Hiroshi Tazaki

Role of reactive oxygen species in cis-dichlorodiammineplatinum-induced cytotoxicity on bladder cancer cells.

This study was undertaken to investigate the intracellular induction of reactive oxygen species (ROS) by cis-dichlorodiammineplatinum (CDDP) and the augmentation of their cytotoxicity in bladder cancer cells (KU7) by enhancement of ROS generation by the glutathione (GSH) depletors buthionine sulphoximine (BSO) and diethylmaleate (DEM). CDDP-induced cytotoxicity in KU7 cells and its modulation by GSH depletors were determined using spectrophotometric measurement with crystal violet staining. The effects of GSH depletors on intracellular GSH levels were confirmed using the GSH reductase-DTNB recycling method. Intracellular ROS generation induced by CDDP with or without GSH depletors was estimated from the amount of intracellular dichlorofluorescein (DCF), an oxidized product of dichlorofluorescein (DCFH), which was measured with an anchored cell analysis and sorting system. The cytotoxic effects of CDDP (IC50 15.0 +/- 2.5 microM) were significantly enhanced by BSO (IC50 9.3 +/- 2.6 microM, P < 0.01) and DEM (IC50 10.3 +/- 0.3 microM, P <0.01). BSO and DEM produced a significant depletion in intracellular GSH levels (9.6 +/- 0.4 nmol 10(-6) cells, 17.9 +/- 1.0 nmol 10(-6) cells) compared with the controls (30.5 +/- 0.6 nmol 10(-6) cells). Intracellular DCF production in KU7 cells treated with CDDP (1.35 +/- 0.33 microM) was significantly enhanced by the addition of BSO (4.43 +/- 0.33 microM) or DEM (3.12 +/- 0.22 microM) at 150 min. These results suggest that ROS may play a substantial role in CDDP-induced cytotoxicity and that GSH depletors augment its cytotoxicity through an enhancement of ROS generation in bladder cancer cells.

GLYOXALASE I ACTIVITY IN HUMAN PROSTATE CANCER: A POTENTIAL MARKER AND IMPORTANCE IN CHEMOTHERAPY

PURPOSE To provide information on the activity of Gly-I in prostate cancer. MATERIALS AND METHODS We performed qualitative Gly-I assay on prostate tissues. RESULTS Gly-I activity between prostate cancer and noncancerous specimens differed substantially and significantly, although such activity also varied somewhat among cancer specimens. CONCLUSIONS Gly-I activity is indeed higher in cancerous than in noncancerous specimens, suggesting that it may play a role in prostate cancer homeostasis and survival.

Laparoscopic surgical correction ofcircuivicaval ureter

Laparoscopic transposition and reanastomosis of a circumcaval ureter were performed in a 52-year-old man with right flank pain. A preoperative perfusion pressure study revealed abnormally high intrapelvic pressure. Under laparoscopy, the renal pelvis was divided above the ureteropelvic junction and the ureter was relocated from behind the vena cava. A 5 cm segment of redundant ureter containing the postcaval segment was resected and the ureteral end and renal pelvis were reapproximated with interrupted sutures by intracorporeal knot typing. The postoperative convalescence was uneventful, not necessitating the administration of analgesics. The patient resumed full activities 3 weeks later. The intravenous urogram and renogram obtained 2 months after the operation revealed remarkable improvement in the ureteral obstruction.

Differential Diagnosis of Primary Benign and Malignant Retroperitoneal Tumors

Background:

Efficacy of gadolinium-diethylenetriaminepentaacetic acid-enhanced magnetic resonance imaging for differentiation between superficial and muscle-invasive tumor of the bladder: A comparative study with computerized tomography and transurethral ultrasonography

Gadolinium-labeled diethylenetriaminepentaacetic acid (Gd-DTPA)-enhanced magnetic resonance imaging (MRI) was evaluated in an effort to clarify whether MRI could replace or be proved to be superior to computerized tomography (CT) and/or transurethral ultrasonography. A total of 57 bladder cancer patients was evaluated. MRI was performed with a superconducting magnet operating at 1.5 Tesla. The images acquired were multisections, having a fast spin-echo pulse sequence of less than a 14-second breath holding. Serial scans were performed before and immediately after Gd-DTPA venous injection. The findings on different imaging techniques were compared with the histological stagings. A proper diagnosis was made in 42 of 57 cases (73.7%) by Gd-DTPA-enhanced MRI, in 27 of 57 (47.4%) by CT and in 31 of 57 (54.4%) by transurethral ultrasonography when comparing the histological findings. The sensitivity and specificity for differentiating superficial and muscle-invasive tumor of each imaging method were, respectively, 96.2 and 83.3% in Gd-DTPA-enhanced MRI, 96.0 and 58.3% in CT, and 88.0 and 66.7% in transurethral ultrasonography. These data suggest that the staging of bladder cancer by Gd-DTPA-enhanced MRI appears to be superior and more accurate than the staging obtained by CT and transurethral ultrasonography.

Intrarenal satellites of renal cell carcinoma: Histopathologic manifestation and clinical implication

OBJECTIVES This study was designed to gain more insight into the incidence of satellites of renal cell carcinoma related to the pathologic stage and grade of the primary tumor. METHODS One hundred eight nephrectomized kidneys with renal cell carcinoma were sectioned at 3-mm intervals and inspected microscopically for satellite carcinomas. The number, site, size, and distance of satellite carcinomas found were recorded in relation to the primary carcinoma. RESULTS The overall incidence of satellite carcinoma was 6.5% (7 of 108). The incidence of satellite carcinoma in relation to the pathologic staging of the primary tumor was 7.1% (1 of 14) in pT1, 3.0% (2 of 66) in pT2, and 14.3% (4 of 28) in pT3. The incidence was higher in patients with N1 disease (25%) than in those with NO (5.0%), and higher in M1 disease (25%) than in those in MO (5.77%). There was no relationship between the grade and multicentricity. CONCLUSIONS The incidence of satellite carcinoma was higher in cases with high-stage primary carcinoma. However, even in localized diseases (PT1, pT2), satellite carcinomas were found at at 3.75% incidence. When nephron-sparing surgery is indicated in low-stage cases, precise clinical staging using a combination of various imaging modalities is mandatory, with intraoperative ultrasonography being one possible modality for detecting a concomitant satellite carcinoma.

Screening of H-ras gene point mutations in 50 cases of bladder carcinoma

Background Mutation converts the H‐ras gene into an activated oncogene in about 10% of human bladder cancers. Codons 12 and 61 are the major “hot spots” for activation. A simple and accurate method to detect point mutations in these codons may be clinically useful for early diagnosis of bladder cancer.

Human lymphoblastoid interferon therapy for advanced renal cell carcinoma

Antitumor activity of human lymphoblastoid interferon (HLBI) in advanced renal cell carcinoma was studied. Intramuscular injection at a dose of 3 X 10(6) IU was given daily to 18 patients, including 14 patients who had undergone nephrectomy and 4 patients who had not undergone the procedure. One patient (5.6%) showed complete remission; 2 patients (11.1%) minor remission, 8 patients (44.4%) stable disease, and 7 patients (38.9%) progression. Three responders were the patients who had had nephrectomy, and whose metastatic sites were lung. Tumor responses were observed in patients with renal cell carcinoma of clear cell type or mixed type of clear cells and granular cells. We concluded that interferon has a potential antitumor activity in selected patients with advanced renal cell carcinoma.

Transplantation of Human Renal Cell Carcinoma to the Nude Mice: As an Intermediate of in Vivo and in Vitro Studies

Five human renal cell carcinomas were transplanted successfully to nude mice fed and grown under a specific pathogen-free condition. The histology of the transplanted tumor tissue was a close reproduction of the original human cancer tissue in situ. The transplanted tumor tissue possessed an abundant supply of blood vessels, which was considered to be of host animal origin. All transplanted tumor cells grew easily when transferred to an in vitro cell culture system from the nude mice. In this latter cell culture system tumor cells demonstrated a growth pattern characteristic of epithelial cells. The electron microscopy of these cells showed some characteristic morphological features that indicated their cytological origin.

Myelolipoma of the Adrenal Gland

A case is reported of an adrenal myelolipoma producing a retroperitoneal hematoma. A right suprarenal mass with fatty density was detected by a computerized tomography scan. The mass had irregular vessels on the arteriogram. This is the youngest patient reported among those with surgically removed myelolipoma. There was no endocrine activity.