Efficient PEGylated Dendrimer Nanoplatform for Codelivery of Hyaluronidase and Methotrexate: a new frontier in chemotherapeutic efficacy and tumor penetration

The condensed extracellular matrix (ECM) surrounding cancer cells results in the formation of a biophysical barrier versus chemotherapeutic drug penetration into deeper regions of many solid malignancies. To cope with this drawback, the present study inquired the therapeutic potential of a hyaluronidase (Hyal)-modified hyperbranched poly(amide amine) (PAMAM) loaded with an anticancer drug, methotrexate (MTX), to improve breast cancer chemoresistance. The focus is on reducing the hyaluronic acid accumulation as a major component of the tumor ECM. The decoration of the prepared pH-responsive nanoplatform with a relatively low density layer of polyethylene glycol (PEG) improved its stability and performance. These processes were characterized by different instruments and an enzymatic activity assessment. Despite the short half-life of pristine hyaluronidase, the Hyal-immobilized nanoplatform displayed enhanced enzyme stability, especially against protease degradation, and prolonged half-life after incubation in human plasma. The MTX loaded into carboxylate nanocarrier (PAMAM-MTX/SA/Hyal/PEG) exhibited an outstanding ability for controlled release of MTX. The results of the hemolysis assay confirmed the good blood compatibility of the as-prepared nanoplatform. The cytotoxicity assessment of various nanoformulations using an MTS-based assay on MCF-7 and MCF-10A cell lines revealed that PAMAM-MTX/SA/Hyal/PEG was more efficient against tumor cells than free MTX over 72 h. In addition, the effect of PAMAM-MTX/SA/Hyal/PEG against MCF-7 cells showed noteworthy induction of apoptosis and facilitated uptake by MCF-7 cells and penetration in MCF-7 3D tumor spheroids compared to free MTX. Thus, the synthesized nanoplatform indicated in vitro controlled release of MTX with the advantage of an adjuvant Hyal-based nanosystem. This outlook suggests a novel multifunctional nanoplatform to improve anticancer drug delivery systems by effective modulation of the tumor microenvironment.