传统观念认为癌症的进展仅仅是由癌细胞基因和表型变化的多个过程所致。但最近20年的研究显示肿瘤微环境(tumor microenvironment，TME)对于肿瘤行为的影响是同等重要的。TME的组成包括局部的基质细胞，如定植的成纤维细胞(cancer-associated fibroblasts，CAF)和巨噬细胞，远处招募的细胞如内皮细胞、免疫细胞包括髓系和淋巴系细胞、骨髓来源的前体细胞和循环中的血小板。TME能够分泌影响并调控肿瘤表型的分子，如能揭示成瘤细胞与微环境之间的关系，必定能够为肿瘤的发生发展及治疗等一系列难题提供全新的视角。
Stromal cells of the tumor microenvironment in tumor metastasis
Generally, it was believed that tumor progression was caused by a multistep process with genetic and epigenetic changes targeting only tumor cells. However, over the past two decades, the tumor microenvironment (TME) proved to play an equally important role in developing and establishing the morphology, growth and invasiveness of a malignancy. The TME includes local stromal cells, such as resident fibroblasts and macrophages, as well as distinct recruited cells such as endothedial cells, immune cells. Cancer-associated fobroblasts interact with tumor cells and additional components of the stroma, and once activated can induce vascular permeability and angiogenesis. Tumor-associated macrophages and tumor-associated neutrophils can exert protumoral functions, while inhibiting the antitumoral immune surveillance. Since the TME plays a key role in developing and establishing the morphology, growth and invasiveness, revealing the relationship between them might promote innovative treatments that make controlling metastasis possible.