Serine synthesis influences tamoxifen response in ER+ human breast carcinoma.

Estrogen receptor-positive breast cancer (ER+ BC) is the most common form of breast carcinoma accounting for approximately 70% of all diagnoses. Although ER-targeted therapies have improved survival outcomes for this BC subtype, a significant proportion of patients will ultimately develop resistance to these clinical interventions, resulting in disease recurrence. Phosphoserine aminotransferase 1 (PSAT1), an enzyme within the serine synthetic pathway (SSP), has been previously implicated in endocrine resistance.

Relationships of protein biomarkers of the urokinase plasminogen activator system with expression of their cognate genes in primary breast carcinomas.

Background: uPA, its receptor uPAR, and inhibitors PAI-1 and PAI-2 play key roles in membrane remodeling/invasion and in predicting response to chemotherapy. We identified novel relationships of these biomarkers with ER/PR that indicate clinical utility for assessing breast carcinoma outcomes.

Methods: Retrospective studies were performed with de-identified results of (a) uPA, uPAR, and PAI-1; (b) estrogen (ER) and progestin receptor (PR); and (c) clinical outcomes.

Expression of Genes for Methylxanthine Pathway-Associated Enzymes Accompanied by Sex Steroid Receptor Status Impacts Breast Carcinoma Progression.

Consumption of methylxanthine alkaloids appears to induce activities by antagonizing adenosine receptors, implicated in breast cancer behavior in vitro. Our goal was to evaluate expression of genes for methylxanthine receptors and metabolizing enzymes to assess risk of breast carcinoma recurrence. Clinical outcomes, estrogen/progestin receptor results, and gene expression assays guided selection.

Clinical outcomes linked to expression of gene subsets for protein hormones and their cognate receptors from LCM-procured breast carcinoma cells.

Purpose: Certain peptide hormones and/or their cognate receptors influencing normal cellular pathways also have been detected in breast cancers. The hypothesis is that gene subsets of these regulatory molecules predict risk of breast carcinoma recurrence in patients with primary disease.

Methods: Gene expression levels of 61 hormones and 81 receptors were determined by microarray with LCM-procured carcinoma cells of 247 de-identified biopsies.

Interaction between smoking history and gene expression levels impacts survival of breast cancer patients.

In contrast to studies focused on cigarette smoking and risk of breast cancer occurrence, this study explored the influence of smoking on breast cancer recurrence and progression. The goal was to evaluate the interaction between smoking history and gene expression levels on recurrence and overall survival of breast cancer patients. Multivariable Cox proportional hazards models were fitted for 48 cigarette smokers, 50 non-smokers, and the total population separately to determine which gene expressions and gene expression/cigarette usage interaction terms were significant in predicting overall and disease-free survival in breast cancer patients.

Temporal Expression of miRNAs in Laser Capture Microdissected Palate Medial Edge Epithelium from Tgfβ3(-/-) Mouse Fetuses.

Clefting of the secondary palate is the most common birth defect in humans. Midline fusion of the bilateral palatal processes is thought to involve apoptosis, epithelial to mesenchymal transition, and cell migration of the medial edge epithelium (MEE), the specialized cells of the palate that mediate fusion of the palatal processes during fetal development. Data presented in this manuscript are the result of analyses designed to identify microRNAs that are expressed and regulated by TGFβ3 in developing palatal MEE.

Gender-associated expression of tumor markers and a small gene set in breast carcinoma.

Breast carcinomas in both genders share pathological features, although differences in incidence, prognosis and survival are reported. Expression of 33 genes was investigated in male and female breast carcinomas in association with ER, PR, HER-2/neu and EGF-receptor. Among 98 male breast cancers, 82 were ER+ and 78 were PR+.

Epigenetic analysis of laser capture microdissected fetal epithelia.

Laser capture microdissection (LCM) is a superior method for nondestructive collection of specific cell populations from tissue sections. Although DNA, RNA, and protein have been analyzed from LCM-procured samples, epigenetic analyses, particularly of fetal, highly hydrated tissue, have not been attempted. A standardized protocol with quality assurance measures was established to procure cells by LCM of the medial edge epithelia (MEE) of the fetal palatal processes for isolation of intact microRNA for expression analyses and genomic DNA (gDNA) for CpG methylation analyses.

Characterization of estrogen response element binding proteins as biomarkers of breast cancer behavior.

Background: While investigating estrogen response element (ERE) binding properties of human estrogen receptor-α (hERα) in breast cancer cytosols, other ERE-binding proteins (ERE-BP) were observed.

Design And Methods: Recognition properties of ERE-BP were evaluated by electrophoretic mobility shift assays (EMSA) with ERE sequences of the 5'-flanking region of the estrogen responsive gene vitellogenin A2 (VitA2). Cytosols were incubated 16 h, 4 °C with [32P]ERE sequences and separated by EMSA.

Interrogating differences in expression of targeted gene sets to predict breast cancer outcome.

Background: Genomics provides opportunities to develop precise tests for diagnostics, therapy selection and monitoring. From analyses of our studies and those of published results, 32 candidate genes were identified, whose expression appears related to clinical outcome of breast cancer. Expression of these genes was validated by qPCR and correlated with clinical follow-up to identify a gene subset for development of a prognostic test.

Protein tyrosine phosphatase 4A2 expression predicts overall and disease-free survival of human breast cancer and is associated with estrogen and progestin receptor status.

Expression of protein tyrosine phosphatase PTP4A2 (also known as PRL2) has been examined in a variety of human carcinomas, although its role in breast cancer remains inconclusive. Since the majority of previous breast cancer studies utilized tissue biopsies composed of heterogeneous cell populations, we hypothesized that an examination of PTP4A2 expression in carcinoma cells isolated by laser capture microdissection (LCM) would provide a more accurate means of assessing its predictive value. From investigations of 247 human breast cancer biopsies collected under standardized, stringent conditions, total RNA was extracted from LCM-procured carcinoma cells to perform microarray analyses to identify gene signatures associated with breast cancer behavior.

Assessment of phytoestrogen and mycoestrogen recognition by recombinant human estrogen receptor-α using ligand titration arrays.

Introduction: Exposure to phytoestrogens and mycoestrogens has emerged as a public health issue due to their potentially endocrine disruption activities resulting from direct interaction with sex-steroid hormone receptors. There is a significant requirement for comprehensive, reproducible methods to determine the extent of estrogen mimicry by compounds encountered in the environment to estimate risk:benefit ratios, particularly in humans.

Objective: To develop a systematic approach for assessing recognition of chemically diverse compounds by human estrogen receptor proteins to aid in their assessment as endocrine disruptor compounds (EDCs).

Co-expression of genes with estrogen receptor-α and progesterone receptor in human breast carcinoma tissue.

Unlabelled: Abstract Background: To detect genes associated with the expression of ESR1 and PGR - as well as of their protein products, estrogen receptor (ER) and progesterone receptor (PR) - 221 de-identified invasive ductal carcinomas of the breast were investigated. Our long-term goal is to decipher relationships between the expression of ER- and PR-associated genes and breast cancer behavior to improve diagnostics and identify new molecular targets for drug design.

Materials And Methods: Frozen tissue sections were evaluated for structural integrity and pathology after hematoxylin and eosin staining.

Expression of urokinase-type plasminogen activator (uPA), its receptor (uPAR), and inhibitor (PAI-1) in human breast carcinomas and their clinical relevance.

Serine proteases convert plasminogen to plasmin which is involved in tissue remodeling under physiologic and pathophysiologic conditions, including breast carcinoma invasion and progression. Both urokinase-type plasminogen activator (uPA) and pro-uPA associate with uPA receptor (uPAR) on target cells, where plasminogen activator inhibitors (e.g.

Relationships of ESR1 and XBP1 expression in human breast carcinoma and stromal cells isolated by laser capture microdissection compared to intact breast cancer tissue.

Results from investigations of human genomics which utilize intact tissue biopsy specimens maybe compromised due to a host of uncontrolled variables including cellular heterogeneity of a sample collected under diverse conditions, then processed and stored using different protocols. To determine the cellular origin and assess relationships of mRNA expression of two genes reported to be co-expressed in human breast carcinoma (estrogen receptor-α, ESR1 and X-box binding protein 1, XBP1), gene expression analyses were performed with intact tissue sections and compared with those of laser capture microdissection (LCM)-procured carcinoma and stromal cells from serial sections of the same tissue. Frozen sections of human breast carcinomas were first evaluated for structural integrity and pathology after hematoxylin and eosin (H&E) staining.

A five-gene model predicts clinical outcome in ER+/PR+, early-stage breast cancers treated with adjuvant tamoxifen.

Primary breast carcinomas expressing both estrogen and progesterone receptors are most likely to respond to tamoxifen therapy, especially in patients with early-stage lesions. However, certain patients exhibit clinicopathologic features suggesting good prognosis relapse within 10 years, justifying a search for biomarkers identifying patients at risk for recurrence. Nine candidate genes associated with estrogen signaling were selected from microarray studies and combined with those for conventional biomarkers (ESR1, PGR, ERBB2).

American Society of Clinical Oncology/College of American Pathologists guideline recommendations for immunohistochemical testing of estrogen and progesterone receptors in breast cancer (unabridged version).

Purpose: To develop a guideline to improve the accuracy of immunohistochemical (IHC) estrogen receptor (ER) and progesterone receptor (PgR) testing in breast cancer and the utility of these receptors as predictive markers.

Methods: The American Society of Clinical Oncology and the College of American Pathologists convened an international Expert Panel that conducted a systematic review and evaluation of the literature in partnership with Cancer Care Ontario and developed recommendations for optimal IHC ER/PgR testing performance.

Results: Up to 20% of current IHC determinations of ER and PgR testing worldwide may be inaccurate (false negative or false positive).

Angiogenesis-associated sequence variants relative to breast cancer recurrence and survival.

Introduction: Breast cancer (BrCA) risk stratification using clinico-pathological biomarkers helps improve disease prognosis prediction. However, disease recurrence rates remain unfavorable and individualized clinical management strategies are needed. Consequently, we evaluated the influence of 14 sequence variants detected in IL-10, TGF-β1, VEGF, and their associated receptors as effective predictors of BrCA clinical outcomes.

American Society of Clinical Oncology/College of American Pathologists guideline recommendations for immunohistochemical testing of estrogen and progesterone receptors in breast cancer.

Purpose: To develop a guideline to improve the accuracy of immunohistochemical (IHC) estrogen receptor (ER) and progesterone receptor (PgR) testing in breast cancer and the utility of these receptors as predictive markers.

Methods: The American Society of Clinical Oncology and the College of American Pathologists convened an international Expert Panel that conducted a systematic review and evaluation of the literature in partnership with Cancer Care Ontario and developed recommendations for optimal IHC ER/PgR testing performance.

Results: Up to 20% of current IHC determinations of ER and PgR testing worldwide may be inaccurate (false negative or false positive).

American Society of Clinical Oncology/College Of American Pathologists guideline recommendations for immunohistochemical testing of estrogen and progesterone receptors in breast cancer.

Purpose: To develop a guideline to improve the accuracy of immunohistochemical (IHC) estrogen receptor (ER) and progesterone receptor (PgR) testing in breast cancer and the utility of these receptors as predictive markers.

Methods: The American Society of Clinical Oncology and the College of American Pathologists convened an international Expert Panel that conducted a systematic review and evaluation of the literature in partnership with Cancer Care Ontario and developed recommendations for optimal IHC ER/PgR testing performance.

Results: Up to 20% of current IHC determinations of ER and PgR testing worldwide may be inaccurate (false negative or false positive).

Steroid receptor and growth factor receptor expression in human nonsmall cell lung cancers using cells procured by laser-capture microdissection.

Few biomarkers exist for management of nonsmall cell lung cancers (NSCLC), although estrogen receptor (ERalpha and ERbeta) and EGF receptor (EGFR) expression has been related to clinical outcome. To circumvent problems of cellular heterogeneity in whole tissue, relative gene expression of ERalpha, ERbeta, EGFR, and HER-2 (c-erb-B2) was examined in pure lung carcinoma (LC) cells and normal epithelia by LCM. Cell-specific RNA was isolated and purified for RT-qPCR and microarray.

Molecular signatures of estrogen receptor-associated genes in breast cancer predict clinical outcome.

Our goal is to identify new molecular targets for drug design and improve understanding of the molecular basis of clinical behavior and therapeutic response of breast cancer (BC). Pure populations of BC cells were procured by laser capture microdissection (LCM) from deidentified tissue specimens. RNA from either LCM-procured cells or whole tissue sections was extracted, purified, and quantified by RT-qPCR using beta-actin for relative quantification.

Biosensors for detecting estrogen-like molecules and protein biomarkers.

A novel evanescent-based biosensor (Endotect, ThreeFold Sensors, Inc.) was developed with laser-based fiber optics using fluorescent dye-labeled recombinant human estrogen receptor-alpha (rhERalpha) and hERbeta as probes. A three-tiered approach evaluating various steps in the formation of the estrogen-receptor complex and its subsequent activity was developed for instrument calibration to detect estrogen mimics in biological samples, water and soil.

A three-tiered approach for calibration of a biosensor to detect estrogen mimics.

A three-tiered approach was developed to determine the influence of a chemically-diverse group of compounds exhibiting estrogen mimicry using recombinant human estrogen receptor (rhER) activity to calibrate a receptor protein-based biosensor. In the initial tier, a ligand competition array was developed to evaluate compounds inhibiting [3H]estradiol-17beta binding to rhER. Each of six different concentrations of [3H]estradiol-17beta was mixed with increasing concentrations of an unlabeled putative mimic.