Fibroblast activation protein (FAP) is a cell-surface serine protease that acts on various hormones and extracellular matrix components. FAP is highly upregulated in a wide variety of cancers, and is often used as a marker for pro-tumorigenic stroma. It has also been proposed as a molecular target of cancer therapies, and, especially in recent years, a great deal of research has gone into design and testing of diverse FAP-targeted treatments. Yet despite this growing field of research, our knowledge of FAP's basic biology and functional roles in various cancers has lagged behind its use as a tumor-stromal marker. In this review, we summarize and analyze recent advances in understanding the functions of FAP in cancer, most notably its prognostic value in various tumor types, cellular effects on various cell types, and potential as a therapeutic target. We highlight outstanding questions in the field, the answers to which could shape preclinical and clinical studies of FAP.

中文翻译：

---

成纤维细胞激活蛋白在癌症中的促肿瘤作用：回到基础。

成纤维细胞激活蛋白（FAP）是一种细胞表面丝氨酸蛋白酶，作用于多种激素和细胞外基质成分。FAP 在多种癌症中高度上调，通常用作促肿瘤基质的标记物。它也被提议作为癌症治疗的分子靶标，尤其是近年来，大量研究已深入到各种 FAP 靶向治疗的设计和测试中。然而，尽管研究领域不断发展，我们对 FAP 的基本生物学和在各种癌症中的功能作用的了解仍然落后于其作为肿瘤基质标志物的用途。在这篇综述中，我们总结并分析了了解 FAP 在癌症中的功能的最新进展，最值得注意的是它在各种肿瘤类型中的预后价值、对各种细胞类型的细胞作用以及作为治疗靶点的潜力。我们重点介绍该领域的突出问题，这些问题的答案可能会影响 FAP 的临床前和临床研究。