# Novel mechanisms regulating PD-1 signaling and function > **NIH NIH R01** · COLUMBIA UNIVERSITY HEALTH SCIENCES · 2022 · $442,212 ## Abstract ABSTRACT Cancer immunotherapies represent a powerful and newly emergent therapeutic paradigm, both because of their durable clinical responses and applicability to a wide variety of tumors. Immune checkpoint therapies block inhibitory receptors on T cells in order to augment anti-tumor immune responses. Programmed cell death protein 1 (PD-1) is a critical inhibitory checkpoint for T cells. The identification and clearance of malignant cells can be brought about by antibodies which block PD-1. Despite the success of these antibodies, most patients do not respond to PD-1 blockade, and many experience immune-related adverse events. New studies indicate that some 5-10% of patients demonstrate accelerated cancer progression after anti-PD-1 treatment, in contrast to predicted responses based on current mechanistic models. With both the potential successes and failures of PD-1 being so significant, the need to understand PD-1 signaling is evidently very urgent, both for explaining the mechanism of clinical responses and for developing therapeutics that go beyond simply interfering with ligand binding. We have developed a new method to analyze mass spectrometry data and discovered novel effectors of PD-1 signaling. Most excitingly, we have identified multiple candidates, including the kinase VRK2 which we intend to investigate further. The overarching goal of this proposal is to study PD-1-associated kinases in order to better define novel signaling pathways and to uncover T cell-intrinsic mechanisms which contribute to resistance to PD-1 blockade. In the first aim, we will discover the molecular mechanism by which VRK2 controls PD-1 signaling in T cells. We will perform structure-function analyses to test the hypothesis that VRK2’s enzymatic domain is required for mediating specific PD-1 functions and utilize biochemical and imaging approaches to uncover the contribution made by VRK2 interactions with MAPK8IP1 and MAP3K7 towards PD-1 signaling. In the second aim we will test the hypothesis that VRK2 is required for PD-1 inhibition of cellular functions in vivo. We will utilize VRK2 KO mice to uncover the mechanism by which VRK2 supports tumor growth in vivo in the context of PD-1 blockade and resistance. Given the large impact of PD- 1 on public health, the proposed work is incredibly significant. ## Key facts - **NIH application ID:** 10522391 - **Project number:** 2R01AI125640-07A1 - **Recipient organization:** COLUMBIA UNIVERSITY HEALTH SCIENCES - **Principal Investigator:** Adam Mor - **Activity code:** R01 (R01, R21, SBIR, etc.) - **Funding institute:** NIH - **Fiscal year:** 2022 - **Award amount:** $442,212 - **Award type:** 2 - **Project period:** 2016-06-20 → 2027-05-31 ## Primary source NIH RePORTER: https://reporter.nih.gov/project-details/10522391 ## Citation > US National Institutes of Health, RePORTER application 10522391, Novel mechanisms regulating PD-1 signaling and function (2R01AI125640-07A1). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10522391. Licensed CC0. --- *[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*