Evaluation of p53, bcl-2 Proteins and DNA Ploidy in Squamous and Transitional Cell Carcinomas of Urinary Bladder

ABSTRACT

The study covered 33 urinary bladder carcinoma cases, where mutated p53 nuclear protein and bcl-2 gene products were evaluated. Image analysis proved the correlation between genopathologic alterations and DNA ploidy. Immunohistochemistiy technique and Feulgen stain methods were applied to paraffin embedded tissue sections. Squamous cell carcinoma [Squ.C.C.] was diagnosed in 19 biopsies and transitional cell carcinoma [T.C.C.] in 14 biopsies. In Squ.C.C group, 10 cases [52.6%] demonstrated nuclear accumulation of mutated p53 protein with significant correlation to the advanced stage and high grade tumors [p=0.03 and 0.0001, respectively]. On the contrary, cytoplasmic expression of bcl-2 was detected in 7 cases [36.8%]. Dual expression of both biomarkers was observed in 2 cases. In T.C.C group, a single case [7.1%] was positive for p53 nuclear reactivity and S cases [35.7%] demonstrated bcl-2 cytoplasmic expression. In both groups, all p53 positive carcinomas comprised significant correlation to aneuploid histograms of DNA distribution patterns. However, 11 out of 12 bcl-2 positive cases [91.6%] demonstrated poliferative diploid histograms with a wide S-phase. It was concluded that, p53 was significantly expressed in Squ C.C. versus T.C.C. and was associated with advanced stage, high grade and aneuploid DNA. On the other hand, bcl-2 expression displayed insignificant difference in both groups of tumor