Impact of circulating microRNA on chemoresistance in patients with esophageal cancer

2013 Fiscal Year Final Research Report

• Project/Area Number: 24791416
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Digestive surgery
• Research Institution: Osaka University
• Principal Investigator: TANAKA Koji 大阪大学, 医学部附属病院, 医員 (70621019)
• Project Period (FY): 2012-04-01 – 2014-03-31
• Keywords: 食道癌 / microRNA / 抗癌剤耐性

Research Abstract

Serum expression of miRNAs selected by miRNA array was measured by quantitative RT-PCR in 68 patients with esophageal cancer who received cisplatin-based chemotherapy to examine the relationship between miRNA expression and response to chemotherapy. In vitro assays were conducted using esophageal cancer cells and normal fibroblasts (NOF) to investigate the mechanism of miRNA-induced chemoresistance. 18 miRNAs were different between responders and non-responders by miRNA array. Of these, high expression levels of miR-X correlated with poor response to chemotherapy. Although transfection of miR-X to cancer cells had no significant impact on chemosensitivity, esophageal cancer cells cultured in supernatant of miR-X-transfected NOF showed reduced chemosensitivity. miR-X-transfected NOF showed a-SMA expression. Our results indicated that miR-X is involved in resistance to chemotherapy in esophageal cancer, through transformation of NOF into cancer-associated fibroblasts.