p300 Knockout Promotes Butyrate Resistance.

Area of Science:

• Oncology
• Molecular Biology
• Gastroenterology

Background:

• Dietary fiber intake is associated with reduced colorectal cancer (CRC) risk, primarily attributed to its fermentation product, butyrate.
• Butyrate exerts anti-cancer effects by inhibiting CRC cell proliferation and inducing apoptosis, often through Wnt signaling pathways.
• However, resistance to butyrate's effects can contribute to CRC development, even with high fiber consumption.

Purpose of the Study:

• To investigate the role of p300, a histone acetylase, in mediating butyrate sensitivity in colorectal cancer cells.
• To determine if p300 deficiency confers resistance to butyrate's anti-cancer effects.
• To explore the potential of restoring p300 expression to re-sensitize CRC cells to butyrate.

Main Methods:

• Generation and analysis of p300 knockout (KO) CRC cells.
• Assessment of butyrate sensitivity in p300 KO CRC cells.
• Re-introduction of p300 expression into p300 KO CRC cells to evaluate restoration of butyrate sensitivity.
• Microarray analysis of gene expression changes associated with butyrate sensitivity.

Main Results:

• p300 knockout CRC cells demonstrated significant resistance to butyrate-induced growth inhibition and apoptosis.
• Restoration of p300 expression in p300 KO CRC cells successfully re-sensitized them to butyrate.
• Gene expression profiling revealed distinct molecular signatures associated with butyrate sensitivity and resistance.

Conclusions:

• p300 expression is essential for mediating the anti-cancer effects of butyrate in colorectal cancer.
• Loss of p300 function contributes to butyrate resistance in CRC.
• Targeting p300 may represent a therapeutic strategy to overcome butyrate resistance in CRC treatment.