1. Academic Validation
  2. Cyclin G2 reverses immunosuppressive tumor microenvironment and potentiates PD-1 blockade in glioma

Cyclin G2 reverses immunosuppressive tumor microenvironment and potentiates PD-1 blockade in glioma

  • J Exp Clin Cancer Res. 2021 Aug 27;40(1):273. doi: 10.1186/s13046-021-02078-3.
Sen Li 1 Chenyang Zhao 1 Jinlan Gao 1 Xinbin Zhuang 1 Shuang Liu 1 Xuesha Xing 1 Qi Liu 1 Chen Chen 1 Shusen Wang 1 Yang Luo 2
Affiliations

Affiliations

  • 1 The Research Center for Medical Genomics, Key Laboratory of Medical Cell Biology, Ministry of Education, School of Life Science, China Medical University, No.77 Puhe Road, Shenyang North New Area, Liaoning Province, Shenyang, People's Republic of China.
  • 2 The Research Center for Medical Genomics, Key Laboratory of Medical Cell Biology, Ministry of Education, School of Life Science, China Medical University, No.77 Puhe Road, Shenyang North New Area, Liaoning Province, Shenyang, People's Republic of China. yluo@cmu.edu.cn.
Abstract

Background: Expression of aberrant cyclin G2 is a key factor contributing to Cancer biological processes, including glioma. However, the potential underlying mechanisms of cyclin G2 in the glioma tumor immune microenvironment remain unclear.

Methods: Co-immunoprecipitation (co-IP), in situ proximity ligation assay (PLA), and in vitro kinase assay were conducted to reveal the underlying mechanism by which cyclin G2 regulates Y10 phosphorylation of LDHA. Further, the biological roles of cyclin G2 in cell proliferation, migration, invasion capacity, Apoptosis, glycolysis, and immunomodulation were assessed through in vitro and in vivo functional experiments. Expressions of cyclin G2 and Foxp3 in glioma specimens was determined by immunohistochemistry.

Results: In this study, we found that cyclin G2 impeded the interaction between LDHA and FGFR1, thereby decreasing Y10 phosphorylation of LDHA through FGFR1 catalysis. Cyclin G2 inhibited proliferation, migration, invasion capacity, and glycolysis and promoted Apoptosis glioma cells via suppressing Y10 phosphorylation of LDHA. Moreover, we further verified that cyclin G2 reversed the immunosuppressive to antitumor immune microenvironment through inhibiting lactate production by glioma cells. Besides, cyclin G2 potentiated PD-1 blockade and exerted strong antitumor immunity in the glioma-bearing mice model.

Conclusions: Cyclin G2 acts as a potent tumor suppressor in glioma and enhances responses to immunotherapy. Our findings may be helpful in selecting glioma patients for immunotherapy trials in the future.

Keywords

Cyclin G2; Glioma; Immunosuppressive microenvironment; LDHA; PD-1.

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