In order to establish an ideal research platform to make further study of the relationship between the two genes , hOGG1 and hMTH1, two cell models with gene defect were established. METHODS: The lentivirus vector with shRNA targeting human 8-oxoguanine DNA glycosylase 1(hOGG1) mRNA and 8-oxoguanine nucleoside triphosphatase 1(hMTH1) mRNA were transfected into 293FT cells by liposome. Then the lentivirus supernatant was obtained and used for infecting human embryonic lung fibroblasts(HFL). The defective cells were selected with blasticidin, and fluorescence microscope was used as a tool for observing the packaging efficiency and infection efficiency. The efficacy of gene knockout was tested by Real-time RT PCR. RESULTS: The lentivirus with high titer were obtained and the hOGG1- deficient and the hMTH1- deficient HFL cell strains were obtained after blasticidin selection. The level of hOGG1 and hMTH1 mRNA expression were decreased, 90% and 60%, respectively. CONCLUSION: Lentivirus packaging technology could be mastered skillfully. hOGG1-deficient and hMTH1-deficient HFL cell models were successfully established.

To investigate the association of single nucleotide polymorphisms of (manganese superoxide dismutase, MnSOD) gene with radiosensitivity of esophageal squamous cell carcinoma. METHODS： The MnSOD Ala16Val was genotyped by polymerase-chain reaction-restriction fragment length polymorphism(PCR-RFLP) analysis in 93 esophageal squamous cell carcinoma patients. All patients received 3D-CRT or the conventional radiotherapy. RESULTS: The frequencies of T/T and C/T+C/C allelotype among three grades of curative effect were 59.1%, 40.9%; 77.8%, 22.2%; 62.5%, 37.5% respectively. There was no statistical difference in allelotype distribution between three grades. When the length of esophagus cancer was 5 cm or less than there was no statistical difference in allelotype distribution between three grades of curative effect. But when the length was more than 5 cm a significant difference was observed in the MnSOD allelotype distribution among different length (χ2=2.658, P＜0.05). The curative effect of radiotherapy in patients with C/T+C/C allelotype was better than patients with allelotype T/T when the length was more than 5 cm. There was no difference of MST and 1-year survival rates in patients with MnSOD-9 T/T genotype and MnSOD-9 T/C＋C/C genotype(17 months, 68%, 35.82% vs 22 months, 73%,34.62% P > 0.05). CONCLUSION： The MnSOD Ala16Val appears to be associated with an improved radiosensitivity in patients when the length of esophagus lesion was more than 5 cm.

o study the antioxidation of vitamin E and/or β-carotene on mice induced by radiation. METHODS： Mice were divided randomly into 5 groups of normal control, positive, vitamin E, β-carotene, vitamin E plusβ-carotene. All of the animals except the normal control were irradiated with 4.5 Gy of 60Coγ. After the radiation, the vitamin supplementation animals were given vitamin E [30 mg/(kg·d)] and/or β-carotene [20 mg/(kg·d)]. Three days later, the animals were sacrificed. The retinol binding protein (RBP) in serum was analyzed with enzyme-linked immunosorbent assay (ELISA), and the levels of malondialdehyde (MDA) and reduced glutathione (GSH) in serum and liver were determined with fluorometry. RESULTS: 60Coγradiation decreased the level of RBP in serum. Supplementation of vitamin E and/or β-carotene showed certain protection. Vitamin E and/or β-carotene also inhibited the increase of MDA and the decrease of GSH in serum and liver induced by 60Coγ radiation. Vitamin E alone showed the best protection. CONCLUSION： Both vitamin E and β-carotene showed protective effects on the oxidative injuries in mice induced by radiation. But the combined use of vitamin E andβ-carotene showed antagonistic rather than synergistic effect.

To investigate the possible association of the transforming growth factor-beta receptor type 1 gene(TGFBR1)*6A and Int7G24A polymorphisms with susceptibility to esophageal squamous cell carcinoma(ESCC) in a population of north China. METHODS: Polymerase chain reaction(PCR) and polymerase-chain reaction-restriction fragment length polymorphism(PCR-RFLP) analyses were used to detect the genotype of *6A(exon 1) and Int7G24A(intron 7) polymorphisms in ESCC. The expression of TGFBR1 protein in tumors and corresponding normal tissues was detected by immunohistochemistry method. RESULTS: The genotype and allelotype distributions of TGFBR1 *6A polymorphism in ESCC patients were not significantly different from those in healthy controls(P＞0.05). The overall genotype and allelotype distributions of TGFBR1 Int7G24A polymorphism in ESCC patients were significantly different from those in healthy controls(P＜0.05). The A allelotype significantly elevated the risk of developing ESCC [ adjusted odds ratio(OR) =1.38, 95% confidence interval(CI) =1.04 - 1.75]. Compared with GG genotype, the AA genotype significantly increased the risk of developing ESCC(adjusted OR=2.23, 95%CI=1.19-3.81). Compared with GG genotype, GA and AA carriers of stage Ⅲ and Ⅳ had heightened risk(adjusted OR=1.61，95%CI=1.10 - 2.21). The protein expression of TGFBR1 in ESCC tumor tissues(32.1%) was significantly lower than that in corresponding normal tissues(97.7%)( P＜0.01 ). However, the protein expression did not correlate with genotypes of Int7G24A and *6A. CONCLUSION: A allelotype of TGFBR1 Int7G24A may be one of the factors that affects the risk of developing ESCC in northern China.

To explore the effects of arsenic trioxide on radiosensitivity and the possible mechanism in lung cancer xenografts. METHODS: The tumor-bearing C57BL/6 mouse model was established by injecting Lewis lung cancer cells into right infra-axillary dermis. 40 mice were randomized into 4 groups: control group(peritoneal injection 0.9％NS,0.2 ml); As2O3 group(peritoneal injection,2.0 mg/kg,0.2 ml As2O3); irradiation group(peritoneal injection 0.9％NS,0.2 ml＋6MeV Electron Beam,10 Gy); As2O3＋irradiation group(peritoneal injection, 2.0 mg/kg, 0.2 ml As2O3＋6MeV Electron Beam,10 Gy). After experiments, mice were sacrificed, then the tumors were separated and weighed. Response to irradiation was evaluated by tumor- inhibiting rate. The expressions of VEGF and Ku70 mRNA were evaluated by RT-PCR. The protein levels of VEGF and Ku70 were measured by immunohistochemical staining. RESULTS: The Lewis lung cancer-bearing model was successfully established in mice. As2O3＋irradiation could significantly increase the tumor-inhibiting rate and downregulate the expression of VEGF and Ku70 of irradiated carcinoma xenografts, (Compared with As2O3 group or irradiation group, P＜0.05). CONCLUSION: Arsenic trioxide could sensitize lung cancer xenografts to ionizing irradiation. This effect was probably mediated by downregulating the expressions of VEGF and Ku70.

To identify the differentially expressed miRNAs in malignantly transformed L02 cells(L02T) induced by aflatoxin B1(AFB1), we performed miRNA microarray on both control cells(L02) and L02T cells. METHODS: L02T cells were obtained after exposure to aflatoxin B1(AFB1) several times. The comparison of differential expression profiles between L02 and L02T cells was performed and analyzed. The differentially expressed miRNAs were then selected for validation by semi-quantitative real-time PCR. The targets of miRNAs were predicted by TargetScan program. RESULTS: 856 human miRNAs were analyzed by miRNA microarray. 25 differentially expressed miRNAs were found in L02T cells compared with L02 cells, with 15 upregulated and 10 downregulated. Among these miRNAs, miR-320a, miR-638 and miR-98 were validated by quantitative real-time PCR. Moreover, predicted by TargetScan program, we identified 4 genes that were potentially targeted by miR-638. These genes might be associated with hepatic cell transformation induced by AFB1. CONCLUSION: 25 differentially expressed miRNAs were identified in AFB1-transformed L02T cells. These miRNAs may play important roles in the process of malignant transformation of human cells.

To examine the value of micronucleus high throughput screening method in micronucleus assay and develop an effective, economical, simple and fast micronucleus high throughput screening method. METHODS: To evaluate micronucleus rate with CHO cells using AssayScan High Throughput Screening system. RESULTS: B[α]P could induce micronucleus formation significantly at 25.15 μg/ml and 50.3 μg/ml. Etoposide significantly induced micronucleus formation between 0.16 μg/ml and 20 μg/ml concentrations; between 1.25 μg/ml and 20 μg/ml, cell viability was less than 50%. 2-anthramine could significantly induce micronucleus formation at 6.44 μg/ml, 12.88 μg/ml, 25.75 μg/ml and 51.5 μg/ml. Colchicine significantly induced micronucleus formation between 0.08 μg/ml and 20.4 μg/ml. EMS significantly induced micronucleus formation at 0.754 mg/ml, 1.509 mg/ml and 3.018 mg/ml. Chromium Chloride significantly induced micronucleus formation at 2.344 μg/ml. Whilst MMS could significantly induce micronucleus formation at 0.101 mg/ml. CONCLUSION: Micronucleus high throughput screening method could satisfy the requirement for an effective, economical, reliable and fast screening method.

To explore the inhibitory effects of catechin on vascular smooth muscle cells (VSMCs)and its possible mechanisms. METHODS: After VSMCs were exposed to different doses of catechin at 50, 100, 150, 200, 250, 300 μg/ml, for 24 h and 48 h cell morphology was observed. MTT assay was used to test cell viability, mRNA expressions of MMP-2 and TIMP-1 were detected by RT-PCR analysis. RESULTS: Cell growth was inhibited after exposure to 250 μg/ml, and mRNA expression MMP-2 was down-regulated. Meanwhile mRNA expression of TIMP-1 was up-regulated. CONCLUSION: Catechin could inhibit VSMCs and regulate mRNA expressions of MMP-2 and TIMP-1.

To investigate the expression and biological significance of Ras protein activator like-1 gene (RASAL1) in normal human gastric epithelial cell line and different differentiated gastric cancer cell lines. METHODS: The expressions of RASAL1 mRNA and protein were respectively detected by PT-PCR and Western blot in three kinds of gastric cancer cell lines, including well differentiated MKN-28, moderately differentiated SGC-7901, poorly differentiated BGC-823, and normal gastric epithelial cell line GES-l. The mutation of K-Ras gene codon 12 was detected by PCR and gene sequencing. RESULTS: The results of PT-PCR and Western blot showed that both of the expressions of RASAL1 mRNA and proteins were decreased in all three gastric cancer cell lines as compared with the normal gastric epithelial cell line GES-l. It’s expression level was correlated with the differentiation: the poorest differentiation the lowest expression. The mutation of K-Ras gene codon 12 was not found in any of the gastric cancer cell lines. CONCLUSION: RASAL1 expression was reduced in the gastric cancer cell line that contain wild type K-Ras gene, and its expression level may be correlated with the degree of differentiation.

To evaluate clusterin protein level in the peripheral blood samples from epithelial ovarian cancer patients, and to explore its clinical significance. METHODS: Peripheral blood samples were obtained from 137 patients with epithelial ovarian cancer, 12 with borderline ovarian tumor, 10 with benign ovarian tumor, 41 with benign pelvic lesion and 58 healthy women. The plasma clusterin level was measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: The mean level of plasma clusterin in epithelial ovarian cancer patients was significantly higher than that in healthy women (P=0.021). The mean plasma clusterin in epithelial ovarian carcinoma patients with metastasis was significantly higher than those without (P＜0.01). The level of plasma clusterin did not correlate with the stage, grade and lymph node metastasis. CONCLUSION: Plasma clusterin level was increased in the peripheral blood of ovarian cancer patients. In epithelial ovarian carcinoma，the level of plasma clusterin did correlate with distant metastasis.

o investigate the protective effects of genistein on apoptosis of rat cerebellar granule neurons induced by acrylamide. METHODS: Rat cerebellar granule neurons were prepared from the cerebellar cortex cells of 5-7day-old SD rats pups. The neurons were identified by Nissl staining method.The 8-day cultured cells passage were divided randomly into control group, acrylamide model group, genistein pretreatment groupⅠ,Ⅱ,Ⅲ(cerebellar granule neurons were pretreated with 10,25,50 μmol/L genistein for 12 hours,the culture medium discarded and fresh DMEM/F12 solution added with the above mentioned concentration of genistein with 10 mmol/L acrylamide to cultured neurons for 24 hours). The neuronal viability was measured by MTT. Morphology of neurons and their nuclei were examined by phase-contrast and Hochest33342 staining,respectively. The ratio of apoptotic cells was detected by TUNEL. RESULTS: The cell survival rates of genistein pretreatment group Ⅱ and Ⅲ were not significantly higher than acrylamide model group. Genistein pretreatment groupⅠsignificantly prolonged the cell survival rate. The effects of diminished neuronal body, chromatin concentration and the ratio of apoptotic cells induced by acrylamide were markedly weakened. CONCLUSION: Genistein did not show a dose-dependent effect on protection. The appropriate concentration of 10 μmol/L was found to protect against apoptosis induced by acrylamide in primary culture of cerebellar granule neurons.

To investigate the effects of Ashitaba chalcone (AC) on Caspase-3 and Bax protein expressions in mouse hepatocarcinoma cells. METHODS: Fifty mice inoculated with hepatocarcinoma 22 cells were divided into five groups, 10 mice per group. 5,20,40 mg/kg AC were given daily by mouth to form low, medium and high dose groups, respectively. Normal saline by mouth was given to the tumor control group. 20 mg/kg cytoxan(CTX) by injection every other day were given to the CTX group.10 days later, all mice were sacrificed. The levels of the Caspase-3 and Bax protein expressions were measured by immunohistochemistry, and the proliferation activity of hepatocarcinoma cells was determined by MTT assay. RESULTS: The expressions level of Caspase-3 and Bax protein in tumor control group were 5.00% and 4.68%, respectively, and those of the high-dose group were 38.52% and 35.76%. The differences between two groups were significant (P<0.05). The cell proliferation activity of tumor control group and high-dose group were 1.135±0.032 and 0.716±0.018, respectively. The difference was significant (P<0.05). The rumor weight in AC 20, 40 mg/kg were significantly lower than that in tumor control group (P<0.05). CONCLUSION: AC could induce the expressions of Caspase-3 and Bax protein.

To analyze the expressions of P63, Calponin and D2-40 in myoepithelial cells of salivary gland tumors and to investigate the value of D2-40 in identification of myoepithelial cells in salivary gland tumor. METHODS: Various types of salivary gland tumor specimens were collected during surgeries in affiliated Yijishan Hospital from January 2004 to January 2010. We used immunohistochemical technique (S-P) to examine the expressions of P63, Calponin and D2-40 in each salivary gland tumor organization. RESULTS: P63, Calponin, D2-40 were expressed in myoepithelial cells, and the expressions of P63, Calponin, D2-40 were 82.14%, 76.79% and 66.07%, respectively. D2-40 was expressed in polymorphic adenomas, adenoid cystic carcinoma, epithelial-myoepithelial carcinoma and the expressions were 94.12%, 61.90% and 66.67%, respectively. D2-40 was not expressed in malignant polymorphic adenomas. The expression of D2-40 in polymorphic adenomas, tissues adjacent to the salivary gland malignancy and the cancerous tissues showed decreasing expressions that were significant (P＜0.05). CONCLUSION: D2-40 could be one kind of ideal salivary gland tumor myoepithelial cell marker. Low expression of D2-40 is probably an indicator of malignant progresion of salivary gland tumor.

To evaluate the correlation of complications with opened or closed posterior peritonum in radical hysterectomy for cervical cancer. METHODS: From January 2006 to December 2008，260 patients with radical hysterectomy and lymphadenectomy for cervical cancer from the Cancer Hospital affiliated to Shantou University Medical College were divided into two groups: 115 cases with peritoneum opened in group A and 145 cases with peritoneum closed in group B. The operation time, lymphatic cyst formation, obstruction of lymphatic return, phlebothrombosis, intestinal obstruction were compared between the two groups. RESULTS: The operation time of group A was obviously shorter than group B (P < 0.05). Lymphatic cyst formation in group A was significant(P < 0.05) compared to group B. Group A had fewer (P< 0.05) obstruction of lymphatic return or phlebothrombosis than the group B. Intestinal obstruction was insignificantly different (P > 0.05) between the two groups. CONCLUSION: Patients treated with peritoneum opened in radical hysterectomy and lymphadenectomy for cervical cancer could shorten the operation time, and would result in fewer postoperative complications.

The study focused on the effects of the water extract of Pu' er tea on genetic damage induced by mitomycin C (MMC) in human lymphocyte cell line. METHODS: The lymphoblast cell line GM12593 was cultured in RPMI-1640 medium plus MMC (0.1 μg/ml) and different combinations of red and raw Pu'er tea (0~1 mg/ml) for 24 h. Cytochalasin B was added and cells were cultured for another 28 h, centrifuged and put on slides. The frequencies of micronucleated binucleated cells were analysed. RESULTS: Fermented (red) Pu'er tea (0.125 mg/ml, 0.25 mg/ml) and raw (green) Pu'er tea (0.125 mg/ml) significantly reduced the frequency of micronucleated binucleated cells induced by MMC (P<0.05). The effect of fermented Pu'er tea in preventing genetic materials induced by MMC was slightly stronger. CONCLUSION: Pu'er tea was able to reduce the genetic damage induced by MMC.

To evaluate in vitro genotoxicity of emodin and rhein. METHODS: The WTK1 cells were treated by emodin and rhein of different concentrations (20, 40, 80, 120 μg/ml) and then the comet assay, in vitro micronucleus test and TK gene mutation assay were conducted simultaneously. The solvent control and positive control (mthylmethane sulfonate，MMS) groups were included in the study. RESULTS: Positive results were found at the concentrations of 120 μg/ml and 80 μg/ml of emodin in comet assay and tk gene mutation analysis. High dose of rhein (120 μg/ml) also showed weak mutagenicity in TK gene mutation analysis. CONCLUSION: Under the present experimental conditions, emodin and rhein showed weak mutagenicity.

To understand the level of bioligical contamination by toxins including aflatoxinB1(AFB1), FumonisinB1(FB1), DON and T-2 toxins of Pu'er tea in a tea market of Guangzhou,China, to provide useful information and data for safety and related health standards. METHODS: Sample 70 Pu'er tea randomizely in a Guangzhou tea market. All the samples were assayed with ELISA kit for FB1, DON, T-2 toxin, and with immunoaffinity chromatography - high performance liquid chromatography for AFB1. RESULTS: The AFB1 level of 8 among 70 samples was above the limit of national standard(5 μg/kg), and the DON level of 63 samples above the national standard(1 mg/kg), while the levels of FB1 and T-2 toxin were within the standards(1 mg/kg and 100 μg/kg，respectively). CONCLUSION: AFB1 and DON in our samples were higher and exceeded the allowed standards to some degree. Althouth the levels of FB1 and T-2 were within eimits below, their existence in Pu'er tea should require close attention .