Department of Laboratory Medicine, The First Affiliated Hospital of Xi'an Medical University, Xi'an, China.
Department of Cellular and Organ Pathology, Graduate School of Medicine, Akita University, Akita, Japan.
Histol Histopathol. 2022 Dec;37(12):1167-1175. doi: 10.14670/HH-18-474. Epub 2022 May 31.
Lung cancer is a high-risk tumor and is a main cause of death worldwide. The tumor aggressiveness and degree of malignancy depend not only on the tumor itself, but also on the microenvironment. The inflammatory microenvironment is one of the key factors in promoting the progression of lung cancer. It has been found that macrophages are the most abundant immune cells in the tumor microenvironment, with strong plasticity and heterogeneity. Tumor-Associated Macrophages (TAMs) are important components of the tumor immune microenvironment. TAMs are thought to be polarized into two main phenotypes: inflammatory or classically activated (M1) and antiinflammatory or alternatively activated (M2) macrophages. Their phenotype and function change according to environment and the appearance of tumor cells. M2 macrophages have been reported to be protumorigenic, because they can promote the formation of blood vessels in the tumor microenvironment, helping tumor cells escape the body's immune defense and promote their growth, by releasing a variety of cytokines, including chemokines, inflammatory factors and growth factor. However, the prognostic impact of TAMs and their phenotypes in non-small-cell lung cancer (NSCLC) remains to be fully elucidated. Some reports of the association between the characteristics of macrophages in lung tumor and patients' survival outcomes show contradicting results. In order to explore the prognostic role of TAMs in NSCLS, the association between the phenotype, density and distribution of macrophages and the prognosis of human NSCLC, as well as the potential mechanisms of M2 macrophages leading to poor prognosis in NSCLC, are reviewed in this study.
肺癌是一种高危肿瘤，是全球范围内主要的死亡原因之一。肿瘤的侵袭性和恶性程度不仅取决于肿瘤本身，还取决于微环境。炎症微环境是促进肺癌进展的关键因素之一。已经发现，巨噬细胞是肿瘤微环境中最丰富的免疫细胞，具有很强的可塑性和异质性。肿瘤相关巨噬细胞（TAMs）是肿瘤免疫微环境的重要组成部分。TAMs 被认为可极化为两种主要表型：炎症型或经典激活（M1）和抗炎型或替代激活（M2）巨噬细胞。它们的表型和功能根据环境和肿瘤细胞的出现而变化。据报道，M2 巨噬细胞具有致瘤性，因为它们可以通过释放多种细胞因子，包括趋化因子、炎症因子和生长因子，促进肿瘤微环境中血管的形成，帮助肿瘤细胞逃避机体的免疫防御并促进其生长。然而，TAMs 及其表型在非小细胞肺癌（NSCLC）中的预后影响仍有待充分阐明。一些关于肺肿瘤中巨噬细胞特征与患者生存结局之间关联的报告显示出相互矛盾的结果。为了探讨 TAMs 在 NSCLS 中的预后作用，本研究综述了巨噬细胞的表型、密度和分布与人类 NSCLC 预后的关系，以及 M2 巨噬细胞导致 NSCLC 预后不良的潜在机制。
