Methotrexate is a folic acid antagonist and its incorporation into nanoformulations is a promising strategy to increase the drug antiproliferative effect on human breast cancer cells by overexpressing folate receptors. To evaluate the efficiency and selectivity of nanoformulations containing methotrexate and its diethyl ester derivative, using two mechanisms of drug incorporation (encapsulation and surface functionalization) in the in vitro cellular uptake and antiproliferative activity in non-tumoral immortalized human keratinocytes (HaCaT) and in human breast carcinoma cells (MCF-7). Methotrexate and its diethyl ester derivative were incorporated into multiwall lipid-core nanocapsules with hydrodynamic diameters lower than 160 nm and higher drug incorporation efficiency. The nanoformulations were applied to semiconfluent HaCaT or MCF-7 cells. After 24 h, the nanocapsules were internalized into HaCaT and MCF-7 cells; however, no significant difference was observed between the nanoformulations in HaCaT (low expression of folate receptors), while they showed significantly higher cellular uptakes than the blank-nanoformulation in MCF-7, which was the highest uptakes observed for the drug functionalized-nanocapsules. No antiproliferative activity was observed in HaCaT culture, whereas drug-containing nanoformulations showed antiproliferative activity against MCF-7 cells. The effect was higher for drug-surface functionalized nanocapsules. In conclusion, methotrexate-functionalized-nanocapsules showed enhanced and selective antiproliferative activity to human breast cancer cells (MCF-7) being promising products for further in vivo pre-clinical evaluations.

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At the tested doses, Uncaria tomentosa had a positive effect on myeloid progenitor number and is promising for use with chemotherapy to minimize the adverse effects of this treatment. These results support the belief of the Asháninkas, who have classified Uncaria tomentosa as a 'powerful plant'.

Melanoma is a severe metastatic skin cancer with poor prognosis and no effective treatment. Therefore, novel therapeutic approaches using nanotechnology have been proposed to improve therapeutic effectiveness. Lipid-core nanocapsules (LNCs), prepared with poly(ε-caprolactone), capric/caprylic triglyceride, and sorbitan monostearate and stabilized by polysorbate 80, are efficient as drug delivery systems. Here, we investigated the effects of acetyleugenol-loaded LNC (AcE-LNC) on human SK-Mel-28 melanoma cells and its therapeutic efficacies on melanoma induced by B16F10 in C57B6 mice. LNC and AcE-LNC had z -average diameters and zeta potential close to 210 nm and -10.0 mV, respectively. CytoViva ® microscopy images showed that LNC and AcE-LNC penetrated into SK-Mel-28 cells, and remained in the cytoplasm. AcE-LNC in vitro treatment (18–90×10 9 particles/mL; 1 hour) induced late apoptosis and necrosis; LNC and AcE-LNC (3–18×10 9 particles/mL; 48 hours) treatments reduced cell proliferation and delayed the cell cycle. Elevated levels of nitric oxide were found in supernatant of LNC and AcE-LNC, which were not dependent on nitric oxide synthase expressions. Daily intraperitoneal or oral treatment (days 3–10 after tumor injection) with LNC or AcE-LNC (1×10 12 particles/day), but not with AcE (50 mg/kg/day, same dose as AcE-LNC), reduced the volume of the tumor; nevertheless, intraperitoneal treatment caused toxicity. Oral LNC treatment was more efficient than AcE-LNC treatment. Moreover, oral treatment with nonencapsulated capric/caprylic triglyceride did not inhibit tumor development, implying that nanocapsule supramolecular structure is important to the therapeutic effects. Together, data herein presented highlight the relevance of the supramolecular structure of LNCs to toxicity on SK-Mel-28 cells and to the therapeutic efficacy on melanoma development in mice, conferring novel therapeutic mechanisms to LNC further than a drug delivery system.

Atherosclerosis can be originated from the accumulation of modified cholesterol-rich lipoproteins in the arterial wall. The electronegative LDL, LDL(-), plays an important role in the pathogenesis of atherosclerosis once this cholesterol-rich lipoprotein can be internalized by macrophages, contributing to the formation of foam cells, and provoking an immune-inflammatory response. Herein, we engineered a nanoformulation containing highly pure surface-functionalized nanocapsules using a single-chain fragment variable (scFv) reactive to LDL(-) as a ligand and assessed whether it can affect the LDL(-) uptake by primary macrophages and the progression of atherosclerotic lesions in Ldlr−/− mice. The engineered and optimized scFv-anti-LDL(-)-MCMN-Zn nanoformulation is internalized by human and murine macrophages in vitro by different endocytosis mechanisms. Moreover, macrophages exhibited lower LDL(-) uptake and reduced mRNA and protein levels of IL1B and MCP1 induced by LDL(-) when treated with this new nanoformulation. In a mouse model of atherosclerosis employing Ldlr−/− mice, intravenous administration of scFv-anti-LDL(-)-MCMN-Zn nanoformulation inhibited atherosclerosis progression without affecting vascular permeability or inducing leukocytes-endothelium interactions. Together, these findings suggest that a scFv-anti-LDL(-)-MCMN-Zn nanoformulation holds promise to be used in future preventive and therapeutic strategies for atherosclerosis.