Telomerase activity and telomere lengths: alterations in renal cell carcinomas.

Detection of telomerase activity in renal cell carcinomas may be a key to understanding the loss of growth control in tumor cells. This enzyme forms the end of most chromosomal DNAs (that is, telomeres) found in renal tumors. When activated, the telomeres shorten with every cell cycle and then there is a compensatory lengthening of the cells, which then proliferate and eventually become immortal and metastasize. This complex multigenetic process may prove to be a useful marker of tumor progression and patient outcome.