# NR3C1, LAX1, and RCAN3 as Circulating Epigenetic Biomarkers for Prognosis and Chemotherapy Response Prediction in Metastatic Pancreatic Cancer

## TL;DR

This study identifies three genes (LAX1, NR3C1, and RCAN3) with altered methylation in blood DNA as potential non-invasive biomarkers for predicting prognosis and chemotherapy response in metastatic pancreatic cancer.

## Contribution

The study introduces cfDNA methylation of LAX1, NR3C1, and RCAN3 as novel prognostic and predictive biomarkers for mPDAC.

## Key findings

- Altered methylation of LAX1, NR3C1, and RCAN3 in cfDNA was associated with poor prognosis in metastatic pancreatic cancer patients.
- Baseline NR3C1 methylation predicted chemotherapy response with 75% sensitivity and 92.86% specificity.
- Methylation levels of these genes correlated with other biomarkers like CA19-9 and cfDNA fragmentation.

## Abstract

Pancreatic cancer remains highly lethal, largely due to late diagnosis and limited efficacy of treatments. Improving first‐line treatment selection and patient monitoring requires novel, non‐invasive biomarkers beyond carbohydrate antigen 19‐9 (CA19‐9) and imaging. This study investigates epigenetic biomarkers from liquid biopsy with prognostic and predictive potential in metastatic pancreatic ductal adenocarcinoma (PDAC; mPDAC). Genome‐wide methylation profiling of cell‐free DNA (cfDNA) from healthy individuals and stage IV mPDAC patients identified 13 gene‐associated CpG sites with significantly altered methylation patterns. ddPCR validation confirmed consistent methylation differences in lymphocyte transmembrane adaptor 1 (LAX1), nuclear receptor subfamily 3 group C member 1 (NR3C1), and RCAN3 between healthy and patient groups. Elevated LAX1 and RCAN3 methylation and reduced NR3C1 methylation at diagnosis were associated with poor prognosis and correlated with high‐risk circulating biomarker profiles, including CA19‐9 levels, RAS MAF (mutant allele fraction), cfDNA concentration, and cfDNA fragmentation. Notably, baseline NR3C1 methylation levels predicted response to first‐line FOLFIRINOX‐based treatment with an acceptable 75% sensitivity and a high specificity of 92.86%. These findings highlight the clinical significance of cfDNA methylation as a minimally invasive biomarker source, emphasizing LAX1, NR3C1, and RCAN3 as prognostic biomarkers in mPDAC. Specifically, baseline NR3C1 methylation emerges as a promising predictor of treatment response, supporting personalized therapeutic strategies in mPDAC.

Clinical utility of liquid biopsy‐based epigenetic profiling in PDAC management. Aberrant methylation of LAX1, RCAN3, and NR3C1 was identified in cfDNA from mPDAC patients, highlighting their potential as non‐invasive epigenetic biomarkers. Methylation levels of these genes showed prognostic value, supporting their relevance for patient stratification and disease monitoring. Notably, NR3C1 methylation emerged as a predictive biomarker of first‐line treatment response, with high circulating levels—potentially reflecting low tumor expression—associated with improved outcomes under FOLFIRINOX‐based therapies. Some elements of this figure were sourced from Servier Medical Art (https://smart.servier.com/).