Crosstalk between CXCR4/ACKR3 and EGFR Signaling in Breast Cancer Cells

Area of Science:

• Oncology
• Molecular Cell Biology
• Cancer Signaling

Background:

• Improved breast cancer (BC) therapies necessitate a deeper understanding of receptor and signaling pathway crosstalk.
• The interplay between chemokine receptors (CXCL12/CXCR4/ACKR3) and epidermal growth factor receptor (EGFR) family signaling in BC progression remains incompletely understood.

Purpose of the Study:

• To investigate the crosstalk between CXCL12/CXCR4/ACKR3 and EGFR signaling cascades in diverse breast cancer subtypes.
• To elucidate the molecular mechanisms underlying this interaction and its role in promoting cancer progression.

Main Methods:

• Utilized cell models representing major breast cancer subtypes (luminal B, luminal A, triple-negative).
• Analyzed expression profiles of CXCR4 and ACKR3 chemokine receptors.
• Investigated signaling pathway activation, particularly ERK1/2, in response to CXCL12 and crosstalk with EGFR signaling.

Main Results:

• Breast cancer cell lines exhibited heterogeneous CXCR4/ACKR3 expression, with varied localization and cell surface proportions.
• In MDA-MB-361 (luminal B, Her2+) cells, CXCR4/ACKR3 and EGFR signaling components converged to promote ERK1/2 activation.
• This crosstalk involved the G protein-coupled receptor kinase 2 (GRK2) and Src tyrosine kinase.

Conclusions:

• A significant cooperation exists between CXCR4/ACKR3 and EGFR signaling in specific breast cancer subtypes.
• This interplay integrates signals from the tumor microenvironment, contributing to cancer progression.
• Targeting these crosstalk mechanisms may offer novel therapeutic strategies for certain breast cancers.