Physalin B induces G2/M cell cycle arrest and apoptosis in A549 human non-small-cell lung cancer cells by altering mitochondrial function.

Physalin B (PB) is one of the major constituents of Physalis alkekengi var. franchetii, a well-known Chinese traditional herb. In this study, we demonstrated for the first time that PB exhibits significant antiproliferative and apoptotic activity in A549 human lung cancer cells in a concentration-dependent and time-dependent manner. Flow cytometric analyses indicated that PB-induced G2/M arrest through down-regulation of cyclin B1 and cell division control protein cyclin-dependent kinase 1, and up-regulation of p21. The reduction in the level of cyclin B1/cyclin-dependent kinase 1 complex down-regulated oxidative phosphorylation multisubunit activity to reduce mitochondrial energetic homeostasis. Moreover, defects in mitochondrial ATP synthesis and mitochondrial membrane potential were found in PB-treated cell lines. These abnormalities led to an increase in intracellular superoxide and apoptosis. Thus, as an inhibitor of mitochondrial energetic homeostasis, PB demonstrates potent antitumor activities and may be developed as an alternative therapeutic agent against non-small-cell lung cancer.

Development of a simple LC-MS/MS method for the determination of febuxostat in human plasma and its application to a bioequivalence study.

The purpose of this study was to design a simple, sensitive and rapid liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for a febuxostat bioequivalence study in healthy Chinese male volunteers. In this method, febuxostat and etodolac (internal standard) were isolated from plasma samples by protein precipitation with acetonitrile. The supernatant was chromatographed on a Zorbax SB-C18 (150 x 3.0 mm, 3.5-microm particle size, Agilent) column with a SecurityGuard Inertsil Symmetry C18 column (12.5 x 4.6 mm, 5-microm particle size, Waters). The lower limit of quantification for febuxostat in 0.2 mL of human plasma was 13.40 ng x mL(-1), and the linearity was achieved over a concentration range from 13.40 to 21440 ng x mL(-1). Febuxostat tablets from Hengrui Medicine Co., Ltd (test, Jiangsu, China) and from Takeda pharmaceuticals america, Inc. (reference, Deerfield, IL) were evaluated following a single 80 mg oral dose to 18 healthy volunteers. Bioequivalence was determined by calculating 90% confidence intervals (90% CI) for the ratio of C(max), AUC(0-t), and AUC(0-infinity) values for the test and reference products, using logarithmic transformed data. The calculated 90% CIs for the ratio of C(max) (88.7-131.2%), AUC(0-t) (99.2-122.7%) and AUC(0-infinity) (99.5-123.1%) values for the test and reference products were all located within the bioequivalence criteria range (80-125% for AUC, and 70-143% for Ca(mzax)), proposed by State of Food and Drug Administration [SFDA, 2005. China]. It was concluded that the two febuxostat formulations (test and reference) analyzed were bioequivalent in terms of rate and extent of absorption and the method met the principle of quick and easy clinical analysis.

Relative bioavailability and pharmacokinetic comparison of two different enteric formulations of omeprazole.

In order to comply with the requirements for a drug listed in China, the study was developed to compare the pharmacokinetics and relative bioavailability of two different enteric formulations of omeprazole (OPZ) in healthy Chinese subjects. A total of 32 volunteers participated in the study. Plasma concentrations were analyzed by nonstereospecific liquid chromatography/tandem mass spectrometric (LC-MS/MS) method. After administration of a single 40-mg dose of the two OPZ formulations, the comparative bioavailability was assessed by calculating individual AUC(0‒t) (the area under the concentration-time curve from time zero to the last measurable concentration), AUC(0‒∞) (the area under the concentration-time curve extrapolated to infinity), C(max) (the maximum observed concentration), and T(peak) (the time to C(max)) values of OPZ, 5-hydroxyomeprazole (OH-OPZ), and omeprazole sulfone (OPZ-SFN), respectively. The 90% confidence intervals (CIs) of AUC(0‒t), AUC(0‒∞), and C(max) were 85.4%‒99.0%/88.8%‒98.6%/87.6%‒99.4%, 85.5%‒99.2%/89.0%‒98.6%/88.5%‒101.3%, and 72.3%‒87.6%/79.6%‒91.1%/88.4%‒99.1% for OPZ/OH-OPZ/OPZ-SFN, respectively, and T(peak) values did not differ significantly. In this study, the test formulation of OPZ in fasting healthy Chinese male volunteers met the Chinese bioequivalance standard to the reference formulation based on AUC, C(max), and T(peak).

RRM1 and ERCC1 expression in peripheral blood versus tumor tissue in gemcitabine/carboplatin-treated advanced non-small cell lung cancer.

PURPOSE: To comparatively evaluate the prognostic or predictive value of ribonucleotide reductase M1 (RRM1) and excision repair cross-complementation 1 (ERCC1) gene expression in peripheral blood versus tumor tissue from patients with advanced non-small cell lung cancer (NSCLC) treated by gemcitabine/platinum chemotherapy. METHODS: A total of 49 patients with advanced NSCLC receiving gemcitabine plus carboplatin chemotherapy were studied. RRM1 and ERCC1 mRNA levels in the peripheral blood and tumor tissue were determined by real-time fluorescent quantitative PCR. The relationships between gene expression and clinical and pathological factors, response to chemotherapy as well as prognosis, were evaluated. RESULTS: RRM1 expression in peripheral blood and tumor tissue, but not ERCC1 expression, was found to be positively correlated (r = 0.332, 0.258; P = 0.020, 0.073; respectively). RRM1 and ERCC1 expression levels were nearly synchronous in both peripheral blood (r = 0.351; P = 0.013) and tumor tissue (r = 0.634; P < 0.001). Neither was correlated with clinical and pathological factors. PATIENTS: with low RRM1 expression in peripheral blood or low RRM1 or ERCC1 expression in tumor tissue experienced better response to chemotherapy (50.0 vs. 16.0%, 50.0 vs. 16.0%, and 54.2 vs. 12.0%; P = 0.012, 0.012, and 0.003; respectively), longer median survival (18.5 vs. 13.0 months, 18.5 vs. 12.0 months, and 19.8 vs. 12.5 months; P = 0.043, 0.014 and 0.007; respectively), and longer progression-free survival (6.0 vs. 4.0 months, 7.8 vs. 3.9 months, and 5.8 vs. 3.8 months; P = 0.044, 0.016, and 0.008; respectively). Cox multivariate regression analysis showed that ERCC1 expression in tumor tissue was independent indicator for overall survival. CONCLUSIONS: Advanced NSCLC patients with low RRM1 mRNA expression both in peripheral blood and in tumor tissue could benefit from gemcitabine/carboplatin chemotherapy. ERCC1 mRNA expression in tumor tissue may be a predictive and prognostic indicator in advanced NSCLC patients receiving gemcitabine/carboplatin chemotherapy.

[Clinical study of single-dose of recombinant humanized anti-CD3 monoclonal antibody injection in kidney transplant recipients].

OBJECTIVE: To evaluate short-term and long-term safety of using single-dose escalation of recombinant humanized anti-CD3 monoclonal antibody (OKT3) in kidney transplantation recipients. METHODS: A total of 29 recipients of cadaveric kidney transplant from June 2008 to December 2008 were sequently assigned to receive single-dose intravenous injection of OKT3 with different doses of 2.5 mg (n = 9), 5.0 mg (n = 10) and 10.0 mg (n = 10) at Days 7 - 14 post-operation. Meanwhile, a control group was established by selecting kidney transplant recipients, who did not participate in the trial in the same period. All patients were followed up for at least 2 years. During this period, liver function, kidney function, hemoglobin and other biochemical indicators were monitored and adverse events recorded over time. RESULTS: No obvious first dose effect was observed, except low heat (7/29), chills (4/29), mild liver damage (2/29), upper respiratory tract infection and headache (1/29) across all doses. Other adverse reactions were mild, unrelated with doses. The 2-year patients/grafts survival rates of treatment group and control group were 100%/100%, and 100%/97%, respectively. The incidence of acute rejection confirmed by renal biopsy was 6.9% (2/29) and 10.0% (3/30) in treatment group and control group, respectively. The incidence of lung infection was 10.3% (3/29) and 13.3% (4/30), respectively. The values of serum creatinine at 1 week and 3, 6, 12, 24 months showed no statistically significance in two groups (all P > 0.05). CONCLUSION: It is safe to use single-shot OKT3 intravenously in kidney transplant recipients. The recombinant humanized OKT3 may be an effective immunosuppressive agent with milder toxicity for solid organ transplantation.

Determination of lansoprazole in human plasma by rapid resolution liquid chromatography-electrospray tandem mass spectrometry: application to a bioequivalence study on Chinese volunteers.

A simple, sensitive and rapid LC/MS/MS method was developed for the quantification of lansoprazole in human plasma. After a simple sample preparation procedure by one-step protein precipitation with acetonitrile, lansoprazole and the internal standard bicalutamide were chromatographed on a Zorbax SB-C(18) (3.0 mm x 150 mm, 3.5 microm, Agilent) column with the mobile phase consisted of methanol-water (70:30, v/v, containing 5 mM ammonium formate, pH was adjusted to 7.85 by 1% ammonia solution). Detection was performed on a triple quadrupole tandem mass spectrometry by multiple reaction monitoring (MRM) mode via negative eletrospray ionization source (ESI(-)). The lower limit of quantification was 5.5 ng/mL, and the assay exhibited a linear range of 5.5-2200.0 ng/mL. The validated method was successfully applied to investigate the bioequivalence between two kinds of preparation (test vs. reference product) in twenty-eight healthy male Chinese volunteers.

Determination of risperidone in human plasma by HPLC-MS/MS and its application to a pharmacokinetic study in Chinese volunteers.

This study presents a rapid, specific and sensitive liquid chromatography/tandem mass spectrometry (LC-MS/MS) assay for determination of risperidone (RIS) in human serum using paroxetine as an internal standard (IS). An Alltima-C18 column (2.1 mmx100 mm, 3 microm) and a mobile phase consisting of 0.1% formic acid-acetonitrile (40:60, v/v) were used for separation. The analysis was performed by selected reaction monitoring (SRM) method, and the peak area of the m/z 411.3-->191.1 transition for RIS was measured versus that of the m/z 330.1-->192.1 transition for IS to generate the standard curves. The assay linearity of RIS was confirmed over the range 0.25 approximately 50.00 ng/ml and the limit of quantitation was 0.05 ng/ml. The linear range corresponds well with the serum concentrations of the analytes obtained in clinical pharmacokinetic studies. Intraday and interday relative standard deviations were 1.85% approximately 9.09% and 1.56% approximately 4.38%, respectively. The recovery of RIS from serum was in the range of 70.20% approximately 84.50%. The method was successfully applied to investigate the bioequivalence between two kinds of tablets (test versus reference products) in 18 healthy male Chinese volunteers. The result suggests that two formulations are bioequivalent.

Pharmacokinetics of gemcitabine in Chinese patients with non-small-cell lung cancer.

To determine the pharmacokinetics of gemcitabine (2',2'-difluorodeoxycytidine) in Chinese non-small-cell lung cancer (NSCLC) patients. Six study subjects were administered gemcitabine at a fixed dose rate of 10 mg/m(2) per min (1200 mg/m(2), two hours infusion), and carboplatin and plasma gemcitabine concentrations were measured by ion-pair reversed-phase high-performance liquid chromatography (HPLC). 3P97 Pharmaceutical Kinetics Software was used for the calculation of pharmacokinetic parameters. The obtained mean parameters, elimination half life (t(1/2)) (10.67+/-3.38 min), area under the curve (AUC) (7.55+/-1.53 (microg x h)/ml), and clearance (CL) (3940.05+/-672.08 ml/min), were consistent with those reported in literature. The hematologic toxicology result showed that the regimen was effective on and tolerated by the patients.