WP1130

Degrasyn (WP1130)是一种选择性的去泛素化酶(DUB: USP5， UCH-L1， USP9x， USP14， UCH37)抑制剂，也抑制Bcr/Abl，也是一种JAK2传感器(不影响20S蛋白酶体)和转录激活剂(STAT)。 In addition to inducing rapid down-regulation of Bcr/Abl without affecting Bcr or c-Abl, WP1130 also regulates the stability of Jak2 and c-Myc without affecting other kinases (HER1, HER2, c-Kit, FAK, ERK1, ERK2, Akt, Btk, Src and Src-related kinases) or transcription factors (wild-type p53, STAT1, STAT3, STAT5, c-Jun, NF-κB, and Max). Unlike adaphostin and Trisenox, WP1130 induces down-regulation of Bcr/Abl within 60 minutes. WP1130 is more effective in inducing apoptosis of myeloid and lymphoid tumor cells with IC50 of ~0.5-2.5 μM compared with normal CD34⁺ hematopoietic precursors, dermal fibroblasts, or endothelial cells with IC50 of ~5-10 μM. WP1130 (5 μM) specifically and rapidly down-regulates both wild-type and T315I mutant Bcr/Abl protein without affecting bcr/abl gene expression or engaging the proteasomal degradation pathway in chronic myelogenous leukemia (CML) cells, accompanied by induction of apoptosis. WP1130 is more effective in reducing leukemic cell colony formation compared with normal progenitor cells, and effective against primary leukemic cells harboring the T315I mutation. WP1130 induces rapid proteasomal-dependent degradation of c-Myc protein in MM-1 multiple myeloma and other tumor cell lines, correlated with tumor growth inhibition. Unlike AG490, WP1130 acts as a partly selective deubiquitinase (DUB) inhibitor to induce a rapid and marked accumulation of polyubiquitinated (K48/K63-linked) proteins into juxtanuclear aggresomes without affecting proteasome activity. WP1130 (5 μM) directly inhibits DUB activity of USP9x, USP5, USP14, UCH-L1, and UCH37, but not UCH-L3, resulting in downregulation of antiapoptotic and upregulation of proapoptotic proteins, such as MCL-1 and p53. Administration of WP1130 inhibits the growth of K562 tumors as well as both wildtype Bcr/Abl and T315I mutant Bcr/Abl-expressing BaF/3 cells transplanted into nude mice. Consistent with the down-regulation of c-Myc, WP1130 displays potent inhibitory activity against A375 melanoma tumors established in nude mice. WP1130 has an advantage over imatinib mesylate in that its activity is not inhibited by a variety of Abl kinase mutations, including T315I. Degrasyn (WP1130)是一种选择性deubiquitinase (DUB: USP5，UCH-L1，USP9x，USP14，和 UCH37)抑制剂，对Bcr/Abl也有抑制作用，也是一种JAK2传感器(不影响20S蛋白酶体)和转录激活剂(STAT)。Degrasyn (WP1130)可诱导凋亡而阻滞自噬。

Target	Value
DUB (Cell-free assay)
Bcr-Abl (Cell-free assay)	1.8 μM

除了诱导快速的Bcr/Abl下调而不影响Bcr或c-Abl，WP1130也会调节Jak2和c-Myc的稳定性，而不影响其他激酶(HER1，HER2，c-Kit，FAK，ERK1，ERK2，Akt，Btk，Src 和Src相关的激酶)或转录因子(野生型p53，STAT1，STAT3，STAT5，c-Jun，NF-κB，和Max)。不同于adaphostin 和Trisenox，WP1130在60分钟内诱导Bcr/Abl下调。与正常CD34在MM-1多发性骨髓瘤和其他肿瘤细胞系中，WP1130诱导快速的蛋白酶体依赖性c-Myc蛋白降解，与肿瘤生长的抑制相关。不同于AG490，WP1130作为一种部分选择性去泛素化酶(DUB)抑制剂，诱导快速显著的多泛素化(K48/K63连接)蛋白聚集到似核状聚集体，而不影响蛋白酶体活性。WP1130 (5 μM)直接抑制除UCH-L3外的USP9x，USP5，USP14，UCH-L1，和UCH37的DUB活性，导致抗细胞凋亡的下调和促细胞凋亡蛋白质，比如MCL-1和p53的增加。

WP1130给药抑制移植到裸鼠体内的K562肿瘤，以及野生型Bcr/Abl 和T315I突变体Bcr/Abl表达的BaF/3细胞的生长。与c-Myc的下调一致，WP1130对裸鼠体内已建立的A375黑色素瘤表现出有效的抑制作用。