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Relationship: 3609
Title
Cell differentiation, altered leads to Increase, Hyperplasia (glandular epithelial cells of endometrium)
Upstream event
Downstream event
Key Event Relationship Overview
AOPs Referencing Relationship
Taxonomic Applicability
Sex Applicability
Life Stage Applicability
Key Event Relationship Description
Using a mammary-specific, inducible mouse model of Six1 overexpression, we show that Six1, when misexpressed in the adult mammary epithelium, does indeed induce mammary hyperplasia and aggressive tumor formation. [six1 expands the mouse mammary epithelial stem/progenitor cell pool and induces mammary tumors that undergo epithelial-mesenchymal transition]
Evidence Collection Strategy
This Key Event Relationship was part of an Environmental Protection Agency effort to develop AOPs that establish scientifically supported causal linkages between alternative endpoints measured using new approach methodologies (NAMs) and guideline apical endpoints measured in Tier 1 and Tier 2 test guidelines (U.S. EPA, 2024) employed by the Endocrine Disruptor Screening Program (EDSP). A series of key events that represent significant, measurable, milestones connecting molecular initiation to apical endpoints indicative of adversity were identified based on scientific review articles and empirical studies. Additionally, scientific evidence supporting the causal relationships between each pair of key events was assembled and evaluated. The present effort focused primarily on empirical studies with laboratory rodents and other mammals.