CHROMOSOME-ABERRATIONS IN RENAL TUMORS-DETECTED BY FLUORESCENCE IN-SITU HYBRIDIZATION

The aim of this study was to investigate the relationship between chro mosome aberrations detected by fluorescence in situ hybridization (FIS H) and tumor grade, stage, venous involvement, and DNA ploidy status i n 18 renal tumors. Using FISH with chromosome-specific DNA probes, the copy number of pericentromeric sequences on chromosomes 3, 7, 9, and 1 7 was detected within interphase nuclei in touch preparations from t umor specimens. Monosomy for chromosome 3 was detected in seven of 9 D NA diploid tumors, whereas all DNA aneuploid tumors demonstrated triso my of tetrasomy for chromosome 7. Moreover, monosomy for chromosome 3 was more frequently shown in the diploid and low-stage tumors than in the aneuploid and high-stage tumors. The percentage of hyperdiploid ce lls significantly correlated with DNA ploidy status in the case of chr omosomes 3 and 7 (p = 0.030, p = 0.007, respectively). The percentage of hyperdiploid cells for chromosome 3 had borderline significance wit h tumor stage. On the other hand, the percentage of diploid cells for chromosome 17 was significantly correlated with DNA ploidy status and tumor stage (p = 0.030, p = 0.027, respectively). Moreover, the percen tage of diploid cells for chromosome 7 in renal cell carcinoma (RCC) w ith venous involvement was significantly lower than those without veno us involvement (p = 0.023). These results suggest that the incidence o f chromosomal aberrations detected by FISH is more frequent than the c hromosomal aneuploidy reported previously by conventional cytogenetics . Therefore, loss of chromosome 3 may be associated with an early even t in RCC carcinogenesis. Gain of chromosomes 3 and 7 is correlated wit h tumor progression as well as gain and lass of chromosome 17. Study o f the chromosomal aberrations may provide a greater understanding of t umor carcinogenesis and progression in RCC. (C) Elsevier Science Inc., 1997.