Caveolin-1 as a promoter of tumour spreading: when, how, where and why

Abstract

Caveolae are non-clathrin invaginations of the plasma membrane in most cell types; they are involved in signalling functions and molecule trafficking, thus modulating several biological functions, including cell growth, apoptosis and angiogenesis. The major structural protein in caveolae is caveolin-1, which is known to act as a key regulator in cancer onset and progression through its role as a tumour suppressor. Caveolin-1 can also promote cell proliferation, survival and metastasis as well as chemo- and radioresistance. Here, we discuss recent findings and novel concepts that support a role for caveolin-1 in cancer development and its distant spreading. We also address the potential application of caveolin-1 in tumour therapy and diagnosis.

Fig. 1

Effects of caveolin-1 activation that promote cancer progression. The left side of the figure shows the Western blot analysis of caveolin-1 expression in a metastatic (WM 266-4) compared with a non-metastatic melanoma cell line (A375; A). On the right of the figure, one case of a primary poorly differentiated lung carcinoma (B: TC scan; D: E&E, 40×; E: Cav1, 40×) and its corresponding brain metastasis (C: TC scan; F: E&E, 40×; G: Cav1, 40×) are reported. The primary lung lesion showed a focal and faint cytoplasmic and membrane Cav1 staining (D and E), whereas in the brain metastasis, (F and G) Cav1 expression was diffuse and intense.