METHODS: In this study, transfection of VP3 and silencing of CD147 genes was achieved through the treatment of tumors with pVIVO1-GFP/VP3 (VP3), psiRNA-CD147/2 (shCD147/2), and their combination of CT26 colon cancer cell-induced in mice. The effectiveness of tumor-treatment was ascertained by electrophoresis, TUNEL assay, and flow cytometry analysis. While histopathological and biochemical analysis were used as toxic side effect identification.
RESULTS: The tumor growth delay index (TGDI) after treatment with VP3, shCD147/2, and their combination treatments increased by 1.3-, 1.2-, 2.0- and 2.3-fold respectively, over untreated control. The VP3-shCD147/2 combination treatment was more efficacious then either VP3 or shCD147/2 alone in the retardation of mouse CT26 colorectal cell tumor allograft.
CONCLUSION: The antitumor effect of the combination treatment is the result of synergistic effects of VP3 and shCD147/2 on the tumor cells resulting in apoptosis. Thus, the study shows that combination of VP3 and shCD147/2 treatment can be developed into a potential approach for anticolorectal cancer treatment regimen.
METHODS: siRNA was conjugated with a thermo-responsive copolymer that was synthesized by copolymerization of N-isopropylacrylamide (NIPAAm) and hydrophilic N,N-dimethylacrylamide (DMAA) to permit thermally controlled interaction between siRNA and an intracellular gene silencing-related protein by utilizing the coil-to-globule phase transition of the copolymer. The composition of the copolymer was fine-tuned to obtain lower critical solution temperature (LCST) around body temperature, and the phase transition behavior was evaluated. The cellular uptake and gene silencing efficiency of the copolymer-siRNA conjugates were then investigated in cultured cells.
RESULTS: The siRNA conjugated with the copolymer with LCST of 38.0°C exhibited ~ 11.5 nm of the hydrodynamic diameter at 37°C and ~ 9.8 nm of the diameter at 41°C, indicating the coil-globule transition above the LCST. In line with this LCST behavior, its cellular uptake and gene silencing efficiency were enhanced when the temperature was increased from 37°C to 41°C.
CONCLUSION: By fine-tuning the LCST behavior of the copolymer that was conjugated with siRNA, siRNA activity could be controlled in a thermo-responsive manner around the body temperature. This technique may offer a promising approach to induce therapeutic effects of siRNA selectively in the target site even in the in vivo conditions.
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.