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Ji A.-J.,Nanjing University | Liu S.-L.,Jiangsu Provincial Hospital of Traditional Chinese Medicine | Ju W.-Z.,Clinical Pharmacology Laboratory | Huang X.-E.,Nanjing Medical University
Asian Pacific Journal of Cancer Prevention | Year: 2014

Aim: To investigate the effects of tetramethypyrazine (TMP) on proliferation and apoptosis of the human gastric carcinoma cell line 7901 and its possible mechanism of action. Methods: The viability of TMP-treated 7901 cells was measured with a 3-(4, 5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT) and cell apoptosis was analyzed by flow cytometry. The distribution of cells in different phases of cell cycle after exposure of TMPs was analyzed with flow cytometry. To investigate the molecular mechanisms of TMP-mediated apoptosis, the expression of NF-κBp65, cyclinD1 and p16 in SGC-7901 cells was analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and western blotting. Results: TMP inhibited the proliferation of human gastric carcinoma cell line 7901 in dose and time dependent manners. Cell growth was suppressed by TMP at different concentrations (0.25, 0.5, 1.0, 2.0 mg/ml), the inhibition rate is 0.46%, 4.36%, 14.8%, 76.1% (48h) and 15.5%, 18.5%, 41.2%, 89.8% (72h) respectively. When the concentration of TMPs was 2.0mg/ml, G1-phase arrest in the SGC-7901 cells was significant based on the data for cell cycle distribution. RT-PCR demonstrated that NF-κBp65 and cyclin D1 mRNA expression was significantly down-regulated in 7901 cells treated with 2.0 mg/ml TMP for 72h (p<0.05), while the p16 mRNA level was up-regulated (p<0.05). The protein expression of NF-κBp65 and cyclin D1 decreased gradually with the increase in TMP concentration, compared with control cells (p<0.05), while expression of protein p16 was up-regulated (p<0.01). Conclusion: TMP exhibits significant anti-proliferative and pro-apoptotic effects on the human gastric carcinoma cell line SGC-7901. NF-κBp65, cyclinD1 and p16 may also play important roles in the regulation mechanisms. Source


Lim W.-T.,National Cancer Center Singapore | Ng Q.-S.,National Cancer Center Singapore | Ivy P.,U.S. National Cancer Institute | Leong S.-S.,National Cancer Center Singapore | And 7 more authors.
Clinical Cancer Research | Year: 2011

Purpose: Nasopharyngeal carcinoma is endemic in Asia and angiogenesis is important for Growth and progression. We hypothesized that pazopanib would have antiangiogenic activity in nasopharyngeal carcinoma. Experimental Design: A single arm monotherapy study of pazopanib in patients with WHO type II/III nasopharyngeal carcinoma who had metastatic/recurrent disease and failed at least one line of chemotherapy. A Simon's optimal 2-stage design was used. Patients with Eastern Cooperative Oncology Group (ECOG) 0-2 and adequate organ function were treated with pazopanib 800 mg daily on a 21-day cycle. The primary endpoint was clinical benefit rate (CR/PR/SD) achieved after 12 weeks of treatment. Secondary endpoints included toxicity and progression-free survival. Exploratory studies of dynamic-contrast enhanced computed tomography (DCE-CT) paired with pharmacokinetics (PK) of pazopanib was done. Results: Thirty-three patients were accrued. Patients were ECOG 0-1 with median age of 50 years (range 36-68). There were 2 (6.1%) partial responses, 16 (48.5%) stable disease, 11 (33.3%) progressive disease, 4 (12.1%) were not evaluable for response. The clinical benefit rate was 54.5% (95% CI: 38.0-70.2). Ten patients (30.3%) received more than 6 cycles (4 months) of treatment and 7 (21.2%) had PR/SD that lasted at least 6 months. One patient each died from epistaxis and myocardial infarction. Common grade 3/4 toxicities included fatigue (15.2%), hand-foot syndrome (15.2%), anorexia (9.1%), diarrhea (6.1%), and vomiting (6.1%). Serial DCE-CT scans show significant reductions in tumor blood flow, permeability surface area product, and fractional intravascular blood volume. Conclusion: Pazopanib showed encouraging activity in heavily pretreated nasopharyngeal carcinoma with an acceptable toxicity profile. ©2011 AACR. Source


Ma Y.-C.,Clinical Pharmacology Laboratory | Su N.,Henan University | Shi X.-J.,Zhengzhou University | Zhao W.,Zhengzhou University | And 6 more authors.
Toxicology and Applied Pharmacology | Year: 2015

Jaridonin, a novel diterpenoid from Isodon rubescens, has been shown previously to inhibit proliferation of esophageal squamous cancer cells (ESCC) through G2/M phase cell cycle arrest. However, the involved mechanism is not fully understood. In this study, we found that the cell cycle arrest by Jaridonin was associated with the increased expression of phosphorylation of ATM at Ser1981 and Cdc2 at Tyr15. Jaridonin also resulted in enhanced phosphorylation of Cdc25C via the activation of checkpoint kinases Chk1 and Chk2, as well as in increased phospho-H2A.X (Ser139), which is known to be phosphorylated by ATM in response to DNA damage. Furthermore, Jaridonin-mediated alterations in cell cycle arrest were significantly attenuated in the presence of NAC, implicating the involvement of ROS in Jaridonin's effects. On the other hand, addition of ATM inhibitors reversed Jaridonin-related activation of ATM and Chk1/2 as well as phosphorylation of Cdc25C, Cdc2 and H2A.X and G2/M phase arrest. In conclusion, these findings identified that Jaridonin-induced cell cycle arrest in human esophageal cancer cells is associated with ROS-mediated activation of ATM-Chk1/2-Cdc25C pathway. © 2014 Elsevier Inc. Source


Sallustio B.C.,Clinical Pharmacology Laboratory | Sallustio B.C.,University of Adelaide | Noll B.D.,Clinical Pharmacology Laboratory | Morris R.G.,Clinical Pharmacology Laboratory | Morris R.G.,University of Adelaide
Clinical Biochemistry | Year: 2011

Objectives: An LC-MS/MS method was developed for simultaneous quantitation of tacrolimus, sirolimus and everolimus in whole blood, and compared to HPLC-UV and immunoassay methods. Design and methods: Blood (0.1. mL) was analysed following solid-phase extraction and chromatographic resolution using a C18 column (45 °C) and mobile phase of methanol/40. mM ammonium acetate/glacial acetic acid (83/17/0.1) at 200 μL/min, with positive electrospray ionisation and multiple reaction monitoring. Results: Intra- and inter-day imprecision and inaccuracy were ≤ 12.2% over a 1.5-40 μg/L calibration range. An external quality assurance programme confirmed acceptable inaccuracy and imprecision of the LC-MS/MS method, but highlighted problems with immunoassay quantitation, particularly for everolimus, showing a > 30% bias in FPIA everolimus concentrations measured in pooled patient samples versus spiked drug-free whole blood. Conclusions: LC-MS/MS provides significant accuracy and precision advantages compared to HPLC and immunoassays. Discrepancies in everolimus concentrations measured by the Seradyn FPIA immunoassay require further investigation. © 2010. Source


Ma Y.,Clinical Pharmacology Laboratory | Su N.,Clinical Pharmacology Laboratory | Zhao N.,Clinical Pharmacology Laboratory | Qin Y.,Clinical Pharmacology Laboratory | And 4 more authors.
Chinese Journal of Oncology | Year: 2015

Objective: The aim of this study was to explore the molecular mechanism of apoptosis in esophageal cancer cells induced by Isodon rubescens. Methods: The DNA-damage effect of Jaridonin was detected by single cell gel electrophoresis (SCGE). The p53 protein was determined by Western blot. GSH assay kit was employed to determine the GSH content in human esophageal cancer EC-1 cells. Intracellular levels of hydrogen peroxide ( H2O2) or superoxide ( O 2.-) were determined using the redox-sensitive probes 2',7'-dichlorodihydrofluorescein diacetate (DCF) or dihydroethidium ( DHK) , and the fluorescence signal was assayed by fluorescence microscopy and by flow cytometry. Results: Jaridonin induced DNA damage in EC-1 cells remarkably. The olive tail moments (OTM) of control and 20, 40 μrnol/L Jaridonin were 3.2, 45.2 and 89. 0, respectively. Compared with the control, the differences were significant ( P < 0. 01 for both). Jaridonin resulted in extensive p53 up-regulation in the EC-1 cells. More importantly, the p53 up-regulation occurred as early as 2 h after Jaridonin incubation, and in a time-dependent manner (P < 0.05). p53 siRNA transfection inhibited apoptosis in the EC-1 cells, and the Jaridonin-induced apoptosis rate was reduced from 38.5% to 8.8% . Intracellular level of H2O2 was increased by Jaridonin, whereas the level of O 2.- was barely changed. The GSH content in EC-1 cells was reduced from ( 10. 3 ± 1. 6) nmol/mg protein to (4.6 ±2. 1 ) nmol/mg protein after 20 μmol/L Jaridonin incubation for 8 h, and it was further reduced with the increase of Jaridonin concentration. Jaridonin induced DNA damage, H2O2 accumulation and apoptosis were significantly attenuated in the presence of GSH, but Jaridonin showed little effect on normal human liver L-02 cells. Conclusions : Jaridonin selectively induces apoptosis in esophageal cancer EC-1 cells through H2O2-mediated DNA damage by depleting GSH. Source

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