title: Overexpression of Transient Receptor Protein Cation Channel Subfamily A Member 1, Confers an Independent Prognostic Indicator in Nasopharyngeal Carcinoma.
abstract: BACKGROUND
  Detection of oncogenes provides chances to understand tumor development and progression. Transient receptor protein cation channel subfamily A, member 1 (TRPA1) transcript was significantly upregulated in nasopharyngeal carcinoma (NPC) with a stepwise upregulation from low- to high-stage NPCs from a preliminary data analysis in the Gene Expression Omnibus database. The TRPA1 gene is a member of the TRP channel family, encoding integral membrane proteins that functions as cation channels. Loss of calcium homeostasis takes place in cancer cells.
  
  
  METHODS
  Immunostaining of TRPA1 was analyzed on 124 biopsies from NPC patients retrospectively. The H-score method was used to evaluate the immunoexpression of TRPA1. The correlations between H-score of TRPA1 protein level and clinicopathological factors, as well as the significances of TRPA1 protein level for disease-specific, distal-metastasis-free and local recurrence-free survivals were assessed.
  
  
  RESULTS
  These patients were characterized to be no initial metastasis and medicated with the traditional procedure. The TRPA1 score was found to be associated with clinicopathological parameters and patient survivals. Along with the guideline of 7(th) edition of the American Joint Committee on Cancer, we found that TRPA1 upregulation (50%) was associated with advanced primary tumor (P = 0.009) and overall clinical stage (P = 0.019). In univariate log-rank testing, primary tumor, nodal status, stage and TRPA1 protein level significantly contributed to worse disease-specific survival, distal metastasis-free survival and local recurrence-free survival. In multivariate analysis, high TRPA1 protein level and tumor stage emerged as independent prognostic indicators for inferior disease-specific survival (P = 0.014; P = 0.003), distal metastasis-free survival (P = 0.004; P = 0.034) and recurrence-free survival (P = 0.017; P = 0.015).
  
  
  CONCLUSIONS
  The upregulation of TRPA1 protein level is frequently correlated to unfavorable prognosticators and gives rise to cancer progression in NPC patients.
authors.affiliation: 1. Departments of Pathology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan;; 2. Department of Pathology, Chang Gung Memorial Hospital, Chia-Yi, Taiwan;
authors.forename: You-Ting
authors.initials: YT
authors.lastname: Wu
authors.affiliation: 1. Departments of Pathology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan;
authors.forename: Shao-Lun
authors.initials: SL
authors.lastname: Yen
authors.affiliation: 3. Department of Pathology, Chi-Mei Medical Center, Tainan, Taiwan;; 4. National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan;; 5. Department of Biotechnology, Southern Taiwan University of Science and Technology, Tainan, Taiwan;; 6. Institute of Clinical Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan;
authors.forename: Chien-Feng
authors.initials: CF
authors.lastname: Li
authors.affiliation: 3. Department of Pathology, Chi-Mei Medical Center, Tainan, Taiwan;
authors.forename: Ti-Chun
authors.initials: TC
authors.lastname: Chan
authors.affiliation: 3. Department of Pathology, Chi-Mei Medical Center, Tainan, Taiwan;
authors.forename: Tzu-Ju
authors.initials: TJ
authors.lastname: Chen
authors.affiliation: 7. Department of Radiation Oncology, Chi-Mei Medical Center, Liouying, Tainan, Taiwan;
authors.forename: Sung-Wei
authors.initials: SW
authors.lastname: Lee
authors.affiliation: 8. Department of Pathology, E-DA Hospital, I-Shou University, Kaohsiung, Taiwan;; 9. Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan;
authors.forename: Hong-Lin
authors.initials: HL
authors.lastname: He
authors.affiliation: 8. Department of Pathology, E-DA Hospital, I-Shou University, Kaohsiung, Taiwan;
authors.forename: I-Wei
authors.initials: IW
authors.lastname: Chang
authors.affiliation: 10. Department of Anesthesiology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan;
authors.forename: Chung-Hsi
authors.initials: CH
authors.lastname: Hsing
authors.affiliation: 9. Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan;; 11. Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan;; 12. Doctoral degree program in Marine Biotechnology, National Sun Yat-sen University, Kaohsiung, Taiwan.
authors.forename: Yow-Ling
authors.initials: YL
authors.lastname: Shiue
keywords: TRPA1; nasopharyngeal carcinoma; prognosis.