Cytoglobin Silencing Promotes Melanoma Malignancy but Sensitizes for Ferroptosis and Pyroptosis Therapy Response

Area of Science:

• Oncology
• Cell Death Mechanisms
• Molecular Biology

Background:

• Melanoma treatment resistance remains a challenge, potentially due to dedifferentiated cancer cells.
• Dedifferentiated melanoma cells exhibit increased sensitivity to ferroptosis, a form of regulated cell death.
• Cytoglobin (CYGB), an iron-binding protein, is downregulated in melanoma and may influence cell state.

Purpose of the Study:

• To investigate the role of Cytoglobin (CYGB) in regulating ferroptosis sensitivity in melanoma cells.
• To explore the impact of CYGB knockdown on melanoma cell malignancy and cell death pathways.

Main Methods:

• Utilized G361 melanoma cells with endogenous CYGB expression.
• Administered (1S, 3R)-RAS-selective lethal small molecule (RSL3) to induce ferroptosis.
• Performed transcriptome analysis to assess pathway enrichment.
• Investigated the activation of the NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome.

Main Results:

• CYGB knockdown in G361 cells increased sensitivity to RSL3-induced ferroptosis.
• Knockdown led to elevated basal reactive oxygen species (ROS) and lipid peroxidation.
• Transcriptome analysis revealed enrichment of cancer malignancy pathways upon CYGB knockdown.
• CYGB silencing activated the NLRP3 inflammasome and induced pyroptosis.

Conclusions:

• Silencing Cytoglobin (CYGB) enhances melanoma cell sensitivity to ferroptosis and pyroptosis.
• CYGB plays a tumor-suppressive role by modulating cell death signaling.
• Targeting CYGB may represent a novel therapeutic approach for overcoming melanoma treatment resistance.