In the present study, we evaluated polyethylenimine (PEI) of different molecular weights (MWs) as a DNA complexing agent for its efficiency in transfecting nondifferentiated COS-1 (green monkey fibroblasts) and well-differentiated human submucosal airway epithelial cells (Calu-3). Studying the effect of particle size, zeta potential, presence of serum proteins or chloroquine, it appeared that transfection efficiency depends on the experimental conditions and not on the MW of the PEI used. Comparing transfection efficiencies in both cell lines, we found that PEI was 3 orders of magnitude more effective in COS-1 than in Calu-3 cells, because Calu-3 cells are differentiated and secrete mucins, which impose an additional barrier to gene delivery. Transfection efficiency was strongly correlated to PEI cytotoxicity. Also, some evidence for PEI-induced apoptosis in both cell lines was found. In conclusion, our results indicate that PEI is a useful vector for nonviral transfection in undifferentiated cell lines. However, results from studies in differentiated bronchial epithelial cells suggest that PEI has yet to be optimized for successful gene therapy of cystic fibrosis (CF).

The objectives of this study were to investigate the influence of physicochemical properties of lipid/plasmid complexes on in vivo gene transfer and biodistribution characteristics. Formulations based on 1,2-di-O-octadecenyl-3-trimethylammonium propane (DOTMA) and novel biodegradable cationic lipids, such as ethyl dioleoyl phosphatidylcholine (EDOPC), ethyl palmitoyl myristyl phosphatidylcholine (EPMPC), myristyl myristoyl carnitine ester (MMCE), and oleyl oleoyl L-carnitine ester (DOLCE), were assessed for gene expression after tail vein injection of lipid/plasmid complexes in mice. Gene expression was influenced by cationic lipid structure, cationic lipid-to-colipid molar ratios, plasmid-to-lipid charge ratios, and precondensation liposome size. Detectable levels of human growth hormone (hGH) in serum, human factor IX (hFIX) in plasma, and chloramphenicol acetyltransferase (CAT) in the lung and liver were observed with positively charged lipid/plasmid complexes prepared from 400-nm extruded liposomes with a cationic lipid-to-colipid ratio of 4:1 (mol/mol). Intravenous administration of lipid/CAT plasmid complexes resulted in distribution of plasmid DNA mainly to the lung at 15 min after injection. Plasmid DNA accumulation in the liver increased with time up to 24 hr postinjection. There was a 10-fold decrease in the amount of plasmid DNA in the lung at 15 min after injection, when the lipid/plasmid complex charge ratio was decreased from 3:1 to 0.5:1 (+/-). Bright fluorescent aggregates were evident in in vivo-transfected lung with the positively charged pCMV-CAT/DOLCE:dioleyl phosphatidylethanolamine (DOPE) (1:1, mol/mol) complexes, while more discrete punctate fluorescence was observed with a 4:1 molar ratio of cationic lipid:colipid formulations. Preinjection of polyanions such as plasmid, dextran sulfate, polycytidic acid, and polyinosinic acid decreased hGH expression, whereas the preinjection of both positively charged and neutral liposomes had no effect on hGH serum levels. Of the cationic lipids tested, DOLCE was found to be the most effective potentially biodegradable cationic lipid. A correlation between gene expression and cationic lipid:colipid ratios and lipid-to-plasmid charge ratio was also observed for DOTMA- and DOLCE-based formulations.

A cationic lipid-based gene delivery system composed of N- [(1-(2,3-dioleyloxy)propyl)]-N-N-N-trimethylammonium chloride and cholesterol, at a 4:1 molar ratio, was developed for systemic administration. Plasmid biodistribution and expression were characterized in syngeneic mouse tumor model squamous cell carcinoma VII cells. A reporter gene expression plasmid was used for biodistribution of plasmid and expression. The results showed that lungs and primary tumors were transfected. Fluorescence microscopy showed that fluorescent-labeled transfection complexes were passively targeted to the tumor vasculature and that the endothelial cells internalized the plasmid. Transgene expression was characterized based on duration of expression and dosing schedule. In vivo gene transfer with an interleukin-12 expression plasmid yielded protein levels in blood, lungs, and primary tumor after intravenous administration. Efficacy studies showed that 15 g of interleukin-12 plasmid was sufficient to produce a gene-specific inhibition of primary tumor growth. These results characterize the vascularity of the tumor model, characterize the in vivo gene transfer properties of the plasmid-based gene delivery system, and show that the transgene expression level was sufficient to elicit a biological response by inhibiting tumor growth.

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Patients with cancer transition through the different stages of the cancer care continuum, and into and out of the cancer system, and will see many care providers in many settings (1).These will include General Practitioners (GPs), Community Pharmacists and Nurses as well as consultant led hospital multi-disciplinary teams. These patients require care that is integrated around the patient's needs and seamlessly coordinated across different providers (2) to ensure patients receive the right care, in the right place, at the right time (3).Chemotherapy treatment can be complex and toxic with many potential side effects. It is initiated by specialist consultants in secondary care and is either hospital or home administered. It is described in chemotherapy treatment protocols which support safe, evidence-based and cost effective cancer treatment. These are key documents which inform all involved in the care of the patient regarding the correct drug, dose, route and appropriate adjustments required due to toxicity or side effects. Effective communication and transfer of this information across the interface between primary and secondary care is seen as vital in the integration of care (3, 4).In 2014, the NCCP recommended that each hospital providing cancer services had access to an agreed list of chemotherapy protocols. This followed from the finding of the Oncology Medication Safety Review Report (5) which found that only 8 out of 26 hospitals had specific chemotherapy protocols in place which were available only for use within the hospital.The NCCP proceeded to implement a systematic process for the development of nationally approved chemotherapy protocols to improve communication at transitions in care for patients as they move across settings and providers, particularly from the hospital back into the community in order to support safe, evidence-based, cost effective cancer treatment. This process involves a standardised development and approval process. The protocols are developed in a coordinated fashion under the guidance of Specialist Medical Consultants with input from nursing staff, pharmacists and other healthcare professionals (HCPs). Once approved they are published on the NCCP website (6) where they are available to clinicians, HCPs and the public. These protocols are reviewed every two years at a minimum or when any relevant updates are published.