Abstract

Glioblastoma (GBM), the most frequent primary tumor of the central nervous system, has a median survival of 14.6 months. 4-Methylumbelliferone (4MU) is a coumarin derivative widely used as a hyaluronan synthesis inhibitor with proven antitumor activity and without toxic effects reported. We aim to evaluate the antitumor effect of 4MU alone or combined with temozolomide (TMZ) on a GBM cell line, its absence of toxicity on brain cells and its selectivity for tumor cells. The antitumor effect of 4MU alone or combined with TMZ was evaluated on GL26 cells by assessing the metabolic activity through the XTT assay, cell proliferation by BrdU incorporation assay, migration by the wound healing assay, cell death by fluorescein diacetate/propidium iodide (FDA/PI) staining, apoptosis by membrane asymmetry and DNA fragmentation and metalloproteinase activity by zymography. The levels of hyaluronan and its capacity to counteract the effects of 4MU and the expression of RHAMM and CD44 were also determined. The toxicity and selectivity of 4MU were determined by XTT assay and PI staining on normal brain primary cell culture (NBPC-GFP) and GL26/NBPC-GFP cocultures. The GL26 cells expressed RHAMM but not CD44 while synthetized hyaluronan. 4MU decreased hyaluronan synthesis, diminished proliferation and induced apoptosis while reducing cell migration and the activity of metalloproteinases, which was restored by addition of hyaluronic acid. Furthermore, 4MU sensitized GL26 cells to the TMZ effect and showed selective toxicity on tumor cells without exhibiting neurotoxic effects. We demonstrated for the first time the cytotoxic effect of 4MU on GBM cells, highlighting its potential usefulness to improve GBM treatment.

中文翻译：

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4-甲基伞形酮作为胶质母细胞瘤模型的强效和选择性抗肿瘤药物。

摘要

胶质母细胞瘤 (GBM) 是中枢神经系统最常见的原发性肿瘤，中位生存期为 14.6 个月。4-Methylumbelliferone (4MU) 是一种香豆素衍生物，广泛用作透明质酸合成抑制剂，具有经证实的抗肿瘤活性且无毒性作用报道。我们旨在评估 4MU 单独或与替莫唑胺 (TMZ) 联合对 GBM 细胞系的抗肿瘤作用、对脑细胞无毒性及其对肿瘤细胞的选择性。通过 XTT 测定评估代谢活性、BrdU 掺入测定评估细胞增殖、伤口愈合测定迁移、二乙酸荧光素/碘化丙啶 (FDA/ PI）染色，细胞凋亡通过膜不对称和 DNA 片段化和酶谱法检测金属蛋白酶活性。还测定了透明质酸的水平及其抵消 4MU 作用的能力以及 RHAMM 和 CD44 的表达。4MU 的毒性和选择性通过 XTT 测定和 PI 染色对正常脑原代细胞培养物 (NBPC-GFP) 和 GL26/NBPC-GFP 共培养物进行测定。GL26 细胞在合成透明质酸时表达 RHAMM 但不表达 CD44。4MU减少透明质酸合成，减少增殖并诱导细胞凋亡，同时减少细胞迁移和金属蛋白酶的活性，通过添加透明质酸恢复。此外，4MU 使 GL26 细胞对 TMZ 效应敏感，并对肿瘤细胞表现出选择性毒性，而没有表现出神经毒性作用。