Multitargeted nanoparticles inhibit cancer invasion by disrupting cancer-associated fibroblast-tumor cell crosstalk and modulating collagen pattern and EMT

BACKGROUND: Cancer-associated fibroblasts (CAFs), a major component of tumor stroma, play an important role in tumor progression and metastasis via paracrine signaling, extracellular matrix (ECM) remodelling, and the secretion of growth factors, cytokines, and chemokines promoting tumor growth. In this study, we aim to develop a multitargeted nanoparticle formulation to simultaneously target CAFs and triple negative breast cancer (TNBC) cells, aiming to block their crosstalk, remodel the ECM, and inhibit epithelial-mesenchymal transition (EMT) to suppress tumor growth and metastatic processes. METHODS: The potential of CAFs as therapeutic target for TNBC was evaluated by analyzing RNA-seq data from TNBC patients. A novel iRGD-functionalized polymer-lipid hybrid nanoparticle (iRGD-DOX-oHA-PLN) was specifically designed to target αvβ3 and αvβ5 receptors on both tumor cells and CAFs. A murine TNBC cell line and its orthotopic in vivo model were used for efficacy evaluation. Within this model, a murine fibroblast cell line was incorporated as a source of CAFs for in vitro investigation of the crosstalk between CAFs and tumor cells. In addition, the mechanism of iRGD-DOX-oHA-PLN nanoparticles in disrupting CAF-tumor cell interactions by blocking downstream features associated with metastases including paracrine communication, collagen organization and epithelial-mesenchymal transition (EMT) associated with metastasis were investigated both in vitro and in vivo. RESULTS: The iRGD-DOX-oHA-PLN demonstrates higher cellular uptake and cytotoxicity in CAFs overexpressing integrins αvβ3 and αvβ5 compared to normal fibroblasts. The results demonstrate that iRGD-DOX-oHA-PLN significantly restricts the interaction of CAFs and cancer cells, due to interruption of paracrine communication induced by pro-metastatic TGF-β and CXCL12 secretion together with a reduction of CXCR4 expression. Consistent with the in vitro results, in an orthotopic syngeneic TNBC murine model, iRGD-DOX-oHA-PLN effectively depletes CAFs, reducing tumor-associated collagen production, and altering tumor-associated collagen signatures (TACS). Thus, iRGD-DOX-oHA-PLN treatment impedes tumor invasion by reducing MMP-9 secretion and inhibiting EMT. CONCLUSION: The data reveals that simultaneously targeting CAFs and tumor cells, while blocking their crosstalk via application of a multitargeted nanomedicine, offers a compelling and effective strategy to inhibit metastasis of TNBC.