Analysis of Intratumoral Crosstalk in Clonal Populations of OvarianTumor Cells

描述（由申请人提供）：控制癌症最重要的挑战之一是个体肿瘤肿瘤细胞的高度异质性。虽然肿瘤细胞的异质性已经在许多层面上被描述，并且对产生异质性的过程的理解正在出现，但对肿瘤细胞的异质性亚群在其功能活动中的差异程度以及亚群之间的相互作用是否影响肿瘤的发生和进展知之甚少。研究这些问题的主要障碍是缺乏在培养中保持人类肿瘤异质性和从单个肿瘤中繁殖不同克隆亚群的方法。与我们的合作者一起，我们已经开发了克服这些障碍的方法，使分离、培养和表征卵巢肿瘤细胞的克隆群体成为可能，然后在移植克隆混合物产生的肿瘤异种移植物中跟踪条形码，表位标记的克隆群体。在一项初步研究中使用这些方法，我们获得了克隆间合作的证据

DESCRIPTION (provided by applicant): One of the most significant challenges in controlling cancer is the high degree of heterogeneity within the neoplastic cells of individual tumors. While tumor cell heterogeneity has been described at many levels and an understanding of the processes that create heterogeneity is emerging, the extent to which the heterogeneous subpopulations of tumor cells vary in their functional activities and whether interactions between subpopulation influence tumor initiation and progression is poorly understood. Major barriers to investigating these questions have been the lack of methodologies to maintain the heterogeneity of human tumors in culture and to propagate distinct clonal subpopulations from individual tumors. Together with our collaborators, we have developed methodologies that overcome these barriers and make it feasible to isolate, culture, and characterize clonal populations of ovarian tumor cells and then track barcoded, epitope-tagged clonal populations within tumor xenografts generated from mixtures of transplanted clones. Using these approaches in a pilot study, we obtained evidence for interclonal collaborations that significantly affect tumor progression - most interestingly, we found that clonal populations of cancer cells which are unable to initiate tumor formation on their own, can strongly promote the expansion of primary tumors and metastasis at specific organ sites when mixed with 'tumor-initiating' clones. This supports the hypothesis that clonal subpopulations within a tumor cooperate with one another to promote tumor expansion and metastasis. In this proposal, we describe plans to use a systematic approach to test this hypothesis in human ovarian tumors by (1) isolating and characterizing the extent of genetic and phenotypic variation among a large set of clonal populations derived from ovarian tumors, (2) comparing the activities of single clonal populations to mixtures of such populations in order to investigate the existence and nature of intratumoral cross talk, (3) tracking intratumoral localization of clonal populations over time, an (4) elucidating the mechanisms responsible for phenotypes generated by intratumoral crosstalk.