Hioki T

Aminopeptidase N regulated by zinc in human prostate participates in tumor cell invasion

Aminopeptidase N (AP‐N) degrades collagen type IV and is proposed to play a role in tumor invasion. However, the precise functions of AP‐N in tumor cells and the relationship of AP‐N to prostate cancer remains unclear. In our study, we examined a possible role for zinc in the regulation of AP‐N enzymatic activity in relation to tumor cell invasion in human prostate. AP‐N purified from human prostate was irreversibly inhibited by low concentrations of zinc (Ki = 11.2 μM) and bestatin. AP‐N, which has zinc in the active center, was also inhibited by the chelating agents, EDTA, o‐phenanthroline and EGTA. EDTA was shown to remove zinc from the enzyme. When the effects of zinc and bestatin on invasion of PC‐3 cells were investigated in vitro using a Transwell cell‐culture chamber, zinc and bestatin effectively suppressed cell invasion into Matrigel at the concentration range of 50–100 μM. These results strongly suggest that the suppression of PC‐3 cell invasion by zinc is based on the inhibition of AP‐N activity by zinc. We also evaluated the expression of AP‐N to investigate the relationship with the progression of prostate disease in human cancerous prostate. AP‐N was found to be located at the cytoplasmic membranes of prostate gland epithelial cells and to be expressed more in prostate cancer, while the expression of prostate‐specific antigen (PSA), which is a useful marker for prostate cancer, was shown in normal and cancer tissues, suggesting that AP‐N is potentially a good histological marker of prostate cancer. Thus, highly expressed AP‐N in human cancerous prostate probably plays an important role in the invasion and metastasis of prostate cancer cells.

REAL TIME REVERSE TRANSCRIPTASE POLYMERASE CHAIN REACTION OF URINARY CYTOKERATIN 20 DETECTS TRANSITIONAL CELL CARCINOMA CELLS

PURPOSE We evaluate the diagnostic use of cytokeratin 20 messenger (m) RNA quantitation in urine as a marker of urothelial transitional cell carcinoma using the real time reverse transcriptase polymerase chain reaction (RT-PCR). MATERIALS AND METHODS Spontaneously voided urine was obtained from 47 patients with urothelial transitional cell carcinoma (carcinoma group), 19 other urological diseases (noncarcinoma group) and 27 healthy volunteers (control group). Quantification of cytokeratin 20 was performed with mRNA extracted from urine samples with primers and hybridization probes specific for cytokeratin 20 on a LightCycler instrument (Roche Diagnostics Corp., Indianapolis, Indiana). RESULTS This method allowed reproducible quantitation of 10 to 106 cytokeratin 20 expressing colon carcinoma cells per 107 peripheral blood leukocytes, comparable to the sensitivity of conventional RT-PCR with a wide linear measuring range. Cytokeratin 20 mRNA values in the carcinoma group (mean 35,850) were significantly higher than noncarcinoma (171) and control groups (4.55, p <0.0001 and <0.0001, respectively). Urinary cytokeratin 20 mRNA values significantly correlated with tumor grade, urinary cytological class, immunostaining pattern and depth of tumor invasion. Sensitivity and specificity of real time RT-PCR with a cutoff value of 15 were 81% and 83%, whereas those of conventional cytology were 28% and 100%, respectively. CONCLUSIONS These results indicate that real time cytokeratin 20 RT-PCR is a sensitive, quantitative, rapid and specific method to detect free cancer cells in the urine, with good potential for monitoring recurrence of urothelial transitional cell carcinoma.

Ureteroarterial fistula controlled by intraluminal ureteral occlusion

Abstract A 73‐year‐old woman underwent a pelvic exenteration for transitional cell carcinoma of the bladder and radiation‐induced rectovaginal fistula. The patient had undergone radical hysterectomy and radiotherapy for cervical cancer 30 years earlier. Fifteen months after the operation, she suffered from ureteroaortic fistula, which was controlled by intraluminal ureteral occlusion using Gianturco coils. During 53 months of follow up, she has been free of hemorrhagic episodes.

An anterior urethral stitch improves urinary incontinence following radical prostatectomy

Objective: To determine the effects of an anterior urethral stitch, referred to as an endopelvic anterior urethral stitch (EAUS), in reducing recovery time for post‐prostatectomy urinary incontinence.

Stereologically estimated mean nuclear volume of prostatic cancer is a reliable prognostic parameter

Although different histological grading systems of prostatic cancer refer to well-described characteristics, results are hard to reproduce. The aim of this study was to obtain morphometric data that would enable objective and reproducible grading of prostatic cancers by stereological estimation of mean nuclear volume (MNV). The clinical records and tissue specimens from 100 patients who were newly diagnosed as having prostatic cancer from 1973 to 1990 and who were followed up for 5 years or longer were retrospectively examined. We analysed the relationship between MNV and clinical stage, Gleason score and histological grading according to the World Health Organization (WHO) classification. To evaluate prognostic predictors, a multivariate analysis of factors associated with cause-specific survival was performed. We found a good correlation between the MNV and clinical stage and between the MNV and histological grading. There was no correlation between MNVs and Gleason scores. Multivariate analysis revealed that the MNV was the only predictor of survival time (coefficient 0.005; P < 0.0001; hazard ratio 1.005). We consider that the MNV is an excellent predictor of the prognosis in patients with prostatic cancer. Moreover, stereological estimation of MNV is a simple, quick, inexpensive and reliable morphometric procedure that enables the quantitative analysis of the histological and biological character of prostatic cancer.

Preoperative predictors of cancerous involvement of the neurovascular bundles in patients with localized prostate cancer

Abstract Background: The purpose of this study was to identify preoperative variables that would be useful in objectively selecting prostate cancer patients for nerve‐sparing prostatectomy.

[Kinetics of peripheral blood CD34-positive cells and the optimum timing for harvesting peripheral blood stem cells during BEP chemotherapy in patients with testicular germ cell tumor].

PURPOSE Recently, high-dose chemotherapy with peripheral blood stem cell (PBSC) rescue has been developed for poor risk testicular germ cell cancer. In this study, we investigated the optimum timing for harvesting PBSCs with the use of bleomycin + etoposide + cisplatin (BEP) chemotherapy, which is a well known first-line regimen for the testicular cancer. MATERIAL AND METHOD Peripheral blood CD34-positive cell ratios were measured during a total of 10 courses of BEP chemotherapy in 6 patients with metastatic germ cell cancer between 1996 and 1998. We performed 4 apheresis in 3 patients during this period. Recombinant human granulocyte-colony stimulating factor (rhG-CSF) was administrated from the day on which the neutrophil count decreased less than 1,000/microliter. RESULTS The peripheral blood CD34-positive cell ratios became maximum (3.0-24.6%; average 10.0%) on the day 18 to 21 (median day 19) of BEP chemotherapy with rhG-CSF administration. The maximum ratios of peripheral blood CD34 positive cells were achieved when the number of leukocyte were 6,880-23,600/microliter and exceeded 6,000/microliter after the 18th day of BEP chemotherapy. The average number of collected CD34 positive cells was 9.5 x 10(6)/kg at a single apheresis, and 12.6 x 10(6)/kg per patient. CONCLUSION Efficient hematopoietic progenitor cells were mobilized by BEP chemotherapy with rhG-CSF administration of first-line setting. Our results suggest that the optimum timing of PBSCs harvest is the day when the numbers of leukocyte exceed 6,000/microliter after the 18th day of BEP chemotherapy and the following day.