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81.
82.
An expression of ras p21 proteins on cholangiocarcinoma (CC) (intrahepatic bile duct carcinoma) cells was examined by an immunoperoxidase method using an appropriate dilution of mouse monoclonal antibody RAP-5, with which no positive staining was obtained in livers with normal histology. Of 44 CCs examined 39 were positive for the antigens; well-differentiated adenocarcinoma usually showed a diffuse weak, cytoplasmic staining in nearly all tumor cells with the same staining intensity, while in moderately and poorly differentiated adenocarcinoma the expression of p21 varied markedly in intensity from cell to cell in the same cell nest. The number of positive cells decreased with the grade of tumor, and no or little staining was observed in undifferentiated areas. These findings indicate that the expression of ras p21 antigens was lost with increasing dedifferentiation of tumor cells. Carcinoembryonic antigens (CEA) were positive in 42 of 44 CCS. Well-differentiated adenocarcinoma expressed CEA along the apical surfaces of the tumor glands. With the dedifferentiation of tumor cells, the expression of CEA became prominent not only at the apical surfaces but also on the basolateral surfaces and in the cytoplasms, and further in the surrounding stromal tissue. There was no clear-cut correlation between the expression of p21 antigens and the production of CEA in CCs. 相似文献
83.
84.
Y Mizukami A Nonomura M Noguchi T Taniya N Koyasaki Y Saito T Hashimoto F Matsubara N Yanaihara 《Anticancer research》1991,11(4):1485-1494
The expression of the oncogene products ras p21, c-myc and the growth factor EGF (epidermal growth factor) was studied immunohistochemically in the tissue of 119 benign and malignant human breasts. In most cases, histologically normal breast tissues and benign lesions were found to be negative or poorly-expressive for reactivity with each antibody. Similar findings were observed in carcinoma in situ. Invading breast carcinomas demonstrated a significantly higher percentage of stained cells than that observed in benign lesions or carcinoma in situ; forty-two of 66 invasive breast carcinomas (63.6%) were highly-expressive for ras p21, thirty-eight (57.6%) for c-myc and twenty (30.3%) for EGF, but overall correlations between each oncogene expression and the clinical stage, tumor size or degree of differentiation were not found. The overall 5-year survival rate was studied in 58 patients with Stage II and III in association with each oncogene or EGF expression. Their survival rate was significantly effected by the EGF expression (0.05 less than p less than 0.1) but not by ras p21 or c-myc expression. Analysis of 36 specimens available with ER (estrogen-receptor) level revealed a significant correlation between the ER status and c-myc or E2 (estradiol) and a significant inverse correlation between ER status and ras p21 or EGF expression (P less than 0.05). The expression of ras p21, EGF and c-myc was not associated with metastatic tumor progression. 相似文献
85.
Y Okabe S Nakamura H Okumura S Matano K Kobayashi S Ohtake T Yoshida T Matsuda Y Mizukami A Nonomura 《Anticancer research》1991,11(6):2031-2035
In order to examine the relationship between argyrophilic proteins of nucleolar organizer regions (AgNORs) and the proliferation activity of cells, we investigated lymph nodes obtained from 25 untreated non-Hodgkin's lymphoma (NHL) patients. Two monoclonal antibodies (MoAb) (Ki-67 antibody and anti-DNA polymerase alpha antibody) were used for evaluating cell proliferation activity. A linear relation between the mean number of agNORs per nucleus and the proportion of NHL cells reacting with Ki-67 MoAb was observed (r = 0.48, P less than 0.05). A similar relation between AgNORs and DNA polymerase alpha MoAb was also observed (r = 0.51, P less than 0.01). From these data, it was confirmed that AgNORs reflect the proliferation activity of NHL cells. We conclude that the AgNOR staining procedure is one of the simplest and most reliable methods for analyzing cell proliferation potential. 相似文献
86.
Calcium-independent phosphorylation of smooth muscle myosin light chain by okadaic acid isolated from black sponge (Halichondria okadai) 总被引:7,自引:0,他引:7
H Ozaki H Ishihara K Kohama Y Nonomura S Shibata H Karaki 《The Journal of pharmacology and experimental therapeutics》1987,243(3):1167-1173
Previously, we have shown that okadaic acid (OA), isolated from black sponge (Halichondria okadai) causes contraction even in the absence of Ca++ in the saponin-permealized taenia isolated from guinea pig cecum. In the present study, mechanism of action of OA was examined using native actomyosin extracted from chicken gizzard smooth muscle. In the absence of Ca++, OA (0.1-1 microM) induced superprecipitation and increased the Mg++-adenosine triphosphatase activity. The OA-induced superprecipitation was enhanced by Ca++ at a concentration (greater than 0.1 microM) which did not activate the calmodulin-dependent myosin light chain (MLC) kinase. The effect of OA was not affected by the calmodulin inhibitor, trifluoperazine, at a concentration (100 microM) needed to inhibit the Ca++-induced response, but was inhibited markedly by the nonselective kinase inhibitors, amiloride (1 mM) and K-252a (5 microM). The OA-induced superprecipitation in the absence of Ca++ was accompanied by phosphorylation of the 20 K dalton MLC, which also was enhanced by low concentration of Ca++ (greater than 0.1 microM). OA did not change the phosphatase activity which dephosphorylates the phosphorylated MLC. An activator of Ca++- and phospholipid-dependent protein kinase, 12-O-tetradecanoylphorbol 13-acetate (1 microM), did not modulate superprecipitation or phosphorylation of MLC in the presence and absence of OA. Furthermore, inhibitors of Ca++ and phospholipid-dependent protein kinase, 1-(5-isoquinoline-sulfonyl)-2-methylpiperazine dihydrochloride (400 microM) and polymyxin B (100 micrograms/ml), affected neither superprecipitation nor phosphorylation of MLC induced by OA. With a reconstituted system containing purified myosin and MLC kinase, OA induced only slight phosphorylation of MLC.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
87.
H Fukatsu H Yamada H Nonomura Y Miyagawa Y Hatano M Waki S Hiraiwa T Muramatsu Y Yamada E Nishikawa 《Hinyokika kiyo. Acta urologica Japonica》1987,33(12):1943-1950
The tumor line in nude mice is one of the most important experimental animal models for oncodevelopmental studies. We implanted a human ureteral tumor into nude mice, established the tumor line, AM-UT-1, and maintained it by serial transplantation. The characteristics of this tumor line in nude mice are reported. Histologically, the original tumor was a transitional cell carcinoma (grade II, stage B). The transplanted tumor grew locally and had a constant growth pattern during serial passage until the 13th passage in nude recipients and maintained the basic histological, immunohistochemical findings of the original tumor. Both original tumor and serial transplanted tumor had carcinoembryonic antigen (CEA)-producing activity. A high level of serum CEA was also recognized in nude mice. 相似文献
88.
89.
Norio Igarashi Takashi Nozawa Nozomu Fujii Bun-ichi Kato Makoto Nonomura Akira Matsuki Teruo Nakadate Akihiko Igawa Hidetsugu Asanoi Minoru Inoue Hiroshi Inoue 《Journal of nuclear medicine》2005,46(1):160-164
We investigated whether changes in myocardial uptake of fatty acid tracer after reperfusion following transient myocardial ischemia were closely related to alterations in intracellular fatty acid oxidation. METHODS: Using a fatty acid tracer of (131)I- and (125)I-labeled 15-(p-iodophenyl)-9-methylpentadecanoic acid (9MPA), the myocardial uptake and metabolites were determined by dual-tracer autoradiography and thin-layer chromatography in rats 3 or 14 d after reperfusion following 5 or 15 min of ischemia induced by coronary artery ligation. RESULTS: 9MPA metabolites processed via beta-oxidation were lower in the ischemic region (IR) than in non-IR 3 d after 5 min of ischemia, despite no reduction of tracer uptake in IR. Oxidation of 9MPA was recovered 14 d after 15 min of ischemia in association with normalization of tracer uptake in IR, whereas both uptake and oxidation of 9MPA were markedly impaired 3 d after 15 min of ischemia, accompanied by slow clearance of myocardial tracer. CONCLUSION: Normal uptake of fatty acid tracer early after reperfusion does not always imply preserved intracellular fatty acid oxidation. However, reduction of tracer uptake might reflect impaired fatty acid oxidation. 相似文献
90.
The development of more specific biomarkers for prostate cancer and/or high‐risk prostate cancer is necessary, because the prostate‐specific antigen test lacks specificity for the detection of prostate cancer and can lead to unnecessary prostate biopsies. Urine is a promising source for the development of new biomarkers of prostate cancer. Biomarkers derived from prostate cancer cells are released into prostatic fluids and then into urine. Urine after manipulation of the prostate is enriched with prostate cancer biomarkers, which include prostate cancer cells, DNAs, RNAs, proteins and other small molecules. The urinary prostate cancer antigen 3 test is the first Food and Drug Administration‐approved RNA‐based urinary marker, and it helps in the detection of prostate cancer on repeat biopsy. The SelectMDx test is based on messenger RNA detection of DLX1 and HOXC6 in urine after prostate massage, and helps in the detection of high‐risk prostate cancer on prostate biopsy. Exosomes are extracellular vesicles with a diameter of 30–200 nm that are secreted from various types of cells. Urinary prostate cancer‐derived exosomes also contain RNAs and proteins specific for prostate cancer (e.g. PCA3 and TMPRSS2‐ERG), and could be promising sources of novel biomarker discovery. The ExoDx Prostate test is a commercially available test based on the detection of three genes (PCA3, ERG and SPDEF) in urinary exosomes. Advancement of comprehensive analysis (microarray, mass spectrometry and next‐generation sequencing) has resulted in the discovery of several urinary biomarkers. Non‐invasive urinary markers can help in the decision to carry out prostate biopsy or in the design of a therapeutic strategy. 相似文献