Inhalable self-assembled albumin nanoparticles for treating drug-resistant lung cancer

Lung cancer nanomedicine: potentials and pitfalls

Lung cancer is by far the most common cause of cancer-related deaths in the world. Nanoparticle-based therapies enable targeted drug delivery for lung cancer treatment with increased therapeutic efficiency and reduced systemic toxicity. At the same time, nanomedicine has the potential for multimodal treatment of lung cancer that may involve 'all-in-one' targeting of several tumor-associated cell types in a timely and spatially controlled manner. Therapeutic approaches, however, are hampered by a translational gap between basic scientists, clinicians and pharma industry due to suboptimal animal models and difficulties in scale-up production of nanoagents. This calls for a disease-centered approach with interdisciplinary basic and clinical research teams with the support of pharma industries.

In vivo biocompatibility, clearance, and biodistribution of albumin vehicles for pulmonary drug delivery

The development of clinically acceptable albumin-based nanoparticle formulations for use in pulmonary drug delivery has been hindered by concerns about the toxicity of nanomaterials in the lungs combined with a lack of information on albumin nanoparticle clearance kinetics and biodistribution. In this study, the in vivo biocompatibility of albumin nanoparticles was investigated following a single administration of 2, 20, and 390 μg/mouse, showing no inflammatory response (TNF-α and IL-6, cellular infiltration and protein concentration) compared to vehicle controls at the two lower doses, but elevated mononucleocytes and a mild inflammatory effect at the highest dose tested. The biodistribution and clearance of ¹¹¹In labelled albumin solution and nanoparticles over 48 h following a single pulmonary administration to mice was investigated by single photon emission computed tomography and X-ray computed tomography imaging and terminal biodistribution studies. ¹¹¹In labelled albumin nanoparticles were cleared more slowly from the mouse lung than ¹¹¹In albumin solution (64.1 ± 8.5% vs 40.6 ± 3.3% at t = 48 h, respectively), with significantly higher (P < 0.001) levels of albumin nanoparticle-associated radioactivity located within the lung tissue (23.3 ± 4.7%) compared to the lung fluid (16.1 ± 4.4%). Low amounts of ¹¹¹In activity were detected in the liver, kidneys, and intestine at time points > 24 h indicating that small amounts of activity were cleared from the lungs both by translocation across the lung mucosal barrier, as well as mucociliary clearance. This study provides important information on the fate of albumin vehicles in the lungs, which may be used to direct future formulation design of inhaled nanomedicines.

Macrophage mediated biomimetic delivery system for the treatment of lung metastasis of breast cancer

The biomimetic delivery system (BDS) based on special types of endogenous cells like macrophages and T cells, has been emerging as a novel strategy for cancer therapy, due to its tumor homing property and biocompatibility. However, its development is impeded by complicated construction, low drug loading or negative effect on the cell bioactivity. The present report constructed a BDS by loading doxorubicin (DOX) into a mouse macrophage-like cell line (RAW264.7). It was found that therapeutically meaningful amount of DOX could be loaded into the RAW264.7 cells by simply incubation, without significantly affecting the viability of the cells. Drug could release from the BDS and maintain its activity. RAW264.7 cells exhibited obvious tumor-tropic capacity towards 4T1 mouse breast cancer cells both in vitro and in vivo, and drug loading did not alter this tendency. Importantly, the DOX loaded macrophage system showed promising anti-cancer efficacy in terms of tumor suppression, life span prolongation and metastasis inhibition, with reduced toxicity. In conclusion, it is demonstrated that the BDS developed here seems to overcome some of the main issues related to a BDS. The DOX loaded macrophages might be a potential BDS for targeted cancer therapy.