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Biomedical subjects

K Nomata

Publications and source records attributed to K Nomata.

At least 19 recordsLinked to original sources
PubMed2001

Prognostic significance of platelet-derived endothelial cell growth factor/thymidine phosphorylase expression in stage pT1 G3 bladder cancer.

BACKGROUND: The management of patients with pT1 G3 bladder cancer remains controversial because of the high incidence of recurrence with muscle invasion. Thymidine phosphorylase (dThdPase) is identical to platelet-derived endothelial cell growth factor (PD-ECGF) and has angiogenic activity. The aim of this study was to determine whether the expression of PD-ECGF/dThdPase in bladder cancer tissue was associated with tumor progression and recurrence in patients with pT1 G3 bladder cancer. METHODS: Fifteen patients who were pathologically diagnosed as having pT1 G3 transitional cell carcinoma of the bladder were treated with transurethral resection. Sections of paraffin-embedded bladder tissue were immunohistochemically stained with either mAb654-1, a monoclonal antibody against human PD-ECGF or anti-CD34 monoclonal antibody, respectively. When more than 10% of tumor cells were positively stained with mAb654-1, this section was defined as positive in this study. RESULTS: Eight of 15 sections from patients with pT1 G3 bladder cancer (53%) were positive with PD-ECGF/dThdPase. During follow up, patients in the negative group had no disease progression and only two patients had local recurrence. In contrast, seven of eight positives had recurrence (P < 0.05) and progression was also observed in four recurrent patients. However, there was no statistical relationship between PD-ECGF and CD34 expression in any of the patients. CONCLUSION: The expression of PD-ECGF/dThdPase appears to be an important prognostic factor of pT1 G3 bladder cancer and did not show any significant relationship between PD-ECGF/dThdPase expression and vascular density.

Aged↗
PubMed2001

Angiogenin expression in superficial bladder cancer.

The concentration of angiogenin in the tumor tissues and corresponding normal tissues of 20 superficial bladder cancer patients was measured using a sandwich enzyme immunoassay (ELISA). In addition, immunohistochemical assays were performed in order to clarify the localization of angiogenin expression in bladder tissue. The mean concentration of angiogenin in the carcinoma tissues was significantly lower than that in the corresponding normal tissues (P < 0.001). Angiogenin expression was weak in the bladder cancer cells. The present results show that the expression of angiogenin is lower in superficial bladder cancer tissues than in corresponding normal tissues. The biological role of angiogenin in carcinogenesis of bladder cancer may be different from those of other angiogenic factors.

Adult↗
PubMed1999

Disruption of gap junctional intercellular communication in human renal cancer cell lines.

OBJECTIVES: Gap junctional intercellular communication (GJIC) is believed to play an important role in the maintenance of cell homeostasis, and its disruption may be associated with carcinogenesis. However, GJIC has not been detected in many human cancers. We therefore studied the regulation of GJIC in human renal cancer cell lines. METHODS: We examined the human renal cancer cell lines, ACHN and NT, as well as Madin-Darby canine kidney (MDCK) cells as a positive control, using GJIC assays, Northern blotting to detect connexin 43 mRNA, immunofluorescent staining, and Western blotting of connexin 43 protein. RESULTS: GJIC of ACHN and NT was completely blocked. In ACHN cells, connexin 43 mRNA was not altered. However, connexin 43 protein was aberrantly localized and phosphorylated connexin 43 protein had disappeared. Both connexin 43 protein and its mRNA were undetectable in NT cells. CONCLUSIONS: GJIC in human renal cancer cell lines is impaired and various pathways may inhibit this mechanism in renal cancer. We believe that connexin plays an important role in renal carcinogenesis.

Carcinoma, Renal Cell↗
PubMed1999

All-trans retinoic acid enhances gap junctional intercellular communication among renal epithelial cells in vitro treated with renal carcinogens.

Epidemiological and clinical studies imply that retinoids have a chemopreventative action against cancer and can suppress the growth of cancer cells. The regulation of connexin (Cx) expression by retinoids varies among tissues and organs. In this study, we investigated whether all-trans retinoic acid (ATRA) upregulates gap junctional intercellular communication (GJIC) in renal epithelial cells exposed to renal carcinogens. Madin Darby canine kidney (MDCK) cells were incubated with ATRA for 3 days, then briefly exposed to 12-O-tetradecanoyl-phorbol-13-acetate (TPA) or renal carcinogens potassium bromate (KBrO3) and dimethylnitrosamine (DMN). ATRA increased the expression of connexin 43 mRNA and protein without affecting Cx 43 phosphorylation and prevented inadequate Cx 43 localisation caused by TPA/KBrO3 or DMN. Consequently, ATRA prevented the disruption of GJIC in MDCK cells. These data suggest that ATRA enhanced GJIC by upregulating Cx 43 expression and that ATRA might be useful for prevention of renal cell carcinoma.

Blotting, Western↗
PubMed1999

Clinical experiences of microsurgical side-to-end epididymovasostomy for epididymal obstruction.

BACKGROUND: Some surgical treatments are performed for obstructive azoospermia in urology and good results have been reported. Of 61 azoospermic patients who visited our department of urology, nine were diagnosed as having epididymal obstruction of unknown etiology. METHODS: We describe nine consecutive side-to-end epididymovasostomy procedures performed on these patients. These procedures are microsurgical two-layer anastomosis. RESULTS: Of the nine men, five (55.6%) had sperm in the ejaculate postoperatively and, up until publication, the pregnancy rate was 33.3% (three of nine). CONCLUSIONS: These results suggest that reconstruction of the seminal tract should be considered first for obstructive azoospermia.

Constriction, Pathologic↗
PubMed1999

[A case of pyonephrosis caused by ureteral stones with elevated serum levels of CA19-9].

A case of pyonephrosis with high levels of serum CA19-9 antigen is reported. A 71-year-old woman was admitted with right flank pain. Computed tomography and ultrasonography showed severe hydronephrosis and hydroureter due to a right ureter stone. Laboratory data revealed a high level of serum CA19-9. However, no tumor was found in the pancreas, gallbladder, liver, gastrointenstinal tract or genitourinary tract. Drip infusion pyelography showed a non-functioning pattern of right kidney. Therefore, right nephroureterectomy was performed for right pyonephrosis. Histological examination revealed chronic inflammation. Malignant cells were not seen in the resected specimen. The serum CA19-9 levels before and after operation were 102.9 U/ml and 24 U/ml, respectively, being normal after the operation. Immunohistochemical examination revealed the presence of CA19-9 antigen in the urethelium, indicating its expression in the specimen. To our knowledge this might be the first case of pyonephrosis associated with high levels of serum CA19-9 antigen.

Aged↗
PubMed1998

The expression of platelet-derived endothelial cell growth factor in human bladder cancer.

Platelet-derived endothelial cell growth factor (PD-ECGF) is an angiogenic factor and in some studies PD-ECGF/dTdRPase expression levels in several kind of cancers were higher than in their surrounding normal tissues. In this study, we evaluated PD-ECGF/dTdRPase expression in bladder cancer by an immunohistological method and determined whether it correlated with tumor stage, grade and recurrence. PD-ECGF/dTdRPase expression was correlated with tumor grade and stage. Furthermore, among the superficial tumors, PD-ECGF/dTdRPase expression was correlated with a recurrence-free rate and thus it might be a prognostic factor for the recurrence of superficial bladder cancer.

Adult↗
PubMed1998

Cooperative effects of v-myc and c-Ha-ras oncogenes on gap junctional intercellular communication and tumorigenicity in rat liver epithelial cells.

The objective of this study was to isolate and partially characterize several rat liver epithelial cell clones containing myc, ras and myc/ras oncogenes in order to study their roles in apoptosis and to test the hypothesis that gap junctional intercellular communication is necessary for apoptosis in solid tissues and that the loss of junctional communication leads to tumorigenesis. The co-transfection of the myc and ras oncogenes in the normal rat liver epithelial cell line (WB-F344) resulted in a loss of functional channels and normal growth regulation; cell-cell communication was significantly decreased and tumorigenicity determined in adult male F344 rats was induced. We examined cell growth properties, gap junctional intercellular communication (GJIC), using the scrape-loading-dye transfer and fluorescence-redistribution-after-photobleaching assays, and tumorigenicity in a series of normal and v-myc-, c-Ha-ras- and v-myc/c-Ha-ras-transfected WB-F344 cell lines. The c-Ha-ras- and the v-myc/c-Ha-ras-transduced cell lines appeared distinctly different from the other lines, having spindle-shaped morphology, shorter generation time and contact insensitivity. On the other hand, the normal WB-F344 cell line and the v-myc-transduced cell line showed excellent GJIC. Moreover, the c-Ha-ras-transduced cell lines displayed decreasing levels of GJIC associated with their increasing tumorigenicity. The v-myc/c-Ha-ras-transformed cell lines showed the lowest levels of GJIC and were also the most tumorigenic. These findings suggest that the reduction of GJIC in c-Ha-ras- and v-myc/c-Ha-ras-transformed WB-F344 cells is linked to their tumorigenic potential. These cell lines should provide valuable tools to study the role of GJIC in apoptosis during tumorigenesis.

Animals↗
PubMed1998

HTLV-I-associated myelopathy associated with multi-organ inflammatory disease: a case report.

We report a 73-year-old man with human T-lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM) complicated with multi-organ inflammatory disease, including Sjögren's syndrome, interstitial cystitis, and uveitis. The presence of HTLV-I proviral DNA in peripheral blood mononuclear cells (PBMC), cerebrospinal fluid, salivary gland, mucosa of urinary bladder, and aqueous humor was confirmed by polymerase chain reaction using HTLV-I pX region primer. Western blot analysis revealed the presence of anti-HTLV-I antibodies in serum, CSF, saliva, and urine, suggesting replication of HTLV-I in each tissue. A high load of HTLV-I proviral DNA (20 copies out of 100 PBMC) was present, associated with increased spontaneous proliferation of peripheral blood lymphocytes (24,747 cpm). Our results suggest that the high load of HTLV-I in patients with HAM may potentially induce systemic inflammation in several organs.

Aged↗
PubMed1998

Changes in the gap junctional intercellular communication in renal tubular epithelial cells in vitro treated with renal carcinogens.

Gap junctional intercellular communications (GJIC) are known as the channels for the direct transfer of cytoplasmic molecules between neighboring cells and are lost during transformation of normal cells. To study the function and the molecular mechanism for the loss of GJIC, the effects of dimethylnitrosamine, KBrO3 and FeSO4 x 7H2O, which are known as chemical tumor promoters of the kidney on the GJIC function and the expression of connexin 43 of Madin-Darby canine kidney (MDCK) epithelial cells, were examined. These tumor promoters inhibited the GJIC in MDCK cells. The expression of connexin 43 mRNA and connexin 43 protein was not altered by these treatments, whereas immunocytochemical study revealed that the distribution of connexin 43 protein was changed from the cell surface to the cytoplasma. These data suggest that blockage of GJIC in MDCK cells treated with renal carcinogens support the hypothesis that loss of GJIC might be important in renal carcinogenesis.

Animals↗
PubMed1998

Preparation of monoclonal antibodies against N-(gamma-maleimidobutyryloxy)succinimide (GMBS)-conjugated acetylspermine, and development of an enzyme-linked immunosorbent assay (ELISA) for N1,N12-diacetylspermine.

We have developed three mouse monoclonal antibodies (mAb) of types IgG1 and IgG2b, i.e. anti-acetylspermine (Ac-Spm)-1 and 2 (ACSPM-1 and 2), and anti-acetylspermine (Ac-Spm)-3 (ACSPM-3), respectively, against Ac-Spm conjugated to bovine serum albumin via a heterobifunctional cross-linker, N-(gamma-maleimidobutyryloxy)succinimide (GMBS). Among these mAbs, ACSPM-2 was the most useful for the development of an enzyme-linked immunosorbent assay (ELISA) for acetylpolyamines (Ac-PAs) with glutaraldehyde (GA)-conjugated N1,N12-diacetylspermine (2Ac-Spm) or acetylspermine (Ac-Spm) as the solid phase antigen. However, GMBS-conjugated Ac-Spm did not behave as a solid phase antigen in the competitive ELISA. The ELISA is based on the principle of competition between an analyte and the conjugated antigen for the mAb, followed by immunoreaction with biotinylated anti-mouse immunoglobulin and horseradish peroxidase-streptavidin. The ACSPM-2 mAb reacted with 2Ac-Spm to the highest degree, followed by Ac-Spm, N1-acetylspermidine (N1-Ac-Spd), N8,N8-diacetylspermidine (2Ac-Spd), and spermine (Spm), the EC50 values being 0.06, 0.25, 7.0, 10, and 60 microM, respectively, but exhibited almost no cross-reaction with other polyamine-related compounds or amino acids. The method was used to determine the urinary Ac-PA levels in healthy subjects, the average value of 0.36 microg of 2Ac-Spm/g creatinine (n = 16) being obtained. The ACSPM-2 ELISA for 2Ac-Spm, which was the PA most relevant to the analysis of human urine among the five PA analogs mentioned above, might have potential for elucidation of the correlation of urinary 2Ac-Spm levels in cancers.

Animals↗
PubMed1998

Involvement of tyrosine phosphorylation of p185(c-erbB2/neu) in tumorigenicity induced by X-rays and the neu oncogene in human breast epithelial cells.

Ionizing radiation is the exogenous agent best proven to induce breast cancer. c-erbB2/neu amplification and overexpression are known to occur in breast cancer and are correlated with aggressive tumor growth and poor prognosis. We have developed simian virus 40-immortalized cell lines from normal human breast epithelial cells (HBECs) with luminal and stem-cell characteristics. In this study, we examined whether x-rays and a mutated neu oncogene are capable of inducing tumorigenicity in these cells. The results indicated that x-rays were effective in converting immortal non-tumorigenic HBECs to weakly tumorigenic cells that then could be transformed to highly tumorigenic cells by the neu oncogene. The in vitro growth of these tumorigenic cells was significantly faster than that of the parental non-tumorigenic cells in growth factor- and hormone-supplemented or -depleted media. The neu oncogene, however, had no tumorigenic effect on immortal non-tumorigenic cells. The expression of p185(c-erb82/neu) was elevated in neu-transduced immortal or weakly tumorigenic cell lines. However, only in the latter was p185(c-erbB2/neu) found to be phosphorylated at tyrosine residues. Thus, x-rays appear to induce a genetic alteration that confers weak tumorigenicity on immortal HBECs and interacts with p185(c-erbB2/neu) directly or indirectly to give rise to fast-growing tumors.

Animals↗
PubMed1997

Combined intraarterial chemotherapy and radiotherapy in the treatment of bladder carcinoma.

BACKGROUND: The combination of radiotherapy and cisplatin-based chemotherapy has proved to be an effective treatment for bladder carcinoma in many clinical studies. Intra-arterial approaches to chemotherapy have been developed to reduce systemic toxicities and improve response rates. This study was designed to determine the effectiveness of intra-arterial chemotherapy with cisplatin and doxorubicin combined with radiotherapy in the treatment of patients with invasive bladder carcinoma. The objectives were to evaluate the response rate, bladder preservation rate, toxicity, and survival rate. METHODS: Thirty-five patients with muscle-invasive bladder carcinoma at clinical stage T2-T4N0M0 were each treated with 2courses of intra-arterial cisplatin and doxorubicin at 3-week intervals, whereas radiotherapy was administered for 4 weeks (2 gray [Gy] given a total of 20 times, at 5 fractions per week). Patients with complete responses were given an additional course of chemotherapy (intra-arterial cisplatin and doxorubicin) and irradiation (20 Gy), and patients with residual tumor after the initial chemoradiotherapy underwent cystectomy. RESULTS: A clinical complete response was observed in 26 patients (74%; 95% confidence interval, 59-89%), and an incomplete response was observed in 9 (26%; 95% confidence interval, 11-41%). The bladder was preserved in all patients with a complete response, and it was tumor free in 19 of them (54% of all patients). The actuarial survival rate was 76.6% at 5 years. After a median follow-up interval of 45 months, 28 patients (80%) were alive and 7 (20%) had died due to disease progression. The regimen was well tolerated, with no severe systemic or local toxicities. CONCLUSIONS: The high rates of response, survival, and bladder preservation observed indicate that this combined intra-arterial chemotherapy and radiotherapy regimen would be useful in the management of invasive bladder carcinoma. This was a small Phase II trial; the results are preliminary, and the utility of this treatment modality in patient management remains to be proven.

Adult↗
PubMed1997

Stimulation of cell proliferation and inhibition of gap junctional intercellular communication by linoleic acid.

The effect of linoleic acid (LA) on gap-junction permeability, connexin 43 mRNA level, protein level, and phosphorylation, and the numbers of gap-junctional membrane plaques were studied in the rat liver epithelial cell line WB-F344 to determine whether changes in these parameters correlated with the enhanced cell growth and the inhibition of gap-junction function. When cultured in a medium with low serum (1%), these cells exhibited a slower growth rate than in the high serum medium (7%). Addition of linoleic acid (0.01-3 mg/ml) to the low serum medium increased the growth rate and inhibited gap junctional intercellular communication (GJIC) in a dose-dependent manner. In a comparison of short-term and long-term treatments with LA, GJIC in short-term treated (1 h) WB cells was inhibited at 3 mg/ml LA but readily recovered by washing and removing LA from cells, whereas GJIC in long-term treated (6 days) WB cells did not recover by washing and removing LA from WB cells. Western blot analysis of connexin 43 showed that a short-term incubation with linoleic acid increased the relative amount of unphosphorylated connexin 43 protein, but a long-term incubation with linoleic acid decreased the amount of unphosphorylated connexin 43 protein and increased the relative amount of hyperphosphorylated connexin 43 protein. Connexin 43 and p53 mRNA levels decreased in a time- and dose-dependent manner in linoleic acid-treated cells. These results suggest that growth stimulation and gap junctional intercellular communication inhibition of rat liver epithelial cells by linoleic acid may be mediated in part through modulation of p53 expression and function.

Animals↗
PubMed1997

Transarterial infusion of cisplatin and doxorubicin in bladder cancer.

Forty-five patients (median age 63 years) with muscle invasive bladder cancer were treated with transcatheter intraarterial infusion (TAI) of cisplatin (CDDP) and doxorubicin. They received a total of 114 courses (median 3 courses per patient) of TAI. Complete response was obtained in 20 patients (44%), partial response in 17 (38%), stable disease in 6(13%), and progression of disease in 2 patients (5%). The overall response rate was 82% at a median follow-up of 36 months. The actuarial survival of the patient population was 72% at 5 years; 36 patients were alive and 9 had died of cancer progression. The treatment was generally extremely well tolerated without major complications. The current study also revealed the fact that papillary carcinomas were more sensitive to this therapy than were non-papillary tumors. Overall, response rate and local control were significantly higher in low-grade than in high-grade tumors. The observed high complete response and good survival rate suggest that intraarterial CDDP and doxorubicin might be highly effective for localized invasive bladder cancer.

Adult↗
PubMed1996

Inhibition of gap junctional intercellular communication in heptachlor- and heptachlor epoxide-treated normal human breast epithelial cells.

Based on the concern of organochlorides in the environment and in human tissue, this study was designed to determine whether various noncytotoxic levels of heptachlor and heptachlor epoxide could inhibit, reversibly, gap junctional intercellular communication in human breast epithelial cells (HBEC). Cytotoxicity and gap junctional intercellular communication (GJIC) were evaluated by lactate dehydrogenase assay and fluorescence redistribution after photobleaching analysis, respectively. Both heptachlor and heptachlor epoxide were noncytotoxic up to 10 microg/ml. At this concentration, heptachlor and heptachlor epoxide inhibited GJIC of normal human breast epithelial cells after 1 h treatment. Within a 24 h treatment with heptachlor and heptachlor epoxide at 10 microg/ml, recovery of GJIC had not returned. GJIC completely recovered after a 12 h treatment of 1 microg/ml heptachlor epoxide, but it did not recover after a 24 h treatment of 1 microg/ml heptachlor. RT-PCR and Western blots were analyzed to determine whether the heptachlor or heptachlor epoxide might have altered the steady-state levels of gap junction mRNA and/or connexin protein levels or phosphorylation state. No significant difference in the level of connexin 43 (Cx43) message between control and heptachlor-treated cells was observed. Western blot analyses showed hypophosphorylation patterns in cells treated with 10 microg/ml heptachlor and heptachlor epoxide for 1 h with no recovery within 24 h. Immunostaining of Cx43 protein in normal HBEC indicated that heptachlor and heptachlor epoxide caused a loss of Cx43 from the cell membranes at noncytotoxic dose levels. Taken together, these results suggest that heptachlor and heptachlor epoxide can alter GJIC at the post-translational level, and that, under the conditions of exceeding a threshold concentration in the breast tissue containing 'initiated' cells for a long time and not being counteracted by anti-tumor-promoting chemicals, they could act as breast tumor promoters.

Base Sequence↗