Cytotoxic and apoptotic effects of chemically synthesized silver nanoparticles loaded with recombinant Staphylococcus LukS-PV toxin.

Chronic myeloid leukemia (CML) accounts for approximately 15% of leukemias. LukS-PV, a Panton-Valentine leucocidin (PVL) component, is secreted by Staphylococcus aureus. Silver nanoparticles have increasingly been used for different purposes, most notably for drug delivery and anticancer agents. In this work, the cytotoxicity effect of recombinant LukS-PV protein, chemically synthesized AgNPs, and recombinant LukS-PV protein-loaded silver nanoparticles was investigated on human Chronic myeloid leukemia K562 cells and human normal embryonic kidney HEK293 cells. Cell apoptosis was investigated by staining with Annexin V/propidium iodide. The recombinant LukS-PV protein-loaded silver nanoparticles exhibited dose-dependent cytotoxicity and induced apoptosis in the K562 cells but had little effect on normal HEK293 cells. After 24 h of exposure to recombinant LukS-PV protein-loaded silver nanoparticles (IC50 concentration), flow cytometry showed that 31.17% of K562 cells were apoptotic. These results indicate that recombinant LukS-PV protein-loaded silver nanoparticles maybe are a potential chemotherapeutic agent candidate against K562 cells. Hence, silver nanoparticles could be used as drug carriers for toxin release to cancer cells.

The anticancer effect of recombinant LukS-PV protein and silver nanoparticles loaded with this protein.

LukS-PV is a component of Panton-Valentine leucocidin (PVL) and is secreted by Staphylococcus aureus. Silver nanoparticles exhibit considerable potential as anticancer agents and drug delivery systems. Drug delivery is a way to deliver medicinal combinations to achieve a beneficial therapeutic effect. In the current study, recombinant LukS-PV protein-loaded silver nanoparticles were prepared and their cytotoxicity effect was analyzed on human breast cancer cells and human normal embryonic kidneys cells by MTT assay. Apoptosis was investigated by staining with Annexin V/propidium iodide. The recombinant LukS-PV protein-loaded silver nanoparticles showed dose-dependent cytotoxicity and induced apoptosis in the MCF7 cells and had a lesser effect on HEK293 cells. After 24 h exposure to the recombinant LukS-PV protein-loaded silver nanoparticles (IC50), Annexin V-FITC/PI FCM revealed that 33.2% of MCF7 cells were apoptotic. In conclusion, recombinant LukS-PV protein-loaded silver nanoparticles probably cannot be a better alternative for the targeted healing approaches to cancer therapies. Hence, it is suggested that silver nanoparticles could be utilized as a delivery system for releasing toxins into cancer cells.

Expression and prognostic significance of bcl-2 and bax in the progression and clinical outcome of transitional bladder cell carcinoma.

OBJECTIVE: To evaluate the mRNA expression ratio of Bcl-2/Bax both in normal and tumoral bladder tissues of patients with transitional cell carcinoma (TCC) of bladder and investigate potential correlation between this expression ratio and clinical outcome. MATERIALS AND METHODS: In this experimental study, we used real time-PCR to investigate the expression of Bcl-2 and Bax both in normal and tumoral bladder tissues. The Bcl-2/ Bax expression ratio was determined in tumoral bladder tissues of patients with transitional cell carcinoma of the bladder (n=40) and correlation between expression ratios and the emergence of early relapses in a follow-up of 14-30 months was examined. RESULTS: Relapse-free time in 14/31 patients (45.16%) with Bcl-2/Bax>1 was shorter than 9 months (range of 2-9 months) with 5.7 months average median while 17/31 patients (54.84%) with Bcl-2/Bax<1 are currently relapse-free (14-30 months). Bcl-2 and Bax expression levels were not solely correlated with clinical outcome and progression of carcinogenesis. CONCLUSION: The mRNA expression ratio of Bcl-2/Bax in tumoral bladder tissues may serve as a significant prognostic indicator in predicting the clinical outcome in low grade non-invasive bladder cancer.