AIM2 Inhibits BRAF-Mutant Colorectal Cancer Growth in a Caspase-1-Dependent Manner

Area of Science:

• Immunology
• Oncology
• Molecular Biology

Background:

• Absent in melanoma 2 (AIM2) is a DNA sensor involved in innate immunity.
• AIM2's role in BRAF-mutant colorectal cancer (CRC) pathogenesis is not well understood.
• Understanding AIM2's function in BRAF-mutant CRC is crucial for developing targeted therapies.

Purpose of the Study:

• To investigate the expression level of AIM2 in BRAF-mutant CRC.
• To elucidate the functional role and underlying mechanisms of AIM2 in BRAF-mutant CRC cell growth and progression.
• To evaluate the therapeutic potential of AIM2 in preclinical models of BRAF-mutant CRC.

Main Methods:

• Analysis of AIM2 expression in BRAF-mutant versus wild-type CRC tumor tissues.
• In vitro studies involving AIM2 overexpression in CRC cells, including cell viability, cell death detection, and caspase activity assays.
• In vivo evaluation of AIM2's antitumor effects using cell-derived tumor xenograft (CDX) models and patient-derived organoids (PDOs).

Main Results:

• AIM2 expression was found to be lower in BRAF-mutant CRC tissues compared to BRAF wild-type tissues.
• Overexpression of AIM2 significantly inhibited BRAF-mutant CRC cell viability and induced necrotic cell death.
• AIM2-mediated cell death was dependent on caspase-1 activation.
• AIM2 overexpression demonstrated significant antitumor and anti-metastatic effects in vivo and in PDO models.

Conclusions:

• AIM2 acts as a tumor suppressor in BRAF-mutant CRC.
• AIM2 inhibits BRAF-mutant colon cancer growth and metastasis via a caspase-1-dependent pathway.
• AIM2 represents a potential therapeutic target for BRAF-mutant CRC.