Evaluation of in vivo antitumor effects of ANT2 shRNA delivered using PEI and ultrasound with microbubbles

Abstract

Gene therapy using RNA interference can be directed against tumors through various strategies, but has been hindered owing to the inefficiency of non-viral delivery. To evaluate the antitumor effects of adenine nucleotide translocase-2 (ANT2) short hairpin RNA (shRNA) by intraperitoneal injection using the polyethylenimine (PEI) and an ultrasound gene delivery method, human breast carcinoma MDA-MB-231 cells were injected subcutaneously into NOG (NOD/Shi-scid/IL-2Rγ(null)) mice. The results showed greater tumor regression (*P<0.05) as well as an increased survival rate in the group receiving ANT2 shRNA+two types of enhancer relative to the groups receiving ANT2 shRNA without enhancer. These findings demonstrate that the introduction of PEI and ultrasound with SonoVue exerted enhanced antitumor effects in vivo. Although the combination of jet-PEI and ultrasound provided the best results with respect to tumor regression, the antitumor effects from the individual enhancers were approximately equivalent. In addition, we confirmed that there was no toxicity on aspartate aminotransferase and alanine aminotransferase levels in the liver and albumin, blood urea nitrogen or creatine kinase levels in the kidney following the various gene delivery methods.

Drug and gene delivery across the blood–brain barrier with focused ultrasound

“…Despite a high number of publications demonstrating the ability of FUS to deliver gene bearing liposomes[152,153], non-viral polyplexes[154–156], viruses[157–159] and free or MB bound plasmid DNA[160] to non-CNS tissues, there are very few studies that have shown the delivery of systemically administered gene-bearing agents to the CNS with FUS. Indeed, the first successful studies showing delivery of reporter gene-bearing agents across the BBB with FUS were completed as recently at 2012[161–163].…”

VTIQ evaluates antitumor effects of NET‑1 siRNA by UTMD in HCC xenograft models

“…Furthermore, one of the major concerns associated the use of these enhancers in clinical studies is the safety of the therapeutic system ( 38 ). Non-viral vectors are being increasingly used for gene therapy instead of viral vectors, owing to the concerns about the potential induction of immune responses against viral proteins, endogenous virus recombination and oncogenic effects ( 49 ).…”

“…In the present study, it was identified that the UTMD delivery method exhibited potential in improving gene transfection efficiency. The toxicity of the nanobubbles and the ultrasound radiation have also raised crucial safety issues in clinical studies ( 38 ). Therefore, liver and kidney samples were collected from each group of nude mice, and H&E staining was performed to evaluate the safety of the treatment.…”

“…For the toxicity assessment of NET-1 siRNA-conjugated TNBs, standard Harris hematoxylin (5 mg/ml) and eosin (10 mg/ml) (H&E) staining was performed on the liver and kidney samples ( 38 ). The liver and kidney tissues were immersed in 10% formalin for 24 h. Then the slides were placed in processing cassettes, dehydrated through a serial alcohol gradient (50, 70, 80, 85, 90 and 95% anhydrous ethanol twice; 10 min for each step) at 37°C, and embedded in paraffin wax blocks.…”

Recent Advances about Local Gene Delivery by Ultrasound

“…Deshpande et al found that ultrasound combined with PEI could enhance the DNA transfection rate up to 200-fold than naked DNA plasmids [59]. Park et al applied UTMD combined with PEI mediating the adenine nucleotide translocase-2 (ANT2) shRNA to successfully increase the survival rate of xenograft mice and induce the tumor regression [60].…”