BACKGROUND AND AIM: To elucidate the effect of sesquiterpene lactones on the nuclear factor-kappa B (NF-κB) signal transduction regulation in human nasopharyngeal carcinoma (NPC) cells. MATERIALS AND METHODS: Parthenolide (PN) was used for treatment. Human CNE1 cell line was used to establish the cellular model after induction by TNF-α. The cytoplasmic and nuclear proteins were extracted after treatment by PN. The degradation of IκBα, the activation of p65 subunit and its nuclear translocation, and the DNA binding activity of nuclear activated NF-κB in EMSA assay were evaluated. RESULTS: In negative control group IκBα protein was expressed in the cytoplasm but not in nucleus. In the PN-pretreated group, however, the IκBα protein was increased in cytoplasm and decreased in nuclear protein. Meanwhile in PN-pretreated followed by TNF-α treatment cells, NF-κB p65 subunit level was increased in cytoplasm but was decreased in nuclei, when compared to non-PN-pretreated but TNF-α induction cells. Further EMSA analysis showed that NF-κB binding activity in PN-treated group was significantly lower than that in TNF-α-induced group. The alterations of intracellular NF-κB signal correlated with PN-pretreatment time (0.5－4 h) and in a dose-dependent (5－25 μmol/L) manner. CONCLUSION: PN inhibited the TNF-α-activated NF-κB signal transduction pathway in NPC cells. Such inhibitory effect may be one of the molecular mechanisms associated with the sensitization of NPC to PN-inducible apoptosis.

BACKGROUND AND AIM: To study the variation of the level of reactive oxygen species(ROS), oxidative DNA damage and antioxidative ability between Pten＋/＋MEFs and Pten－/－MEFs cells. MATERIALS AND METHODS: Fluorescence activated cell sorter(FACS), immunocytochemistry (ICC) and neutral single cell gel electrophoresis(SCGE) were employed to compare the differences of the levels of ROS , 8-hydroxy-2'-deoxyguanosine(8-OH-dG),double-strand breaks(DSBs)and antioxidative ability between Pten＋/＋MEFs and Pten－/－MEFs cells. RESULTS: In Pten－/－MEFs , the levels of ROS, 8-OH-dG and DSBs were increased. Moreover, its antioxidative ability was decreased. CONCLUSION: PTEN could regulate the level of ROS to affect oxidative DNA damage.

BACKGROUND AND AIM: To assess the role of genetic polymorphisms of metabolic enzyme Cytochrome P450 1A1(CYP1A1) in the risk of developing lung cancer for the people living in high radon-exposed area. MATERIALS AND METHODS: A case-control study was performed with 53 lung cancer patients and 72 frequency-matched controls. The associations between genotypes and risk of developing lung cancer were estimated by odds ratios (ORs) and their 95％ confidence intervals (CIs) calculated by unconditional logistic regression. RESULTS: Risk of developing lung cancer for heterozygous CYP1A1 (MSPⅠ) polymorphism was 1.03-fold (95％CI 0.468－2.28) higher than that for wild type of CYP1A1 (MSPⅠ) polymorphism. Stratified analysis showed that with effective dose<50 mSv the risk of developing lung cancer for heterozygous CYP1A1 (MSPⅠ) polymorphism increased to 4.29-fold (95％CI 0.582－88.2). In people heterozygous for CYP1A1 (MSPⅠ) polymorphism aged between 40 and 59, the risk of developing lung cancer was 1.22-fold higher than that for wild type of CYP1A1 (MSPⅠ) polymorphism. CONCLUSION: The present results indicated genetic polymorphisms of CYP1A1 might increase the risk of developing lung cancer, but the difference was not statistically significant.

BACKGROUND AND AIM: To study the effect of trichloroethylene(TCE) on the expression change of Rho GDIα gene at both mRNA and protein levels. MATERIALS AND METHODS: Western blot and real time quantitative RT-PCR were employed to detect the protein and mRNA levels of Rho GDIα in L-02 liver cells ,which were treated with DMSO and high concentrations of TCE. β-actin was selected as internal standard. RESULTS: The protein level of Rho GDIα was significantly up-regulated while its mRNA was significantly reduced. CONCLUSION: The Rho GDIα gene expression level showed specific changes after treatment with high concentration of TCE, providing important clues to the mechanism of TCE-induced damage in humans.

BACKGROUND AND AIM: To study the effect of grape procyanidins(GPC) on the expression of estrogen receptor in breast cancer cells. MATERIALS AND METHODS: The MCF_7 cells were cultured with different concentrations of GPC. The MCF_7 cells were divided into four groups: 200,100,10 μg/ml GPC groups and control group. The expressions of ER and Bcl_2 protein were assessed by immunohistochemistry. The proliferation activity of breast cancer cells was evaluated by MTT assay. RESULTS: The expression of ER protein in 100 and 200 μg/ml GPC groups were(85.02±1.53)％ and(73.14±1.05)％, respectively. The proliferative activity of the cells were 0.365±0.009 and 0.283±0.008, respectively. Compared with control group, all the results mentioned were significantly decreased (P<0.05). CONCLUSION: GPC could inhibit the expression of ER protein and proliferative activity of breast cancer cells.

BACKGROUND AND AIM: 1H nuclear magnetic resonance (1H NMR) spectroscopic methods were used to analyze serum obtained from rats treated with a range of doses of nano-copper particles in order to reveal the characteristics of the damage caused by nano-copper and identify the latent NMR biomarkers associated with the earlier damage. MATERIALS AND METHODS: 30 male Wistar rats were randomly assigned into five groups (6 rats per group), rats were given daily orogastric vehicle(1％ Hydroxypropylmethylcellulose), nano-copper (50, 100, 200 mg/kg) or micron-copper(200 mg/kg) for 5 days, and sacrificed on Day 6. The serum samples from all rats were collected and their 1H NMR spectra were acquired. PC analysis, blood biochemical analysis and histopathology examination for liver and kidney were performed simultaneously. RESULTS: For the rats dosed with 200 mg/kg nano-copper, increased levels in serum ALT, AST, TP, TG, TBA, TBILI, BUN and CREA, together with decreased ALP and TCHOL were marked compared with controls. Histopathology examination found hepatocellular dot necrosis, and widespread necrosis in the renal proximal tubules with protein cast in the tubule lumen, in which orange crystal deposition could also be found. For rats fed 50 and 100 mg/kg nano-copper, abnormalities included increased serum level of TCHOL and TG, as well as renal proximal tubular epithelial cellular swelling. The rats dosed with 200 mg/kg micron-copper particles showed slight damage. The metabonomic analysis of the serum samples revealed nano-copper disturbing cellular energy metabolism and serum lipid metabolism. These results were in agreement with the changes of serum biochemical and histopathology examinations. CONCLUSION: Liver and kidney were the potential target organs of nano-copper exposure. The damages of the target organs were associated with the disturbance of the cellular energy metabolism.

BACKGROUND AND AIM: To study teratogenicity of glycosides of chaenomeles speciossa (GCS) on ICR mice during the sensitive period. MATERIALS AND METHODS: The pregnant ICR mice were divided into five groups in this test, GSC groups (83.1,332.5, 1330.0 mg/kg) , one positive control group (CP) and one negative control group(0.5％CMC-Na). Every group consisted of 15 pregnant mice at least .The mice of the GCS groups and the negative group were treated with 0.02 ml/g orally during the period of organ formation(from Day 6 to Day 15,once a day),while the positive control mice received 0.01 ml/g intramuscular injection on Day 10. The pregnant mice were killed by cervical vertebral dislocation on Day 19, then the numbers of corpus lutea, living embryo, dead fetus and absorbed fetus were counted, the sex and appearance of the mice embryos were examined, tail length and weight were measured .After that half of living embryos of every pregnant mouse were used to study the bone development after ethanol fixing, potassium hydroxide melting, Alizarin Red staining and glycerin transparencing. The other living embryos were examined for the visceral development after Bouin's solution fixing. RESULTS:Compared with the negative control group, no abnormalities in the living embryos appearance, bones and viscera were found in any of the three dosages groups, while maternal body weight of highest dosage of GCS(1 330.0 mg/kg) increased slowly. CONCLUSION: GCS(83.1- 1 330.0 mg/kg) had no embryonic and teratogenic toxicity in this test.

BACKGROUND AND AIM:To study the hepatotoxicity and its probable mechanism(s) of a novel anti-HBV compound, Bay41-4109, using microarray technology. MATERIALS AND METHODS: Male Wistar rats were fed Bay41-4109 orally for 5 days. And Phenobarbital (PB), one of the typical inducers of CYP450, was used as a positive control in the study. The liver/body weight ratios and histological examination were conducted. In in vitro studies, the cytotoxicity of Bay41-4109 on HepG2 cells was detected using MTT chromometry. Then the effects of Bay41-4109 on liver gene expression profile in male Wistar rats and cultured HepG2 cells were both investigated with rat whole genome chip and human whole genome chip, respectively. Cluster analysis and the functions of differential expression genes were then analyzed. Some of the differential expression genes were authenticated by RT-PCR. RESULTS: The liver/body weight ratios were increased significantly, and focal necrosis was found in the liver in both Bay41-4109 and PB treated animals. The differential expression genes induced by Bay41-4109 were mainly related to drug metabolism, fat and energy metabolism, and 26 of them were similar to those induced by PB. In in vitro studies, the differential expression genes in HepG2 cells induced by Bay41-4109 at IC20 and IC50 concentrations were mainly relevant to fat, amino acids, energy metabolism, which coincided with the in vivo study. The differential expression genes could be authenticated by RT-PCR. CONCLUSION:The abnormal metabolism of fat and energy, and abnormal expression of CYP450 contributed to the hepatotoxicity of Bay41-4109.

BACKGROUND AND AIM: To investigate the free radical scavenging and antilipoperoxidant activities of Maydis stigma extract and their dose-response relationship. MATERIALS AND METHODS: Sprague-Dawley rats were killed and the livers were removed to isolate the microsome by differential centrifugation. The ethanol extract of Maydis stigma were obtained by recirculating. We investigated the effects of the ethanol extract of Maydis stigma (MSE) on luminol-enhanced chemiluminescence of superoxide/hydroxyl radical scavenging properties in cell free system. We also measured malondialdehyde (MDA) from the microsomal suspension and studied the relationship between the lipid peroxidation and the antioxidant metabolism of MSE in rat liver microsomes. RESULTS: MSE possessed very high radical scavenging activity in both chemiluminescence assays. Furthermore, the extract exhibited a significant concentration-dependent inhibition of lipid peroxidation in rat liver microsomes induced by Fe2＋/ascorbate, cumene hydroperoxide (CHP), and NADP＋/CCl4. CONCLUSION: The data clearly demonstrated the free radical scavenging and antilipoperoxidant properties of MSE supporting its reported biological activities.

BACKGROUND ＆ AIM: To study the effect of smoking in different areas with different environmental mutagens including natural radiation. MATERIALS AND METHODS: Peripheral blood was obtained from 10 smokers who had lived in Beijing for more than 40 years. Individual radiation dose was measured with a pocket dose meter. Chromosomes 1, 2, and 4 were painted for the analysis of translocations. The results were compared with those of 10 and 7 smokers in high background radiation area(HBRA) and its control area(CA), respectively;and 20, 15 and 16 non-smokers in Beijing, HBRA and CA, remote villages, in South China respectively. RESULTS: Frequencies of translocation were (10.6±3.1)‰, (11.1±3.6)‰ and (13.4±3.4)‰ in smokers and (9.6±5.0)‰, (11.7±4.7)‰ and (8.4±3.1)‰ in non-smokers in Beijing, HBRA and CA, respectively. There was a statistically significant difference (P<0.05, Mann-Whitney U test) in the frequencies of translocation between smokers and non-smokers in CA, but the difference between smokers and non-smokers was neither seen in HBRA or in Beijing. CONCLUSION: The effect of smoking seems to be suppressed by the environmental mutagens in Beijing as well as by the elevated level of natural radiation in HBRA.

BACKGROUND AND AIM: To explore the cigarette smoke condense(CSC) induced alteration of transcriptional profiling in papillomavirus_immortalized human bronchial epithelial cells(BEP2D). MATERIALS AND METHODS: We used CSC to treat BEP2D cells and examined the oncogenic transforming effects of CSC. Anchorage_ independent growth and the chromosome changes were used to investigate the various stages of transformation in BEP2D cells. Microarray assay was used to explore the CSC_induced alteration of transcriptional profiling. RESULTS: After CSC treatment, the P30 of BEP2D cells gained anchorage independence growth ability. The chromosomal number of the P40 cells was poly_ploid. In the earlier period of CSC treatment, 269 genes were down_regulated and 63 genes were up_regulated. In the advanced stage of CSC treatment, 316 genes were down_regulated and 147 genes were up_regulated. CONCLUSION: We successfully analyzed the alteration of transcriptional profile in BEP2D cells induced by CSC and identified a batch of genes related with the initiation and development of lung cancer.

BACKGROUND AND AIM: To investigate the expression of inducible nitric oxide synthase (iNOS) mRNA and its protein in Oral Squamous Cell Carcinoma (OSCC) and Precancerous Lesion(PL); in order to explore the impact of iNOS gene expression on the development of OSCC. MATERIALS AND METHODS: Immunohistochemistry technique (SABC) and in situ hybridization (ISH) assay were used to detect the expression of iNOS protein and iNOS mRNA in 10 specimens of normal oral mucosa,12 oral epithelial simple hyperplasia (SH),28 oral epithelial atypical hyperplasia (AH) and 32 OSCC. RESULTS: Both the expression of iNOS protein and mRNA were negative in the 10 normal oral mucosa.The positive rates in SH,AH and OSCC were 16.67％ 67.86％ and 78.13％ by SABC,16.67％、71.43％ and 75％ by ISH, respectively.No iNOS gene abnormality was found in OSCC by SABC and ISH.The positive rates of iNOS protein and iNOS mRNA were significant among these four groups of oral mucosa (P<0.01).Significant correlation between the expressions of iNOS protein and mRNA and the grade of atypical hyperplasia(AH) (P<0.05)was found. No significant difference of iNOS gene expression was found between AH and OSCC groups (P>0.05). CONCLUSION: The up_regulation of iNOS gene indicated that it may play important roles in the pathogenesis and development of OSCC. Determination of its gene products may provide evidence for early diagnosis.

BACKGROUND AND AIM: Effects of tanshinoneⅡA (TanⅡA) on proliferation and apoptosis of the human gastric cancer cell line BGC_823 were studied. MATERIALS AND METHODS: The inhibitory effect on proliferation of BGC_823 cells was evaluated in vitro by using MTT colorimetric assay after cells were treated with TanⅡA at various concentrations (0－10 μg/ml) for 48 h and 72 h. Cell apoptosis was analyzed by HE staining, DNA agarose gel electrophoresis and flow cytometry after BGC_823 cells were treated with 2, 5, 10 μg/ml TanⅡA for 72 h. RESULTS: TanⅡA inhibited the proliferation of BGC_823 cell markedly. The typical morphological features indicative of apoptotic state were seen under the light microscope. The DNA ladder was generated after treatment with TanⅡA at the concentrations of 5 and 10 μg/ml.The apoptotic rates were (20.60±1.84)％ and (31.03±1.47)％ in BGC_823 cells treated with 5, 10 μg/ml of TanⅡA, respectively. There was marked difference compared with the control group whose apoptotic rate was (5.23±0.39)％. CONCLUSION: TanⅡA could inhibit proliferation and induce apoptosis of human gastric cancer cell line BGC_823 in this test.

BACKGROUND AND AIM: To investigate the expressions of RhoC and CD44v6 proteins in gastric carcinoma (GC) and their relationship to clinicopathological factors. MATERIALS AND METHODS: Immunohistochemical staining SP method was used to evaluate the expressions of RhoC and CD44v6 in 97 cases of GC. RESULTS: 75(77.31％) and 81(83.50％)of 97 cases showed overexpressions for RhoC and CD44v6, respectively. There was a significant correlation between the overexpression of RhoC and CD44v6 (P<0.05). The expressions of RhoC and CD44v6 in GC were significantly associated with the depth of tumor invasion and TNM staging(P<0.05). Moreover, the RhoC overexpression was associated with lymph node metastasis(P<0.05). CONCLUSION: Overexpressions of RhoC and CD44v6 proteins are frequent events in GC. Measurement of these protein expressions might be used as a prognostic indicator for GC.

BACKGROUND AND AIM: To study the relation between the centromeric dots(Cd)variation in JEG_3 cells and PA_1 cells and the chromosome aneuploidy aberration。 MATERIALS AND METHODS: Chromosome of tumor cells were prepared with conventional method，chromosome of normal embryonic villi were treated directly. A Cd_NOR in_phase silver dye analysis technique modified by this laboratory was used to study centromeric dots(Cd) variation of JEG_3 cells and PA_1 cells. RESULTS: Frequency of Cd loss in JEG_3 cells was 1.43％, frequency of Cd duplication delay was 0.21％, frequency of small Cd was 1.52％ and that of Cd_NOR fusion was 1.16％。 Frequencies of Cd loss and Cd_NOR fusion in JEG_3 cells were significantly higher than those of normal embryonic villi(P<0.0125). Frequency of Cd duplication delay and small Cd showed no difference between JEG_3 cells and normal embryonic villi cells. Frequency of Cd loss in PA_1 cells was 1.22％, of Cd duplication delay was 0.95％, of small Cd was 1.81％,and that of Cd_NOR fusion was 1.03％。 Frequencies of Cd loss, Cd duplication delay and Cd_NOR fusion in PA_1 cells were significantly higher than those of normal embryonic villi cells(P<0.0125). Frequency of small Cd showed no difference between PA_1 cells and normal embryonic villi. CONCLUSION: Cd loss and Cd_NOR fusion might be related with aneuploidy aberration of JEG_3 cells.Cd loss,Cd duplication delay and Cd_NOR fusion might be related with aneuploidy aberration of PA_1 cells.

BACKGROUND AND AIM: Artemisinin_piperaquine combination (ATQ) is comprised of artemisinin and piperaquine for the treatment of falciparum malaria. To test the developmental toxicity of the combination, embryo_fetal development studies were conducted in rats. MATERIALS AND METHODS: SD rats were divided into 6 groups (18 animals per group). On days 7－17 of gestation, ATQ in 4 doses of 35, 70, 120 and 200 mg/(kg·d) were orally administrated to 4 groups of rats, and a similar group was dosed with the vehicle and cyclophosphamide to serve as control. Body weight, food consumption and clinical observation data were collected during the study. On day 20 of gestation, all rats were sacrificed. RESULTS: Fetal developmental retardation was observed in groups of 70, 120 and 200 mg/(kg·d)doses. Groups of 120 and 200 mg/kg doses showed embryotoxicity, with fetal resorption of 23.5％ and 36.4％, respectively, and a low incidence of skeletal abnormalities with protruding, absent, incomplete ossification and short supernumerary ribs. No toxicity was observed in group of 35 mg/kg dose. CONCLUSION: ATQ had developmental toxicity and 35 mg/(kg·d)was the maximum safe dose in pregnant SD rats.