Elevated GRHL2 imparts plasticity in estrogen receptor positive breast cancer cells [ChIP-Seq]

Estrogen receptor (ER) positive breast cancer is characterized by a late recurrence following initial treatment. The epithelial cell fate transcription factor Grainyhead-like protein 2 (GRHL2) is amplified in ER positive breast cancers and is indicative of poorer prognosis as compared to ER negative breast cancer. To understand how GRHL2 contributes to progression, GRHL2 was overexpressed in ER positive cells. To determine how GRHL2 overexpression affects GRHL2 binding to DNA, ChIP sequencing was conducted to evaluate binding intensity and location. To investigate the long-term effects of elevated GRHL2, a tetracycline-inducible cell line capable of expressing GRHL2-GFP upon exposure to doxycycline hyclate (Dox) was treated with 1 μg/mL for 24, 48, or 72 hours, with media changes every 24 hours. Cells were fixed, sonicated, and immunoprecipitated with an anti-GRHL2 antibody prior to library preparation. All samples included were analyzed with 3 biological replicates. ChIP sequencing was performed by AZENTA Life Sciences Next Generation Sequencing. Differential gene expression and motif analyses were conducted using ChIP-seq data.