Mechanism of anti-cancer activity of andrographolide and DRF 3188 – In vitro studies: Cell cycle analysis A. Fluorescence associated cell sorting analysis of MCF 7 cells treated with andrographolide (5 μM) or DRF 3188 (5 μM) for a period of 24 hours. Lovastatin (10 μM) and Butyrolactone (10 μM) were used as positive controls. Andrographolide and DRF 3188 exhibit a G0-G1 arrest like Lovastatin. Butyrolactone treated MCF 7 cells exhibit a G2-M arrest. B. After a 48 h treatment with Andrographolide or DRF 3188 MCF7 cells exhibit a G0-G1 arrest, similar to Lovastatin. Butyrolactone treated cells exhibit a G2-M arrest.