ACD47-modified Paclitaxel Immunoliopsomes For The Treatment Of Triple-negative Breast Cancer Study

Purpose:Triple negative breast cancer(TNBC),a specific breast cancer,is negative for estrogen receptor,progesterone receptor and human epidermal growth receptor-2.And TNBC is characterized by a high recurrence rate,poor effect and poor prognosis.Therefore,a novel strategy was designed to improve the treatment of TNBC.Methods:In the face of tumour disease,the concept of chinese medicine treatment is not to"remove the tumour",but to focus on the whole body of the tumour patient based on the idea of"holistic"and"supporting the righteous and dispelling the evil",in order to achieve the purpose of body’s health.In this study,inspired by the abundance of innate immune cell type tumor-associated macrophages(TAMs)in TNBC,we propose a matrix metalloproteinase 2(MMP2)-responsive’holistic’therapeutic strategy for the co-delivery of PTX and anti-CD47(aCD47)through MMP2-responsive immune liposomes(ILips).Results:First,we characterized the basic properties of immunoliposomes,the enzyme-responsive drug-loaded immune liposomes(i.e.PTX-ILips)have a particle size of around120 nm,a potential of around-30 m V and a spherical vesicle structure.The cumulative release of aCD47 was significantly increased in the presence of MMP2 enzyme.These results demonstrate our success in preparing aCD47-modified paclitaxel-immune liposomes that have a fundamental nano advantage and are characterised by a good enzymatic response.At the in vitro cellular level,we evaluated the morphology and phagocytosis of treated macrophages,and test anti-tumour activity.The morphology of macrophages changed to a round-like shape after ILips treatment;the expression of the cell surface receptor CD80increased while that of CD206 decreased;phagocytosis of foreign bodies(microspheres)was significantly increased;in the co-culture system of M2 macrophages and TNBC tumor cells MDA-MB-231,an increase in IL-6 and TNF-αlevels were increased and IL-10 and TGF-βlevels were decreased.In the in vitro anti-tumor level,both M2macrophages and MDA-MB-231 showed high uptake of ILips;PTX-ILips could inhibit the migration ability of MDA-MB-231 up to 94.0%;and significantly inhibited their growth with apoptosis rate up to 73.0%.ILips were shown to be effective in promoting macrophage polarization and stimulating immune responses in vitro,and PTX-ILips improved cellular uptake and inhibited tumor cell migration and proliferation.In vivo,we evaluated ILips and PTX-ILips accumulation and immune response.In vivo,ILips has excellent in vivo accumulation capacity,and upon reaching the tumor site aCD47 and liposomes co-localized with macrophages and tumor cells respectively.After PTX-ILips treatment,M1 macrophage(F4/80~+CD11b~+CD80~+)levels were increased at the tumor site;CD4 T-cells and CD8 T-cells were increased at the tumor site and in the systemic blood;in addition,IL-6 and TNF-αlevels were increased and IL-10 and TGF-βlevels were decreased in the blood,further demonstrates that the treatment triggers an effective macrophage polarization and systemic immune response.Finally,we evaluated the anti-tumour efficacy and inhibition of recurrence and metastasis of TNBC.Inhibition of tumour growth was significant after PTX-ILips treatment,while HE staining showed that the tumor site was significantly necrotic after treatment,lung metastasis was significantly improved,there were no lesions in major organs,and the survival cycle was increased to 33.3%within 60 days;the tumor recurrence model mice had almost no recurrence and lung metastasis was significantly inhibited after PTX-ILips treatment,and the survival cycle could be The survival period could be improved to 66.7%within 60 days.These results demonstrate that PTX-ILips has good anti-tumour,tumour recurrence and metastasis inhibiting ability in vivo.Conclusion:A series of studies have shown that in the TNBC microenvironment,the PTX-ILips of the"holistic"treatment strategy released aCD47 in response to MMP2,leading to efficient polarization from TAMs into M1 macrophages,which activated the systemic immune response and improved phagocytosis.The enzymatically cleaved PTX liposomes act on MDA-MB-231 cells and synergistically inhibit tumor cell proliferation and metastasis together with M1 macrophage-mediated immune effects.The synergistic therapeutic strategy based on the reprogramming of TAMs in TNBC with co-located drug release at the tumour site,which provides a novel and promising design idea for clinical treatment.