Metastasis markers in bladder cancer: a review of the literature and clinical considerations.

Cancer invasion and metastasis develop through a sequence of processes involving loss of cell-cell and cell-matrix adhesions, proteolysis and induction of angiogenesis. We reviewed the current literature on the molecules that have been shown to play a significant role in these three steps of metastatisation in bladder cancer (BC) cells and their host microenvironment. Particular emphasis was given to markers that are assessable through immunohistochemistry and for which an additional prognostic value over the TNM variables has been recognized, in order to identify a subset of tumour markers readily available for application in daily clinical practice. We conclude that markers such as E-cadherin, Sialosyl-LeX, laminin, collagen IV, TSP-1 and MVD are useful prognostic markers, alpha, beta, and gamma catenin, MMP-2 and -9, uPAR, PD-ECGF and Bfgf can be considered potentially useful, while research on CD44, MMP-1 and -3, uPA, cathepsin D and VEGF has proved inconclusive. Further research in this field should concentrate on the molecules listed in the first group.