Cleaved Caspase-3 Transcriptionally Regulates Angiogenesis-Promoting Chemotherapy Resistance

Area of Science:

• Molecular Biology
• Cancer Research
• Cell Biology

Background:

• Caspases are primarily known for their role in apoptosis.
• Noncanonical, nonapoptotic functions of caspases are emerging but poorly understood.
• The specific mechanisms of caspase-3's nonapoptotic roles require further elucidation.

Purpose of the Study:

• To investigate the nonapoptotic functions of cleaved caspase-3.
• To identify the mechanisms by which caspase-3 influences cancer progression.
• To explore cleaved caspase-3 as a potential therapeutic target in cancer.

Main Methods:

• Utilized human and mouse caspase-3 proficient and deficient cancer cell lines.
• Assessed DNA binding capabilities and transcriptional activity of cleaved caspase-3.
• Analyzed gene expression of proangiogenic and apoptotic factors.
• Evaluated the impact of caspase-3 inhibition on chemotherapy efficacy and tumor development.

Main Results:

• Cleaved caspase-3 functions as a DNA-binding transcription factor via its small subunit.
• Caspase-3 DNA binding upregulates proangiogenic genes, enhancing angiogenesis and endothelial cell activation.
• Proapoptotic gene expression was downregulated in caspase-3 proficient cells.
• Inhibition of caspase-3 improved chemotherapy efficacy and reduced spontaneous tumor formation.

Conclusions:

• Cleaved caspase-3 possesses a novel nonapoptotic role as a transcription factor.
• Caspase-3 transcriptionally regulates the VEGFR pathway, promoting angiogenesis.
• Targeting cleaved caspase-3 presents a promising new therapeutic strategy for cancer treatment.