IDH1 Inhibition Potentiates Chemotherapy Efficacy in Pancreatic Cancer

Area of Science:

• Oncology
• Cancer Metabolism
• Drug Discovery

Background:

• Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis with universal chemotherapy resistance.
• Wild-type isocitrate dehydrogenase 1 (IDH1) overexpression in PDAC cells contributes to metabolic stress adaptation and treatment resistance.

Purpose of the Study:

• To investigate the role of wild-type IDH1 in PDAC chemotherapy resistance.
• To evaluate the therapeutic potential of combining IDH1 inhibition with conventional chemotherapy.

Main Methods:

• Assessed IDH1 expression and its role in PDAC cell survival post-chemotherapy.
• Utilized in vitro and in vivo murine models of PDAC to test the combination of IDH1 inhibitor (ivosidenib) and chemotherapeutics.

Main Results:

• Chemotherapy induced reactive oxygen species (ROS) and increased tricarboxylic acid cycle activity, upregulating wild-type IDH1 as a resistance mechanism.
• IDH1 inhibition synergized with chemotherapy in vitro and enhanced efficacy of subtherapeutic doses in vivo.
• IDH1 supports PDAC survival by maintaining mitochondrial function and antioxidant defense.

Conclusions:

• Targeting wild-type IDH1 enhances sensitivity to chemotherapy in PDAC by suppressing mitochondrial function and increasing oxidative stress.
• Combining IDH1 inhibition with chemotherapy represents a promising therapeutic strategy for pancreatic cancer.
• An ongoing clinical trial (NCT05209074) is investigating this combination therapy.