title: MEK5 overexpression is associated with the occurrence and development of colorectal cancer.
abstract: Mitogen/extracellular signal-regulated kinase kinase-5 (MEK5) has been confirmed to play a pivotal role in tumor carcinogenesis and progression. However, few studies have investigated the role of MEK5 in colorectal cancer (CRC).
  
  
  
  MEK5 expression was determined by immunohistochemistry (IHC) in tissue microarrays (TMAs) containing 2 groups of tissues, and western blotting was used to confirm MEK5 expression in 8 cases of primary CRC tissues and paired normal mucosa. RNA interference was used to verify the biological function of MEK5 gene in the development of CRC.
  
  
  
  IHC revealed the expression of MEK5 was higher in tumor tissues (38.1 %), compared with adjacent normal tissue (8.3 %). Western blot showed that, MEK5 expression was upregulated in CRC tumor tissues compared with normal tissue. Analysis of clinical pathology parameters indicated MEK5 overexpression was significantly correlated with the depth of invasion, lymph node metastasis, distant metastasis and histological grade. Survival analysis revealed that MEK5 overexpression negatively correlated with cancer-free survival (hazard ratio 1.64, P = 0.017). RNA interference-mediated knockdown of MEK5 in SW480 colon cancer cells decreased their proliferation, division, migration and invasiveness in vitro and slowed down tumors growth in mice engrafted with the cells.
  
  
  
  MEK5 plays an important role in CRC progression and may be a potential molecular target for the treatment of CRC.
authors.affiliation: Department of Gastrointestinal Surgery, Guangdong Provincal Hospital of Traditional Chinese Medicine, Guangdong, 510120, China. diaodechang@163.com.
authors.forename: Dechang
authors.initials: D
authors.lastname: Diao
authors.affiliation: Institute of Gastroenterology, Sun Yat-Sen University, Guangzhou, 510655, China.|Department of Gastrointestinal Surgery, the Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 510655, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Gastrointestinal Surgery, Guangdong Provincal Hospital of Traditional Chinese Medicine, Guangdong, 510120, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Wan
authors.affiliation: Department of Gastrointestinal Surgery, Guangdong Provincal Hospital of Traditional Chinese Medicine, Guangdong, 510120, China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Gastrointestinal Surgery, the Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 510655, China.
authors.forename: Junsheng
authors.initials: J
authors.lastname: Peng
authors.affiliation: Institute of Gastroenterology, Sun Yat-Sen University, Guangzhou, 510655, China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Ministry of Education, Guangzhou, Guangdong, 510080, China.
authors.forename: Huanliang
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Preventive Medicine and Medical Statistics, College of Fundamental Medical Science, Guangzhou University of Traditional Chinese Medicine, Guangdong, 510006, China.
authors.forename: Xinlin
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Gastrointestinal Surgery, Guangdong Provincal Hospital of Traditional Chinese Medicine, Guangdong, 510120, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of Gastrointestinal Surgery, Guangdong Provincal Hospital of Traditional Chinese Medicine, Guangdong, 510120, China.
authors.forename: Liaonan
authors.initials: L
authors.lastname: Zou
mesh_terms: D045744:Cell Line, Tumor; D049109:Cell Proliferation; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D048671:MAP Kinase Kinase 5 / Q000235:genetics* / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D016019:Survival Analysis; D046888:Tissue Array Analysis / Q000379:methods*; D015854:Up-Regulation
chemical_list: D048671:MAP Kinase Kinase 5; C482563:MAP2K5 protein, human
keywords: Colorectal cancer; MEK5; RNA interference; Tumor growth; Univariate analyses