title: MiR-99a and MiR-491 Regulate Cisplatin Resistance in Human Gastric Cancer Cells by Targeting CAPNS1.
abstract: Cisplatin is the first-line agent utilized for the clinical treatment of a wide variety of solid tumors including gastric cancer. However, the intrinsic or acquired cisplatin resistance is often occurred in patients with gastric cancer and resulted in failure of cisplatin therapy. In order to investigate if miRNA involves in cisplatin resistance of human gastric cancer, we first screened and compared the expression of miRNAs between cisplatin resistant gastric cancer cell lines SGC-7901/DDP and BGC-823/DDP and their sensitive parental cells by miRNAs microarray and followed by analysis of 2D-GE/MS to identify their target proteins. We found both miR-99a and miR-491 were upregulated while their target gene calpain small subunit 1 (CAPNS1) was downregulated in resistant gastric cancer cells. Dual-luciferase- reporter assays with wild-type and mutated CAPNS1 3'-UTR confirmed their specificity of targeting. Inhibition of miR-99a and miR-491, or overexpress CAPNS1 can enhance cisplatin sensitivity of the resistant cells while transfection of two miRNAs' mimics or si-CAPNS1 in the sensitive cells can induce their resistance. Moreover, our results demonstrated CAPNS1 positively regulated calpain1 and calpain2, the catalytic subunits of CAPNS1, and cleaved caspase3 which further cleaved PARP1 and directly induced apoptosis. Therefore, miR-99a and miR-491 might be work as novel molecules regulate cisplatin resistance by directly targeting CAPNS1 associated pathway in human gastric cancer cells.
authors.affiliation: Department of Cell Biology, School of Basic Medical Sciences, Nanjing Medical University.
authors.forename: Yajie
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Molecular Cell Biology and Toxicology, School of Public Health, Nanjing Medical University; Laboratory of Cancer Biology, Biomedical Research Center, Sir Runrun Shaw Hospital, Zhejiang University, Hangzhou, People's Republic of China.
authors.forename: Wenxia
authors.initials: W
authors.lastname: Xu
authors.affiliation: Department of Cell Biology, School of Basic Medical Sciences, Nanjing Medical University.
authors.forename: Pan
authors.initials: P
authors.lastname: Ni
authors.affiliation: Department of Molecular Cell Biology and Toxicology, School of Public Health, Nanjing Medical University.
authors.forename: Aiping
authors.initials: A
authors.lastname: Li
authors.affiliation: Department of Molecular Cell Biology and Toxicology, School of Public Health, Nanjing Medical University.
authors.forename: Jianwei
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Cell Biology, School of Basic Medical Sciences, Nanjing Medical University.
authors.forename: Shan
authors.initials: S
authors.lastname: Xu
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics; D015153:Blotting, Western; D002154:Calpain / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D002945:Cisplatin / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D006801:Humans; D020287:In Situ Nick-End Labeling; D035683:MicroRNAs / Q000235:genetics* / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism*
chemical_list: D020413:3' Untranslated Regions; C551410:MIRN491 microRNA, human; C561679:MIRN99 microRNA, human; D035683:MicroRNAs; D002154:Calpain; C527669:CAPNS1 protein, human; D002945:Cisplatin
keywords: CAPNS1; cisplatin resistance; gastric cancer.; miR-491; miR-99a