LENGTH OF TELOMERIC REPEATS IN NEUROBLASTOMA - CORRELATION WITH PROGNOSIS AND OTHER BIOLOGICAL CHARACTERISTICS

Telomeres are the physical ends of eukaryotic chromosomes. In view of reports of the reduction of telomeric repeats in human malignant tumors, we measured the lengths of telomeric repeats in 55 primary neuroblastomas. The average lengths of telomeric repeats in these tumors fell in a wide range (from 1.1 kb to more than 23 kb) relative to those in ganglioneuromas and normal peripheral mononuclear cells. The reduction of telomeric repeats was significantly correlated with advanced stages of tumor development, poor prognosis, and increased S-phase fractions in tumor cells. On the other hand, three cases of Stage IV-S tumors showed the reduction of telomeric repeats and low percentage of S-phase fractions. These Stage IV-S patients had a good prognosis with spontaneous regression of metastatic tumors.