title: Detection of ALK protein expression in lung squamous cell carcinomas by immunohistochemistry.
abstract: BACKGROUND
  The echinoderm microtubule-associated protein-like 4 (EML4) gene and the anaplastic lymphoma kinase (ALK) gene rearrangements occur in approximately 5% of lung adenocarcimomas (ACA), leading to ALK overexpression and predicting response to targeted therapy. To the present, few studies have been focused on the expression of ALK protein in lung squamous cell carcinomas (SqCC). Only several cases of lung SqCC were reported expression of ALK protein. No clinical study has been published to explicit the relationship between ALK expression and the response to targeted therapy in SqCC.
  
  
  METHODS
  In this study, we analyzed ALK protein expression with a specific rabbit monoclonal Ig antibody (D5F3 clone) in 207 cases of lung SqCC. The positive cases were confirmed with ALK fluorescence in situ hybridization (FISH) and RT-PCR.
  
  
  RESULTS
  We found that 3 out of 207 (1.4%) cases of lung SqCC were ALK positive detected by IHC staining, which were confirmed by ALK FISH and RT-PCR.
  
  
  CONCLUSIONS
  Our results indicate that ALK protein expression is not a rare molecular event in SqCC. Although the frequency of EML4-ALK rearrangements is lower in lung SqCC than that in lung adenocarcinomas, their presence may provide additional treatment options in lung SqCC. The response of SqCC patients with ALK expression to target therapy of crizotinib should be explored.
authors.affiliation: Department of Pathology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China. jd_wang@outlook.com.
authors.forename: Jiandong
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Pathology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China. jd_wang@outlook.com.
authors.forename: Qin
authors.initials: Q
authors.lastname: Shen
authors.affiliation: Department of Pathology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China. shiqunli2005@aliyun.com.
authors.forename: Qunli
authors.initials: Q
authors.lastname: Shi
authors.affiliation: Department of Pathology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China. 9441698@qq.com.
authors.forename: Bo
authors.initials: B
authors.lastname: Yu
authors.affiliation: Department of Pathology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China. wangxuan1130@163.com.
authors.forename: Xuan
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Pathology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China. chengkai_seu@126.com.
authors.forename: Kai
authors.initials: K
authors.lastname: Cheng
authors.affiliation: Department of Radiology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China. cjr.luguangming@vip.163.com.
authors.forename: Guangming
authors.initials: G
authors.lastname: Lu
authors.affiliation: Department of Pathology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China. nanjing_81@yahoo.com.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Zhou
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000077548:Anaplastic Lymphoma Kinase; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000235:genetics; D002294:Carcinoma, Squamous Cell / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D005260:Female; D015321:Gene Rearrangement; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008175:Lung Neoplasms / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015514:Oncogene Proteins, Fusion / Q000235:genetics; D020794:Receptor Protein-Tyrosine Kinases / Q000032:analysis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D014408:Biomarkers, Tumor; C522504:EML4-ALK fusion protein, human; D015514:Oncogene Proteins, Fusion; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D020794:Receptor Protein-Tyrosine Kinases