Effect of etoposide on grass pea DNA topoisomerase II: an in silico, in vivo, and in vitro assessments

Background Etoposide is one of the most potential anti-cancerous drugs that targets topoisomerase II (topoII) and inhibits its activity by ligation with the DNA molecule. Results In silico study confirmed that the etoposide-binding sites of topoII are conserved among the plants and human. The efficacy of the drug on plant system was initially assessed using germinated grass pea ( Lathyrus sativus L.) seedlings (in vivo) in relation to radicle length and mitotic index. The callus system (in vitro) was also used to elucidate the effect of etoposide on callus growth kinetics. Furthermore, it was observed that etoposide able to inhibit the division of polyploid cells induced by colchicine treatment (0.5%, 8 h). To determine the molecular interaction, topoII was isolated from young grass pea leaves using polyethylene glycol fractionation and ammonium sulphate precipitation followed by column chromatography on CM-Sephadex (C-25). The plasmid linearization assays by isolated plant topoII in the presence of etoposide significantly revealed the functional similarity of plants and human topoII. Results indicated that the effect of etoposide on plant topoII is significant. Conclusions This study may pave the way to develop a plant-based assay system for screening the topoisomerase targeted anti-cancerous drugs, as it is convenient and cost-effective.