Abstract Background: Glioma is a type of malignant cancer in the central nervous system. New predictive biomarkers have been investigated in recent years, but the clinical prognosis in glioma remains poor. The function of CPLX2 in glioma and the probable molecular mechanism of tumor suppression was the focus of this investigation. Methods: The glioma transcriptome profile is downloaded from The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) databases were performed to analyze the expression of CPLX2 in glioma. RT-qPCR was performed to detect the expression of CPLX2 in 68 glioma subjects, these patients who have been followed up. Kaplan-Meier survival analyses were done to evaluate the effect of CPLX2 on the prognosis of glioma patients. The CPLX2 knockdown and overexpressed cell lines were constructed to investigate the effect of CPLX2 on glioma. The cell growth, colony formation, and tumor formation in xenograft were performed. Results: The expression of CPLX2 was downregulated in glioma and negatively correlated to the grade of glioma. The higher expression of CPLX2 predicted a longer survival through the analysis of Kaplan-Meier survival curves. Overexpressed CPLX2 impaired tumorigenesis in glioma progression both in vivo and in vitro . Knocking down of CPLX2 promoted the proliferation of the glioma cells. The analysis of GSEA and co-expression analysis revealed that CPLX2 may affect the malignancy of glioma by regulating hypoxia and inflammation pathway. Conclusions: Our data indicated that CPLX2 functioned as a tumor suppressor and could be used as a potential prognostic marker in glioma.
OBJECTIVE There is a lack of effective drugs to treat the progression and recurrence of chordoma, which is widely resistant to treatment in chemotherapy. The authors investigated the functional and therapeutic relevance of the E1A-binding protein p300 (EP300) in chordoma. METHODS The expression of EP300 and vimentin was examined in specimens from 9 patients with primary and recurrent chordoma with immunohistochemistry. The biological functions of EP300 were evaluated with Cell Counting Kit-8, clonogenic assays, and transwell assays. The effects of EP300 inhibitors (C646 and SGC-CBP30) on chordoma cell motility were assessed with these assays. The effect of the combination of EP300 inhibitors and cisplatin on chordoma cells was evaluated with clonogenic assays. Reverse transcription quantitative polymerase chain reaction and Western blot techniques were used to explore the potential mechanism of EP300 through upregulation of the expression of vimentin to promote the progression of chordoma. RESULTS Immunohistochemistry analysis revealed a positive correlation between elevated EP300 expression levels and recurrence. The upregulation of EP300 stimulated the growth of and increased the migratory and invasive capabilities of chordoma cells, along with upregulating vimentin expression and consequently impacting their invasive properties. Conversely, EP300 inhibitors decreased cell proliferation and downregulated vimentin. Furthermore, the combination of EP300 inhibition and cisplatin exhibited an enhanced anticancer effect on chordoma cells, indicating that EP300 may influence chordoma sensitivity to chemotherapy. CONCLUSIONS These findings indicate that EP300 functions as an oncogene in chordoma. Targeting EP300 offers a novel approach to the development and clinical treatment of chordoma.