Uhl Martin, Aulwurm Steffen, Wischhusen Jörg, Weiler Markus, Ma Jing Ying, Almirez Ramona, Mangadu Ruban, Liu Yu-Wang, Platten Michael, Herrlinger Ulrich, Murphy Alison, Wong Darren H, Wick Wolfgang, Higgins Linda S, Weller Michael
Laboratory of Molecular Neuro-Oncology, Department of General Neurology, Hertie Institute for Clinical Brain Research, University of Tübingen, School of Medicine, Tübingen, Germany.
Cancer Res. 2004 Nov 1;64(21):7954-61. doi: 10.1158/0008-5472.CAN-04-1013.
The cytokine transforming growth factor (TGF)-beta, by virtue of its immunosuppressive and promigratory properties, has become a major target for the experimental treatment of human malignant gliomas. Here we characterize the effects of a novel TGF-beta receptor (TGF-betaR) I kinase inhibitor, SD-208, on the growth and immunogenicity of murine SMA-560 and human LN-308 glioma cells in vitro and the growth of and immune response to intracranial SMA-560 gliomas in syngeneic VM/Dk mice in vivo. SD-208 inhibits the growth inhibition of TGF-beta-sensitive CCL64 cells mediated by recombinant TGF-beta1 or TGF-beta2 or of TGF-beta-containing glioma cell supernatant at an EC(50) of 0.1 mumol/L. SD-208 blocks autocrine and paracrine TGF-beta signaling in glioma cells as detected by the phosphorylation of Smad2 or TGF-beta reporter assays and strongly inhibits constitutive and TGF-beta-evoked migration and invasion, but not viability or proliferation. Peripheral blood lymphocytes or purified T cells, cocultured with TGF-beta-releasing LN-308 glioma cells in the presence of SD-208, exhibit enhanced lytic activity against LN-308 targets. The release of interferon gamma and tumor necrosis factor alpha by these immune effector cells is enhanced by SD-208, whereas the release of interleukin 10 is reduced. SD-208 restores the lytic activity of polyclonal natural killer cells against glioma cells in the presence of recombinant TGF-beta or of TGF-beta-containing glioma cell supernatant. The oral bioavailability of SD-208 was verified by demonstrating the inhibition of TGF-beta-induced Smad phosphorylation in spleen and brain. Systemic SD-208 treatment initiated 3 days after the implantation of SMA-560 cells into the brains of syngeneic VM/Dk mice prolongs their median survival from 18.6 to 25.1 days. Histologic analysis revealed no difference in blood vessel formation, proliferation, or apoptosis. However, animals responding to SD-208 showed an increased tumor infiltration by natural killer cells, CD8 T cells, and macrophages. These data define TGF-beta receptor I kinase inhibitors such as SD-208 as promising novel agents for the treatment of human malignant glioma and other conditions associated with pathological TGF-beta activity.
细胞因子转化生长因子（TGF）-β凭借其免疫抑制和促迁移特性，已成为人类恶性胶质瘤实验性治疗的主要靶点。在此，我们阐述了一种新型TGF-β受体（TGF-βR）I激酶抑制剂SD-208对小鼠SMA-560和人LN-308胶质瘤细胞体外生长及免疫原性的影响，以及对同基因VM/Dk小鼠颅内SMA-560胶质瘤生长及免疫反应的影响。SD-208在0.1 μmol/L的半数有效浓度（EC50）下，可抑制重组TGF-β1或TGF-β2介导的对TGF-β敏感的CCL64细胞的生长抑制，或含TGF-β的胶质瘤细胞上清液介导的生长抑制。通过Smad2磷酸化检测或TGF-β报告基因检测发现，SD-208可阻断胶质瘤细胞中的自分泌和旁分泌TGF-β信号传导，并强烈抑制组成性和TGF-β诱导的迁移与侵袭，但不影响细胞活力或增殖。在SD-208存在的情况下，与释放TGF-β的LN-308胶质瘤细胞共培养的外周血淋巴细胞或纯化T细胞，对LN-308靶细胞的裂解活性增强。SD-208可增强这些免疫效应细胞释放干扰素γ和肿瘤坏死因子α，而白细胞介素10的释放则减少。在重组TGF-β或含TGF-β的胶质瘤细胞上清液存在的情况下，SD-208可恢复多克隆自然杀伤细胞对胶质瘤细胞的裂解活性。通过证明对脾脏和大脑中TGF-β诱导的Smad磷酸化的抑制，验证了SD-208的口服生物利用度。在将SMA-560细胞植入同基因VM/Dk小鼠脑内3天后开始进行全身性SD-208治疗，可将其平均生存期从18.6天延长至25.1天。组织学分析显示，血管形成、增殖或凋亡方面无差异。然而，对SD-208有反应的动物显示自然杀伤细胞、CD8 T细胞和巨噬细胞对肿瘤的浸润增加。这些数据表明，诸如SD-208之类的TGF-β受体I激酶抑制剂是治疗人类恶性胶质瘤及其他与病理性TGF-β活性相关病症的有前景的新型药物。
