p53 protein accumulation and p53 gene alterations (RFLP, VNTR and p53 gene mutations) in non-invasive versus invasive human transitional bladder cancer.

Eleven non-invasive and 24 invasive transitional cell bladder cancers were analysed for molecular alterations to the p53 gene and nuclear accumulation of the p53 protein. 9% (1/11) of non-invasive rumours and 21% (5/24) of invasive tumours revealed nuclear accumulation in more than 50% of the tumour cells. PCR analysis of D17S30 showed loss of heterozygosity (LOH) in invasive tumours (3/24; 12%). Two invasive tumours harboured point mutations in exon 6 and exon 7, respectively (8%). Our results indicate that p53 protein overexpression correlates with tumour progression, p53 gene mutations and LOH detected by PCR.