Negative correlation of ITCH E3 ubiquitin ligase and miRNA-106b dictates metastatic progression in pancreatic cancer

Abstract

// Zhu-lin Luo 1, * , Hui-jun Luo 2, * , Chen Fang 3, * , Long Cheng 1, * , Zhu Huang 1 , Ruiwu Dai 1 , Kun Li 4 , Fu-zhou Tian 1 , Tao Wang 1 , Li-jun Tang 1 1 Department of General Surgery, Chengdu Military General Hospital, Chengdu, Sichuan 610083, P. R. China 2 Department of Biochemistry and Molecular Biology, Mayo Clinic Arizona, Scottsdale, AZ 85259, USA 3 Chengdu Military Institute for Drug and Instrument Control, Chengdu, Sichuan 610020, P. R. China 4 Medical Central Laboratory, Chengdu Military General Hospital, Chengdu, Sichuan 610083, P. R. China * These authors contributed equally to this work Correspondence to: Li-jun Tang, e-mail: lijuntang_med@126.com Tao Wang, e-mail: taowang_med@126.com Keywords: ITCH, miR-106b, pancreatic cancer, YAP, metastasis Received: April 24, 2015      Accepted: November 14, 2015      Published: November 26, 2015 ABSTRACT Pancreatic cancer is one of the major malignancies and cause for mortality across the world, with recurrence and metastatic progression remaining the single largest cause of pancreatic cancer mortality. Hence it is imperative to develop novel biomarkers of pancreatic cancer prognosis. The E3 ubiquitin ligase ITCH has been previously reported to inhibit the tumor suppressive Hippo signaling by suppressing LATS1/2 in breast cancer and chronic lymphocytic leukemia. However, the role of ITCH in pancreatic cancer progression has not been described. Here we report that ITCH transcript and protein expression mimic metastatic trait in pancreatic cancer patients and cell lines. Loss-of-function studies of ITCH showed that the gene product is responsible for inducing metastasis in vivo . We furthermore show that hsa-miR-106b , which itself is down regulated in metastatic pancreatic cancer, directly interacts and inhibit ITCH expression. ITCH and hsa-miR-106b are thus potential biomarkers for pancreatic cancer prognosis.