Melanoma-derived IL-1 converts vascular endothelium to a proinflammatory and procoagulatory phenotype via NFκB...

Area of Science:

• Oncology
• Cell Biology
• Immunology

Background:

• Melanoma metastasis involves tumor cell extravasation, facilitated by pro-inflammatory and pro-coagulatory conditions.
• Endothelial cells (ECs) play a crucial role in regulating vascular interactions during tumor progression.

Purpose of the Study:

• To investigate the mechanisms by which human melanoma cell lines activate endothelial cells in vitro.
• To elucidate the pathways involved in melanoma-induced endothelial cell activation and its consequences for tumor progression.

Main Methods:

• In vitro co-culture assays using human melanoma cell lines (MV3, WM9) and endothelial cells (ECs).
• Analysis of endothelial cell responses including calcium flux, von Willebrand factor (vWF) release, and nuclear factor kappa B (NFκB) activation.
• Measurement of cytokine and adhesion molecule expression (IL-6, IL-8, ICAM-1, VCAM-1, Tissue Factor) in ECs.

Main Results:

• MV3 melanoma cells induced rapid, calcium-flux-dependent endothelial activation with ultra-large von Willebrand factor (ULVWF) fiber release.
• WM9 melanoma cell supernatant triggered NFκB activation in ECs, dependent on melanoma-secreted IL-1α and IL-1β.
• Melanoma-derived IL-1 upregulated pro-inflammatory cytokines (IL-6, IL-8), adhesion molecules (ICAM-1, VCAM-1), and Tissue Factor (TF) in ECs.

Conclusions:

• Melanoma cells activate ECs via direct, rapid mechanisms or indirect IL-1/NFκB pathways.
• Both activation pathways transform ECs into a pro-inflammatory and pro-coagulatory surface, promoting melanoma metastasis.