# Patient-Derived Procoagulant Breast Fibroblasts Expressing Tissue Factor Promote Breast Cancer Cell Migration

## TL;DR

This study shows that fibroblasts in breast tissue, even those far from tumors, can take on a procoagulant state that helps cancer cells move and spread.

## Contribution

The study reveals that distant fibroblasts can adopt a cancer-associated, procoagulant phenotype and that tissue factor inhibition reduces breast cancer cell migration.

## Key findings

- Fibroblasts from distant breast tissue show CAF-like and procoagulant traits similar to tumor-associated fibroblasts.
- Inhibiting tissue factor from fibroblasts significantly reduces MCF-7 breast cancer cell migration.
- Combined inhibition of tissue factor and TGFβ1 further suppresses cancer cell migration.

## Abstract

Cancer-associated fibroblasts (CAFs) play a key role in breast cancer progression and exhibit a procoagulant phenotype within the tumour microenvironment (TME). We hypothesised that this procoagulant phenotype correlates with a CAF-like phenotype and that fibroblasts distant from the immediate TME are less procoagulant. We also proposed that the procoagulant phenotype contributes functionally to breast cancer progression.

Primary fibroblasts were cultured from human breast tumour tissue and matched normal breast tissue from regions distant to the tumour. Conditioned media (CM) from these cells were collected for analysis. We conducted immunocytochemistry, western blotting, transforming growth factor beta 1 (TGFβ1) ELISA, tissue factor (TF) activity and procoagulant activity assays. A positive correlation was found between the expression of TF and alpha-smooth muscle actin (α-SMA), a CAF marker, and between fibroblast procoagulant activity and secretion of the CAF inducer, TGFβ1.

Interestingly, fibroblasts from distant breast tissue exhibited CAF-like and procoagulant phenotypes similar to tumour-associated fibroblasts. To assess functional relevance, scratch wound migration assays were performed using MCF-7 breast cancer cells. Inhibition of TF derived from both tumour and distant fibroblasts significantly reduced MCF-7 cell migration. Combined inhibition of TF and TGFβ1 in distant fibroblast CM further suppressed migration.

These findings suggest that tumour-derived influences may extend beyond the immediate TME, inducing a CAF-like, procoagulant phenotype in fibroblasts from histologically normal breast tissue. Furthermore, fibroblast-derived TF promotes breast cancer cell migration which is important for the processes of invasion and metastasis. This further highlights TF as a promising therapeutic target in breast cancer.

Procoagulant fibroblasts in the breast tumour microenvironment promote breast cancer cell migration through the TF-FVIIa-FXa-PAR2 signalling pathway (Ogunlayi, H, https://biorender.com/i3md663 (2025)).

Procoagulant fibroblasts in the breast tumour microenvironment promote breast cancer cell migration through the TF-FVIIa-FXa-PAR2 signalling pathway (Ogunlayi, H, https://biorender.com/i3md663 (2025)).

The online version contains supplementary material available at 10.1007/s10911-026-09596-w.