PGC-1α Controls Mitochondrial Biogenesis in Drug-Resistant Colorectal Cancer Cells by Regulating Endoplasmic...

Area of Science:

• Oncology
• Molecular Biology
• Biochemistry

Background:

• Colorectal cancer (CRC) drug resistance poses a significant clinical challenge.
• Existing strategies to overcome chemoresistance in CRC are limited.
• Understanding the molecular mechanisms of drug resistance is crucial for developing novel therapies.

Purpose of the Study:

• To investigate the role of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) in 5-fluorouracil (5FU)-resistant CRC cells.
• To characterize the functional changes in 5FU-resistant CRC cells, focusing on mitochondrial activity and PGC-1α expression.
• To explore PGC-1α as a potential therapeutic target for overcoming 5FU resistance in CRC.

Main Methods:

• Characterization of 5FU-resistant CRC cell lines.
• Assessment of mitochondrial biogenesis and activity (complex I and IV).
• Measurement of antioxidant enzyme activity, oxygen consumption, and cell survival.
• Analysis of PGC-1α expression levels.
• Evaluation of endoplasmic reticulum (ER) stress and apoptosis induction.

Main Results:

• 5FU-resistant CRC cells exhibited significantly increased PGC-1α expression compared to sensitive cells.
• Elevated PGC-1α promoted mitochondrial biogenesis, oxidative phosphorylation, and antioxidant defenses against 5FU-induced reactive oxygen species.
• PGC-1α suppressed 5FU-induced ER stress and subsequent apoptosis in resistant CRC cells.
• 5FU treatment had limited impact on mitochondrial function and cell survival in resistant cells.

Conclusions:

• PGC-1α plays a critical role in conferring 5FU resistance in colorectal cancer cells.
• Increased PGC-1α expression enhances cellular defense mechanisms, including mitochondrial function and antioxidant capacity.
• Targeting PGC-1α may represent a novel therapeutic strategy to overcome 5FU resistance in CRC patients.