Abstract

Transitional cell carcinoma of the urinary bladder is the most common cancer of the urinary tract and is characterized by frequent recurrence. Like the other malignant tumor, the genetic alterations leading to neoplastic transformation of the urothelium are related with the activation of oncogenes and loss of functional tumor suppressor genes. Cyclin D1 is a putative protooncogene as cell cycle regulator essential for G1 phase progression and is frequently overexpressed in several human tumor. In this study we performed immunohistochemical stainings of cyclin D1 and p53 in both primary and recurrent transitional cell carcinomas of urinary bladder from 56 patients including 20 cases of recurrent tumor, and compared their results with histopathologic features. The results were as follows. Cyclin D1 immunoreactivity was found in 10 of 10 cases (100%) of grade 1, 25 of 41 (61%) cases of grade 2, and 11 of 25 (44%) cases of grade 3 transitional cell carcinomas. p53 immunoreactivity was found in 40% of grade 1, 63% of grade 2, and 87% of grade 3 lesions. Cyclin D1 expression was significantly higher in Ta and T1 lesions than T2 to T4 by pathologic tumor stage. Conversely p53 immunoreactivity was increased in proportion to the T classification. Cyclin D1 was de creased in recurrent transitional cell carcinomas, compared with primary transitional cell carcinomas. However, there was no statistical significance. In conclusion, cyclin D1 immunoreactivity is associated with low histologic grade and low tumor stage. And there is inverse relationship between the cyclin D1 and p53 overexpression.

• Keywords: Transitional cell carcinoma;Urinary bladder;Cyclin D1;p53;