Prognosis value of immune-related gene CEBPB in clear cell renal cell carcinoma / 中华泌尿外科杂志

ABSTRACT

Objective:To explore the correlation between CCAAT enhancer binding protein beta (CEBPB) expression and clinical characteristics in ccRCC, and to investigate the effect of CEBPB on proliferation and invasion of ccRCC cells.Methods:Between March 2020 to December 2020, the transcriptome and clinical data of 537 ccRCC cases were downloaded from TCGA database, and the correlation of CEBPB expression with clinical characteristics of ccRCC were analyzed. Univariate and multivariate Cox regression analysis were used to determine the effect of CEBPB expression on the prognosis of ccRCC patients. The correlation between CEBPB expression and immunocyte infiltration in ccRCC was investigated via TIMER database. The expression levels of CEBPB mRNA and protein in human renal tubular epithelial cell line HK2 and ccRCC cell lines (Caki-1, ACHN, 786O, 769P and A498) were determined by real-time PCR and western blot, respectively. After transfected with NC siRNA or CEBPB siRNA for 48 h, the proliferation and invasion of ACHN cells and 786O cells were determined by using MTT assay and invasion assay, respectively.Results:TCGA databases analysis revealed that, compared with normal kidney tissue, the expression of CEBPB mRNA in ccRCC was up-regulated by 2.55-fold ( P<0.05). CEBPB expression was positively correlated with age, tumor grade, tumor stage, lymph node metastasis and distant metastasis ( P<0.05). The tumor grade ( HR=1.703, P=0.040), tumor stage( HR=1.773, P=0.026), distant metastasis ( HR=3.080, P<0.001) and the high expression of CEBPB ( HR=1.874, P=0.003) were independent poor prognostic factors for ccRCC patients. The analysis results by using TIMER database showed that CEBPB expression was positively correlated with infiltrating levels of B cells (Rho=0.168), M2 macrophages (Rho=0.373), Tregs (Rho=0.348), neutrophils (Rho=0.194), and natural killer T cell (Rho=0.421) in ccRCC. The expression level of CEBPB mRNA in Caki-1, ACHN, 786O, 769P and A498 cells was (9.43±1.25)-fold, (5.44±0.82)-fold, (4.50±0.52)-fold, (4.88±0.73)-fold and (7.50 ± 1.04)-fold of HK2 cells, respectively. The expression level of CEBPB protein was (6.22±0.45)-fold, (5.84±0.85)-fold, (6.51±0.55)-fold, (6.23±0.62)-fold and (3.84±0.45)-fold of HK2 cells, respectively ( P<0.05). MTT assay showed that the proliferation rates of ACHN cells and 786O cells at 24, 48, 72, 96 h were (98.4±1.7)% and (99.0±1.4)%, (97.8±2.1)% and (98.5±1.5)%, (101.3±1.2)% and (97.6±1.7)%, (97.5±2.0)% and (99.1±1.3)% in NC siRNA group, and (68.8±5.8)% and (79.5±6.2)%, (57.9 ± 6.1)% and (70.8±5.1)%, (50.9±4.6)% and (66.8±4.9)%, (43.2±5.0)% and (60.5±5.3)% in CEBPB siRNA group. Compared with NC siRNA group, the proliferation activity of ACHN cells and 786O cells was significantly inhibited in the CEBPB siRNA group ( P<0.05). Cell invasion assay showed that the invasion activity of ACHN cells and 786O cells were (95.0±5.2)% and (97.3±4.4)% in NC siRNA group, (35.2±5.4)% and (26.7±3.3)% in CEBPB siRNA group, respectively ( P<0.05). Compared with NC siRNA group, the invasion activity of ACHN cells and 786O cells were significantly inhibited in the CEBPB siRNA group ( P<0.05). Conclusions:CEBPB was highly expressed in ccRCC, which was closely related to the prognosis and immunocyte infiltration of ccRCC patients. Silencing the expression of CEBPB significantly inhibited the proliferation and invasion of ccRCC cells