Cytotoxic effect of partially purified conotoxin from Conus virgo on Human Colon Cancer cell line HT-29

Abstract

The present study focused on partial purification of conotoxin from the crude venom of Conus virgo and tested for its anticancer potential against human colon cancer cell line HT-29. The screening of crude venom was carried out using human cancer cell lines such as MCF-7 and HT-29 by MTT method. The result showed IC50 for HT-29 at 40 μg/ml for 24 h. incubation whereas MCF-7 cell line failed to show the decreased cell viability (71% cell viability at a maximum concentration of 140 μg/ml). The conotoxin was purified using DEAE-cellulose column chromatography; purified fraction-1 exhibited significantly decreased cell viability at 20, 40, 60, 80, 100, 120 and 140 ng/ml concentrations in HT-29cells and IC50 was found at 120 ng/ml for 24h. incubation. In Cytomorphological observation, distinct cellular changes such as cell shrinkage, loss of adherence and loss of colony formation were observed. The nuclear morphological damages were observed in propidium iodide staining. DNA fragmentation was observed in the treatment of fraction-1 on HT-29 cells when compared to control cells using agarose gel electrophoresis. Based on these findings, the fraction 1 conotoxin induced the nuclear damage and caused cell death in HT-29 cells, so it could be a good candidate for colon cancer chemotherapy.