DETECTION OF p53 AND bcl-2 PROTEIN IN CARCINOMA OF THE RENAL PELVIS AND URETER INCLUDING DYSPLASIA

✍ Scribed by FURIHATA, MUTSUO; SONOBE, HIROSHI; OHTSUKI, YUJI; YAMASHITA, MOTOYUKI; MORIOKA, MASAAKI; YAMAMOTO, AKIHIRO; TERAO, NAOTAMI; KUWAHARA, MORIMASA; FUJISAKI, NOBUTA

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 817 KB
• Volume: 178
• Category: Article
• ISSN: 0022-3417
• DOI: 10.1002/(sici)1096-9896(199602)178:2<133::aid-path455>3.0.co;2-f

✦ Synopsis

Ninety-four patients with transitional cell carcinoma (TCC) of the renal pelvis and ureter, including dysplastic lesions, were studied for p53 and bcl-2 protein expression by immunohistochemistry. Twenty-one patients were also studied for p53 gene mutations by direct sequencing and for bcl-2 gene rearrangement by Southern blot analysis. Overexpressed p53 protein was detected in 26 cases (27.7 per cent). bcl-2 immunostaining was observed in 21 tumours (22.3 per cent), including four cases with labelling for p53. Furthermore, the dysplastic lesions surrounding 19 p53-positive tumours also stained for p53. bcl-2 expression was also detected frequently in dysplastic lesions adjacent to 14 bcl-2-positive TCCs. Positive reactions of dysplastic lesions were also found adjacent to 37 bcl-2-negative tumours. p53 point mutation was detected in 6 of 21 cases. Five of the six cases were positive for p53 protein. bcl-2 positivity was detected in 3 of 21 tumours, without bcl-2 gene rearrangements in the major breakpoint region. Overexpressed p53 protein was frequently detected in both high-grade (P<0.05) and invasive tumours (P<0*05). In three cases of p53-positive non-papillary invasive tumours, bcl-2 was found in non-invasive portions, but was not present in invasive areas. These findings suggest that overexpression (mutation) of p53 andlor bcl-2 protein may be early events in tumourigenesis and that p53 alterations in particular are essential for the maintenance of a malignant phenotype in tumour development.