Objective: To analyze the mechanism of metformin in improving oxaliplatin resistance of colorectal cancer cells. Methods: The expression levels of EIF3G in 71 cases of colorectal cancer and adjacent tissues were detected by RT-qPCR. The survival curve was established by Kaplan-Meier method. The survival rate difference between the two groups was compared by Log-rank test.HCT-116 cells were infected with shEIF3G lentivirus, HCT-116 L-OHP-resistant cell line was constructed.After treated with metformin, sensitivity to L-OHP was detected by CCK-8 assay, RT-qPCR and Western blot were used to analyze the EIF3G mRNA and protein levels. The subcutaneous tumor model of nude mice was constructed to observe the effect of metformin on tumor growth. Results: The expression level of EIF3G mRNA in colorectal cancer tissues was up-regulated by (3.24±0.43) times compared with paraneoplastic tissues (P<0.01). EIF3G level was significantly correlated with the prognosis of colon cancer patients. Knockdown EIF3G could enhance the L-OHP sensitivity of HCT116/L-OHP cells (P<0.05); Metformin can reduce the expression level of EIF3G and improve the drug resistance of HCT116/L-OHP cells (P<0.05), and inhibit the development of colorectal cancer in vivo (P<0.05). Conclusion Metformin can inhibit the expression of EIF3G and improve the L-OHP resistance of HCT-116 cells.

The Coronaviridae family is characterized by a nucleocapsid that is composed of the genome RNA molecule in combination with the nucleoprotein (N protein) within a virion. The most striking physiochemical feature of the N protein of SARS-CoV is that it is a typical basic protein with a high predicted pI and high hydrophilicity, which is consistent with its function of binding to the ribophosphate backbone of the RNA molecule. The predicted high extent of phosphorylation of the N protein on multiple candidate phosphorylation sites demonstrates that it would be related to important functions, such as RNA-binding and localization to the nucleolus of host cells. Subsequent study shows that there is an SR-rich region in the N protein and this region might be involved in the protein-protein interaction. The abundant antigenic sites predicted in the N protein, as well as experimental evidence with synthesized polypeptides, indicate that the N protein is one of the major antigens of the SARS-CoV. Compared with other viral structural proteins, the low variation rate of the N protein with regards to its size suggests its importance to the survival of the virus.
Amino Acid Motifs ; genetics ; Amino Acid Sequence ; Antigens, Viral ; immunology ; Base Composition ; Base Sequence ; Cluster Analysis ; Computational Biology ; DNA Primers ; Enzyme-Linked Immunosorbent Assay ; Genetic Variation ; Molecular Sequence Data ; Nucleocapsid Proteins ; genetics ; immunology ; metabolism ; Phosphorylation ; SARS Virus ; genetics ; Sequence Analysis, DNA