Gene therapy strategies based on modifying tumour cells using high efficiency adenoviral vectors have shown promise in the clinic. Recently the Coxsackie and adenovirus receptor (CAR) has been shown to mediate adenoviral entry into tumour cells, although previous studies also suggested a role for MHC class I heavy chain. Detailed evaluation of the expression of both CAR and MHC class I in prostate cancer cell lines would have important implications for therapeutic strategies. We have found that, unlike cell lines derived from other malignancies, in human and murine prostate cancer loss of CAR expression appears to be relatively infrequent and does not correlate with loss of MHC class I expression. These findings, together with the demonstration of appreciable levels of cell-surface expression of integrins, suggest that cancer vaccine strategies based on modifying whole prostate cancer cells should be feasible using the current generation of recombinant adenoviral vectors, without deleterious effects on either the virus vector or the target cell.