Expression of ABCG2 Protein in Prostate Cancer Tissues and its Clinical Significance

BAI Zhi-peng; TANG Yi-zhong; CHEN Guo-jun

doi:10.3969/j.issn.1002-3429.2019.03.012

Abstract：Objective To investigate the expression of ABCG2 protein in prostate cancer (PCa) tissues and its clinical significance. Methods Ninety-six patients with PCa admitted to our hospital from May 2008 to December 2014 were selected as the study subjects. Ninety-six cases of intraoperatively resected PCa tissues were collected as the observation group, and 96 cases of adjacent normal tissues as the control group. Age, tumor diameter, clinical stage, tumor differentiation, lymph node metastasis and bone metastasis of all patients were recorded. The expression of ABCG2 protein was compared and the factors affecting the prognosis of prostate cancer were analyzed. Results The positive expression rate of ABCG2 protein in PCa tissues (72.92％) was significantly higher than that in adjacent normal tissues (16.67％), and there was a statistically significant difference between the two groups (P＜0.001). The positive expression rate of ABCG2 protein was significantly higher in PCa patients with poorly differentiated tumors, clinical stage C+D stage, bone metastasis and lymph node metastasis (P＜0.05). Ninety-six PCa patients survived for 10 to 52 months from the time of hospital discharge to the end of follow-up, with a median survival of 34.6 months. The 1-, 3-, and 5-year survival rates after discharge were 62.50％ (60/96), 50.00％ (48/96), and 35.42％ (34/96), respectively. Specifically, the 5-year overall survival rates of PCa patients with positive and negative ABCG2 protein were 28.57％ (20/70) and 53.85％ (14/26), respectively, and there was significant difference between the two groups (P=0.021). Multivariate Cox proportional hazard regression model showed that poor differentiation, clinical stage C+D stage, bone metastasis and lymph node metastasis were independent risk factors that affected the prognosis of PCa patients (P＜0.05). Conclusion The positive expression of ABCG2 protein is an independent risk factor for prognosis of PCa patients. Therefore, it can be used clinically as one of effective indicators to assess the condition and prognosis of PCa patients.