Blocking tumor-intrinsic MNK1 kinase restricts metabolic adaptation and diminishes liver metastasis

Area of Science:

• Oncology
• Molecular Biology
• Cancer Research

Background:

• Dysregulation of the MNK1/2-eIF4E signaling pathway is implicated in breast cancer progression.
• Mitogen-activated protein kinase interacting kinase 1 (MNK1) influences cancer stem cells (CSCs), which drive metastasis, recurrence, and treatment resistance.
• The specific role of MNK1 in regulating CSCs is not well understood.

Purpose of the Study:

• To investigate the function of MNK1 in regulating cancer stem cell properties and tumor progression.
• To elucidate the impact of MNK1 on tumor cell metabolism and metastasis.
• To explore the therapeutic potential of targeting MNK1/2.

Main Methods:

• Generation of MNK1 knockout cancer cell lines.
• In vitro and in vivo assessment of CSC properties and tumor growth.
• Multiomics analysis to determine metabolic changes.
• Analysis of The Cancer Genome Atlas (TCGA) data for correlation studies.

Main Results:

• MNK1 knockout led to diminished CSC properties in vitro and slower tumor growth in vivo.
• Loss of MNK1 restricted tumor cell metabolic adaptation, reducing glycolysis and increasing reliance on oxidative phosphorylation.
• MNK1-null cells showed suppressed metastasis to the liver but not the lung.
• TCGA data analysis confirmed a positive correlation between MNK1 expression and glycolytic enzyme expression in breast cancer patients.

Conclusions:

• MNK1 plays a crucial role in maintaining CSC properties and promoting tumor growth and metastasis.
• Targeting MNK1 induces significant metabolic perturbations, including reduced glycolysis and altered energy metabolism.
• Metabolic reprogramming is a novel consequence of MNK1/2 inhibition, presenting a potential therapeutic strategy for cancer treatment.