In vitro and in silico mechanistic insights into miR-21-5p-mediated topoisomerase drug resistance in human colorectal cancer cells
Journal
Biomolecules
Journal Volume
9
Journal Issue
9
Date Issued
2019
Author(s)
Abstract
Although chemotherapy for treating colorectal cancer has had some success, drug resistance and metastasis remain the major causes of death for colorectal cancer patients. MicroRNA-21-5p (hereafter denoted as miR-21) is one of the most abundant miRNAs in human colorectal cancer. A Kaplan-Meier survival analysis found a negative prognostic correlation of miR- 21 and metastasis-free survival in colorectal cancer patients (The Cancer Genome Atlas Colon Adenocarcinoma/TCGA-COAD cohort). To explore the role of miR-21 overexpression in drug resistance, a stable miR-21-overexpressing clone in a human DLD-1 colorectal cancer cell line was established. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) cell viability assay found that miR-21 overexpression induced drug resistance to topoisomerase inhibitors (SN- 38, doxorubicin, and etoposide/VP-16). Mechanistically, we showed that miR-21 overexpression reduced VP-16-induced apoptosis and concomitantly enhanced pro-survival autophagic flux without the alteration of topoisomerase expression and activity. Bioinformatics analyses suggested that miR-21 overexpression induced genetic reprogramming that mimicked the gene signature of topoisomerase inhibitors and downregulated genes related to the proteasome pathway. Taken together, our results provide a novel insight into the role of miR-21 in the development of drug resistance in colorectal cancer. ? 2019 by the authors. Licensee MDPI, Basel, Switzerland.
Subjects
caspase 3; complementary DNA; DNA topoisomerase inhibitor; doxorubicin; etoposide; firtecan; fluorouracil; messenger RNA; microRNA 21; microRNA 21 5p; nicotinamide adenine dinucleotide adenosine diphosphate ribosyltransferase 1; proteasome; unclassified drug; DNA topoisomerase; DNA topoisomerase inhibitor; microRNA; MIRN21 microRNA, human; apoptosis; Article; autophagy; bioinformatics; cancer patient; cancer prognosis; cancer resistance; cancer survival; cell proliferation; cell viability; cell viability assay; cohort analysis; colorectal cancer cell line; computer model; DLD-1 cell line; down regulation; enzyme activity; gene overexpression; human; human cell; in vitro study; major clinical study; metastasis free survival; nuclear reprogramming; overall survival; stable expression; upregulation; autophagy; colorectal tumor; computer simulation; drug effect; drug resistance; gene expression regulation; genetics; metabolism; pathology; tumor cell line; Autophagy; Cell Line, Tumor; Colorectal Neoplasms; Computer Simulation; DNA Topoisomerases; Drug Resistance, Neoplasm; Gene Expression Regulation, Neoplastic; Humans; MicroRNAs; Topoisomerase Inhibitors
SDGs
Type
journal article