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Masayo Suzuki Hiroyuki Ishida Yukimasa Shiotsu Taisuke Nakata Shiro Akinaga Shigemitsu Takashima Toshiaki Utsumi Toshiaki Saeki Nobuhiro Harada 《The Journal of steroid biochemistry and molecular biology》2009,113(3-5):195-201
In order to evaluate the importance of estrogen production in tumor and surrounding tissues, we measured mRNA expression levels of 5 enzymes participating to estrogen synthesis in situ and 4 breast cancer-related proteins in 27 pairs of tumor and non-malignant tissues. Steroid sulfatase (STS) mRNA was more frequently detected in tumor tissues rather than in their non-malignant counterparts. Estrogen sulfotransferase (EST) was constantly expressed with high level not only in tumor tissues but also in their surrounding non-malignant counterparts. In contrast, mRNA expression levels of aromatase, and 17β-hydroxysteroid dehydrogenase type I and II were relatively low and detected only in small proportion of the patients. We also measured the mRNA expression levels of the same nine genes in tumor tissues of 197 breast cancer patients, and analyzed relationship between the mRNA expression level and the clinicopathological parameters. The mRNA expression levels of STS, aromatase and erbB2 in tumor tissues increased as breast cancer progressed. The tumoral mRNA expression levels of STS, estrogen receptor β, and erbB2 in patients with recurrence were higher than those in patients without recurrence. Upregulation of STS expression plays an important role in tumor progression of human breast cancer and is considered to be responsible for estrogen production in tumor and surrounding tissues. 相似文献
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Ishida Takuya Uehara Yoshitoshi Ikeya Tohru Haraguchi Takashi F. Asano Satoshi Ogino Yohei Okuda Noboru 《Limnology》2020,21(3):403-413
Limnology - Controlling phosphorous (P) loads from rice fields is important for the conservation of aquatic ecosystems, in part because P is relatively concentrated at its sources. Recently, winter... 相似文献
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Masatoshi Kataoka Keizoh Kawamura Tamotsu Kondoh Yoichi Wakano Hiroshi Ishida 《FEMS microbiology letters》1993,107(1):111-114
Abstract A factor showing inhibitory activity against human gingival fibrolasts was extracted from the cytosol fraction of Actinobacillus actinomycetemcomitans Y4. The activity markedly inhibited the proliferation of human gingival fibrolasts, but had no effect on cell viability or gross morphology. No such activity was found in cytosol fractions from either Porphyromonas gingivalis 381 or Escherichia coli HB101. The extract from A. actinomycetemcomitans Y4 was then purified by anion-exchange chromatography, hydroxyapatite chromatography and gel-filtration chromatography to give a single band on SDS-PAGE with an apparent molecular mass of 65 kDa. The purification ratio was 183-fold with a recovery rate of 5% compared with the crude extract (starting material) when the activity was assessed by direct cell counts. 相似文献
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The catalase molecule in germinating pumpkin cotyledons is synthesizedas a precursor (59-kDa) form, whose relative molecular massis larger than the mature enzyme (55-kDa). Although both typesof molecules are localized in the microbodies, the 59-kDa specieshas been shown to be present predominantly in the leaf peroxisomesisolated from green cotyledons, while the 55-kDa species ispredominantly in the glyoxysomes from etiolated cotyledons [Yamaguchiet al. (1984) Proc. Natl. Acad. Sci. USA, 81: 4809]. We examinedthe distribution of the 59- and 55-kDa catalase molecules indark- and light-grown tissues of pumpkin seedlings as well asin other plant species, using the immunoblotting technique.The ratios of the 59- and 55-kDa catalase species differed inthe pumpkin tissues examined. Light interferes with the conversionof the 59-kDa precursor to the 55-kDa form, especially in thecotyledons. The effect of light was less pronounced in the rootsand hypocotyls, indicating that the light regulation of theconversion is tissue-specific. Dark- and light-grown cotyledonsfrom cucumber and watermelon seedlings showed a similar lightregulation, suggesting that cucurbitaceous plants possess similarlight-regulatory mechanism. From the analysis of catalase proteinfrom various plant tissues, a limited correlation between molecularforms of catalase and different microbody populations was observed. (Received September 6, 1986; Accepted December 4, 1986) 相似文献