BioCentury
ARTICLE | Translation in Brief

The CDK5 checkpoint

Why CDK5 could be a new immuno-oncology target

August 18, 2016 7:00 AM UTC

Despite the clinical success of checkpoint inhibitors, immuno-oncologists still have an incomplete understanding of how the receptors and their ligands prevent antitumor immunity. In a new study, Case Western Reserve University researchers found mechanistic data that helps explain how PD-L1 is upregulated by tumors, and found a new target - cyclin dependent kinase 5 (CDK5) - that acts upstream of the ligand in cancers.

PD-L1 is one of the ligands for PD-1, a checkpoint inhibitor expressed on T cells that downregulates their activity. When tumors express PD-L1, the result is a dampened T cell-mediated immune response against the tumor. Inhibitors of PD-L1 and its receptor have produced dramatic effects in some patients, but not all tumors expressing PD-L1 respond to the treatments, and immuno-oncologists don't fully understand why...