Background: The signal transducer and activator of transcription 3 (STAT3) play a key role in the downstream pathway of the epidermal growth factor receptor (EGFR) in nonsmall cell lung cancer and promote cell proliferation, invasion, and angiogenesis. The clinical significance of phosphorylated STAT3 (pSTAT3), EGFR, p53, and vascular endothelial growth factor receptor 1 (VEGFR-1) expression in patients with completely resected lung adenocarcinoma was evaluated to determine the effects of pSTAT3 in tumor angiogenesis and proliferation.
Methods: The expressions of pSTAT3, EGFR, p53, and VEGFR-1 were evaluated by immunohistochemical staining of tissue microarrays from 162 samples of resected lung adenocarcinoma.
Results: The median age of the 162 patients was 62 years, the median disease-free survival was 41.7 months, and the median OS (OS) was 80.2 months. Expression of pSTAT3, EGFR, p53, and VEGFR-1 was detected in 51.2%, 71%, 35.2%, and 35.2% of the samples, respectively. pSTAT3 expression was correlated significantly with VEGFR-1 expression (P = .025). The coexpression of pSTAT3 and VEGFR-1 was correlated with increased lymph node involvement (P = .021) and a trend toward a short OS (P = .085). In multivariate analysis, the expression levels of p53 and VEGFR-1 were identified as independent prognostic factors that affected OS.
Conclusions: The results of this study suggested that pSTAT3 and VEGFR-1 expression may play roles in the tumor progression and angiogenesis of lung adenocarcinoma. Further studies are needed, however, to uncover the detailed mechanisms that underlie the roles of these proteins in lung adenocarcinoma.
Copyright 2010 American Cancer Society.