title: ABCG2 is a potential prognostic marker of overall survival in patients with clear cell renal cell carcinoma.
abstract: ATP-binding cassette sub-family G member 2 (ABCG2) is a semi-transport protein that plays a major role in multidrug resistance. We aimed to evaluate the prognostic significance of ABCG2 expression in patients with clear cell renal cell carcinoma.
  
  
  
  From 2008 to 2013, 120 patients with clear cell kidney cancer underwent surgery with paraffin-embedded specimens and necessary clinical information available. Immunohistochemistry staining was performed to grade the expression of ABCG2 as ABCG2(-): less than 10% of tumor cells stained; ABCG2(+): weak membrane staining; and ABCG2(++): moderate or strong membrane staining. The overall survival was analyzed using Kaplan-Meier method. Multivariable Cox regression evaluated the independent predictors for overall survival.
  
  
  
  ABCG2(-) was diagnosed in 57 (48%) patients, ABCG2(+) in 52 (43%) patients, and ABCG2 (++) in 11(9.2%) patients. ABCG2 expression significantly correlated with the five-year survival (p < 0.001) and distant metastasis (p = 0.001). In the multivariable analysis, besides Fuhrman grade, the ABCG2 expression was an independent prognostic marker for overall survival (p < 0.001) when incorporating other relevant tumor and clinical parameters (HR = 3.84, 95% CI: 1.92-7.70).
  
  
  
  The current data suggests that ABCG2 may serve as a prognostic marker for overall survival in patients with clear cell renal cell carcinoma. Further studies with large cohorts of patients will be essential for validating these findings and defining the clinical utility of ABCG2 in the patient population.
authors.affiliation: Department of Urology, Ruijin Hospital, Shanghai JiaoTong University School of Medicine, Building 6th, Floor 6th, 197# Ruijin 2nd road, Shanghai, 200025, China.
authors.forename: Haofei
authors.initials: H
authors.lastname: Wang
authors.affiliation: Ruijin North Hospital, Department of Pathology, Shanghai JiaoTong University School of Medicine, Shanghai, 201801, China.
authors.forename: Fangxiu
authors.initials: F
authors.lastname: Luo
authors.affiliation: Department of Stem Cell Biology and Regenerative Medicine, Cleveland Clinic, Lerner Research Institute, Cleveland, OH, 44195, USA.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: Department of Urology, Ruijin Hospital, Shanghai JiaoTong University School of Medicine, Building 6th, Floor 6th, 197# Ruijin 2nd road, Shanghai, 200025, China.
authors.forename: Zhaoping
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Department of Urology, Ruijin Hospital, Shanghai JiaoTong University School of Medicine, Building 6th, Floor 6th, 197# Ruijin 2nd road, Shanghai, 200025, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Huang
authors.affiliation: Ruijin North Hospital, Department of Pathology, Shanghai JiaoTong University School of Medicine, Shanghai, 201801, China.
authors.forename: Renyi
authors.initials: R
authors.lastname: Ma
authors.affiliation: Department of Urology, Ruijin Hospital, Shanghai JiaoTong University School of Medicine, Building 6th, Floor 6th, 197# Ruijin 2nd road, Shanghai, 200025, China.
authors.forename: Hongchao
authors.initials: H
authors.lastname: He
authors.affiliation: Department of Urology, Ruijin Hospital, Shanghai JiaoTong University School of Medicine, Building 6th, Floor 6th, 197# Ruijin 2nd road, Shanghai, 200025, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Department of Urology, Ruijin Hospital, Shanghai JiaoTong University School of Medicine, Building 6th, Floor 6th, 197# Ruijin 2nd road, Shanghai, 200025, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Shao
authors.affiliation: Department of Urology, Ruijin Hospital, Shanghai JiaoTong University School of Medicine, Building 6th, Floor 6th, 197# Ruijin 2nd road, Shanghai, 200025, China. zhaojp01@126.com.
authors.forename: Juping
authors.initials: J
authors.lastname: Zhao
mesh_terms: D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2 / Q000235:genetics*; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics; D002292:Carcinoma, Renal Cell / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D018572:Disease-Free Survival; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000235:genetics*; D009367:Neoplasm Staging; D011379:Prognosis
chemical_list: C116614:ABCG2 protein, human; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins
keywords: ABCG2; ATP-binding-cassette transporters; Biomarker; Overall survival; Renal cancer