Tumor-activated neutrophils promote metastasis in breast cancer via the G-CSF-RLN2-MMP-9 axis

Abstract

The immune component of the tumor microenvironment is essential for the regulation of cancer progression. In breast cancer (BC), a patient’s tumor mass is frequently infiltrated by neutrophils (tumor-associated neutrophils, TANs). Our study addressed the role of TANs and their mechanism of action in BC. Using quantitative IHC, ROC, and Cox analysis, we demonstrated that a high density of TANs infiltrating the tumor parenchyma was predictive of poor prognosis and of decreased progression-free survival of patients with BC, who underwent surgical tumor removal without previous neoadjuvant chemotherapy, in three different cohorts: training, validation, and independent cohorts. Conditioned medium from human BC cell lines prolonged the life span of healthy donor neutrophils ex vivo. Neutrophils activated by the supernatants of BC lines demonstrated an increased ability to stimulate proliferation, migration, and invasive activity of BC cells. Cytokines involved in this process were identified using antibody arrays. The relationship between these cytokines and the density of TANs was validated by ELISA and IHC in fresh BC surgical samples. It was determined that tumor-derived G-CSF significantly extended the lifespan and increased the metastasis-promoting activities of neutrophils via the PI3K-AKT and NF-κB pathways. Simultaneously, TAN-derived RLN2 promoted the migratory abilities of MCF7cells via PI3K-AKT-MMP-9. Analysis of tumor tissues from 20 patients with BC identified a positive correlation between the density of TANs and the activation of the G-CSF-RLN2-MMP-9 axis. Finally, our data demonstrated that TANs in human BC have detrimental effects, supporting malignant cell invasion and migration.

Tumor-associated neutrophils are a negative prognostic factor in luminal breast cancers lacking immunosuppressive macrophage recruitment

“…The results of our work suggest that increased CD66b+ cell density both in the stromal and intraepithelial compartment of central tumor tissue from early luminal breast cancers is a negative predictive factor associated with tumor progression. This is consistent with the above-mentioned results of studies in other subtypes of breast cancer [27,28,30,31]. In addition, we also made intriguing novel observations in tissue beyond the primary tumor: Although there was limited availability of normal tissue samples in this study, a negative prognostic relevance of CD66b+ cells was also observed in these samples.…”

“…In hepatocellular cancer, Zhou et al reported the recruitment of tumor-associated macrophages by TANs as a mechanism of tumor progression [36]. Tumor-induced G-CSF release, which as described by Sheng et al promotes metastasis in TANs via the G-CSF-RLN2-MMP-9 axis, also affects the polarization of TAMs to the immunosuppressive M2-like phenotype [31].…”

Prognostic Significance of Cytotoxic-T-Lymphocytes to Immunosuppressive Cells Ratio (CIL) in Laryngeal Squamous Cell Carcinoma

“…N2 neutrophils are characterized by overexpression of VEGF and CXCR4, promoting tumor proliferation by facilitating tumor angiogenesis, invasion, and metastasis (21) . Both M2 macrophages and N2 neutrophils have been reported to exhibit negative predictive value for patient survival outcomes (22)(23)(24)(25).…”

The dual role of autophagy in the regulation of cancer treatment

“…Previous studies have demonstrated that immune cells infiltrating tumors can be influenced by interactions in the tumor microenvironment to support tumor progression (Kwantwi 2023b , 2023c ; Sheng et al 2023 ; Peng et al 2021 ; Cai et al 2020 ; Kwantwi et al 2021a ; Li et al 2021 ). Notably, autophagy induction can shape immune cells to gain protumor functions leading to therapeutic resistance and tumor progression (Bustos et al 2020 ; Ishimwe et al 2020 ; Jiang et al 2019 ; Janji et al 2018 ).…”