Indeed, caveolin-1 expression is reduced in several human tumours, including lung [66, 180, 181], mammary [182], colon [50, 163] and ovarian carcinomas [183] and sarcomas [184], as well as osteosarcomas [185] and re-expression of caveolin-1 often, but not always (see [121, 186–190] and following section) results in reversal of characteristics associated with the transformed phenotype. This evidence concerns the gene CAV1 and osteosarcoma.