Bostrycin inhibits proliferation of human lung carcinoma A549 cells via downregulation of the PI3K/Akt pathway

We used MTT assay, flow cytometry, microarray, real time PCR, and Western blotting to detect the effect of bostrycin on A549 human pulmonary adenocarcinoma cells.We showed a significant inhibition of cell proliferation and induction of apoptosis in bostrycin-treated lung adenocarcinoma cells. Bostrycin treatment caused cell cycle arrest in the G0/G1 phase. We also found the upregulation of microRNA-638 and microRNA-923 in bostrycin-treated cells. further, we found the downregulation of p110α and p-Akt/PKB proteins and increased activity of p27 protein after bostrycin treatment in A549 cells.Our study indicated that bostrycin had a significant inhibitory effect on proliferation of A549 cells. It is possible that upregulation of microRNA-638 and microRNA-923 and downregulaton of the PI3K/AKT pathway proteins played a role in induction of cell cycle arrest and apoptosis in bostrycin-treated cells.Lung cancer is the most common type of cancer worldwide. Despite recent advances in surgical techniques and chemotherapy/radiotherapy strategies, the long-term survival rates remain poor. There is therefore an urgent need to develop new therapeutic strategies in order to significantly improve the prognosis in lung cancer patients. Growth factor signaling pathways have been shown to be important targets in lung cancer therapy. Targeting such intracellular pathways that regulate proliferation, apoptosis, metastasis and resistance to chemotherapy represents an important therapeutic strategy for lung cancer [1].Marine microorganisms can grow under adverse conditions such as low temperatures, high pressures, and poor nutrition. The diversity of biological activities in these environments exceeds those of land organisms. Some metabolites from these marine microorganisms have novel structures and biological activities including anticancer, antiviral and immune enhancement properties. A recent study on marine pharmacology coordinated by multiple countries demonstrated antitumor activi