MicroRNA-145 enhances lung cancer cell progression after exposure to lyophilized fertile hydatid cyst fluid of Echinococcus granulosus sensu stricto

Abstract

There is increasing evidence that the secretory/excretory antigens of the larval stage of Echinococcus granulosus can induce both anticancer and oncogenic effects between parasite-derived metabolites and various cancer cells. The dual role of miR-145 as either a tumor suppressor or oncogene has already been reported in cancer. However, the mechanism by which miR-145 induces apoptosis in lung cancer cells treated with hydatid cyst fluid (HCF) remains unclear. The fertile HCF was obtained from sheep, purified and lyophilized. H1299 human lung cancer cells were then cultured into two groups: HCF-treated H1299 lung cancer cells and untreated H1299 cancer cells as control cells. Cell viability was assessed using MTT assay to evaluate the effects of HCF on the H1299 cells. Caspase-3 activity was assessed by fluorometric assay. In addition, mRNA expression levels of VGEF, vimentin, caspase-3, miRNA-145, Bax and Bcl-2 genes were quantified by real-time PCR. A scratch test was also performed to assess the effects of HCF on cell migration. The MTT assay revealed that the growth of H1299 cells increased when treated with 60 μg/mL of fertile HCF for 24 h. The fold change of caspase-3, miRNA-145, Bax/Bcl-2 ratio and caspase-3 activity was lower in HCF-treated H1299 cells compared to the control cell. The fold change in VGEF and vimentin gene expression was higher in the HCF-treated H1299 cells than in the control cell. The scratch test results showed that H1299 cell mobility increased 24 and 48 h after exposure to HCF. Our results suggest that the downregulation of miR-145 in HCF-treated H1299 cells may play a role as a possible oncogenic regulator of lung cancer growth. To confirm this assumption, further studies are required to evaluate the microRNA profile and effective oncogenes in vivo.