The Fas-FADD-caspase-8 axis is a cancer cell-intrinsic determinant of cytotoxic lymphocyte-mediated killing

Authors

Solli, E., Wang, S., Wei, Q., Saidu, N. E. B., Tasken, K., Li, Y.

Abstract

Cytotoxic lymphocytes induce cancer cell death through death receptor-ligand interactions and the perforin-granzyme pathway. These pathways are generally thought to converge on the activation of executioner caspases to drive apoptosis. Here, we employed a reductionist approach to systematically disrupt key cell death mediators in a cytotoxic lymphocyte killing system to define their roles in determining cancer cell fate. We found that loss of executioner caspases conferred only limited resistance to cytotoxic lymphocyte-mediated killing. To identify cancer cell-intrinsic regulators that function beyond executioner caspases, we performed unbiased genome-wide CRISPR screens in executioner caspase-deficient cells. Unexpectedly, disruption of Fas or FADD-core components of the death receptor pathway-conferred substantial resistance to cytotoxic lymphocyte-mediated killing even in the absence of executioner caspases. This resistance persisted following additional disruption of known downstream mediators of Fas-FADD-caspase-8 (CASP8) signaling. Together, these findings identify the Fas-FADD-CASP8 axis as a central cancer cell-intrinsic determinant of susceptibility to cytotoxic lymphocyte-mediated killing whose function is not fully explained by canonical apoptotic or non-apoptotic effector pathways. Our results further suggest that CASP8 engages additional downstream substrates or mechanisms to promote cytotoxic lymphocyte-induced cancer cell death.

Preprint server: bioRxiv
The authors list and abstract were imported from bioRxiv on 18 Jun 2026.

Stats

1-terrible, 9-excellent. How would you rate this preprint? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.