Array-Comparative Genomic Hybridization Reveals Loss of SOCS6 is Associated with Poor Prognosis in Primary Lung Squamous Cell Carcinoma

Primary tumor recurrence occurs commonly after surgical resection of lung squamous cell carcinoma (SCC). The aim of this study was to identify genes involved in recurrence in lung squamous cell carcinoma patients. Array comparative genomic hybridization (aCGH) was performed on DNA extracted from tumour tissue from 62 patients with primary lung squamous cell carcinomas. aCGH data was analysed to identify genes affected by copy number alterations that may be involved in SCC recurrence. Candidate genes were then selected for technical validation based on differential copy number between recurrence and non-recurrence SCC tumour samples. Genes technically validated advanced to tests of biological replication by qPCR using an independent test set of 72 primary lung SCC tumour samples. 18q22.3 loss was identified by aCGH as significantly associated with recurrence (p=0.038). Although aCGH copy number loss associated with recurrence was found for seven genes within 18q22.3, only SOCS6 copy number loss was both technically replicated by qPCR and biologically validated in the test set. DNA copy number profiling using 44K element array comparative genomic hybridization microarrays of 62 primary lung squamous cell carcinomas.