Potent ferroptosis agent RSL3 induces cleavage of Pyroptosis-Specific gasdermins in Cancer cells

Area of Science:

• Biochemistry
• Cell Biology
• Oncology

Background:

• Ferroptosis is an iron-dependent cell death pathway crucial for anti-cancer therapy development.
• Current ferroptosis research relies on inducers/inhibitors with potential off-target effects, limiting pathway clarity.
• Investigating overlapping cell death pathways is essential for understanding complex cancer biology.

Purpose of the Study:

• To determine if the ferroptosis inducer RSL3 initiates pyroptosis in cancer cells.
• To analyze the role of specific inhibitors in modulating RSL3-induced cell death.
• To establish the necessity of pathway-specific biomarkers for mechanism of action studies.

Main Methods:

• Treatment of six cancer cell lines with RSL3 and various inhibitors (ferroptosis, caspase, necroptosis, BID, STING).
• Assessment of pyroptosis and ferroptosis biomarkers using a novel quantitative multiplex immunoassay.
• Quantification of cytokine secretion (IL-1α, IL-1β, IL-18) and gasdermin D/E (GSDMD/E) cleavage.

Main Results:

• RSL3 treatment induced pyroptosis hallmarks in 5 out of 6 cancer cell lines.
• Increased secretion of pyroptosis-associated cytokines and GSDMD/E cleavage were observed.
• Ferrostatin-1, BID, and STING inhibitors blocked RSL3-induced cytotoxicity and GSDMD/E cleavage.

Conclusions:

• The ferroptosis inducer RSL3 effectively triggers pyroptosis in cancer cells.
• BID and STING pathways are implicated in RSL3-mediated pyroptosis induction.
• Accurate biomarker measurement is critical for elucidating cytotoxic agent mechanisms and guiding cancer therapy.