Yan Chen,Ming Zhang,Zhifang Liu,Ning Zhang,Qingpeng Wang
Tumor microenvironment (TME) is a pivotal factor driving the tumor metastasis and leading to the failure of tumor therapy. Here, a series of ursodeoxycholic acid platinum(IV) conjugates with potency in remodeling the TME through suppressing JAK2/STAT3 signaling was developed. A candidate was screened out, which displayed potent antiproliferative and antimetastatic performance both in vitro and in vivo. It displayed superior pharmacokinetic properties compared to cisplatin. Serious DNA injury was induced, and then mitochondria-mediated apoptosis was initiated through the Bcl-2/Bax/Caspase3 pathway. The JAK2/STAT3 and TGF-β1 signaling pathways were remarkably inhibited, and pro-death autophagy was subsequently promoted. The inflammatory and hypoxic TME was suppressed by downregulating COX-2, MMP9, and HIF-1α, which resulted in inhibited angiogenesis in tumors by inhibiting the HIF-1α/VEGFA axis. Additionally, the immunosuppressive TME was reversed by blocking the immune checkpoint PD-L1, further improving the density of CD3+ and CD8+ tumor-infiltrating lymphocytes, and promoting macrophage polarization from M2- to M1-type.
Non-small cell lung cancer (NSCLC) accounts for about 85% of all lung cancers. Traditional chemotherapy for this disease leads to serious side effects. Here we prepared an inhalable oridonin-loaded poly(lactic- co -glycolic)acid (PLGA) large porous microparticle (LPMP) for in situ treatment of NSCLC with the emulsion/solvent evaporation/freeze-drying method. The LPMPs were smooth spheres with many internal pores. Despite a geometric diameter of ~10 µm, the aerodynamic diameter of the spheres was only 2.72 µm, leading to highly efficient lung deposition. In vitro studies showed that most of oridonin was released after 1 h, whereas the alveolar macrophage uptake of LPMPs occurred after 8 h, so that most of oridonin would enter the surroundings without undergoing phagocytosis. Rat primary NSCLC models were built and administered with saline, oridonin powder, gemcitabine, and oridonin-loaded LPMPs via airway, respectively. The LPMPs showed strong anticancer effects. Oridonin showed strong angiogenesis inhibition and apoptosis. Relevant mechanisms are thought to include oridonin-induced mitochondrial dysfunction accompanied by low mitochondrial membrane potentials, downregulation of BCL-2 expressions, upregulation of expressions of BAX, caspase-3 and caspase-9. The oridonin-loaded PLGA LPMPs showed high anti-NSCLC effects after pulmonary delivery. In conclusion, LPMPs are promising dry powder inhalations for in situ treatment of lung cancer.