OBJECTIVETo explore the effect of miR-542-3p in malignant transformation of human bronchial epithelial cells (16HBE) induced by anti-benzo(a)pyrene-7,8-diol-9,10-epoxide (anti-BPDE).

METHODSThe relative expression level of mature miR-542-3p in transformed cells (16HBE-T) and untransformed control cells (16HBE-N) was measured by real-time quantitative polymerase chain reaction (qRT-PCR). miRNA mimic was transiently transfected into 16HBE-T to change the expression level of miR-542-3p, and then the influenced changes of cell proliferation, cell cycle, apoptosis, and soft agar colony formation rate and the migration of transfected cells were analyzed.

RESULTSBefore transfection, the expression level of mature miR-542-3p in 16HBE-T was lower (39.08 ± 6.95)% than it in 16HBE-N (t = 15.18, P < 0.05). In comparison with the 16HBE-T group, the expression level of miR-542-3p in miR-542-3p mimic-transfected group was (5.23 ± 0.55) fold (t = 17.37, P < 0.05) after transfection. Cell proliferation of mimic-transfected group was decreased to (62.06 ± 5.61)% (t = -17.28, P < 0.05), percentage of cells in G(0)/G(1) phase up to (74.76 ± 4.86)% (t = 4.53, P < 0.05), rate of colony formation degrade to (5.87 ± 0.67)% (t = -6.66, P < 0.05), coverage areas ratio decreased to (0.31 ± 0.08) (t = -6.78, P < 0.05). There was no change with apoptosis.

CONCLUSIONOur studies showed that miR-542-3p played the role as a tumor suppressor, which led to a significant decrease in the proliferation capacity and degree of malignancy. These findings suggest aberrantly down-regulated miR-542-3p may be one critical factor that contributes to malignant transformation of 16HBE induced by anti-BPDE.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide ; adverse effects ; Bronchi ; cytology ; Cell Transformation, Neoplastic ; drug effects ; genetics ; metabolism ; Epithelial Cells ; cytology ; drug effects ; Humans ; MicroRNAs ; genetics ; Transfection

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide ; toxicity ; Carcinogens ; toxicity ; Cell Line, Tumor ; DNA Damage ; drug effects ; Dose-Response Relationship, Drug ; HSP70 Heat-Shock Proteins ; biosynthesis ; Humans

OBJECTIVETo study the inhibitory effect of chlorophyllin (CHL) on trans-benzo(a)pyrene-trans-7,8-dihydrodiol-9,10-epoxide (BPDE) induced malignant transformation in human bronchial epithelial cell line (16HBE).

METHODS10, 50 or 100 micro mol/L CHL were added into the media during the cells transformation induced by BPDE, and the malignant degree of transformed cells were identified by the ConA agglutination test and the assay for anchorage-independent growth and tumorigenicity.

RESULTSAfter the cells were cultured for 25 times, the time of cells agglutination in groups treated with both CHL and BPDE was increased significantly; the colony formation efficiency in soft agar in groups treated with both CHL and BPDE (7.4 per thousand, 11.4 per thousand and 14.4 per thousand ) showed significant decrease (P < 0.05) in dose-dependent manner, as compared with that in group treated with BPDE alone (19.6 per thousand ). Cells treated with both CHL and BPDE or BPDE alone developed tumor in nude mice, a squamous carcinoma confirmed by histopathological examination. The volume of tumor in groups treated with both CHL and BPDE (0.43 +/- 0.13) cm(2), (0.22 +/- 0.04) cm(2) and (0.10 +/- 0.06) cm(3) was significantly smaller (P < 0.05) and dose-dependent, as compared with that in the group treated with BPDE alone (1.71 +/- 0.37) cm(3).

CONCLUSIONCHL showed significant antitransforming ability in human bronchial epithelial cell line induced by BPDE.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide ; toxicity ; Animals ; Anticarcinogenic Agents ; pharmacology ; Cell Transformation, Neoplastic ; drug effects ; Chlorophyllides ; pharmacology ; Mice ; Mice, Inbred BALB C ; Neoplasms, Experimental ; prevention & control

OBJECTIVETo establish human bronchial epithelial cell lines over expressing oncogene and to investigate its application in detection of carcinogen-induced cell transformation.

METHODSMediated by retrovirus infection, human telomerase catalytic subunit, hTERT was introduced into immortal human bronchial epithelial cells (16HBE) and followed by introduction of the oncogenic allele H-Ras(V12), or c-Myc or empty vector, creating cell lines 16HBETR, 16HBETM and 16HBETV, respectively. Biological characteristics of these cell lines including morphology, proliferation, and chromosomal aberration were examined to access whether they were transformed. Soft agar experiment and nude mice subcutaneous injection were performed using pre-transformed 16HBE cells induced by known carcinogens, nickel sulfate (NiSO4) and 7, 8, -dihydrodiol-9, 10-epoxide benzo[a] pyrene (BPDE).

RESULTSWith detection of telomerase activity and Western blotting, the expression of target proteins was verified. Thus, the transgenic 16HBE cell lines were successfully established. Cells expressing oncogene H-Ras or c-Myc grew 30.3% or 10.4% faster than control cells. However, these cells failed to form colonies in soft agar or form tumor in nude mice. 16HBETR, 16HBETM cells obtained transformed phenotype at 5 wks, 11 wks, respectively after treatment with BPDE, which are 15 wks and 9 wks earlier than control cells 16HBETV (20 wks). Meanwhile, 16HBETR, 16HBETM cells obtained transformed phenotype at 11 wks, 14 wks, respectively after treatment with nickel sulfate, which are 21 wks and 18 wks earlier than control cells (32 wks).

CONCLUSIONWith the advantage of shorter latency, transgenic human cell transformation models could be used in potent carcinogen screening and applied to chemical-carcinogenesis mechanism study.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide ; toxicity ; Animals ; Carcinogenicity Tests ; Cell Line ; Cell Transformation, Neoplastic ; drug effects ; metabolism ; pathology ; Epithelial Cells ; Gene Expression ; Gene Expression Regulation ; Genes, myc ; Genes, ras ; Humans ; Mice ; Mice, Inbred BALB C ; Mice, Nude

OBJECTIVETo establish the stable inhibition of HER2/neu expression by vector-mediated small hairpin RNA in malignant transformed human bronchial epithelial cell line induced by anti-benzo(a)pyrene-trans-7, 8-dihydrodiol-9, 10-epoxide (anti-BPDE).

METHODSThe pSIREN-RetroQ-neu recombinant vector targeting HER2/neu was constructed and confirmed by restriction and sequencing analysis, then it was transfected into anti-BPDE malignant transformed 16HBE cells (16HBE-T) through lipofectamine 2000. The control groups included the 16HBE-T cells transfected with negative control vector (negative control) and 16HBE-T. The cells transfected with vectors were screened by puromycin. The HER2/neu mRNA and protein expressions in the vector-transfected 16HBE-T cells were detected by RT-PCR and Western blot method respectively.

RESULTSThe pSIREN-RetroQ-neu recombinant vector which inhibited HER2/neu mRNA and protein expressions in the 16HBE-T was constructed. The level of HER2/neu mRNA in the 16HBE-T cells transfected with pSIREN-RetroQ-neu was significantly reduced as compared to the negative control and blank control cells (0.114 +/- 0.003 vs.blank control 0.186 +/- 0.001, t = 39.154, P < 0.05; and negative control 0.182 +/- 0.015, t = 7.564, P < 0.05), while its level did not differ significantly between negative control cells and blank control of 16HBE-T (t = -0.409, P > 0.05). HER2/neu protein level in pSIREN-RetroQ-neu transfected cells was inhibited by 40% and 39% respectively.

CONCLUSIONPlasmid-based shRNA expression systems targeted against HER2/neu gene were generated successfully, which resulted in down-regulation of HER2/neu gene expression in the 16HBE-T efficiently.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide ; toxicity ; Base Sequence ; Cell Line, Transformed ; Epithelial Cells ; drug effects ; metabolism ; Gene Expression ; Genes, erbB-2 ; Humans ; Molecular Sequence Data ; RNA, Small Interfering ; Reverse Transcriptase Polymerase Chain Reaction ; Transfection

OBJECTIVETo investigate the application of BPDE-albumin adducts as monitoring biomarkers for coke oven workers exposed to polycyclic aromatic hydrocarbons (PAHs) and to explore possible relationship between BPDE-albumin adducts and urinary 1-hydroxypyrene (1-OHP) levels in them.

METHODSThirty-seven coke oven workers from a coke plant and 47 controls without the occupational exposure to PAHs were recruited in this study. The levels of plasma BPDE-albumin adducts and urinary 1-OHP were analyzed using high performance liquid chromatography.

RESULTSThe median levels of BPDE-albumin adducts (42.10 fmol/mg albumin) and urinary 1-OHP (5.46 micromol/mol creatinine) were significantly higher in coke oven workers than in controls (14.16 fmol/mg albumin, 2.96 micromol/mol creatinine, respectively; P<0.01). Multiple logistic regression analysis showed that coke oven workers were at higher risk of having BPDE-albumin adduct levels above 25.30 micromol/mg albumin (OR=1.79, P<0.01) and urinary 1-OHP levels above 4.13 micromol/mol creatinine (OR=2.45, P<0.05). There was a positive correlation between the levels of BPDE-albumin adducts and urinary 1-OHP in all subjects (rs=0.349, P<0.01).

CONCLUSIONBPDE-albumin adduct is a useful biomarker for monitoring long-term exposure to PAHs, and plasma BPDE-albumin adducts level is significantly correlated to urinary 1-OHP levels in coke oven workers.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide ; analysis ; Adult ; Coal Mining ; manpower ; Coke ; adverse effects ; Environmental Monitoring ; Humans ; Male ; Mutagens ; analysis ; Occupational Exposure ; Plasma ; chemistry ; Polycyclic Aromatic Hydrocarbons ; Pyrenes ; analysis ; Serum Albumin ; analysis ; Urinalysis ; Urine ; chemistry

OBJECTIVETo screen the over differentially expressed genes in carcinoma induced by BPDE-transformed 16HBE cells (16HBE-C cells).

METHODSThe suppression subtractive hybridization (SSH) method was performed to profile differentially expressed genes between 16HBE-C cells and 16HBE cells. The cDNA fragments of differentially expressed genes were inserted into TA cloning vector and transformed competent E. coli strain. Positive clones were randomly picked up and identified by the colony PCR method. Dot blot was used to test the same source with the tester. The differentially expressed cDNA fragments were sequenced and compared with known genes and EST database in Genbank.

RESULTSEight known genes were over-expressed in 16HBE-C cells including eukaryotic translation elongation factor 1 alpha 1, HIF-1 responsive RTP801, ribosomal protein L10 (RPL10), ribosomal protein S29 (RPS29), mitochondrion related genes, and laminin receptor 1. Three differentially expressed cDNA fragments could not be matched to the known genes but to the EST database.

CONCLUSIONThe SSH method can detect differentially expressed genes between 16HBE-C and 16HBE cells. BPDE-induced carcinogenesis may be related to alteration of at least eight known genes and three unknown genes. These expression data provide a clue to further cloning novel genes and studying functions in BPDE-induced carcinoma.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide ; pharmacology ; toxicity ; Carcinogens ; pharmacology ; toxicity ; Carcinoma ; genetics ; metabolism ; Cell Line ; Cell Line, Transformed ; Cell Transformation, Neoplastic ; chemically induced ; Gene Expression Regulation, Neoplastic ; Humans ; Nucleic Acid Hybridization ; methods ; Polymerase Chain Reaction ; RNA, Messenger ; metabolism

OBJECTIVETo investigate the effect of CYP1A1 and GSTM1 genetic polymorphisms and BPDE-DNA adducts on lung tumorigenesis.

METHODSThe case control study has included 200 cases of lung cancer and 200 controls. DNA was extracted from blood samples of all subjects. The genotype of both CYP1A1 and GSTM1 were detected with PCR-based restriction fragment length polymorphisms (PCR-RELP). BPDE-DNA adducts were detected with competitive ELISA.

RESULTSCYP1A1 mutant genotype and GSTM1 null genotype with smoke has increased the risk of lung cancer, with OR being 2.406(1.321-4.382), 2.755(1.470-5.163), respectively. The level of BPDE-DNA adducts in patients was greater than control, and the adduct level in ever smokers was higher than never smokers, the difference was statistically significant (P= 0.0252). GSTM1 null genotype individuals with BPDE-DNA level higher than 5 adducts/10(8) nucleotide have increased risk of lung cancer (OR= 1.988, 95%CI: 1.011-3.912). Compared with never smokers with CYP1A1 wild genotype, smokers with CYP1A1 mutation genotype had an increased risk of forming a higher level of DNA adducts (P= 0.0459). Smokers with GSTM1 null genotype formed more DNA adducts compared with never smokers with GSTM1 functional genotype (OR = 2.432, 95% CI: 1.072-4.517).

CONCLUSIONGSTM1 null genotype with higher level DNA adducts may increase the risk of lung cancer. DNA adducts form easier in smokers with CYP1A1 mutation genotype and GSTM1 null genotype, which in turn may influence lung tumorigenesis.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide ; Carcinogens ; Case-Control Studies ; Cytochrome P-450 CYP1A1 ; genetics ; DNA Adducts ; genetics ; Female ; Genotype ; Glutathione Transferase ; genetics ; Humans ; Lung Neoplasms ; chemically induced ; enzymology ; genetics ; Male ; Middle Aged ; Polymorphism, Genetic

OBJECTIVETo screen microRNA (miRNA) profiles of malignantly transformed cells induced by anti-benzo-a-pyrene-trans-7, 8-dihydrodiol-9, 10-epoxide (BPDE) and to look for miRNAs which is expressed differently between malignantly transformed cells and normal human bronchial epithelial cells 16HBE.

METHODSExperimental group was the malignantly transformed 16HBE which was induced by cultured with final concentration 2.0 micromol/L of BPDE which was dissolved in dimethyl sulphoxide. The control group was 16HBE that was cultured with minimal essential medium including dimethyl sulphoxide. 327 miR-NAs were tested be-tween those two groups with miRNA microarray analysis. MiR-10a that was down expressed and miR-320 that was overexpressed were selected to be validated by miRNA specific quantitative real-time reverse transcriptase chain reaction (miR qRT-PCR).

RESULTS327 human miRNAs were tested with miRNA microarray analysis. 55 miRNAs were found expressing differently between those two groups and of which 46 were overexpressed and 9 were down expressed. Some data were validated by quantitative RT-PCR.

CONCLUSIONmiRNAs expressed significantly between malignantly transformed 16HBE and normal cells and this helps us look for unique miRNAs of malignantly transformed cells induced by BPDE, but there should have more sufficient evidences to prove their functions in malignant cells.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide ; adverse effects ; Bronchi ; cytology ; Cell Transformation, Neoplastic ; chemically induced ; genetics ; pathology ; Cells, Cultured ; Epithelial Cells ; drug effects ; pathology ; Gene Expression Profiling ; Humans ; MicroRNAs ; genetics

OBJECTIVETo screen miRNA profiles of malignantly transformed human bronchial epithelial cells, 16HBE-T, induced by anti-benzo[a]pyrene-trans-7,8-diol-9,10-epoxide (anti-BPDE), and to analyze putative miR-10a targets in 16HBE-T.

METHODSA novel microarray platform was employed to screen miRNA profiles of 16HBE-T cells transformed by anti-BPDE. Microarray data for miR-10a and miR-320 were validated using quantitative real time polymerase chain reaction (QRT-PCR). The expression of a putative target for miR-10a, HOXA1, was analyzed by reverse transcription polymerase chain reaction (RT-PCR) and QRT-PCR.

RESULTSIn comparison with the vehicle-treated cells (16HBE-N), 16HBE-T exhibited differential expression of 54 miRNAs, in which, 45 were over-expressed and 9 were down-regulated. The five most highly expressed miRNAs were miR-494, miR-320, miR-498, miR-129, and miR-106a. The lowest expressed miRNAs were miR-10a, miR-493-5p, and miR-363*. Three members of miR-17-92 cluster, miR-17-5p, miR-20a, and miR-92, showed significantly higher abundance in 16BHE-T as miR-21, miR-141, miR-27a, miR-27b, miR-16 and miRNAs of the let-7 family. The putative target for miR-10a, HOXA1 mRNA was up-regulated 3-9-fold in 16HBE-T, as compared with 16HBE-N.

CONCLUSIONThe findings of the study provide information on differentially expressed miRNA in malignant 16HBE-T, and also suggest a potential role of these miRNAs in cell transformation induced by anti-BPDE. HOXA1 is similarly up-regulated, suggesting that miR-10a is associated with the process of HOXA 1-mediated transformation.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide ; toxicity ; Carcinogens ; toxicity ; Cell Transformation, Neoplastic ; chemically induced ; genetics ; metabolism ; Cells, Cultured ; Gene Expression Profiling ; Homeodomain Proteins ; genetics ; metabolism ; Humans ; MicroRNAs ; metabolism ; Oligonucleotide Array Sequence Analysis ; RNA, Messenger ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Transcription Factors ; genetics ; metabolism