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Docetaxel (DTX) is found to be very effective against glioma cell in vitro. However, in vivo passage of DTX through BBB is extremely difficult due to the physicochemical and pharmacological characteristics of the drug. No existing formulation is successful in this aspect. Hence, in this study, effort was made to send DTX through blood-brain barrier (BBB) to brain to treat diseases such as solid tumor of brain (glioma) by developing DTX-loaded nanoliposomes. Primarily drug-excipients interaction was evaluated by FTIR spectroscopy. The DTX-loaded nanoliposomes (L-DTX) were prepared by lipid layer hydration technique and characterized physicochemically. In vitro cellular uptake in C6 glioma cells was investigated. FTIR data show that the selected drug and excipients were chemically compatible. The unilamellar vesicle size was less than 50 nm with smooth surface. Drug released slowly from L-DTX in vitro in a sustained manner. The pharmacokinetic data shows more extended action of DTX from L-DTX in experimental rats than the free-drug and Taxotere®. DTX from L-DTX enhanced 100% drug concentration in brain as compared with Taxotere® in 4 h. Thus, nanoliposomes as vehicle may be an encouraging strategy to treat glioma with DTX.

Diagnosis and therapy of brain cancer was often limited due to low permeability of delivery materials across the blood-brain barrier (BBB) and their poor penetration into the brain tissue. This study explored the possibility of utilizing theranostic d-alpha-tocopheryl polyethylene glycol 1000 succinate mono-ester (TPGS) liposomes as nanocarriers for minimally invasive brain-targeted imaging and therapy (brain theranostics). The aim of this work was to formulate transferrin conjugated TPGS coated theranostic liposomes, which contain both docetaxel and quantum dots (QDs) for imaging and therapy of brain cancer. The theranostic liposomes with and without transferrin decoration were prepared and characterized for their particle size, polydispersity, morphology, drug encapsulation efficiency, in-vitro release study and brain theranostics. The particle sizes of the non-targeted and targeted theranostic liposomes were found below 200 nm. Nearly, 71% of drug encapsulation efficiency was achieved with liposomes. The drug release from transferrin conjugated theranostic liposomes was sustained for more than 72 h with 70% of drug release. The in-vivo results indicated that transferrin receptor-targeted theranostic liposomes could be a promising carrier for brain theranostics due to nano-sized delivery and its permeability which provided an improved and prolonged brain targeting of docetaxel and QDs in comparison to the non-targeted preparations.

The aim was to develop albumin anchored docetaxel lipid nanoemulsion (ALNE) for improving tumor targeted delivery. The O/W lipid nanoemulsion, LNEs were prepared by homogenization and ultrasonication processes. The size of globules and zeta potential were measured by Malvern Zetasizer. Albumin was coupled to stearylamine containing lipid nanoemulsion (SALNE) globules using water soluble EDC reaction. The drug content and entrapment efficiencies for the LNEs were determined by the high-performance liquid chromatography. The in vitro cytotoxic studies of the delivery systems were performed on MCF-7 and Hela cells. The IC 50 values of ALNE on both the cell lines were statistically significant. The in vivo antitumor activity was tested on solid tumors induced in C57BL/6 mice. This study revealed that the percentage tumor inhibition for the groups treated with DLNE, SALNE and ALNE when compared with untreated control was found to be 55.62 ± 5.41%, 54.27 ± 4.85% and 80.01 ± 2.74%, respectively. Furthermore, in vivo distribution studies were carried out in breast cancer MDA-MB231 xenografted Balb/c mice. The LNEs were loaded with fluorescent DiD oil and the distribution in different organs after 6 h was tracked using Caliper life sciences in vivo imaging system. The studies revealed that ALNE was superior in tumor targeting activity when compared with DLNE and SALNE by 3.04 and 2.26 folds, respectively. The average radiance values of ALNE on the tumor tissue were statistically significant when compared with DLNE, SALNE at p < 0.01. In addition, this strategy can become a platform technology for other lipophilic drugs to target tumors.

The purpose of this study is to synthesize a novel galactosylated cholesterol derivative, cholesterol-diethenyl decanedioate-lactitol (CHS-DD-LA) through lipase-catalyzed esterification in non-aqueous and to evaluate the preparation, pharmacokinetics and biodistribution of docetaxel (DOC) liposomes modified with CHS-DD-LA (G-DOC-L), which may actively gather at the liver compared with the conventional DOC liposomes (DOC-L) and commercial dosage form of DOC injection (DOC-i). A rapid and simple liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay was developed for the determination of the DOC concentration in plasma and tissues with Taxol as the internal standard (IS). To measure the liver-targeting effect of the G-DOC-L, relative uptake rate (Re), peak concentration ratio (Ce), targeting efficiency (Te) and relative targeting efficiency (RTe) were reduced as the evaluation parameters. The results showed that the entrapment efficiency, particle size and Zeta potential of G-DOC-L was 76.8 ± 3.5%, 95.6 nm and 27.19 mV, respectively. After i.v. administration at the dose of 2.5 mg/kg in rats, a decrease in the AUC, MRT and an increase in CL (p < 0.05) were observed in the G-DOC-L group compared with DOC-L. All these results suggested that galactose-anchored liposomes could rapidly be removed from the circulation in vivo. The tissue distribution of G-DOC-L was widely different from that of DOC-L. The Re of G-DOC-L, DOC-L on liver was 4.011, 0.102; Ce was 3.391, 0.111; Te was 55.01, 3.08, respectively, demonstrating that G-DOC-L had an excellent effect on liver-targeting, which may help to improve the therapeutic effect of hepatic diseases.

Context: Nanoemulsions (NE) are one of the robust delivery tools for drugs due to their higher stability and efficacy., Objectives: The purpose of present investigation is to develop stable, effective and safe NE of docetaxel (DTX)., Methods: Soybean oil, lecithin, Pluronic F68, PEG 4000 and ethanol were employed as excipients and NEs were prepared by hot homogenization followed by ultra-sonication. NEs were optimized and investigated for different in vitro and in vivo parameters viz. droplet size, poly dispersity index, charge; zeta potential, drug content and in vitro drug release, in vitro cytotoxicity, in vitro cell uptake and acute toxicity. Transmission electron microscopy was performed to study morphology and structure of NEs. Stability studies of the optimized formulation were performed., Results: Droplet size, poly dispersity index, zeta potential, drug content and in vitro drug release were found to be 233.23 ± 4.3 nm, 0.24 ± 0.010, -43.66 ± 1.9 mV, 96.76 ± 1.5%, 96.25 ± 2.1%, respectively. NE F11 exhibited higher cell uptake (2.83 times than control) and strong cytotoxic activity against MCF-7 cancer cells (IC50; 13.55 ± 0.21 µg/mL at 72 h) whereas no toxicity or necrosis was observed with liver and kidney tissues of mice at a dose of 20 mg/kg. Transmission electron microscopy ensured formation of poly-dispersed and spherical droplets in nanometer range. NE F11 (values indicated above) was selected as the optimized formulation based on the aforesaid parameters., Conclusion: Conclusively, stable, effective and safe NE was developed which might be used as an alternative DTX therapy.

Context: Docetaxel is now a major antitumor drug in clinical use for the treatment of a variety of tumors. The ethanol/Tween 80 solvent required in the formulation to increase the docetaxel solubility is at least partly responsible for the hypersensitivity reaction, decreased uptake by tumor tissue, and increased exposure to other body compartments., Objective: The present study was aimed at developing hydrosoluble DTX-FA-HSANPs targeting tumor cells and to investigate antitumor activities of the nanoparticles., Materials and Methods: The DTX-HSANPs were prepared using a desolvation technique and the carboxylic groups of NHS-folate were conjugated with the amino groups of the human serum albumin nanoparticles, and studied their size and zeta potential, drug loading efficiency, surface morphology, release properties in vitro, and antitumor activities., Results: The spherical nanoparticles obtained were negatively charged with a zeta potential of about -30 mV and characterized around 150 nm with a narrow size distribution. Drug loading efficiency was approximately 17.2%. The folate-decorated nanoparticles targeted a human hepatoma cell line effectively. The in vitro drug release of DTX-FA-HSANPs in the first 96 h corresponded with the following equation: Q = 18.87851 - 0.13866t + 0.21276t² - 0.00704t³ + 0.0000847854t⁴ - 0.00000034991t⁵ (R² = 0.98155). Moreover, the in vitro antitumor activities of DTX-FA-HSANPs were close to the activities of the positive control (docetaxel). The in vivo inhibition ratios of DTX-FA-HSANPs and docetaxel were 66.2% and 59.5%, respectively, at a dose of 5 mg/kg., Discussion and Conclusion: In light of the observed antitumor activities, it would be of considerable interest to collect sufficient data for the clinical application of docetaxel-loaded nanoparticles.

The taxanes are a class of chemotherapeutic agents that are widely used in the treatment of various solid tumors. Although taxanes are highly effective in cancer treatment, their use is associated with serious complications attributable to large interindividual variability in pharmacokinetics and a narrow therapeutic window. Unpredictable toxicity occurrence necessitates close patient monitoring while on therapy and adverse effects frequently require decreasing, delaying or even discontinuing taxane treatment. Currently, taxane dosing is based primarily on body surface area, ignoring other factors that are known to dictate variability in pharmacokinetics or outcome. This article discusses three potential strategies for individualizing taxane treatment based on patient information that can be collected before or during care. The clinical implementation of pharmacogenetics, enzyme probes or therapeutic drug monitoring could enable clinicians to personalize taxane treatment to enhance efficacy and/or limit toxicity.

Aim: Early markers of response to chemotherapy, measured by blood markers and imaging, may ultimately lead to tailored therapies that avoid cumulative toxicity., Materials & Methods: We performed a small pilot study to compare early changes in levels of circulatory tumor cells (CTCs) with changes in tumor proliferation, using metabolic imaging with [(18)F] 3´-deoxy-3´-fluorothymidine PET (FLT-PET) in women with advanced breast cancer, before and during docetaxel therapy., Results: In those individuals in whom we could detect CTCs, a decrease in CTC count correlated with a decrease in FLT-PET signal, within 2 weeks., Conclusion: Combined, these two technologies are likely to provide a powerful, albeit expensive, tool to assess immediate responses to therapy.

Among patients receiving adjuvant therapy for breast cancer, there is variability in treatment outcomes, and it is unclear which patients will receive the most benefit from treatment and which will have better disease-free survival. To date, most studies of breast cancer prognosis have focused on tumor characteristics, but it is likely that pharmacogenetics, genetic variability in the metabolism of therapeutic agents, also plays a role in the prediction of survival. In this paper, we briefly discuss the metabolic pathways of drugs commonly used for the treatment of breast cancer (cyclophosphamide, doxorubicin, taxanes, tamoxifen and aromatase inhibitors) and describe the known genetic variants that may impact those pathways. Studies that have evaluated potential effects of these genetic variants on treatment outcomes are also discussed. It is likely that the application of pharmacogenetics, particularly in the setting of randomized clinical trials, will contribute to findings that may result in individualized therapeutic dosing.

The spindle checkpoint monitors the fidelity of chromosome separation during mitosis. Aberrations in key regulators of this process have been found in human malignancies associated with chromosomal instability (CIN). Important chemotherapeutic agents which alter microtubule dynamics such as paclitaxel and vincristine, prolong spindle checkpoint activation and delay the completion of mitosis. Intriguingly, inhibition of BubR1 or overexpression of Aurora kinase A, spindle checkpoint regulators implicated in CIN, promote resistance to microtubule inhibitors (MTIs) in vitro. Taxanes have failed to demonstrate significant clinical benefit in phase II trials in colorectal cancer (CRC). The high incidence of CIN in this disease, coupled with alterations in spindle checkpoint regulators in vivo, may explain the disappointing results associated with taxane based therapies for CRC. A phase II trial of taxanes in patients with metastatic CIN negative CRC may be indicated.