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1.
Background/Aims: This study aimed to evaluate the parameters associated with the presence of androgen receptors in hepatocellular carcinoma and surrounding non-tumoral liver. Furthermore, we have assessed whether androgen receptor positively influences disease recurrence after surgical resection.Methods: Androgen receptor concentration was calculated by receptor binding assay in tumoral and non-tumoral liver in 43 patients (40 of them with cirrhosis) with hepatocellular carcinoma who underwent surgical resection.Results: Androgen receptors were found in 28 of the tumoral and in 30 of the non-tumoral samples, at concentrations ranging between 5 and 211 fmol/mg protein. The presence of androgen receptors within the tumor was significantly related to a smaller tumor size. Thereby, 22 of the 29 nodules ≤3 cm contained androgen receptors, while this occurred in only six of the 14 tumors larger than 3 cm (p<0.05). In contrast, the only parameter associated with the presence of androgen receptors in the non-tumoral liver was a lower gamma-glutamyltranspeptidase concentration. Disease recurrence after surgical resection was not only related to some tumor characteristics (increased alfa-fetoprotein concentration, presence of satellites, differentiation degree), but also to the presence of androgen receptors in the surrounding liver. Thus, the probability of recurrence after 1- and 2-year follow up in patients with androgen-positive livers was 33% and 50%, respectively, while it was 0% and 20% in those with androgen-negative livers (p<0.05). In contrast, the presence of androgen receptors within the tumor was not associated with a higher recurrence rate.Conclusions: These results show that only two thirds of hepatocellular carcinomas contained androgen receptors and that this feature was more frequent in small tumors. In addition, our data indicate that the presence of androgen receptors within the tumor does not imply a different outcome after surgical resection. In contrast, the presence of these receptors in the surrounding non-tumoral liver may be considered a risk factor for a higher incidence of disease recurrence.  相似文献   

2.
Tfm (testicular feminization) mutant mice lack functional androgen receptors. By studying liver tumor development in Tfm mice, we have shown that the greater susceptibility of male mice relative to female mice for liver tumor induction by N,N-diethylnitrosamine is androgen receptor-dependent. C57BL/6J normal and Tfm mutant mice were injected at 12 days of age with N,N-diethylnitrosamine (0.2 mumol/g, i.p.), and liver tumors were enumerated in 50-week-old animals. Normal males averaged 20 liver tumors per animal; Tfm males, 0.7; normal females, 0.6; and Tfm/+ heterozygous females, 1.5. The androgen receptor gene and the Tfm mutation are X chromosome linked. Because of random X chromosome inactivation, hepatocytes from Tfm/+ heterozygous female mice are mosaic with respect to the expression of mutant or wild-type receptors. To determine if testosterone acts directly as a liver tumor promoter, through the androgen receptor in preneoplastic hepatocytes, or by an indirect mechanism, we chronically treated these mosaic female mice with testosterone and measured the androgen receptor content of the resulting tumors. B6C3F1 Tfm/+ mosaic and +/+ wild-type female mice were injected i.p. at 12 days of age with N,N-diethylnitrosamine (0.1 mumol/g) and ovariectomized at 8 weeks of age. Half of the mice of each group subsequently received biweekly s.c. injections of testosterone (0.15 mg per mouse) for 30 weeks. Tumor multiplicity was the same for wild-type and Tfm/+ mosaic females treated with testosterone (31-32 tumors per animal at 38 weeks of age) and was increased relative to females not treated with testosterone (13-17 tumors per animal at 50 weeks of age). Testosterone treatment did not significantly increase the percentage of androgen receptor-positive tumors in Tfm/+ mosaic females: 58% of the tumors from Tfm/+ mosaic females treated with testosterone were receptor positive compared to 48% in Tfm/+ females not treated with testosterone and 92% in wild-type females treated with testosterone. Finally, the number of androgen receptors in the majority of liver tumors examined was greatly decreased relative to the surrounding normal liver tissue. We conclude that liver tumor promotion by testosterone requires a functional androgen receptor in the intact animal. However, this promotion is not cell autonomous; that is, the response of the preneoplastic hepatocyte is not dependent on the expression of functional receptor in the target cell.  相似文献   

3.
The effects of unsaturated fat and fiber (cellulose) on the growth of human colon cancer explanted to athymic nude mice was evaluated. Eighty-seven male nude mice bearing xenografts of human HT29 or WiDr colon cancer were divided into three groups of equal weight and tumor volume. Each group was fed one of three diets: normal fat/no fiber (N/N), high fat/no fiber (H/N) or high fat/high fiber (H/H). To equalize caloric intake, animals in the H/N group received 4 g of food per day and the other animals were fed 5 g of food per day. At sacrifice tumor volume and weight was recorded, and tumors were analyzed for protein and DNA content and ornithine decarboxylase activity. Tumor volume, weight, and protein were greater in the H/N group compared to the N/N group for both colon cancer cell lines. Tumor DNA content was greater in the HT29 H/N group compared to the N/N group (P<0.05) and tumor ornithine decarboxylase activity in the WiDr H/N group was greater than the N/N animals (P<0.002). The tumor growth-promoting effects of the high unsaturated fat diet were attenuated by the addition of fiber. Animal weight was higher in the H/N group compared to the N/N and H/H groups. This study suggested that a high-fat diet stimulated and fiber decreased the growth of human colon cancer explanted to athymic nude mice. The growth-promoting effects of a high-fat diet in colorectal cancer may be due in part to a circulating trophic factor since these tumors were remote from the large intestine.The study was support in part by grants IR29 CA45468(TJM) and CA50303(JPS) from the National Institutes of Health, and by the Research services the Veteran's Administration.  相似文献   

4.
Summary Sex hormones may play a role in colonic carcinogenesis, as evidenced by epidemiologic and experimental data showing different tumor rates in males and females. We investigated the effects of hormonal manipulation on tumor development and on androgen receptor binding in both colonic wall and experimentally induced tumors in male rats. Five of six groups, each with 40 animals, were given 10 weekly s.c. injections of azoxymethane (AOM), 7.5 mg/kg body weight. Group-I served as normal controls. Group-II received AOM only. Group-III was castrated 2 weeks prior to carcinogen treatment. Group-IV was castrated similarly and then hormone substituted with testosterone propionate. Group-V was chemically castrated with the anti androgen cyproterone acetate. Group-VI was castrated and given hormone vehicle. Scatchard analysis for androgen receptors in cytosol from normal colonic wall and tumor was performed with 3H-methyltrienolone as the ligand.Androgens were found to have an inhibitory effect on carcinogenesis: chemical castration increased colonic tumor development (P<0.05 for multiplicity), and testosterone administration produced a borderline statistically significant reduction in tumor incidence in surgically castrated rats (P<0.053), particularly in the right colon. Specific binding sites for androgen with high affinity and low capacity were found in the colonic wall of all groups. Receptor density was not altered by AOM administration, but increased after surgical castration. Receptor density was markedly lower in tumors than in normal colonic wall. Receptor binding sites in tumors were not altered by the various hormonal manipulations.Our study demonstrated that although cytoplasmic androgen receptors are present in colonic wall and in experimental tumors, AOM-induced colonic carcinogenesis appears to be only mildly affected by manipulation of androgens.Supported by a grant of the Deutsche Forschungsgemeinschaft Grant No. Iz 1/1-1, by the Ministry for Science and Research NRW, and by the Julia Baker Fund  相似文献   

5.
The results of this study confirm our previous report of increased androgen receptor expression in livers of female SUAH Wistar rats during development of liver tumours induced by diethylnitrosamine (DENA). In adult female rats not treated with DENA, removal of the ovary increased liver androgen receptor levels but testosterone did not further enhance the androgen receptor status of ovariectomized rats. In normal adult males the testis and/or testosterone maintained high levels of androgen receptors but oestrogen reduced them in castrated rats. Oestrogen receptor levels were not significantly changed in either males or females by gonadectomy. Treatment of female rats with DENA for 10 and 16 weeks increased liver androgen receptors but oestrogen receptors were only reduced by 16 weeks of DENA treatment, whether the rats were intact or ovariectomized. Concentrations of liver androgen receptors were increased in intact and castrated male rats by 10 and 16 weeks of DENA treatment, an increase not seen in the previous experiments. Oestrogen appeared to inhibit both the increases in liver androgen receptor expression and liver tumour development in rats treated with the weakly carcinogenic dose of 10 weeks of DENA. However, the full carcinogenic dose of 16 weeks of DENA increased liver androgen receptors and decreased oestrogen receptors in female rats regardless of sex-steroid status. Development of malignant hepatocellular carcinoma (HCC) was associated with both an increase in liver androgen receptors and a decrease in oestrogen receptors. Maintenance of relatively high levels of liver oestrogen receptors appeared to protect the liver against development of HCC.  相似文献   

6.
Abstract

Objective. Little is known about the expression of stem cell markers in normal liver and colorectal liver metastases (CLM). The aim of this paper is to assess whether patterns of stem cell marker expression differ between normal liver tissue and CLM and to determine whether a clinical model of liver regeneration induced by portal vein embolization (PVE) has any influence on these patterns of expression in both regenerated liver tissue and cancer. Materials and methods. Immunohistochemistry was used to provide semi-quantitative analysis of patterns of expression in tissue samples of liver and tumor tissue pre- and post-PVE in 23 patients with CLM. CD133, CD44 and Oct4 were studied. Results. There was no expression of CD133, CD44 or Oct4 in normal liver tissue before PVE but there was high expression of CD133 and CD44 in CLM. PVE had no significant influence on stem cell marker expression either in regenerated liver tissue or in tumor when compared with pre-PVE samples. Conclusion. Liver regeneration following PVE does not seem to involve stem cells. Stem cell marker expression by CLM supports the stem cell theory of carcinogenesis which is not influenced by PVE.  相似文献   

7.
An androgen-repressed human prostate cancer cell line, ARCaP, was established and characterized. This cell line was derived from the ascites fluid of a patient with advanced metastatic disease. In contrast to the behavior of androgen-dependent LNCaP and its androgen-independent C4-2 subline, androgen and estrogen suppress the growth of ARCaP cells in a dose-dependent manner in vivo and in vitro. ARCaP is tumorigenic and highly metastatic. It metastasizes to the lymph node, lung, pancreas, liver, kidney, and bone, and forms ascites fluid in athymic hosts. ARCaP cells express low levels of androgen receptor mRNA and prostate-specific antigen mRNA and protein. Immunohistochemical staining shows that ARCaP cells stain intensely for epidermal growth factor receptor, c-erb B2/neu, and c-erb B3. Staining is negative for chromogranin A and positive for bombesin, serotonin, neuron-specific enolase, and the c-met protooncogene (a hepatic growth factor/scatter factor receptor). ARCaP cells also secrete high levels of gelatinase A and B and some stromelysin, which suggests that this cell line may contain markers representing invasive adenocarcinoma with selective neuronendocrine phenotypes. Along with its repression of growth, androgen is also found to repress the expression of prostate-specific antigen in ARCaP cells as detected by a prostate-specific antigen promoter–β-galactosidase reporter assay. Our results suggest that the androgen-repressed state may be central to prostate cancer progression and that advanced prostate cancer can progress from an androgen-independent to an androgen-repressed state.  相似文献   

8.
Background. Cathepsin B, a lysosomal cysteine protease, has a major role in the mechanisms of tumor metastasis. The aim of the present work was to examine the correlation between cathepsin B activity and the metastatic potential of human pancreatic cancer. Methods. The primary cell line COLO 357 and the derivative tumor cell lines FG, L3.1, L3.2, L3.3, L3.4, and L3.5, which are characterized by progressively increasing metastatic potential, were injected intrasplenically in the athymic mice. Cathepsin B activity, metastasis, and ultrastructural characteristics were assessed. Results. An increased number of liver tumor nodules was observed with each subsequent intrasplenic inoculation (p=0.0001), associated with lymph node, splenic, and pancreatic involvement. Cathepsin B activity progressively increased (p=0.001) and was strongly positively correlated with the metastic potential. However, no correlation was found between the metastatic potential and ultrastructural characteristics. Conclusions. These findings further support the central role of cathepsin B in metastasis in a combined in vitro/in vivo model.  相似文献   

9.
Estrogen and androgen receptors within the liver have been reported to modulate the hepatic regenerative response to partial hepatectomy. Moreover, cyclosporine has several untoward effects that might occur as a consequence of alterations in sex hormone activity. To evaluate these questions the following experiments were performed. Estrogen and androgen receptors in cytosol were quantitated in livers of rats treated with cyclosporine or olive oil vehicle before and after partial hepatectomy or a sham operation. Ornithine decarboxylase activity and thymidine kinase activity were assessed as indices of hepatic regeneration. Preoperative levels of estrogen receptor activity in the hepatic cytosol were significantly greater in rats treated with cyclosporine as compared to vehicle treated controls (P<0.01). In contrast, preoperative levels of androgen receptor activity in the cyclosporine-treated and vehicle-treated animals were similar. Following partial hepatectomy, a reduction in the activity of both sex hormone receptors in the hepatic cytosol was observed and was compatible with results described previously in normal animals. Unexpectedly the preoperative levels of ornithine decarboxylase (P<0.01) and thymidine kinase activity (P<0.01) were significantly greater in the rats treated with cyclosporine as compared to the vehicle treated controls. As expected, ornithine decarboxylase activity (at 6 hr) and thymidine kinase activity (at 24 hr) rose and peaked in response to a partial hepatectomy but were significantly greater (P<0.05) in the rats treated with cyclosporine as compared to the vehicle. These results show that cyclosporine treatment causes an increase in the hepatic content of estrogen receptor activity that is associated with an enhanced potential for a regenerative response. These effects of cyclosporine treatment on the sex hormone receptor levels in liver may explain the mechanisms responsible for some of the untoward effects of treatment with this agent.Supported by research grants from the Veterans Administration project grant AM 29961, and from the NIDDK AM 32556, and from the NIAAA AA06601.  相似文献   

10.
When the human prostate cancer cell line, LNCaP 104-S, the growth of which is stimulated by physiological levels of androgen, is cultured in androgen-depleted medium for > 100 passages, the cells, now called LNCaP 104-R2, are proliferatively repressed by low concentrations of androgens. LNCaP 104-R2 cells formed tumors in castrated male athymic nude mice. Testosterone propionate (TP) treatment prevented LNCaP 104-R2 tumor growth and caused regression of established tumors in these mice. Such a tumor-suppressive effect was not observed with tumors derived from LNCaP 104-S cells or androgen receptor-negative human prostate cancer PC-3 cells. 5 alpha-Dihydrotestosterone, but not 5 beta-dihydrotestosterone, 17 beta-estradiol, or medroxyprogesterone acetate, also inhibited LNCaP 104-R2 tumor growth. Removal of TP or implantation of finasteride, a 5 alpha-reductase inhibitor, in nude mice bearing TP implants resulted in the regrowth of LNCaP 104-R2 tumors. Within 1 week after TP implantation, LNCaP 104-R2 tumors exhibited massive necrosis with severe hemorrhage. Three weeks later, these tumors showed fibrosis with infiltration of chronic inflammatory cells and scattered carcinoma cells exhibiting degeneration. TP treatment of mice with LNCaP 104-R2 tumors reduced tumor androgen receptor and c-myc mRNA levels but increased prostate-specific antigen in serum- and prostate-specific antigen mRNA in tumors. Although androgen ablation has been the standard treatment for metastatic prostate cancer for > 50 years, our study shows that androgen supplementation therapy may be beneficial for treatment of certain types of human prostate cancer and that the use of 5 alpha-reductase inhibitors, such as finasteride or anti-androgens, in the general treatment of metastatic prostate cancer may require careful assessment.  相似文献   

11.
Endocrine studies in men with pubertal macromastia (PM) have failed to reveal a hormonal abnormality to account for the disorder. As a result, it has been hypothesized that this form of gynecomastia may be a manifestation of a target organ abnormality. Because the syndromes of apparent androgen resistance, such as testicular feminization and Reifenstein's Syndrome, are associated with gynaecomastia, we examined skin fibroblasts cultured from men with pubertal macromastia for androgen receptor defects. We studied 12 men with PM and confirmed that plasma concentrations of testosterone, oestradiol, gonadotrophins, and prolactin, were all within the normal range; findings identical to those of a similar series of patients previously reported. Androgen receptor content (Ro) and binding affinity (Kd) in cultured areolar and pubic skin fibroblasts were measured using a dispersed, whole cell assay. Nineteen areolar cell lines from the 12 patients with PM were compared with 4 areolar cell lines from three normal men and 9 areolar cell lines from nine normal women. There was no difference in the mean androgen receptor content (approximately 10 000 sites/cell) or binding affinity (approximately 1 nM) between the patients' fibroblasts and those of the normal subjects. Similarly, there were no differences in these parameters when pubic skin fibroblast androgen receptors were used for the comparison. We conclude that, although PM may yet be due to a defect in breast tissue sensitivity to androgen, the disorder cannot be explained by abnormalities in fibroblast androgen receptor number or affinity.  相似文献   

12.
Summary Induction of neoplastic growth of murine stroma cells within the human tumor xenograft was observed after serial passage of CEA and 2-microglobulin producing human colonic SLu tumor xenografts in nu/nu BALB/c mice. Mouse tumors within the human tumor xenografts wre identified using specific immunohistologic staining techniques for mouse histocompatibility marker or human CEA. These mixed tumors could be distinguished from normal human tumor xenografts by a different relationship between development of the tumor marker in the serum and tumor size. We were able to establish transformed murine cells from human xenografts, either induced by SC injection of 1×106 tumor cells of the SLu cell line or by human SLu or mammary carcinoma tissue serially passaged in athymic animals. The established human and murine cell lines were characterized by cytogenetic methods. Transformed murine cells were then continuously passaged in tissue culture. The transformed mouse fibroblasts proved to possess tumorigenicity in nude mice. In the case of SLu-derived mouse tumor cells, tumors also developed in the immunocompetent BALB/c mice using 1×106 to 5×106 tumor cells for SC transplantation.  相似文献   

13.
To evaluate the potential effect of androgens on human colorectal cancer, the prevalence and concentration of cytosolic androgen receptors were analyzed in 23 rectal and 13 cecal adenocarcinomas by a hybrid radioligand assay. Androgen receptors were detected in nine of the rectal (39 percent) and five of the cecal tumors (38 percent). Androgen receptor levels demonstrated were low, ranging from three to 17 fmol/mg cytosol protein. Dissociation constants were 1 nM or less. The presence of androgen receptors was independent of age or sex of the patient, and of the state of histologic differentiation and Dukes' staging of the tumor. Androgen receptor prevalence was similar in mucosa adjacent to rectal and cecal adenocarcinomas and in mucosa from five of ten patients (50 percent) with diverticular disease. Our findings suggest that androgen dependency does not play a major role in endocrine control of the development of rectal cancer.  相似文献   

14.
Androgen receptors in hepatocellular carcinoma and surrounding parenchyma   总被引:12,自引:0,他引:12  
The androgen receptor content of normal human liver, hepatocellular carcinoma, and surrounding liver tissue was determined in patients with chronic liver disease. Androgen receptor was detected in all six normal livers obtained from 4 men and 2 women. The androgen receptor content in these 6 individuals ranged from 5.0 to 10.2 fmol/mg protein (Kd 10.6-31.8 X 10(-10) M). The livers from 2 patients with chronic active hepatitis and from 10 cirrhotic patients with hepatocellular carcinoma had detectable amounts of androgen receptor ranging from 2.0 to 14.8 fmol/mg protein (Kd 4.0-30.9 X 10(-10) M). Androgen receptor was found in the cytosol of 14 of 19 men with hepatocellular carcinoma. The titer ranged from 3.7 to 45.4 fmol/mg protein (Kd 3.2-21.4 X 10(-10) M). Hepatocellular carcinoma had a significantly higher concentration of androgen receptor than did the surrounding cirrhotic liver tissue. In 2 men and 1 woman, androgen receptor was detected in the cirrhotic liver but not in the tumor. In the remaining 3 men, both tumor and cirrhotic liver were negative for androgen receptor.  相似文献   

15.
Antiandrogens have sporadically been reported to exert antitumor activities in both pre-and post-menopausal breast cancer. To explore the possibility of using the pure antiandrogen flutamide (FLU) in breast cancer therapy, rats bearing DMBA-induced mammary tumors were treated with FLU, dihydrotestosterone (DHT), or FLU plus DHT. FLU was administered orally, at doses comparable to those used in the treatment of prostate cancer patients. FLU-treated animals had a significantly smaller average tumor area than controls from day 11 up to the end of the experiment (day 20). A similar reduction of tumor growth was observed in rats given DHT and in those treated with DHT plus FLU. Plasma levels of LH, FSH, P, 17-OH P, E2 and DHEA measured at the end of experiment did not differ between treated animals and controls. Results demonstrate that the antiandrogen FLU and the full androgen DHT exert similar inhibitory effects on the growth of dimethylbenz(a)anthracene (DMBA)-induced rat mammary tumors. Moreover, data show that plasma steroids levels are unaffected by FLU treatment. This finding rules out any antitumor effect dependent on the reduction of adrenal and gonadal steroidosynthesis, and makes it appear more likely that androgen receptors are involved in the antiproliferative effect of FLU.Abbreviations AR Androgen receptors - DHEA Dehydroepiandrosterone - DHT Dihydrotestosterone - DMBA 7,12-Dimethylbenz(a)anthracene - E 2 17-Estradiol - FLU Flutamide - P Progesterone - 17-OH P 17-Hydroxy-progesterone  相似文献   

16.
Aims/Methods: In the human liver, α-smooth muscle actin (ASMA) is present in smooth muscle of the vasculature, perisinusoidal cell (Ito cells), and myofibroblasts derived from perisinusoidal cells. In this study, we investigated ASMA-positive stromal cells and their relation to tumor fibrosis in 50 cholangiocarcinomas, 30 hepatocellular carcinomas, and 57 metastatic liver carcinomas.Results: Tumor fibrosis was much more extensive in cholangiocarcinomas and metastatic liver carcinomas than in metastatic liver carcinomas. ASMA immunoreactivity was prominent in the sinusoids surrounding cancer nodules and in the cancerous stroma, not in sinusoids remote from cancer nodules. ASMA-positive stromal cells were divisible into peritumoral ASMA-positive perisinusoidal cells and intratumoral ASMA-positive stromal cells. Both types of ASMA-positive cells were abundant in cholangiocarcinomas and metastatic liver carcinomas, but much more scanty in hepatocellular carcinomas. The number of both types showed a significant positive correlation with the degree of tumor fibrosis. The peritumoral ASMA-positive perisinusoidal cells were frequently in direct continuity with intratumoral ASMA-positive stromal cells in cholangiocarcinomas and metastatic liver carcinomas.Conclusions: These findings show that ASMA-positive stromal cells are related to tumor fibrosis in liver malignancies. Although direct evidence is lacking, the data suggest that, in cholangiocarcinomas and metastatic liver carcinomas, peritumoral ASMA-positive perisinusoidal cells transform into activated perisinusoidal cells (myofibroblasts), are incorporated into the tumor (intratumoral ASMA-positive stromal cells), and produce extracellular matrix proteins, that lead to tumor fibrosis. The scantly ASMA-positive cells in hepatocellular carcinomas may in part be responsible for the small amount of fibrosis in this tumor.  相似文献   

17.
肝癌组织及血清中细胞间粘附分子-1表达的研究   总被引:11,自引:1,他引:11  
目的研究细胞间粘附分子-1(intercelularadhesionmolecule-1,ICAM-1)作为判断肝癌发展程度及转移状态指标的可能性。方法以免疫组化的方法检测ICAM-1在肝癌组织和正常肝组织中的表达,观察了ICAM-1表达在细胞的定位。以点免疫印迹法测定不同患者血清和不同肝组织中ICAM-1的表达。分析ICAM-1表达与肿瘤生长转移状态、肿瘤特性的关系。结果肝癌细胞ICAM-1表达阳性(阳性率为800%),主要分布在细胞膜,正常肝细胞则为阴性。肝癌患者血清可溶性细胞间粘附分子-1(sICAM-1)水平高于正常人(P<001)及肝良性肿瘤患者(P<005),肝癌伴转移者高于无转移者(P<005)。肝癌组织中ICAM-1含量明显高于癌旁组织(P<001)及正常肝组织(P<001),而与肿瘤大小及有无包膜无关(P>005);转移组肝癌中ICAM-1的表达明显高于非转移组(P<005),两组癌旁组织中ICAM-1表达无差别(P>005)。结论血清及组织中ICAM-1的水平在一定程度上可以反映肝癌发展程度及转移状态,有可能作为预测肝癌转移复发的指标。  相似文献   

18.
Objective. To study the presence of androgen receptors in the synovial tissue of male and female patients with rheumatoid arthritis (RA) and matched healthy controls. Methods. Both site I (high affinity, low binding capacity) and site II (reduced affinity, higher binding capacity) androgen receptors were investigated in soluble and nuclear fractions of homogenized synovial samples, using the dextran-coated charcoal method. The finding of pure, high-affinity site I receptors in both fractions was considered indicative of androgen receptor positivity. In order to determine what type of synovial cell was positive for androgen receptors, cryosections of synovial tissues were immunostained with a specific monoclonal anti-androgen receptor antibody (MAb), using both immunofluorescence and immunoperoxidase techniques. Double immunostaining with this MAb and specific MAb directed toward different macrophage/granulocyte antigens was also performed. Results. Remarkable differences were found between male and female controls: Most males were positive for androgen receptors, and most females were negative. The femtomolar content of androgen receptor in the nuclear fraction was fairly constant, but the soluble fraction showed a higher femtomolar concentration in female RA patients than in controls of either sex, as well as in male RA patients compared with female RA patients. The androgen receptor-positive cells in both RA and control synovial cryosections were found by immunostaining to be macrophage-like synoviocytes, and were also found to be HLA-DR positive. Conclusions. The immunosuppressive action exerted by androgens might, at least in part, be mediated through their interaction with macrophage-like synoviocytes functioning as antigen-processing and antigen-presenting cells in rheumatoid synovia.  相似文献   

19.
20.
Using methods for cell lysis and fractionation which yield essentially quantitative recovery of rat prostate cancer cell cytosolic and nuclear androgen receptors, we examined androgen modulation of androgen receptor content of clonally derived prostate cancer cell lines. We showed that testosterone elicited a concentration-dependent 2.3-fold increase in T5 cell androgen receptor content which was maximum after 48 h and was maintained through at least 72 h of culture. Testosterone caused only a 1.4-fold elevation in D2 cell androgen receptor content which was maximum between 6 and 12 h of culture and was maintained through at least 72 h culture. In contrast, testosterone did not cause a change in C3 cell androgen receptor content. Cycloheximide inhibition showed that both the testosterone-mediated increase in and maintenance of basal prostate cancer cell androgen receptor content required protein synthesis. Because testosterone and the nonmetabolizable androgen R1881 were essentially equipotent as effectors of the increase in T5 cell androgen receptor content, findings using testosterone appear to represent maximum effects. RU 23908 antagonized both R1881 and testosterone promoted elevations of prostate cancer cell androgen receptor content. Effectiveness of RU 23908 was comparable to the relative binding affinity of R1881, testosterone and RU 23908 for androgen receptors. This implies that at least part of the androgen-promoted increase in prostate cancer cell androgen receptor content is mediated through the action of androgen receptors and suggests that androgen receptors may act as both cis and trans regulatory elements. The mechanisms which determine basal or androgen-modulated prostate cancer cell androgen receptor content remain to be elucidated.  相似文献   

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