Preferred Label : MTA3 Pathway;
NCIt related terms : Downregulated of MTA-3 in ER-negative Breast Tumors;
Alternative definition : BIOCARTA: Approximately 30% of breast carcinomas lack ER expression. Presumably, these
breast cancers become estrogen independent through genetic alterations that bypass
the requirement for ER-dependent stimulation of cell proliferation. As such, estrogen
receptor is a key regulator of proliferation and differentiation in mammary epithelia
and represents a crucial prognostic indicator and therapeutic target in breast cancer.
Mechanistically, estrogen receptor induces changes in gene expression through direct
gene activation of a number of genes (e.g., cathepsin D, HSP27, alpha-tubulin, glyceraldehyde-3-phosphatase,
Pdzk1, Greb) and also through the biological functions of target loci. The product
of human MTA3 has been identified as an estrogen-dependent component of the Mi-2/NuRD
transcriptional corepressor in breast epithelial cells and demonstrates that MTA3
constitutes a key component of an estrogen-dependent pathway regulating growth and
differentiation. The absence of estrogen receptor or of MTA3 leads to aberrant expression
of the transcriptional repressor Snail, a master regulator of epithelial to mesenchymal
transitions. Aberrant Snail expression results in loss of expression of the cell adhesion
molecule E-cadherin, an event associated with changes in epithelial architecture and
invasive growth. MTA3 is the mechanistic link between estrogen receptor status and
invasive growth of breast cancers. (This definition may be outdated - see the DesignNote.);
NCIt note : The BIOCARTA Definition (ALT_DEFINITION) for this pathway concept was provided by
BioCarta. This property was not created by, nor is it maintained by the NCI Thesaurus
staff. Additionally, BioCarta is no longer updating its pathway data; thus, the BIOCARTA
Definition might be outdated or inaccurate. Please see the Terms and Conditions for
Use at http://www.biocarta.com/.;
Biocarta ID : h_mta3Pathway;
Origin ID : C39158;
UMLS CUI : C1518143;
Semantic type(s)
has_gene_product_element
pathway_has_gene_element