Effects of BAP1, Ki-67 index, and Id-1 in patients with clear cell renal carcinoma and their correlation with clinical features and prognosis

BACKGROUND: Clear cell renal carcinoma (CCRCC) is a multigene-related tumor. The aim of the present study was to analyze the expression of breast cancer 1-associated protein 1 (BAP1), Ki-67, and inhibitor of differentiation-1 (Id-1) in CCRCC patients and their correlation with clinical features and prognosis. METHODS: A total of 45 CCRCC patients who were diagnosed and treated at our hospital from January 2016 to January 2018 were included in the present study. BAP1, Ki-67, and Id-1 protein expression in the CCRCC tissue group and adjacent mucosa group was compared. The correlation between BAP1, Ki-67, and Id-1 proteins, and the clinical characteristics and the prognosis of CCRCC patients, were analyzed. Multiple logistic regression was used to analyze the risk factors that affect the prognosis of CCRCC patients. RESULTS: The negative rate of BAP1 in the CCRCC group was higher than that in the adjacent mucosa group. There were more patients with a Ki-67 index >10 and a higher Id-1-positive rate in the CCRCC tissue group. BAP-1, Ki-67 index, and Id-1 protein expression were not correlated with age, sex, surgical method, microscopic necrosis, and degree of sarcomatoid characteristics of CCRCC patients (P>0.05), but were related to tumor diameter, pathological stage, TNM stage, and World Health Organization (WHO)/Internal Society of Urologic Pathology (ISUP) grade. The Kaplan-Meier survival curve showed that the average survival time of the BAP1-negative group, Ki-67 index >10 group, and Id-1 protein-positive group was shorter than that of the BAP1-positive group, Ki-67 index ≤10 group, and Id-1 protein-negative group, respectively. Pathological staging, WHO/ISUP classification, negative BAP1, Ki-67 index >10, and positive Id-1 protein were independent risk factors affecting CCRCC patients (P<0.05). CONCLUSIONS: The expression of BAP1 in CCRCC patients decreased, and the expression of Ki-67 and Id-1 protein increased. Abnormal expression levels of BAP1, Ki-67, and Id-1 proteins were involved in the occurrence and development of CCRCC, and closely related to the prognosis of patients. These can be used as molecular markers for predicting the prognosis of CCRCC patients and as potential targets for tumor treatment.