Gold nanoparticles and radiofrequency in experimental models for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most lethal and chemo-refractory cancers, clearly, alternative treatment strategies are needed. We utilized 10 nm gold nanoparticles as a scaffold to synthesize nanoconjugates bearing a targeting antibody (cetuximab, C225) and gemcitabine. Loading efficiency of gemcitabine on the gold nanoconjugates was 30%. Targeted gold nanoconjugates in combination with RF were selectively cytotoxic to EGFR expressing Hep3B and SNU449 cells when compared to isotype particles with/without RF (P < 0.05). In animal experiments, targeted gold nanoconjugates halted the growth of subcutaneous Hep3B xenografts in combination with RF exposure (P < 0.05). These xenografts also demonstrated increased apoptosis, necrosis and decreased proliferation compared to controls. Normal tissues were unharmed. We have demonstrated that non-invasive RF-induced hyperthermia when combined with targeted delivery of gemcitabine is more effective and safe at dosages ~ 275-fold lower than the current clinically-delivered systemic dose of gemcitabine

SMARCB1 regulates the hypoxic stress response in sickle cell trait during the pathogenesis of renal medullary carcinoma.

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Bioengineered Human Arginase I with Enhanced Activity and Stability Controls Hepatocellular and Pancreatic Carcinoma Xenografts1

Hepatocellular carcinoma (HCC) and pancreatic carcinoma (PC) cells often have inherent urea cycle defects rendering them auxotrophic for the amino acid l-arginine (l-arg). Most HCC and PC require extracellular sources of l-arg and undergo cell cycle arrest and apoptosis when l-arg is restricted. Systemic, enzyme-mediated depletion of l-arg has been investigated in mouse models and human trials. Non-human enzymes elicit neutralizing antibodies, whereas human arginases display poor pharmacological properties in serum. Co2+ substitution of the Mn2+ metal cofactor in human arginase I (Co-hArgI) was shown to confer more than 10-fold higher catalytic activity (kcat/Km) and 5-fold greater stability. We hypothesized that the Co-hArgI enzyme would decrease tumor burden by systemic elimination of l-arg in a murine model. Co-hArgI was conjugated to 5-kDa PEG (Co-hArgI-PEG) to enhance circulation persistence. It was used as monotherapy for HCC and PC in vitro and in vivo murine xenografts. The mechanism of cell death was also investigated. Weekly treatment of 8 mg/kg Co-hArgI-PEG effectively controlled human HepG2 (HCC) and Panc-1 (PC) tumor xenografts (P = .001 and P = .03, respectively). Both cell lines underwent apoptosis in vitro with significant increased expression of activated caspase-3 (P < .001). Furthermore, there was evidence of autophagy in vitro and in vivo. We have demonstrated that Co-hArgI-PEG is effective at controlling two types of l-arg-dependent carcinomas. Being a nonessential amino acid, arginine deprivation therapy through Co-hArgI-PEG holds promise as a new therapy in the treatment of HCC and PC

Structural Color Patterns by Electrohydrodynamic Jet Printed Photonic Crystals

In this work, we demonstrate the fabrication of photonic crystal patterns with controllable morphologies and structural colors utilizing electrohydrodynamic jet (E-jet) printing with colloidal crystal inks. The final shape of photonic crystal units is controlled by the applied voltage signal and wettability of the substrate. Optical properties of the structural color patterns are tuned by the self-assembly of the silica nanoparticle building blocks. Using this direct printing technique, it is feasible to print customized functional patterns composed of photonic crystal dots or photonic crystal lines according to relevant printing mode and predesigned tracks. This is the first report for E-jet printing with colloidal crystal inks. Our results exhibit promising applications in displays, biosensors, and other functional devices