Study on DNA methylation in HEB cells exposed to PM(2.5) by application of methylation chip technology / 中华劳动卫生职业病杂志

Objective: To screen the differential methylation sites, genes and pathways of air pollution fine particles (PM(2.5)) on human bronchial epithelial (HBE) cells by methylation chip and bioinformation technology, so as to provide scientific basis for further study of the toxicological mechanism of PM(2.5) on HBE cells. Methods: In August 2020, HBE cells were infected with 10 μg/ml and 50 μg/ml PM(2.5) aqueous solution for 24 h, namely PM(2.5) 10 μg/ml exposure group (low dose group) and PM(2.5) 50 μg/ml exposure group (high dose group) ; uninfected HBE cells were used as control group. The DNA fragments were hybridized with the chip, the chip scanned and read the data, analyzed the data, screened the differential methylation sites, carried out GO analysis and KEGG analysis of the differential methylation sites, and analyzed the interaction relationship of the overall differential methylation sites by functional epigenetic modules (FEMs). Results: Compared with the control group, 127 differential methylation sites were screened in the low-dose group, including 89 genes, including 55 sites with increased methylation level and 72 sites with decreased methylation level. The differential methylation sites were mainly concentrated in the Body region and UTR region. Compared with the control group, 238 differential methylation sites were screened in the high-dose group, including 168 genes, of which 127 sites had increased methylation level and 111 sites had decreased methylation level. The differential heterotopic sites were mainly concentrated in the Body region and UTR region. Through FEMs analysis, 8 genes with the most interaction were screened, of which 6 genes had significant changes in methylation level. MALT1 gene related to apoptosis was found in the heterotopic site of methylation difference in low-dose group; PIK3CA and ARID1A genes related to carcinogenesis were found in the heterotopic sites of methylation difference in high-dose group; TNF genes related to tumor inhibition were found in the results of FEMs analysis. Conclusion: After PM(2.5) exposure to HBE cells, the DNA methylation level is significantly changed, and genes related to apoptosis and carcinogenesis are screened out, suggesting that the carcinogenic mutagenic effect of PM(2.5) may be related to DNA methylation.

Characteristics of Atmospheric Fine Particulate Matter (PM ) Induced Differentially Expressed Proteins Determined by Proteomics and Bioinformatics Analyses / 生物医学与环境科学（英文）

Objective@#To screen the differentially expressed proteins (DEPs) in human bronchial epithelial cells (HBE) treated with atmospheric fine particulate matter (PM ).@*Methods@#HBE cells were treated with PM samples from Shenzhen and Taiyuan for 24 h. To detect overall protein expression, the Q Exactive mass spectrometer was used. Gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), and Perseus software were used to screen DEPs.@*Results@#Overall, 67 DEPs were screened in the Shenzhen sample-treated group, of which 46 were upregulated and 21 were downregulated. In total, 252 DEPs were screened in the Taiyuan sample-treated group, of which 134 were upregulated and 118 were downregulated. KEGG analysis demonstrated that DEPs were mainly enriched in ubiquitin-mediated proteolysis and HIF-1 signal pathways in Shenzhen PM samples-treated group. The GO analysis demonstrated that Shenzhen sample-induced DEPs were mainly involved in the biological process for absorption of various metal ions and cell components. The Taiyuan PM -induced DEPs were mainly involved in biological processes of protein aggregation regulation and molecular function of oxidase activity. Additionally, three important DEPs, including ANXA2, DIABLO, and AIMP1, were screened.@*Conclusion@#Our findings provide a valuable basis for further evaluation of PM -associated carcinogenesis.

Metal elements analysis and risk assessment of carcinogenicity on PM2.5 samples collected from Shenzhen and Taiyuan / 中华疾病控制杂志

Objective To conduct metal elements analysis and risk assessment of carcinogenicity on Particulate Matter 2.5 ( PM2.5) collected from Shenzhen and Taiyuan. Methods PM2.5 samples were collected in Shenzhen and Taiyuan from 2017 to 2018. Ten heavy metal elements in PM2.5 samples were detected by inductively coupled plasma mass spectrometry (ICP-MS). Health risk assessment was conducted using the recommended United States Environmental Protection Agency (EPA) model. Results Metal elements found in PM2.5 samples from Shenzhen included (in decreasing order of concentration) Al, Pb, Mn, Cr, Cu, V, As, Ni, Cd and Co. Their levels were 1 807.67, 31.02, 30.63, 17.37, 17.32, 11.59, 6.98, 4.76, 2.24, 2.20 ng/m3, respectively. Metal elements in PM2.5 samples from Taiyuan included Al, Mn, Pb, Cr, Cu, As, Ni, V, Cd and Co. Their levels were 2 817.64, 91.04, 63.33, 26.56, 24.69, 11.82, 10.39, 4.46, 3.42, 1.01 ng/m3, respectively. There were significant differences among Pb, Mn, As, Ni levels between Shenzhen and Taiyuan (all P1.00×10-4), then followed by As, Ni and Cd (1.00×10-6-1.00×10-4). Pb had the lowest risk (<1.00×10-6). Conclusion Some of the metal elements in PM2.5 samples collected from Shenzhen and Taiyuan have carcinogenicity risk. Further researches and measures for prevention and control should be considered.

Expression of c-MET, EGFR and HER-2 of human gastric adenocarcinoma / 临床与实验病理学杂志

Purpose To investigate the expression status and their clinical significances of c-MET, epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor-2 (HER-2) in gastric adenocarcinoma (GC). Methods Tissue samples from 442 cases of GC in patients who accepted D2/D3 radical gastrectomy with R0 resection were stained by immunohistochemistry against c-MET, EGFR and HER-2.Results Over expression of c-MET, EGFR and HER-2 was identified in 195/442 (44.1％), 47/442 (10.6％) and 152/442 (34.4％) GC patients, respectively. Over expression of cMET was more often identified in GC patients with deeper T (P= 0.016), nerve involvement (P = 0.006) and the Lauren diffuse type (P = 0.029). EGFR in cases with vessel permeation (P = 0.012), and HER-2 in cases of distant metastasis (P =0.031), non-nerve involvement (P = 0.024), the Lauren intestinal type (P < 0.001) and G1/G2 grade (P < 0.001). Conclusion The receptors tyrosine kinase (RTKs) markers of cMET, EGFR and HER-2 might involve in the advance of GC, such as invasion and metastasis. The expression status of them could be used as the risk prediction and even the basis for future personalized therapy, especially for tyrosine kinase inhibitor (TKI) therapy, for GC patients.

Interference of DEHP on the key genes of glucose and lipid metabolism in HepG2 cells / 中国职业医学

OBJECTIVE: To investigate the effects of di-( 2-ethylhexyl) phthalate( DEHP) on the expression of the key genes involved in glucose and lipid metabolism,and explore the toxicity of DEHP on the glucose and lipid metabolism in HepG2 cells cultured in vitro. METHODS: HepG2 cells in logarithmic growth phase were divided into DEHP exposure group and control group. The exposure group was exposed to DEHP with different final concentrations( 5,10,50,100,500 and1 000 μmol / L),and the control group was exposed to dimethyl sulfoxide of corresponding concentrations. After 24 hours of DEHP exposure,real-time fluorescence quantitative polymerase chain reaction( Q-PCR) was applied to detect the level of mRNA transcription of peroxisome proliferators-activated receptor α( PPARα), which is an endogenous marker indicating the success of DEHP exposure. In addition,the level of mRNA transcription of key genes involved in glucose and lipid metabolism were also measured by Q-PCR,including glucose-6-phosphatase( G-6-Pase),phosphoenolpyruvate carboxykinase( PEPCK),stearoyl-coenzyme A desaturase 1( SCD1),fatty acid synthase,sterol regulatory elementbinding protein 1c and acetyl Co A carboxylase 1. P ≤0. 008 was considered as statistical significance. RESULTS: After DEHP exposure,the mRNA transcription level of PPARα was significantly elevated in all exposure groups( P < 0. 008)except for 5 μmol / L DEHP exposure group,which indicated the successful establishment of DEHP exposure model. The mRNA transcription level of G-6-Pase was significantly increased in 100 and 500 μmol / L DEHP exposure groups( P ≤0. 008) when compared with the controls; the PEPCK mRNA transcription level of showed no significant differences between the 6 DEHP exposure groups and their corresponding control groups( P > 0. 008). The mRNA transcription level of SCD1 was significantly down-regulated in 100 μmol / L DEHP exposure group( P < 0. 008) when compared with its control. The mRNA transcription level of other key genes involved in the lipid metabolism were not significantly altered after DEHP exposure( P > 0. 008). CONCLUSION: The effect of DEHP on glucose metabolism was mainly manifested by promoting G-6-Pase gene expression,which is the rate-limiting enzyme for gluconeogenesis. The effect of DEHP on the lipid metabolism of HepG2 cells was limited.

Effects of trichloroethylene on hepatotoxicity in cytochrome 2E1-silenced hepatocytes / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To prepare cytochrome (CYP)2E1-silenced hepatocytes by lentivirus-mediated RNA interference technology and to investigate the hepatotoxicity of trichloroethylene (TCE) in CYP2E1-silenced hepatocytes.</p><p><b>METHODS</b>Short hairpin RNA fragments were designed and synthesized and were then ligated into the lentiviral vector; single colonies were screened; the plasmid was extracted after PCR and sequence identification and then transferred into L02 hepatocytes; the CYP2E1-silenced hepatocytes were selected; real-time quantitative PCR and Western blot were used to evaluate the interference effects. The obtained CYP2E1-silenced hepatocytes, as well as normal L02 hepatocytes, were treated with TCE (0, 0.25, 0.50, 1.00, 2.00, and 4.00 mmol/L). The cell viability and half maximal inhibitory concentration (IC50) of TCE were measured; the apoptotic rate of cells was measured by flow cytometry; the mRNA expression levels of apoptosis genes and oncogenes were measured by real-time quantitative PCR.</p><p><b>RESULTS</b>The IC50s of TCE for L02 hepatocytes and CYP2E1-silenced hepatocytes were 15.1 mmol/L and 23.6 mmol/L, respectively. The apoptotic rate increased as the dose of TCE rose in the two types of cells; the CYP2E1-silenced hepatocytes hada significantly lower apoptotic rate than L02 hepatocytes when they were exposed to 2.0 and 4.0 mmol/L TCE (P < 0.05 or P < 0.01). The mRNA expression level of bcl-2 (anti-apoptosis gene) in CYP2E1-silenced hepatocytes was 15% ∼ 60% higher than that in L02 hepatocytes (P < 0.01), while the mRNA expression levels of caspase-3 and caspase-9 (apoptosis genes) in CYP2E1-silenced hepatocytes were 30% ∼ 60% lower than those in L02 hepatocytes (P < 0.01). The mRNA expression level of p53 (cancer suppressor gene) in CYP2E1-silenced hepatocytes was 81 - 278% higher than that in L02 hepatocytes (P < 0.01), while the mRNA expression levels of c-fos and k-ras (oncogenes) in CYP2E1-silenced hepatocytes were 20-68% lower than those in L02 hepatocytes (P < 0.01).</p><p><b>CONCLUSION</b>CYP2E1-silenced cells can be successfully prepared by lentivirus-mediated RNA interference technology. Silencing CYP2E1 gene can reduce the hepatotoxicity of TCE and inhibit the expression of some apoptosis genes and oncogenes, suggesting that CYP2E1 gene plays an important role in TCE metabolism and is related to the hepatotoxicity of TCE.</p>

Study on sperm damage caused by trichloroethylene in male rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study in vitro sperm damage caused by trichloroethylene in male rats.</p><p><b>METHODS</b>Sperms of Sprague-Dawley (SD) rats were collected 4 hours after being contaminated by trichloroethylene of 0, 2, 4, 6, 8, and 10 mmol/L in vitro. Giemsa staining was performed to observe the morphological changes of sperms, and flow cytometer was used to detect the changes in mitochondrial membrane potential.</p><p><b>RESULTS</b>The sperm motilities in 6, 8, and 10 mmol/L trichloroethylene groups decreased significantly compared with that in control group (P <0.01); the sperm aberration rates in 8 and 10 mmol/L trichloroethylene groups were significantly higher than that in control group (P<0.01). With the increase in exposure dose, the proportion of sperms with reduced mitochondrial membrane potential increased, and there were significant differences in sperm apoptosis rate between the 4, 6, 8, and 10 mmol/L trichloroethylene groups and control group (P<0.01).</p><p><b>CONCLUSION</b>In vitro exposure to trichloroethylene can reduce sperm motility and increase the aberration rate and apoptosis rate of sperms in male SD rats.</p>

Study on mRNA expression of immune-related genes in patients with allergic dermatitis induced by trichloroethylene / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study mRNA expression of immune-related genes (Foxp3, GATA3, CTLA4 and T-bet) in peripheral blood of the patients with allergic dermatitis induced by trichloroethylene (TCE).</p><p><b>METHODS</b>The peripheral blood samples were collected from 8 healthy workers (control group) and 8 patients with allergic dermatitis induced by TCE (case group). Real-time quantitative PCR was applied to detect mRNA expression of immune-related genes (Foxp3, GATA3, CTLA4, T-bet).</p><p><b>RESULTS</b>The mRNA expression levels of Foxp3, GATA3 and CTLA4 genes increased by 115%, 97% and 241% in case group, as compared with control group (P < 0.01). The mRNA expression level of T-bet gene decreased by 47% in case group, as compared with control group (P < 0.01).</p><p><b>CONCLUSION</b>The mRNA expression levels of some immune-related genes changed in patients with allergic dermatitis induced by TCE, those genes may play an important role in TCE-induced allergy.</p>

A cell-based detection of ciguatoxin using sodium fluorescence probe / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a cell-based detection method of ciguatoxin using fluorescence assay.</p><p><b>METHODS</b>Mouse neuroblastoma N-2A cells were exposed to ouabain and veratridine and different concentrations of standard ciguatoxin samples (P-CTX-1) to establish the curvilinear relationship between the toxin dosage and fluorescence intensity using the sodium fluorescence probe CoroNaTM Green. The toxicity curvilinear relationship was also generated between the toxin dosage and cell survival using CCK-8 method. Based on these standard curves, the presence of ciguatoxin was detected in 33 samples of deep-sea coral fish.</p><p><b>RESULTS</b>A correlation was found between the detection results of cell-based fluorescence assay and cytotoxicity assay, whose detection limit reached 103 g/ml and 1012 g/ml, respectively. The cell-based fluorescent assay sensitivity showed a higher sensitivity than cytotoxicity assay with a 2-4 h reduction of the detection time.</p><p><b>CONCLUSIONS</b>The cell-based fluorescent assay can quickly and sensitively detect ciguatoxin and may serve as a good option for preliminary screening of the toxin.</p>

Screening and identification of differential serum proteins related to dermatitis medicamentosa-like of trichloroethylene / 中华预防医学杂志

<p><b>OBJECTIVE</b>To screen and identify differential serum proteins which might be involved in dermatitis medicamentosa-like of trichloroethylene (DMLT).</p><p><b>METHODS</b>Three groups of sera were collected from population exposed to trichloroethylene (TCE) (group I), patients suffering from DMLT (group II), and the healed cases (group III). After removing albumin and IgG in the three pools of sera, a comparative proteomic analysis was carried out. The images were analyzed using ImageMaster Platinum 2D 5.0 to screen the differentially expressed proteins. The protein spots were then subjected to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and tandem mass spectrometry sequencing of tryptic peptides for further identification.</p><p><b>RESULTS</b>The depletion of albumin and IgG greatly increased the number of protein spots to 300 ± 12.Five differential spots were identified, which were complement component C4b, apolipoprotein A-I, apolipoprotein C-III apolipoprotein C-II and transthyretin. Compared with group I, the expression levels of complement component C4b in group III and apolipoprotein C-II in group II were up-regulated (1.352 88-fold, 1.512 14-fold, respectively); compared with group I, the expression levels of apolipoprotein A-I, apolipoprotein C-III and transthyretin in group II were down-regulated (1.601 17-fold, 1.034 49-fold, 1.313 35-fold, respectively).</p><p><b>CONCLUSION</b>The findings of this study show that most of the identified differential proteins are closely related to immunity and liver dysfunction, which provides some evidence on elucidating the mechanisms and screening of biomarkers of TCE intoxication.</p>

Pathological analysis and mRNA expression of apoptosis genes in rat kidney tissue after subacute melamine treatment / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>to investigate pathological changes and mRNA expression of apoptosis genes bcl-2, bax and Caspase-3 in rat kidney tissue after rats are administrated with melamine for 28 days.</p><p><b>METHODS</b>10 male SD rats and 10 female SD rats in each group were administrated with three doses of melamine (low dose, middle dose, high dose) by gavage for 28 days. The animals were divided into three experimental groups and one control group. The doses for male rats were 200, 400, 800 mg/kg, but for female rats they were 150, 300, 600 mg/kg. After melamine treatment the animals were sacrificed and the kidneys were taken out for pathological analysis and for detecting mRNA expression of bcl-2, bax and Caspase-3 with fluorescent quantitative PCR assay.</p><p><b>RESULTS</b>the tubular cylinders were observed in three experimental groups. The positive rates of tubular cylinders in three groups (from low dose to high dose) were 11/20, 13/20, 16/20, respectively. Additionally, melamine induced a significant decrease in mRNA expression of bcl-2 at low dose, middle dose or high dose, bcl-2 expression decreased by 20.58% - 49.51% in three groups treated with melamine. Furthermore, bax mRNA levels increased by 44.66% - 300.96% in groups treated with three doses of melamine, and Caspase-3 mRNA levels increased by 64.76% - 360.75% in groups treated with three doses of melamine.</p><p><b>CONCLUSIONS</b>melamine could induce pathological changes of rat kidneys, and it also induces a significant alteration of apoptosis Bcl-2, Bax and Caspase-3 mRNA expression in rat kidney tissue.</p>

Association of cooking oil fumes exposure and oxidative DNA damage among occupational exposed populations / 中华劳动卫生职业病杂志

<p><b>BACKGROUND</b>Previous investigations indicate that cooks are exposed to polycyclic aromatic hydrocarbons (PAH) from cooking oil fumes (COF). However, Emission of PAH and their carcinogenic potencies from cooking oil fumes sources have not been investigated among cooks.</p><p><b>AIMS</b>To investigate the urinary excretion of a marker for oxidative DNA damage, 8-hydroxydeoxyguanosine (8-OHdG), in different groups of cooks and different exposure groups, and to study the association between 8-OHdG and 1-hydroxypyrene (1-OHP), a biological marker for PAH exposure.</p><p><b>METHODS</b>Urine samples were collected from different groups of cooks (n = 86) and from unexposed controls (n = 36), all are male with similar age and smoking habits. The health status, occupational history, smoking, and alcohol consumption 24 hours prior to sampling was estimated from questionnaires. The urinary samples were frozen for later analyses of 8-OHdG and 1-OHP by high performance liquid chromatography.</p><p><b>RESULTS</b>Excretion in urine of 8-OHdG were similar for controls (mean 1.2 µmol/mol creatinine, n = 36), and for those who had been in the kitchen room with exhaust hood operation (mean 1.5 µmol/mol creatinine, n = 45). COF exposed cooks without exhaust hood operation had increased excretion of 8-OHdG (mean 2.3 µmol/mol creatinine, n = 18). The difference between this group and the unexposed controls was significant. The urinary levels of ln 1-OHP and ln 8-OHdG were still significantly correlated in a multiple regression analysis.</p><p><b>CONCLUSION</b>Results indicate that exposure to PAH or possibly other compounds in COF may cause oxidative DNA damage.</p>

Effect of cadmium chloride on the expression and phosphorylation of mitogen-activated protein kinase in normal rat kidney epithelial cells / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the effect of cadmium chloride on the expression and phosphorylation of mitogen-activated protein kinase (MAPK) in normal rat kidney epithelial (NRK) cells.</p><p><b>METHODS</b>The NRK cells were incubated with cadmium chloride either at respective dose (0, 1, 5, 10, 20, 40 µmol/L) for 24 h or at same dose (10 µmol/L) for respective time (0, 0.5, 1.0, 2.0, 4.0, 8.0 h). Western blotting was applied to test the expression of MAPK in NRK cells (ERK1/2, p38, JNK); and phosphor-specific antibody to detect the phosphorylated MAPK (p-ERK1/2, p-p38, p-JNK).</p><p><b>RESULTS</b>There was no significant difference in the MAPK expression among the groups either treated with different doses or for different time; however, the level of phosphorylated MAPK was comparatively higher than it in control group. There was an obvious expression of p-ERK1/2 at 1.00 ± 0.06 in the group incubated with 10 µmol/L CdCl(2); and the expression in the 20 µmol/L and 40 µmol/L CdCl(2) group was 2.58 ± 0.11, 2.76 ± 0.23 respectively, which was 1.58 and 1.76 times more than it in 10 µmol/L CdCl(2) group. The differences were statistically significant (F = 827.70, P < 0.01). The respective expression of p-p38MAPK in the 20 µmol/L (2.47 ± 0.20)and 40 µmol/L CdCl(2) group (3.73 ± 0.25)was 1.47 and 2.73 times more than it in control group (1.00 ± 0.02), and the differences were also statistically significant (F = 280.06, P < 0.01). There was a dose-effect relationship of the concentration of cadmium in the expression of p-ERK1/2 (r = 0.919, t = 4.69, P = 0.009) and p-p38MAPK (r = 0.945, t = 5.79, P = 0.004). Additionally, phosphorylated MAPK expressed in a time-dependent manner. The expression of p-ERK1/2 was obvious in the group incubated for 1 h (1.26 ± 0.11), and the respective expression in the 4 h group (1.51 ± 0.07) and 8 h group (3.53 ± 0.23) was 1.5 and 3.5 times of it in the control group (1.00 ± 0.02). The differences were statistically significant (F = 427.82, P < 0.001). The expression of p-p38MAPK increased significantly in 1 h group (1.31 ± 0.07); while the respective expression in 4 h group (3.53 ± 0.32) and 8 h group (4.41 ± 0.38) was 3.5 and 4.4 times of it in control group (1.00 ± 0.03). The differences were also statistically significant (F = 280.06, P < 0.001).</p><p><b>CONCLUSION</b>Cadmium chloride could significantly enhance the phosphorylation of MAPK in NRK cells; and it is probably associated with the activation of MAPK.</p>

Study on skin sensitization as well as liver and kidney impairment in guinea pigs treated with trichloroethylene / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study skin sensitization as well as liver and kidney impairment in guinea pigs treated with trichloroethylene (TCE).</p><p><b>METHODS</b>Guinea pig maximization test (GPMT) was applied in this study, guinea pigs were divided into 3 groups, namely negative control, positive control and TCE treatment. Animals of 3 groups were administrated with olive oil, 2, 4-dinitrochlorobenzene (DNCB), and TCE, respectively, by intradermal injection. The animal skin was observed and blood was collected after various treatment, the liver function tests were conducted, including detection of activities of ALT, AST, LDH and levels of creatinine, uric acid, and urea with automatic biochemical analyzer.</p><p><b>RESULTS</b>Obvious skin impairment was observed in the groups of positive control and TCE treatment, the skin impairment included erythema and edema, the sensitization rate was 100% in positive control and 83.3% in TCE treatment group. Additionally, the activities of ALT, AST and LDH increased significantly in the groups of positive control and TCE treatment when compared with the negative control.</p><p><b>CONCLUSIONS</b>Trichloroethylene is one of the strong hypersensitizing substances, it could induce skin allergic reaction and liver impairment in guinea pigs.</p>

Relationship between gene polymorphism of CYP2E1, CYP1A1, IL-4 and medicamentosa-like dermatitis induced by trichloroethylene / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the relationship between gene polymorphism of CYP2E1, CYP1A1, IL-4 and susceptibility of medicamentosa-like dermatitis induced by trichloroethylene (TCE).</p><p><b>METHODS</b>35 patients with medicamentosa-like dermatitis induced by TCE were chosen as the patient group, and 35 healthy workers as control group. The real-time quantitative polymerase chain reaction (PCR) with TaqMan minor groove binding (MGB) probes was used to test single nucleotide polymorphisms (SNP) of CYP2E1, CYP1A1 and IL-4 in the patients with medicamentosa-like dermatitis as well as in the control. The genotypes and the frequency of genotype or allele were compared between the patients and control with statistical analysis.</p><p><b>RESULTS</b>The frequency of allele G within CYP1A1 gene (rs1048943) was significantly higher in TCE patients (37.1%) than that in control (P<0.05); the frequency of allele T within CYP2E1-1053 C/T was significantly higher in TCE patients (41.4%) than that in control (P<0.01); the frequency of T/T within IL-4-588 C/T (rs2243250) was significantly higher in TCE patients (75.0%) than that in control (P<0.01), and the frequency of allele T within IL-4-588 C/T (rs2243250) was also significantly higher in TCE patients (87.5%) than that in control (P<0.01).</p><p><b>CONCLUSION</b>The gene polymorphism of CYP2E1, CYP1A1, IL-4 is probably associated with hypersensitivity for the TCE patients with medicamentosa-like dermatitis, and could be one of the genetic factors related to the individual susceptibility to TCE exposure.</p>

Study on the relationship between breast cancer resistance protein expression and 5-fluorouracil resistance / 中华预防医学杂志

<p><b>OBJECTIVE</b>To screen breast cancer resistance protein BCRP-mediated resistance agents and to investigate the relations between BCRP expression and drug resistance.</p><p><b>METHODS</b>MT assay was performed to screen BCRP-mediated resistant agents with established BCRP expression cell model. While, the high performance liquid chromatography (HPLC) assay was administrated to measure the related dosage of intracellular retention resistant agents. The BCRP expression was investigated by both real-time RT-PCR and immunohistochemistry (IHC) assay in 140 clinical breast cancer tissue specimens. Chemosensitivity to resistant agents for clinical breast cancer tissue specimens was analyzed by MT assay. The Nonparametric variance statistics method was used to analyze the correlations between clinical breast cancer tissue of BCRP expression and drug resistance.</p><p><b>RESULTS</b>MT assay showed that increasing resistance of 5-fluorouracil (5-Fu) climbed with the increases of the BCRP expressions by 10.58 times (P < 0.05, n = 3) in cell model. HPLC assay also proved that a significant negative correlation between the intracellular retention dose of 5-Fu with different expression of BCRP (r = -0.897, P < 0.05, n = 3). Forty-seven tissue specimens of BCRP-positive expression were rapidly determined by using both real-time RT-PCR and IHC in 140 clinical breast cancer tissue specimens. Subsequently, the resistance index (RI) for 47 BCRP-positive clinical breast cancer tissues to 5-Fu was shown from 7 to 12 times compared with normal cancer-side tissues through MT assay. The statistical correlation between BCRP expression and 5-Fu resistance was observed in clinical breast cancer tissue specimens (R2 = 0.8124, P < 0.01).</p><p><b>CONCLUSION</b>This study results showed that there is a significant relationship between BCRP expression and 5-Fu resistance. Moreover, the results suggest that the chemotherapy scheme could be optimized on BCRP-positive expression breast cancer patients.</p>

Growth inhibition and apoptosis of human colon cancer cells induced by vitamin E succinate / 第二军医大学学报

Objective: To investigate the growth inhibition and apoptosis induction effect of vitamin E succinate (VES) on human colon cancer cells and to analyze the modulation of apoptosis-mediator Fas expression in this process. Methods: Human colon cancer cell line LS174T was treated with VES for 12 h, 24 h and 48 h at the concentrations of 5 mg/L, 10 mg/L and 20mg/L. 1-(4,5-dimethylthiazo-2-yl)-3,5-diphenylformazan (MTT) assay was employed to detect the inhibitory effect of VES on the growth of colon cancer cells. Flow cytometry was then used to analyze the cell cycle of the colon cancer cells after being treated with VES and the apoptotic rate was calculated at the same time. To find out whether the Fas protein expression was modulated in this process, Western blotting assay and flow cytometry were used to detect the Fas protein level in whole cell lystates and on cell surface. Results: VES exhibited a significant inhibitory effect on the growth of human colon cancer cells in a doseand time-dependent manner. After being treated with VES at 5 mg/L, 10 mg/L and 20 mg/L for 48 h, the apoptotic rate of LS174T cells rose from 0.90% to 15.9%, 46.7% and 64.5%, respectively. Fas neutralizing antibody can significantly block VES-induced apoptosis. After the administration of VES, total Fas protein in whole-cell extracts increased in a dose-dependent manner. The flow cytometry showed that the mean fluorescence intensity rose from 5.43 to 9.88, 13.21 and 18.0 after being treated with VES. Conclusion: VES can induce significant growth inhibition and apoptosis in human colon cancer cells. The modulation of Fas expression is one of the mechanisms involved in this process and may be related to the upregulation of Fas molecule on the cancer cell surface.

Growth inhibition and apoptosis of human colon cancer cells induced by vitamin E succinate / 第二军医大学学报

Objective: To investigate the growth inhibition and apoptosis induction effect of vitamin E succinate (VES) on human colon cancer cells and to analyze the modulation of apoptosis-mediator Fas expression in this process. Methods: Human colon cancer cell line LS174T was treated with VES for 12 h, 24 h and 48 h at the concentrations of 5 mg/L, 10 mg/L and 20mg/L. 1-(4,5-dimethylthiazo-2-yl)-3,5-diphenylformazan (MTT) assay was employed to detect the inhibitory effect of VES on the growth of colon cancer cells. Flow cytometry was then used to analyze the cell cycle of the colon cancer cells after being treated with VES and the apoptotic rate was calculated at the same time. To find out whether the Fas protein expression was modulated in this process, Western blotting assay and flow cytometry were used to detect the Fas protein level in whole cell lystates and on cell surface. Results: VES exhibited a significant inhibitory effect on the growth of human colon cancer cells in a doseand time-dependent manner. After being treated with VES at 5 mg/L, 10 mg/L and 20 mg/L for 48 h, the apoptotic rate of LS174T cells rose from 0.90% to 15.9%, 46.7% and 64.5%, respectively. Fas neutralizing antibody can significantly block VES-induced apoptosis. After the administration of VES, total Fas protein in whole-cell extracts increased in a dose-dependent manner. The flow cytometry showed that the mean fluorescence intensity rose from 5.43 to 9.88, 13.21 and 18.0 after being treated with VES. Conclusion: VES can induce significant growth inhibition and apoptosis in human colon cancer cells. The modulation of Fas expression is one of the mechanisms involved in this process and may be related to the upregulation of Fas molecule on the cancer cell surface.

Two-dimensional electrophoresis and mass spectrometry analysis on effects of trichloroethylene on protein of L-02 liver cells / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the effects of trichloroethylene (TCE) on the protein in L-02 cells in vitro.</p><p><b>METHODS</b>Thiazolyl blue and Trypan blue tests were used to investigate the cytotoxicity of TCE to L-02 liver cell. The 2-D electrophoresis was used to analyse the expression of proteins in L-02 liver cells. The differentially expressed protein spots were identified by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-TOF-MS).</p><p><b>RESULTS</b>When the concentration of TCE exceeded 30 micromol/L, there was distinct cytotoxicity to L-02 cell (P < 0.05). Selected 40 micromol/L to treat L-02 liver cells and analyze the differential proteome expression, the results showed that the expression level of 37 protein spots was up-regulated and 15 protein spots was down-regulated. And 15 proteins were identified by MALDI-TOF-TOF-MS.</p><p><b>CONCLUSION</b>TCE can change the proteome expression of L-02 liver cell. It should provide the fundamental information to identify proteins related to TCE in further study.</p>