Thus we believe that this aptamer-mediated toxin gene delivery, a protein-free approach which causes tumor cell death, may represent an innovative tool to fight GBM. Materials and Methods Biochemicals Cell Death Detection Elisa kit was purchased MCC950 sodium from Roche (Penzberg, Germany). the cytotoxic effect. Rather than apoptosis, cell death has features resembling autophagic or methuosis-like mechanisms. These main findings support the proof-of-concept of using PEI-polyplexed APTSAP for local delivery in rat glioblastoma models. expression (Xu MCC950 sodium et al., 2001). AS1411 is a 26-mer G-rich DNA aptamer used as a targeting agent to deliver nanoparticles, oligonucleotides, and small molecules into cancer cells overexpressing nucleolin (Bates et al., 2009; Bates et al., 2017; Esposito et al., 2018). It binds to the cell surface nucleolin (Mongelard and Bouvet, 2010; Reyes-Reyes et al., 2010; MCC950 sodium Reyes-Reyes et al., 2015; Bates et al., 2017) leading to a selective uptake, presumably by macropinocytosis (Reyes-Reyes et al., 2010; Gao et al., 2014) and further disruption of nucleolin-mediated intracellular trafficking (Koutsioumpa and Papadimitriou, 2014). Unconjugated AS1411 has shown activity against a wide range of solid and blood cancers in preclinical experiments, and from 2005 to 2011, Aptamera then called Antisoma, a british biotechnology company, started a Phase 1 clinical trial with AS1411 (renamed ACT-GRO-777) and performed a Phase 2b trial targeting renal carcinoma and acute myeloid leukemia obtaining excellent results (Laber et al., 2007; Rizzieri et al., 2010; Rosenberg et al., 2014). Actually, however, there are no further clinical trials with ACT-GRO-777 after Phase 2b was terminated. One of the most clear-cut results obtained in these trials has been the observed time course of AS1411 effects against cancer cells. In fact, unlike other chemotherapeutic agents, maximum cytotoxicity was reached only after long AS1411 exposures to cancer cell lines (2C4?days), therefore the patients in clinical trials were treated with a continuous infusion of AS1411 for 4C7?days with steady-state plasma concentrations in the range Rabbit Polyclonal to Claudin 2 of 1C6?M (Rizzieri et al., 2010). Although nude AS1411 clinical trials have shown promising results, this molecule has been further explored i) for cancer-selective drug delivery, directly attaching AS1411 to gold nanostructures (Rosenberg et al., 2014; Malik et al., 2015), small chemotherapy drugs (Lale et al., 2014; Taghdisi et al., 2016; Abnous et al., 2018), peptides (Rajabnejad et al., 2018), polymers (Yang et al., 2018) and ii) used as an imaging agent by linking, for example, quantum dots (Alibolandi et al., 2014), PET isotopes (Li et al., 2014) and Raman nanoprobes (Wen et al., 2019). Graphene oxide, Doxorubicin, Gd2O3 linked to AS1411 were also used as theranostics agents (Mosafer et al., 2017; Li et al., 2018). AS1411-linked conjugates have been tested in animal models for studying their therapeutic effects. Stable nanoparticles consisting of 6?nm gold nanospheres coated with 40 strands of AS1411 block tumor growth in nude mice bearing both human breast cancer xenografts and neuroblastoma showing an increase of anti-proliferative activity as compared to unconjugated AS1411 (Rosenberg et al., 2014). U87MG cells treatment with AS1411-functionalized poly (l–glutamyl-glutamine)-paclitaxel (PGG-PTX) nanoconjugates showed a 3.5 fold greater cell growth inhibition than that of unconjugated PGG-PTX; this was due to AS1411-nucleolin mediated endocytosis of PGG-PTX, and, indeed, the AS1411 conjugation enhanced the accumulation of AS1411-PGG-PTX nanoconjugates in different organs of glioblastoma-bearing nude mice, after 24?h intravenous injection. The median survival time of mice within the AS1411-PGG-PTX nanoconjugate group was significantly longer than that of the PGG-PTX nanoconjugate mice group, showing higher numbers of apoptotic cells detected in the AS1411-PGG-PTX group (Luo et al., 2017). In this paper, we describe the use of the aptamer AS1411 (APT) DNA sequence embedded in a plasmid to deliver the gene of the plant toxin saporin into glioblastoma cancer cells. Saporin is a plant ribosome-inactivating protein (RIP) (Polito et al., 2013) used for the.