Roles of the transforming growth factor β1 and its type I and II receptors in the development of a pulmonary adenocarcinoma: Results of an immunohistochemical study

BACKGROUND: In the United States, pulmonary adenocarcinomas have recently replaced squamous cell carcinomas as the most frequent type of lung cancer encountered. The incidence of pulmonary adenocarcinoma continued to increase worldwide. METHOD: To determine the roles of the transforming growth factor-beta 1 (TGF-beta 1), and TGF-beta type I receptor (T beta R-I), and the TGF-beta type II receptor (T beta R-II) in the progression of a pulmonary adenocarcinoma, their respective expressions have been immunohistologically studied in specimens from 120 pulmonary adenocarcinoma patients. RESULT: The overall prognosis was significantly poorer for patients showing positive TGF-beta 1, T beta R-I, T beta R-II expressions than for patients who were negative to all three immunostainings (P < 0.01). Our multivariate analysis also revealed that a positive TGF-beta 1 response significantly affect prognosis (P < 0.05). CONCLUSIONS: TGF-beta 1, T beta R-I, and T beta R-II play important roles in tumor progression, and a positive TGF-beta 1 expression can serve as a pulmonary adenocarcinoma marker. T beta R-I and T beta R-II expressions are necessary for TGF-beta signal transduction.