Abstract

ANTI-NEOPLASTIC EFFECT OF OCIMUM SANCTUM METHANOL EXTRACT ON COLORECTAL CARCINOMA, GASTRIC CARCINOMA, HEPATOCELLULAR CARCINOMA & NORMAL CELLS

Gaurav Arya, Nilanjana Deb, Piyali Das, Vishal Sharma, Kanika Kisku and Shila Elizabeth Besra*

Abstract

The plant Ocimum sanctum (Holy Basil) is widely used in Indian traditional medicine as a broad spectrum medicine. This encouraged us to investigate the anti-cancer effect of the leaf of Ocimum sanctum in colorectal, gastric and hepatocellular carcinoma cell lines and delineate the apoptotic pathways. The cell cytotoxicity assay by MTT helped to evaluate the cytotoxic potential of the methanol extract Ocimum sanctum (OSME). To examine whether cell death occurred via apoptosis or necrosis, Annexin-V FITC double staining was done. Cell morphology and fragmented DNA was determined by fluorescence microscope and gel electrophoresis. The mitochondrial membrane potential assay was also performed by JC-1 staining. Cell cycle study helped to establish the phase distribution of the carcinoma as well as normal cells. OSME significantly inhibited the cell viability in a time and concentration dependent manner in all the carcinoma cells but in normal cells insignificantly inhibited. After treatment with the extract, hepatocarcinoma cells, showed several signs of apoptosis like chromatin condensation, nuclear fragmentation and formation of apoptotic bodies than control cells and degraded DNA bands in cancer cells. The flow cytometric analysis confirmed the presence of apoptotic cells in the early and late apoptotic stages whereas in normal cells apoptosis was not triggered. Cell cycle phase arrest was observed in the G0/G1 phase in only colorectal and hepatoma cancer cells. MMP shift assay exhibited significant change in the OSME treated cells only in colorectal and hepatocellular carcinoma cells. These finding suggest that methanol extract Ocimum sanctum (OSME) possesses anti-neoplastic effects via apoptosis not necrosis without toxicity. Further mechanistic studies are going on to determine the different pathways contributing to apoptosis.

Keywords: Ocimum sanctum, Colon, Hepatocellular, Carcinoma, Apoptosis.