Urinary glucuronidase and arylsulfatases in identical twins of bladder cancer patients.

Studies showing that bladder cancer patients have unusually high levels of urinary beta-glucuronidase and arylsulfatases A and B led to the suggestion that these urinary enzymes may participate in bladder cancer etiology. An alternative explanation of the high levels of these urinary enzymes in bladder cancer patients is that the disease itself causes the elevation. Since the levels of these enzymes are genetically determined, measuring these enzymes in healthy identical twins of bladder cancer patients can test whether high enzyme levels occurred prior to bladder cancer. Five healthy identical cotwins of bladder cancer patients, together with matched controls, were measured for urinary beta-glucuronidase, arylsulfatases A and B, and two other lysosomal enzymes as controls, alpha- and beta-galactosidases. The mean levels of all five enzymes were not very different in the cotwins and controls, suggesting that high levels of urinary enzymes observed in bladder cancer patients are a consequence of disease rather than occurring prior to disease and contributing to its etiology.