Vol.5 No.3 – 7 : Downregulation of miR-23a and miR-24 in human hepatocellular carcinoma cells by Sorafenib via transforming growth factor beta 1 in a SMAD dependent manner

By: Eman G. Ayad¹, Mohga S. Abdulla*¹, Hayat M. Sharada¹, Abdel Hady A. Abdel Wahab^2, and Abeer M. Ashmawy².

¹Department of chemistry, Faculty of Science, Helwan University, Egypt.

² Departments of Cancer Biology, National Cancer Institute, Cairo University, Egypt.

Abstract

MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression through post-transcriptional interactions with mRNA. MiRNAs have recently considered as key regulators of various cancers including liver cancer. Sorafenib is one of antitumor drug for treatment of advanced hepatocellular carcinoma. It acts as a multikinase inhibitor suppressing cell proliferation and angiogenesis. This study try to investigate a potential microRNA-based mechanism of action of the drug,by studying the effect of sorafenib on miR-23a and miR-24 levels in HCC cell lines HepG2 /Huh7 and revealing the possible drug mechanism against these oncogenic mi-RNAS,in this study cell viability of cultured HepG2 /Huh7 after treatment with sorafenib were evaluated using Sulphorhodamine-B (SRB) assay, cell cycle and apoptosis estimated by flowcytometry assay. Caspase-3 level was determined using ELISA assay. Moreover, MiR-23a and miR-24 expressions levels analyzed by qPCR. Finally, TGF-β levels and phosorylated smad2, 3 were examined after treatment with sorafenib using ELISA and western blotting. Our data confirmed the Sorafenib inhibition of cell growth in both cell lines which was accompanied by significantly increased in cell apoptosis and cell cycle arrest. Cells treated with sorafenib showed a significant decrease in miR-23a and miR-24 levels in both cell lines. Interestingly,   the change in these oncogenic miRNA was accompanying with a significant decrease of (TGF-β1) and phosorylated smad2, 3 proteins levels. Our study suggested that inhibition of tgf beta pathway in smad dependent manner could be the way characteristic of sorafenib to inhibit the oncogenic miR-23a and miR-24 levels in HCC.  

Downregulation of miR-23a and miR-24 in human hepatocellular carcinoma cells by Sorafenib via transforming growth factor beta 1 in a SMAD dependent manner

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