Loss of MEF2D expression inhibits differentiation and contributes to oncogenesis in rhabdomyosarcoma cells.
Loss of MEF2D expression inhibits differentiation and contributes to oncogenesis in rhabdomyosarcoma cells.
复制标题
DOI：
10.1186/1476-4598-12-150
复制
发表时间：
2013-11-27
期刊：
影响因子：
37.3
通讯作者：
Davie J
中科院分区：
文献类型：
--
作者：
Zhang M;Truscott J;Davie J
横纹肌肉瘤（RMS）是一种高度恶性的儿科癌症，是儿童软组织肿瘤中最常见的形式。RMS细胞具有骨骼肌细胞的许多特征，但不分化。因此，我们的研究集中在这些细胞中存在的阻碍肌生成的缺陷上。蛋白质和RNA分析鉴定了RMS细胞中MEF2D的缺失。MEF2D分别通过瞬时转染和选择稳定细胞系在RD和RH30细胞中表达，以证明观察到的肌肉分化的拯救。将诸如增殖测定、划痕测定和软琼脂测定的技术组合用于表达MEF2D的RH30细胞，以证明体外致癌生长的丧失，并将异种移植物测定用于确认体内肿瘤生长的丧失。在这里，我们表明，MEF2家族的成员之一的蛋白质所需的正常的肌肉发生，MEF2D，是在很大程度上不存在的RMS细胞系代表两个主要亚型的RMS以及来自胚胎RMS模型的原代细胞。我们发现MEF2D的下调是RMS细胞分化失败的主要原因。我们发现MyoD和肌细胞生成素与它们的二聚化伙伴E蛋白结合在RMS细胞中肌肉特异性基因的启动子上。然而，我们不能在任何测试的启动子处检测到MEF2D结合。我们发现外源性MEF2D表达可以激活肌肉特异性荧光素酶构建体，上调p21表达，并增加肌肉特异性基因表达，包括肌球蛋白重链的表达，肌球蛋白重链是骨骼肌分化的标志物。恢复MEF2D的表达还抑制体外增殖、细胞运动和锚定非依赖性生长。我们已经证实了MEF2D在肿瘤异种移植模型中对致瘤性的抑制作用，肿瘤生长完全消退。我们的数据表明，RMS细胞的致癌特性可以部分归因于MEF2D表达的丧失，MEF2D的恢复可能是一种有用的治疗策略，以减少致瘤性。
Rhabdomyosarcoma (RMS) is a highly malignant pediatric cancer that is the most common form of soft tissue tumors in children. RMS cells have many features of skeletal muscle cells, yet do not differentiate. Thus, our studies have focused on the defects present in these cells that block myogenesis. Protein and RNA analysis identified the loss of MEF2D in RMS cells. MEF2D was expressed in RD and RH30 cells by transient transfection and selection of stable cell lines, respectively, to demonstrate the rescue of muscle differentiation observed. A combination of techniques such as proliferation assays, scratch assays and soft agar assays were used with RH30 cells expressing MEF2D to demonstrate the loss of oncogenic growth in vitro and xenograft assays were used to confirm the loss of tumor growth in vivo. Here, we show that one member of the MEF2 family of proteins required for normal myogenesis, MEF2D, is largely absent in RMS cell lines representing both major subtypes of RMS as well as primary cells derived from an embryonal RMS model. We show that the down regulation of MEF2D is a major cause for the failure of RMS cells to differentiate. We find that MyoD and myogenin are bound with their dimerization partner, the E proteins, to the promoters of muscle specific genes in RMS cells. However, we cannot detect MEF2D binding at any promoter tested. We find that exogenous MEF2D expression can activate muscle specific luciferase constructs, up regulate p21 expression and increase muscle specific gene expression including the expression of myosin heavy chain, a marker for skeletal muscle differentiation. Restoring expression of MEF2D also inhibits proliferation, cell motility and anchorage independent growth in vitro. We have confirmed the inhibition of tumorigenicity by MEF2D in a tumor xenograft model, with a complete regression of tumor growth. Our data indicate that the oncogenic properties of RMS cells can be partially attributed to the loss of MEF2D expression and that restoration of MEF2D may represent a useful therapeutic strategy to decrease tumorigenicity.
登录
查看更多内容
影响因子：
5.3
作者：
Parker, Maura H.;Perry, Robert L. S.;Rudnicki, Michael A.
通讯作者：
Rudnicki, Michael A.
影响因子：
56.9
作者：
HALEVY, O;NOVITCH, BG;LASSAR, AB
通讯作者：
LASSAR, AB
DOI：
10.1073/pnas.080064097
发表时间：
2000-04-11
影响因子：
11.1
作者：
Lu, JR;McKinsey, TA;Olson, EN
通讯作者：
Olson, EN
影响因子：
11.4
作者：
Ohkawa, Y;Marfella, CGA;Imbalzano, AN
通讯作者：
Imbalzano, AN
影响因子：
11.2
作者：
Nishijo, Koichi;Chen, Qing-Rong;Keller, Charles
通讯作者：
Keller, Charles