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S Kurimoto

Publications and source records attributed to S Kurimoto.

At least 19 recordsLinked to original sources
PubMed1998

Co-expression of hepatocyte growth factor and its receptor in human prostate cancer.

Hepatocyte growth factor acts differently depending on the organs or tumours involved. It may be produced simultaneously with its receptor, c-Met, in several types of malignant tumour cells and may exercise an autocrine regulation. To analyse the effect of hepatocyte growth factor in human prostate cancer, we conducted immunohistochemistry, in situ hybridization and the reverse transcriptase polymerase chain reaction. The first two techniques revealed the growth factor in prostate cancer cells, and the polymerase chain reaction confirmed this expression. c-Met is expressed in prostate cancer cells, but not in interstitial cells. Hepatocyte growth factor is expressed in interstitial cells, especially in hormone-treated cancer tissue, indicating that the growth factor pathway changes with the hormonal status. Low-grade tumours expressed c-Met at the plasma membrane. Higher grade tumours tended to express it in the cytoplasm, suggesting that the role of c-Met as the hepatocyte growth factor receptor was blocked in higher grade tumours. The relationship between the growth factor and its receptor is thus influenced by hormonal status and differentiation in prostate cancer and is not explained simply in terms of autocrine or paracrine action.

Aged↗
PubMed1998

Evaluation of histological structure and its effect on the distribution of alpha1-adrenoceptors in human benign prostatic hyperplasia.

OBJECTIVE: To evaluate the histological structure of benign prostatic hyperplasia (BPH) and its relationship with the density of alpha1-adrenoceptors in smooth muscle. MATERIALS AND METHODS: Specimens from hyperplastic tissues obtained from 14 patients with BPH were evaluated for the density of alpha1-adrenoceptors in smooth muscle using autoradiography, Mallory-Azan staining and computer-assisted image analyses. The binding of [3H] tamsulosin (a selective alpha1-blocker) and the ratio of smooth muscle area was calculated, and the density of alpha1-adrenoceptors per area of smooth muscle determined by dividing the degree of binding by the ratio of smooth muscle to total area. RESULTS: There was a significant difference between the ratio of smooth muscle area in the hyperplastic acinar nodule and the surrounding stroma (P < 0.01). The density of alpha1-adrenoceptor per smooth muscle area was significantly higher in the hyperplastic acinar nodule than in the surrounding stroma (P < 0.05). There was no correlation between prostatic weight and the ratio of smooth muscle area or the density of alpha1-adrenoceptors in each region. CONCLUSION: The distribution of alpha1-adrenoceptors on smooth muscle differed with histological structure; both the histological conformation and the difference in the distribution of alpha1-adrenoceptors could affect urethral obstruction in BPH.

Autoradiography↗
PubMed1997

Immunohistochemical expression of glucose transporter-1 in human penile proliferative lesions.

Glucose transporters (GLUTs) are a family of membrane proteins responsible for the transport of glucose across cellular membranes. In terms of their mRNA levels, they have been reported to be expressed in some human tumours. However, the immunohistochemical localization of GLUTs in human urogenital lesions has rarely been studied. This study was performed to evaluate the expression of GLUT1 in penile proliferative lesions (18 cases of penile carcinoma and 13 cases of condyloma acuminatum). Using an isoform-specific anti-GLUT1 antibody, formalin-fixed paraffin-embedded sections were stained by the avidin-biotin complex method. In all cases of penile carcinoma, GLUT1 staining was diffusely recognized on the cell membrane of the carcinoma cells in the mainly infiltrating areas. However, the inner areas of the tumour were more weakly and focally stained. The intensity of staining for the penile carcinoma (staining score = 2.8 +/- 0.6) was stronger than that for condyloma acuminatum and that for adjacent non-proliferative areas. All cases of condyloma acuminatum showed a diffuse staining on the cell membrane in the basal and intermediate layers (staining score = 2.4 +/- 0.5). Non-proliferative (histologically normal) glans areas adjacent to the above lesions expressed the weakest GLUT1 staining only in the stratum basale (staining score = 1.8 +/- 0.5). These three areas showed significantly different staining scores from each other (p < 0.01). In conclusion, GLUT1 is expressed dominantly in penile proliferative lesions, especially in infiltrating areas of penile carcinoma.

Adult↗
PubMed1997

[A case of hormone-refractory prostate cancer responsive to low-dose prednisolone therapy].

A 67-year-old man with hormone-refractory (stage D2) prostate cancer was admitted to the hospital because of general malaise and bone pain. The patient had been receiving hormonal therapy, which was discontinued after admission. Instead, 10 mg per day of prednisolone was administered orally. His symptoms improved, and the serum prostate specific antigen (PSA) level decreased markedly. After 18 weeks of treatment with prednisolone, the serum PSA level rose again, and bone pain worsened. The patient died of cancer one month later.

Aged↗
PubMed1996

Detection of alpha 1-adrenoceptor subtypes in human hypertrophied prostate by in situ hybridization.

Adrenergic stimulation induces contraction of hypertrophied prostatic tissue via the alpha 1 adrenoceptor, and the results of pharmacological studies suggested the existence of adrenoceptor subtypes. Recently three subtypes (alpha 1a, alpha 1b, and alpha 1d) were cloned. Using probes for these subtypes, we demonstrated their expression in the tissues of ten cases of benign prostatic hypertrophy, using in situ hybridization. To determine the ratio between these subtypes, an RNase protection assay was also performed in three cases. Expression of the alpha 1a and alpha 1d adrenoceptors was diffuse in the smooth muscles of the interstitium, but was absent in glandular epithelial cells. On the contrary, the alpha 1b adrenoceptor was hardly detectable. The RNase protection assay confirmed the absence of the alpha 1b adrenoceptor, the ratio of alpha 1a and alpha 1d being 4:1. These results supported the idea that the differences in prostatic contractile response to several adrenergic drugs are based on the affinities of these drugs for the different subtypes.

Aged↗
PubMed1996

Decreased contractile effect of endothelin-1 on hyperplastic prostate.

1. The contractile activity, binding activity and localization of endothelin (ET)-1 were evaluated in human nonhyperplastic (control) and hyperplastic prostates. 2. ET-1 caused contraction of both prostates in a dose-dependent manner. However, this contraction was markedly decreased in hyperplastic prostates. 3. Bmax and Kd values of hyperplastic prostates were greater than those of the control. 4. The muscle and proliferative epithelium of hyperplastic prostates showed strong staining for the anti-ET-1 antibody. However, the glandular epithelium of control prostates was weakly stained. 5. These findings indicate that responsiveness to ET-1 is decreased, though the ET-1 and ET-1 receptors increase in the hyperplastic prostate. Namely, the increase in ET-1 receptors is not effective in regulating the contractile response of the prostate, because its expression is rather dominant in proliferated gland. 6. These suggest that ET-1 may not have an important role in the release of the obstructive symptoms of benign prostatic hypertrophy.

Aged↗
PubMed1996

Histochemical detection of intranuclear DNA fragmentation and its relation to the expression of bcl-2 oncoprotein in human prostatic cancer.

OBJECTIVE: To assess the incidence of intranuclear DNA fragmentation and the expression of the bcl-2 oncoprotein in prostatic carcinoma, both of which are related to programmed cell death. PATIENTS, MATERIALS AND METHODS: Specimens of tumour obtained from 17 patients with newly diagnosed prostatic carcinoma and 16 with hormone-treated prostatic carcinoma undergoing total prostatectomy were evaluated. DNA fragmentation was detected using the terminal-labelling method (d-uridine triphosphate conjugated with digoxigenin) and the expression of bcl-2 was detected immunohistochemically. RESULTS: There was a high incidence of intranuclear DNA fragmentation in 14 of 17 untreated tumours and 15 of 16 hormone-treated tumours. There were no differences between the positive cases in hormone-treated tumours and untreated tumours. There was significantly greater expression of bcl-2 in tumours treated with non-steroidal anti-androgen drugs (eight of nine were positive) than in those untreated (seven of 17) or treated with other drugs (one of seven) (P < 0.05). There was a consistent and marked dissociation between DNA fragmentation and bcl-2 positivity; most of the cells positive for bcl-2 showed no DNA fragmentation. CONCLUSION: The results indicated that cells positive for bcl-2 might potentially be hormone resistant and that the administration of non-steroidal anti-androgen drugs might have a role in the induction of hormone-resistant cells.

Aged↗
PubMed1996

[Urothelial carcinoma of the navicular fossa].

We report a case of transitional cell carcinoma arising in the fossa navicularis. The patient was a 74-year-old man. He had no history of sexually transmitted disease or urethral stricture. Clinically, the tumor was suspected to be a condyloma acuminatum; however, the pathological diagnosis yielded an unexpected result: transitional cell carcinoma. Radiological examinations and cystoscopy showed no other tumor besides the primary cancer in the fossa navicularis. Partial resection of the urethra was performed and the patient has been without evidence of disease for 3 years.

Aged↗
PubMed1995

Age-related changes in alpha 1-adrenoceptors in rat prostate.

The age-related changes in the density of alpha 1-adrenoceptors in the dorsolateral lobe of the rat prostate were evaluated in Wistar rats at 8, 52, and 104 weeks of age. [3H]YM617, a newly synthesized alpha 1-adrenergic blocker, was used as the ligand. The mean maximum number of binding sites, or alpha 1-adrenoceptor density (Bmax) +/- SE of 104-week-old rats (11.0 +/- 1.2 fmol/mg protein) was significantly lower than that in the 8-week-old rats (37.0 +/- 4.3 fmol/mg protein) and 52-week-old rats (37.2 +/- 3.4 fmol/mg protein) (respectively, P < 0.01). In contrast, mean affinity (Kd) values +/- SE of these groups showed no significant differences (8-week-old rats, 115.8 +/- 9.1; 52-week-old rats, 100.5 +/- 5.8; and 104-week-old rats, 116.4 +/- 9.8 pM). Mean volumes +/- SE of muscle cells of the prostate were 3.7 +/- 1.1 x 10(3) microns3 at 8 weeks, 30.0 +/- 6.2 x 10(3) microns3 at 52 weeks, and 18.6 +/- 8.2 x 10(3) microns3 at 104 weeks. Volumes for 8-week-old rats were significantly smaller than those for 52-week-old (P < 0.01) and 104-week-old rats (P < 0.05). However, the mean area density of the muscle cells showed no difference among the three groups: 20.1 +/- 2.2% at 8 weeks, 27.3 +/- 2.9% at 52 weeks and 20.3 +/- 3.4% at 104 weeks. In conclusion, the density of YM617-binding sites (alpha 1-adrenoceptors) in 104-week-old rats was lower than in 8- and 52-week-old rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic alpha-Antagonists↗
PubMed1995

Renal aging change of alpha 1-adrenoceptor in Wistar rats.

1. The aging changes of density of the alpha 1-adrenoceptors in the kidney were evaluated with Wistar rats of several ages (8, 52 and 104 weeks old). 2. [3H]prazosin and [3H]YM617 (newly synthesized alpha 1-blocker) were used for the ligand. The Bmax of [3H]prazosin was 74.0 +/- 9.5 fmol/mg/protein in 8 week, 52.1 +/- 7.3 fmol/mg protein in 52 week, and 31.3 +/- 4.2 fmol/mg protein in 104 week rats, and that of [3H]YM617 was 45.0 +/- 6.6 fmol/mg/protein in 8 week, 32.4 +/- 5.7 fmol/mg/protein in 52 week, and 19.3 +/- 5.5 fmol/mg/protein in 104 week rats. 3. The Bmax of both ligands for 104 week rats was significantly decreased compared to 8 week rats, however, 52 week rats showed no decrease of Bmax for both ligands. 4. The Kd values showed no difference in these three age groups for both ligands. 5. Autoradiographic study supported the result above mentioned. Furthermore, the binding sites of alpha 1-adrenoceptors were mainly in the cortex (vascular wall and peritubular area) and that alpha 1-adrenoceptors were chiefly chlorethylclonidine dihydrochloride (CEC) insensitive.

Adrenergic alpha-Antagonists↗
PubMed1995

Effect of bunazosin, alpha 1-adrenoceptor blocker, on multidirectional contractile response and localization of bunazosin binding sites in human hypertrophied prostate.

1. Effects of bunazosin, an alpha 1-adrenoceptor blocker, on the contraction induced by norepinephrine in human hypertrophied prostate were examined in vitro. 2. Prostatic specimens showed maximum contraction at 10(-4) M norepinephrine in longitudinal and circumferential directions to the urethra. 3. Bunazosin (10(-7) M) blocked norepinephrine-induced contraction with a parallel shift of the dose-response curve in both directions (pA2: 8.76 +/- 0.15; pA2: 8.90 +/- 0.08, respectively). 4. Serial sections of prostates were also evaluated by autoradiography. The binding sites were diffusely distributed in the interstitium. 5. We concluded that bunazosin affects multidirectional contraction in prostates.

Adrenergic alpha-1 Receptor Antagonists↗
PubMed1995

[Histochemical study of biotinylated lectins in prostatic cancer].

We examined the staining pattern of various lectins in the malignant and benign prostatic tissues to clarify the difference of sugar residues of mucosubstances between them. The binding of different lectins (Concanavalia ensiformis [Con A], Triticum vulgaris [WAG], Ricinus communis [RCA-I], Arachis hypogaea [PNA], Ulex europaeus [UEA-I], Glycine max [SBA], and Gliffonia simplicifolia II [GSA-II]) to cells of benign prostatic tissues (17 cases) and adenocarcinoma (54 cases) was evaluated immunohistochemically. SBA which was negative in benign epithelial cells, showed tendency to the binding to prostatic carcinoma (42.6%). UEA-I was significantly bound to the adenocarcinoma (68.5%) compared to the benign prostatic tissue (35.3%). We also examined histochemically 25 pairs of tissues obtained from prostatic adenocarcinoma before and after the various therapies with various lectins. The histological responsiveness on the post-therapeutic specimens showed a significant correlation to the clinical responsiveness to therapy. But the staining pattern of these 7 lectins on the pre-therapeutic specimens did not show a significant correlation to the clinical responsiveness to therapy. In summary, the staining pattern of some lectins in the prostatic cancers is different from that in the benign prostatic tissues.

Adenocarcinoma↗