MiR-509-3p is clinically significant and strongly attenuates cellular migration and multi-cellular spheroids in ovarian cancer

Yinghong Pan,Denise Brooks,Andrew J Mungall,Jinsong Liu,Cristian Coarfa,Amy C Rowat,Yussanne Ma,Richard A Moore,Sagar L Patil,Nina Thiessen,Alka Mansukhani,Yunfei Wen,Marco A Marra,Gordon Robertson,Andy Chu,Reanne Bowlby,Upal Basu-Roy,Xinna Zhang,Payal Sipahimalani,Chad V Pecot,Steven J.M Jones,Lykke Pedersen,Preethi H Gunaratne,Anil K Sood,Jacquie Schein ,Cy Chan ,Emilia L Lim ,Anadulce Hernández-Herrera

doi:10.18632/oncotarget.8412

Abstract

Ovarian cancer presents as an aggressive, advanced stage cancer with widespread metastases that depend primarily on multicellular spheroids in the peritoneal fluid. To identify new druggable pathways related to metastatic progression and spheroid formation, we integrated microRNA and mRNA sequencing data from 293 tumors from The Cancer Genome Atlas (TCGA) ovarian cancer cohort. We identified miR-509-3p as a clinically significant microRNA that is more abundant in patients with favorable survival in both the TCGA cohort (P = 2.3E–3), and, by in situ hybridization (ISH), in an independent cohort of 157 tumors (P < 1.0E–3). We found that miR-509-3p attenuated migration and disrupted multi-cellular spheroids in HEYA8, OVCAR8, SKOV3, OVCAR3, OVCAR4 and OVCAR5 cell lines. Consistent with disrupted spheroid formation, in TCGA data miR-509-3p's most strongly anti-correlated predicted targets were enriched in components of the extracellular matrix (ECM). We validated the Hippo pathway effector YAP1 as a direct miR-509-3p target. We showed that siRNA to YAP1 replicated 90% of miR-509-3p-mediated migration attenuation in OVCAR8, which contained high levels of YAP1 protein, but not in the other cell lines, in which levels of this protein were moderate to low. Our data suggest that the miR-509-3p/YAP1 axis may be a new druggable target in cancers with high YAP1, and we propose that therapeutically targeting the miR-509-3p/YAP1/ECM axis may disrupt early steps in multi-cellular spheroid formation, and so inhibit metastasis in epithelial ovarian cancer and potentially in other cancers.

Highlights

Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy, typically presenting as an aggressive, advanced stage cancer with widespread metastases in the peritoneum [1]
Our data suggest that the miR-5093p/YAP1 axis may be a new druggable target in cancers with high YAP1, and we propose that therapeutically targeting the miR-509-3p/YAP1/extracellular matrix (ECM) axis may disrupt early steps in multi-cellular spheroid formation, and so inhibit metastasis in epithelial ovarian cancer and potentially in other cancers
In the work reported here, we identified microRNA509-3p as a clinically significant microRNA by integrating functional assays and clinical outcomes with microRNA and RNA sequencing data from over 250 tumors from The Cancer Genome Atlas (TCGA) ovarian cancer cohort

Summary

Introduction

Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy, typically presenting as an aggressive, advanced stage cancer with widespread metastases in the peritoneum [1]. It metastasizes primarily by cells exfoliating into the peritoneal fluid, and aggregating into multicellular spheroids that invade the peritoneal membrane [2, 3] and can resist chemotherapy [4,5,6]. We report results from 293 TCGA ovarian tumors, using messenger RNA (mRNA) and microRNA (miRNA/miR) sequencing data. We anticipated that the sequencing data could yield new insights by offering a wider dynamic range than microarrays, higher spatial resolution and sensitivity, isoform-specific mRNA expression, and better discrimination between miRNA stem-loops and mature miRNA strands [9]

Methods

Results

Conclusion