A role for c-Abl/Arg in melanoma progression

描述（由申请人提供）：尽管经过35年的临床试验，任何化疗方案治疗转移性黑色素瘤的5年生存率几乎没有改善。在这里，我们证明了Abl激酶在黑色素瘤细胞中以前未被认识到的作用。我们发现c-Abl/Arg非受体酪氨酸激酶在原发性黑色素瘤和黑色素瘤细胞系中被激活，并促进增殖、存活、细胞-细胞粘附、迁移、侵袭和肺定植/转移。此外，c-Abl/Arg通过STAT3和mmp依赖通路促进基质侵袭；增加细胞-细胞黏附；并显著诱导转移抑制因子的降解。此外，靶向c-Abl/Arg和Raf/MEK/ERK通路的药物协同降低黑色素瘤的生存能力。基于这些新发现，我们假设c-Abl/Arg激活了与B-Raf合作的新途径，以促进黑色素瘤细胞的粘附、迁移、侵袭和转移。我们提出了一个全面的假设驱动的实验设计，将建立Abl激酶作为转移性黑色素瘤的新的和可利用的药物靶点。目的1将定义Abl激酶促进细胞粘附、迁移和侵袭的分子途径。为了实现我们的目标，我们将结合生化、分子和细胞生物学方法，使用RNAi、药理抑制剂、c-Abl/Arg的组成活性形式、救援实验、2D/3D细胞培养和黑色素瘤-内皮共培养来识别由c-Abl/Arg驱动的迁移、入侵和细胞-细胞粘附信号通路。Aim 2将验证c-Abl/Arg与abl非依赖性通路（如B-Raf）协同促进黑色素瘤细胞-细胞、粘附、迁移和侵袭的预测。最后，Aim 3将利用三种互补的方法来确定c-Abl/Arg促进转移的机制。一个新的GEM模型，发展转移性紫外线诱导的黑色素瘤，肺定植和自发转移异种移植模型将被用来验证阻断c-Abl/ arg依赖的信号通路抑制转移进展的预测。我们还将测试B-Raf和c-Abl/Arg抑制剂是否协同阻止含有B-Raf突变的黑色素瘤的转移。从该提案中获得的数据不仅使我们能够深入了解c-Abl/Arg驱动侵袭和转移的基本机制，而且还将导致临床研究测试c-Abl/Arg抑制剂治疗转移性疾病的疗效。

DESCRIPTION (provided by applicant): Despite 35 years of clinical trials, there has been little improvement in five-year survival rates with any chemotherapeutic regimen for the treatment of metastatic melanoma. Here, we demonstrate a previously unrecognized role for Abl kinases in melanoma cells. We found that c-Abl/Arg non-receptor tyrosine kinases are activated in primary melanomas and in melanoma cell lines, and promote proliferation, survival, cell-cell adhesion, migration, invasion, and lung colonization/metastasis. In addition, c-Abl/Arg promote matrigel invasion via STAT3 and MMP-dependent pathways; increase cell-cell adhesion; and dramatically induce degradation of a metastasis suppressor. Moreover, drugs targeting c-Abl/Arg and Raf/MEK/ERK pathways cooperate to decrease melanoma viability. Based on these novel findings, we hypothesize that c-Abl/Arg activate novel pathways that cooperate with B-Raf to promote melanoma cell-cell adhesion, migration, invasion, and metastasis. We propose a comprehensive hypothesis-driven experimental design that will establish Abl kinases as novel and exploitable drug targets for metastatic melanoma. Aim 1 will define molecular pathways by which Abl kinases promote cell-cell adhesion, migration, and invasion. To achieve our objective, we will combine biochemical, molecular, and cell biological approaches using RNAi, pharmacological inhibitors, constitutively active forms of c-Abl/Arg, rescue experiments, 2D/3D cell culture, and melanoma- endothelial co-cultures to identify migration, invasion, and cell-cell adhesion signaling pathways driven by c- Abl/Arg. Aim 2 will test the prediction that c-Abl/Arg cooperates with Abl-independent pathways (e.g. B-Raf) to promote melanoma cell-cell, adhesion, migration, and invasion. Finally, three complementary approaches will be utilized in Aim 3 to identify mechanisms by which c-Abl/Arg promote metastasis. A novel GEM model that develops metastatic UV-induced melanomas, and lung colonization and spontaneous metastasis xenograft models will be used to test the prediction that blocking c-Abl/Arg-dependent signaling pathways inhibits metastatic progression. We also will test whether B-Raf and c-Abl/Arg inhibitors cooperate to prevent metastasis of melanomas harboring B-Raf mutations. The data obtained from this proposal not only will allow us to gain insight into the fundamental mechanisms by which c-Abl/Arg drive invasion and metastasis, but also will lead to clinical studies testing the efficacy of c-Abl/Arg inhibitors for treating metastatic disease.