Genetic alteration profiling of patients with resected squamous cell lung carcinomas

Abstract

In this study, we analyzed the genetic profiles of squamous cell lung carcinoma (SqCLC) to identify potential therapeutic targets. Approximately 2,800 COSMIC mutations from 50 genes were determined by next-generation sequencing. Amplification/deletion of SOX2, CDKN2A, PTEN, FGFR1, EGFR, CCND1, HER2 and PDGFRA were detected by FISH and expression of VEGFR2, PD-L1 and PTEN were examined by IHC. One hundred and fifty-seven samples of SqCLC were collected. Somatic mutations was identified in 73.9% of cases, with TP53 (56.1%), CDKN2A (8.9%), PIK3CA (8.9%), KRAS (4.5%) and EGFR (3.2%). Gene copy number alterations were identified in 75.8% of cases, including SOX2 amplification (31.2%), CDKN2A deletion (21.7%), PTEN deletion (16.6%), FGFR1 amplification (15.9%), EGFR amplification (14.0%), CCND1 amplification (14.0%), HER2 amplification (9.6%) and PDGFRA amplification (7.6%). Positive expression of VEGFR2 and PD-L1 and loss of PTEN expression were observed in 80.5%, 47.2%, and 42.7% of cases, respectively. Multivariate analysis showed that positive expression of PD-L1 was an independent favorable prognostic factor for DFS (HR = 0.610; P = 0.044). In conclusion, nearly all (93.6%) SqCLC cases harbored at least one potential druggable target. The findings of this study could facilitate the identification of therapeutic target candidates for precision medicine of SqCLC.