T cell Bim levels reflect responses to anti–PD-1 cancer therapy

Roxana S. Dronca, Xin Liu, Susan M. Harrington, Lingling Chen, Siyu Cao, Lisa A. Kottschade, Robert R. McWilliams, Matthew S. Block, Wendy K. Nevala, Michael A. Thompson, Aaron S. Mansfield, Sean S. Park, Svetomir N. Markovic, Haidong Dong

Research output: Contribution to journalArticlepeer-review


Immune checkpoint therapy with PD-1 blockade has emerged as an effective therapy for many advanced cancers; however, only a small fraction of patients achieve durable responses. To date, there is no validated blood-based means of predicting the response to PD-1 blockade. We report that Bim is a downstream signaling molecule of the PD-1 pathway, and its detection in T cells is significantly associated with expression of PD-1 and effector T cell markers. High levels of Bim in circulating tumor-reactive (PD-1+CD11ahiCD8+) T cells were prognostic of poor survival in patients with metastatic melanoma who did not receive anti–PD-1 therapy and were also predictive of clinical benefit in patients with metastatic melanoma who were treated with anti–PD-1 therapy. Moreover, this circulating tumor-reactive T cell population significantly decreased after successful anti–PD-1 therapy. Our study supports a crucial role of Bim in both T cell activation and apoptosis as regulated by PD-1 and PD-L1 interactions in effector CD8+ T cells. Measurement of Bim levels in circulating T cells of patients with cancer may provide a less invasive strategy to predict and monitor responses to anti–PD-1 therapy, although future prospective analyses are needed to validate its utility.

Original languageEnglish (US)
Article numbere86014
JournalJCI Insight
Issue number6
StatePublished - May 5 2016

ASJC Scopus subject areas

  • Medicine(all)


Dive into the research topics of 'T cell Bim levels reflect responses to anti–PD-1 cancer therapy'. Together they form a unique fingerprint.

Cite this