Effect of Recombinant Plasmid pEGFP-AFP-hTNF on Liver Cancer Cells (HepG2 Cells) in vitro when Delivered by PEG-PEI/Fe3O4 Nanomagnetic Fluid

Gene delivery into liver cancer cells has been a problem. This study aimed to understand the effect of using PEGI/Fe3O4 nanomagnetic fluid as a gene vector for liver cancer gene therapy. An AFP enhancer aids in the expression of tumor-specific foreign genes in AFP-producing cancer cells like HepG2 cells, and was utilized in the delivery method in this study. Methods: We constructed recombinant plasmid PEGFP-AFP-hTNFα, which was transfected into AFP positive HepG2 cells and AFP negative Hela cells by PEG-PEI/Fe3O4 nanomagnetic fluid. Fluorescence microscopy was used to evaluate the transfection rate of the hTNFα gene in the HepG2 cells 12 hours after transfection. Reverse transcription polymerase chain reaction (RT-PCR) and western blot were used to detect expression of hTNFα gene in the HepG2 cells 48 hours after transfection. Methyl thiazolyl tetrazolium (MTT) assay was used to evaluate the inhibitory effect of hTNFα on the proliferation of HepG2 cells. Flow cytometry was used to analyze the apoptosis of HepG2 cells. Results: Plasmid PEGFP-AFP-hTNFα delivered by PEG-PEI/Fe3O4 nanomagnetic fluid was successfully transfected into HepG2 cells and expressed in the HepG2 cells. The transfection efficacy of hTNFα gene delivered by PEG-PEI/Fe3O4 nanomagnetic fluid was superior to that of hTNFα gene delivered by lipofectamine in HepG2 cells. RT-PCR and western blot demonstrated that hTNFα gene was expressed in HepG2 cells that were transfected with complexes of nanomagnetic fluid/PEGFP-AFP-hTNFα. MTT and flow cytometry showed that the hTNFα gene markedly exerted a cell killing effect. Conclusion: PEG-PEI/Fe3O4 nanomagnetic fluid successfully transfected PEGFP-AFP-hTNFα into HepG2 cells and induced expression of hTNFα gene in the HepG2 cells, thus showing promise as a gene vector for liver cancer gene therapy. Furthermore, an AFP enhancer can specifically increase the expression of target genes in cells positive for AFP

MicroRNA-647 Targets SRF-MYH9 Axis to Suppress Invasion and Metastasis of Gastric Cancer

MicroRNAs (miRNAs) play important roles in regulating tumour development and progression. Here we show that miR-647 is repressed in gastric cancer (GC), and associated with GC metastasis. Moreover, we identify that miR-647 can suppress GC cell migration and invasion in vitro. Mechanistically, we confirm miR-647 directly binds to the 3' untranslated regions of SRF mRNA, and SRF binds to the CArG box located at the MYH9 promoter. CCG-1423, an inhibitor of RhoA/SRF-mediated gene transcription, inhibits the expression of MYH9, especially in SRF downregulated cells. Overexpression of miR-647 inhibits MGC 80-3 cells' metastasis in orthotropic GC models, but increasing SRF expression in these cells reverses this change. Importantly, we found the synergistic inhibition effect of CCG-1423 and agomir-647, an engineered miRNA mimic, on cancer metastasis in orthotropic GC models. Our study demonstrates that miR-647 functions as a tumor metastasis suppressor in GC by targeting SRF/MYH9 axis