Difference of caveolin-1 expression pattern in human lung neoplastic tissue. Atypical adenomatous hyperplasia, adenocarcinoma and squamous cell carcinoma

Caveolin-1 has been implicated in cellular transformation and tumorigenesis. We assessed lung cancer specimens for caveolin-1 expression immunohistochemistry. A majority of the cell types in the lung and the bronchial epithelium normally exhibited positive staining for caveolin-1. In adenocarcinomas (ADs) of positive staining for caveolin-1, pT1 tumors exhibited significantly higher staining than pT2–pT4 tumors (P=0.0240). In squamous cell carcinomas (SCCs), pT1–pT2 tumors expressed significantly lower expression levels than pT3–pT4 tumors (P=0.0175). In AD, loss of caveolin-1 may be essential for tumor extension and dedifferentiation. In contrast, caveolin-1 overexpression may be correlated with tumor extension in SCC.