Supplementary Fig. S7. A. Principal component analysis (PCA), and B. Hierarchical Clustering (HCL) Analysis showing distinct difference between transcript profile of siCtrl- and siHuR-transfected A2780 cells. C and D. MA plots of gene expression of 163 genes following transfection of A2780 cells with siHuR and with siCtrl. C. 66 genes were significantly down-regulated and 50 genes were significantly up-regulated when HuR was knocked down. D. 37 significantly down-regulated genes (56%) are direct HuR targets (i.e., HuR binds to their mRNA transcript); 31 significantly up-regulated genes (62%) are direct HuR targets.
Funding
Marsha Rivkin Center for Ovarian Cancer Research
Sharpe-Strumia Research Foundation of the Bryn Mawr Hospital
Sarah Parvin Foundation
ARTICLE ABSTRACT
Growing evidence shows that cancer cells use mRNA-binding proteins and miRNAs to posttranscriptionally regulate signaling pathways to adapt to harsh tumor microenvironments. In ovarian cancer, cytoplasmic accumulation of mRNA-binding protein HuR (ELAVL1) is associated with poor prognosis. In this study, we observed high HuR expression in ovarian cancer cells compared with ovarian primary cells, providing a rationale for targeting HuR. RNAi-mediated silencing of HuR in ovarian cancer cells significantly decreased cell proliferation and anchorage-independent growth, and impaired migration and invasion. In addition, HuR-depleted human ovarian xenografts were smaller than control tumors. A biodistribution study showed effective tumor-targeting by a novel Cy3-labeled folic acid (FA)-derivatized DNA dendrimer nanocarrier (3DNA). We combined siRNAs against HuR with FA-3DNA and found that systemic administration of the resultant FA-3DNA-siHuR conjugates to ovarian tumor–bearing mice suppressed tumor growth and ascites development, significantly prolonging lifespan. NanoString gene expression analysis identified multiple HuR-regulated genes that function in many essential cellular and molecular pathways, an attractive feature of candidate therapeutic targets. Taken together, these results are the first to demonstrate the versatility of the 3DNA nanocarrier for in vivo–targeted delivery of a cancer therapeutic and support further preclinical investigation of this system adapted to siHuR-targeted therapy for ovarian cancer. Cancer Res; 76(6); 1549–59. ©2016 AACR.
