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Migration of endothelial cells induced by vascular endothelial growth factor (VEGF) is a critical step in angiogenesis. Stimulation of motility by growth factors such as VEGF requires interaction with the signal transduction pathways activated by the extracellular matrix (ECM). Here we demonstrate that the Rac GTPase is the critical intersection activated by type 1 collagen ECM and VEGF during stimulation of endothelial cell motility. To analyze the role of the Rho family GTPases in VEGF-stimulated endothelial cell chemotaxis and ECM-stimulated haptotaxis, we transduced the respective fusion proteins in human foreskin dermal endothelial cells using a Tat peptide from the human immunodeficiency virus Tat protein. VEGF signaling required Rac activation during chemotaxis, and Rac and Cdc42 were activated during haptotaxis on type I collagen. Similar to VEGF, Rac activation induced an increase in endothelial cell stress fiber and focal adhesion. Surprisingly, Rho activation was not present in collagen-induced haptotaxis or stimulation of chemotaxis by VEGF, although Rho induced stress fibers and focal adhesions similar to Rac activation. The result of constitutive Rho activation was an inhibition of haptotaxis. Thus, Rac is required and sufficient for the activation of endothelial cell haptotaxis and VEGF-stimulated chemotaxis.

Steroid hormones, especially testosterone, play important roles in the carcinogenesis of prostate cancer, and several studies have reported changes in risk with polymorphisms of genes involved in steroid metabolism. One example is the CYP17 gene, which has a polymorphic T-to-C substitution in the 5'-untranslated region giving rise to A1 (T) and A2 (C) alleles. Steroid 5α-reductase type II (SRD5A2), which converts testosterone to the metabolically more active dihydrotestosterone, exhibits 2 polymorphisms: V89L, which substitutes leucine for valine at codon 89, and A49T, which substitutes threonine for alanine at codon 49. We therefore designed a case-control study of 105 prostate-cancer patients and 210 controls with benign prostatic hyperplasia for the purpose of investigating the association between prostate-cancer risk and polymorphisms in the SRD5A2 and CYP17 genes among the Japanese. The frequency of the CYP17 A2/A2 genotype in cases (18.8%) was higher than in controls (14.5%). Compared with the A1/A1 genotype, the odds ratio for the A2/A2 genotype was 2.39 (95% confidence interval 1.04–5.46, p = 0.04). The frequency of the SRD5A2 LL genotype in cases (29.3%) was also slightly higher than in controls (24.6%), but this was not significant. Regarding the A49T polymorphism of SRD5A2, we could not detect the T allele in any of the examined samples. These data suggest a significant association between the CYP17 polymorphism and prostate-cancer risk among the Japanese. © 2001 Wiley-Liss, Inc.

During angiogenesis endothelial cells migrate towards a chemotactic stimulus. Understanding the mechanism of endothelial cell migration is critical to the therapeutic manipulation of angiogenesis and ultimately cancer prevention. Vascular endothelial growth factor (VEGF) is a potent chemotactic stimulus of endothelial cells during angiogenesis. The endothelial cell signal transduction pathway of VEGF represents a potential target for cancer therapy, but the mechanisms of post-receptor signal transduction including the roles of rho family GTPases in regulating the cytoskeletal effects of VEGF in endothelial cells are not understood.Here we analyze the mechanisms of cell migration in the mouse brain endothelial cell line (bEND3). Stable transfectants containing a tetracycline repressible expression vector were used to induce expression of Rac mutants. Endothelial cell haptotaxis was stimulated by constitutively active V12Rac on collagen and vitronectin coated supports, and chemotaxis was further stimulated by VEGF. Osteopontin coated supports were the most stimulatory to bEND3 haptotaxis, but VEGF was not effective in further increasing migration on osteopontin coated supports. Haptotaxis on support coated with collagen, vitronectin, and to a lesser degree osteopontin was inhibited by N17 Rac. N17 Rac expression blocked stimulation of endothelial cell chemotaxis by VEGF. As part of the chemotactic stimulation, VEGF caused a loss of actin organization at areas of cell-cell contact and increased stress fiber expression in endothelial cells which were directed towards pores in the transwell membrane. N17 Rac prevented the stimulation of cell-cell contact disruption and the stress fiber stimulation by VEGF.These data demonstrate two pathways of regulating endothelial cell motility, one in which Rac is activated by matrix/integrin stimulation and is a crucial modulator of endothelial cell haptotaxis. The other pathway, in the presence of osteopontin, is Rac independent. VEGF stimulated chemotaxis, is critically dependent on Rac activation. Osteopontin was a potent matrix activator of motility, and perhaps one explanation for the absence of a VEGF plus osteopontin effect is that osteopontin stimulated motility was inhibitory to the Rac pathway.

Protein C inhibitor (PCI) is the plasma serine protease inhibitor of activated protein C, the active enzyme of the anticoagulant protein C pathway. Recently, PCI was also detected in human seminal plasma and reproductive organs (testis, seminal vesicle and prostate) suggesting that PCI may also play an important role in the reproductive system. In this study, we cloned the full length of rat PCI cDNA, and determined its amino acid sequence and tissue distribution. We also evaluated the effect of androgen on PCI mRNA expression in seminal vesicles and testes. The isolated 2074‐bp rat PCI cDNA was composed of a 47‐bp 5′‐non‐coding region, a 1218‐bp coding region of a 406‐amino acid precursor protein, a stop codon and a 806‐bp 3′‐non‐coding region. The deduced amino acid sequence of rat PCI showed 85.7%, 64.1% and 62.2% homology with that of mouse, rhesus monkey and human PCIs, respectively. Northern blot analysis showed that the rat PCI mRNA is expressed strongly in the seminal vesicle, moderately in the testis, but not in the liver. PCI mRNA expression in seminal vesicles and testes was found to increase during the process of development, suggesting that it is under androgen control. Subsequently, we examined the effect of castration and/or treatment with 17β‐estradiol or testosterone on PCI mRNA expression in the mature rat seminal vesicles. The PCI mRNA expression in seminal vesicles was significantly decreased after castration or 17β‐estradiol treatment. Testosterone itself did not affect PCI mRNA expression, but treatment in castrated rats significantly enhanced its mRNA expression. These findings suggest that the PCI gene expression in rat seminal vesicles is regulated by androgen.

99mTechnetium dimercaptosuccinic acid renal scintigraphy, consisting of the cortical image and dimercaptosuccinic acid renal uptake rate, was used to assess preoperative and postoperative renal function in 55 patients with staghorn calculi. In 14 of 20 patients who had undergone extended pyelolithotomy and in 4 of 22 who had undergone nephrolithotomy there was an increase or no change in the postoperative dimercaptosuccinic acid renal uptake in the surgically treated kidney. However, there was no increase in the postoperative dimercaptosuccinic acid renal uptake in the patients who had undergone pyelolithotomy combined with nephrotomy or partial nephrectomy. Eight per cent of the preoperative dimercaptosuccinic acid renal uptake rate in the diseased kidney seems to be the absolute level for predicting the postoperative recovery of renal function. Dimercaptosuccinic acid renal images provide evidence of morphological changes in the cortex of the kidney with stones and the dimercaptosuccinic acid uptake rate is a useful adjunct for quantitative assessments of preoperative and postoperative residual cortical function.

Background:

Background:The p53mutation spectrum of prostate cancers developing in Japan indicates a role for environmental factors. This suggests there might be differences in susceptibility due to genetic polymorphisms in metabolic activation enzyme genes. We analyzed genetic polymorphisms of the xenobiotic-metabolizing enzymes, CYP1A1 and GSTM1.Method:Genotyping of CYP1A1and GSTM1was investigated by using allele-specific PCR in 115 prostate cancer (PCa) patients and 204 control patients.Results:The CYP1A1 Val/Valgenotype significantly increased the risk for PCa (OR = 2.6; 95% CI = 1.11–6.25) and the Ile/Valgenotype showed a similar tendency (OR = 1.4; CI = 0.86–2.29). Individuals with the GSTM1 (0/0)genotype demonstrated a slightly increased risk (OR = 1.3; CI = 0.82–2.04). The combination of the CYP1A1 Valallele and GSTM1(010) genotype was associated with a higher risk (OR = 2.3; CI = 1.18–4.48) than the CYP1A1Val allele alone. When cases were analyzed by age at initial diagnosis, the relative risks with both the CYP1A1Val allele and the GSTM1(0/0) genotype were higher in the young group than in the old group (CYP1A1; OR = 1.7, CI = 0.89–3.17: GSTM1; OR = 1.6, CI = 0.84–2.99). The frequency of the GSTM1(0/0) genotype was also higher in patients with advanced stage disease. In stage D, the OR was 1.7 with a CI of 0.93–3.17 and in stages A and B, the OR was 0.8 with a CI of 0.40–1.62.Conclusions:These results suggest that CYP1A1and GSTM1polymorphisms are linked to a propensity for PCa development.

Ductal morphogenesis and adult ductal branching patterns were examined in the rat prostate by a microdissection method. The rat prostate consists of paired (right and left) subdivisions which correspond in large part to the classically defined lobes: ventral prostate, lateral prostate, dorsal prostate, and coagulating gland. Of particular interest was the finding that the lateral prostate consists of two different ductal zones: (1) lateral type 1 prostate with 5–7 long main ducts (resembling miniature palm trees) that extend cranially towards both the seminal vesicle and dorsal prostate to arborize near the bladder neck, and (2) lateral type 2 prostate with 5–6 short main ducts that arborize caudal to the bladder neck and give rise to compact bushy glands. Both lateral prostatic groups had a ductal-acinar organization. The adult structure of the other rat prostatic lobes was also examined, and closely resembled their mouse counterparts. The ventral prostate, which had 2–3 pairs of slender main ducts per side, and the coagulating gland, which had 1 main duct per side, was completely ductal in structure. In contrast, the dorsal prostate, which had 5–6 pairs of main ducts per side, had a ductal-acinar structure. Ductal branching morphogenesis occurred at different rates in different lobes and was essentially complete in the prostate at the 30 days.Immunocytochemical studies with an antibody to DP-1, a major secretory protein of the rat dorsal prostate, revealed that secretory function was initiated at approximately 30 days after birth in the coagulating gland, the dorsal prostate, and lateral type 1 prostate. A consistent feature of the lateral type 2 prostate was the absence of DP-1. On Western blots, DP-1 was detected in the secretion of the coagulating gland, lateral type 1 and dorsal prostate, but not in the ventral and lateral type 2 prostate. Polyacrylamide gel electrophoresis confirmed this result and demonstrated that the lateral type 2 prostate expressed several low-molecular weight secretory proteins not found in the other lobes of the prostate. On the whole, the rat prostate exhibited considerable heterogeneity both between and within lobes in developmental processes, ductal patterning, histology, and functional expression.

Abstract: Background: Although radical nephrectomy is the standard treatment for renal cell carcinoma, nephron-sparing surgery is the preferred treatment in patients with a single functioning kidney. It is important before surgery to evaluate the level of residual renal function likely after the operation. In this study, we investigated the prediction of residual renal function, using technetium Tc 99m dimercaptosuccinic acid (99mTc-DMSA) renal scintigraphy, before nephron-sparing surgery for renal tumors. Methods: Preoperative and postoperative evaluation of renal function was done in 11 patients with renal cell carcinoma or renal angiomyolipoma, using99mTc-DMSA scintigraphy. Nine patients had renal cell carcinoma and 2 had renal angiomyolipoma. Partial nephrectomy was performed in 4 patients and surgical enucleation in 7 patients. Both the predicted total DMSA renal uptake rate prior to surgery and the actual postoperative total99mTc-DMSA renal uptake rate were obtained. Endogenous creatinine clearance and serum creatinine levels were also obtained. Results: There was a good relationship between the predicted and postoperative total99mTc-DMSA renal uptake rates. The ratio of the postoperative total DMSA renal uptake rate to the predicted total99mTc-DMSA renal uptake rate was 85% after partial nephrectomy, and 101% after surgical enucleation. There was also a significant correlation between the postoperative total99mTc-DMSA renal uptake rate and creatinine clearance, and postoperative total99mTc-DMSA renal uptake rate levels above 11.4% coincided with serum creatinine levels below 2.0 mg/dL. Conclusion: Preoperative assessment with99mTc-DMSA renal scintigraphy is clinically useful for predicting residual renal function after nephron-sparing surgery.

The relationship between glo-merular filtration rate and tubular glucose reabsorption was examined in rats with experimental glomerulonephritis. Glomerular filtration rates (single kidney) varied from 0.09 to 0.95 ml/min and superficial nephron filtration rates ranged from 4.4 to 38.2 nl/ min. A direct linear relationship between filtration rate and maximal glucose reabsorption rates was observed in individual superficial nephrons as well as in the whole kidney. Changes in peritubular oncotic pressure and extracellular fluid volume modified glucose reabsorptive rates, but the linear relationship between filtration rate and glucose reabsorption persisted. These data support the thesis that glomerulo-tubular balance for glucose is a characteristic feature of renal glucose transport.The studies referred to in this manuscript were supported by Public Health Service Grant No. T501 HL06008. We are also grateful to Dr. Oliver H.Lowry and Ms. Margaret Philips for performing the microenzymatic glucose determinations.

99mTc dimercaptosuccinic acid is a new renal scanning agent that provides a good quality of renal image as a result of preferential cortical accumulation and also makes feasible a quantitative assessment of separate kidney function, correlating well with renal plasma flow obtained from a 131I hippuran renogram of each kidney. By measuring the dimercaptosuccinic acid uptake, the cortical functioning nephrons can be determined independent of the activity from the urinary outflow tract. Such evaluations may replace the conventional split renal function study in which traumatic procedures, such as cystoscopy and ureteral catheterizations, are required. 99mTc dimercaptosuccinic acid scintigraphy causes less discomfort to the patient and can be performed repeatedly and routinely even in children and debilitated geriatric patients.

The in vivo renal volume was determined using SPECT for 99mTc-DMSA renal imaging. The total renal volume was derived by summing the DMSA distribution volumes of the transaxial slices in the whole kidney. In 20 healthy subjects the renal volume in the right kidney was 220 ml for men and 195.2 ml for women, while that in the left kidney was 213 ml for men and 193.7 ml for women. Differences in those values were not statistically significant. A good correlation was found between renal volumes in both kidneys and body surface area. In 106 kidneys including solitary and pathological kidneys, individual renal volume correlated well with individual DMSA renal uptake rate which demonstrates cortical functioning mass, depending on the cortical blood flow. Thus, SPECT enables an accurate noninvasive means of estimating in vivo functioning renal volume.

A case of choriocarcinoma and undifferentiated cell carcinoma of the bladder is reported. Transitional cell carcinoma was found initially in the bladder wall and in the terminal stage there was clinical evidence of production of gonadotropin. The concept of choriocarcinoma mimicry would supplant the explanation for the pathological features in this case.

We describe a male subject with 3 Y chromosomes who presented with complaints of lack of sexual desire and failure to achieve rigid erection. The patient was tall and had markedly incurved little fingers on both hands as well as small testes. Karyotype was 48, XYYY. The patient’s parents had normal karyotypes. Endocrinological profile suggested a primary functional disturbance of the gonads. Testicular biopsy demonstrated atrophic seminiferous tubules without spermatogenesis. To our knowledge this case represents the third instance of a man with an 48, XYYY karyotype without mosaicism.

We report on a patient with renal artery stenosis who had only 1 kidney and in whom acute renal impairment developed with transient anuria after the administration of Captopril. Although inhibition of the angiotensin-converting enzyme is considered to be efficient treatment for hypertension associated with chronic renal failure, care should be taken when Captopril is administered initially to a patient with decreased renal function, under the conditions of sodium and water depletion. The renovascular hypertension in this patient was treated successfully by renal autotransplantation.

We report a case of one of the largest aneurysms ever detected in the renal arteriovenous system. This is the seventeenth such case to be reported.