Cucurbitacin B inhibits proliferation and induces apoptosis via STAT3 pathway inhibition in A549 lung cancer cells

Natural products are a great source of Cancer chemotherapeutic agents. The present study was conducted to investigate whether cucurbitacin B (CuB), one of the most potent and widely used cucurbitacins, inhibits proliferation and induces Apoptosis in the A549 lung Cancer cell line. Furthermore, CuB induced Apoptosis of A549 cells in a -concentration-dependent manner, as determined by fluorescence microscopy, flow cytometry and transmission electron microscopy. The present study also demonstrated that CuB dose-dependently inhibited lung Cancer cell proliferation, with cell cycle inhibition and cyclin B1 downregulation. Apoptosis induced by CuB was shown to be associated with cytochrome c release, B-cell lymphoma 2 downregulation and signal transducer and activator of transcription 3 pathway inhibition. CuB may prove to be a useful approach for the chemotherapy of lung Cancer.