In recent years, the survey of metabolic glutamate receptor 4 (GRM4) in tumor biology has been gradually concerned. There are currently few studies on GRM4 in osteosarcoma, and the biological function is not clear. Analysis of TCGA database showed that there was no substantial deviation in the expression of GRM4 between osteosarcoma and normal tissues. In the subsequent experiments, there is no significant difference in either mRNA or protein levels among immortalized human osteoblasts and various osteosarcoma cells. With the overexpression of GRM4, cell proliferation, migration and invasion were inhibited obviously. It was further revealed that GRM4 can interact with CBX4 to restrict the nuclear localization of CBX4 and affect the transcriptional activity of HIF-1α. This is the evidence supporting the interaction between GRM4 and CBX4, which could inhibit the malignant behavior of osteosarcoma cells through the GRM4/CBX4/HIF-1α signaling pathway.

中文翻译：

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GRM4通过与CBX4相互作用抑制人骨肉瘤细胞的增殖，迁移和侵袭。

近年来，在肿瘤生物学中对代谢谷氨酸受体4（GRM4）的研究已逐渐引起人们的关注。目前关于骨肉瘤中GRM4的研究很少，其生物学功能尚不清楚。TCGA数据库的分析表明，骨肉瘤与正常组织之间的GRM4表达没有实质性差异。在随后的实验中，永生化的人类成骨细胞和各种骨肉瘤细胞之间的mRNA或蛋白质水平均无显着差异。随着GRM4的过表达，细胞增殖，迁移和侵袭被明显抑制。进一步揭示GRM4可与CBX4相互作用以限制CBX4的核定位并影响HIF-1α的转录活性。这是支持GRM4和CBX4之间相互作用的证据，