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Results for “PGR expression”

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PubMed2003

Protein expression of the glucocorticoid receptor in childhood acute lymphoblastic leukemia.

BACKGROUND AND OBJECTIVES: Early treatment response is a strong predictor for treatment outcome in childhood acute lymphoblastic leukemia (ALL), treated within the protocols of the Berlin-Frankfurt-Münster (BFM) study group. In the ALL-BFM trials, early treatment response is assessed by in vivo response to glucocorticoids (prednisone response), the molecular background of which is unknown. Initial in vivo resistance to glucocorticoid (GC) treatment in childhood ALL (prednisone-poor response) is associated with a dramatically shorter event-free survival than that found in GC-sensitive patients (prednisone-good responders). The intracellular effects of glucocorticoids are mediated by the glucocorticoid receptor (GR). The protein expression of the GR has been linked to in vivo and in vitro GC resistance in various diseases treated with GC. However, existing data are conflicting. RESULTS DESIGN AND METHODS: We performed a case-control study for prednisone response to investigate the association of in vivo GC resistance and GR protein expression in childhood ALL. GR expression was assessed using Western blot technology. RESULTS: The median relative GR protein expression of all patients was 0.87. Overall, we did not find different GR protein expression in PPR and PGR patients. GR protein expression was 0.91 in PGR patients versus 0.85 in PPR ones of in vivo GC resistance and GR expression. INTERPRETATION AND CONCLUSIONS: We conclude that the expression of GR is of minor importance for in vivo GC resistance in childhood ALL.

Adolescent↗

PubMed2006

Extraction-dependent effects of American ginseng (Panax quinquefolium) on human breast cancer cell proliferation and estrogen receptor activation.

HYPOTHESIS: Ginseng root extracts and the biologically active ginsenosides have been shown to inhibit proliferation of human cancer cell lines, including breast cancer. However, there are conflicting data that suggest that ginseng extracts (GEs) may or may not have estrogenic action, which might be contraindicated in individuals with estrogen-dependent cancers. The current study was designed to address the hypothesis that the extraction method of American ginseng (Panax quinquefolium) root will dictate its ability to produce an estrogenic response using the estrogen receptor (ER)-positive MCF-7 human breast cancer cell model. METHODS: MCF-7 cells were treated with a wide concentration range of either methanol-(alc-GE) or water-extracted (w-GE) ginseng root for 6 days. Cells were grown in media containing either normal or charcoal-stripped fetal calf serum to limit exposure to exogenous estrogen. Thus, an increase in MCF-7 cell proliferation by GE indicated potential estrogenicity. This was confirmed by blocking GE-induced MCF-7 cell proliferation with ER antagonists ICI 182,780 (1 nM) and 4-hydroxytamoxifen (0.1 microM). Furthermore, the ability of GE to bind ERalpha or ERbeta and stimulate estrogen-responsive genes was examined. RESULTS: Alc-GE, but not w-GE, was able to increase MCF-7 cell proliferation at low concentrations (5-100 microg/mL) when cells were maintained under low-estrogen conditions. The stimulatory effect of alc-GE on MCF-7 cell proliferation was blocked by the ER antagonists ICI 182,780 or 4-hydroxyta-moxifen. At higher concentrations of GE, both extracts inhibited MCF-7 and ER-negative MDA-MB-231 cell proliferation regardless of media conditions. Binding assays demonstrated that alc-GE, but not w-GE, was able to bind ERalpha and ERbeta. Alc-GE (50 microg/mL) also induced an approximate 2.5-fold increase in expression of the estrogen-responsive pS2 gene, as well as progesterone receptor (PgR) gene expression, whereas w-GE was without effect. CONCLUSION: These data indicate that low concentrations of alc-GE, but not w-GE, elicit estrogenic effects, as evidenced by increased MCF-7 cell proliferation, in a manner antagonized by ER antagonists, interactions of alc-GE with estrogen receptors, and increased expression of estrogen-responsive genes by alc-GE. Thus, discrepant results between different laboratories may be due to the type of GE being analyzed for estrogenic activity.

Breast Neoplasms↗

PubMedDate not supplied

Estrogen and progesterone receptors and telomerase enzyme immunohistochemical detection in gestational trophoblastic tumors.

The purpose of this study is to evaluate the immunohistochemical detection of telomerase enzyme and estrogen receptor (ER) and progesterone receptor (PGR) in gestational trophoblastic neoplasia (GTN) and its clinical significance. Formalin-fixed paraffin blocks for 30 patients (24 with molar pregnancy, 3 with choriocarcinoma, and 3 with placental site trophoblastic tumor) as cases and six products of conception samples from patients with incomplete abortion as controls were included in the study. Immunohistochemical detection of the telomerase catalytic protein and ER and PGR was carried out using streptavidin-biotin-peroxidase method. All control tissues were negative for telomerase and ER expression, while five of six were PGR positive. Significant positive telomerase expression was detected in all gestational trophoblastic tumors (three of six partial moles, 12 of 18 complete moles, three of three choriocarcinomas, and two of three placental site trophoblastic tumors). Nine of 24 molar pregnancies were followed by GTN. Molar pregnancies followed by GTN were associated with higher serum beta-hCG (human chorionic gonadotrophic hormone), larger uterine size for gestational age, negative ER expression, negative PGR expression, and positive telomerase expression. All patients with molar pregnancy with negative telomerase expression (9 of 24) showed spontaneous regression after evacuation. Positive telomerase expression and its immunohistochemical detection are associated with the development of GTN. Negative telomerase expression is highly predictive of postmolar spontaneous regression. Patients with molar pregnancies with negative telomerase expression can be saved the long-term follow-up. ER and PGR expression do not show a significantly different pattern in molar tissues, while negative expression is associated with developing GTN. Cautions on the use of postmolar hormonal contraception may be unjustified.

Adolescent↗

PubMed2004

Estrogen and progesterone receptor isoforms: clinical significance in breast cancer.

The identification and exploitation of biomarkers that may predict response to anti-cancer treatments has the capacity to revolutionize the way that patients with cancer are treated. In breast cancer, the estrogen receptor (ER) and the progesterone receptor (PgR) are known to have a significant predictive value in determining sensitivity to endocrine therapies. Tumor expression of ER or PgR is known to affect clinical outcome and this information is often used to determine a patient's optimal treatment regimen. However, the measurement of ER and PgR alone is more complex than originally thought and the impact of the recently identified isoforms of ER (ERalpha and ERbeta) and PgR (PgRA and PgRB), as well as several variant and mutant forms, upon the choice of treatment remains unclear. Therefore, ER and PgR expression alone are unlikely to determine a patient's optimal treatment regimen, particularly when the amount of 'cross-talk' between different pathways, such as the epidermal growth factor receptor pathway, is considered. In order to account for the complex cell-signaling environment that occurs in breast cancer, multifactorial techniques are needed to analyze tumor biomarker expression. The recent advances in genomic- or proteomic-based approaches has enabled molecular portraits of breast cancers to be painted, allowing biomarkers of response and prognosis to be identified and characterized more accurately than before. In the future, patients could be treated according to the molecular portrait of their tumor biomarker expression, maximizing the therapeutic benefit that each patient receives.

Biomarkers, Tumor↗

PubMed1991

Influence of the antioestrogen tamoxifen on normal breast tissue.

Immunohistochemical assays have been employed to study the expression of ER, PgR, EGFR and Ki67 immunostaining in normal breast tissue (n = 76). The expression of ER and PgR was highly variable in both pre and postmenopausal women and was characterised by large numbers of apparently negative cells. This was most evident for ER-ICA staining in tissues removed from premenopausal women. PgR levels were highest in the ducts of premenopausal women, while EGFR expression was elevated in both ducts and lobules. Ki67 expression was observed in less than 10% of all normal cells and was suppressed by the menopause in lobular tissue. Tamoxifen therapy (40 mg d-1) did not influence the expression of PgR, EGFR or Ki67 immunostaining in cancer associated normal tissue (n = 17). A significant increase, however, was observed in the mean percentage ER positivity in ductal tissue. No effect of duration of tamoxifen therapy was observed on the expression of the antigens studied.

Breast↗

PubMed1993

Estrogen and progesterone receptor detection in neoplastic and non-neoplastic thyroid tissues.

Previous reports have shown that estrogen and progesterone receptors (ER and PgR) are detectable in neoplastic and non-neoplastic thyroid tissues using a variety of techniques. However, differences in relative expression of ER and PgR according to tumor type have not been emphasized. To determine whether such differences occur and to assess clinicopathologic correlations, we have evaluated ER and PgR expression in sections of 64 thyroid lesions stained by indirect immunoperoxidase. The lesions studied included 39 papillary carcinomas, 3 follicular adenomas, 2 follicular carcinomas, 15 Hürthle cell tumors, 3 medullary carcinomas, and 2 multinodular goiters. Immunostaining was achieved using monoclonal antibodies H222 to ER and JZB39 to PgR. Additionally, the monoclonal antibodies D75p3 to ER and mPRI to PgR were also used in some cases. Overall, ER and/orPgR were detected in 26 of 64 lesions (40%) using any of the above antibodies. ER was identified in eight of 64 (12.5%) tumors that were all papillary carcinomas. No staining for ER was seen in follicular neoplasms, Hürthle cell tumors, or medullary carcinomas. PgR staining was present in 13 of 39 (33%) papillary carcinomas, 8 of 15 (53%) Hürthle cell tumors, 2 of 7 (28%) follicular tumors, and in none of 3 medullary carcinomas. Non-neoplastic thyroid tissue was negative for ER and PgR in all but one case in which weak staining for PgR was present adjacent to a follicular adenoma. There were no correlations between ER and/or PgR staining and age, gender, tumor size, presence of capsular or vascular invasion, or lymph node status in any tumor.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗

PubMed2000

Prognostic value of the type I growth factor receptors in a large series of human primary breast cancers quantified with a real-time reverse transcription-polymerase chain reaction assay.

We measured the expression of the type I growth factor receptor gene family [epidermal growth factor receptor (EGFR), c-erbB-2, c-erbB-3 and c-erbB-4] in a series of 365 unselected primary breast cancers. The expression was quantified with a real-time one-step reverse transcriptase-PCR (RT-PCR) assay, based upon the 5' nuclease activity of the Taq polymerase and using an Abi Prism 7700 Sequence Detector System (Perkin-Elmer, Courtaboeuf, France). c-erbB-3 and c-erbB-4 were positively correlated to each other (Spearman test) and negatively correlated to EGFR. EGFR and c-erbB-2 were inversely correlated to the presence of estradiol receptors (ER) and progesterone receptors (PgR), and positively correlated to the histoprognostic grading (HPG). Conversely, c-erbB-3 and c-erbB-4 were positively correlated to the presence of ER and PgR, and inversely correlated to the grading HPG. EGFR was inversely related (chi2 test) to the presence of ER and PgR, and positively associated with HPG. In contrast, both c-erbB-3 and c-erbB-4 were inversely related to HPG, and positively associated with the presence of ER and PgR. The expression level of EGFR and c-erbB-2 was significantly higher in ER- and PgR-negative tumors compared with ER- and PgR-positive tumors (Student's t test), and in tumors with higher grade compared with tumors with lower grade. The expression level of c-erbB-3 and c-erbB-4 was significantly higher in ER- and PgR-positive tumors compared with ER- and PgR-negative tumors and in tumors with lower grade compared with tumors with higher grade. In overall survival studies, Cox univariate analyses showed prognostic values of EGFR [> or = median; P = 0.026; risk ratio (RR), 1.6], c-erbB-3 (> or = median; P = 0.0093; RR, 0.58), c-erbB-4 (> or = median; P = 0.0024; RR, 0.52), HPG, node involvement, tumor diameter, ER, and PgR. In Cox multivariate analyses, tumor diameter, ER, and PgR had a prognostic value. In relapse-free survival studies, univariate analyses demonstrated prognostic values of tumor diameter, node involvement, and c-erbB-4 (P = 0.015; RR, 0.65). These three parameters maintained their prognostic value in multivariate analyses (c-erbB-4, P = 0.035; RR, 0.67). This study confirms that EGFR expression and c-erbB-2 expression are markers of tumor aggressiveness in breast cancer. Conversely, we demonstrate that c-erbB-3 and c-erbB-4 elevated expressions are associated with a better prognosis.

Adult↗

PubMed1991

Variant human breast tumor estrogen receptor with constitutive transcriptional activity.

Since progesterone receptor (PgR) is normally induced by estrogen, breast cancer lacking estrogen receptor (ER) would also be expected to lack PgR. However, a small percentage of breast cancers are ER- yet PgR+. These tumors might possess an ER which is defective in estrogen binding but is still functional in stimulating estrogen-responsive genes such as PgR. We have now detected such a variant, lacking exon 5 of the hormone-binding domain, using complementary DNA amplified by the polymerase chain reaction. This variant was the predominate ER RNA expressed in three ER-/PgR+ tumors. Furthermore, the variant ER constitutively activates transcription of a normally estrogen-dependent gene construct in yeast cells. The variant ER could explain the expression of PgR in certain tumors and have therapeutic implications.

Base Sequence↗

PubMed2000

Human meningiomas: immunohistochemical localization of progesterone receptor and heat shock protein 27 and absence of estrogen receptor and PS2.

Formalin-fixed, paraffin-embedded tumor specimens from 64 human meningiomas of various histologic types were immunostained using a streptavidin-peroxidase method and monoclonal antibodies for estrogen receptors (ER) and progesterone receptors (PgR) and hormone-induced proteins PS2 and heat shock protein 27 (Hsp27). The immunohistochemical analysis was scored in a semiquantitative fashion incorporating both the intensity and distribution of specific staining (score). Strong PgR nuclear immunoreactivity (mean score, 54.2) was observed in 51 of 64 meningiomas (80%). Meningiomas with atypical features were negative for PgR. Low Hsp27 cytoplasmic immunoreactivity (mean score, 9.8)--irrespective of histologic type--was observed in 26 of 64 meningiomas (40%). Whor1 formations in transitional meningiomas were Hsp27-positive. Hsp27 immunoreactivity was observed in tumor blood vessels. All neoplasms were negative for ER and PS2. Normal arachnoid tissue was positive for PgR and negative for ER, PS2, and Hsp27. Compared with previously reported data on gliomas, the results of this study indicate that meningiomas show a clear out difference concerning the expression of PgR and Hsp27.

Estrogens↗

PubMed1992

Changes in epidermal growth factor receptor expression and response to ligand associated with acquired tamoxifen resistance or oestrogen independence in the ZR-75-1 human breast cancer cell line.

We have examined the expression of receptors for epidermal growth factor (EGFR) by the ZR-75-1 human breast cancer cell line and tamoxifen resistant (ZR-75-9al 8 microM) and oestrogen independent/tamoxifen sensitive (ZR-PR-LT) variants. The parent line expressed a single class of high affinity binding sites (4,340 +/- 460 receptors/cell; Kd 0.23 +/- 0.04 nM). ZR-75-9al 8 microM cells, routinely maintained in medium containing 8 microM tamoxifen, were negative for oestrogen receptor (ER) and progesterone receptor (PGR) and expressed a markedly increased number of EGFR (14,723 +/- 2116 receptors/cell). Receptor affinity was unchanged. Time dependent reversal of the tamoxifen resistant phenotype was accompanied by a return to ER and PGR positivity and a fall in EGFR numbers to parent cell levels. In contrast ZR-PR-LT cells had a greatly reduced EGFR content (803 +/- 161 receptors/cell) accompanying elevated PGR numbers. Pre-treatment of these cells with suramin or mild acid stripping failed to expose receptors which may have been occupied by endogenously produced ligand. Increased proliferation of ZR-75-1 cells treated with EGFR (0.01-10 ng ml-1) was only observed in serum-free medium lacking insulin and oestradiol. Under these conditions untreated cells failed to proliferate. Both variant lines continued to proliferate in serum free medium in the absence or presence of insulin and oestradiol but failed to respond to exogenous EGF.

Breast Neoplasms↗

PubMed1999

Bcl-2 expression on fine-needle aspirates from primary breast carcinoma: correlation with other biologic factors.

BACKGROUND: The bcl-2 gene encodes for a protein that is involved in cell death regulation. It frequently is expressed in breast tumors, in which it is associated with favorable prognostic factors. It has been suggested that bcl-2 also may act as a modulator of response to chemotherapy and/or endocrine therapy. Because fine-needle aspiration (FNA) biopsy has been established as a reliable method for the diagnosis and biologic characterization of breast carcinoma, we assessed Bcl-2 expression on FNAs from primary breast carcinoma and evaluated its correlations with other prognostic variables. METHODS: Bcl-2, estrogen receptor (ER), progesterone receptor (PgR), p53 protein expression, and Ki-67 growth fraction were evaluated by immunocytochemistry on FNAs from 130 patients with primary breast carcinoma. Nuclear cytologic grade was assessed on FNA smears. RESULTS: Bcl-2 was expressed in 99 of 130 FNAs (76%). Bcl-2 expression was correlated with positive ER (P < 0.001) and PgR (P < 0.001) status and inversely correlated with p53 (P = 0.0036), Ki-67 (P = 0.0073), and nuclear cytologic grade (P < 0.001). CONCLUSIONS: Bcl-2 expression, evaluated by immunocytochemistry on FNAs from primary breast carcinoma, correlates with favorable prognostic features such as ER and PgR expression, p53 negativity, a low Ki-67 index, and high tumor differentiation. These results are in agreement with those found on histologic samples. As FNA biopsy is used increasingly as a primary tool in the diagnosis of breast carcinoma, Bcl-2 evaluation by immunocytochemistry on FNA may provide, in addition to other biologic variables, useful information for prognostic and predictive purposes, particularly in patients considered to be candidates for neoadjuvant treatments. Cancer (Cancer Cytopathol)

Biomarkers, Tumor↗

PubMed2005

Neuroendocrine consequences of prenatal androgen exposure in the female rat: absence of luteinizing hormone surges, suppression of progesterone receptor gene expression, and acceleration of the gonadotropin-releasing hormone pulse generator.

Preovulatory GnRH and LH surges depend on activation of estrogen (E2)-inducible progesterone receptors (PGRs) in the preoptic area (POA). Surges do not occur in males, or in perinatally androgenized females. We sought to determine whether prenatal androgen exposure suppresses basal or E2-induced Pgr mRNA expression or E2-induced LH surges (or both) in adulthood, and whether any such effects may be mediated by androgen receptor activation. We also assessed whether prenatal androgens alter subsequent GnRH pulsatility. Pregnant rats received testosterone or vehicle daily on Embryonic Days 16-19. POA-hypothalamic tissues were obtained in adulthood for PgrA and PgrB (PgrA+B) mRNA analysis. Females that had prenatal exposure to testosterone (pT) displayed reduced PgrA+B mRNA levels (P < 0.01) compared with those that had prenatal exposure to vehicle (pV). Additional pregnant animals were treated with vehicle or testosterone, or with 5alpha-dihydrotestosterone (DHT). In adult ovariectomized offspring, estradiol benzoate produced a 2-fold increase (P < 0.05) in PgrA+B expression in the POA of pV females, but not in pT females or those that had prenatal exposure to DHT (pDHT). Prenatal testosterone and DHT exposure also prevented estradiol benzoate-induced LH surges observed in pV rats. Blood sampling of ovariectomized rats revealed increased LH pulse frequency in pDHT versus pV females (P < 0.05). Our findings support the hypothesis that prenatal androgen receptor activation can contribute to the permanent defeminization of the GnRH neurosecretory system, rendering it incapable of initiating GnRH surges, while accelerating basal GnRH pulse generator activity in adulthood. We propose that the effects of prenatal androgen receptor activation on GnRH neurosecretion are mediated in part via permanent impairment of E2-induced PgrA+B gene expression in the POA.

Androgens↗

PubMed1994

Steroid hormone receptors in three human gastric cancer cell lines.

Steroid hormone receptors in three human gastric adenocarcinoma cell lines and their transplanted tumors (except nontumorigenic KATO-III) in nude mice were determined by dextran-coated charcoal assay. Progesterone receptors (PgR) were found in all cell lines, transplanted NUGC-3, and AZ 521 tumors. Estrogen receptors (ER) were found in KATO-III cells, transplanted NUGC-3, and AZ 521 tumors, whereas glucocorticoid receptors (GR) were found only in NUGC-3 tumor and no androgen receptor was found in any cell lines or transplanted tumors. Since NUGC-3 cells had ER, PgR, and GR, it was used for the study of the effects of steroid hormones on growth. The results showed the cell cycle phase distributions and growth rate of transplanted tumors were similar in hormone-treated and nontreated groups. The persistent expression of PgR in gastric cancer cell lines and tumors, and the slight increase of tumor volumes in the progesterone-treated group suggests that progesterone and its receptors may be important in the pathogenesis of gastric cancer, but their biological function remains to be elucidated.

Adenocarcinoma↗

PubMed2006

Radiological features and pathological-biological correlations in 348 women with breast cancer under 35 years old.

The aim of this study was to present mammography and ultrasound features, and accuracy, in 348 young women (under 35 years old) with breast cancer, and to determine whether such features could be correlated with pathological and biological factors. We performed a retrospective review of the radiological, pathological and biological features of women under 35 years old with breast cancer who were seen in our institute between January 2000 and December 2002. A total of 348 women were analysed. The sensitivity of mammography was 84.9% and that of ultrasound was 88%. There is a statistically significant positive correlation between the high sensitivity of ultrasound and the histology type (P=0.004) as well as the expression of PgR (P=0.01). Also, there is a correlation between the sensitivity of mammography and the histology type (P=0.004). Microcalcifications are associated with age (P=0.05) and overexpression of HER2/neu (P=0.007). Ultrasound may be the appropriate initial imaging test for symptomatic young women, and mammography may be useful in confirming the features, although there was no significant difference in the accuracy of the two tests. Histological and biological profiles may be correlated with imaging sensitivity.

Adult↗

PubMed1996

Multiple splicing variants of the estrogen receptor are present in individual human breast tumors.

Transcript variants of the estrogen receptor (ER) were investigated in 109 primary breast tumors using reverse transcription-polymerase chain reaction (RT-PCR) and primers allowing analysis of each internal exon. A high incidence of different ER variants was observed, each individual tumor often manifesting multiple variants coexisting with corresponding wildtype (wt) ER. These variants, by sequence analysis confirmed to represent exon splicing deletions, included ER deltaE2 (found in 41% of the tumors examined), ER deltaE3 (74%), ER deltaE4 (72%), ER deltaE5 (66%), and ER deltaE7 (88%). No evidence of transcripts lacking exon 6 was found, although a ER deltaE5,7 variant manifesting simultaneous deletion of exons 5 and 7 was observed. The presence of specific ER variants was not significantly correlated to the status of ER and progesterone receptor (PgR) protein expression, as assessed by routine analysis, although a trend towards a higher incidence of ER deltaE3 and increased expression of ER deltaE7 in ER+/PgR- tumors was observed, suggesting a dominant inhibitory effect on normal ER function to be involved. Moreover, ER deltaE4 was more common in ER+ tumors, possibly due to a cytoplasmic sequestring of this variant lacking a nuclear localization sequence. The presence of ER variants was not associated to clinicopathological variables, and equally frequent in tumors from patients having recurred or remained recurrence-free during adjuvant tamoxifen therapy. In conclusion, although ER splicing variants are abundant in breast cancer, the present study provides no evidence for a direct role of these ER variants in tumor development and tamoxifen resistance. It remains possible, however, that minor cell clones within the tumor, undetected by analysis of tumor homogenates, displaying extreme difference in content of ER variants, could be selected for during therapy or metastasis.

Adult↗

PubMed2003

Oestrogen receptor-mediated modulation of the EGFR/MAPK pathway in tamoxifen-resistant MCF-7 cells.

Oestrogen receptor (ER) levels are usually maintained on acquisition of tamoxifen resistance in the clinic, however, tumour re-growth is associated with increased expression of epidermal growth factor receptor (EGFR) and activation of the mitogen activated protein kinase (MAPK) pathway. In the present study we have used the ER down-regulator fulvestrant ('Faslodex') to investigate the influence of the ER on growth of a tamoxifen-resistant (TAM-R) human breast cancer cell line. Expression levels of ER mRNA and protein were equivalent in parental wild-type MCF-7 (WT) and TAM-R cells. Fulvestrant eliminated ER protein expression and inhibited proliferation in both cell lines. The growth inhibitory effects of fulvestrant were associated with a decrease in basal EGFR, c-erbB2 and ERK1/2 activity in TAM-R but not WT cells. ER functionality as determined by oestrogen response element (ERE)-luciferase reporter activity and expression of PgR, pS2 and transforming growth factor alpha (TGFalpha) was significantly reduced in TAM-R compared to WT cells and was further decreased by fulvestrant treatment in both cell lines. Epidermal growth factor (EGF) and TGFalpha significantly increased EGFR/MAPK pathway activity in both cell lines. Ligand-induced EGFR/MAPK activation promoted TAM-R cell growth in both the absence and presence of fulvestrant, whereas no proliferative activity was observed under the same conditions in WT cells. These results suggest that the ER modulates EGFR/MAPK signalling efficiency in TAM-R cells possibly through the regulation of TGFalpha availability. This effect may be overcome by the action of exogenous EGFR ligands, which strengthen EGFR/MAPK signalling activity to generate endocrine-insensitive cell growth.

Antineoplastic Agents, Hormonal↗

PubMedDate not supplied

Immunohistochemical demonstration of growth factors, TGF-alpha, TGF-beta, IGF-I and neu oncogene product in benign and malignant human breast tissues.

The expression of growth factors, TGF-alpha, TGF-beta, IGF-I and neu oncogene product was studied immunohistochemically in the tissue of 120 benign and malignant human breasts. Growth factors were found only in benign or malignant mammary epithelial cells and not in stromal cells. Normal and benign lesions were found to be negative for reactivity with each antibody. Carcinoma in situ and invasive breast carcinomas demonstrated a significantly higher percentage of stained cells than that observed in benign lesions; forty (49%) of 82 invasive carcinomas were positive for TGF-alpha, 31 (38%) for TGF-beta, 31 (38%) for IGF-I and 34 (41%) for neu product. No overall correlations were found between expression of each growth factor and the clinical stage or degree of histologic differentiation of the carcinomas. A significant positive correlation was observed between ER status and IGF-I expression and between PgR status and TGF-beta expression. In the majority of the carcinomas, co-expression between TGF-alpha, TGF-beta and IGF-I was observed; the percentage of cases with parallel positive or negative expression of two growth factors was as follows; TGF-alpha - TGF-beta (70%), TGF-alpha - IGF-I (57%), TGF-beta - IGF-I (71%). The concomitant expression of TGF-alpha and neu oncogene product in cell surface was also observed. The relapse-free intervals of the patients were studied in association with expression of each growth factor. TGF-beta-positive tumors showed a significantly better prognosis than TGF-beta - negative tumors (within the first 2 years of observation). However, TGF-alpha, IGF-I and neu overexpression showed no effect on the prognosis of the patients.

Adult↗

PubMed1999

Obesity affects expression of progesterone receptors and node metastasis of mammary carcinomas in postmenopausal women without a family history.

Possible relationships between risk factors, such as obesity and a family history of breast cancer, and prognostic factors of mammary carcinomas were investigated by examining the body mass index of patients and the expression of estrogen (ER) and progesterone receptors (PgR), c-erbB-2 and p53, grade of histology, size of tumors and nodal status of mammary carcinomas. There was no significant difference in the body mass index of premenopausal patients either with or without a family history. For postmenopausal patients, the body mass index was significantly low in patients with a family history compared with patients without a family history. In premenopausal patients with or without a family history and in postmenopausal patients with a family history, there was no significant difference in the body mass index regardless of the mammary carcinoma prognostic factor, such as expression of ER, PgR, c-erbB-2 and p53, grade of histology, size of tumors and nodal status. However, in postmenopausal patients without a family history, body mass index was significantly high for patients with mammary carcinomas that had PgR expression and node metastasis. These results suggest that obesity may affect the PgR status and nodal status of mammary carcinomas in postmenopausal patients without a family history.

Body Mass Index↗