Stem cell-nanomedicine system as a theranostic bio-gadolinium agent for targeted neutron capture cancer therapy.

The potential clinical application of gadolinium-neutron capture therapy (Gd-NCT) for glioblastoma multiforme (GBM) treatment has been compromised by the fast clearance and nonspecific biodistribution of gadolinium-based agents. We have developed a stem cell-nanoparticle system (SNS) to actively target GBM for advanced Gd-NCT by magnetizing umbilical cord mesenchymal stem cells (UMSCs) using gadodiamide-concealed magnetic nanoparticles (Gd-FPFNP). Nanoformulated gadodiamide shielded by a dense surface composed of fucoidan and polyvinyl alcohol demonstrates enhanced cellular association and biocompatibility in UMSCs. The SNS preserves the ability of UMSCs to actively penetrate the blood brain barrier and home to GBM and, when magnetically navigates by an external magnetic field, an 8-fold increase in tumor-to-blood ratio is achieved compared with clinical data. In an orthotopic GBM-bearing rat model, using a single dose of irradiation and an ultra-low gadolinium dose (200 µg kg-1), SNS significantly attenuates GBM progression without inducing safety issues, prolonging median survival 2.5-fold compared to free gadodiamide. The SNS is a cell-based delivery system that integrates the strengths of cell therapy and nanotechnology, which provides an alternative strategy for the treatment of brain diseases.

Lecithin-Stabilized Polymeric Micelles (LsbPMs) for Delivering Quercetin: Pharmacokinetic Studies and Therapeutic Effects of Quercetin Alone and in Combination with Doxorubicin.

In this study, lecithin-stabilized polymeric micelles (LsbPMs) were prepared to load quercetin (QUE) in order to improve its bioavailability and increase its antitumor activity. Its combination with doxorubicin (DOX) to minimize DOX-mediated cardiac toxicity and increase the antitumor activity of QUE-loaded LsbPMs was also examined. LsbPMs were prepared following a previously reported procedure. Results demonstrated that optimal QUE-loaded LsbPMs contained quercetin, D-α-tocopheryl polyethylene glycol succinate, and lecithin at a weight ratio of 6:40:80. Drug-release studies showed that QUE released from LsbPMs followed a controlled release pattern. A cytotoxicity assay revealed that QUE-loaded LsbPMs had significant anticancer activities against MCF-7, SKBR-3, and MDA-MB-231 human breast cancer cells and CT26 mouse colon cancer cells. In animal studies, intravenous administration of QUE-loaded LsbPMs resulted in efficient growth inhibition of CT26 colon cancer cells in a Balb/c mice model. In a pharmacokinetics study compared to free QUE, intravenous and oral administration of QUE-loaded LsbPMs was found to have significantly increased the relative bioavailability to 158% and 360%, respectively, and the absolute bioavailability to 5.13%. The effect of QUE-loaded LsbPMs in combination with DOX resulted in efficient growth inhibition of CT26 colon cancer cells and reduced cardiac toxicity in the Balb/c mice model.

Bispecific antibodies (anti-mPEG/anti-HER2) for active tumor targeting of docetaxel (DTX)-loaded mPEGylated nanocarriers to enhance the chemotherapeutic efficacy of HER2-overexpressing tumors.

Anti-mPEG/anti-human epidermal growth factor receptor 2 (HER2) bispecific antibodies (BsAbs) non-covalently bound to a docetaxel (DTX)-loaded mPEGylated lecithin-stabilized micellar drug delivery system (LsbMDDs) were endowed with active targetability to improve the chemotherapeutic efficacy of DTX. DTX-loaded mPEGylated LsbMDDs formulations were prepared using lecithin/DSPE-PEG(2K or 5K) nanosuspensions to hydrate the thin film, and then they were subjected to ultrasonication. Two BsAbs (anti-mPEG/anti-DNS or anti-HER2) were simply mixed with the LsbMDDs to form BsAbs-LsbMDDs formulations, respectively, referred as the DNS-LsbMDDs and HER2-LsbMDDs. Results demonstrated that the physical characteristics of the BsAbs-LsbMDDs were similar to those of the plain LsbMDDs but more slowly released DTX than that from the LsbMDDs. Results also showed that the HER2-LsbMDDs suppressed the growth of HER2-expressing MCF-7/HER2 tumors, increasing the amount taken up via an endocytosis pathway leading to high drug accumulation and longer retention in the tumor. In conclusion, the BsAbs-LsbMDDs preserved the physical properties of the LsbMDDs and actively targeted tumors with a drug cargo to enhance drug accumulation in tumors leading to greater antitumor activity against antigen-positive tumors.

Complex Hydrogels Composed of Chitosan with Ring-opened Polyvinyl Pyrrolidone as a Gastroretentive Drug Dosage Form to Enhance the Bioavailability of Bisphosphonates.

Complex hydrogels formed with chitosan (CS) and ring-opened polyvinyl pyrrolidone (roPVP) as a swellable mucoadhesive gastroretentive drug dosage form (smGRDDF) were prepared and characterized. CS/roPVP hydrogels were produced by blending CS with roPVP obtained by basic treatment of PVP. Effects of the heating time and NaOH concentration employed for preparing roPVP, and CS molecular weights (Mws), and roPVP/CS ratios on the swelling ability of the resultant hydrogels were characterized. Rheological characteristics were further examined. Results demonstrated that roPVP obtained in a 0.5 M NaOH solution heated to 50 °C for 4 h was suitable for producing complex hydrogels with CS. At a roPVP/CS ratio of 20:1, hydrogels composed of three different Mws of CS possessed optimal swelling and mucoadhesive abilities and rheological properties. In vitro dissolution revealed sustained drug release. A pharmacokinetic study exhibited that the plasma profile of alendronate followed a sustained manner with 3-fold enhancement of the oral bioavailability. In conclusion, the smGRDDF composed of CS/roPVP complex hydrogels was successfully developed and is potentially applicable to improve the clinical efficacy of bisphosphonates.

Novel application of pluronic lecithin organogels (PLOs) for local delivery of synergistic combination of docetaxel and cisplatin to improve therapeutic efficacy against ovarian cancer.

The synergistic combination of docetaxel (DTX) and cisplatin (CIS) by local drug delivery with a pluronic lecithin organogel (PLO) to facilitate high drug concentrations at tumor sites and less nonspecific distribution to normal organs is thought to be beneficial in chemotherapy. In this study, using Capryol-90 (C90) with the addition of lecithin as the oil phase was developed to carry DTX, which was then incorporated into a PLO-containing CIS to formulate a dual-drug injectable PLO for local delivery. An optimal PLO composite, P13L0.15O1.5, composed of PF127:lecithin:C90 at a 13:0.15:1.5 weight ratio was obtained. The sol-gel transition temperature of P13L0.15O1.5 was found to be 33 °C. Tumor inhibition studies illustrated that DTX/CIS-loaded P13L0.15O1.5 could efficiently suppress tumor growth by both intratumoral and peritumoral injections in SKOV-3 xenograft mouse model. Pharmacokinetic studies showed that subcutaneous administration of P13L0.15O1.5 was able to sustain the release of DTX and CIS leading to their slow absorption into the systemic circulation resulting in lower area under the plasma concentration curve at 0-72 h (AUC0-72) and maximum concentration (Cmax) values but longer half-life (T1/2) and mean residence time (MRT) values. An in vivo biodistribution study showed lower DTX and CIS concentrations in organs compared to other treatment groups after IT administration of the dual drug-loaded P13L0.15O1.5. It was concluded that the local co-delivery of DTX and CIS by PLOs may be a promising and effective platform for local anticancer drug delivery with minimal systemic toxicities.

Publisher Correction: Determination of total and unbound docetaxel in plasma by ultrafiltration and UPLC-MS/MS: application to pharmacokinetic studies.

A correction to this article has been published and is linked from the HTML version of this paper. The error has been fixed in the paper.

Development and characterization of docetaxel-loaded lecithin-stabilized micellar drug delivery system (LsbMDDs) for improving the therapeutic efficacy and reducing systemic toxicity.

In the present study, we attempted to develop a lecithin-stabilized micellar drug delivery system (LsbMDDs) for loading docetaxel (DTX) to enhance its therapeutic efficacy and minimize systemic toxicity. A novel DTX-loaded LsbMDDs was optimally prepared by a thin-film hydration method and then hydrated with a lecithin nanosuspension while being subjected to ultrasonication. Physical characteristics of the optimized DTX-loaded LsbMDDs formulations were examined and found to have a mean size of <200 nm, an encapsulation efficiency of >90%, and drug loading of >6% with stability at room temperature and at 4 °C being longer than 2 and 7 days, respectively. The in vitro release of DTX from the DTX-loaded LsbMDDs was slower than that from the generic product of DTX (Tynen®). A cell viability assay demonstrated that the LsbMDDs showed better cytotoxicity than Tynen® against CT26 cancer cells. The in vivo antitumor efficacy of the DTX-loaded LsbMDDs was observed to be better than that of Tynen® in a CT26 tumor-bearing mice model. A high-dose regimen of the DTX-loaded LsbMDDs formulation showed greater inhibition of DU145 tumor growth than did Tynen®, but with less to similar systemic toxicity. An in vivo study also showed that a greater amount of drug was able to accumulate in the tumor site with the DTX-loaded LsbMDDs, and its maximal tolerable doses for single and repeated injections were 2-2.5-fold higher than those of Tynen®. In conclusion, the LsbMDDs could be a promising high drug-loaded nanocarrier for delivering hydrophobic chemotherapeutic agents that can enhance the efficacy of chemotherapy and reduce systemic toxicity.

Determination of total and unbound docetaxel in plasma by ultrafiltration and UPLC-MS/MS: application to pharmacokinetic studies.

A sensitive and specific liquid chromatographic/tandem mass spectrometric (LC-MS/MS) method was developed and validated for quantifying total and unbound docetaxel drug concentrations in plasma. Calibration curves for unbound and total docetaxel were linear over the respective ranges of 0.108~10.8 and 0.54~216 ng/mL. The intra- and interday assay accuracy and precision did not exceed 15%. The methods were validated to show the standard range linearity, sensitivity, selectivity, accuracy, precision, and stability of docetaxel in the matrices tested. In addition, this method is fast and simple with a short run time of 4.5 min and a small plasma sample volume (500 µL). The validated method was successfully applied to a pharmacokinetic study of a docetaxel micelle formulation in rat plasma after intravenous administration at a dose of 10 mg/kg. Docetaxel micelles slowly released their drug payload, and protein-bound, unbound, and micellar drug pools existed simultaneously. These various forms in plasma pools were also measured in the study. We confirmed that most of the docetaxel in plasma was micelle-associated (96.52% at 24 h and 83.14% at 72 h) after micellar docetaxel administration, as a result of sequestration of the drug in long-circulating micelles.

Physical and Pharmacokinetic Characterizations of trans-Resveratrol (t-Rev) Encapsulated with Self-Assembling Lecithin-based Mixed Polymeric Micelles (saLMPMs).

This study involved physical and pharmacokinetic characterizations of trans-resveratrol (t-Rev)-loaded saLMPMs which attempted to improve t-Rev's pharmacokinetic profiles and bioavailability resolving hurdles limiting its potential health benefits. The optimal formulation consisted of t-Rev, lecithin, and Pluronic® P123 at 5:2:20 (t-Rev-loaded PP123 saLMPMs) provided mean particle size <200 nm, encapsulation efficiency >90%, and drug loading >15%. Compared to t-Rev solubilized with HP-ß-CD, t-Rev-loaded PP123 saLMPMs enhanced t-Rev's stability in PBS at RT, 4 °C, and 37 °C and in FBS at 37 °C, and retarded the in vitro release. Intravenous administration of t-Rev-loaded PP123 saLMPMs was able to enhance 40% absolute bioavailability and a greater portion of t-Rev was found to preferably distribute into peripheral compartment potentially establishing a therapeutic level at the targeted site. With oral administration, t-Rev-loaded LMPMs increases 2.17-fold absolute bioavailability and furnished a 3-h period of time in which the plasma concentration maintained above the desirable concentration for chemoprevention and accomplished a higher value of the dose-normalized area under the curve for potentially establishing an effective level at the target site. Therefore, intravenous and oral pharmacokinetic characteristics of t-Rev encapsulated with PP123 saLMPMs indicate that t-Rev can be translated into a clinically useful therapeutic agent.

Lysosomal acid phosphatase 2 is an unfavorable prognostic factor but is associated with better survival in stage II colorectal cancer patients receiving chemotherapy.

Colorectal cancer (CRC) is one of the leading cancers worldwide. Surgery is the main therapeutic modality for stage II CRC. However, the implementation of adjuvant chemotherapy remains controversial and is not universally applied so far. In this study, we found that the protein expression of lysosomal acid phosphatase 2 (ACP2) was increased in CRC and that stage II CRC patients with high ACP2 expression showed a poorer outcome than those with low ACP2 expression (p = 0.004). To investigate this discrepancy, we analyzed the relation between ACP2 expression and several clinical cofactors.Among patients who received chemotherapy, those with an high expression of ACP2 showed better survival in both stage II and III CRC than those with low ACP2 expression. In stage II CRC patients, univariate analysis showed ACP2 expression and T stage to be cofactors significantly associated with overall survival (ACP2: p = 0.006; T stage: p = 0.034). Multivariate Cox proportion hazard model analysis also revealed ACP2 to be an independent prognostic factor for overall survival (ACP2: p = 0.006; T stage: p = 0.041). Furthermore, ACP2-knockdown CRC cells showed an increase in chemoresistance to 5-FU treatment and increased proliferation marker in the ACP2 knockdown clone.Taken together, our results suggested that ACP2 is an unfavorable prognostic factor for stage II CRC and may serve as a potential chemotherapy-sensitive marker to help identify a subset of stage II and III CRC patients for whom chemotherapy would improve survival.Highlights1. To the best of our knowledge, the study is the first report to show ACP2 overexpression in human colorectal cancer (CRC) and its association with poor outcome in stage II CRC.2. Patients with stage II and III CRCs with high expression of ACP2 were more sensitive to chemotherapy than those with a low expression.3. ACP2 expression may serve as a marker for CRC patients receiving chemotherapy and help identify the subset of CRC patients who would benefit from chemotherapy.

Development and Characterization of Lecithin-based Self-assembling Mixed Polymeric Micellar (saMPMs) Drug Delivery Systems for Curcumin.

Self-assembling mixed polymeric micelles (saMPMs) were developed for overcoming major obstacles of poor bioavailability (BA) associated with curcumin delivery. Lecithin added was functioned to enlarge the hydrophobic core of MPMs providing greater solubilization capacity. Amphiphilic polymers (sodium deoxycholate [NaDOC], TPGS, CREMOPHOR, or a PLURONIC series) were examined for potentially self-assembling to form MPMs (saMPMs) with the addition of lecithin. Particle size, size distribution, encapsulation efficacy (E.E.), and drug loading (D.L.) of the mixed micelles were optimally studied for their influences on the physical stability and release of encapsulated drugs. Overall, curcumin:lecithin:NaDOC and curcumin:lecithin:PLURONIC P123 in ratios of 2:1:5 and 5:2:20, respectively, were optimally obtained with a particle size of < 200 nm, an E.E. of >80%, and a D.L. of >10%. The formulated system efficiently stabilized curcumin in phosphate-buffered saline (PBS) at room temperature or 4 °C and in fetal bovine serum or PBS at 37 °C and delayed the in vitro curcumin release. In vivo results further demonstrated that the slow release of curcumin from micelles and prolonged duration increased the curcumin BA followed oral and intravenous administrations in rats. Thus, lecithin-based saMPMs represent an effective curcumin delivery system, and enhancing BA of curcumin can enable its wide applications for treating human disorders.

Development and characterization of self-assembling lecithin-based mixed polymeric micelles containing quercetin in cancer treatment and an in vivo pharmacokinetic study.

Quercetin (Que) is known to have biological benefits including an anticancer effect, but low water solubility limits its clinical application. The aim of this study was to develop a lecithin-based mixed polymeric micelle (LMPM) delivery system to improve the solubility and bioavailability of Que. The optimal Que-LMPM, composed of Que, lecithin, Pluronic(®) P123, and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-methoxy[poly(ethylene glycol)-2000] in a proportion of 3:1:17.5:2.5 (w/w), was prepared by a thin-film method. The average size, polydispersion index, encapsulating efficiency, and drug loading of Que-LMPM were 61.60 ± 5.02 nm, 0.589 ± 0.198, 96.87% ± 9.04%, and 12.18% ± 1.11%, respectively. The solubility of Que in the Que-LMPM system increased to 5.81 mg/mL, compared to that of free Que in water of 0.17-7.7 µg/mL. The Que-LMPM system presented a sustained-release property in vitro. The in vitro cytotoxicity assay showed that the 50% inhibitory concentration values toward MCF-7 breast cancer cells for free Que, blank LMPMs, and Que-LMPMs were >200, >200, and 110 µM, respectively, indicating the nontoxicity of the LMPM carrier, but the LMPM formulation enhanced the cytotoxicity of Que against MCF-7 cells. A cellular uptake assay also confirmed the intake of Que-LMPM by MCF-7 cells. An in vivo pharmacokinetic study demonstrated that Que-LMPMs had higher area under the concentration-time curve and a longer half-life, leading to better bioavailability compared to a free Que injection. Due to their nanosize, core-shell structure, and solubilization potential, LMPMs were successfully developed as a drug delivery system for Que to improve its solubility and bioavailability.

Codelivery of doxorubicin-containing thermosensitive hydrogels incorporated with docetaxel-loaded mixed micelles enhances local cancer therapy.

Doxorubicin (DOX) thermosensitive hydrogels (TSHs) incorporated with docetaxel (DOC)-loaded mixed micelles were developed to co-deliver these two drugs through a TSH system, DH700kMF-13.5/M-DocLF, to improve local cancer therapy and reduce side effects. First, Pluronics-based DOC-loaded mixed micelles were developed and optimized. The optimal formulation designated as M-DocLF was composed of 1mg/g docetaxel, 15mg/g Pluronic F127 (PF127), and 45mg/g Pluronic L121 (PL121). Rheological tests showed that DH700kMF-13.5/M-DocLF was an injectable flowing solution, which formed a nonflowing gel at body temperature. After intratumoral (IT) or peritumoral (PT) administration, DH700kMF-13.5/M-DocLF demonstrated efficient growth inhibition of CT-26 tumors in a Balb/c mice model. The tumor inhibitory rate after IT administration of DH700kMF-13.5/M-DocLF was 92.4%, followed by 85.8%, 75.6%, 62.9%, 50.6%, and 49.5% for DH700kMF-15, free DOX, F-13.5/M-DocLF, Tynen (DOC solution), and M-DocLF, respectively. Furthermore, PT administration of DH700kMF-13.5/M-DocLF resulted in similar efficacies. Pharmacokinetic and biodistribution studies showed that after subcutaneous (SC) and IT administration of the designated formulations, smaller amounts of DOX and DOC were absorbed from the local SC or tumor sites into systemic circulation, probably reducing their systemic toxicity. Tumor retention of DOX and DOC in biodistribution studies further revealed that co-delivery of these two drugs in DH700KMF-13.5/M-DocLF potentially enhanced the efficacy of tumor inhibition. In conclusion, our in situ injectable DOX and DOC TSH is a potential dual drug delivery system, which can enhance the efficacy of cancer chemotherapy with minimal side effects and reduced chemoresistance.

Physical characterization and in vivo pharmacokinetic study of self-assembling amphotericin B-loaded lecithin-based mixed polymeric micelles.

To alleviate the inherent problems of amphotericin B (AmB), such as poor water solubility and nephrotoxicity, a novel self-assembling mixed polymeric micelle delivery system based on lecithin and combined with amphiphilic polymers, Pluronic(®), Kolliphor(®), d-alpha tocopheryl polyethylene glycol succinate, and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-methoxy(poly(ethylene glycol)-2000 (DSPE-PEG2K) was developed. An optimal formulation (Ambicelles) composed of AmB:lecithin:DSPE-PEG2K in a 1:1:10 weight ratio was obtained. The particle size, polydispersion index, drug encapsulation efficiency, and drug loading were 187.20±10.55 nm, 0.51±0.017, 90.14%, and 7.51%, respectively, and the solubility was increased from 0.001 to 5 mg/mL. Compared with that of Fungizone(®), the bioavailability of Ambicelles administered intravenously and orally increased 2.18- and 1.50-fold, respectively. Regarding the in vitro cytotoxicity, Ambicelles had a higher cell viability than free AmB solution or Fungizone(®) did. With pretreatment of 50 µg/mL ethanolic extract of Taiwanofungus camphoratus followed by AmB to HT29 colon cancer cells, the 50% inhibitory concentration of AmB solution was 12 µg/mL, whereas that of Ambicelles was 1 µg/mL, indicating that Ambicelles exerted a greater synergistic anticancer effect.

Protein subcellular localization prediction based on compartment-specific biological features.

Prediction of subcellular localization of proteins is important for genome annotation, protein function prediction, and drug discovery. We present a prediction method for Gram-negative bacteria that uses ten one-versus-one support vector machine (SVM) classifiers, where compartment-specific biological features are selected as input to each SVM classifier. The final prediction of localization sites is determined by integrating the results from ten binary classifiers using a combination of majority votes and a probabilistic method. The overall accuracy reaches 91.4%, which is 1.6% better than the state-of-the-art system, in a ten-fold cross-validation evaluation on a benchmark data set. We demonstrate that feature selection guided by biological knowledge and insights in one-versus-one SVM classifiers can lead to a significant improvement in the prediction performance. Our model is also used to produce highly accurate prediction of 92.8% overall accuracy for proteins of dual localizations.