SciCombinator

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Concept: Anthracycline

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Hyaluronic acid is a naturally ionic polysaccharide with cancer cell selectivity. It is an ideal candidate material for delivery of anticancer agents. In this study, hyaluronic acid (HA) micro-hydrogel loaded with anticancer drugs was prepared by the biotin-avidin system approach. Firstly, carboxyl groups on HA were changed into amino groups with adipic acid dihydrazide (ADH) to graft with biotin by 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride named as HA-biotin. When HA-biotin solution mixed with doxorubicin hydrochloride (DOX·HCl) was blended with neutravidin, the micro-hydrogels would be formed with DOX loading. If excess biotin was added into the microgel, it would be disjointed, and DOX will be released quickly. The results of the synthesis procedure were characterized by (1)H-NMR and FTIR; ADH and biotin have been demonstrated to graft on the HA molecule. A field emission scanning electron microscope was used to observe morphologies of HA micro-hydrogels. Furthermore, the in vitro DOX release results revealed that the release behaviors can be adjusted by adding biotin. Therefore, the HA micro-hydrogel can deliver anticancer drugs efficiently, and the rate of release can be controlled by biotin-specific bonding with the neutravidin. Consequently, the micro-hydrogel will perform the promising property of switching in the specific site in cancer therapy.

Concepts: DNA, Cancer, Breast cancer, Oncology, Chemotherapy, Scanning electron microscope, Doxorubicin, Anthracycline

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The treatment of acute promyelocytic leukemia has improved considerably after recognition of the effectiveness of all-trans-retinoic acid (ATRA), anthracycline-based chemotherapy, and arsenic trioxide (ATO). Here we report the use of all 3 agents in combination in an APML4 phase 2 protocol. For induction, ATO was superimposed on an ATRA and idarubicin backbone, with scheduling designed to exploit antileukemic synergy while minimizing cardiotoxicity and the severity of differentiation syndrome. Consolidation comprised 2 cycles of ATRA and ATO without chemotherapy, followed by 2 years of maintenance with ATRA, oral methotrexate, and 6-mercaptopurine. Of 124 evaluable patients, there were 4 (3.2%) early deaths, 118 (95%) hematologic complete remissions, and all 112 patients who commenced consolidation attained molecular complete remission. The 2-year rate for freedom from relapse is 97.5%, failure-free survival 88.1%, and overall survival 93.2%. These outcomes were not influenced by FLT3 mutation status, whereas failure-free survival was correlated with Sanz risk stratification (P[trend] = .03). Compared with our previously reported ATRA/idarubicin-based protocol (APML3), APML4 patients had statistically significantly improved freedom from relapse (P = .006) and failure-free survival (P = .01). In conclusion, the use of ATO in both induction and consolidation achieved excellent outcomes despite a substantial reduction in anthracycline exposure. This trial was registered at the Australian New Zealand Clinical Trials Registry (www.anzctr.org.au) as ACTRN12605000070639.

Concepts: Chemotherapy, Leukemia, Blood disorders, Acute promyelocytic leukemia, Anthracycline, Arsenic trioxide, Antineoplastic drugs, Retinoic acid syndrome

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Magnetic nanoparticles (NPs) loaded with antitumor drugs in combination with an external magnetic field (EMF)-guided delivery can improve the efficacy of treatment and may decrease serious side effects. The purpose of this study was 1) to investigate application of PEG modified GMNPs (PGMNPs) as a drug carrier of the chemotherapy compound doxorubicin (DOX) in vitro; 2) to evaluate the therapeutic efficiency of DOX-conjugated PGMNPs (DOX-PGMNPs) using an EMF-guided delivery in vivo.

Concepts: Cancer, Breast cancer, Magnetic field, Nanoparticle, Chemotherapy, Doxorubicin, Anthracycline, Magnetic nanoparticles

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Anthracycline chemotherapeutic agents carry the well-recognised risk of cardiotoxicity. Previous methods to evaluate cardiac function are useful, but have significant limitations. We sought to determine the left ventricular strain and strain rate of paediatric cancer patients with normal fractional shortening treated with anthracyclines using the latest ultrasound feature-tracking technology. Patients and methods Echocardiograms on cancer patients before anthracycline exposure and following completion of treatment were retrospectively analysed using Velocity Vector Imaging software in the circumferential and longitudinal planes. The same analysis was performed on matched controls. Only patients with a fractional shortening ≥28% were included.

Concepts: Cancer, Oncology, Chemotherapy, Leukemia, Doxorubicin, Anthracycline, Experimental cancer treatment, Epirubicin

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BACKGROUND: The late cardiotoxic effects of anthracycline chemotherapy influence morbidity and mortality in the growing population of childhood cancer survivors. Even with lower anthracycline doses, evidence of adverse cardiac remodeling and reduced exercise capacity exist. We aim to examine the relationship between cardiac structure, function and cardiovascular magnetic resonance (CMR) tissue characteristics with chemotherapy dose and exercise capacity in childhood cancer survivors. METHODS: Thirty patients (15 +/- 3 years), at least 2 years following anthracycline treatment, underwent CMR, echocardiography, and cardiopulmonary exercise testing (peak VO2). CMR measured ventricular function, mass, T1 and T2 values, and myocardial extracellular volume fraction, ECV, a measure of diffuse fibrosis based on changes in myocardial T1 values pre- and post-gadolinium. Cardiac function was also assessed with conventional and speckle tracking echocardiography. RESULTS: Patients had normal LVEF (59 +/- 7%) but peak VO2 was 17% lower than age-predicted normal values and were correlated with anthracycline dose (r = -0.49). Increased ECV correlated with decreased mass/volume ratio (r = -0.64), decreased LV wall thickness/height ratio (r = -0.72), lower peak VO2(r = -0.52), and higher cumulative dose (r = 0.40). Echocardiographic measures of systolic and diastolic function were reduced compared to normal values (p < 0.01), but had no relation to ECV, peak VO2 or cumulative dose. CONCLUSIONS: Myocardial T1 and ECV were found to be early tissue markers of ventricular remodeling that may represent diffuse fibrosis in children with normal ejection fraction post anthracycline therapy, and are related to cumulative dose, exercise capacity and myocardial wall thinning.

Concepts: Blood, Cardiology, Ejection fraction, Heart, Echocardiography, Blood pressure, Chemotherapy, Anthracycline

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Combination of chemotherapy and photothermal therapy has emerged as a promising strategy for cancer therapy. To assure the chemotherapeutic drug and photothermal agent could be simultaneously delivered to tumor region to exert their synergistic effect, a safe and efficient delivery system is highly desirable. Herein, we fabricated doxorubicin (DOX) and indocyanine green (ICG) loaded poly (lactic-co-glycolic acid) (PLGA)-lecithin-polyethylene glycol (PEG) nanoparticles (DINPs) using a single-step sonication method. The DINPs exhibited good monodispersity, excellent fluorescence/size stability, and consistent spectra characteristics compared with free ICG or DOX. Moreover, the DINPs showed higher temperature response, faster DOX release under laser irradiation, and longer retention time in tumor. In the meantime, the fluorescence of DOX and ICG in DINPs was also visualized for the process of subcellular location in vitro and metabolic distribution in vivo. In comparison with chemo or photothermal treatment alone, the combined treatment of DINPs with laser irradiation synergistically induced the apoptosis and death of DOX-sensitive MCF-7 and DOX-resistant MCF-7/ADR cells, and suppressed MCF-7 and MCF-7/ADR tumor growth in vivo. Notably, no tumor recurrence was observed after only a single dose of DINPs with laser irradiation. Hence, the well-defined DINPs exhibited great potential in targeting cancer imaging and chemo-photothermal therapy.

Concepts: Immune system, DNA, Cancer, Breast cancer, Oncology, Chemotherapy, Doxorubicin, Anthracycline

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This systematic review and meta-analysis compared the efficacy of different anthracyclines and anthracycline dosing schedules for induction therapy in acute myeloid leukaemia in children and adults younger than 60 years of age. Twenty-nine randomized controlled trials were eligible for inclusion in the review. Idarubicin (IDA), in comparison to daunorubicin (DNR), reduced remission failure rates (risk ratio (RR) 0·81; 95% confidence interval (CI), 0·66-0·99; P = 0·04), but did not alter rates of early death or overall mortality. Superiority of IDA for remission induction was limited to studies with a DNR/IDA dose ratio <5 (ratio <5: RR 0·65; 95% CI, 0·51-0·81; P < 0·001; ratio ≥5: RR 1·03; 95% CI, 0·91-1·16; P = 0·63). Higher-dose DNR, compared to lower-dose DNR, was associated with reduced rates for remission failure (RR 0·75; 95% CI, 0·60-0·94; P = 0·003) and overall mortality (RR 0·83; 95% CI, 0·75-0·93; P < 0·001), but not for early death. Comparisons of several other anthracycline derivates did not reveal significant differences in outcomes. Survival estimates in adults suggest that both high-dose DNR (90 mg/m(2) daily × 3 or 50 mg/m(2) daily × 5) and IDA (12 mg/m(2) daily × 3) can achieve 5-year survival rates of between 40 and 50 percent.

Concepts: Epidemiology, Medical statistics, Randomized controlled trial, Leukemia, Acute myeloid leukemia, Anthracycline, Daunorubicin, Idarubicin

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Doxorubicin (DOX) is one of the most effective anti-cancer drugs, but its therapeutic efficacy is greatly hampered by its non-specific delivery to the target tissue and the resultant cumulative cardiotoxicity and nephrotoxicity. In order to overcome this limitation, we prepared a folate-bovine serum albumin (BSA)-cis-aconitic anhydride-doxorubicin prodrug, denoted by FA-BSA-CAD. A tumor-targeting agent, folic acid, was linked to BSA to increase the selective targeting ability of the conjugate. BSA provided a large number of reactive sites for multivalent coupling of bioactive molecules and improved the water-solubility of the prodrug. DOX is attached to the BSA via a pH-sensitive linker, cis-aconitic anhydride, which hydrolyzes in the acidic lysosomal environment to allow pH-responsive release of DOX. The in vitro results demonstrate a pH-responsive drug release under different pH conditions. Furthermore, the targeting ability and therapeutic efficacy of the prodrug were assessed both in vitro and in vivo. The results demonstrate that FA-BSA-CAD prodrug selectively targeted tumor cells and tissue, with associated reduction in non-specific toxicity to the normal cells. More importantly, the therapeutic efficacy of the prodrug for FA-positive tumors increased compared to the non-conjuagted DOX.

Concepts: DNA, Cancer, Oncology, Chemotherapy, Tumor, Neoplasm, Efficacy, Anthracycline

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To investigate whether alterations of myocardial strain and high-sensitive cardiac troponin T (cTnT) could predict future cardiac dysfunction in patients after epirubicin exposure.

Concepts: Chemotherapy, Prediction, Futurology, Future, Cardiac muscle, Troponin, Forecasting, Anthracycline

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High-molecular-weight (MW) polymers (>50,000 Da) can be conjugated to chemotherapy drugs in order to improve their tumor accumulation, while low MW polymers ≤10,000 Da are often overlooked due to faster plasma clearance. Small polymers, however, may facilitate deeper tumor penetration.

Concepts: DNA, Cancer, Oncology, Chemotherapy, Doxorubicin, Anthracycline, Chemotherapeutic agents, Topotecan