Degradation products of extracellular matrix affect cell migration and proliferation.

Biologic scaffolds composed of extracellular matrix (ECM) are utilized in numerous regenerative medicine applications to facilitate the constructive remodeling of tissues and organs. The mechanisms by which the host remodeling response occurs are not fully understood, but recent studies suggest that both constituent growth factors and biologically active degradation products derived from ECM play important roles. The objective of the present study was to determine if degradation of ECM scaffold materials in vitro by methods that are biochemically and physiologically relevant can yield products that possess chemotactic and/or mitogenic activities for fully differentiated mammalian endothelial cells and undifferentiated multipotential progenitor cells.

The androgen metabolite 5alpha-androstane-3beta,17beta-diol (3betaAdiol) induces breast cancer growth via estrogen receptor: implications for aromatase inhibitor resistance.

The aromatase inhibitors (AIs) are used to treat estrogen receptor-positive (ER+) breast tumors in post-menopausal women, and function by blocking the conversion of adrenal androgens to estrogens by the enzyme CYP19 aromatase. Breast cancer patients receiving AI therapy have circulating estrogen levels below the level of detection; however, androgen concentrations remain unchanged. We were interested in studying the effects of androgens on breast cancer cell proliferation under profound estrogen-deprived conditions.

A transcriptional fingerprint of estrogen in human breast cancer predicts patient survival.

Estrogen signaling plays an essential role in breast cancer progression, and estrogen receptor (ER) status has long been a marker of hormone responsiveness. However, ER status alone has been an incomplete predictor of endocrine therapy, as some ER+ tumors, nevertheless, have poor prognosis. Here we sought to use expression profiling of ER+ breast cancer cells to screen for a robust estrogen-regulated gene signature that may serve as a better indicator of cancer outcome.

Genes regulated by estrogen in breast tumor cells in vitro are similarly regulated in vivo in tumor xenografts and human breast tumors.

Background: Estrogen plays a central role in breast cancer pathogenesis. Although many studies have characterized the estrogen regulation of genes using in vitro cell culture models by global mRNA expression profiling, it is not clear whether these genes are similarly regulated in vivo or how they might be coordinately expressed in primary human tumors.

Results: We generated DNA microarray-based gene expression profiles from three estrogen receptor alpha (ERalpha)-positive breast cancer cell lines stimulated by 17beta-estradiol (E2) in vitro over a time course, as well as from MCF-7 cells grown as xenografts in ovariectomized athymic nude mice with E2 supplementation and after its withdrawal.

GREB1 is a novel androgen-regulated gene required for prostate cancer growth.

Background: Gene regulated in breast cancer 1 (GREB1) is a novel estrogen-regulated gene shown to play a pivotal role in hormone-stimulated breast cancer growth. GREB1 is expressed in the prostate and its putative promoter contains potential androgen receptor (AR) response elements.

Methods: We investigated the effects of androgens on GREB1 expression and its role in androgen-dependent prostate cancer growth.

GREB 1 is a critical regulator of hormone dependent breast cancer growth.

Background: Estrogen plays a central role in breast cancer pathogenesis and many potent risk factors for the development of the disease can be explained in terms of increased lifetime exposure to estrogen. Although estrogen regulated genes have been identified, those critically involved in growth regulation remain elusive.METHODS.

Genotyping for polymorphic drug metabolizing enzymes from paraffin-embedded and immunohistochemically stained tumor samples.

Objectives: Paraffin-embedded tumor samples are valuable in the study of cancer for routine staging, tumor marker analysis, and in retrospective studies to test new prognostic and predictive biomarkers. Their utility in retrospective pharmacogenetic analysis of clinical trials has yet to be evaluated. We set out to establish genotyping methods for relevant genes from archival tumor samples and determine if fixation, processing or somatic changes in the tumor might affect our ability to identify germ-line polymorphisms.