BACKGROUND The tumor microenvironment (TME) represents the many components occupying the space within and surrounding a tumor, including cells, signaling factors, extracellular matrix, and vasculature. Each component has the potential to assume many forms and functions which in turn contribute to the overall state of the TME, and further contribute to the progression and disposition of the tumor itself. The sum of these components can drive a tumor towards progression, keep a migratory tumor at bay, or even control chemotherapeutic response. The wide potential for interaction that the TME is an integral part of a tumor's ecosystem, and it is imperative to include it when studying and modeling cancer in vitro. Fortunately, the development of tissue engineering and biofabrication technologies and methodologies have allowed widespread inclusion of TME-based factors into in vitro tissue-equivalent models. METHODS In this review, we compiled contemporary literature sources to provide an overview of the field of TME models, ranging from simple to complex. RESULTS We have identified important components of the TME, how they can be included in in vitro study, and cover examples across a range of cancer types. CONCLUSION Our goal with this text is to provide a foundation for prospective research into the TME.

中文翻译：

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肿瘤类器官中肿瘤微环境的体外建模。

背景肿瘤微环境（TME）代表占据肿瘤内部和周围空间的许多成分，包括细胞、信号因子、细胞外基质和脉管系统。每个组件都有可能呈现多种形式和功能，进而影响 TME 的整体状态，并进一步促进肿瘤本身的进展和处置。这些成分的总和可以推动肿瘤进展，阻止迁移性肿瘤，甚至控制化疗反应。TME 具有广泛的相互作用潜力，是肿瘤生态系统不可或缺的一部分，在体外研究和建模癌症时必须将其包括在内。幸运的是，组织工程和生物制造技术和方法的发展使得基于 TME 的因素广泛纳入体外组织等效模型中。方法 在这篇综述中，我们汇编了当代文献资料，以概述从简单到复杂的 TME 模型领域。结果我们已经确定了 TME 的重要组成部分，如何将它们包括在体外研究中，并涵盖了一系列癌症类型的示例。结论 本文的目标是为 TME 的前瞻性研究奠定基础。结果我们已经确定了 TME 的重要组成部分，如何将它们包括在体外研究中，并涵盖了一系列癌症类型的示例。结论 本文的目标是为 TME 的前瞻性研究奠定基础。结果我们已经确定了 TME 的重要组成部分，如何将它们包括在体外研究中，并涵盖了一系列癌症类型的示例。结论 本文的目标是为 TME 的前瞻性研究奠定基础。