Anticancer activity of cucurbitacin-A in ovarian cancer cell line SKOV3 involves cell cycle arrest, apoptosis and inhibition of mTOR/PI3K/Akt signaling pathway

Abstract

Purpose: Ovarian cancer is one of the deadly causes of gynecological cancer related mortality worldwide. Despite initial responses to chemotherapy, the disease consistently relapses. Therefore there is an urgent need for identification of anticancer lead molecules for treatment and management of ovarian cancer. The present study evaluated the anticancer activity of cucurbitacin-A on ovarian SKVO3 cancer cells.

Methods: The cell viability of SKVO3 cells was evaluated by MTT assay, while clonogenic assay was used to evaluate the effects on cancer cell colony formation. DAPI staining using fluorescence microscopy was used to evaluate the effects of the compound on apoptosis. Flow cytometry was used to study the effects on cell cycle phase distribution, reactive oxygen species (ROS) generation and mitochondrial membrane potential (MMP) loss.

Results: Cucurbitacin-A exhibited an IC50 of 40 μM against ovarian SKVO3 cancer cell line. It also caused DNA damage in SKVO3 cells and also prompted ROS mediated alterations in MMP. On the other hand, it triggered cell cycle arrest of SKVO3 at G2/M checkpoint. The activation of the PI3K/AKT/mTOR pathway plays a vital role in ovarian cancer tumorigenesis, progression and chemotherapy resistance. The results showed that cucurbitacin-A considerably inhibited the expression levels of key proteins of PI3K/Akt/ mTOR signaling pathway.

Conclusion: The study showed that cucurbitacin-A is a potent agent against ovarian cancer cells, can be considered for further in vivo research and can also be developed as a possible lead molecule.