The protein tyrosine phosphatase SHP-2 is required for EGFRvIII oncogenic transformation in human glioblastoma cells.
The protein tyrosine phosphatase SHP-2 is required for EGFRvIII oncogenic transformation in human glioblastoma cells.
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DOI：
10.1016/j.yexcr.2009.05.001
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发表时间：
2009-08-15
影响因子：
3.7
通讯作者：
O'Rourke DM
中科院分区：
文献类型：
--
作者：
Zhan Y;Counelis GJ;O'Rourke DM
致癌性EGFRvIII是一种天然存在的癌蛋白，在约40-50%的人胶质母细胞瘤中表达，特别是那些新生的胶质母细胞瘤。为了了解这种癌蛋白改变转化表型的分子机制，并且由于我们先前的工作表明SHP-2蛋白酪氨酸磷酸酶活性调节EGFRvIII激活和下游信号传导，我们通过使用PTEN缺陷的U87MG.EGFRvIII和PTEN完整的LN229.EGFRvIII细胞来检测SHP-2是否在EGFRvIII诱导的肿瘤发生中起作用。通过Shp-2 siRNA抑制SHP-2表达抑制了这些EGFRvIII转化的GBM细胞的细胞生长、转化和改变的形态。SHP-2的PTPase-inactive形式SHP-2 C459 S的异位表达，而不是其野生型SHP-2或两种SH 2结构域突变体中的任一种，废除了在软琼脂和裸鼠中表达EGFRvIII的胶质母细胞瘤的转化。SHP-2 C459 S细胞生长缓慢，并表现出更扁平的形态与更有组织的肌动蛋白应力纤维在充分的生长和低血清条件下。此外，shp-2 +/-和-/-小鼠胚胎成纤维细胞（MEF）不能被EGFRvIII转化，而shp-2 +/+ MEF在引入EGFRvIII后显示出完全转化的表型，再次表明在EGFRvIII转化中需要功能性SHP-2。此外，SHP-2蛋白激酶活性抑制剂NSC-87877抑制两种GBM细胞系中的内源性SHP-2活性、Erk磷酸化和转化。EGFRvIII表达将SHP-2募集到受体复合物中以抑制信号，并且还增加了SHP-2在Tyr 542处的磷酸化。SHP-2 C459 S或shp-2 siRNA对EGFRvIII诱导的细胞生长和转化的抑制作用是通过其在这些GBM细胞的不同阶段阻断细胞周期进程的能力介导的。这些数据表明，在这两种GBM细胞系中，SHP-2在Tyr 542处磷酸化的差异活化可能导致不同的PTK活性增加和细胞周期进展的不同机制，并且SHP-2，特别是其PTK活性，在EGFR vIII介导的转化中起关键作用。
Oncogenic EGFRvIII is a naturally occurring oncoprotein and is expressed in about 40–50% of human glioblastomas, particular those that arise de novo. To understand the molecular mechanisms by which this oncoprotein alters transforming phenotypes, and since our previous work indicated that SHP-2 protein tyrosine phosphatase activity modulated EGFRvIII activation and downstream signaling, we examined whether SHP-2 plays a role in EGFRvIII-induced oncogenesis by using both PTEN-deficient U87MG.EGFRvIII and PTEN-intact LN229.EGFRvIII cells. Inhibition of SHP-2 expression by Shp-2 siRNA inhibited cell growth, transformation and altered morphology of these EGFRvIII transformed GBM cells. Ectopic expression of a PTPase-inactive form of SHP-2, SHP-2 C459S, but not its wild-type SHP-2 or either of two SH2 domain mutants, abrogated transformation of EGFRvIII-expressing glioblastomas in soft agar and in nude mice. SHP-2 C459S cells grew slower and exhibited a more flattened morphology with more organized actin stress fibers under both full growth and low serum conditions. Furthermore, shp-2 +/− and −/− mouse embryonic fibroblasts (MEFs) could not be transformed by EGFRvIII while shp-2 +/+ MEFs displayed a fully transformed phenotype upon introduction of EGFRvIII, again indicating a requirement for functional SHP-2 in EGFRvIII transformation. Moreover, the SHP-2 PTPase activity inhibitor NSC-87877 inhibited endogenous SHP-2 activity, Erk phosphorylation and transformation in both GBM cell lines. EGFRvIII expression recruited SHP-2 to the receptor complex to transduce signals and also increased SHP-2 phosphorylation at Tyr542. Inhibition of EGFRvIII-induced cell growth and transformation by SHP-2 C459S or shp-2 siRNA was mediated by its ability to block cell cycle progression at different phases in these GBM cells. These data indicate that differential activation of SHP-2 phosphorylation at Tyr542 in these two GBM cell lines likely results in increased different PTPase activity and distinct mechanisms of cell cycle progression andSHP-2, in particular its PTPase activity, plays a critical role in EGFRvIII-mediated transformation.
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影响因子：
5.3
作者：
Kapoor, GS;Zhan, Y;O'Rourke, DM
通讯作者：
O'Rourke, DM
影响因子：
8
作者：
Lu, XL;Qu, CK;Feng, GS
通讯作者：
Feng, GS
DOI：
10.1073/pnas.90.6.2197
发表时间：
1993-03-15
影响因子：
11.1
作者：
AHMAD, S;BANVILLE, D;SHEN, SH
通讯作者：
SHEN, SH
影响因子：
11.2
作者：
Bentires-Alj, M;Paez, JG;Neel, BG
通讯作者：
Neel, BG
DOI：
10.1073/pnas.89.23.11239
发表时间：
1992-12-01
影响因子：
11.1
作者：
FREEMAN, RM;PLUTZKY, J;NEEL, BG
通讯作者：
NEEL, BG