2. Academic Validation
  3. Targeting HTR2B suppresses non-functioning pituitary adenoma growth and sensitizes cabergoline treatment via inhibiting Gαq/PLC/PKCγ/STAT3 axis

Targeting HTR2B suppresses non-functioning pituitary adenoma growth and sensitizes cabergoline treatment via inhibiting Gαq/PLC/PKCγ/STAT3 axis

  • Neuro Oncol. 2024 Jul 11:noae130. doi: 10.1093/neuonc/noae130.
Shaojian Lin 1 2 3,  Liangbo Wang 2,  Changxi Han 1,  Yuting Dai 4,  Changsheng Li 1,  Yanting Liu 1,  Bo Zhang 1,  Ning Huang 2,  Anke Zhang 5,  Tao Zhang 2,  Yu Wang 6,  Jing Xie 7,  Hao Tang 1,  Yijun Cheng 1,  Hong Yao 1,  Meiqing Lou 8,  Li Xue 1 3,  Zhe Bao Wu 1 2 3
Affiliations

Affiliations

  • 1 Department of Neurosurgery, Center of Pituitary Tumor, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
  • 2 Department of Neurosurgery, First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.
  • 3 Department of Neurosurgery, Center for Immune-Related Diseases at Shanghai Institute of Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
  • 4 Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
  • 5 Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
  • 6 Department of Neurosurgery, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
  • 7 Department of Pathology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
  • 8 Department of Neurosurgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
PMID: 38989697 DOI: 10.1093/neuonc/noae130
Abstract

Background: Managing non-functioning pituitary adenomas (NFPAs) is difficult due to limited drug treatments. Cabergoline's (CAB) effectiveness for NFPAs is debated. This study explores the role of HTR2B in NFPAs and its therapeutic potential.

Methods: We conducted screening of bulk RNA-sequencing data to analyze HTR2B expression levels in NFPA samples. In vitro and in vivo experiments were performed to evaluate the effects of HTR2B modulation on tumor growth and cell cycle regulation. Mechanistic insights into the HTR2B-mediated signaling pathway were elucidated using pharmacological inhibitors and molecular interaction assays.

Results: Elevated HTR2B expression was detected in NFPA samples, which was associated with increased tumor survival. Inhibition of HTR2B activity resulted in the suppression of tumor growth through modulation of the G2M cell cycle. The inhibition of HTR2B with PRX-08066 was found to block STAT3 phosphorylation and nuclear translocation by interfering with the Gαq/PLC/PKC pathway. A direct interaction between PKC-γ and STAT3 was critical for STAT3 activation. CAB was shown to activate pSTAT3 via HTR2B, reducing its therapeutic potential. However, the combination of an HTR2B antagonist with CAB significantly inhibited tumor cell proliferation in HTR2B-expressing pituitary tumor cell lines, a xenografted pituitary tumor model, and patient-derived samples. Analysis of patient-derived data indicated that a distinct molecular pattern characterized by upregulated HTR2B/PKC-γ and downregulated BTG2/GADD45A may benefit from combination treatment with CAB and PRX-08066.

Conclusions: HTR2B is a potential therapeutic target for NFPAs, and its inhibition could improve CAB efficacy. A dual therapy approach may be beneficial for NFPA patients with high HTR2B expression.

Keywords

Cabergoline; Gαq/PLC/PKC-γ; HTR2B; Pituitary adenomas; STAT3.

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