经动脉药盒灌注治疗中晚期胰腺癌

目的评价经动脉药盒灌注盐酸吉西他滨、5-氟脲嘧啶（5-FU）和白细胞介素2（IL-2）对不同部位中晚期胰腺癌的治疗价值。方法回顾性分析63例不能手术切除的中晚期胰腺癌患者,经皮下动脉药盒系统灌注上述药治疗后不同部位胰腺癌的临床受益反应率（CBRR）和生存期。结果63例患者CBRR为44．4％,频数分布法计算中位生存期5．9个月,中位疾病进展期2．8个月。Kaplan-meier法计算6个月和9个月累积生存率分别为49．3％和26．8％。46例胰头癌患者和17例胰体尾癌患者6个月累积生存率分别为63．5％和40．6％,9个月分别为40．7％和12．3％。胰头癌患者和胰体尾癌患者CBRR分别为54．3％和17．6％（P〈0．01）,中位生存期分别为9．1个月和4．3个月。中位疾病进展期分别为3．5个月和2．1个月。结论经皮下动脉药盒系统灌注上述药对中晚期胰腺癌患者有较高的CBRR,可延长其生存期;胰头癌的疗效优于胰体尾部。     

Curcumin enhances the mitomycin C-induced cytotoxicity via downregulation of MKK1/2-ERK1/2-mediated Rad51 expression in non-small cell lung cancer cells

Curcumin (diferuloylmethane), a major active component of turmeric (Curcuma longa), has been reported to suppress the proliferation of a wide variety of tumor cells. Rad51 is a key protein in the homologous recombination (HR) pathway of DNA double-strand break repair, and HR represents a novel target for cancer therapy. A high expression of Rad51 has been reported in chemo- or radio-resistant carcinomas. Therefore, in the current study, we will examine whether curcumin could enhance the effects of mitomycin C (MMC), a DNA interstrand cross-linking agent, to induce cytotoxicity by decreasing Rad51 expression. Exposure of two human non-small lung cancer (NSCLC) cell lines (A549 and H1975) to curcumin could suppress MMC-induced MKK1/2-ERK1/2 signal activation and Rad51 protein expression. Enhancement of ERK1/2 activation by constitutively active MKK1/2 (MKK1/2-CA) increased Rad51 protein levels in curcumin and MMC co-treated human lung cells. Moreover, the synergistic cytotoxic effect induced by curcumin combined with MMC was decreased by MKK1-CA-mediated enhancement of ERK1/2 activation by a significant degree. In contrast, MKK1/2 inhibitor, U0126 was shown to augment the cytotoxicity of curcumin and MMC through downregulation of ERK1/2 activation and Rad51 expression. Depletion of endogenous Rad51 expression by siRad51 RNA transfection significantly enhanced MMC and/or curcumin induced cell death and cell growth inhibition. In contrast, an overexpression of Rad51 protected lung cancer cells from synergistic cytotoxic effects induced by curcumin and MMC. We concluded that Rad51 inhibition may be an additional action mechanism for enhancing the chemosensitization of MMC by curcumin in NSCLC.     

In vitro and in vivo evaluation of controlled-release and enteric-coated formulations of sodium salicylate

The bioavailability and pharmacokinetics of salicylic acid (SA) were studied after single and multiple doses of a new slow-release formulation, based on porous membrane diffusion of sodium salicylate (NaSA). A solution of NaSA and an enteric-coated tablet of NaSA were used for comparison. Dissolution rate studies were carried out at various pH values, and both solid formulations showed pH-dependent release rates. The entericcoated tablet released its content rapidly at intestinal pH but slowly and irregularly at gastric pH. The dissolution from the controlled-release formulation at intestinal pH was completed after 6 h and the drug was delivered at a constant rate. At gastric pH the release rate was lower but complete release was obtained within 24h. The novel formulation appeared to offer complete bioavailability of SA and an even and sustained release of SA, allowing twice-daily medication without increased fluctuations in SA concentrations.     

茶苯海明口腔崩解片及其普通片在恒河猴体内的药代动力学比较

目的：比较茶苯海明口腔崩解片及其普通片在恒河猴体内的药代动力学特征。方法：采用随机、自身对照方法考察两制剂在恒河猴体内的药代动力学特点;采用HPLC-UV法测定分别口服给予相应剂量的药物（均为茶苯海明50 mg）后恒河猴体内血药浓度;并采用DAS2.0对药代动力学参数进行统计分析。结果：茶苯海明口腔崩解片相对生物利用度（F0-12h,F0-∞）分别为（154±42）%和（150±53）%。两制剂间的血药浓度时间-曲线下面积（AUC0-∞）差异无统计学意义（P〉0.05）,而Cmax和AUC0-12差异有统计学意义（P〈0.05）。此外,茶苯海明口腔崩解片tmax与普通片比较明显缩短,但差异无统计学意义（P〉0.05）。茶苯海明在恒河猴空白血浆中10～2000 ng/mL浓度范围内线性良好（r=0.99995）,最低检测限（LLOQ）10 ng/mL。其他确证数据如准确度、精密度等均在要求范围内。结论：茶苯海明口腔崩解片在体内吸收比普通片快。     

Oral delivery of particulate prostate cancer vaccine: In vitro and in vivo evaluation

Background: Various approaches have been evaluated for generation of efficient immune response against tumor antigens. Our approach exploits usage of particulate delivery to generate immune response against prostate cancer antigens.

Purpose: The aim of this study was to evaluate the efficacy of prostate cancer vaccine derived from a murine prostate cancer cell line, TRAMP C2 in murine model via oral route using aleuria aurantia lectin as a targeting ligand for M-cells in the intestinal Peyer’s patches.

Methods: The whole cell lysate (WCL) was obtained from TRAMP C2 murine prostate cancer cell line and was formulated into particles using one step spray drying process. For in vivo studies, 4–6 week old C57BL/6 male mice were vaccinated orally biweekly for 10 weeks. Serum samples were analyzed at regular intervals to determine serum IgG levels. The mice were then challenged with live TRAMP C2 cells to determine efficacy of the vaccine.

Results: The serum IgG levels of vaccinated animals were higher compared to that of the controls. Moreover, the tumor growth was retarded significantly in the vaccinated mice compared to that of controls (p < 0.001).

Conclusions: The above findings suggest that oral particulate WCL vaccine can trigger an immune response against prostate cancer antigens.     

In vivo assessment of toxicity and pharmacokinetics of methylglyoxal. Augmentation of the curative effect of methylglyoxal on cancer-bearing mice by ascorbic acid and creatine

Previous in vivo studies from several laboratories had shown remarkable curative effect of methylglyoxal on cancer-bearing animals. In contrast, most of the recent in vitro studies have assigned a toxic role for methylglyoxal. The present study was initiated with the objective to resolve whether methylglyoxal is truly toxic in vivo and to reassess its therapeutic potential. Four species of animals, both rodent and non-rodent, were treated with different doses of methylglyoxal through oral, subcutaneous and intravenous routes. Acute (treatment for only 1 day) toxicity tests had been done with mouse and rat. These animals received 2, 1 and 0.3 g of methylglyoxal/kg of body weight in a day through oral, subcutaneous and intravenous routes respectively. Chronic (treatment for around a month) toxicity test had been done with mouse, rat, rabbit and dog. Mouse, rat and dog received 1, 0.3 and 0.1 g of methylglyoxal/kg of body weight in a day through oral, subcutaneous and intravenous routes respectively. Rabbit received 0.55, 0.3 and 0.1 g of methylglyoxal/kg of body weight in a day through oral, subcutaneous and intravenous routes respectively. It had been observed that methylglyoxal had no deleterious effect on the physical and behavioral pattern of the treated animals. Fertility and teratogenecity studies were done with rats that were subjected to chronic toxicity tests. It had been observed that these animals produced healthy litters indicating no damage of the reproductive systems as well as no deleterious effect on the offspring. Studies on several biochemical and hematological parameters of methylglyoxal-treated rats and dogs and histological studies of several organs of methylglyoxal-treated mouse were performed. These studies indicated that methylglyoxal had no apparent deleterious effect on some vital organs of these animals. A detailed pharmacokinetic study was done with mouse after oral administration of methylglyoxal. The effect of methylglyoxal alone and in combination with creatine and ascorbic acid on cancer-bearing animals had been investigated by measuring the increase in life span and tumor cell growth inhibition. The results indicated that anticancer effect of methylglyoxal was significantly augmented by ascorbic acid and further augmented by ascorbic acid and creatine. Nearly 80% of the animals treated with methylglyoxal plus ascorbic acid plus creatine were completely cured and devoid of any malignant cells within the peritoneal cavity.     

In vivo evaluation of the semi-simultaneous method for bioavailability estimation using controlled intravenous infusion as an 'extravascular' route of administration.

A recently proposed method for bioavailability estimation, called the semi-simultaneous method, was evaluated in vivo in rats using methysergide as a test substance. In this method the test and the reference dose are administered with a short time interval and a model including the bioavailability parameters is fitted to the concentration-time profile. In the present study, in order to control the true bioavailability, intravenous infusion was used to mimic extravascular administration and various input profiles were produced. Mono-, bi- and triexponential disposition functions with the true and also various erroneous input models were fitted to the individual data sets. The models were also fitted to truncated data sets to mimic a situation where a long duration of sampling is precluded. A combined fitting-deconvolution procedure was also applied. The simi-simultaneous method gave precise and accurate estimates of the bioavailability in most groups and a robustness in the estimate concerning the model fitted was noted. The true input model could be identified for all data sets using common goodness-of-fit criteria. In the groups where a 'flip-flop' situation was created (slower input than elimination) a poorer precision and accuracy and a higher sensitivity concerning the model fitted was observed. The model fitting and the fitting-deconvolution procedure generally gave very similar results.     

In vitro and in vivo evaluation of novel implantable collagen–chitosan–soybean phosphatidylcholine composite film for the sustained delivery of mitomycin C

An implantable mitomycin C (MMC) delivery system (MMC‐film), incorporating polylactide (PLA)–MMC nanoparticles in a composite film from blends of collagen–chitosan–soybean phosphatidylcholine (SPC) with a mass ratio of 4:1:1, was developed and evaluated. PLA–MMC nanoparticles were prepared using an improved emulsion/solvent evaporation technique and then dispersed uniformly within the film to result in a final MMC loading content of 0.8 mg/cm². Drug release studies were performed in pH 7.4 PBS at 37°C with drug analysis using UV/vis spectrometer at 366 nm. The MMC‐film exhibited more fractional drug release and a longer time to reach release equilibrium as compared with PLA‐MMC nanoparticles. In vivo, the MMC‐film was implanted at subcutaneous tumor sites of hepatoma‐bearing mice, and the curative effect was compared with those of drug‐free film. The growth of the tumors was dose‐dependently inhibited by MMC‐film. Histopathological analysis of specimens taken from tumor tissues harvested indicated that MMC‐film was lethal to hepatoma cells. Additionally, post mortem visual examination and microscopic images showed no sign of internal infection and fibrous encapsulation in any animals after 20 days of implantation of the MMC‐film or drug‐free film. It was concluded that the system provides great potential for local sustained delivery of MMC at the site of tumor or tumor resection for therapeutic purposes. Drug Dev Res 2009. © 2009 Wiley‐Liss, Inc.     

In vitro and in vivo evaluation of self-assembled chitosan nanoparticles selectively overcoming hepatocellular carcinoma via asialoglycoprotein receptor

Hepatocellular carcinoma (HCC) is one of the major causes of cancer-related mortality worldwide. Nowadays, liver-targeting drug delivery system has been proven as a promising strategy for overcoming HCC. Asialoglycoprotein receptor (ASGPR) is an ideal receptor for liver targeting, which is mainly expressed on hepatocytes. In this study, we developed several novel liver-targeting chitosan nanoparticles to selectively overcome HCC via ASGPR. Chitosan nanoparticles (Gly-CS-VE, Gal-Gly-CS-VE, Gly-CS-DCA, and Gal-Gly-CS-DCA) were prepared by grafting hydrophilic group (glycidol, Gly), hydrophobic group (deoxycholic acid, DCA or vitamin E succinate, VE), and ASGPR recognizing group (galactose, Gal). Subsequently, their characterizations were measured by ¹H NMR, FT-IR, TEM, and DLS. Doxorubicin (DOX) was loaded in nanoparticles and released out in a pH-dependent manner. Most importantly, the galactosylated Gal-Gly-CS-VE and Gal-Gly-CS-DCA nanoparticles exhibited significantly stronger in vitro cell internalization, cytotoxicity, anti-migration capabilities and in vivo anticancer efficacies than the corresponding Gly-CS-VE and Gly-CS-DCA nanoparticles, as well as free DOX. Finally, the four chitosan nanoparticles exhibited good biocompatibility without causing any obvious histological damage to the major organs. Overall, the galactosylated chitosan nanoparticles were proven to be promising pharmaceutical formulations for selectively overcoming HCC, with great potential for clinical applications.     

In vivo evaluation of thiolated poly(acrylic acid) as a drug absorption modulator for MRP2 efflux pump substrates

Recently, several polymers have been reported to modulate drug absorption by inhibition of intestinal efflux pumps such as multidrug resistance proteins (MRPs) and P-glycoprotein (P-gp). The aim of the present study was to evaluate the efficiency of thiolated poly(acrylic acid) (PAA-Cys) to act as a drug absorption modulator for MRP2 efflux pump substrates in vivo, using sulforhodamine 101 as representative MRP2 substrate. In vitro, the permeation-enhancing effect of unmodified PAA and PAA₂₅₀-Cys_, displaying 580 μmol free thiol groups per gram polymer, was evaluated by using freshly excised rat intestinal mucosa mounted in Ussing-type chambers. In comparison to that of the buffer control, the sulforhodamine 101 transport in the presence of 0.5% unmodified PAA₂₅₀ and 0.5% (w/v) PAA₂₅₀-Cys was 1.3- and 4.0-fold improved, respectively. In vivo, sulforhodamine 101 solutions containing 4% (w/v) unmodified PAA₂₅₀ or 4% (w/v) thiolated PAA₂₅₀ were orally given to rats. The PAA₂₅₀-Cys solution increased the area under the plasma concentration-time curve (AUC_0-12) of sulforhodamine 101 3.8-fold in comparison to control and 2.2-fold in comparison to unmodified PAA₂₅₀. This in vivo study revealed that PAA₂₅₀-Cys significantly increased the oral bioavailability of MRP2 substrate sulforhodamine 101.     

In vitro and in vivo skin anti-aging evaluation of gel containing niosomes loaded with a semi-purified fraction containing gallic acid from Terminalia chebula galls

Context: The galls of Terminalia chebula Retz. (Combretaceae) frequently appear in many Thai Lanna medicinal plant recipes for promotion of longevity.

Objective: The objective of this study was to evaluate the skin anti-aging of gel containing niosomes loaded with a semi-purified fraction containing gallic acid from T. chebula galls.

Method: The semi-purified fraction containing phenolic compounds including gallic acid isolated from T. chebula galls loaded in non-elastic or elastic niosomes, and its developed gel, were evaluated for rabbit skin irritation by the closed patch test and skin anti-aging in human volunteers by measuring skin elasticity and roughness.

Results: Gel containing the fraction unloaded (SS) or loaded in non-elastic (SN) or elastic (SE) niosomes and gallic acid loaded in non-elastic (GN) or elastic (GE) niosomes showed no skin irritation, whereas the unloaded gallic acid (GS) gave the irritation in rabbit’s skin by the closed patch test. The % parameter changes of skin elastic recovery and skin elastic extension when applied with SN and SE gels were +28.73 and +32.57; ?21.25 and ?22.63%, respectively. SN and SE gel also showed a significant decrease of the maximum and average roughness values with the parameter changes of ?29.43 and ?32.38; ?39.47 and ?35.28%, respectively.

Conclusion: The semi-purified fraction loaded in niosomes indicated not only higher chemical stability of gallic acid containing in the fraction, but also more in vivo anti-aging activities than the unloaded fraction when incorporated in gel.     

In vitro evaluation of valproic acid as an inhibitor of human cytochrome P450 isoforms: preferential inhibition of cytochrome P450 2C9 (CYP2C9)

AIMS: To evaluate the potency and specificity of valproic acid as an inhibitor of the activity of different human CYP isoforms in liver microsomes. METHODS: Using pooled human liver microsomes, the effects of valproic acid on seven CYP isoform specific marker reactions were measured: phenacetin O-deethylase (CYP1A2), coumarin 7-hydroxylase (CYP2A6), tolbutamide hydroxylase (CYP2C9), S-mephenytoin 4'-hydroxylase (CYP2C19), dextromethorphan O-demethylase (CYP2D6), chlorzoxazone 6-hydroxylase (CYP2E1) and midazolam 1'-hydroxylase (CYP3A4). RESULTS: Valproic acid competitively inhibited CYP2C9 activity with a Ki value of 600 microM. In addition, valproic acid slightly inhibited CYP2C19 activity (Ki = 8553 microM, mixed inhibition) and CYP3A4 activity (Ki = 7975 microM, competitive inhibition). The inhibition of CYP2A6 activity by valproic acid was time-, concentration- and NADPH-dependent (KI = 9150 microM, Kinact=0.048 min(-1)), consistent with mechanism-based inhibition of CYP2A6. However, minimal inhibition of CYP1A2, CYP2D6 and CYP2E1 activities was observed. CONCLUSIONS: Valproic acid inhibits the activity of CYP2C9 at clinically relevant concentrations in human liver microsomes. Inhibition of CYP2C9 can explain some of the effects of valproic acid on the pharmacokinetics of other drugs, such as phenytoin. Co-administration of high doses of valproic acid with drugs that are primarily metabolized by CYP2C9 may result in significant drug interactions.