Frequent expression of Bcl-2 in renal-cell carcinomas carrying wild-type p53.
The p53 tumor-suppressor gene is the most commonly mutated gene in cancer. However, p53 gene alterations are infrequent in renal-cell cancer (RCC). Bcl-2 has been shown to inhibit apoptosis triggered by wild-type p53 and an inverse correlation between Bcl-2 expression and p53 mutation has been observed in breast cancer and glioma. To characterize the expression of bcl-2 in RCC and its relationship to the p53 status, we analyzed 25 RCCs by immunohistochemistry for Bcl-2 and p53, Southern hybridization for bcl-2, and PCR-SSCP and sequencing for p53. Positive Bcl-2 staining was detected in 17 of 25 RCCs, whereas positive p53 staining was seen in only 1. Amplification of bcl-2 or p53 mutation was not detected in any of the tumors. Bcl-2 protein was expressed in all 7 RCC cell lines examined. Only one of the 7 lines had p53 mutation. These results suggest that overexpression of bcl-2, rather than p53 mutation, may prevent apoptosis during RCC development.
Tomita
Y
Y
Department of Urology, Niigata University School of Medicine, Japan.
Bilim
V
V
Kawasaki
T
T
Takahashi
K
K
Okan
I
I
Magnusson
K P
KP
Wiman
K G
KG
D017209:Apoptosis; D002292:Carcinoma, Renal Cell / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D002460:Cell Line; D016158:Genes, p53; D006801:Humans; D007124:Immunoenzyme Techniques; D007668:Kidney / Q000378:metabolism; D007680:Kidney Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis* / Q000235:genetics; D019253:Proto-Oncogene Proteins c-bcl-2; D011519:Proto-Oncogenes; D012016:Reference Values; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000032:analysis*
D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53