title: Expression and significance of glucose transporter-1, P-glycoprotein, multidrug resistance-associated protein and glutathione S-transferase-π in laryngeal carcinoma.
abstract: Increasing glucose transporter-1 (GLUT-1) activity is one of the most important ways to increase the cellular influx of glucose. We previously demonstrated that increased GLUT-1 expression was an independent predictor of survival in patients with laryngeal carcinoma. Thus, GLUT-1 may present a novel therapeutic target in laryngeal carcinoma. In this study, the expression of GLUT-1, P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1) and glutathione S-transferase-π (GST-π) in laryngeal carcinomas was investigated by immunohistochemistry. Additionally, possible correlations between GLUT-1 and P-gp, MRP1 and GST-π and various clinicopathological parameters were analyzed. In this study, 52.9% (18/34), 58.8% (20/34), 20.6% (7/34) and 58.8% (20/34) of the laryngeal carcinomas were positive for GLUT-1, P-gp, MRP1 and GST-π, respectively. The expression of GLUT-1, P-gp, MRP1 and GST-π was higher in laryngeal carcinoma specimens when compared with laryngeal precancerous lesions (P<0.05). Pearson's correlation analysis showed correlations between GLUT-1 and P-gp (r=0.364; P=0.034), GLUT-1 and MRP1 (r=0.359; P=0.037) and P-gp and GST-π (r=0.426; P=0.012). GLUT-1 expression was found to significantly correlate with tumor-node-metastasis classification (P=0.02) and clinical stage (P=0.037). Furthermore, P-gp was found to significantly correlate with clinical stage (P=0.026). Univariate analysis showed that MRP1 expression was significantly associated with poor survival (c2=5.16; P=0.023). Multivariate analysis revealed that lymph node metastasis (P=0.009) and MRP1 overexpression (P=0.023) were significant predictors of poor survival. In the present study, the expression of GLUT-1, P-gp, MRP1 and GST-π in laryngeal carcinomas was investigated, as well as the correlations between these proteins. P-gp was found to significantly correlate with clinical stage, while MRP1 overexpression was significantly associated with poor survival.
authors.affiliation: Department of Otolaryngology, The Second Hospital of Shaoxing City, Shaoxing, Zhejiang 312000, P.R. China.
authors.forename: Zhong-Ping
authors.initials: ZP
authors.lastname: Mao
authors.affiliation: Department of Otolaryngology, The Second Hospital of Shaoxing City, Shaoxing, Zhejiang 312000, P.R. China.
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Zhao
authors.affiliation: Department of Otolaryngology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, P.R. China.
authors.forename: Shui-Hong
authors.initials: SH
authors.lastname: Zhou
authors.affiliation: Department of Pathology, The Second Hospital of Shaoxing City, Shaoxing, Zhejiang 312000, P.R. China.
authors.forename: Meng-Qin
authors.initials: MQ
authors.lastname: Liu
authors.affiliation: Department of Pathology, The Second Hospital of Shaoxing City, Shaoxing, Zhejiang 312000, P.R. China.
authors.forename: Wei-Feng
authors.initials: WF
authors.lastname: Tan
authors.affiliation: Department of Pathology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, P.R. China.
authors.forename: Hong-Tian
authors.initials: HT
authors.lastname: Yao
keywords: P-glycoprotein; glucose transporter-1; glutathione-s-transferase-π; laryngeal carcinoma; multidrug resistance-associated protein