Influence of UCHL5 on proliferation and apoptosis of SW527 breast cancer cells / 中华肿瘤杂志

ABSTRACT

Objective@#To investigate the effect of UCHL5 on proliferation and apoptosis of breast cancer cells.@*Methods@#SW527 cells were infected with lentiviral vector carrying short hairpin RNA to delete the expression of UCHL5. 3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay was used to examine cell proliferation, and subcutaneous transplantation experiments were performed to detect tumor growth. Cell apoptosis was detected using Annexin V/ Propidium iodide (PI) double staining. The correlation between UCHL5 expression and the expressions of proliferation and apoptosis associated genes was analyzed using TCGA breast invasive carcinoma data set. The relationship between UCHL5 expression and breast cancer patients′survival was analyzed using Kaplan-Meier Plotter online tool.@*Results@#After knockdown of UCHL5, A values of SW527 cells on day 2 and day 4 were 0.822±0.017 and 1.045±0.023, respectively, which were significantly lower than 0.976±0.016 and 1.284±0.025 of control cells on day 2 and day 4 (P<0.001). In vivo xenografted mouse model, the volume in UCHL5-suppressed group was (166.90±75.05) mm3, significantly smaller than (329.80±35.84) mm3 in control group (P=0.029). Flow cytometry analysis showed the apoptotic rate of SW527 cells was (8.60±1.13)% after knockdown of UCHL5, significantly higher than (2.95±0.07)% of control group (P=0.020). TCGA database analysis showed that the expression of UCHL5 was positively correlated with the expressions of genes related to cell proliferation, in paralled with the increased expression of UCHL5, the expression of the pro-apoptosis associated genes was decreased. Kaplan-Meier Plotter analysis demonstrated that the overall survival and relapse-free survival of breast cancer patients with high expression of UCHL5 were much shorter (all P<0.001).@*Conclusions@#Down-regulation of UCHL5 inhibits the proliferation and tumor formation and promotes apoptosis of SW527 cells. High expression of UCHL5 may predict poor prognosis of breast cancer patients.