Correlation between LAT1 expression level and risk of postoperative relapse in patients with non-muscle invasive bladder cancer

Abstract:

Objective To explore the correlation between the expression level of L-type amino acid transporter 1（LAT1） and the risk of postoperative relapse in patients with non-muscle-invasive bladder cancer（NMIBC）.Methods A total of 108 patients with NMIBC who received surgical treatment in Yongchuan Hospital Affiliated to Chongqing Medical University from February 2021 to February 2022 were selected as subjects. LAT1 expression levels in the bladder cancer tissue （from the sites where tumor was identified） and paracancerous tissue（from adjacent normal areas） were measured by reverse transcriptase polymerase chain reaction，and the expression levels of LAT1 in the two types of tissue were compared. Meanwhile，all patients were divided into high expression group and low expression group according to the second quantile of LAT1 expression in the bladder cancer tissue，and the clinicopathological parameters of the two groups were compared. The two groups were observed and followed up for 12 months for postoperative relapse. The Kaplan-Meier curve was used to analyze and compare the risk of postoperative relapse between the two groups. The multivariate Cox proportional hazards regression model was used to determine the influencing factors for postoperative relapse.Results The LAT1 expression level in the bladder cancer tissue（1.80±0.35） was significantly higher than that in the paired paracancerous tissue（1.05±0.17）（P<0.05）. The proportion of patients with a smoking history and clinical stage T₁ was significantly higher in the high LAT1 expression group than in the low LAT1 expression group（P<0.05）. The mean follow-up time of 108 patients with bladder tumor was （10.84±1.94） months. Among these patients，33 had a relapse，with a relapse rate of 30.56%. The Kaplan-Meier curve showed that the overall relapse rate was significantly higher in patients with high LAT1 expression than in those with low LAT1 expression（log rank χ2=4.382，P=0.036）；the multivariate Cox regression analysis showed that smoking history [hazard ratio（HR）=6.539，95%CI=2.439-17.531]，clinical stage T₁（HR=3.658，95%CI=1.808-7.398），and high LAT1 expression（HR=3.425，95%CI=1.631-7.191） were risk factors for postoperative relapse of patients with NMIBC P<0.05）.Conclusion The LAT1 expression level is high in the bladder cancer tissue，and high LAT1 expression levels may be correlated with an increased risk of postoperative relapse in patients with bladder cancer.