2024, 40(7): 1382-1389.
DOI: 10.12449/JCH240716
Abstract:
Objective To investigate the regulatory effect of miRNA-933 on the apoptosis and proliferation of human hepatic stellate cell line LX-2 and its mechanism. Methods Firstly, with human liver tissue for research, gene microarray technology was used to detect the differentially expressed genes in liver tissue between liver cirrhosis/chronic hepatitis B tissue and normal liver tissue, among which the significantly differentially expressed miRNAs were identified, and thus miRNA-933 was determined as the research object. Then, with the human hepatic stellate cell line LX-2 for research, miRNA-933 mimic and inhibitor (miRNA-933 siRNA) were used to construct the LX-2 models of overexpression and knockdown, and the cells transfected with mimic-NC (overexpression) or siRNA-NC (knockdown) were established as the negative control group. Quantitative real-time PCR and Western blot were used to measure the expression levels of miRNA-933 and activation biomarkers; techniques such as cell proliferation assay and flow cytometry were used to investigate the effect and mechanism of miRNA-933 on cell apoptosis, proliferation, and activation. The independent-samples t test was used for comparison of continuous data between two groups; a one-way analysis of variance was used for comparison between multiple groups, and Bonferroni correction was also performed. Results A total of 18 significantly differentially expressed miRNAs were obtained based on the results of gene microarray, among which miRNA-933 was significantly downregulated (P<0.05). After LX-2 cells were transfected with miRNA-933 mimic or siRNA, compared with the negative control group, miRNA-933 siRNA significantly downregulated the expression of miRNA-933 (P=0.000 7), while miRNA-933 mimic significantly upregulated the expression of miRNA-933 (P=0.000 3). Western blot and quantitative real-time PCR showed that miRNA-933 siRNA significantly upregulated the expression of collagen I and α-SMA (P<0.001), while miRNA-933 mimic significantly inhibited the expression of collagen I and α-SMA (P<0.05). Flow cytometry showed that compared with the negative control group, miRNA-933 siRNA significantly downregulated the apoptosis rate of LX-2 cells (P=0.031 9), and miRNA-933 mimic significantly upregulated the apoptosis rate of LX-2 cells (P=0.005 5). Western blot showed that compared with the negative control group, miRNA-933 siRNA could inhibit the expression of Caspase-3 (P=0.006 7) and poly(ADP-ribose) polymerase-1 (PARP-1) (P=0.003 0) and upregulate the expression of B-cell lymphoma-2 (Bcl-2) in LX-2 cells (P=0.002 0), while miRNA-933 mimic could significantly upregulate the expression of Caspase-3 (P=0.011 8) and PARP-1 (P=0.049 5) and downregulated the expression of Bcl-2 (P=0.002 1). Cell proliferation assay showed that compared with the negative control group, miRNA-933 siRNA could promote the proliferation of LX-2 cells (P=0.011 5), while on the contrary, miRNA-933 mimic could inhibit the proliferation of LX-2 cells (P=0.001 2). Western blot and quantitative real-time PCR showed that miRNA-933 siRNA significantly inhibited the expression of Kruppel-like factor 6 (KLF6) and downregulated the expression of activating transcription factor 4 (ATF4), activating transcription factor 3 (ATF3), and C/EBP homologous protein (CHOP), while miRNA-933 mimic promoted the expression of the above proteins (all P<0.05). Conclusion This study shows that miRNA-933 may promote cell apoptosis and inhibit cell activation and proliferation by promoting the activation of the KLF6/ATF4/ATF3/CHOP/Bcl-2 signal axis in LX-2 cells.
HAI L, MA LN, LUO X, et al. Effect of miRNA-933 on the apoptosis and proliferation of LX-2 cells and its molecular mechanism[J]. J Clin Hepatol, 2024, 40(7): 1382-1389.. doi: 10.12449/JCH240716.