TUMOR HOST INTERACTIONS IN HUMAN MELANOMA METASTASIS

背景：人们对负增长损失的性质知之甚少 在人类皮肤黑色素瘤的背景下控制，以及这种损失如何 可能影响疾病的发展和恶性进展。在 在本赠款期内进行的研究获得了证据， 负增长控制的三个重要方面 (and其颠覆）。它们是：（i）成纤维细胞或 内皮衍生的（即，旁分泌）白细胞介素-6（IL-6）可以在 体外作为黑色素瘤细胞系的有效生长抑制剂， 早期可治愈的原发性病变，而来自更多的细胞系 晚期的、具有转移能力的病变对此具有抗性， 抑制作用;（ii）在一个重要的子集（50-70%）的晚期 在黑色素瘤细胞系中，IL-6似乎被打开并作为一种免疫调节剂发挥作用。 体外促有丝分裂自分泌生长因子-我们称之为 “细胞因子转换”;（iii）许多其它细胞因子（IL-1，TGF-β， TNF-α和制瘤素M）也可以在体外作为生长因子发挥作用。 抑制剂的早期阶段黑色素瘤，而这种影响是减少或 随着肿瘤的进展而完全消失-我们称这种现象为 “多细胞因子抵抗”。 问题：所有上述结果都是在体外获得的 使用已建立的黑色素瘤细胞系。接下来的逻辑阶段 研究的目的是探讨这些在体外的意义 对人体实验和临床体内行为的研究结果 黑色素瘤和相关的分子机制。 总体指导假设和具体目的：假设IL-6 耐药本身、一般的多细胞因子耐药和IL-6-细胞因子 “转换”有助于人类黑素瘤的恶性侵袭性。 具体目标是：（i）评价旁分泌能力和/或 自分泌IL-6以改变体内人黑素瘤的生长（即， 裸鼠），并最终作为生长刺激剂;（ii）评估 人黑色素瘤组织中IL-6 mRNA和蛋白相对表达 样本（在疾病的不同阶段），并作为可能的预后 黑色素瘤侵袭性的指标;（iii）确定黑色素瘤侵袭性的分子生物学指标。 IL-6信号转导改变的特征 黑素瘤细胞中的IL-6抗性。 重要性：拟议的实验对于以下方面具有重要意义： 若干问题包括：（一）帮助揭示 人皮肤黑色素瘤的进展和发病机制，以及，（ii） 阐明了“造血”细胞因子和阴性（丧失） 黑色素瘤病理生物学中的生长控制。 尽管我们的实验 只有人类黑色素瘤，它们可能具有更广泛的相关性，因为它是 现在已知多种人类癌产生IL-6， 其临床意义在很大程度上是未知的。

Background: Little is known about the nature of loss of negative growth controls in the context of human cutaneous melanoma, and how such losses may affect the development and malignant progression of the disease. In studies undertaken during the current grant period evidence was obtained for what may be three new important aspects of negative growth control (and its subversion) in human melanoma. These are: (i) fibroblast or endothelial derived (ie. paracrine) interleukin-6 (IL-6) can function in vitro as a potent growth inhibitor of melanoma cell lines established from early-stage curable primary lesions, whereas cell lines from more advanced, metastatically-competent, lesions are resistant to this inhibitory effect; (ii) in a significant subset (50-70%) of advanced-stage melanoma cell lines, IL-6 appears to be switched on and function as a mitogenic autocrine growth factor in vitro - a process we have termed "cytokine switching"; (iii) a number of other cytokines (IL-1, TGF-beta, TNF-alpha and oncostatin M) can also function in vitro as growth inhibitors for early-stage melanomas, whereas this effect is diminished or lost altogether with tumor progression - a phenomenon we have termed "multicytokine resistance". The Problem: All of the aforementioned results were obtained in vitro using established melanoma cell lines. The next logical phases of investigation are to investigate the significance of these in vitro findings to the experimental and clinical in vivo behavior of human melanomas, and the molecular mechanisms involved. Overall Guiding Hypothesis and Specific Aims: It is hypothesized that IL-6 resistance per se, multicytokine resistance in general, and IL-6 "cytokine switching" contribute to the malignant aggressiveness of human melanoma. The specific aims are: (i) to evaluate she capacity of paracrine and/or autocrine IL-6 to alter the growth of human melanomas in vivo (i.e. in nude mice), and ultimately to act as a growth stimulant; (ii) to evaluate the relative expression of IL-6 mRNA and protein in human melanoma tissue samples (at different stages of disease), and as possible prognostic indicators of melanoma aggressiveness; (iii) to determine the molecular characteristics of IL-6 signal transduction alterations responsible for IL-6 resistance in melanoma cells. Significance: The proposed experiments are significant in relation to several issues including: (i) helping to uncover part of the basis for the progression and pathogenesis of human cutaneous melanomas and, (ii) elucidating the role of "hemopoietic" cytokines and (loss of) negative growth controls in melanoma pathobiology. Although our experiments deal only with human melanoma they may have much broader relevance since it is now known that a diverse array of human carcinomas produce IL-6, the clinical significance of which is largely unknown.