Ikumasa Takenaka

Brain Metastasis from Prostate Cancer: A Case Report

Brain metastases from prostate cancer are rare in postmortem examinations, and even rarer in clinical series. We report an unusual case of brain metastasis from prostate cancer confirmed by antemortem diagnosis in a 72‐year‐old man. The metastatic brain tumor was surgically resected and the patient was kept stable for more than 19 months after diagnosis of the brain metastasis.

Apoptosis and Carcinogenesis: Morphologic Observations in the Rat Bladder Treated with N-Butyl-N-(4-hydroxybutyl)nitrosamine

Background: We investigated the role of apoptosis in rat bladder carcinogenesis induced by N‐butyl‐N‐ (4‐hydroxybutyl)nitrosamine (BBN).

Basement membrane and carcinogenesis : ultrastructural observations in the basement membrane of the bladder epithelium in rats treated with N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN)

This study investigated the structural alterations in the basement membrane (BM) of the bladder epithelium in rats treated with N‐butyl‐N‐(4‐hydroxybutyl)nitrosamine (BBN) using transmission electron microscopy. Following administration of BBN, thickening of the BM of the bladder epithelium was observed and remained almost constant from 4 to 20 weeks, although the pathological changes in the rat bladder epithelium induced by BBN altered over the same period of 20 weeks. The reason for this phenomenon can be explained by the increased interfacial area between the basal epithelial cells and the BM of the rat bladder epithelium due to an increase in the number and size of the microvilli on the basal cell surfaces adjacent to the BM. Our results also showed that the frequency of hemidesmosomes increased progressively during the period of carcinogenesis, especially in the lesions of noninvasive transitional cell carcinoma (TCC) in the rat bladder. It is suggested that the neosynthesis of BM components can be carried out both by benign hyperplastic cells and by noninvasive TCC cells of rat bladder. The alterations in the BM thickness may be affected by the changes in the number and size of the microvilli occurring on the basal cell surfaces adjacent to the BM. Both an increased frequency of hemidesmosomes and the neosynthesis of BM are closely related to cell proliferation during carcinogenesis.

Apoptotic cell death and Smad4 expression in transitional cell carcinoma of the renal pelvis and ureter.

Abstract Purpose: To investigate the frequency of apoptosis and the expression of Smad4 protein as well as their roles in transitional cell carcinoma (TCC) of the renal pelvis and ureter.