# Metabolic flux analysis and PDX models to understand therapeutic vulnerabilities following inhibition of Ref-1 redox signaling in pancreatic cancer

> **NIH NIH R01** · INDIANA UNIVERSITY INDIANAPOLIS · 2024 · $27,108

## Abstract

ABSTRACT
Pancreatic ductal adenocarcinoma (PDAC) exhibits an extraordinary resistance to therapy and often manifests
as metastatic disease. It is characterized by hypoxia, a dense stroma, and metabolic alterations, necessitating
innovative strategies for intervention. Our proposed investigation centers on two main fronts: targeting a redox
signaling protein and developing drug combinations that hold the potential to selectively eliminate the tumor by
disrupting essential survival pathways. This redox factor-1 (Ref-1) is a regulator of critical transcription factors
that fuel pancreatic cancer cell proliferation and resistance to drugs, as well as genes integral to cellular
metabolism. In hypoxic environments, the inhibition of Ref-1 markedly disrupts metabolic pathways (such as the
TCA cycle and oxidative phosphorylation), along with genes influenced by hypoxia-inducible factors (HIFs). This
interference effectively retards the growth of pancreatic cancer co-culture spheroids and xenografts. An initial
Ref-1 inhibitor (APX3330) has completed phase I trials, showcasing promising attributes: a 32% response rate,
favorable pharmacokinetics, substantial target engagement, and minimal toxicity. Encouraged by these results
and guided by a robust structural-activity relationship (SAR) exploration, we have identified next-generation Ref-
1 inhibitors currently in the lead optimization phase. Additionally, we have devised a strategy for patient selection
based on Ref-1 sensitivity and identified molecular partners likely to synergize with Ref-1 inhibition.
Acknowledging the eventual emergence of resistance mechanisms with targeted therapies, our research
endeavors also encompass the formulation of innovative combination strategies. Our overarching hypothesis
posits that by focusing on the redox function of Ref-1, both as a standalone therapy and in conjunction with
meticulously designed combination approaches, we can induce metabolic vulnerability and effectively curtail
pancreatic cancer growth and metastasis.

## Key facts

- **NIH application ID:** 10947465
- **Project number:** 3R01CA282478-01S1
- **Recipient organization:** INDIANA UNIVERSITY INDIANAPOLIS
- **Principal Investigator:** Melissa L. Fishel
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $27,108
- **Award type:** 3
- **Project period:** 2024-05-01 → 2026-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10947465

## Citation

> US National Institutes of Health, RePORTER application 10947465, Metabolic flux analysis and PDX models to understand therapeutic vulnerabilities following inhibition of Ref-1 redox signaling in pancreatic cancer (3R01CA282478-01S1). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10947465. Licensed CC0.

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