Telomerase activity in central nervous system malignant lymphoma

BACKGROUND, Primary central nervous system malignant lymphoma (PCNSL) has b een regarded as a rare neoplasm. Recently, however, its incidence has been rapidly increasing. Despite active clinical trials, its clinical and biolog ic features remain unknown and there has been no effective treatment or pro gnostic factor. The current study attempted to elucidate telomerase activit y and expression of the telomere-related RNA of PCNSL as novel prognostic f actors. METHODS. The subjects were 12 patients with histologically diagnosed PCNSL. All patients were treated with chemoradiotherapy consisting of whole-brain radiation, vincristine, etoposide, and prednisolone. Telomerase activity i n the resected tumor was analyzed both qualitatively and quantitatively usi ng the TRAP (telomeric amplification assay protocol) /TRAP-HPA (hybridizati on protection assay) method. The expression of telomere-related RNA (hTERT, hTERC, and TEP1) was analyzed by reverse transcriptase-polymerase chain re action. RESULTS. Telomerase activity was detected in 10 of 12 patients with PCNSL, with an average activity of 148.9 relative light units. The average telomer e length was 5.55 kb. The expression of hTERT correlated with telomerase ac tivity, and there was a statistically significant correlation between telom erase activity and both the duration of survival and the interval to tumor progression. CONCLUSIONS. Telomerase activity and the expression of hTERT may be novel p rognostic factors in patients with PCNSL. (C) 1999 American Cancer Society.