Marcin Iwanicki

Ph.D.

Stevens Institute of Technology

Assistant Professor

PLCO (Learn more about this study)

PLCO-1301

Sep 7, 2023

Epigenomic and functional effects of PFOA/PFOS exposures on ovarian cancer (OC) risk loci

Summary: NCI-directed epidemiological studies have started to link PFOA and PFOS exposures to cancer (PMID: 35905598), and evidence suggests that subjecting human epithelial cells to high concentrations of PFOA/PFOS can evoke cancer-risk events including inflammation (PMID: 37239886), and epigenetic changes (PMID: 33751946). However, whether physiological concentrations of PFOA/PFOS evoke inflammation and thereby impact epigenetic patterning specifically at ovarian cancer (OC) risk loci is not yet known, nor it has been explored if remediation of these chemicals could prevent such perturbations, specifically in OC precursors, including fallopian tube non-ciliated epithelial (FNE) cells (PMID: 29061967). This situation motivates us to study whether and how PFOA/PFOS exposures impact cancer risk loci, as defined by public genome-wide association study (GWAS) data, in the genomes of cancer precursor cells. We hypothesize that exposures to PFOA and/or PFOS cause inflammation via activation of canonical signaling pathways (e.g., AIM2/NF-kB, cGAS-STING, NLRP3, STAT3) leading to activation of specific downstream transcription factors (TFs) that reshape the epigenome at OC-risk loci. Our research team, led by Project PI’s with expertise in genetic-epigenetic interactions at disease risk loci (Tycko), and TF signaling and OC initiation from precursor cells (Iwanicki), has three specific aims:

Aim 1. Determine whether inflammation is the key mediator of PFOA/PFOS epigenetic effects on OC risk loci, and whether our findings of epigenetic changes in HOXD1/D3 generalize to other OC risk loci. We will study six independent FNE cell lines exposed to medium containing a range of concentrations of PFOA/PFOS, versus remediated (PFOA/PFOS-depleted) medium, with and without the addition of neutralizing anti-cytokine antibodies. In parallel, we will utilize exposures with combinations of TNF-alpha and a series of other cytokines. Key molecular readouts will be high throughput methyl-seq targeted to OC risk loci, and RNA-seq.

Aim 2. Test specific polymorphic TF binding motifs as the underlying mechanism of ASM at OC-risk loci at baseline, and the responses of these loci to PFOS/PFOA exposures. We will use CRISPR-CAS9 to edit TF binding sites in HOXD1/D3 and other OC-risk loci and use the resulting panels of isogenic cell lines to determine if these sites are critical for the epigenetic changes at these loci induced by PFOS/PFOA exposures.

Aim 3. Identify OC-risk loci-related TFs and determine their role in mediating epigenetic changes downstream of PFOA/PFOS. We will deploy a combination of RNA-seq, motif finding algorithms, CHIP-seq, and shRNA to identify and determine the function of TFs that interact with- and regulate HOXD1/D3 and additional OC risk genes, downstream of PFOA/PFOS exposures.

This project is a collaboration, focused of P42 application, between Georgetown University, Stevens Institute of Technology and Center for Discovery and Innovation , Hackensack Medical Center.

Georgetown University. Sivanesan Dakshanamurthy <Sivanesan.Dakshanamurthy@georgetown.edu>
Stevens Institute of Technology. Marcin Iwanicki <miwanick@stevens.edu>
Center for Discovery and Innovation , Hackensack Medical Center. Benjamin Tycko <benjamintycko@gmail.com>