Journal of Clinical and Biomedical Sciences
DOI: 10.58739/jcbs/v15i4.25.139
Year: 2025, Volume: 15, Issue: 4, Pages: 277- 283
Original Article
Seyedeh Maryam Mousavi1*, Soroush Karimi2, Atefeh Azadi3, Mahsa Boogari4, Hossein Joveini5, Arman Izadian6
1Department of Biology, Faculty of Sciences, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
2Nano Drug Delivery Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran.
3Department of Laboratory Sciences, Faculty of Paramedicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
4Department of Molecular Medicine, Pasteur Institute of Iran, Tehran, Iran.
5Department of Laboratory Sciences, Faculty of Medical Sciences, Islamic Azad University, Gorgan Branch, Gorgan, Iran.
6Department of Vector Biology and Control of Diseases, School of Public Health,Tehran University of Medical Sciences, Tehran, Iran.
*Corresponding Author
Email: [email protected]
Received Date:24 March 2025, Accepted Date:29 July 2025, Published Date:31 December 2025
A protein called cytolysin A or ClyA, encoded by certain bacteria species, can cause cytotoxicity. Although the ClyA protein is not typically expressed at detectable levels in most E. coli strains, here it was successfully overproduced and purified by cloning the structural gene into a hns mutant strain. The cytotoxicity of the purified cytolysin was assessed on two MCF-7 cancer cell lines and HDF normal cell line using the MTT assay. Flow cytometry was employed to examine the cytolysin's ability to induce apoptosis in cancer cells. In addition, a Western blot analysis was carried out to evaluate the expression levels of P53, Bcl2, and Bax proteins. The results revealed that cytolysin exhibited dose-dependent and time-dependent toxicity towards cancer cells, while showing minimal toxicity against normal cells, indicating its selective action against cancer cells. Cytolysin had an IC50 value of 3.29 µg/ml against MCF-7 cancer cells and 12.6 µg/ml against HDF normal cells. Flow cytometry results further demonstrated that cytolysin induced apoptosis in cancer cells, evidenced by increased expression of p53 and BCL2, as well as decreased in Bax, in gene and protein levels. These findings underscore the potential of cytolysin as a targeted therapy for cancer, highlighting its selective cytotoxic effect on cancer cells.
Keywords: Cytolysin-A, Breast cancer, Cytotoxicity, Flowcytometry, Western blotting
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Published By Sri Devaraj Urs Academy of Higher Education, Kolar, Karnataka
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