The neurofibromatosis type 2 gene product, merlin, reverses the F-actin cytoskeletal defects in primary human schwannoma cells
The neurofibromatosis type 2 gene product, merlin, reverses the F-actin cytoskeletal defects in primary human schwannoma cells
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DOI：
10.1128/mcb.22.4.1150-1157.2002
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发表时间：
2002-02-01
影响因子：
5.3
通讯作者：
Ratner, N
中科院分区：
文献类型：
--
作者：
Bashour, AM;Meng, JJ;Ratner, N
神经鞘瘤是一种散发性的神经纤维瘤病，占颅内肿瘤的8%，只能通过手术切除来治疗。大多数神经鞘瘤在NF 2肿瘤抑制基因中具有双等位基因突变。我们以前表明，神经鞘瘤来源的雪旺细胞表现出膜皱褶和异常细胞扩散时，板层粘连蛋白，基本的F-肌动蛋白细胞骨架缺陷的指示。在这里，我们将这些观察结果扩展到一大组散发性和NF 2相关肿瘤，并将其扩展到神经鞘瘤病衍生的肿瘤。NF 2突变与F-肌动蛋白异常相关，但形态学变化的程度与NF 2突变的类型无关。我们使用最近描述的分子策略，TAT介导的蛋白质转移，急性引入NF 2蛋白，梅林，到原代人神经鞘瘤细胞，试图扭转细胞骨架表型。通过引入TAT-merlin，可快速逆转具有已鉴定的NF 2突变的细胞的异常皱褶和细胞扩散。该效应对TAT-梅林亚型1（梅林的生长抑制亚型）具有特异性。TAT-merlin亚型2、TAT-merlin突变体（L 64 P）和缺乏达特的merlin在逆转细胞骨架表型方面无效。结果表明，梅林亚型1足以恢复正常肌动蛋白组织在NF 2缺陷的人肿瘤细胞，证明了梅林的关键作用，在NF 2表型。这些结果为NF 2小鼠模型中的表观遗传互补研究奠定了基础，并可能为评估merlin转导到患者中作为蛋白质治疗的效用的实验奠定了基础。
Schwannoma tumors, which occur sporadically and in patients with neurofibromatosis, account for 8% of intracranial tumors and can only be treated by surgical removal. Most schwannomas have biallelic mutations in the NF2 tumor suppressor gene. We previously showed that schwannoma-derived Schwann cells exhibit membrane ruffling and aberrant cell spreading when plated onto laminin, indicative of fundamental F-actin cytoskeletal defects. Here we expand these observations to a large group of sporadic and NF2-related tumors and extend them to schwannomatosis-derived tumors. Mutation at NF2 correlated with F-actin abnormalities, but the extent of morphological change did not correlate with the type of NF2 mutation. We used a recently described molecular strategy, TAT-mediated protein transfer, to acutely introduce the NF2 protein, merlin, into primary human schwannoma cells in an attempt to reverse the cytoskeletal phenotype. Abnormal ruffling and cell spreading by cells with identified NF2 mutations were rapidly reversed by introduction of TAT-merlin. The effect is specific to TAT-merlin isoform 1, the growth-suppressive isoform of merlin. TAT-merlin isoform 2, a TAT-merlin mutant (L64P), and merlin lacking TAT were ineffective in reversing the cytoskeletal phenotype. Results show that merlin isoform 1 is sufficient to restore normal actin organization in NF2-deficient human tumor cells, demonstrating a key role for merlin in the NF2 phenotype. These results lay the foundation for epigenetic complementation studies in NF2 mouse models and possibly for experiments to evaluate the utility of merlin transduction into patients as protein therapy.