Abstract 945: Oligodendrocytes might up-regulate the Invasiveness of glioblastoma cells via angiopoietin-2 signaling

Abstract Background & Aims: Glioblastoma (GBM, WHO Grade IV) is considered as the most lethal neoplasm of all solid cancers due to its inherent intensive invasiveness. GBM may arise de novo, or following progression from lower grade gliomas. Recently, solid tumor progression has been recognized as the product of an evolving crosstalk between the cancer cells and its surrounding glial cells. The intensive invasion activity of GBM cells might be regulated by surrounding normal cells such as oligodendrocytes or fibroblasts. In this study, we evaluated the interactive factors between GBM cells and normal glial cells to determine the role of oligodendrocytes in regulating the invasiveness of glioblastoma cells. Methods: Two GBM cell lines, T98G and U251, were used. Two oligodendrocyte cell lines, ODC1 and ODC2, were derived one each from surgical tissues of patients with low-grade glioma (WHO Grade II). Two fibroblasts cell lines, GF1 and GF2, were derived one each from surgical tissues of patients with GBM. Oligodendrocytes and fibroblasts were confirmed by immuno-histochemical staining. The invasive property of GBM cells was analyzed in the presence or absence of conditioned medium from oligodendrocytes or fibroblasts by wound-healing assay and Boyden chamber invasion assay. The proliferation ability of GBM cells was examined by MTT assay. Subsequently Cytokine array was used to examine the cytokines and growth factors in the conditioned medium from oligodendrocytes or fibroblasts. Results: Oligodendrocyte cells, ODC1 and ODC2 cells, significantly (p<0.01) increased the migration and invasion ability of GBM cells, T98G and U251. In contrast, fibroblasts, GF1 and GF2 cells, did not affect the migration and invasion ability of GBM cells. Cytokine array indicated that Angiopoietin-2 was found in the conditioned medium from oligodendrocytes, but not that from fibroblasts. Angiopoietin-2 significantly (p<0.01) increased the invasiveness of GBM, but not their proliferation ability. Conclusion: Oligodendrocytes might up-regulation of the invasiveness of GBM cells via angiopoietin-2 signaling pathway. Hence, angiopoietin-2 can be considered as a promising target for the treatment of malignant gliomas. Citation Format: Toshiyuki Kawashima. Oligodendrocytes might up-regulate the Invasiveness of glioblastoma cells via angiopoietin-2 signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 945. doi:10.1158/1538-7445.AM2017-945