Adaptive metabolic rewiring to chronic SFK inhibition

Area of Science:

• Oncology
• Molecular Biology
• Pharmacology

Background:

• Src family kinases (SFK) regulate critical cellular processes including proliferation, survival, and angiogenesis.
• SFK inhibitors are investigated as anti-metastasis agents for various cancers, including breast cancer.
• Dasatinib is an SFK inhibitor used to study resistance mechanisms in triple-negative breast cancer.

Purpose of the Study:

• To investigate the effects of chronic SFK inhibition on breast cancer cell signaling.
• To identify molecular mechanisms underlying acquired resistance to SFK inhibitors.
• To explore potential combination therapies for overcoming SFK inhibitor resistance.

Main Methods:

• Utilized a triple-negative breast cancer cell line (BT20) and its dasatinib-resistant counterpart.
• Compared cellular responses to dasatinib in parental and resistant cell lines.
• Assessed the impact of various signaling pathway inhibitors on dasatinib resistance.

Main Results:

• Chronic SFK inhibition led to increased dependency on TGFβ signaling for proliferation in BT20 cells.
• Acquired resistance to dasatinib, but not de novo resistance, was diminished by compounds targeting PI3K/mTORC1, ER stress, or autophagy.
• These findings suggest distinct resistance mechanisms depending on the duration of SFK inhibition.

Conclusions:

• Targeting TGFβ signaling may be a viable strategy to counteract resistance to SFK inhibitors in breast cancer.
• Combination therapies involving SFK inhibitors with agents modulating PI3K/mTORC1, ER stress, or autophagy could overcome acquired resistance.
• Understanding resistance mechanisms is crucial for developing effective SFK-targeted cancer therapies.