Molecular Pathways: Targeting the PI3K Pathway in Cancer-BET Inhibitors to the Rescue

Area of Science:

• Oncology
• Molecular Biology
• Epigenetics

Background:

• The phosphoinositide 3-kinase (PI3K) signaling pathway regulates essential cellular functions like growth and survival.
• Mutations in the PI3K pathway are frequent in many cancers, making it a key therapeutic target.
• Tumor cells develop resistance to PI3K inhibitors through feedback and compensatory signaling mechanisms.

Purpose of the Study:

• To review the PI3K pathway as a cancer therapy target.
• To discuss the potential of bromodomain and extraterminal (BET) inhibitors to enhance PI3K inhibitor efficacy.
• To explore BET inhibition's role in overcoming resistance to PI3K-targeted therapies.

Main Methods:

• Review of existing literature on PI3K pathway signaling in cancer.
• Analysis of studies investigating BET inhibitors in combination with PI3K inhibitors.
• Discussion of molecular mechanisms underlying resistance and resensitization.

Main Results:

• Aberrant PI3K pathway activation drives cancer development and progression.
• BET inhibitors have demonstrated efficacy in blocking adaptive signaling responses to PI3K inhibitors.
• Combinatorial therapy with BET and PI3K inhibitors can restore sensitivity in resistant cancer cells.
• BET inhibitors also impact other oncogenic pathways like MAPK, JAK/STAT, and ER.

Conclusions:

• The PI3K pathway remains a significant target for cancer treatment.
• BET inhibition presents a promising strategy to enhance the clinical effectiveness of PI3K inhibitors.
• Combination therapy holds potential for treating diverse oncogenic signals regulated by homeostatic mechanisms.