Altered Long Non-coding RNAs Expression and Cytotoxic and Anti-proliferative Activity of Dendrosomal Nano-curcumin in Ovarian Cancer Cells

Background: Curcumin is a polyphenol derived from the rhizome of turmeric, which has significant chemoprevention and chemotherapeutic effects. Long non-coding RNAs (lncRNAs) are longer than 200 nucleotides and play a crucial role in various biological processes. Since aberrant lncRNAs expression affects the development and progression of tumors, the present study was conducted to determine the cytotoxic potential of dendrosomal nano-curcumin (DNC) against ovarian cancer cell proliferation and apoptosis and altered expression of some lncRNAs involved in ovarian cancer. Methods: In vitro cytotoxic activity of DNC against OVCAR3 and SKOV3 human ovarian cancer cells and HFSF-PI3 human fibroblasts cells as a control was evaluated by MTT assay. Real-time PCR and western blot methods were used to determine the apoptosis-inducing effect of DNC through analyzing apoptosis marker genes and protein expression, respectively. We also checked the ovarian cancer cells apoptosis induced with change in expression levels of some lncRNAs. Results: Our results revealed that DNC significantly decreased viability of ovarian cancer cells as compared to Cur. Moreover, DNC reduced the relative expression levels of HOTAIR and H19 and increased the expression of MEG3. Bcl2 expression was down-regulated in mRNA and protein level after DNC treatment, whereas knockdown of MEG3 reduced it. Conclusions: Our findings discovered the effect of DNC on growth inhibition as well as modulation of some lncRNAs in ovarian cancer cells. We also observed that MEG3 down-regulation can suppress the effect of DNC on down-regulation of Bcl-2 as an anti-apoptotic protein. This may suggest the role of MEG3 in DNC-induced apoptosis.