title: LAPTM4B allele *2 is associated with breast cancer susceptibility and prognosis.
abstract: BACKGROUND
  Lysosome-associated protein transmembrane 4 beta (LAPTM4B) has two alleles named LAPTM4B*1 and LAPTM4B*2. Allele *1 contains only one copy of a 19-bp sequence at the 5'UTR in the first exon, whereas this sequence of allele*2 is duplicated and arrayed as a tandem repeat. Previous studies revealed that LAPTM4B polymorphisms contribute to the risk of certain types of cancers. This study aimed to investigate the polymorphism of LAPTM4B in breast cancer by analysis the correlation of LAPTM4B genotype with breast cancer susceptibility, clinicopathologic features and prognosis.
  
  
  METHODS
  Genotyping of the LAPTM4B polymorphism was determined by PCR method. The expression levels of LAPTM4B in breast cancer tissues and breast cancer cell lines were determined by quantitative reverse-transcription PCR (qRT-PCR) analysis. The correlation of LAPTM4B genotype with clinicopathologic parameters and prognosis were assessed statistically.
  
  
  RESULTS
  The results of qRT-PCR analysis indicated that LAPTM4B*2 was associated with the higher level of LAPTM4B expression compared with the LAPTM4B*1 in both breast cancer cell lines and breast cancer tissues. We found that LAPTM4B*2 was associated with an increased risk for breast cancer. LAPTM4B*2 was significantly associated with higher histopathologic grade, lymph node metastasis and poor prognosis.
  
  
  CONCLUSIONS
  LAPTM4B*2 is a risk factor associated with breast cancer susceptibility and poor prognosis. LAPTM4B*2 may be a potential predicative marker for the susceptibility, progression and metastasis of breast cancer.
authors.affiliation: Department of Breast Surgery, Qilu Hospital, Shandong University, Jinan, Shandong, People's Republic of China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Li
authors.forename: Xiangnan
authors.initials: X
authors.lastname: Kong
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.forename: Ning
authors.initials: N
authors.lastname: Zhang
authors.forename: Liyu
authors.initials: L
authors.lastname: Jiang
authors.forename: Tingting
authors.initials: T
authors.lastname: Ma
authors.forename: Qifeng
authors.initials: Q
authors.lastname: Yang
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000235:genetics*; D018450:Disease Progression; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics*; D008875:Middle Aged; D008957:Models, Genetic; D015513:Oncogene Proteins / Q000235:genetics*; D011110:Polymorphism, Genetic; D011379:Prognosis; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D012307:Risk Factors
chemical_list: D014408:Biomarkers, Tumor; C477083:LAPTM4B protein, human; D008565:Membrane Proteins; D015513:Oncogene Proteins