Extracellular Vesicles from M1-Polarized Macrophages Combined with Hyaluronic Acid and a β-Blocker Potentiate Doxorubicin’s Antitumor Activity by Downregulating Tumor-Associated Macrophages in Breast Cancer

Abstract

One of the main reasons for cancer’s low clinical response to chemotherapeutics is the highly immunosuppressive tumor microenvironment (TME). Tumor-ass ociated M2 macrophages (M2-TAMs) orchestrate the immunosuppression, which favors tumor progression. Extracellular vesicles (EVs) have shown great potential for targeted therapies as, depending on their biological origin, they can present different therapeutic properties, such as enhanced accumulation in the target tissue or modulation of the immune system. In the current study, EVs were isolated from M1-macrophages (M1-EVs) pre-treated with hyaluronic acid (HA) and the β-blocker carvedilol (CV). The resulting modulated-M1 EVs (MM1-EVs) were further loaded with doxorubicin (MM1-DOX) to assess their effect in a mouse model of metastatic tumor growth. The cell death and cell migration profile were evaluated in vitro in 4T1 cells. The polarization of the RAW 264.7 murine macrophage cell line was also analyzed to evaluate the effects on the TME. Tumors were investigated by qRT-PCR and immunohistochemistry. MM1-DOX reduced the primary tumor size and metastases. NF-κB was the major gene downregulated by MM1-DOX. Furthermore, MM1-DOX reduced the expression of M2-TAM (CD-163) in tumors, which resulted in increased apoptosis (FADD) as well as decreased expression of MMP-2 and TGF-β. These results suggest a direct effect in tumors and an upregulation in the TME immunomodulation, which corroborate with our in vitro data that showed increased apoptosis, modulation of macrophage polarization, and reduced cell migration after treatment with M1-EVs combined with HA and CV. Our results indicate that the M1-EVs enhanced the antitumor effects of DOX, especially if combined with HA and CV in an animal model of metastatic cancer.

WITHDRAWN: Effect of Ruai-Sanyin formula maintenance therapy after completion of standard adjuvant treatment on survival in women with early-stage triple negative breast cancer: A multicenter prospective cohort study

“…In ammation has been demonstrated to be closely related to all stages of development and malignant progression of TNBC [33] . Once in ammatory tumor microenvironment (TME) is established, in ammatory factors from tumor cells or interstitial cells would induce breast cancer cells proliferation by initially activating oncogenes and subsequently inactivating tumor suppressor genes [34][35] . It follows that controlling in ammation appears to be an important approach to a more effective anticancer treatment [36] .…”

Extracellular vesicles in the treatment and diagnosis of breast cancer: a status update

“…In addition, breast cancer cells have been found to deliberately deviate trajectories during migration with the help of EVs and hyaluronic acid. This explains the role of EVs and hyaluronic acid in guiding the migration and metastasis of tumor cells (16). A study by Eckhard et al confirmed the role of exosomal Rab27a in breast cancer development and metastasis, which indicated that targeting Rab27a reduced the release of exosomes, thus retarding breast cancer growth (17).…”

Macrophage-Derived Extracellular Vesicles: A Promising Tool for Personalized Cancer Therapy

“…Macrophage-derived EVs, acting as cellular mediators, affect the polarization of TAMs. For this reason, EVs derived from M1-like macrophages were recently investigated to obtain an in situ M2 to M1 repolarization [ 134 ]. It is noteworthy that Wang et al focused their attention on the different pathways’ activation by investigating EVs derived from M1-like or M2-like macrophages, in order to evaluate the different effect of natural cargo in these nanovesicles based on parent cells’ polarization [ 132 ].…”