title: Relationship between LAPTM4B Gene Polymorphism and Prognosis of Patients following Tumor Resection for Colorectal and Esophageal Cancers.
abstract: BACKGROUND
  Lysosome-associated transmembrane-4 beta (LAPTM4B) is an oncogene that participates tumorgenesis in a variety of human solid tumors, and it has two alleles named as LAPTM4B*1 and *2. The present study aimed to identify the association of LAPTM4B genotype with clinicopathological features and prognosis in colorectal and esophageal cancer patients.
  
  
  METHODS
  Genotypes of LAPTM4B were determined by PCR in 167 colon cancer cases (72 patients in a discovery cohort and 95 patients in a testing cohort), 160 rectal cancer cases and 164 esophageal cancer cases. Association between the LAPTM4B gene polymorphism and clinicopathological variables was calculated by Chi-square test or Fisher's exact test. Patient survival differences were calculated by the Kaplan-Meier method. Prognostic factors were determined with Log-rank test and Cox regression model.
  
  
  RESULTS
  LAPTM4B *1/1 was more frequently detected in colon cancer patients with lymph node metastasis and TNM III+IV stages in total colon cancer (discovery + testing cohorts). LAPTM4B *2/2 decreased in recurrent patients in total colon cancer patients (P = 0.045). Kaplan-Meier survival curves and Log-rank test showed that LAPTM4B*1 was correlated with shorter overall survival (OS) in discovery and testing cohorts of colon cancer (P = 0.0254 and 0.0292, respectively), but not in rectal and esophageal cancer cases (P = 0.7669 and 0.9356, respectively). Multivariate analysis showed that LAPTM4B genotype was an independent prognostic factor for OS in total colon cancer [P = 0.004, hazard ratio (HR) = 0.432; 95% confidence interval (CI) = 0.243-0.768], but not in rectal and esophageal cancers (P = 0.791, HR = 1.073, 95% CI = 0.638-1.804 and 0.998, HR = 1.000, 95% CI = 0.663-1.530, respectively).
  
  
  CONCLUSIONS
  These findings suggested that LAPTM4B allele *1 was a risk factor associated with poor prognosis in patients with colon cancer, but not in patients with rectal or esophageal cancers. LAPTM4B genotype status might be a useful prognostic indicator for patients that need surgical operation in colon cancer.
authors.affiliation: Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Division of Gastrointestinal Cancer Translational Research Laboratory, Peking University Cancer Hospital & Institute, Beijing, China.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Cheng
authors.affiliation: Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Hepato-Pancreato-Biliary Surgery, Peking University Cancer Hospital & Institute, Beijing, China.
authors.forename: Xiuyun
authors.initials: X
authors.lastname: Tian
authors.affiliation: Department of Gastrointestinal Surgery, Peking University Cancer Hospital & Institute, Beijing, China.
authors.forename: Xiaojiang
authors.initials: X
authors.lastname: Wu
authors.affiliation: Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Division of Gastrointestinal Cancer Translational Research Laboratory, Peking University Cancer Hospital & Institute, Beijing, China.
authors.forename: Xiaofang
authors.initials: X
authors.lastname: Xing
authors.affiliation: Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Division of Gastrointestinal Cancer Translational Research Laboratory, Peking University Cancer Hospital & Institute, Beijing, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Du
authors.affiliation: Department of Nosocomial Infection Prevention and Control, Beijing Friendship Hospital, Capital Medical University, Beijing, China.
authors.forename: Chunlian
authors.initials: C
authors.lastname: Zhou
authors.affiliation: Department of Clinical Laboratory, Peking University Cancer Hospital & Institute, Beijing, China.
authors.forename: Qingyun
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Hepato-Pancreato-Biliary Surgery, Peking University Cancer Hospital & Institute, Beijing, China.
authors.forename: Chunyi
authors.initials: C
authors.lastname: Hao
authors.affiliation: Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Division of Gastrointestinal Cancer Translational Research Laboratory, Peking University Cancer Hospital & Institute, Beijing, China.
authors.forename: Xianzi
authors.initials: X
authors.lastname: Wen
authors.affiliation: Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Division of Gastrointestinal Cancer Translational Research Laboratory, Peking University Cancer Hospital & Institute, Beijing, China.|Department of Gastrointestinal Surgery, Peking University Cancer Hospital & Institute, Beijing, China.
authors.forename: Jiafu
authors.initials: J
authors.lastname: Ji
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000401:mortality* / Q000473:pathology; D018572:Disease-Free Survival; D004938:Esophageal Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D005838:Genotype; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D008875:Middle Aged; D015513:Oncogene Proteins / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic / Q000235:genetics*; D011379:Prognosis; D016016:Proportional Hazards Models; D012307:Risk Factors
chemical_list: D014408:Biomarkers, Tumor; C477083:LAPTM4B protein, human; D008565:Membrane Proteins; D015513:Oncogene Proteins