Schepens Eye Research Institute, Harvard Medical School, 20 Staniford St., Boston, MA 02114, USA.
Mol Cell Biol. 2011 May;31(9):1788-99. doi: 10.1128/MCB.01321-10. Epub 2011 Feb 28.
In contrast to direct activation of platelet-derived growth factor (PDGF) receptor α (PDGFRα) via PDGF, indirect activation via growth factors outside the PDGF family failed to induce dimerization, internalization, and degradation of PDGFRα. Chronically activated, monomeric PDGFRα induced prolonged activation of Akt and suppressed the level of p53. These events were sufficient to promote both cellular responses (proliferation, survival, and contraction) that are intrinsic to proliferative vitreoretinopathy (PVR) and induce the disease itself. This signature signaling pathway appeared to extend beyond PVR since deregulating PDGFRα in ways that promote solid tumors also resulted in chronic activation of Akt and a decline in the level of p53.
与通过 PDGF 直接激活血小板衍生生长因子 (PDGF) 受体 α (PDGFRα) 相反,通过 PDGF 家族之外的生长因子间接激活未能诱导 PDGFRα 的二聚化、内化和降解。慢性激活的单体 PDGFRα 诱导 Akt 的持续激活,并抑制 p53 的水平。这些事件足以促进与增生性玻璃体视网膜病变 (PVR) 相关的细胞反应(增殖、存活和收缩),并诱导疾病本身。这种特征性信号通路似乎超出了 PVR,因为以促进实体瘤的方式使 PDGFRα 失调也导致 Akt 的慢性激活和 p53 水平的下降。