ABSTRACT
@#[Abstract] Objective: To explore the clinical significance and in vitro biological effect of ubiquitin carboxyl-terminal hydrolase L5 (UCHL5) expression in thyroid carcinoma (TC) tissues. Methods: TCGAdata were used to analyze the expression of UCHL5 in thyroid carcinoma tissues and its relationship with the prognosis of patients. 82 pairs of TC tissues and corresponding adjacent tissues were collected in the Department of Vascular and Thyroid Surgery, Sichuan Provincial People's Hospital from May 2018 to July 2019; TC cell lines (KTC-1 and WRO) were cultured in vitro, and transfected with UCHL5 overexpression vectors or their control vectors via lentivirus. The mRNAand protein expressions of UCHL5 and B-Raf proto-oncogene serine/threonine-protein kinase (BRAF) in tissues and cells were detected by qPCR and Western blotting, respectively. Cell proliferation was detected by CCK-8, and cell invasion and migration were detected by Transwell and Wound-healing experiments. Results: The expression of UCHL5 was low in TC tissues (P<0.01), and its expression was upregulated in tumor tissues with high TNM stage (P<0.01). The expression of UCHL5 was significantly correlated with BRAF expression and TNM stage of patients (all P<0.01), but not significantly related with patient's age, gender, pathological type and BRAF mutation (all P>0.05). In vitro overexpression of UCHL5 in KTC-1 and WRO cells could significantly promote BRAF expression, cell proliferation and metastasis (all P<0.01). Conclusion: The expression of UCHL5 is low in TC tissue, but upregulated with tumor progression. The high expression of UCHL5 in TC patients suggests poor prognosis. Meanwhile, UCHL5 can promote the malignant behaviors of TC cells in vitro.
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.