MOLECULAR ANALYSIS OF HEPATOMA CELL MIGRATION FACTOR

细胞运动是肿瘤细胞侵袭周围环境所必需的 组织，并实现转移。促进细胞生长的可溶性因子 这一过程中牵涉到了运动性。我们发现了一项活动 在刺激人成纤维细胞运动的条件培养液中 肝癌细胞。这项建议的长期目标是 描述这一新的因子，暂定为“肝癌细胞” 迁移系数“(HMF)。 HMF分散紧密排列的高分化肝癌菌落 细胞转化为单个细胞，并促进细胞向外迁移 殖民地。分散的细胞广泛分布，并假定 成纤维细胞，去分化形态。这些表型变化 用低于1 ng/ml的部分纯化的HMF诱导。这个 估计分子量(60 KDa)，靶细胞的狭窄范围 对肝细胞/肝癌细胞的特异性，以及其他生物学和 生化数据表明，HMF与其他运动因子不同 以及已知的影响细胞形态和运动的细胞因子。因此，我们的 工作假设是HMF是一种新的细胞因子类型的分子，它 调节肝细胞/肝癌细胞的迁移和分化 可能与体内肝癌的侵袭和转移有关。 为了研究HMF的生物学作用，我们将1)纯化HMF并获得 ITS氨基酸序列；2)分子克隆和测序；3) 用免疫组织化学方法研究HMF的组织分布 用特定的抗体探针染色；以及4)表征 HMF在分化、迁移和侵袭中的生物学作用 外源添加HMF和外源基因联合应用于肝细胞/肝癌细胞的研究 将hmf基因转移到细胞内。这些研究将有助于我们的 对肿瘤侵袭转移分子机制的认识 并明确了HMF在这些过程中的作用。

Cell locomotion is essential for tumor cells to invade into surrounding tissues and achieve metastasis. Soluble factors that enhance cellular motility have been implicated in the process. We have found an activity in conditioned media of human fibroblasts that stimulates the motility of hepatoma cells. The long-term objective of this proposal is to characterize this novel factor, tentatively termed "hepatoma cell migration factor" (HMF). HMF disperses tightly packed colonies of well-differentiated hepatoma cells into single cells and promotes the migration of the cells out of colonies. The dispersed cells spread extensively and assume a fibroblastic, dedifferentiated morphology. These phenotypical changes are induced with less than 1 ng/ml of partially purified HMF. The estimated molecular weight (60 kDa), the narrow range of target cell specificity toward hepatocytes/hepatoma cells, and other biological and biochemical data suggest that HMF is distinct from other motility factors and cytokines known to affect cell morphology and motility. Thus, our working hypothesis is that HMF is a novel cytokine-type molecule which regulates the migration and differentiation of hepatocytes/hepatoma cells and possibly the invasion and metastasis of hepatoma in vivo. To examine the biological roles of HMF, we will 1) purify HMF and obtain its amino acid sequences; 2) molecularly clone and sequence HMF cDNA; 3) investigate the tissue distribution of HMF by immunohistochemical staining with specific antibody probes; and 4) characterize the biological effects of HMF on the differentiation, migration and invasion of hepatocytes/hepatoma cells by using exogenously added HMF and by gene transfer of HMF cDNA into cells. These studies will contribute to our understanding of the molecular mechanisms of the invasion and metastasis of hepatoma in vivo and define a role for HMF in these processes.