Increasing Effects of Interferons for Melanoma

必须为手术后的高危患者和转移性疾病确定消除黑色素瘤的新疗法。 干扰素 (IFN) 在两种临床环境中都具有治疗活性，但对黑色素瘤或其他恶性肿瘤的临床有效性机制的理解几乎没有扩展。 潜在的临床抗肿瘤作用必须是在转录水平上发生的有效且多效性的基因调节作用。利用寡核苷酸阵列分析，已鉴定出黑色素瘤细胞系中由 IFN 诱导的 100 多个基因。 在等摩尔基础上，IFN-β对这些基因的诱导程度显着高于IFN-α2。 基于干扰素在黑色素瘤中的抗肿瘤作用可能来自对肿瘤细胞的直接作用的假设，细胞凋亡（干扰素的一种尚未被研究的作用）是我们研究的重点。细胞凋亡的诱导与芯片研究相结合，导致蛋白质 TRAIL（TNF 相关细胞凋亡诱导配体）成为一种部分解释黑色素瘤细胞死亡的机制。 在敏感的黑色素瘤细胞系中，IFN-β（而非 IFN-α2）会诱导与 TRAIL 相关的 caspase 依赖性细胞凋亡。 抗性黑色素瘤细胞系的特征在于缺乏IFN-α2或IFN-β的增殖抑制或凋亡诱导以及缺乏TRAIL诱导。 数据进一步表明细胞凋亡诱导受到 TRAIL 激活 NFkappaB（核因子 kappa B）的负面影响。为了了解干扰素作为抗肿瘤细胞因子并使用黑色素瘤作为模型，我们的工作假设是，尚未确定的基因和功能机制对干扰素的抗肿瘤作用有重大贡献。 我们根据基因组大小进行的估计表明，仍有超过 500 个干扰素刺激基因 (ISG) 有待鉴定。 该提案的目标是：1) 通过评估敏感和耐药黑色素瘤来鉴定可能有助于介导细胞凋亡反应和对 IFN 的抵抗的新基因，2) 定义和确认新鉴定的 ISG、TRAIL 对 IFN 诱导的细胞凋亡的功能作用，3) 确定 NF-κB 或其他诱导的抗细胞凋亡途径如何影响 IFN 和 TRAIL 的作用，以及 4) 作为小鼠和小鼠细胞凋亡的有效诱导剂。 TRAIL 开展 IFN-β 的 II 期试验，以确定转移性黑色素瘤的疾病反应。 这些数据应有助于了解 IFN 对黑色素瘤以及其他肿瘤的影响，并有助于初步了解 TRAIL 的治疗潜力。

New therapies to eliminate melanoma must be identified both for the high-risk patient after surgery and for metastatic disease. Interferons (IFNs) have therapeutic activity in both clinical settings but little expansion has occurred in understanding of mechanisms underlying clinical effectiveness in melanoma -- or indeed other malignancies. Underlying clinical antitumor effects must be the potent and pleiotropic gene modulatory effects that occur at a transcriptional level. Utilizing oligonucleotide array analysis, over 100 genes that are induced by IFNs in a melanoma cell line have been identified. On an equimolar basis these genes are induced to a substantially greater extent by IFN-beta than by IFN-alpha2. Based upon the hypothesis that the antitumor effects of IFNs in melanoma may result from direct effects on tumor cells, apoptosis, an understudied effect of IFNs, is a focus of our studies. Induction of apoptosis, coupled with array studies, led to the protein TRAIL (TNF-Related Apoptosis Inducing Ligand) as a mechanism that in part accounts for melanoma cell death. In sensitive melanoma cell lines, IFN-beta, but not IFN-alpha2, induces caspase dependent apoptosis that was associated with TRAIL. Resistant melanoma cell lines are characterized by lack of proliferative inhibition or apoptosis induction by either IFN- alpha2 or IFN-beta and lack of TRAIL induction. The data further suggest that apoptosis induction is negatively influenced by NFkappaB (Nuclear Factor kappa B) activation by TRAIL. With a goal of understanding of IFNs as antitumor cytokines and using melanoma as a model, our working hypothesis is that genes and functional mechanisms, yet to be identified, contribute substantially to the antitumor effects of IFNs. Our estimates based upon genome size suggest that greater than 500 interferon- stimulated genes (ISGs) remain to be identified. The goals of the proposal are: 1) By assessment of sensitive and resistant melanomas to identify new genes that may contribute to mediating apoptosis response and resistance in response to IFNs, 2) To define and confirm functional effects of the newly identified ISG, TRAIL, on IFN-induced apoptosis, 3) To determine how NF- kappaB or other induced anti-apoptotic pathways influence actions of IFNs and TRAIL, and 4) As an effective inducer of of apoptosis in mice and of TRAIL, to conduct a Phase II trial of IFN-beta to identify disease response in metastatic melanoma. The data should contribute to understanding of IFNs effects in melanoma but also other neoplasms and to a beginning understanding of the therapeutic potential of TRAIL.