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971.
Yolanda S. López-Boado Irene Díez-Itza Jorge Tolivia Carlos López-Otín 《Breast cancer research and treatment》1994,29(3):247-258
Summary We have studied the hormonal regulation of the gene encoding Zn-2-glycoprotein (Zn-2-gp), a human protein with a high degree of amino acid sequence similarity to class I histocompatibility antigens that is produced by a specific subset of breast carcinomas. Northern blot analysis revealed that dexamethasone and 5-dihydrotestosterone strongly induced the accumulation of Zn-2-gp mRNA in T-47D human breast cancer cells. Furthermore, the effect of these two hormones was shown to be additive, since the combination of both hormones produced a stimulation of Zn-2-gp mRNA of at least 3-fold over that produced by either hormone alone. By contrast, the addition of 5-dihydrotestosterone, 17-estradiol, or progesterone failed to induce the expression of Zn-2-gp. The stimulatory effect of glucocorticoids and androgens on Zn-2-gp expression was produced in a time and dose dependent manner, without significantly affecting the cell proliferation rate. A time-course study demonstrated that the induction of Zn-2-gp mRNA by androgens and glucocorticoids reached a level of 4 or 3.2-fold over the untreated control after seven days of incubation in the presence of a 10–7 M concentration of 5-dihydrotestosterone or dexamethasone, respectively. A dose-response study showed that as little as 10–11 M of 5-dihydrotestosterone or dexamethasone produced an accumulation of Zn-2-gp mRNA of 2.4 or 2.1-fold over the control, respectively. On the basis of these results, we propose that Zn-2-gp may be useful as a biochemical marker of breast carcinomas with a specific pattern of hormone responsiveness in whose development glucocorticoids and/or androgens may play a significant role. 相似文献
972.
973.
以(86)Rb示踪法,观察3种肿瘤细胞的钠系转运活性及冬凌草甲素(Orid.)对其的影响。结果表明:(Orid.)腹腔注射及体外作用均能显著抑制艾氏腹水瘤细胞的钠系转运功能;体外作用12小时,半数抑制浓度约为5μg/ml,在此浓度下,药物作用1小时的抑制率为22%。同时测定人癌细胞系7901,Hep-2的钠泵活性高于人胚肺纤维母细胞系SL,且对Orid.较敏感。本文结果提示Orid.抗癌机理可能与钠泵活性抑制有关,从生物膜转运角度进一步证明Orid.的抗肿瘤作用。 相似文献
974.
A 52-year-old Japanese woman developed dermatomyositis. She had undergone a standard radical mastectomy for left breast cancer
21 years earlier. Though no physical sign of recurrent breast cancer appeared clinically, levels of tumor markers were abnormally
elevated. Therefore, tamoxifen and CAF therapy were given. Further, the clinical course of dermatomyositis almost paralleled
the level of serum tumor markers and the clinical course of her recurrent breast cancer. These markers were useful for detecting
the recurrence, following the metastatic disease, and monitoring her response to therapy. 相似文献
975.
Tumor necrosis factor-{alpha} up-regulates Bcl-2 expression and decreases calcium-dependent apoptosis in human B cell lines 总被引:7,自引:0,他引:7
Genestier Laurent; Bonnefoy-Berard Nathalie; Rouault Jean-Pierre; Flacher Monique; Revillard Jean-Pierre 《International immunology》1995,7(4):533-540
Group I and Epstein–Barr virus-negative Burkitt's lymphomacell lines and the B104 lymphoma cell line which expresses aphenotype of immature B cells undergo apoptosis after cross-linkingof their surface Ig receptors or after exposure to a calciumionophore. We show here that tumor necrosis factor (TNF)- protectsthese B cell lines against Ca2+-dependent apoptosis. Protectionwas associated with up-regulatlon of bcl-2 mRNA and proteinexpression. The increase of Bcl-2 expression induced by TNF-was inhibited by chelerythrine, a specific inhibitor of proteinkinase C (PKC), suggesting that Bcl-2 expression was dependenton PKC activation. Furthermore, we show that phorbol estersand cyclosporin A (CsA), which prevent Ca2+-dependent apoptosis,up-regulated Bcl-2 expression. The effect of CsA on Bcl-2 expressionis controlled by calcineurin since we have shown that FK506but not rapamycin had the same effect on Bcl-2 expression, whereasokadaic acid, an inhibitor of phosphatases 1, 2A and 2C, wasineffective. These data provide direct evidence that TNF- preventsCa2+-dependent apoptosis by a Bcl-2-dependent mechanism mediatedby PKC. 相似文献
976.
Motonobu Kameyama Kiichi Ishiwata Yuji Tsurumi Jun Itoh Kiyotaka Sato Ryuichi Katakura Takashi Yoshimoto Jun Hatazawa Masatoshi Ito Tatsuo Ido 《Journal of neuro-oncology》1995,23(1):53-61
Summary Positron emission tomography was used to investigate the metabolism of nucleic acids by18F-fluoro-2-deoxyuridine (18F-FUdR) in 22 patients with gliomas. Sixteen cases of high grade glioma clearly demonstrated a region of high activity with a differential absorption rate (DAR) of 0.64 ± 0.34. Six cases of low grade glioma failed to reveal a positive image of the tumor and the DAR in tumor was 0.21 ± 0.042 (p < 0.01). This PET-18F-FUdR study succeeded in differentiating high and low grade gliomas from the view point of nucleic acid metabolism. 相似文献
977.
Julia Malamitsi John Zorzos Alexandra D. Varvarigou Spyridon Archimandritis Catherine Dassiou Demosthenes V. Skarlos Panayotis Dimitriou Michael Likourinas Adamantia Zizi Charalambos Proukakis 《European journal of nuclear medicine and molecular imaging》1995,22(1):25-31
The aim of this study was the immunolocalization of transitional cell carcinoma of the bladder with a radiolabelled murine tumour-associated monoclonal antibody and the measurement of the absolute uptake of the antibody by the tumour. Fourteen patients with transitional cell carcinoma of the bladder received 3–6 mCi (111–222 MBq) of technetium-99m labelled HMFG1 monoclonal antibody intravesically and one patient, 2 mCi (74 MBq) of iodine-131 labelled 11.4.1, which is a non-tumour-specific monoclonal antibody. Four of the 15 patients were evaluated with singlephoton emission tomography (SPET) 1 1/2 to 2 h post administration. All patients underwent transurethral resection of the bladder tumour within 12–20 h following intravesical administration of the radiolabelled antibody. The radioactivity of biopsy specimens from normal urothelium and tumour areas were counted in a gamma counter. The mean uptake of the radiolabelled antibodies from normal and tumour sites was expressed as a percentage of the administered dose per kilogram of tissue. Conventional histology and immunohistochemistry using HMFGI monoclonal antibody were performed on paraffin sections of the biopsy specimens. Although our results are preliminary, it can be concluded that: (a) bladder tumours are well imaged by SPET when using99mTc-HMFG1; (b) intravesically administered radiolabelled antibody remains on the bladder tissue and does not escape into the systemic circulation; (c) the wide range of tumour uptake values (0%–9.3% administered dose/kg) observed probably can be attributed to heterogeneity of the antigenic expression of the tumour; (d) values of99mTc-HMFGI monoclonal antibody uptake by the tumour do not justify future attempts at radioimmunotherapy. 相似文献
978.
本文对合肥市1993—1997年城区居民恶性肿癌死亡进行了分析,结果显示恶性肿瘤死亡率居该市死因第一位,死亡居前的是肺癌、胃癌、肝癌、食管癌,50—69岁年龄段人群恶性肿瘤死亡率成倍增长,70—80岁年龄段癌症死亡率最高,分析表明老年人是暴露恶性肿癌危险因素高危人群,是癌症防治的重点人群。 相似文献
979.
980.
P^16基因蛋白在子宫颈鳞癌组织中的表达 总被引:3,自引:1,他引:2
应用免疫组织化学方法对58例子宫颈鳞状上皮细胞癌及5例宫颈上皮内瘤样病变标本的P^16基因表达进行研究,取8例正常子宫颈组织作对照,结果显示:P16基因的阳性表达率在宫颈鳞癌,宫颈上此内瘤样病谱及正常宫颈组织中分别为43.1%,40%,12.5%,肿瘤病理分级越低,临床分期越晚,阳性表达率越低,差异有显著性(P<0.05),提示:P16基因的异常表达在子宫颈鳞癌的发生,发展过程中起重要作用。 相似文献