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Veronesi, M. C.

Publications and source records attributed to Veronesi, M. C..

2 recordsLinked to original sources
bioRxiv2020

Development of Targetable Multi-Drug Nanoparticles for Glioblastoma Treatment and In Vitro Evaluation in Glioblastoma Stem Cells

Glioblastoma (GBM) is a malignant brain tumor with a poor long-term prognosis. The current median survival is approximately fifteen to twenty months with the standard of care therapy which includes surgery, radiation, and chemotherapy. An important factor contributing to recurrence of GBM is high resistance of GBM cancer stem cells (CSCs) to several anticancer drugs, for which a systemically delivered single drug approach will be unlikely to produce a viable cure. Therefore, multidrug therapies have the potential to improve the survival time. Currently, only temozolomide (TMZ), which is a DNA alkylator, affects overall survival in GBM patients. CSCs regenerate rapidly and over-express a methyl transferase which overrides the DNA-alkylating mechanism of TMZ, leading to drug resistance. Idasanutlin (RG7388, R05503781) is a potent, selective MDM2 antagonist that additively kills GBM CSCs when combined with TMZ. Nanotechnology is an emerging field that shows great promise in drug delivery and diagnostics. The ability to combine both therapy and imaging allows real time assessment of drug delivery in vivo for the field of theranostics. To develop a multi-drug therapy using multi-functional nanoparticles (NPs) that preferentially target the GBM CSC subpopulation and provide in vivo preclinical imaging capability. Polymer-micellar NPs composed of poly(styrene-b-ethylene oxide) (PS-b-PEO) and poly(lactic-co-glycolic) acid (PLGA) were developed investigating both single and double emulsion fabrication techniques as well as combinations of TMZ and RG7388. The NPs were covalently bound to a 15-base-pair CD133 aptamer in order to target the CD133 antigen expressed on the surface of GBM CSC subpopulation. For theranostic functionality, the NPs were also labelled with a radiotracer, Zirconium-89 (89Zr). The NPs maintained a small size of less than 100 nm, a low negative charge and exhibited the ability to effectively target and kill the CSC subpopulation. In addition, the conjugation of the CD133 aptamer was able to promote killing in CSCs leading to the justification of a targeted nanosystem to potentially improve localized therapy in future in vivo models. This work has provided a potentially therapeutic option for GBM specific for CSC targeting and theranostic imaging.

cell biology↗
bioRxiv2020

Tumor-responsive, multifunctional CAR-NK cells cooperate with impaired autophagy to infiltrate and target glioblastoma

Tumor antigen heterogeneity, a severely immunosuppressive tumor microenvironment (TME) and lymphopenia resulting in inadequate immune intratumoral trafficking have rendered glioblastoma (GBM) highly resistant to therapy. As a result, GBM immunotherapies have failed to demonstrate sustained clinical improvements in patient overall survival (OS). To overcome these obstacles, here we describe a novel, sophisticated combinatorial platform for GBM: the first multifunctional immunotherapy based on genetically-engineered, human NK cells bearing multiple anti-tumor functions, including local tumor responsiveness, that addresses key drivers of GBM resistance to therapy: antigen escape, poor immune cell homing, and immunometabolic reprogramming of immune responses. We engineered dual-specific CAR-NK cells to bear a third functional moiety that is activated in the GBM TME and addresses immunometabolic suppression of NK cell function: a tumor-specific, locally-released antibody fragment which can inhibit the activity of CD73 independently of CAR signaling and decrease the local concentration of adenosine. The multifunctional human NK cells targeted patient-derived GBM xenografts, demonstrated local tumor site specific activity in the tissue and potently suppressed adenosine production. We also unveil a complex reorganization of the immunological profile of GBM induced by inhibiting autophagy. Pharmacologic impairment of the autophagic process not only sensitized GBM to antigenic targeting by NK cells, but promoted a chemotactic profile favorable to NK infiltration. Taken together, our study demonstrates a promising new NK cell-based combinatorial strategy that can target multiple clinically-recognized mechanisms of GBM progression simultaneously.

immunology↗