Lentinan-based pH-responsive nanoparticles achieve the combination therapy of tumors

Leveraging cancer microenvironment pH shift for actuation-induced multidrug release from chitosan/carboxymethyl cellulose bilayer film

In this work, we leverage the pH shift of the tumor microenvironment to achieve controlled, multidrug release from an implantable, pH-responsive bilayer film composed of chitosan (CS) and carboxymethyl cellulose (CMC). Drug release is driven by out-of-plane actuation, where curvature is induced in response to acidic pH, serving as a physiological stimulus. The kinetics of release are modulated by the degree of curvature and the rate of actuation at a given pH. This system enables programmable delivery of a combination of cisplatin (Cis), 5-fluorouracil (5-Fu), and quercetin (Que), targeting multiple cancer pathways to combat drug resistance. In vitro studies with MDA-MB-231 breast cancer cells demonstrated a four-fold increase in cytotoxicity compared to individual drugs, attributed to synergistic effects and controlled release. Additionally, ex-ovo chick chorioallantoic membrane (CAM) assays confirmed the system's antiangiogenic potential, with significant downregulation of key markers, including Vascular Endothelial Growth Factor A (VEGFA), Fibroblast Growth Factor 2 (FGF2), and Angiopoietin 1 (ANG1). Overall, this platform offers a promising strategy for site-specific, sustained delivery of combination therapies in complex cancer environments.

Natural polysaccharide-small molecule smart responsive nanogels: Design, synthesis, and synergistic chemoimmunotherapy for tumors

Cancer poses a significant medical challenge worldwide. Research into tumor biology has revealed the prevalence of acidic conditions and abnormally high levels of reactive oxygen species (ROS) within the tumor microenvironment. In response to these findings, a ROS-responsive crosslinker, (((oxalylbis(oxy))bis(methylene))bis(4,1-phenylene))diboronic acid (OBA), was designed and synthesized using (4-hydroxymethyl)phenylboronic acid and ethanedioyl chloride as reactants. pH-responsive boronate ester bonds were formed between the diboronic acid groups of the crosslinker and the dihydroxyl groups of the naturally occurring active Astragalus polysaccharide (ASP). This resulted in the successful construction of pH/ROS dual-responsive nanogels (BAI@ASPOBA) loaded with the chemotherapeutic natural small molecule baicalein (BAI). Characterization of BAI@ASPOBA through molecular dynamics simulations and other methods demonstrated that it not only inhibited the proliferation of A549 tumor cells in vitro but also exhibited remarkable anti-tumor activity in vivo, along with excellent safety and biocompatibility. Further mechanistic studies revealed that the anti-tumor activity arises from the synergistic enhancement of the chemotherapeutic effects of BAI and the natural polysaccharide ASP. Specifically, the constructed BAI@ASPOBA nanogels enhanced the anti-tumor efficacy of BAI, while ASP, serving as the carrier for the nanomaterials, played an immunostimulatory role, facilitating tumor immunotherapy. The design and development of the novel BAI@ASPOBA nanogels in this study are anticipated to provide a new and effective treatment strategy for cancer therapy.