ABSTRACT
Cholesterol-rich nanoemulsion (LDE) can carry chemotherapeutic agents in the circulation and can concentrate those agents in the neoplastic and inflammatory tissues. This method improves the biodistribution of the drug and reduces toxicity. However, the structural stability of LDE particles, without or with associated drugs, has not been extensively investigated. The aim of the present study is to investigate the structural stability of LDE and LDE associated to paclitaxel, etoposide or methotrexate in aqueous solution over time by small-angle X-ray scattering (SAXS and Ultra SAXS) and dynamic light scattering (DLS). The results show that LDE and LDE associated with those chemotherapeutic agents had reproducible and stable particle diameter, physical structure, and aggregation behavior over 3-month observation period. As estimated from both DLS and Ultra-SAXS methods, performed at pre-established intervals, the average particle diameter of LDE alone was approx. 32â¯nm, of LDE-paclitaxel was 31â¯nm, of LDE-methotrexate was 35â¯nm and of LDE-etoposide was 36â¯nm. Ultra-SAXS analysis showed that LDE nanoparticles were quasi-spherical, and SAXS showed that drug molecules inside the particles showed a layered-like organization. Formulations of LDE with associated PTX, ETO or MTX were successfully tested in animal experiments and in patients with cancer or with cardiovascular disease, showing markedly low toxicity, good tolerability and possible superior pharmacological action. Our results may be useful for ensuing clinical trials of this novel Nanomedicine tool, by strengthening the knowledge of the structural aspects of those LDE formulations.
Subject(s)
Cholesterol , Emulsions , Methotrexate , Nanoparticles , Emulsions/chemistry , Cholesterol/chemistry , Nanoparticles/chemistry , Methotrexate/chemistry , Humans , Animals , Particle Size , Paclitaxel/chemistry , Paclitaxel/pharmacology , Scattering, Small Angle , Etoposide/chemistry , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , X-Ray Diffraction , Molecular StructureABSTRACT
Allogeneic hematopoietic cell transplantation (HCT) is the treatment of choice for acute myelogenous leukemia (AML) not responding to induction therapy. It is a therapeutic choice for the blast phase of chronic myelogenous leukemia (CML-BP) in patients failing to respond to tyrosine kinase inhibitors (TKIs). Lipid core nanoparticles (LDEs) concentrate severalfold more in blast cells than in corresponding normal cells. Incorporation of anticancer drugs to LDE formulations increases the pharmacologic action and decreases the toxicity. We tested a drug-targeting system, LDE-etoposide plus total body irradiation (TBI; 1200 cGy dose), in 13 patients with AML not responding to the induction therapy and in 2 patients with CML-BP refractory to second-generation TKIs. The mean patient age was 46.7 years (range, 22 to 66 years). The LDE-etoposide dose was escalated at 20, 30, 40, 50, and 60 mg/kg. No patients developed grade 4 or 5 toxicity; however, mucositis grade 3 occurred in 6 patients, 3 patients experienced diarrhea, and 1 patient had an elevated total bilirubin level. No deaths were related to conditioning. All patients were successfully engrafted. The median times to neutrophil and platelet engraftment were 20 ± 5 days and 16 ± 4 days, respectively. Five patients (33.4%) had acute graft-versus-host-disease (GVHD), including 4 grade I, and 1 with grade II, and 8 patients (57.1%) had moderate-to-severe chronic GVHD. This pilot study shows the potential of LDE-etoposide plus TBI as an HCT conditioning regimen in AML patients not responding to the induction and refractory therapies for CML-BP patient. These findings pave the way for subsequent larger clinical trials.
Subject(s)
Graft vs Host Disease , Hematopoietic Stem Cell Transplantation , Leukemia, Myeloid, Acute , Nanoparticles , Adult , Aged , Bone Marrow , Etoposide/therapeutic use , Humans , Induction Chemotherapy , Leukemia, Myeloid, Acute/therapy , Lipids , Middle Aged , Pilot Projects , Transplantation Conditioning , Transplantation, Homologous , Whole-Body Irradiation , Young AdultABSTRACT
Ovarian cancer is often diagnosed at advanced stages, when poorly responsive to standard treatment. First-line treatment consists in schemes including cytoreductive surgery followed by adjuvant chemotherapy schemes with platinum and taxane derivatives. Second-line regimens are based on gemcitabine and liposomal doxorubicin. Third line is often not worthwhile because of the high toxicity with poor response to treatment. Previously, we showed that paclitaxel (PTX) carried in non-protein lipid core nanoparticles (LDE) resembling the chemical structure of LDL has remarkably reduced toxicity. Here, the hypothesis was tested whether PTX-LDE could safely benefit patients in third-line treatment setting. Fourteen women unresponsive to second-line chemotherapy for ovarian cancer, aged 61 ± 10 years, clinical stage IV and TqNqM1, were included. PTX-LDE was administered at 175 mg/m2, 3/3 week dose. Patients were submitted to clinical examinations before each chemotherapy cycle. Serum biochemistry and imaging examinations to monitor disease progression were performed. In total, 74 cycles of chemotherapy were done and, in all cycles, clinical or laboratorial toxicities were not observed. Median progression-free survival (PFS) was 3.0 months (95% CI 2.0-3.9). In four patients, PFS was >6 months and in 2 > 1 year. The unpreceded, striking absence of toxicity and consistently long PFS, compared to previous results, indicate that at least 4 among 14 patients had tumor arrest by the treatment and clear benefit of PTX-LDE at third-line setting. The absence of observable toxicity allows dose escalating to improve response to treatment, as perspective to be tested in the ensuing studies.
Subject(s)
Carcinoma/drug therapy , Lipids/administration & dosage , Nanoparticles/administration & dosage , Neoplasms, Glandular and Epithelial/drug therapy , Ovarian Neoplasms/drug therapy , Paclitaxel/therapeutic use , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Ovarian Epithelial , Chemotherapy, Adjuvant/methods , Deoxycytidine/analogs & derivatives , Deoxycytidine/therapeutic use , Disease Progression , Disease-Free Survival , Doxorubicin/analogs & derivatives , Doxorubicin/therapeutic use , Female , Humans , Polyethylene Glycols/therapeutic use , GemcitabineABSTRACT
OBJECTIVE: The toxicity of anti-cancer chemotherapeutic agents can be reduced by associating these compounds, such as the anti-proliferative agent paclitaxel, with a cholesterol-rich nanoemulsion (LDE) that mimics the lipid composition of low-density lipoprotein (LDL). When injected into circulation, the LDE concentrates the carried drugs in neoplastic tissues and atherosclerotic lesions. In rabbits, atherosclerotic lesion size was reduced by 65% following LDE-paclitaxel treatment. The current study aimed to test the effectiveness of LDE-paclitaxel on inpatients with aortic atherosclerosis. METHODS: This study tested a 175 mg/m2 body surface area dose of LDE-paclitaxel (intravenous administration, 3/3 weeks for 6 cycles) in patients with aortic atherosclerosis who were aged between 69 and 86 yrs. A control group of 9 untreated patients with aortic atherosclerosis (72-83 yrs) was also observed. RESULTS: The LDE-paclitaxel treatment elicited no important clinical or laboratory toxicities. Images were acquired via multiple detector computer tomography angiography (64-slice scanner) before treatment and at 1-2 months after treatment. The images showed that the mean plaque volume in the aortic artery wall was reduced in 4 of the 8 patients, while in 3 patients it remained unchanged and in one patient it increased. In the control group, images were acquired twice with an interval of 6-8 months. None of the patients in this group exhibited a reduction in plaque volume; in contrast, the plaque volume increased in three patients and remained stable in four patients. During the study period, one death unrelated to the treatment occurred in the LDE-paclitaxel group and one death occurred in the control group. CONCLUSION: Treatment with LDE-paclitaxel was tolerated by patients with cardiovascular disease and showed the potential to reduce atherosclerotic lesion size.
Subject(s)
Aortic Diseases/drug therapy , Atherosclerosis/drug therapy , Cholesterol/therapeutic use , Nanoparticles/therapeutic use , Paclitaxel/therapeutic use , Tubulin Modulators/therapeutic use , Aged , Aged, 80 and over , Angiography , Aorta, Thoracic/drug effects , Aortic Diseases/diagnostic imaging , Atherosclerosis/diagnostic imaging , Cholesterol/blood , Drug Delivery Systems , Fat Emulsions, Intravenous/therapeutic use , Female , Humans , Male , Multidetector Computed Tomography , Reproducibility of Results , Time Factors , Treatment Outcome , Triglycerides/bloodABSTRACT
OBJECTIVE: The toxicity of anti-cancer chemotherapeutic agents can be reduced by associating these compounds, such as the anti-proliferative agent paclitaxel, with a cholesterol-rich nanoemulsion (LDE) that mimics the lipid composition of low-density lipoprotein (LDL). When injected into circulation, the LDE concentrates the carried drugs in neoplastic tissues and atherosclerotic lesions. In rabbits, atherosclerotic lesion size was reduced by 65% following LDE-paclitaxel treatment. The current study aimed to test the effectiveness of LDE-paclitaxel on inpatients with aortic atherosclerosis. METHODS: This study tested a 175 mg/m2 body surface area dose of LDE-paclitaxel (intravenous administration, 3/3 weeks for 6 cycles) in patients with aortic atherosclerosis who were aged between 69 and 86 yrs. A control group of 9 untreated patients with aortic atherosclerosis (72-83 yrs) was also observed. RESULTS: The LDE-paclitaxel treatment elicited no important clinical or laboratory toxicities. Images were acquired via multiple detector computer tomography angiography (64-slice scanner) before treatment and at 1-2 months after treatment. The images showed that the mean plaque volume in the aortic artery wall was reduced in 4 of the 8 patients, while in 3 patients it remained unchanged and in one patient it increased. In the control group, images were acquired twice with an interval of 6-8 months. None of the patients in this group exhibited a reduction in plaque volume; in contrast, the plaque volume increased in three patients and remained stable in four patients. During the study period, one death unrelated to the treatment occurred in the LDE-paclitaxel group and one death occurred in the control group. CONCLUSION: Treatment with LDE-paclitaxel was tolerated by patients with cardiovascular disease and showed the potential to reduce atherosclerotic lesion size.
Subject(s)
Humans , Male , Female , Aged , Aged, 80 and over , Aortic Diseases/drug therapy , Cholesterol/therapeutic use , Paclitaxel/therapeutic use , Atherosclerosis/drug therapy , Tubulin Modulators/therapeutic use , Nanoparticles/therapeutic use , Aorta, Thoracic/drug effects , Aortic Diseases/diagnostic imaging , Time Factors , Triglycerides/blood , Angiography , Cholesterol/blood , Reproducibility of Results , Treatment Outcome , Drug Delivery Systems , Atherosclerosis/diagnostic imaging , Fat Emulsions, Intravenous/therapeutic use , Multidetector Computed TomographyABSTRACT
OBJECTIVE: To evaluate the effects of anabolic androgenic steroids (AAS) on chylomicron metabolism. METHODS: An artificial lipid emulsion labeled with radioactive cholesteryl ester (CE) and triglycerides (TG) mimicking chylomicrons was intravenously injected into individuals who regularly weight trained and made regular use of AAS (WT+AAS group), normolipidemic sedentary individuals (SDT group) and individuals who also regularly weight trained but did not use AAS (WT group). Fractional clearance rates (FCR) were determined by compartmental analysis for emulsion plasma decay curves. RESULTS: FCR-CE for the WT+AAS group was reduced (0.0073 ± 0.0079 min(-1), 0.0155 ± 0.0100 min(-1), 0.0149 ± 0.0160 min(-1), respectively; p<0.05), FCR-TG was similar for both the WT and SDT groups. HDL-C plasma concentrations were lower in the WT+AAS group when compared to the WT and SDT groups (22 ± 13; 41 ± 7; 38 ± 13 mg/dL, respectively; p<0.001). Hepatic triglyceride lipase activity was greater in the WT+AAS group when compared to the WT and SDT groups (7243 ± 1822; 3898 ± 1232; 2058 ± 749, respectively; p<0.001). However, no difference was observed for lipoprotein lipase activity. CONCLUSIONS: Data strongly suggest that AAS may reduce the removal from the plasma of chylomicron remnants, which are known atherogenic factors.
Subject(s)
Androgens/pharmacology , Chylomicrons/metabolism , Steroids/pharmacology , Adult , Chylomicrons/chemistry , Humans , Male , Resistance Training , Sedentary Behavior , Triglycerides/chemistryABSTRACT
OBJECTIVE: To evaluate the effects of resistance training (RT) on the metabolism of an LDL-like nanoemulsion and on lipid transfer to HDL, an important step of HDL metabolism. METHODS: LDL-like nanoemulsion plasma kinetics was studied in 15 healthy men under regular RT for 1-4 years (age = 25 ± 5 years, VO(2)peak = 50 ± 6 mL/kg/min) and in 15 healthy sedentary men (28 ± 7 years, VO(2)peak = 35 ± 9 mL/kg/min). LDL-like nanoemulsion labeled with (14)C-cholesteryl-ester and (3)H-free-cholesterol was injected intravenously, plasma samples were collected over 24-h to determine decay curves and fractional clearance rates (FCR). Lipid transfer to HDL was determined in vitro by incubating of plasma samples with nanoemulsions (lipid donors) labeled with radioactive free-cholesterol, cholesteryl-ester, triacylglycerols and phospholipids. HDL size, paraoxonase-1 activity and oxidized LDL levels were also determined. RESULTS: The two groups showed similar LDL and HDL-cholesterol and triacylglycerols, but oxidized LDL was lower in RT (30 ± 9 vs. 61 ± 19 U/L, p = 0.0005). In RT, the nanoemulsion (14)C-cholesteryl-ester was removed twice as fast than in sedentary individuals (FCR: 0.068 ± 0.023 vs. 0.037 ± 0.028, p = 0.002), as well as (3)H-free-cholesterol (0.041 ± 0.025 vs. 0.022 ± 0.023, p = 0.04). While both nanoemulsion labels were removed at the same rate in sedentary individuals, RT (3)H-free-cholesterol was removed slower than (14)C-cholesteryl-ester (p = 0.005). HDL size, paraoxonase 1 and the transfer rates to HDL of the four lipids were the same in both groups. CONCLUSIONS: RT accelerated the clearance of LDL-like nanoemulsion, which probably accounts for the oxidized LDL levels reduction in RT. RT also changed the balance of free and esterified cholesterol FCR's. However, RT had no effect on HDL metabolism related parameters.