Chen Weiliang, Xia Tongliang, Wang Donghai, Huang Bin, Zhao Peng, Wang Jian, Qu Xun, Li Xingang
Department of Otolaryngology, Qilu Hospital, Shandong University, Jinan, China.
Department of Neurosurgery, Qilu Hospital of Shandong University and Brain Science Research Institute, Shandong University, Jinan, China.
Oncotarget. 2016 Sep 20;7(38):62425-62438. doi: 10.18632/oncotarget.11515.
The brain microenvironment has emerged as an important component in malignant progression of human glioma. However, astrocytes, the most abundant glial cells in the glioma microenvironment, have as yet a poorly defined role in the development of this disease, particularly with regard to invasion. Here, we co-cultured human astrocytes with human glioma cell lines, U251 and A172, in an in vitro transwell system in order to ascertain their influence on migration and invasion of gliomas. mRNA and protein expression assays were subsequently used to identify candidate proteins mediating this activity. Astrocytes significantly increased migration and invasion of both U251 and A172 cells in migration and invasion (plus matrigel) assays. Membrane type 1 matrix metalloproteinase (MMP14) originating from glioma cells was identified in qRT-PCR as the most highly up-regulated member of the MMP family of genes (~ 3 fold, p < 0.05) in this system. A cytokine array and ELISA were used to identify interleukin-6 (IL-6) as a highly increased factor in media collected from astrocytes, especially under co-culture conditions. IL-6 was also the key cytokine inducing cytomembrane MMP14 expression, the active form of MMP14, in glioma cells. Knockdown of MMP14 with siRNA led to decreased migration and invasion. Taken together, our results indicated that cytomembrane MMP14 was induced by IL-6 secreted from astrocytes, thereby enhancing the migration and invasion of glioma cells through activation of MMP2. Therefore, this IL-6 and MMP14 axis between astrocytes and glioma cells may become a potential target for treatment of glioma patients.
脑微环境已成为人类胶质瘤恶性进展的重要组成部分。然而，星形胶质细胞作为胶质瘤微环境中最丰富的神经胶质细胞，在这种疾病的发展中所起的作用尚未明确界定，尤其是在侵袭方面。在这里，我们将人星形胶质细胞与人类胶质瘤细胞系U251和A172在体外Transwell系统中共培养，以确定它们对胶质瘤迁移和侵袭的影响。随后使用mRNA和蛋白质表达测定来鉴定介导这种活性的候选蛋白质。在迁移和侵袭（加基质胶）测定中，星形胶质细胞显著增加了U251和A172细胞的迁移和侵袭。在qRT-PCR中，源自胶质瘤细胞的膜型1基质金属蛋白酶（MMP14）被鉴定为该系统中MMP基因家族中上调程度最高的成员（约3倍，p<0.05）。使用细胞因子阵列和ELISA来鉴定白细胞介素-6（IL-6）是从星形胶质细胞收集的培养基中高度增加的因子，特别是在共培养条件下。IL-6也是诱导胶质瘤细胞中细胞膜MMP14表达（MMP14的活性形式）的关键细胞因子。用siRNA敲低MMP14导致迁移和侵袭减少。综上所述，我们的结果表明，细胞膜MMP14由星形胶质细胞分泌的IL-6诱导，从而通过激活MMP2增强胶质瘤细胞的迁移和侵袭。因此，星形胶质细胞与胶质瘤细胞之间的这种IL-6和MMP14轴可能成为治疗胶质瘤患者的潜在靶点。
