Cyclin D–CDK4 kinase destabilizes PD-L1 via cullin 3–SPOP to control cancer immune surveillance

  • Nature volume 553, pages 9195 (04 January 2018)
  • doi:10.1038/nature25015
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Treatments that target immune checkpoints, such as the one mediated by programmed cell death protein 1 (PD-1) and its ligand PD-L1, have been approved for treating human cancers with durable clinical benefit1,2. However, many patients with cancer fail to respond to compounds that target the PD-1 and PD-L1 interaction, and the underlying mechanism(s) is not well understood3,4,5. Recent studies revealed that response to PD-1–PD-L1 blockade might correlate with PD-L1 expression levels in tumour cells6,7. Hence, it is important to understand the mechanistic pathways that control PD-L1 protein expression and stability, which can offer a molecular basis to improve the clinical response rate and efficacy of PD-1–PD-L1 blockade in patients with cancer. Here we show that PD-L1 protein abundance is regulated by cyclin D–CDK4 and the cullin 3–SPOP E3 ligase via proteasome-mediated degradation. Inhibition of CDK4 and CDK6 (hereafter CDK4/6) in vivo increases PD-L1 protein levels by impeding cyclin D–CDK4-mediated phosphorylation of speckle-type POZ protein (SPOP) and thereby promoting SPOP degradation by the anaphase-promoting complex activator FZR1. Loss-of-function mutations in SPOP compromise ubiquitination-mediated PD-L1 degradation, leading to increased PD-L1 levels and reduced numbers of tumour-infiltrating lymphocytes in mouse tumours and in primary human prostate cancer specimens. Notably, combining CDK4/6 inhibitor treatment with anti-PD-1 immunotherapy enhances tumour regression and markedly improves overall survival rates in mouse tumour models. Our study uncovers a novel molecular mechanism for regulating PD-L1 protein stability by a cell cycle kinase and reveals the potential for using combination treatment with CDK4/6 inhibitors and PD-1–PD-L1 immune checkpoint blockade to enhance therapeutic efficacy for human cancers.

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We thank members of the Wei, Freeman, Sicinski, and Pandolfi laboratories for discussions. J.Z. is supported by the career transition award (1K99CA212292-01). W.W. is a Leukemia & Lymphoma Society research scholar. This work was supported in part by the National Institutes of Health (NIH) grants GM094777 and CA177910 (to W.W.), P01 CA080111, R01 CA202634 and R01 CA132740 (to P.S.), and P50CA101942 (to G.J.F).

Author information

Author notes

    • Jinfang Zhang
    • , Xia Bu
    • , Haizhen Wang
    • , Gordon J. Freeman
    • , Piotr Sicinski
    •  & Wenyi Wei

    These authors contributed equally to this work.

    • Gordon J. Freeman
    • , Piotr Sicinski
    •  & Wenyi Wei

    These authors jointly supervised this work.


  1. Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA

    • Jinfang Zhang
    • , Naoe Taira Nihira
    • , Yuyong Tan
    • , Yanpeng Ci
    • , Fei Wu
    • , Xiangpeng Dai
    • , Jianping Guo
    • , Yu-Han Huang
    •  & Wenyi Wei
  2. Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02215, USA

    • Xia Bu
    •  & Gordon J. Freeman
  3. Department of Cancer Biology, Dana-Farber Cancer Institute and Department of Genetics, Harvard Medical School, Boston, Massachusetts 02215, USA

    • Haizhen Wang
    • , Yan Geng
    • , Caoqi Fan
    •  & Piotr Sicinski
  4. Department of Urology, Shanghai Changhai Hospital, Second Military Medical University, Shanghai 200433, China

    • Yasheng Zhu
    • , Shancheng Ren
    •  & Yinghao Sun
  5. Department of Gastroenterology, the Second Xiangya Hospital of Central South University, Changsha 410011, China

    • Yuyong Tan
  6. School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China

    • Yanpeng Ci
  7. Department of Urology, Huashan Hospital, Fudan University, Shanghai 200040, China.

    • Fei Wu
  8. Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, School of Life Sciences, Peking University, Beijing 100871, China

    • Caoqi Fan


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J.Z., X.B. and H.W. performed most of the experiments with assistance from Y.Z., Y.G., N.T.N., Y.T., Y.C., F.W., X.D., J.G., Y.H., C.F., S.R. and Y.S. Y.Z., S.R., and Y.S. performed immunohistochemistry for human prostate cancer samples. Y.G., Y.T. and Y.C. helped with mice work. J.Z., X.B., H.W., G.J.F., P.S. and W.W. designed the experiments. G.J.F., P.S. and W.W. supervised the study. J.Z. and W.W. wrote the manuscript with help from X.B., H.W., P.S. and G.J.F. All authors commented on the manuscript.

Competing interests

G.J.F. has patents and pending royalties on the PD-1 pathway from Roche, Merck, Bristol-Myers-Squibb, EMD-Serono, Boehringer-Ingelheim, AstraZeneca, DAKO and Novartis. G.J.F. has served on advisory boards for CoStim, Novartis, Roche, Eli Lilly, Bristol-Myers-Squibb, Seattle Genetics, Bethyl Laboratories, Xios, and Quiet. P.S. is a consultant and a recipient of a research grant from Novartis. No potential conflicts of interests were disclosed by other authors.

Corresponding authors

Correspondence to Gordon J. Freeman or Piotr Sicinski or Wenyi Wei.

Reviewer Information Nature thanks J. Bartek, C. Klebanoff and S. Ogawa for their contribution to the peer review of this work.

Publisher's note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data

Supplementary information

PDF files

  1. 1.

    Supplementary Figure 1

    This file contains the source data for gels in Figures 1-4 and Extended Data Figures 1-9.

  2. 2.

    Life Sciences Reporting Summary

  3. 3.

    Gating strategy


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