Systematic identification of cancer cell vulnerabilities to natural killer cell-mediated immune surveillance

Area of Science:

• Immunology
• Oncology
• Molecular Biology

Background:

• Limited efficacy of T-cell checkpoint inhibitors necessitates alternative immunotherapeutics.
• Natural killer (NK) cell effector functions are crucial for anti-cancer immunity.
• Understanding the tumor-immune synapse is key to enhancing immunotherapy response.

Purpose of the Study:

• To identify genetic perturbations enhancing NK cell activity in leukemia using CRISPR-Cas9 screening.
• To investigate the role of DCAF15 in regulating cancer cell sensitivity to NK-mediated killing.
• To explore the therapeutic potential of DCAF15 inhibition in myeloid neoplasms.

Main Methods:

• CRISPR-Cas9 genetic screens in a leukemia cell line.
• Analysis of tumor-immune synapse components and interferon-γ signaling.
• Proteomic and biochemical characterization of DCAF15 substrates.
• Evaluation of indisulam, a DCAF15-targeting drug.
• Correlation of DCAF15 expression with patient survival in Acute Myeloid Leukemia (AML).

Main Results:

• Disruption of DCAF15 sensitized leukemia cells to NK-mediated clearance.
• DCAF15 inhibition induced an inflamed phenotype in cancer cells, upregulating costimulatory molecules.
• Cohesin complex proteins were identified as DCAF15 client substrates.
• The anticancer drug indisulam mimicked the effects of DCAF15 genetic disruption.
• Reduced DCAF15 expression in AML patients correlated with improved survival.

Conclusions:

• DCAF15 plays a critical role in regulating cancer cell immunogenicity and NK cell recognition.
• Inhibition of DCAF15 represents a promising strategy for enhancing NK cell-based immunotherapies.
• Targeting DCAF15 with drugs like indisulam may offer a new therapeutic avenue for myeloid neoplasms.