MATERIALS AND METHODS: Cell viability assay using MTT, DNA fragmentation assay and real-time PCR were used to evaluate the cytotoxic effects of latex whole C-serum and its subfractions on the cell lines.
RESULTS: MTT assay revealed very low LC(50) values, 2.0 and 280 ng/ml, for DCS and DCP treatments, respectively. DCS was proven to be more potent compared to DCP, in conferring specific anti-proliferative effects on the cancer cell lines. The study also indicated that anti-proliferative activity of pre-heated C-serum fractions diminished significantly.
CONCLUSION: Although noteworthy cell death was reported, DNA fragmentation assay and real-time PCR confirmed that that induced by latex C-serum subfractions was not promoted via the classical apoptotic signalling pathway.
METHODS: Transfection of ANXA1 siRNA was conducted to downregulate ANXA1 expression in Jurkat, K562 and U937 cells. Apoptosis and cell cycle assays were conducted using flow cytometry. Western blot was performed to evaluate ANXA1, caspases and Bcl-2 proteins expression. Phagocytosis was determined using hematoxylin and eosin staining.
RESULTS: The expression of ANXA1 after the knockdown was significantly downregulated in all cell lines. Genistein significantly induced apoptosis associated with an upregulation of procaspase-3, -9, and - 1 in Jurkat cells. The Bcl-2 expression showed no significant difference in Jurkat, K562 and U937 cells. Treatment with phytoestrogens increased procaspase-1 expression in Jurkat and U937 cells while no changes were detected in K562 cells. Flow cytometry analysis demonstrated that after ANXA1 knockdown, coumestrol and genistein caused cell cycle arrest at G2/M phase in selected type of cells. The percentage of phagocytosis and phagocytosis index increased after the treatment with phytoestrogens in all cell lines.
CONCLUSION: Phytoestrogens induced cell death in ANXA1-knockdown leukemia cells, mediated by Annexin A1 proteins. Graphical abstract.
Materials and methods: In the present study, we evaluated the in vitro cytotoxicity of double and triple combinations consisting of 1'S-1'-acetoxychavicol acetate (ACA), Mycobacterium indicus pranii (MIP) and cisplatin (CDDP) against 14 various human cancer cell lines to address the need for more effective therapy. Our data show synergistic effects in MCF-7 cells treated with MIP:ACA, MIP:CDDP and MIP:ACA:CDDP combinations. The type of interaction between MIP, ACA and CDDP was evaluated based on combination index being <0.8 for synergistic effect. Identifying the mechanism of cell death based on previous studies involved intrinsic apoptosis and nuclear factor kappa B (NF-κB) and tested in Western blot analysis. Inactivation of NF-κB was confirmed by p65 and IκBα, while intrinsic apoptosis pathway activation was confirmed by caspase-9 and Apaf-1 expression.
Results: All combinations confirmed intrinsic apoptosis activation and NF-κB inactivation.
Conclusion: Double and triple combination regimens that target induction of the same death mechanism with reduced dosage of each drug could potentially be clinically beneficial in reducing dose-related toxicities.