doi:10.1038/nindia.2016.77 Published online 13 June 2016
A small herb belonging to the castor (Euphorbiaceae) family growing in the waste lands of southern India has shown promise in killing cancer cells without affecting healthy cells under laboratory conditions, according to new research1.
In lab experiments at the Sri Ramachandra University (SRU) in Chennai, researchers have shown that acetone extract (AcE) of Croton bonplandianus, known in Hindi as ‘Ban tulsi’ or ‘jungle tulsi’ due to the resemblance of its leaves to that of tulsi (basil), is able to kill lung cancer cells without affecting normal cells. The plant is traditionally used both as a fuel and a detergent.
Cancer has been associated with increased levels of intra-cellular free radicals. Therefore, scavenging these radicals with antioxidant supplement is considered a way to arrest the progression of cancer. The SRU study was prompted by the preliminary phytochemical screening that confirmed the presence of potent free radical scavenging alkaloids, carbohydrates, flavonoids, phenols, tannins, saponins and terpenoids in the C. bonplandianus leaf extract. Encouraged by this finding, the researchers investigated the antioxidant and cytotoxic effects of the extract on Lung adenocarcinoma cell line (A549) they obtained from the National Centre for Cell Sciences, Pune.
Acetone leaf extract of C. bonplandianus showed cytotoxicity and cell proliferation inhibition in A549 cells "in a dose-dependent manner without affecting the normal cells." The cancer cells were more sensitive to the leaf extract "compared to the standard drug (cisplatin)," they report.
Using flow cytometry, they found that cell death (apoptosis) was induced at the so called G2M phase of the cell cycle (when the cell nucleus starts to divide) confirming that the leaf extract induces cell cycle arrest as well as cell death.
The results suggest that C. bonplandianus could serve as a potential source of alternative therapeutic agent for treating cancer, according to the researchers. Further research is required to isolate the active principle compound and determine its anticancer property, they say.