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1.
《Cell》2021,184(26):6281-6298.e23
2.
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
3.
Z. Ouanes I. Ayed-Boussema T. Baati E.E. Creppy H. Bacha 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2005,565(2):139-149
The cytogenetic effect of zearalenone (ZEN), a non-steroidal estrogenic mycotoxin, was evaluated in vivo, in mouse bone marrow cells, by assessing the percentage of cells bearing different chromosome aberrations. The studies included different conditions for animal treatment, as follows: (1) single intraperitoneal (ip) injection, (2) repeated ip injections, (3) pre-treatment for 24 h with Vitamin E (Vit E), and (4) pre-treatment for 4 h with 17β-estradiol (17β-Est) or progesterone (Prog). ZEN induced different types of chromosome aberrations, which was concentration-dependent (2–20 mg/kg bw). These doses corresponded to 0.4–4% of the LD50 in the mouse. Interestingly, when the dose of ZEN (40 mg/kg) was fractionated into four equivalent doses (4 × 10 mg/kg bw), into three doses (15 + 10 + 15 mg/kg bw), or into two equivalent doses (2 × 20 mg/kg bw), given every 24 h, the percentage of chromosome aberrations increased significantly. This finding suggests that ZEN proceeds by reversible binding on receptors that could become saturated, and that it damages the chromosomes in a ‘hit and go’ manner. Furthermore, pre-treatment of animals with 17β-estradiol or progesterone significantly decreased the percentage of chromosome aberrations, suggesting that (i) these hormones bind to the same cytoplasmic receptors transported into the nucleus to elicit DNA damage, (ii) they may play a role in preventing chromosome aberrations induced by ZEN. Similarly, Vit E prevented these chromosome aberrations indicating that Vit E, previously reported to prevent most of the toxic effects induced by ZEN, may also bind to the same receptors. 相似文献
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Gene cha-1.unc-17 of the nematode Caenorhabditis elegans is a complex gene, consisting of at least two complementation groups. One part (cha-1 region) of the gene encodes the enzyme choline acetyltransferase (ChAT), but the function of the other part (unc-17 region) is still unclear. We measured the ChAT activity and ACh levels of the cha-1 and unc-17 complex gene mutants. We show here that alterations in ACh levels, rather than the ChAT activity, reflect abnormal phenotypes accompanying cha-1.unc-17 mutations, that is, the decreased ACh levels in cha-1 mutations and abnormal accumulation in unc-17 mutations. Our results suggest that the unc-17 region may encode functions necessary for storage and/or release of ACh at the presynaptic level. 相似文献
7.
Shyamali Mukherjee Mihir Nag Tultul Nayyar Indrani Maitra Parul Chakrabarti Pramod R. Dasgupta 《Journal of biosciences》1986,10(3):311-317
The effect of estradiol-17β and progesterone given separately as well as in combination on the rate of hydrogen peroxide formation
and lipid peroxidation in the uteri of ovariectomized rats was studied. Estradiol in 3μg dose per day per animal elicited maximum stimulatory response and progesterone (100μg), on the other hand, was without any such effect. However, progesterone given along with estradiol completely prevented the
effect due to the latter. In the same way, vitamin E, a well known antioxidant was found to be extremelv effective in protecting
the uterus from the highly peroxidative action of estradiol-17β. 相似文献
8.
Adult sockeye salmon, Oncorhynchus nerka (Walbaum), treated with salmon pituitary extract in July survived for up to 47 days and developed nuptial colours in both male and female fish during this period, whereas no such characteristics appeared in untreated control fish. Furthermore, results showed that 20 of 50 adult female Philomena oncorhynchi recovered from the 15 treated fish contained fully developed tailed larvae in the uterus as compared with only one of 44 female P. oncorhynchi from 31 untreated control fish. None of 51 worms from 13 stilboestrol treated adult sockeye showed development in utero beyond an elongated embryo, nor did the host fish develop nuptial colours. P. oncorhynchi and its immature sockeye host (approx. 1 year prior to spawning) remained unaffected by any of three separate hormone treatment experiments using injection of salmon pituitary extract, injection of 17-β-estradiol, and stilboestrol mixed in the food. 相似文献
9.
Levonorgestrel which binds with high affinity to SHBG, is suggested as a new radioligand for estimation of SHBG in human plasma. Using 3H-levonorgestrel as a ligand, a number of samples from men, women pregnant and non-pregnant were analysed. The SHBG content was lowest in men, low in women and rose to higher level during pregnancy. The results of the present study suggest that levonorgestrel appears to be a better ligand than dihydrotestosterone for measuring SHBG. 相似文献
10.
Prevention of ultraviolet radiation- or chemical carcinogen-induced morphologic transformation and inhibition of tumor-producing transformed cell growth by lymphotoxin and by normal spleen leukocytes were quantitatively compared to define the antineoplastic activity spectra of these natural immune mediators. When Syrian golden hamster embryo cells seeded for colony formation in culture dishes were treated simultaneously with carcinogen and lymphotoxin, the number of morphologically transformed cell colonies was irreversibly reduced by 50% in the presence of 6 units of lymphotoxin/ml. Lymphotoxin inhibition of tumor cell growth, however, was reversible and 50% reduction in tumor cell growth in three transformed lines required 124, 330, and 477 units/ml. Thus, the anticarcinogenic activity of lymphotoxin can be 20-fold or more greater than its tumor growth-inhibitory activity. Similarly spleen leukocytes also were more effective as an anticarcinogen than as an inhibitor of tumor cell growth, consistent with previous observations that naturally occurring spleen leukocyte antineoplastic activity may result from lymphotoxin secretion. 相似文献