Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0007097 (carcinoma)
 152,788 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Transcription of the lactoferrin gene is stimulated by estrogen in mouse uterus. To study direct estrogen regulation of this gene at the molecular level, we cloned and analyzed the 5'-flanking region of the mouse lactoferrin gene. Sequence analysis revealed a putative estrogen-responsive element (ERE) overlapping with a chicken ovalbumin up-stream promoter (COUP) element located at position -349 to -329 from the transcription initiation site. The ERE element differed from the consensus ERE sequence by one nucleotide at the second position of the 3' half of the element (G to A); the COUP element differed by one nucleotide from the chicken COUP element. Synthetic oligonucleotide containing the mouse lactoferrin COUP/ERE element was inserted into the reporter chloramphenicol acetyltransferase vector, then transiently transfected into human endometrium carcinoma RL95-2 cells to assess hormone responsiveness. We found that the COUP/ERE element confers estrogen action to both homologous and heterologous promoters. Nuclear proteins from diethylstilbestrol-treated mouse uteri and proteins from estrogen receptor expression vector-transfected RL95-2 whole cell extract bound in vitro to COUP/ERE element specifically, as assessed by band-shift assay. By using antibodies specific to the estrogen receptor and the COUP transcription factor, we demonstrated that both proteins were present in mouse uterine tissue and interacted specifically with the COUP/ERE element, as shown by the superband shift. Competition experiments with specific ERE or COUP oligonucleotides also confirmed the interaction between lactoferrin COUP/ERE element with the estrogen receptor and the COUP transcription factor. Therefore, we named this sequence mERM, the mouse lactoferrin estrogen response module.
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PMID:Estrogen response module of the mouse lactoferrin gene contains overlapping chicken ovalbumin upstream promoter transcription factor and estrogen receptor-binding elements. 158 12

Twelve postmenopausal women (54-93 years) with primary breast carcinoma were treated with tamoxifen due to infirmity or refusal to undergo surgery. Seven premenopausal patients (32-50 years) were given preoperative chemotherapy because of large tumors or inflammatory carcinoma. Fine-needle aspiration biopsy was used to procure tumor cells for diagnosis, hormone receptor determination and analysis of proliferation fraction. Aspirations were repeated every 3 months in the tamoxifen group and each month in patients receiving chemotherapy. Two patients who responded to tamoxifen had tumors with more than 75% estrogen receptor positive cells. A decreased proliferation fraction was observed in two tumors responding to tamoxifen. Eight patients, all with estrogen receptor positive tumors, had stable disease. Progressive disease was observed in two patients with less than 25% receptor positive cells. In these tumors the percentage of proliferating cells remained high during therapy. Objective response was recorded for six patients treated with chemotherapy. The clinical response was reflected in a decreased proliferation fraction. No correlation was observed between response and percentage of proliferating cells in the untreated tumor. The results suggest that analysis of tumor cell characteristics such as hormone receptor content and proliferation fraction can be used to predict and monitor response to endocrine treatment and chemotherapy in breast carcinomas.
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PMID:Analysis of hormone receptors and proliferation fraction in fine-needle aspirates from primary breast carcinomas during chemotherapy or tamoxifen treatment. 162 28

It is important to know the estrogen receptor rate in breast carcinoma management. Thus, an in vivo and atraumatic method would be very useful. Different ligands have been proposed for this. We present here the specific synthesis of 20E- and 20Z-17 alpha-iodovinyl-11 beta-methoxyestradiols and their biological characterization as estrogen receptor ligands. The two isomers were analysed by current chemical methods (NMR) and purified by HPLC. We carried out an in vivo study with 21-day-old Swiss mice to compare properties of the two ligands. The 20E-MIVE2 showed the best affinity for estrogen receptors, the uterus-to-blood ratio was 15-fold higher for the trans derivative. We enhanced the in vivo and in vitro properties of the 20E-MIVE2: the affinity constant was determined by Scatchard analysis, Kd = 16 x 10(-10) M, and biodistributions were performed with unlabelled estradiol pre-injection. We concluded that 20E-MIVE2 can be used for a feasibility study in patients with breast carcinoma.
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PMID:Estrogen receptor imaging with 17 alpha-[123I]iodovinyl-11 beta-methoxyestradiol (MIVE2)--Part I. Radiotracer preparation and characterization. 162 14

To investigate the relationship between the sex steroid receptor (estrogen receptor [ER] and progesterone receptor [PR]) status and the cell proliferation kinetics during the menstrual cycle in normal and neoplastic epithelium of the uterine cervix, immunohistochemical localization of ER, PR, and cell proliferation-associated antigen, Ki-67, was investigated in 35 normal cervical specimens, 3 condylomas, 26 cervical intraepithelial neoplasia (CIN) samples, and 22 invasive squamous carcinoma samples. The presence of human papillomavirus (HPV) DNA was also studied. In the normal cervix, basal cells were usually ER positive, PR negative, and Ki-67 negative throughout the menstrual cycle. Parabasal cells were ER positive and PR negative in the follicular phase, but ER negative and PR positive, and Ki-67 positive in the luteal phase, and Ki-67-positive cells increased in number in the luteal phase. In contrast, PR positivity was observed in the cells of condyloma (2 of 2 cases), CIN (19 of 26 cases), and invasive squamous carcinoma (13 of 22 cases) irrespective of the menstrual phase. Moreover, most neoplastic cells containing HPV DNA type 16/18 were ER negative, whereas several lesions containing HPV DNA type 31/33/35 were weakly ER positive. Many Ki-67-labeled cells were observed in the neoplastic lesions. These results suggest that reduced ER expression and increased PR expression are associated with the proliferation of normal cervical squamous epithelium, and this proliferation-related receptor status, which is probably induced by HPV infection, is usually expressed in neoplastic cervical squamous cells.
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PMID:Immunohistochemical analysis of estrogen receptors, progesterone receptors, Ki-67 antigen, and human papillomavirus DNA in normal and neoplastic epithelium of the uterine cervix. 165 7

Estrogen and progesterone receptors were immunohistochemically recorded from 426 cases of primary mammary carcinoma. Immunohistochemical detection was based on monoclonal antibodies to estrogen receptor (H222) and progesterone receptor (KD68). Immunohistochemical and biochemical tests were correlated to each other with significance (p less than 0.0001) for either receptor. Some of the histological parameters exhibited relationships with the immunohistochemical receptor status. Receptor positivity of lobular, mucoid, tubular, and papillary carcinomas was more frequent than that of ductal carcinoma, whereas that of medullary carcinoma fell below ductal cases. A straight forward correlation of statistical significance was found to exist between histological tumor grade and steroid hormone receptor status. Receptor positivity of carcinomas with sizeable stroma components proved to be more frequent than that of carcinomas with lower stroma levels. Steroid hormone receptors can be immunohistochemically identified from cytological specimens, as well, though some limiting factors are implied in the latter. Thirteen percent of fine-needle aspirates provided falsely negative steroid hormone receptor findings, as compared to histological biopsy. This problem was encountered primarily in cases of low receptor positivity and high stroma content of carcinoma, factors for which only minor amounts of cell material could be obtained from puncturing. Clinical follow-up checks and evaluation of survival data revealed the immunohistochemically determined steroid hormone receptor status to be of significant importance to prognostication (ER-ICA p less than 0.00001; PgR-ICA p = 0.004). The prognosis of patients with negative estrogen and progesterone receptors was found to be worse than that of patients with positive receptor status. These studies are likely to confirm immunohistochemical determination of steroid hormone receptors, using monoclonal antibodies, to be a reliable method of great prognostic importance.
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PMID:[Steroid hormone receptors in mammary carcinoma. Immunohistochemical detection and prognostic significance]. 165 32

Fifty-two human breast tumors were screened for the presence of DNA homology to mouse mammary tumor virus (MMTV) using molecularly cloned MMTV proviral genomic DNA probes and dot-blot hybridization. Seven patients were found to contain an entire provirus (gag, pol, env, and LTR positive at high stringency). Fifty percent (5/10) of patients having a first degree relative with breast carcinoma were found to have DNA homology to the gag-pol portion of the MMTV genome when hybridization and washing was performed at moderate (56C) stringency. Thirty-nine percent (7/18) of patients with any positive family history and 23 percent (8/34) of patients with a negative family history demonstrated homology under these parameters. Of the patients positive for gag-pol at moderate stringency, fewer had taken exogenous hormones than the sample group (20 percent vs 52 percent), more were parous (93 percent vs 68 percent), estrogen receptor positive (69 percent vs 48 percent), and male (13 percent vs 4 percent). At higher stringency (62C) no correlation to family history, hormone use or sex was detected, but positivity was noted among estrogen and progesterone receptor positive patients (67 percent vs 48 percent). Under lower stringency wash conditions, mismatched MMTV-related sequences are identified suggesting the existence of an endogenous gene with partial homology to MMTV. High stringency hybridization may identify a related retrovirus with significant homology to MMTV.
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PMID:Sequence homology of deoxyribonucleic acid to mouse mammary tumor virus genome in human breast tumors. 166 95

Methods of assessing tumor proliferation rates include mitosis counting, flow cytometry and thymidine labelling. While the former is inaccurate and poorly reproducible, the latter methods are time consuming and expensive to perform. Ki-67 is a monoclonal mouse antibody which has been shown to react with a nuclear antigen in proliferating cells. Frozen sections from 75 specimens of breast carcinoma were immunostained with this antibody using an immunoperoxidase technique. The percentage of tumor cells stained, the Ki-67 score, was then compared with a number of pathological and clinical variables in the patients concerned. A positive correlation was seen between the Ki-67 score and mitotic rate (r = 0.71); and a negative correlation was seen between Ki-67 score and estrogen receptor status (r = -0.4). Ki-67 immunostaining may represent a cheap and reproducible method of assessing proliferation rates of breast carcinomas which is applicable in routine laboratories. Further prospective studies are being undertaken to assess its contribution to prognosis.
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PMID:A comparison between Ki-67 antibody reactivity and other pathological variables in breast carcinoma. 166 11

Using the 21N polyclonal antibody, we immunohistochemically stained 314 primary breast carcinomas to identify those tumors overexpressing the c-erbB-2 oncoprotein and to ascertain the prognostic significance of this expression on disease-free and overall survival. Positive membrane staining was present in 52 (17%) of these carcinomas of which 7 (13%) were ductal carcinomas in situ. There was no significant relationship between c-erbB-2 positivity and (a) age at diagnosis, (b) menopausal status, (c) tumor size, (d) lymph node status, (e) estrogen receptor status, or (f) whether or not the patient had disseminated disease outside the axillary fields. However, c-erbB-2-positive tumors were significantly associated with poorer grade (P = 0.02). Patients who were positive for this oncoprotein had a shorter disease-free survival (P = 0.002) and reduced overall survival (P = 0.0001). Overexpression of this oncoprotein was predictive of a worse prognosis in lymph node-positive disease (P = 0.003) and in patients presenting with grade II tumors (P = 0.001). Stratifying the patients on the basis of estrogen receptor status suggested that c-erbB-2+/estrogen receptor-negative status was predictive of a poorer prognosis when compared with the other subgroups (P less than 0.001). Primary and recurrent tumor tissues were available from 42 of the 314 patients. Identical patterns of c-erbB-2 expression occurred in 95% of cases, arguing against a direct role for c-erbB-2 expression in the process of tumor dissemination. The high incidence of staining in ductal carcinomas in situ suggests that expression of this oncoprotein is an early event in tumorigenesis. Finally, multivariate analysis indicated that the c-erbB-2 oncoprotein was an independent prognostic indicator for overall survival in breast carcinoma patients.
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PMID:Prognostic significance of c-erbB-2 and estrogen receptor status in human breast cancer. 167 98

A polymerase chain reaction method was carried out to address the possible presence of estrogen receptor (ER) mutations in murine transformed cell lines. The segment of ER cDNA coding the C and D domains was amplified and cloned into pUC 19. Mammary carcinoma cell line (SC-3) did not show any mutation in this segment. However, the sequence analysis of ER in the Leydig cell line (B-1 F) revealed a single base change at acidic Glu-279 (GAA) to basic Lys-279 (AAA) compared with murine uterus ER cDNA. The biological significance of this mutation is discussed.
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PMID:A single nucleotide substitution in the D domain of estrogen receptor cDNA causes amino acid alteration from Glu-279 to Lys-279 in a murine transformed Leydig cell line (B-1 F). 167 3

An estrogen receptor-immunocytochemical assay (ER-ICA) was performed on frozen sections of 130 samples of human breast carcinoma. A standard dextran-coated charcoal assay (DCCA) was performed on the same samples. Concordance of results between the tests was 91%. The sensitivity and specificity of the ER-ICA, compared with the DCCA, were 92% and 89%, respectively. We describe the ER-ICA technique and review the literature regarding the use of the ER-ICA in evaluating breast cancer with respect to the agreement of results with the DCCA, the nature of discordant results, the ability to predict the clinical response to hormone therapy, and the ability to predict disease-free survival. The combined experience of many studies has shown that the ER-ICA is a highly specific and sensitive method for measuring the level of ERs in breast tumors with a high level of agreement with the DCCA. Early experience has suggested that the ER-ICA can predict the response to hormone therapy and disease-free survival, as well as or better than the DCCA. The evaluation of receptor heterogeneity, made possible by the ER-ICA, may enhance our ability to discriminate ER-positive tumors with a relatively high risk of recurrence.
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PMID:Immunocytochemical analysis of estrogen receptors in human breast carcinomas. Evaluation of 130 cases and review of the literature regarding concordance with biochemical assay and clinical relevance. 168 90


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