Therapy of Melanoma with Bortezomib and Interferon-alpha

描述(由申请人提供)：使用Bortezomib和干扰素-α免疫疗法治疗黑色素瘤对细胞毒治疗的抵抗是恶性黑色素瘤的一个标志。目前治疗转移性疾病的标准是单剂达卡巴肼，其总体应答率仅为15%。因此，必须探索具有新作用机制的新制剂。Bortezomib(VELCADE，前身为PS-341)是一种新型的抗肿瘤化合物，是26S蛋白酶体的特异性和选择性抑制剂，26S蛋白酶体是细胞蛋白质降解的泛素-蛋白酶体途径的中心成分。Bortezomib治疗恶性细胞可通过多种机制导致细胞生长停滞和细胞死亡，包括改变细胞周期蛋白的周转和阻断有利于生存的信号。我们注意到，在干扰素-α(干扰素-a)的存在下，Bortezomib诱导的黑色素瘤细胞的凋亡被协同增强，干扰素-a是一种本身具有独特的促凋亡作用的试剂。进一步分析表明，细胞凋亡与bcl2水平降低和caspase蛋白激活有关。在小鼠恶性黑色素瘤模型中，我们还证明，与单独使用任何一种药物相比，Bortezomib和干扰素-a联合治疗后，荷瘤小鼠的存活率显著提高(p=0.02)。我们也有初步数据表明，用Bortezomib预处理外周血单个核细胞可以延长Jak-STAT信号转导通路的激活时间，以响应干扰素-a。这是首次检测蛋白酶体抑制剂与细胞因子结合时的抗肿瘤效果的实验。我们现在建议对转移性恶性黑色素瘤患者进行一项由研究者发起的波特佐米和干扰素-a2b的临床试验。我们假设干扰素-a将促进晚期恶性黑色素瘤患者由硼替佐米诱导的肿瘤细胞凋亡。治疗前后将对肿瘤进行活检，以便进行相关的免疫组织化学染色。还将使用一种新的流式细胞仪分析方法，仔细分析干扰素-a在患者免疫细胞中诱导的信号通路。这些研究将有助于确定由Bortezomib和干扰素-a2b联合调控的特定的细胞凋亡和免疫刺激通路。

DESCRIPTION (provided by applicant): Immunotherapy of Melanoma with Bortezomib and Interferon-Alpha Resistance to cytotoxic therapy is a hallmark of malignant melanoma. The current standard of care for metastatic disease is single-agent dacarbazine which has an overall response rate of just 15%. New agents with new mechanisms of action must therefore be explored. Bortezomib (Velcade, formerly PS-341) is a novel anti-tumor compound that is a specific and selective inhibitor of the 26S proteasome, a central component of the ubiquitin-proteasome pathway for the degradation of cellular proteins. Treatment of malignant cells with bortezomib leads to growth arrest and apoptotic cell death via multiple mechanisms including altered turnover of cell cycle proteins and blockade of pro-survival signals. We noted that bortezomib-induced apoptosis of melanoma cells was synergistically enhanced in the presence of interferon-alpha (IFN-a), an agent that has unique pro-apoptotic effects of its own. Further analysis revealed that apoptosis was associated with reduced levels of bcl-2 and activation of caspase proteins. Using a murine model of malignant melanoma, we also demonstrated that the survival of tumor-bearing mice was significantly enhanced following treatment with the combination of bortezomib and IFN-a as compared to either agent alone (p = 0.02). We also have preliminary data to suggest that pre-treatment of peripheral blood mononuclear cells with bortezomib leads to prolonged activation of the Jak-STAT signal transduction pathway in response to IFN-a. These are the first experiments to examine the anti-tumor effects of a proteasome inhibitor when combined with a cytokine. We now propose to conduct an investigator-initiated clinical trial of bortezomib and IFN-a2b in patients with metastatic malignant melanoma. We hypothesize that IFN-a will enhance bortezomib-induced tumor cell apoptosis in patients with advanced malignant melanoma. Tumors will be biopsied before and after therapy in order that correlative immunohistochemical stains can be performed. A careful analysis of IFN-a-induced signaling pathways in patient immune cells will also be conducted using a novel flow cytometric assay. These studies will help to define the specific apoptotic and immunostimulatory pathways that are being modulated by the combination of bortezomib and IFN-a2b.