INCREASED P53 PROTEIN DOES NOT CORRELATE TO P53 GENE-MUTATIONS IN MICRODISSECTED HUMAN TESTICULAR GERM-CELL TUMORS

Purpose: To determine if primary testicular germ cell tumors that over express p53 tumor suppressor gene protein have p53 gene mutations. Mat erials and Methods: We examined 30 primary testicular tissues from 26 patients representing two groups, Group one consisted of eleven cases (6 nonseminomatous germ cell tumors and 5 seminomas) in which tissue s amples for DNA analysis were microdissected from paraffin block region s with elevated immunohistochemical staining for p53 protein, Group tw o consisted of 19 testis tumor tissues which had been fresh frozen and were chosen to correspond to archival tissue specimens exhibiting ele vated levels of p53 protein. The DNA was extracted from these tissues and subjected to exon specific amplification by polymerase chain react ion (PCR) and cold single-strand conformation polymorphism (Cold SSCP) analysis. Results: In these cases with elevated p53 protein, no p53 g ene exon 5-8 mutations were detected except 1 seminoma with a codon 14 0 silent mutation (no protein alteration). Conclusions: Testicular tum ors appear to exhibit elevated levels of wild-type p53 protein, the si gnificance of which is yet to be elucidated.