Abstract 4491: Antiproliferative activity of bacterial proteins against MDA-MB-231 human breast adenocarcinoma and HEPG-2 human hepatocellular carcinoma cells
Authors: Sharma Asvene K. , Roy Partha , Vats Pratibha 
Published: August 2015

Background:

Cancer remains one of the most dangerous human diseases. According to International Agency for Research on Cancer (IARC) (WHO) Global burden rises to 14.1 million new cases and 8.2 million cancer deaths in 2012 and nearly 13.3 million people are likely to die annually of cancer by 2030. Further due to ever emerging drug resistance in cancers and increasing number of cancer deaths there is a need to recognize new therapeutic molecules against the cancer cells. Bacterial strains have been shown to possess anticancer potential in the past few years. Bacterial proteins from strains Lactobacillus sps, Bacillus cereus, Serratia marcence and Shigella flexneri have been tested for anticancer activity.

Methods

Protein extracts of Lactobacillus sps (MTCC 4184, 9496, and 10093), Bacillus cereus (MTCC 7166, 9017 and 10202), Serratia marcence (MTCC 7641, 7298 and 7729), Shigella flexneri (MTCC 1457 and 9543) were evaluated for their anticancer potential against human cancer cell lines Breast Cancer (MDA-MB-231) and Hep-G2 (Liver Cancer). Inhibition of Cancer Cells proliferation was confirmed by MTT Cell Viability Assay, Fluorescent Staining, Caspase-3 activity by Western blotting, DNA Fragmentation and Flow Cytometery. Chromatography and electrophoresis techniques were used for protein fractionation and analysis.

Results

In general, most of the bacterial protein extracts were found to be effective against one or more cancer cell lines. Protein extract of Lactobacillus sps (MTCC 4184), Bacillus cereus (MTCC 10202) and Shigella flexneri (MTCC 9543) inhibited both the cancer cell lines. Lactobacillus sps (MTCC 9496) was effective only against MDA-MB-231. Serratia marcence (MTCC 7298 and 7729) protein extract inhibited growth MDA-MB-231, while no effect on HepG2 was observed. Bacillus cereus (MTCC 7166) inhibited MDA-MB-231 and not HepG2. Protein extract of Lactobacillus sps (MTCC 10093), Bacillus cereus (MTCC 2763), Serratia marcence (MTCC 7641) and Shigella flexneri (MTCC1457) were none effective to both the cell lines. The cancer cell mortality was observed from 52% to 71% + 2%. Fluorescent staining and increased Caspase-3 activity confirmed by western blotting, DNA fragmentation and detection of cell cycle arrest by Flow Cytometry suggested that apoptosis was the major mechanism in inhibition of MDA-MB-231 and Hep-G2 cancer cells. Further, protein purification and analysis suggest that these are the low molecular mass bacterial protein which potentially inhibit cancer cell proliferation and act as anticancer molecules. The study confirms the anticancer potential of bacterial proteins which may constitute valuable candidates for development of novel anticancer drugs.

Conclusion

The study confirms the anticancer potential of bacterial proteins which may constitute valuable candidates for designing and development of novel anticancer drugs.

Citation Format: Asvene K. Sharma, Partha Roy, Pratibha Vats. Antiproliferative activity of bacterial proteins against MDA-MB-231 human breast adenocarcinoma and HEPG-2 human hepatocellular carcinoma cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4491. doi:10.1158/1538-7445.AM2015-4491