Down-regulation of lncRNA, GAS5 decreases chemotherapeutic effect of dendrosomal curcumin (DNC) in breast cancer cells

Abstract

Background: Despite positive results obtained from anticancer activities of curcumin, there are some obstacles that limit its use as an anticancer agent.

Hypothesis/purpose: Different methods such as employing the dendrosomal curcumin (DNC) were examined to overcome such problems. There is increasing evidence representing long non-coding RNAs play important roles in biological processes. In this study, we focused on the roles of GAS5 in the anti-cancer effects of DNC on breast cancer.

Methods: We used several methods including MTT assay, apoptosis assay, cell cycle analysis, transwell migration assay and RT-PCR.

Results: We observed a significant increase in the expression of Tusc7, and GAS5 genes with DNC treatment of MCF7, MDA-MB231, and SKBR3 cells. Also, the combination of GAS5 down-regulation and DNC treatment showed lower percentages of apoptotic cells and a higher level of penetration through the membrane compared with DNC treatment alone. Furthermore, DNC induced a significant increase in the number of cells in sub G1/G1 phase and a decrease in the G2/M phase of the cell cycle. But, after GAS5 down-regulation alone opposite results was observed compared to DNC.

Conclusion: We observed that GAS5 down-regulation can suppress many aspects of DNC anti-cancer effects in breast cancer cells, it seems that co-treatment with DNC and GAS5 over-expression may provide a clinically useful tool for drug-resistance breast cancer cells.

Keywords: Breast cancer; Cell cycle; Cell proliferation; Curcumin; Dendrosomal curcumin; GAS5.