Drug-drug interaction between tacrolimus and caspofungin in Chinese kidney transplant patients with different CYP3A5 genotypes.

Background: The effect of drug-drug interaction between tacrolimus and caspofungin on the pharmacokinetics of tacrolimus in different CYP3A5 genotypes has not been reported in previous studies. Objectives: To investigate the effect of caspofungin on the blood concentration and dose of tacrolimus under different CYP3A5 genotypes. Design: We conducted a retrospective cohort study in The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital from January 2015 to December 2022. All kidney transplant patients were divided into the combination or non-combination group based on whether tacrolimus was combined with caspofungin or not. Patients were subdivided into CYP3A5 expressers (CYP3A5*1/*1 or CYP3A5*1/*3) and CYP3A5 non-expressers (CYP3A5*3/*3). Methods: Data from the combination and the non-combination groups were matched with propensity scores to reduce confounding by SPSS 22.0. A total of 200 kidney transplant patients receiving tacrolimus combined with caspofungin or not were enrolled in this study. Statistical analysis was conducted on the dose-corrected trough concentrations (C0/D) and dose requirements (D) of tacrolimus using independent sample two-sided t-test and nonparametric tests to investigate the impact on patients with different. Results: In this study, the C0/D values of tacrolimus were not significantly different between the combination and non-combination groups (p = 0.054). For CYP3A5 expressers, there was no significant difference in tacrolimus C0/D or D values between the combination and non-combination groups (p = 0.359; p = 0.851). In CYP3A5 nonexpressers, the C0/D values of tacrolimus were significantly lower in the combination than in the non-combination groups (p = 0.039), and the required daily dose of tacrolimus was increased by 11.11% in the combination group. Conclusion: Co-administration of caspofungin reduced tacrolimus blood levels and elevated the required daily dose of tacrolimus. In CYP3A5 non-expressers, co-administration of caspofungin had a significant effect on tacrolimus C0/D values. An approximate 10% increase in the weight-adjusted daily dose of tacrolimus in CYP3A5 non-expressers is recommended to ensure the safety of tacrolimus administration.

Differential drug interactions of caspofungin on tacrolimus in Chinese kidney transplant patients with different CYP3A5 genotypes Why was the study done? Currently, there have been studies reporting the effect of caspofungin on tacrolimus blood concentrations, but the conclusions are conflicting, and no study has focused on the effect of CYP3A5 genotypes on the drug-drug interaction. We explored a number of research questions: 1. Does caspofungin have an effect on the pharmacokinetics of the immunosuppressant tacrolimus? 2. How does CYP3A5*3, which affects tacrolimus metabolism significantly, affect tacrolimus blood concentration levels? 3. How should the dose of tacrolimus be adjusted when combined with caspofungin? What did the researchers do? By reviewing literature, we understood the problems related with the kidney transplant patients better, which led to the development of strict inclusion and exclusion criteria. The patients (from January 2015 to December 2022) were categorized into combination and non-combination groups according to whether they were co-administered with caspofungin or not. The results of the study were analyzed using SPSS 22.0. What did the researchers find? The study finally included 200 patients. We found no statistically significant differences in the dose-corrected trough concentrations (C₀/D) and dose requirements (D) of tacrolimus between the combination and non-combination groups. However, in patients with CYPA5*3/*3 genotype, tacrolimus C₀/D values were significantly lower in the combination group than in the non-combination group, and the required daily tacrolimus dose was increased. What do the findings mean? This study has found that co-administration of caspofungin in patients with CYP3A5*3/*3 genotype resulted in a significant decrease in the C₀/D value of tacrolimus, therefore, an appropriate increase in the daily dose of tacrolimus is recommended. The implication is that it is important and necessary to monitor the concentrations of tacrolimus and the CYP3A5 genotypes, and adjust the dose when combined or discontinuing with caspofungin in kidney transplant patients.

CYP3A5 Genotype-Dependent Drug-Drug Interaction Between Tacrolimus and Voriconazole in Chinese Kidney Transplant Patients.

BACKGROUND: The effect of drug-drug interaction (DDI) between tacrolimus and voriconazole on the pharmacokinetics of tacrolimus in different CYP3A5 genotypes has not been reported in previous studies. OBJECTIVE: The objective of this study was to investigate whether CYP3A5 genotype could influence tacrolimus-voriconazole DDI in Chinese kidney transplant patients. METHODS: All kidney transplant patients were divided into combination and non-combination groups based on whether tacrolimus was combined with or without voriconazole. Each group was subdivided into CYP3A5 expresser (CYP3A5*1/*1 or CYP3A5*1/*3) and CYP3A5 nonexpresser (CYP3A5*3/*3). A retrospective analysis compared tacrolimus dose (D)-corrected trough concentrations (C0) (C0/D) between combination and non-combination groups, respectively. Tacrolimus C0/D was also compared between CYP3A5 expresser and nonexpresser in both groups. RESULTS: The C0/D values of tacrolimus were significantly different between CYP3A5 expresser and nonexpresser in combination group (378.20 [219.38, 633.48] ng/mL/[mg/kg/d] vs 720.00 [595.35, 1681.50] ng/mL/[mg/kg/d], P = 0.0010). Either in CYP3A5 expresser or nonexpresser, we found a statistically significant difference in tacrolimus C0/D between combination and non-combination group (P < 0.0001). The increase in CYP3A5 nonexpresser was 1.38 times higher than that in CYP3A5 expresser (320.93% vs 232.19%). CONCLUSION AND RELEVANCE: The median C0/D values were 90.38% higher in kidney transplant recipients with CYP3A5*3/*3 genotype than in those with CYP3A5*1/*1 or CYP3A5*1/*3 genotype when treated with both tacrolimus and voriconazole. A CYP3A5 genotype-dependent DDI was found between tacrolimus and voriconazole. Therefore, personalized therapy accounting for CYP3A5 genotype detection and therapeutic drug monitoring is necessary for kidney transplant patients when treating with tacrolimus and voriconazole.

IONPs-Based Medical Imaging in Cancer Care: Moving Beyond Traditional Diagnosis and Therapeutic Assessment.

Cancer-related burden of morbidity and mortality is rapidly rising worldwide. Medical imaging plays an important role in every phase of cancer management, including diagnosis, staging, treatment planning and evaluation. Iron oxide nanoparticles (IONPs) could serve as contrast agents or labeling agents to enhance the identification and visualization of pathological tissues as well as target cells. Multimodal or multifunctional imaging can be easily acquired by modifying IONPs with other imaging agents or functional groups, allowing the accessibility of combined imaging techniques and providing more comprehensive information for cancer care. To date, IONPs-enhanced medical imaging has gained intensive application in early diagnosis, monitoring treatment as well as guiding radio-frequency ablation, sentinel lymph node dissection, radiotherapy and hyperthermia therapy. Besides, IONPs mediated imaging is also capable of promoting the development of anti-cancer nanomedicines through identifying patients potentially sensitive to nanotherapeutics. Based on versatile imaging modes and application fields, this review highlights and summarizes recent research advances of IONPs-based medical imaging in cancer management. Besides, currently existing challenges are also discussed to provide perspectives and advices for the future development of IONPs-based imaging in cancer management.

The effect of metformin on lung cancer risk and survival in patients with type 2 diabetes mellitus: A meta-analysis.

WHAT IS KNOWN AND OBJECTIVE: Metformin has received increasing attention owing to its potential protective effect against cancer. We aimed to summarize evidence regarding the association between metformin and the risk or survival in lung cancer patients with type 2 diabetes. METHODS: We selected observational studies examining the association between exposure to metformin and the risk or survival in lung cancer. Available publications were searched in PubMed, Cochrane Library, ScienceDirect, Wiley and SpringerLink databases. Meta-analysis was performed with hazard ratios (HRs) and 95% confidence intervals (95% CIs) as effect measures for risk or survival in lung cancer. RESULTS: Eighteen studies (eight on lung cancer risk and ten on lung cancer survival) were included. Metformin treatment was associated with decreased lung cancer incidence (HR 0.78; 95% CI 0.70-0.86) and increased lung cancer survival (HR 0.65; 95% CI 0.55-0.77). In the subgroup analysis by ethnicity, a significant protective effect of metformin use on lung cancer risk was observed among Asian patients (HR 0.66; 95% CI 0.56-0.76), but not in European patients. On the other hand, the protective effect of metformin use on lung cancer survival was observed in both Asian (HR 0.57; 95% CI 0.49-0.66) and non-Asian (HR 0.79; 95% CI 0.71-0.88) patients. In the subgroup analysis by histology, a protective effect of metformin on lung cancer survival was observed in both non-small-cell lung cancer (HR 0.68; 95% CI 0.54-0.84) and small-cell lung cancer (HR 0.52; 95% CI 0.39-0.69). Funnel plot showed that no significant publication bias existed. CONCLUSIONS: Our findings demonstrate that metformin is significantly associated with a decreased risk and increased survival in lung cancer.

Preparation, characterization and antimicrobial activity of inclusion complexes of Myristica fragrans Hott. essential oil in ß-cyclodextrins.

Inclusion complexes of essential oils with cyclodextrins are an effective way to improve stability and solubility, and turn liquid materials into easy to handle powders. In this work, an essential oil of Myristica fragrans Hott. (MFEO), already used in the food and cosmetics industries, was formulated with beta-cyclodextrins (ß-CD) using a co-precipitation method. The orthogonal array scheme was adapted for the optimization of preparation process. DSC and FT-IR spectroscopy analysis indicated the successful formation of MFEO/ß-CD inclusion complexes, which improved the thermal stability of MFEO. Furthermore, comparing the antimicrobial activity of MFEO/ß-CD inclusion complexes and free essential oil against Staphyloccocus aureus, Staphyloccocus epidermidis, Escherichia coli, Klebsiella pneumoniae, yeast Saccharomyces cerevisiae and Bacillus subtilis, it was found that the antimicrobial effect was enhanced after the formation of inclusion complexes. This study demonstrates the potential for the use of MFEO/ß-CD inclusion complexes in the treatment of bacterial infection.

Simultaneous determination of six components in commercial Roukou Wuwei pills using ultra-high-performance liquid chromatography with diode-array detector.

An efficient ultra-performance liquid chromatography with diode-array detector method was established for simultaneous determination of six active components in Roukou Wuwei pills, namely gallic acid, piperine, costundide, dehydrocostus lactone, isoalantolactone and alantolactone. Chromatographic separation of six components was successfully achieved on an Waters BEH C18 column (50 × 2.1 mm, 1.7 µm) with a mobile phase composed of acetonitrile and water using a gradient elution. Gallic acid and piperine were detected at 270 nm and 343 nm, respectively; while costundide, dehydrocostus lactone, isoalantolactone and alantolactone were simultaneously measured at 225 nm. All six calibration curves showed good linearity (R2 ≥ 0.9994) between the peak area of each component and corresponding concentration. Relative standard deviations for inter- and intra-day precisions were <0.45 and 0.77%, respectively. The mean recovery rates ranged from 96.72 to 102.2% with relative standard deviations <2.07%. The developed method was validated in terms of linearity, precision and accuracy and then successfully applied for the quality control of commercial Roukou Wuwei samples.

The suppressive effects of miR-508-5p on the odontogenic differentiation of human dental pulp stem cells by targeting glycoprotein non-metastatic melanomal protein B.

BACKGROUND: Although the involvement of glycoprotein non-metastatic melanomal protein B (GPNMB) in regulating the odontogenic differentiation of human dental pulp stem cells (hDPCs) has been identified, the underlying mechanisms are largely unknown. The purpose of this study is to investigate the effects of miR-508-5p on the GPNMB expression and the odontogenic differentiation of hDPCs. METHODS: In this study, hDPCs were isolated and identified by flow cytometric analysis. Based on bioinformatics analysis, dual luciferase reporter assay was performed to verify GPNMB acting as a target of miR-508-5p. The regulatory roles of miR-508-5p in odontogenetic differentiation of hDPCs were investigated through its inhibition or overexpression (miRNA mimics and miRNA inhibitors). qRT-PCR and Western blot analysis were used to detect the expression of odontogenetic marker genes and proteins. The assays of alkaline phosphatase (ALP) activity and Alizarin Red S staining were performed to evaluate the odontogenetic phenotype. RESULTS: We first found that the levels of miR-508-5p expression decreased gradually during odontogenesis of hDPCs, while the expressions of GPNMB were upregulated obviously. The suppressive effects of miR-508-5p on GPNMB were determined by oligonucleotide transfection in hDPCs and dual luciferase reporter assay in 293T cells. Subsequently, the significant inhibition of hDPC odontogenesis after the overexpression of miR-508-5p was observed, which is consistent with the decreased expression levels of several odontoblast-specific genes, such as dentin matrix protein 1 (DMP-1), dentin sialophosphoprotein (DSPP), and osteocalcin (OCN), as well as the decreased activity of ALP and weakened Alizarin Red S staining. Furthermore, ectopic expression of GPNMB (lacking 3'-UTR) rescued the effects of miR-508-5p on odontogenic differentiation. CONCLUSIONS: Our study demonstrated that miR-508-5p regulated the osteogenesis of hDPCs by targeting GPNMB and provided novel insight into the critical roles of microRNAs in hDPC differentiation.

5-Acetamido-1-(methoxybenzyl) isatin inhibits tumor cell proliferation, migration, and angiogenesis.

Indole and its derivatives are widely distributed in both animals and plants. Among its array of biological activities, the anti-tumor activity of indole has garnered much attention. Furthermore, the synthesis and activity of indole derivatives, including isatin, constitute a flourishing research topic. Previously, many isatin derivatives were synthesized by our group, and 5-acetamido-1-(methoxybenzyl) isatin was screened as a candidate anti-tumor agent. In this study, we found that 5-acetamido-1-(methoxybenzyl) isatin inhibited the proliferation of several tumor cell lines, especially the human leukemia cell line K562. Morphological observation suggested that 5-acetamido-1-(methoxybenzyl) isatin induced apoptosis and caused cell cycle arrest in K562 cells. Flow cytometry revealed that 5-acetamido-1-(methoxybenzyl) isatin induced mitochondrial pathway-mediated apoptosis in K562 cells. Moreover, it downregulated Cyclin B and CDC25C and upregulated p-CDC25C and p-CDK1 (Thr14), and induced K562 cell cycle arrest in the G2/M phase. Findings from wound healing as well as transwell assay determined that 5-acetamido-1-(methoxybenzyl) isatin could suppress migration and chemotaxis in HepG2 liver cancer cells. 5-Acetamido-1-(methoxybenzyl) isatin also inhibited angiogenesis of the human umbilical vein endothelial cell line HUVEC, determined via a cell tube formation study. A clone formation study indicated that 5-acetamido-1-(methoxybenzyl) isatin can inhibit tumor cell proliferation and population dependence in a concentration-dependent manner. Thus, our findings support that 5-acetamido-1-(methoxybenzyl) isatin could be used as a potential antitumor candidate in future investigations.

Expression and Significance of TRIM 28 in Squamous Carcinoma of Esophagus.

Tripartite motif-containing protein 28 (TRIM28) has been proved to accelerate cell proliferation and metastasis in a variety of human cancers. However, the role of TRIM28 in esophageal squamous cell carcinoma (ESCC) remains unclear. In this study, to compare the biological effect and significance of TRIM28 expression in ESCC, immunohistochemistry (streptavidin-perosidase, S-P) method was used firstly to examine the expression of TRIM28 in 136 cases of ESCC, 35 cases of high grade intraepithelial neoplasia (HGIN), 29 cases of low grade intraepithelial neoplasia (LGIN) and 37 cases of normal esophageal epithelium (NEE). Then the associations of TRIM28 expression with clinicopathological data and overall survival (OS) were also analyzed. Western blot was performed to evaluate TRIM28 protein in a total of 20 matched human ESCC and NEE tissues. Moreover, the localization of TRIM28 protein in ESCC and NEE tissues was also detected by immunofluorescence. TRIM28 protein was mainly distributed in the nucleus of ESCC. The expression of TRIM28 increased progressively from NEE to LGIN, to HGIN, and to ESCC, and it was also related to invasive depth, pTNM stage and lymph node metastasis in ESCC (P < 0.05). The results of western blot and immunofluorescence all showed that the relative expression of TRIM28 protein was markedly upregulated in ESCC compared with the NEE tissues (P < 0.01). However, prognostic analysis showed that TRIM28 may not be a prognostic factor of patients with ESCC. In conclusion, the overexpression of TRIM28 may play an important role for development and metastasis in ESCC.

Theranostic Polymeric Micelles for the Diagnosis and Treatment of Hepatocellular Carcinoma.

Theranostics, which combine molecular imaging (diagnostics) and drug delivery (therapeutics) in a single platform, have recently shown great potential in cancer therapy. In this article, a polymeric micelle was designed and prepared for simultaneous magnetic resonance imaging (MRI) and treatment of hepatocellular carcinoma (HCC). Theranostic micelles were assembled using Poly(lactic acid)-poly(ethylene glycol)-poly(L-lysine)-diethylenetriamine pentaacetic acid (PLA-PEG-PLL-DTPA) and PLA-PEG-PLL-Biotin. The HCC therapeutic paclitaxel (PTX) was encapsulated in the cores and Gd ions for imaging were chelated to the DTPA moieties. Biotinylated alpha-fetoprotein (AFP) antibodies were linked to the micelle surface by a biotin-avidin reaction to form targeted Gd/PTX-loaded micelles (TGPM). TGPM were of spherical or ellipsoidal shape with uniform particle size distribution (147.50 ± 4.71 nm), positive zeta potential (24.45 ± 1.04 mV), and high encapsulation efficiency (88.76 ± 1.64%) and drug loading (1.59 ± 0.06%). The cytotoxicity of TGPM in HepG2 cells was superior to that of Taxol or Gd/PTX-loaded micelles (GPM). In MRI tests in vitro, the T1 relaxivity of TGPM was 21.589 mM(-1) s(-1), 4.4 times higher than Magnevist (r1 = 4.8 mM(-1) s(-1)). In H22 tumor-bearing mice, TGPM significantly increased tumor imaging intensity (more than 3 times) and prolonged imaging time (from 1 to 6 h) compared to Magnevist. In vivo, TGPM exhibited higher anti-tumor efficiency than Taxol and GPM. These results indicate that TGPM has great potential in HCC theranostics.

[Effects of Jiji decoction on the cognitive function and oxidative stress in mice with vascular dementia induced by cerebral ischemia/reperfusion].

OBJECTIVE: To determine the effects of Jiji decoction (Traditional Chinese Medicine) on the cognitive function and oxidative stress in mice with vascular dementia (VD) induced by cerebral ischemia/reperfusion. METHODS: Thirty-two mice were randomly divided into nonnal group (n = 8), sham group (operation, but no cerebral ischemia/reperfusi6n, n = 8), model group (vascular dementia model induced by cerebral ischemia/reperfusion, n = 8), and Jiji decoction-treated group (vascular dementia model plus treatment with Jiji decoction, n = 8). Fourteen days of treatment after operation, the cognitive behavior was measured in step-through test, spatial probe test and platform test. Afterwards, to assess the levels of oxidative stress, the activity of superoxide dismutase(SOD) and content of malonaldehyde (MDA) in brain of these mice were measured. RESULTS: Data from step-through test indicated that the escaping latency of Jiji decoction-treated group was prolonged and the error counts were decreased significantly ( P <0.01) compared with those of model group. Data from spatial probe test indicated that the time of entering darkroom, the time of climbing height and the time of entering bright room in Jiji decoction-treated group were shortened and the counts of climbing height were increased (P < 0.05-0.01) significantly compared with those of model group. Data from platform test showed that the escaping latency of Jiji decoction-treated group was prolonged significantly (P < 0.01) compared with that of model group. Compared with normal and sham group, the activity of SOD was decreased and the content of MDA was increased in model group significantly (P < 0.01). Compared with those of model group, the levels of SOD and MDA in Jiji decoction-treated group were improved significantly (P < 0.01). CONCLUSION: Jiji decoction could improve cognitive function of VD mice. Its mechanism might be related with the inhibition of oxidative stiess in the brain.

Polymeric complex micelles with double drug-loading strategies for folate-mediated paclitaxel delivery.

Drug loading is a key procedure in the preparation of drug-loaded nano-carriers. In this study, the paclitaxel (PTX)-loaded polymeric complex micelles (FA-P123-PTX/PTX micelles) with double drug-loading strategies were designed and prepared to improve the drug loading percentage of carriers and its anti-tumor efficiency. PTX was simultaneously conjugated to pluronic P123 (P123) polymer and encapsulated inside the P123 complex micelle. Folate (FA) was linked to the surface of micelles for the active target delivery of micelles to tumor cells. The FA-P123-PTX/PTX micelles showed spherical shaped with high drug loading of 18.08±0.64%. The results of cellular uptake studies suggested that FA could promote the internalization of micelles into the FR positive cells. FA-P123-PTX/PTX micelles showed significant higher anti-tumor activity against FR positive tumor cells compared to Taxol(®) (p<0.05). Moreover, the FA-P123-PTX/PTX micelles exhibited higher anti-tumor efficacy in B16 bearing mice with better safety property compared with Taxol(®). These results suggested that FA-P123-PTX/PTX micelles with double drug-loading strategies showed great potential for targeted delivery of anti-cancer drugs.

Polymer-polymer conjugation to fabricate multi-block polymer as novel drug carriers: poly(lactic acid)-poly(ethylene glycol)-poly(L-lysine) to enhance paclitaxel target delivery.

Multifunctional nanoparticles assembled from multi-block polymers are now one of the most convenient and convincing carriers for target drug delivery. Multi-block polymers could provide multi-functions such as sufficient drug loading capability and efficient target ligand coupling potency. In this article, novel multi-block polymer poly(lactic acid)-poly(ethylene glycol)-poly(L-lysine) (PLA-PEG-PLL) with relatively precise block molecular weight were synthesized by new method which we called polymer-polymer conjugation. This method conjugated different polymer blocks by reactions between the terminal active groups of different blocks, thus simplified the synthesis procedure. The obtained PLA-PEG-PLL was characterized by 1H NMR and gel permeation chromatography. The controlled drug delivery capability and the target ligand coupling potency of PLA-PEG-PLL were verified using paclitaxel (PTX) as model drug and vascular endothelial growth factor (VEGF) antibody as target ligand. The PTX-loaded PLA-PEG-PLL nanoparticles (PNP) and VEGF antibody modified PTX-loaded PLA-PEG-PLL nanoparticles (VPNP) were prepared using solvent diffusion methods. The two nanoparticles showed spherical or ellipsoidal shapes with uniform particle size distribution (190.1 +/- 1.27 nm and 203.6 +/- 4.10 nm for PNP and VPNP, respectively) and positive zeta potential (23.76 +/- 0.72 mv and 20.76 +/- 0.34 mv for PNP and VPNP, respectively). The cellular cytotoxicity, cellular uptake, in vivo therapeutic effects of the two nanoparticles were investigated. Cytotoxicity of VPNP against HepG2 cells was superior to that of PNP and Taxol. The VPNP and PNP showed better antitumor efficacy in a murine model bearing H22 compared with Taxol and VPNP was the best. The study on cellular uptake indicated that the better antitumor efficacy of VPNP was attributed to the increased uptake of drug by tumor cells. These results demonstrated that PLA-PEG-PLL was a favorable multifunctional material for drug target delivery and polymer-polymer conjugation was a promising method to fabricate novel multi-block polymers.

Tumor-specific delivery and therapy by double-targeted DTX-CMCS-PEG-NGR conjugates.

PURPOSE: To synthesize and evaluate the antitumor efficacy of double-targeted docetaxel (DTX)-carboxymethyl chitosan (CMCS)-PEG-NGR (DTX-CPN) conjugates that could target to CD13 over-expressed tumor neovascular endothelium cells and tumor cells. METHODS: DTX was conjugated to CMCS via biodegradable linker and cNGR was applied to endow the conjugates with double targeting ability. The physiochemical properties and stability of this DTX-CPN conjugates were characterized. Cellular uptake study was carried out to evaluate the targeting ability of DTX-CPN conjugates. Cytotoxicity and apoptosis analysis were conducted to evaluate in vitro antitumor effects. In vivo antitumor efficacy was investigated in B16 murine melanoma model. RESULTS: DTX-CPN conjugates could self-assemble into nanoparticles in water and were stable in plasma. cNGR modification could promote the cellular uptake of DTX-CPN conjugates in CD13 positive HUVEC and B16 cells, leading to more significant cytotoxicity and apoptosis effect than non-targeted conjugates. DTX-CPN conjugates also exhibited better antitumor effect than non-targeted conjugates and Duopafei® in a B16 murine melanoma model. CONCLUSIONS: Double-targeted DTX-CPN conjugates could efficiently target to tumor neovascular cells and tumor cells, and achieve good antitumor effects. DTX-CPN conjugates may be promising candidate for one-double targeting cancer therapy.

PH-sensitive self-assembled carboxymethyl chitosan-modified DNA/polyethylenimine complexes for efficient gene delivery.

In this study, DNA/polyethylenimine/carboxymethy chitosan ternary complexes (DPCs) were developed as a pH-sensitive gene delivery system via a layer-by-layer self-assembly technique. The DPCs assumed an obvious layered structure and showed good DNA-condensation ability. The result of a DNase I protection assay indicated that DPCs could effectively protect DNA from being degraded by nucleases. Compared with DNA/polyethylenimine binary complexes (DPs), DPCs showed better stability in plasma and lower cytotoxicity and acute toxicity due to carboxymethyl chitosan (CMCS) modification. The results of a pH-sensitive experiment confirmed that the outermost CMCS layer of the DPCs could peel off in an acidic environment (pH 6.5) due to the pH sensitivity of CMCS. In vitro transfection results showed that DPCs have good transfection ability under conditions that mimicked a tumor's pH environment, which also indicated that CMCS could detach from the DPCs in response to the acidic environment of tumor tissue. These results showed that CMCS modification could endow DPCs with good stability and low toxicity without inhibiting transfection efficiency. In conclusion, DPCs have the advantages of long circulation, good safety, pH sensitivity and ease of construction, which might provide a promising approach for efficient gene delivery.

Design, synthesis and in vitro cytotoxicity evaluation of 5-(2-carboxyethenyl)isatin derivatives as anticancer agents.

Forty four di- or trisubstituted novel isatin derivatives were designed and synthesized in 5-6 steps in 25-45% overall yields. Their structures were confirmed by (1)H NMR and (13)C NMR as well as LC-MS. The anticancer activity of these new isatin derivatives against three human tumor cell lines, K562, HepG2 and HT-29, were evaluated by MTT assay in vitro. SAR studies suggested that the combination of 1-benzyl and 5-[trans-2-(methoxycarbonyl)ethen-1-yl] substitution greatly enhance their cytotoxic activity, whereas an intact carbonyl functionality on C-3 as present in the parent ring is required to such a potency. This study leads to the identification of two highly active molecules, compounds 2h (IC50=3 nM) and 2k (IC50=6 nM), against human leukemia K562 cells.

Synthesis, characterization and antitumor evaluation of CMCS-DTX conjugates as novel delivery platform for docetaxel.

The purpose of this study is to synthesis and evaluate the antitumor efficacy of a novel carboxymethyl chitosan-docetaxel (CMCS-DTX) conjugates and the availability of CMCS as the polymer material in polymer-drug conjugates development. Docetaxel (DTX) was attached to carboxymethyl chitosan (CMCS) via biodegradable linker for the first time and the weight percentage of DTX in the CMCS-DTX conjugates was up to 20%. The resulting CMCS-DTX conjugates could spontaneously self-assemble into nanoparticles in aqueous buffer, with uniform size of 127.2±3.58 nm and zeta potential of -25.65 mV. The stability test result showed that only 12.46% of DTX was released after incubation in plasma for 48 h, indicating good stability of CMCS-DTX conjugates in plasma. The results of in vitro cytotoxicity and Hoechst staining indicated that CMCS-DTX conjugates exhibited significant cytotoxicity against B16 and HepG2 cells. CMCS-DTX conjugates also displayed better antitumor effect than Duopafei® by inhibiting tumor growth and prolonging the survival time of B16 melanoma bearing mice more effectively (the median survival time was >30 days for CMCS-DTX conjugates versus 24 days for the Duopafei®). Besides, CMCS-DTX conjugates demonstrated an excellent safety profile with a maximum tolerated dose (MTD) of >250 mg/kg in mice, which was more than 4 fold higher than that of Duopafei® (50 mg/kg). CMCS-DTX conjugates could be exploited as a promising platform for the effective delivery of DTX and CMCS was a favorable choice as the polymer material in polymer-drug conjugates development.

The targeted co-delivery of DNA and doxorubicin to tumor cells via multifunctional PEI-PEG based nanoparticles.

Co-delivery of nucleic acids and chemotherapeutics has a potential to efficaciously treat human diseases via their synergetic effects. Activable therapeutic tools at the nanoscale are suitable platforms for combination therapy. In this study, we have developed a multifunctional nanoscaled delivery system simultaneously integrated with passive and active tumor targeting, cell membrane translocation, pH-triggered drug release and co-delivery strategies. Poly (ethyleneimine) (PEI)-polyethylene glycol (PEG) copolymer was synthesized with coupling TAT to the distal end of PEG for membrane activity. The functional amino group of PEI was used to chemically conjugate doxorubicin (DOX) via a pH-sensitive hydrazone linkage. Meanwhile, the cationic PEI backbone could complex DNA to DOX loaded-TAT modified polyion complex micelles (NPIC). To achieve double targeting effect to tumor vascular endothelial cells and tumor cells either by active or passive targeting, a virus mimetic shell functioned with NGR was conferred by electrostatic adsorption of sulfamerazine (SA)-PEG-NGR on the surface of NPIC to obtain DOX loaded targeted PIC micelles (TPIC). The multifunctional nanoscaled delivery system was established to comprehensively improve the efficacy of cancer therapy through the synergistic effect of gene therapy with chemotherapy. Consequently, the system was shown to be a promising carrier for the co-delivery of DNA and DOX, leading to the efficiency of gene transfection and anti-tumor activity in vitro.

Tumor specific delivery and therapy by double-targeted nanostructured lipid carriers with anti-VEGFR-2 antibody.

Vascular endothelial growth factor receptors (VEGFRs) are overexpressed on the surface of a variety of tumor cells and on tumor neovasculature in situ, which are potential targets for "double targeting" (tumor- and vascular-targeting) tumor therapy. This study aimed to develop a VEGFR-mediated drug delivery system to target chemotherapeutic agents to VEGFR-overexpressed tumor cells and tumor neovasculature endothelial cells in vitro and in vivo. An antibody modified docetaxel (DTX)-loaded targeted nanostructured lipid carrier (tNLC) was designed and prepared with DSPE-PEG-NH(2) as linker. The cellular cytotoxicity, cellular uptake, in vivo therapeutic effect and biodistribution of tNLC were investigated. The tNLC showed a particle size about 168 nm with encapsulation efficiency >95%, drug loading 5.55 ± 0.06% (w/w) and an average ligand coupling efficiency of 3.34 ± 2.63%. Cytotoxicity of tNLC against three human cell lines and one murine malignant melanoma was superior to that of Duopafei and nontargeted NLC (nNLC). The tNLC also showed better tolerance and antitumor efficacy in a murine model bearing B16 compared with Duopafei or nNLC. The studies on cellular uptake and biodistribution indicated that the better antitumor efficacy of tNLC was attributed to the increased accumulation of drug in both tumor and tumor vasculature. These findings suggested that tNLC designed to bind specifically to VEGFR-2 can be used to deliver DTX to the tumor vasculature and tumor and may inhibit tumor growth.