Table_2_P4HA1 Regulates CD31 via COL6A1 in the Transition of Glioblastoma Stem-Like Cells to Tumor Endothelioid Cells.xlsx

Glioblastoma multiforme (GBM) is a common intracranial malignancy characterized by abundant and aberrant vasculature. The efficiency of existing antivascular treatments remains unsatisfactory. The transition of glioblastoma stem-like cells (GSCs) into tumor endothelioid cells (ECs) has been thought to cause glioma neovascularization and anti-angiogenesis tolerance, but the mechanisms regulating glioma transdifferentiation remains unclear. Our previous study found that P4HA1 regulates GSCs vascular mimicry in a hypoxic microenvironment, but the detailed molecular mechanism has not been determined. In this study, candidate protein COL6A1 was screened by mass spectrometry. In vitro experiments show that P4HA1 regulates the expression of CD31 via COL6A1, with the levels of expression of P4HA1, COL6A1 and the vascular endothelial molecular markers CD31 showing positive correlations in vivo assay. Altering the expression of P4HA1 in GSCs altered the expression of COL6A1 and CD31, thereby inducing glioma angiogenesis. In conclusion, this study revealed that the P4HA1/COL6A1 axis modulates the transdifferentiation process of GSCs into ECs. Interrupting this signaling axis can inhibit glioma angiogenesis, suggesting that this axis may be a novel target for antivascular therapy in patients with glioma.

多形性胶质母细胞瘤（Glioblastoma multiforme, GBM）是一类常见的颅内恶性肿瘤，以富含异常血管网络为典型病理特征。现有抗血管治疗方案的临床疗效仍欠佳。既往研究认为，胶质母细胞瘤干细胞样细胞（glioblastoma stem-like cells, GSCs）向肿瘤内皮样细胞（tumor endothelioid cells, ECs）转分化，是驱动胶质瘤新生血管生成并介导抗血管生成耐受的关键机制之一，但调控胶质瘤细胞转分化的具体分子通路仍未明确。本课题组前期研究发现，P4HA1可在缺氧微环境中调控GSCs的血管生成拟态，但具体的分子机制尚未阐明。本研究通过质谱分析筛选得到候选蛋白COL6A1，体外实验证实P4HA1可通过COL6A1调控CD31的表达；体内实验结果显示，P4HA1、COL6A1与血管内皮分子标记物CD31的表达水平呈显著正相关。在GSCs中干预P4HA1的表达水平，可同步调控COL6A1与CD31的表达，进而介导胶质瘤血管生成。综上，本研究揭示了P4HA1/COL6A1信号轴可调控GSCs向ECs转分化的过程；阻断该信号通路可显著抑制胶质瘤血管生成，提示该轴有望成为胶质瘤患者抗血管治疗的全新潜在靶点。