MCT4 is induced by metastasis-enhancing pathogenic mitochondrial NADH dehydrogenase gene mutations and can be a...

Area of Science:

• Mitochondrial genetics
• Cancer biology
• Molecular oncology

Background:

• Pathogenic mitochondrial NADH dehydrogenase (ND) gene mutations promote cancer cell invasion and metastasis.
• Monocarboxylate transporter 4 (MCT4) is overexpressed in solid tumors, supporting cancer cell proliferation and survival.

Purpose of the Study:

• To investigate the relationship between pathogenic ND mutations and MCT4 expression in non-small cell lung cancer (NSCLC).
• To explore MCT4 as a potential biomarker and therapeutic target in metastatic NSCLC.

Main Methods:

• Analysis of MCT4 expression in mouse transmitochondrial cybrids with ND6 mutations.
• Detection of MCT4 levels in human NSCLC cell lines and tissues.
• Assessment of MCT4 regulation by N-acetyl-L-cysteine and signaling pathways (PI3K/AMPK/mTOR).
• Evaluation of MCT1/4 and MCT1/2 inhibitor efficacy on NSCLC cells.

Main Results:

• MCT4 was exclusively expressed in mouse cybrids harboring metastasis-enhancing pathogenic ND6 mutations.
• High MCT4 levels were found in human NSCLC cells and tissues with predicted pathogenic ND mutations, correlating with poor prognosis.
• N-acetyl-L-cysteine suppressed MCT4 expression, and PI3K/AMPK/mTOR pathways were involved in its regulation.
• An MCT1/4 inhibitor, but not an MCT1/2 inhibitor, effectively killed NSCLC cells with predicted pathogenic ND mutations.

Conclusions:

• Pathogenic ND mutations augment MCT4 expression.
• MCT4 is a potential biomarker for metastatic NSCLC associated with pathogenic ND mutations.
• Targeting MCT4 offers a potential therapeutic strategy for NSCLC patients with pathogenic ND mutations.