肿瘤相关中性粒细胞出现在多种癌症中，并且通常被报道为对结果产生负面影响。肿瘤微环境中存在的转化生长因子β（TGF-β）据报道有助于将中性粒细胞倾斜为更具有促肿瘤表型的状态。然而，目前尚不清楚TGF-β对中性粒细胞信号传导和迁移的影响。我们试图表征TGF-β在原代人类中性粒细胞和中性粒细胞样细胞系HL-60中的信号传导，并确定其是否直接诱导中性粒细胞迁移。我们发现TGF-β1无法在转膜或盖培迁移实验中诱导中性粒细胞趋化。然而，TGF-β1以剂量和时间依赖的方式激活中性粒细胞中的经典SMAD3信号传导和非经典ERK1/2信号传导。此外，浸润性乳腺癌细胞所分泌的肿瘤条件培养基（TCM）中的TGF-β1导致SMAD3激活。我们发现TCM诱导中性粒细胞分泌白三烯B4（LTB4），后者是一种重要的脂质介质，能够扩大中性粒细胞的招募范围。然而，单独的TGF-β1不能诱导LTB4的分泌。RNA测序揭示了TGF-β1和TCM改变了HL-60细胞的基因表达，包括促肿瘤基因OSM（oncostatin M）和血管内皮生长因子A（VEGFA）的mRNA水平。对TGF-β1对中性粒细胞信号传导、迁移和基因表达的作用和影响的新认识，对了解肿瘤微环境中中性粒细胞的变化具有重要意义。 版权：© 2023 Hein等。本文为开放获取文章，根据创作共享许可证无限制使用、分发和再生产，只要保留原始作者和来源的署名。

Tumor-associated neutrophils are found in many types of cancer and are often reported to contribute to negative outcomes. The presence of transforming growth factor-beta (TGF-β) in the tumor microenvironment reportedly contributes to the skewing of neutrophils to a more pro-tumor phenotype. The effects of TGF-β on neutrophil signaling and migration are, however, unclear. We sought to characterize TGF-β signaling in both primary human neutrophils and the neutrophil-like cell line HL-60 and determine whether it directly induces neutrophil migration. We found that TGF-β1 does not induce neutrophil chemotaxis in transwell or underagarose migration assays. TGF-β1 does activate canonical signaling through SMAD3 and noncanonical signaling through ERK1/2 in neutrophils in a time- and dose-dependent manner. Additionally, TGF-β1 present in the tumor-conditioned media (TCM) of invasive breast cancer cells results in SMAD3 activation. We discovered that TCM induces neutrophils to secrete leukotriene B4 (LTB4), which is a lipid mediator important for amplifying the range of neutrophil recruitment. However, TGF-β1 alone does not induce secretion of LTB4. RNA-sequencing revealed that TGF-β1 and TCM alter gene expression in HL-60 cells, including the mRNA levels of the pro-tumor oncostatin M (OSM) and vascular endothelial growth factor A (VEGFA). These new insights into the role and impact of TGF-β1 on neutrophil signaling, migration, and gene expression have significant implications in the understanding of the changes in neutrophils that occur in the tumor microenvironment.Copyright: © 2023 Hein et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.