RA-9 is a potent and selective proteasome-associated inhibitor of deubiquitinating enzymes (DUBs), with favorable toxicity profile and anticancer activity. RA-9 selectively induces apoptosis in ovarian cancer cell lines.

RA-9作为蛋白酶体相关DUBs的小分子抑制剂的特性描述。RA-9的处理在卵巢癌细胞系及来自捐献者的原代培养中选择性诱导凋亡的发生。RA-9曝光后细胞活性丧失，与折叠蛋白应答作为应对不可持续的蛋白质毒性压力的机制相关。

在体内治疗中，RA-9延缓了肿瘤生长，提高了总体生存率，并且被宿主良好地耐受。

Mice were inoculated i.p. with 100,000 ES-2 cells (in 100 μl DMEM) stably expressing GFP.?When tumor was detectable (approx.?6 days post inoculation), mice were randomly assigned into two groups receiving RA-9 or 0.9% saline.?Treatment with RA-9 was given i.p. on a one-day on, two-days off schedule.?The control group received the vehicle alone at the same schedule.?Working concentrations of RA-9 (10 mg/ml) were reached by dissolution in Cremophor EL and polyethylene glycol 400 (Sigma).?Prior to each injection RA-9 was further diluted in 0.9% saline (working concentration 1mg/ml).?To monitor for tumor growth, RA-9 treated and control mice were imaged with an IVIS SpectrumCT Pre-clinical in vivo imaging system (PerkinElmer) every other day.?Animals were sacrificed when abdomens became distended to twice normal size.