Browsing by Subject "estrogen receptor"

Now showing 1 - 6 of 6
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    Aggressive breast cancer in western Kenya has early onset, high proliferation, and immune cell infiltration
    (Biomed Central, 2016-03) Sawe, Rispah T.; Kerper, Maggie; Badve, Sunil S.; Li, Jun; Sandoval-Cooper, Mayra; Xie, Jingmeng; Shi, Zonggao; Patel, Kirtika; Chumba, David; Ofulla, Ayub; Prosperi, Jenifer; Taylor, Katherine; Stack, M. Sharon; Mining, Simeon; Littlepage, Laurie E.; Pathology and Laboratory Medicine, School of Medicine
    Background Breast cancer incidence and mortality vary significantly among different nations and racial groups. African nations have the highest breast cancer mortality rates in the world, even though the incidence rates are below those of many nations. Differences in disease progression suggest that aggressive breast tumors may harbor a unique molecular signature to promote disease progression. However, few studies have investigated the pathology and clinical markers expressed in breast tissue from regional African patient populations. Methods We collected 68 malignant and 89 non-cancerous samples from Kenyan breast tissue. To characterize the tumors from these patients, we constructed tissue microarrays (TMAs) from these tissues. Sections from these TMAs were stained and analyzed using immunohistochemistry to detect clinical breast cancer markers, including estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor 2 receptor (HER2) status, Ki67, and immune cell markers. Results Thirty-three percent of the tumors were triple negative (ER-, PR-, HER2-), 59 % were ER+, and almost all tumors analyzed were HER2-. Seven percent of the breast cancer patients were male, and 30 % were <40 years old at diagnosis. Cancer tissue had increased immune cell infiltration with recruitment of CD163+ (M2 macrophage), CD25+ (regulatory T lymphocyte), and CD4+ (T helper) cells compared to non-cancer tissue. Conclusions We identified clinical biomarkers that may assist in identifying therapy strategies for breast cancer patients in western Kenya. Estrogen receptor status in particular should lead initial treatment strategies in these breast cancer patients. Increased CD25 expression suggests a need for additional treatment strategies designed to overcome immune suppression by CD25+ cells in order to promote the antitumor activity of CD8+ cytotoxic T cells.
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    ESR1 and PGR polymorphisms are associated with estrogen and progesterone receptor expression in breast tumors
    (American Physiological Society, 2016-09-01) Hertz, Daniel L.; Henry, N. Lynn; Kidwell, Kelley M.; Thomas, Dafydd; Goddard, Audrey; Azzouz, Faouzi; Speth, Kelly; Li, Lang; Banerjee, Mousumi; Thibert, Jacklyn N.; Kleer, Celina G.; Stearns, Vered; Hayes, Daniel F.; Skaar, Todd C.; Rae, James M.; Medicine, School of Medicine
    Hormone receptor-positive (HR+) breast cancers express the estrogen (ERα) and/or progesterone (PgR) receptors. Inherited single nucleotide polymorphisms (SNPs) in ESR1, the gene encoding ERα, have been reported to predict tamoxifen effectiveness. We hypothesized that these associations could be attributed to altered tumor gene/protein expression of ESR1/ERα and that SNPs in the PGR gene predict tumor PGR/PgR expression. Formalin-fixed paraffin-embedded breast cancer tumor specimens were analyzed for ESR1 and PGR gene transcript expression by the reverse transcription polymerase chain reaction based Oncotype DX assay and for ERα and PgR protein expression by immunohistochemistry (IHC) and an automated quantitative immunofluorescence assay (AQUA). Germline genotypes for SNPs in ESR1 (n = 41) and PGR (n = 8) were determined by allele-specific TaqMan assays. One SNP in ESR1 (rs9322336) was significantly associated with ESR1 gene transcript expression (P = 0.006) but not ERα protein expression (P > 0.05). A PGR SNP (rs518162) was associated with decreased PGR gene transcript expression (P = 0.003) and PgR protein expression measured by IHC (P = 0.016), but not AQUA (P = 0.054). There were modest, but statistically significant correlations between gene and protein expression for ESR1/ERα and PGR/PgR and for protein expression measured by IHC and AQUA (Pearson correlation = 0.32–0.64, all P < 0.001). Inherited ESR1 and PGR genotypes may affect tumor ESR1/ERα and PGR/PgR expression, respectively, which are moderately correlated. This work supports further research into germline predictors of tumor characteristics and treatment effectiveness, which may someday inform selection of hormonal treatments for patients with HR+ breast cancer.
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    Loss of ERα and FOXA1 expression in a progression model of luminal type breast cancer: Insights from PyMT transgenic mouse model
    (Spandidos Publications, 2010-11) McCune, Kasi; Mehta, Rutika; Thorat, Mangesh A.; Badve, Sunil; Nakshatri, Harikrishna
    The classification of breast cancers into multiple molecular subtypes has necessitated the need for biomarkers that can assess tumor progression and the effects of chemo-preventive agents on specific breast cancer subtypes. The goal of this study was to identify biomarkers whose expression are altered along with estrogen receptor α (ERα) in the polyoma middle-T antigen (PyMT) transgenic model of breast cancer and to investigate the chemopreventive activity of phenethyl isothiocyanate (PEITC). The diet of PyMT female mice was fortified with PEITC (8 mmol/kg) and the mammary streak and/or gross tumors and metastases in lungs were subjected to immunohistochemical analyses for ERα, FOXA1, and GATA-3. FOXA1 is associated with luminal type A cancers, while GATA-3 is a marker of luminal progenitor cell differentiation. In both control and PEITC-treated groups, there was a progressive loss of ERα and FOXA1 but persistence of GATA-3 expression indicating that the tumors retain luminal phenotype. Overall, the PyMT induced tumors exhibited the entire gamut of phenotypes from ERα+/FOXA1+/GATA-3+ tumors in the early stage to ERα±/FOXA1−/GATA-3+ in the late stage. Thus, PyMT model serve as an excellent model for studying progression of luminal subtype tumors. PEITC treated animals had multiple small tumors, indicating delay in tumor progression. Although these tumors were histologically similar to those in controls, there was a lower expression of these biomarkers in normal luminal cells indicating delay in tumor initiation. In in vitro studies, PEITC depleted AldeFluor-positive putative stem/progenitor cells, which may partly be responsible for the delay in tumor initiation.
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    NF-κB activation and interleukin 6 production in fibroblasts by estrogen receptor-negative breast cancer cell-derived interleukin 1α
    (National Academy of Sciences, 1998-06-09) Bhat-Nakshatri, Poornima; Newton, Thomas R.; Goulet, Robert; Nakshatri, Harikrishna
    Several angiogenic factors and extracellular matrix-degrading enzymes that promote invasion and metastasis of cancer are produced by stromal fibroblasts that surround cancer cells. The expression of genes that code for some of these proteins is regulated by the transcription factor NF-κB. In this report, we demonstrate that conditioned medium (CM) from estrogen receptor (ER)-negative but not ER-positive breast cancer cells induces NF-κB in fibroblasts. In contrast, CM from both ER-positive and ER-negative breast cancer cells induces NF-κB in macrophages and endothelial cells. NF-κB activation in fibroblasts was accompanied by induction of interleukin 6 (IL-6) and urokinase plasminogen activator (uPA), both of which promote angiogenesis and metastasis. A survey of cytokines known for their ability to induce NF-κB identified IL-1α as the factor responsible for NF-κB activation in fibroblasts. Analysis of primary breast carcinomas revealed the presence of IL-1α transcripts in majority of lymph node-positive breast cancers. These results along with the known role of IL-1α and IL-6 in osteoclast formation provide insight into the mechanism of metastasis and hypercalcemia in advanced breast cancers.
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    Prognosis of hormone-dependent breast cancers: implications of the presence of dysfunctional transcriptional networks activated by insulin via the immune transcription factor T-bet
    (American Association for Cancer Research, 2010-01-15) McCune, Kasi; Bhat-Nakshatri, Poornima; Thorat, Mangesh A; Nephew, Kenneth P; Badve, Sunil; Nakshatri, Harikrishna
    Estrogen receptor alpha (ERα)-positive breast cancers that co-express trans cription factors GATA-3 and FOXA1 have a favorable prognosis. These transcription factors form an autoregulatory hormonal network that influences estrogen responsiveness and sensitivity to hormonal therapy. Disruption of this network may be a mechanism whereby ERα positive breast cancers become resistant to therapy. The transcription factor T-bet is a negative regulator of GATA-3 in the immune system. In this study, we report that insulin increases the expression of T-bet in breast cancer cells, which correlates with reduced expression of GATA-3, FOXA1 and the ERα:FOXA1:GATA-3 target gene GREB-1. The effects of insulin on GATA-3 and FOXA1 could be recapitulated through overexpression of T-bet in MCF-7 cells (MCF-7-T-bet). Chromatin immunoprecipitation assays revealed reduced ERα binding to GREB-1 enhancer regions in MCF-7-T-bet cells and in insulin treated MCF-7 cells. MCF-7-T-bet cells were resistant to tamoxifen in the presence of insulin and displayed prolonged ERK and AKT activation in response to epidermal growth factor treatment. ERα-positive cells with intrinsic tamoxifen resistance as well as MCF-7 cells with acquired tamoxifen and fulvestrant resistance expressed elevated levels of T-bet and/or reduced levels of FOXA1 and GATA-3. Analysis of publicly available databases revealed ERα-positive/T-bet-positive breast cancers expressing lower levels of FOXA1 (p=0.0137) and GATA-3 (p=0.0063) compared to ERα-positive/T-bet-negative breast cancers. Thus, T-bet expression in primary tumors and circulating insulin levels may serve as surrogate biomarkers to identify ERα-positive breast cancers with a dysfunctional hormonal network, enhanced growth factor signaling, and resistance to hormonal therapy.
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    TFAP2C Expression in Breast Cancer - Correlation with Overall Survival Beyond 10 Years of Initial Diagnosis
    (Springer, 2015-08) Perkins, Susan M.; Bales, Casey; Vladislav, Tudor; Althouse, Sandra; Miller, Kathy D.; Sandusky, George; Badve, Sunil; Nakshatri, Harikrishna; Department of Surgery, IU School of Medicine
    Recurrence and death in a significant number of patients with ERα-positive breast cancer occurs 10–20 years after diagnosis. Prognostic markers for late events have been more elusive. TFAP2C (AP2γ) regulates the expression of ERα, the ERα pioneer factors FOXA1 and GATA3, and controls ERα-dependent transcription. The purpose of this investigation is to determine the long-term prognostic value of TFAP2C. A tissue microarray (TMA) consisting of breast tumors from 451 patients with median follow-up time of 10.3 years was created and tested for the expression of TFAP2C by immunohistochemistry. Wilcoxon Rank-Sum and Kruskal–Wallis tests were used to determine if TFAP2C H-scores correlate with other tumor markers. Cox proportional hazards regression models were used to determine whether TFAP2C H-scores and other tumor markers were related to overall and disease-free survival in univariate and multivariable models. TFPAC2 overexpression did not impact overall survival during the first 10 years after diagnosis, but was associated with a shorter survival after 10 years (HR 3.40, 95 % CI 1.58, 7.30; p value = 0.002). This late divergence persisted in ER-positive (HR 2.86, 95 % CI 1.29, 6.36; p value = 0.01) and endocrine therapy-positive subgroups (HR 4.19, 95 % CI 1.72, 10.23; p value = 0.002). For the ER+ and endocrine therapy subgroup, the HR was 3.82 (95 % CI 1.53, 9.50; p value = 0.004). TFAP2C H-scores were not correlated with other tumor markers or related to disease-free survival. In this hypothesis-generating study, we show that higher TFAP2C scores correlate with poor overall survival after 10 years of diagnosis in ERα-positive and endocrine therapy-treated subgroups.