Integrin-Linked Kinase Is a Novel Therapeutic Target in Ovarian Cancer.

Michael A Ulm,Suriyan Ponnusamy,Adam C Elnaggar,Patrick W Blackburn,Ramesh Narayanan,Ben R Wilson,Sarah Asemota,Yinan Wang,Tiffany M Redfern

doi:10.3390/jpm10040246

Abstract

Objective: The objective of this study is to identify and validate novel therapeutic target(s) in ovarian cancer. Background: Development of targeted therapeutics in ovarian cancer has been limited by molecular heterogeneity. Although gene expression datasets are available, most of them lack appropriate pair-matched controls to define the alterations that result in the transformation of normal ovarian cells to cancerous cells. Methods: We used microarray to compare the gene expression of treatment-naïve ovarian cancer tissue samples to pair-matched normal adjacent ovarian tissue from 24 patients. Ingenuity Pathway Analysis (IPA) was used to identify target pathways for further analysis. Integrin-linked kinase (ILK) expression in SKOV3 and OV90 cells was determined using Western blot. ILK was knocked down using CRISPR/Cas9 constructs. Subcutaneous xenograft study to determine the effect of ILK knockdown on tumor growth was performed in NOD SCID gamma mice. Results: Significant upregulation of the ILK pathway was identified in 22 of the 24 cancer specimens, identifying it as a potential player that could contribute to the transformation of normal ovarian cells to cancerous cells. Knockdown of ILK in SKOV3 cells resulted in decreased cell proliferation and tumor growth, and inhibition of downstream kinase, AKT (protein kinase B). These results were further validated using an ILK-1 chemical inhibitor, compound 22. Conclusion: Our initial findings validate ILK as a potential therapeutic target for molecular inhibition in ovarian cancer, which warrants further investigation.

Highlights

A hallmark of ovarian cancer is the aggressive and silent nature of metastasis, predominantly through direct extension, into the peritoneal cavity [1]
Downregulation of Integrin-linked kinase (ILK) using sgRNA resulted in reduced cell proliferation and tumor growth, confirming ILK as a valid therapeutic target
AFoRrPpiaitniecnretsawseidthsouurtvival outcosmomesatfiocrorpgaetiremnltinsewhiothmoblootghousos mrecaotmicbainnadtigoenrmmulitnateiomnsuatnadtiofonrsthinosBeRwChAoseancadncgeernheasveenbceocodmineg the proterinessisitnavntoltvoePdAiRnPDi tNheArarpeyp, aaidrvbaynchesominotlaorgeotueds rtehceorampebuintiacstioarne. nFeoedrepdatoieinmtsprwovitehsouurtvisvoaml oaftic or germline homologous recombination mutations and for those whose cancer have become resistant to PARPi therapy, advances in targeted therapeutics are needed to improve survival of patients with advanced ovarian cancer [26]

Summary

Introduction

A hallmark of ovarian cancer is the aggressive and silent nature of metastasis, predominantly through direct extension, into the peritoneal cavity [1]. Metastases are most commonly found within the omentum, the peritoneum, the diaphragm, and bowel surfaces [1,2] This intraperitoneal dissemination requires detachment, or exfoliation, from the primary tumor on the ovary or fallopian tube [1]. This disruption of integrin–extracellular matrix interactions in normal epithelial cells induces apoptosis [3]. Several genome-wide expression studies have been conducted in epithelial ovarian cancer to determine the mechanism for the aggressive phenotype and to identify therapeutic targets [4,5,6]. Downregulation of ILK using sgRNA resulted in reduced cell proliferation and tumor growth, confirming ILK as a valid therapeutic target

Materials and Methods

Findings

Discussion