Neutrophil Extracellular Traps (NETs) Promote Pro-Metastatic Phenotype in Human Breast Cancer Cells through Epithelial–Mesenchymal Transition

Abstract

Neutrophil extracellular traps (NETs) have been associated with several steps of tumor progression, including primary growth and metastasis. One of the key features for the acquisition of the metastatic ability is the epithelial–mesenchymal transition (EMT), a complex cellular program. In this study, we evaluated the ability of isolated NETs in modulating the pro-metastatic phenotype of human breast cancer cells. Tumor cells were treated with isolated NETs and then samples were generated for cell migration, quantitative RT-PCR, western blotting, immunofluorescence, and flow cytometry assays. RNA-seq data from The Cancer Genome Atlas (TCGA) database were assessed. NETs changed the typical epithelial morphology of MCF7 cells into a mesenchymal phenotype, a process that was accompanied by enhanced migratory properties. Additional EMT traits were observed: increased expression of N-cadherin and fibronectin, while the E-cadherin expression was repressed. Notably, NETs positively regulated the gene expression of several factors linked to the pro-inflammatory and pro-metastatic properties. Analyses of TCGA data showed that samples from breast cancer patients exhibit a significant correlation between pro-tumoral and neutrophil signature gene expression, including several EMT and pro-metastatic factors. Therefore, NETs drive pro-metastatic phenotype in human breast cancer cells through the activation of the EMT program.

Neutrophil extracellular DNA traps promote pancreatic cancer cells migration and invasion by activating EGFR/ERK pathway

“…Next, we examined the mechanism by which NETs could activate the EGFR pathway. It has been shown that various kinds of cytokines are secreted in the formation of NETs which maybe induce the invasive and migratory abilities of pancreatic cancer cells, such as IL‐6, IL‐1β, IL‐1A, IL‐7A, IL‐17A, IL‐4, IL‐11, IL‐33, IL‐17F, IL‐37, TGF‐α TNF, IL‐23, IL‐10, IL‐36, IL‐29 and IL‐14 16,36‐40 . Real‐time PCR results showed that IL‐1β, IL‐6, IL‐8, IL‐10 and IL‐36 mRNA levels were significantly upregulated in NETs and downregulated when the formation of NETs was inhibited (Figure 5A).…”

“…NETs also act as a drug target to counteract chronic and acute inflammation 15 . It has also been reported that NETs could promote EMT 16 and enhance metastasis through CCDC25 17 in breast cancer.…”

The Crosstalk Between Cancer Cells and Neutrophils Enhances Hepatocellular Carcinoma Metastasis via Neutrophil Extracellular Traps-Associated Cathepsin G Component: A Potential Therapeutic Target

“…We hypothesized that a likely target for proteases is the adhesion molecule expressed on the surface of HCC cells. 31 , 41 , 43 In order to test this hypothesis, HCC cell layers were incubated with NETs-CM for up to 20 h; then, the depleted area of HCC cells was quantified. We observed that incubation with NETs-CM resulted in significant dyshesion of the HCC cell layers ( Figure 9C ).…”

Neutrophil extracellular traps induce the epithelial-mesenchymal transition: implications in post-COVID-19 fibrosis

“…Since NETosis is toxic in the lung (4, 6) and it induces the EMT in breast cancer cells (9), we investigated if NETs can induce the EMT in the alveolar epithelial cell line A549. We used PMA as a primary chemical effector of NETosis.…”

“…The direct consequence of NETs persistence in the lung is the damage of epithelial and endothelial cells, driven predominantly by histones (1). Additionally, NETs have been found to drive the EMT in the context of the breast cancer thanks to their capacity to upregulate transcription factors involved in the EMT (ZEB1 and SNAI1) (9). Given these premises, the aim of this study is to assess whether NETosis may drive the EMT also in lung epithelial cells.…”