S1P/S1PR3 axis promotes aerobic glycolysis by YAP/c-MYC/PGAM1 axis in osteosarcoma

Abstract

BackgroundOsteosarcoma (OS) is a malignant tumor mainly occurring in young people. Due to the limited effective therapeutic strategies, OS patients cannot achieve further survival improvement. G-protein-coupled receptors (GPCRs) constitute the largest family of cell membrane receptors and consequently hold the significant promise for tumor imaging and targeted therapy. We aimed to explore the biological functions of Sphingosine 1-phosphate receptor 3 (S1PR3), one of the members of GPCRs family, in OS and the possibility of S1PR3 as an effective target for the treatment of osteosarcoma.MethodsThe quantitative real time PCR (qRT-PCR) and western blotting were used to analyze the mRNA and protein expressions. Cell counting kit-8 (CCK8), colony formation assay and cell apoptosis assay were performed to test the cellular proliferation in vitro. Subcutaneous xenograft mouse model was generated to evaluate the functions of S1PR3 in vivo. RNA sequencing was used to compare gene expression patterns between S1PR3-knockdown and control MNNG-HOS cells. In addition, metabolic alternations in OS cells were monitored by XF96 metabolic flux analyzer. Co-immunoprecipitation (Co-IP) assay was used to explore the interaction between Yes-associated protein (YAP) and c-MYC. Chromatin immunoprecipitation was used to investigate the binding capability of PGAM1 and YAP or c-MYC. Moreover, the activities of promoter were determined by the luciferase reporter assay.FindingsS1PR3 and its specific ligand Sphingosine 1-phosphate (S1P) were found elevated in OS, and the higher expression of S1PR3 was correlated with the poor survival rate. Moreover, our study has proved that the S1P/S1PR3 axis play roles in proliferation promotion, apoptosis inhibition, and aerobic glycolysis promotion of osteosarcoma cells. Mechanistically, the S1P/S1PR3 axis inhibited the phosphorylation of YAP and promoted the nuclear translocation of YAP, which contributed to the formation of the YAP–c-MYC complex and enhanced transcription of the important glycolysis enzyme PGAM1. Moreover, the S1PR3 antagonist TY52156 exhibited in vitro and in vivo synergistic inhibitory effects with methotrexate on OS cell growth.InterpretationOur study unveiled a role of S1P, a bioactive phospholipid, in glucose metabolism reprogram through interaction with its receptor S1PR3. Targeting S1P/S1PR3 axis might serve as a potential therapeutic target for patients with OS.FundThis research was supported by National Natural Science Foundation of China (81472445 and 81672587).

Phosphoglycerate mutase 1 in cancer: A promising target for diagnosis and therapy

“…PGAM1 has a number of copies, therefore, demonstrate as a progenitor of PGAM2. The human PGAM‐B shows an overall similarity of approximately 48% with yeast PGAM …”

“…According to Warburg, cancer cells primarily produce energy by aerobic glycolysis comparatively than oxidative phosphorylation. When S1PR3 was exhausted in OS cells, a significant increase in mitochondrial respiration was found that showed that the S1P/S1PR3 axis dedicated toward the activation of Warburg's effect in osteosarcoma cells …”

“…S1P/S1PR3 axis donated to the production of the YAP–c‐MYC complex through phosphorylation, inhibition, and nuclear translocation of YAP that resulted in increased transcription of the essential glycolytic enzyme PGAM1. YAP‐activated PGAM1 transcription was clearly repressed by the knockdown of c‐MYC and showed that through YAP/c‐YMC complex, S1PR3 regulated the PGAM1 expression in OS cells …”

“…The human PGAM-B shows an overall similarity of approximately 48% with yeast PGAM. 16,24 3 | CATALYTIC MECHANISM OF PGAM1 PGAM1 is a brain isoform of phosphoglycerate mutase. It catalyzes the isomerization of 3-phosphoglycerate into downstream glycolytic product 2-phosphoglycerate with intermediate product formation of 2, 3-bisphosphoglycerate (2, 3-BPG) ( Figure 1).…”

“…When S1PR3 was exhausted in OS cells, a significant increase in mitochondrial respiration was found that showed that the S1P/S1PR3 axis dedicated toward the activation of Warburg's effect in osteosarcoma cells. 24 Hippo signaling cascade is an extremely conserved tumor suppressor signaling that controls the organ size. In mammals, it comprises two onco suppressive kinases (MST1/2, LATS1/2) with their associated protein/paralog (YAP/TAZ).…”