Regulation ,Inflammation ,Karyopherins ,Biology ,medicine.disease_cause ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Downregulation and upregulation ,microRNA ,medicine ,Animals ,Humans ,Colitis ,Molecular Biology ,Messenger RNA ,Azoxymethane ,DNA Methylation ,medicine.disease ,Up-Regulation ,Gene Expression Regulation, Neoplastic ,MicroRNAs ,030104 developmental biology ,chemistry ,030220 oncology & carcinogenesis ,Colonic Neoplasms ,Cancer research ,medicine.symptom ,Carcinogenesis ,Research Paper - Abstract
Because ADAM17 promotes colonic tumorigenesis, we investigated potential miRNAs regulating ADAM17; and examined effects of diet and tumorigenesis on these miRNAs. We also examined pre-miRNA processing and tumour suppressor roles of several of these miRNAs in experimental colon cancer. Using TargetScan, miR-145, miR-148a, and miR-152 were predicted to regulate ADAM17. miR-143 was also investigated as miR-143 and miR-145 are co-transcribed and associated with decreased tumour growth. HCT116 colon cancer cells (CCC) were co-transfected with predicted ADAM17-regulating miRNAs and luciferase reporters controlled by ADAM17-3’UTR. Separately, pre-miR-143 processing by colonic cells was measured. miRNAs were quantified by RT-PCR. Tumours were induced with AOM/DSS in WT and transgenic mice (Tg) expressing pre-miR-143/miR-145 under villin promoter. HCT116 transfection with miR-145, −148a or −152, but not scrambled miRNA inhibited ADAM17 expression and luciferase activity. The latter was suppressed by mutations in ADAM17-3’UTR. Lysates from colonocytes, but not CCC, processed pre-miR-143 and mixing experiments suggested CCC lacked a competency factor. Colonic miR-143, miR-145, miR-148a, and miR-152 were downregulated in tumours and more moderately by feeding mice a Western diet. Tg mice were resistant to DSS colitis and had significantly lower cancer incidence and tumour multiplicity. Tg expression blocked up-regulation of putative targets of miR-143 and miR-145, including ADAM17, K-Ras, XPO5, and SET. miR-145, miR-148a, and miR-152 directly suppress colonocyte ADAM17 and are down-regulated in colon cancer. This is the first direct demonstration of tumour suppressor roles for miR-143 and miR-145 in an in vivo model of colonic tumorigenesis.
- Published
- 2020
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