title: Clinical Relevance of Liver Kinase B1(LKB1) Protein and Gene Expression in Breast Cancer.
abstract: Liver kinase B1 (LKB1) is a tumor suppressor, and its loss might lead to activation of the mammalian target of rapamycin (mTOR) and tumorigenesis. This study aimed to determine the clinical relevance of LKB1 gene and protein expression in breast cancer patients. LKB1 protein expression was evaluated using immunohistochemistry in tumors from early breast cancer patients in two Taiwanese medical centers. Data on LKB1 gene expression were obtained from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) data set. The correlations between LKB1 expression, clinicopathologic factors, and patient outcome were analyzed. LKB1 expression was significantly associated with estrogen receptor (ER) expression in 2 of the 4 cohorts, but not with other clinicopathologic factors. LKB1 expression was not a predictor for relapse-free survival, overall survival (OS), or breast cancer-specific survival. In a subgroup analysis of the two Taiwanese cohorts, high LKB1 protein expression was predictive of high OS in human epidermal growth factor receptor 2 (HER2)-positive breast cancer patients (P = 0.013). Our study results indicate that LKB1 expression is not prognostic in the whole population of breast cancer patients, but it is a potential predictor of OS in the subset of HER2-positive patients.
authors.affiliation: Department of Oncology, National Taiwan University Hospital.|Graduate Institute of Oncology, National Taiwan University.
authors.forename: I-Chun
authors.initials: IC
authors.lastname: Chen
authors.affiliation: Department of Surgery, Mackay Memorial Hospital.
authors.forename: Yuan-Ching
authors.initials: YC
authors.lastname: Chang
authors.affiliation: Department of Oncology, National Taiwan University Hospital.|Department of Internal Medicine, National Taiwan University Hospital.
authors.forename: Yen-Shen
authors.initials: YS
authors.lastname: Lu
authors.affiliation: Departent of Laboratory Medicine, National Taiwan University Hospital.
authors.forename: Kuei-Pin
authors.initials: KP
authors.lastname: Chung
authors.affiliation: Department of Surgery, National Taiwan University Hospital.
authors.forename: Chiun-Sheng
authors.initials: CS
authors.lastname: Huang
authors.affiliation: Department of Public Health, National Taiwan University.
authors.forename: Tzu-Pin
authors.initials: TP
authors.lastname: Lu
authors.affiliation: Department of Surgery, National Taiwan University Hospital.
authors.forename: Wen-Hung
authors.initials: WH
authors.lastname: Kuo
authors.affiliation: Department of Surgery, National Taiwan University Hospital.
authors.forename: Ming-Yang
authors.initials: MY
authors.lastname: Wang
authors.affiliation: Department of Pathology, National Taiwan University Hospital.
authors.forename: Kuan-Ting
authors.initials: KT
authors.lastname: Kuo
authors.affiliation: Department of Oncology, National Taiwan University Hospital.|Department of Medical Research, National Taiwan University Hospital.
authors.forename: Pei-Fang
authors.initials: PF
authors.lastname: Wu
authors.affiliation: Department of Oncology, National Taiwan University Hospital.
authors.forename: Tsu-Hsin
authors.initials: TH
authors.lastname: Hsueh
authors.affiliation: Graduate Institute of Life Sciences, National Defense Medical Center, Taipei.|Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.|College of Public Health, China Medical University, Taichung, Taiwan.
authors.forename: Chen-Yang
authors.initials: CY
authors.lastname: Shen
authors.affiliation: Department of Oncology, National Taiwan University Hospital.|Department of Internal Medicine, National Taiwan University Hospital.|Oncology Center, National Taiwan University Hospital Hsin-Chu Branch.
authors.forename: Ching-Hung
authors.initials: CH
authors.lastname: Lin
authors.affiliation: Department of Oncology, National Taiwan University Hospital.|Graduate Institute of Oncology, National Taiwan University.|Department of Internal Medicine, National Taiwan University Hospital.
authors.forename: Ann-Lii
authors.initials: AL
authors.lastname: Cheng
mesh_terms: D000091162:AMP-Activated Protein Kinase Kinases; D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000235:genetics* / Q000473:pathology; D009367:Neoplasm Staging; D011379:Prognosis; D017346:Protein Serine-Threonine Kinases / Q000096:biosynthesis* / Q000235:genetics; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics
chemical_list: D000091162:AMP-Activated Protein Kinase Kinases; D017346:Protein Serine-Threonine Kinases; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human; C109790:STK11 protein, human