Bronchi ; drug effects ; pathology ; Cell Line ; Cell Transformation, Neoplastic ; drug effects ; genetics ; Dust ; Epithelial Cells ; drug effects ; pathology ; Gene Library ; Humans ; Minerals ; toxicity

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

OBJECTIVETo investigate the expression and gene mutation of cluster of differentiation 9 (CD9) in the pathway of the mineral powder induced malignant transformation in immortalized human bronchial epithelial cells (BEAS-2B) in Gejiu.

METHODSBEAS-2B cells served as the control group and its malignant transformation cells induced by mineral powder in Gejiu were considered as experiment group. The expression of CD9 protein in 20 bottles of BEAS-2B cells and 20 bottles of malignant transformation cells was evaluated by immunocytochemistry. The mRNA expression of CD9 in 10 bottles of BEAS-2B cells and 10 bottles of malignant transformation cells was examined by reverse transcriptase polymerase chain reaction (RT-PCR). Gene mutation was detected in the products of RT-PCR by DNA sequencing.

RESULTSThere was significant difference between the expression of CD9 protein in BEAS-2B cells (100%, 20/20) and that in its malignant transformation cells (35%, 7/20 P < 0.01). The expression of CD9 mRNA in BEAS-2B cells 0.91 +/- 0.09 was significantly higher than that in its malignant transformation cells (0.34 +/- 0.14) (P < 0.01). Two point mutation of CD9 gene was detected in the malignant transformation cells of BEAS-2B by DNA sequencing. The change of G-->T in the base of 231 led to the change of Gln-->His in the amino acids of 40. The change of T-->A in the base of 119 led to the change of Val-->Asp in the amino acids of 3.

CONCLUSIONThe absence or down-regulation of CD9 expression and point mutation in the malignant transformation cells of BEAS-2B may play a considerable role in the pathway of the malignant transformation in the BEAS-2B cells induced by mineral powder in Gejiu.

Bronchi ; pathology ; Cell Line ; Cell Transformation, Neoplastic ; drug effects ; genetics ; Dust ; Epithelial Cells ; drug effects ; metabolism ; pathology ; Gene Expression Regulation ; drug effects ; Humans ; Lung Neoplasms ; chemically induced ; genetics ; metabolism ; pathology ; Mining ; Mutation ; drug effects ; Tetraspanin-29 ; genetics ; metabolism

OBJECTIVETo clone differentially expressed cDNA sequences involved in malignant transformation induced by benzo(a)pyrene metabolite dihydroxyepoxy benzo pyrene (BPDE).

METHODThe malignant transformation of human bronchial epithelial cell line 16HBE induced by BPDE in vitro was used as a model for comparing gene expression between the transformed cells and controls. cDNA representational difference analysis (cDNA-RDA) was performed to isolate differentially expressed cDNA fragment in transformed cells. The cDNA fragments were ligated to pGEM-T vector and transformed into JM109 bacteria. The plasmid DNA were sequenced and compared with data in GenBank by BLASTN.

RESULTSFive cDNA sequences were found to be novel ones and were registered in dbest database, which assigned accession numbers in GenBank are BG354691, BG354692, BG354693, BG354694 and BG354695, respectively. Eight of the remaining cDNA sequences showed sequence homology to those previously reported such as ribosomal protein S23, MLN137, ACTN4, transforming growth factor and G protein gene.

CONCLUSIONSThese 13 genes may be involved in BPDE-induced malignant transformation, but their biological characteristics and functions are left to further studies.

Benzopyrenes ; metabolism ; pharmacology ; Carcinogens ; pharmacology ; Cell Transformation, Neoplastic ; chemically induced ; genetics ; Cells, Cultured ; Cloning, Molecular ; DNA, Complementary ; analysis ; drug effects ; DNA, Neoplasm ; analysis ; Gene Expression ; drug effects ; Humans

OBJECTIVE: To investigate the effect of methylation transferase inhibitor 5-aza-2'-deoxycitydine (5-aza-2 dC) on the growth, differentiation and apoptosis of human acute myeloid leukemia(AML) cell line HL-60, and to explore the possible anti-leukemia mechanism of 5-aza-2 dC. METHODS: HL-60 cells were treated by 5-aza-2 dC at various concentrations for different periods of time. The effect of 5-aza-2 dC on the growth of HL-60 cells were detected by MTT assay. The effect on the cell cycle and differentiation were detected by flow cytometry. The effect on the apoptosis were detected by Hochest33342 staining and flow cytometry. The expression of S100A8 and S100A9 was detected by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: (1) 5-aza-2 dC inhibited the growth of HL-60 cells in a concentration- and time-dependent manner, and HL-60 cells were arrested at G2/M phases; (2) 5-aza-2 dC enhanced the expression of cell differentiation antigen CD11b at HL-60 cells, especially at the low drug concentration; (3) 5-aza-2 dC induced HL-60 cell apoptosis in a concentration- and time-dependent manner, especially at the high drug concentration; (4) 5-aza-2 dC increased the expression levels of S100A8 and S100A9 mRNA in HL-60 cells. CONCLUSION 5-aza-2 dC can inhibit the growth of HL-60 cells accompanied with G2/M phase arrest, induce the differentiation and apoptosis of the cells, and increase the expression levels of S100A8 and S100A9 mRNA, which may be the anti-AML mechanism of 5-aza-2 dC.
Antimetabolites, Antineoplastic ; pharmacology ; Apoptosis ; drug effects ; Azacitidine ; analogs & derivatives ; pharmacology ; Calgranulin A ; biosynthesis ; genetics ; Calgranulin B ; biosynthesis ; genetics ; Cell Proliferation ; drug effects ; Cell Transformation, Neoplastic ; drug effects ; Decitabine ; HL-60 Cells ; Humans ; RNA, Messenger ; biosynthesis ; genetics

Traditional theories suggest that tumor growth occurs when all tumor cells work together and result in proliferation, so treatment has been mainly directed against the majority of the cells in tumor tissue, which often relapse, metastasize, and lead to treatment failure. As cancer stem cells have been successfully isolated from different tumor tissues, in-depth study of their function in relation to traditional cancer treatment faces enormous challenges. At the same time, a new theoretical basis has been provided for the in-depth study of tumorigenesis and the evaluation of prognosis of cancer therapy. Also, new ideas have been introduced for cancer therapy. Therefore, radical treatment of cancer can be achieved through killing cancer stem cells. This article reviews the research progress on cancer stem cells and their drug resistance.
ATP-Binding Cassette Transporters ; metabolism ; Animals ; Antineoplastic Agents ; pharmacology ; Apoptosis ; Cell Hypoxia ; Cell Transformation, Neoplastic ; DNA Repair ; DNA, Neoplasm ; genetics ; Drug Resistance, Multiple ; Drug Resistance, Neoplasm ; Humans ; Neoplasms ; genetics ; metabolism ; pathology ; Neoplastic Stem Cells ; drug effects ; pathology

OBJECTIVETo study the alternative expression and sequence of human elongation factor-1 delta (human EF-1 delta p31) during malignant transformation of human bronchial epithelial cells induced by cadmium chloride (CdC12) and its possible mechanism.

METHODSTotal RNA was isolated at different stages of transformed human bronchial epithelial cells (16HBE) induced by CdCl2 at a concentration of 5.0 microM. Special primers and probe for human EF-1 delta p31 were designed and expression of human EF-1 delta mRNA from different cell lines was detected with fluorescent quantitative PCR technique. EF-18 cDNA from different cell lines was purified and cloned into pMD 18-T vector followed by confirming and sequencing analysis.

RESULTSThe expressions of human EF-1 beta p31 at different stages of 16HBE cells transformed by CdCl2 was elevated (P < 0.01 or P < 0.05). Compared with their corresponding non-transformed cells, the overexpression level of EF-1 delta p31 was averagely increased 2.9 folds in Cd-pretransformed cells, 4.3 folds in Cd-transformed cells and 7.2 folds in Cd-tumorigenic cells. No change was found n the sequence of overexpressed EF-1beta p31 at different stages of 16HBE cells transformed by CdCl2.

CONCLUSIONOverexpression of human EF-1beta p31 is positively correlated with malignant transformation of 16HBE cells induced by CdC12, but is not correlated with DNA mutations.

Cadmium Chloride ; Cell Line ; Cell Transformation, Neoplastic ; chemically induced ; metabolism ; Epithelial Cells ; drug effects ; metabolism ; pathology ; Gene Expression Regulation, Neoplastic ; Humans ; Peptide Elongation Factor 1 ; genetics ; metabolism ; Respiratory Mucosa ; drug effects ; metabolism ; pathology ; Sequence Analysis, DNA

OBJECTIVETo study the oncogenic potential of mouse translation initiation factor 3 (TIF3) and elongation factor-1delta (TEF-1delta) in malignant transformed human bronchial epithelial cells induced by crystalline nickel sulfide (NiS).

METHODSAbnormal expressions of human TIF3 and TEF-1delta genes in two kinds of NiS-transformed cells and NiS-tumorigenic cell lines were investigated and analyzed by the reverse transcript polymerase chain reaction (RT-PCR) and fluorescent quantitative polymerase chain reaction (FQ-PCR), respectively.

RESULTSRT-PCR analysis primarily showed that both human TIF3 and TEF-1delta mRNA expressions in two kinds of NiS-transformed cells and NiS-tumorigenic cell lines were increased as compared with controls. FQ-PCR assay showed that the levels of TIF3 expressions in the transformed cells and tumorigenic cells were 3 and 4 times higher respectively, and the elevated expressions of TEF-1delta cDNA copies were 2.7- to 3.5-fold in transformed cells and 4.1- to 5.2-fold in tumorigenic cells when compared with non-transformed cells, indicating that the over-expressions of human TIF3 and TEF-1delta genes were related to malignant degree of the cells induced by nickel.

CONCLUSIONSThese findings demonstrate that there are markedly abnormal expressions of TIF3 and TEF-1delta genes during malignant transformation of human bronchial epithelial cell lines induced by crystalline NiS. They seem to be the molecular mechanisms potentially responsible for human carcinogensis due to nickel.

Biomarkers ; Bronchi ; cytology ; Cell Line, Transformed ; Cell Line, Tumor ; Cell Transformation, Neoplastic ; metabolism ; DNA, Complementary ; metabolism ; Epithelial Cells ; Gene Expression Regulation, Neoplastic ; drug effects ; Humans ; Nickel ; toxicity ; Peptide Elongation Factor 1 ; genetics ; metabolism ; Prokaryotic Initiation Factor-3 ; genetics ; metabolism

OBJECTIVETo explore the role of telomerase in asbestos dust induced malignant transformation of human embryonic lung fibroblasts in vitro.

METHODSHuman telomerase catalytic subunit (hTERT) was transferred into human embryonic lung fibroblasts (HELF). Chrysotile dust at concentration of 2.5 microg/cm(2) was added to HELF transduced with and without hTERT (HELF-T+), respectively, and their transduced foci were separated. Biological characteristics of the cells, telomerase activity, length of telomere and cell growth curve were observed. Colony forming test was performed on soft agar to evaluate the nature of transformation.

RESULTSThe hTERT gene was transferred into HELF steadily, and HELF-T+ was established. Malignant transformation occurred in both HELF and HELF-T+ by asbestos stimulation. Asbestos dusts could induce higher rate of transformations in HELF-T+ [(2.08 +/- 1.08)/utensil] than in HELF [(1.08 +/- 0.10)/utensil], P < 0.05. Telomerase activity in both transformed malignant cells and HELF-T+ was higher, as well as the longer length of telomere in them.

CONCLUSIONRate of malignant transformation in cells with more activity of telomerase and longer length of the telomere was higher after stimulation with asbestos, indicating telomerase could play an important role in asbestos induced human cells malignant transformation.

Asbestos, Serpentine ; toxicity ; Cell Transformation, Neoplastic ; drug effects ; Cells, Cultured ; DNA-Binding Proteins ; Embryo, Mammalian ; Fibroblasts ; pathology ; Gene Transfer Techniques ; Humans ; Lung ; pathology ; Telomerase ; genetics ; metabolism

The human basic Krüppel-like factor (hBKLF) is a newly cloned human transcription factor from the cDNA library of fetal liver. It belongs to the Krüppel-like transcription factor family. Previous expression study showed that it is a hematopoietic related factor. This study was aimed to investigate the effect of hBKLF on cell proliferation, differentiation and hemoglobin synthesis by using K562 cell line as model. The sense and antisense expression plasmids of hBKLF were constructed, and transfected into K562 cells by lipofectamine. After G418 selection for 4 weeks, the cell line with stable expression of the gene was obtained. Then the hBKLF expression level, proliferation ability, colony formation and hemoglobin production were detected by RT-PCR and Western blot, MTT method, methyl cellulose semisolid culture method and benzidine test respectively. The morphologic change of cell was observed with inverted microscope. The results showed that the sense plasmid could increase hBKLF level and antisense plasmid could decrease hBKLF expression. When hBKLF level was down-regulated, K562 cells could proliferate more quickly and synthesize more hemoglobin. But there were no differences in colony formation ability and no apparent morphologic change. It is concluded that hBKLF can inhibit hematopoietic cell proliferation and hemoglobin synthesis. It is suggested that hBKLF plays an important role in the proliferation and differentiation of hematopoietic cells.
Animals ; COS Cells ; Cell Differentiation ; physiology ; Cell Proliferation ; drug effects ; Cell Transformation, Neoplastic ; drug effects ; Cercopithecus aethiops ; Hemoglobins ; biosynthesis ; Humans ; K562 Cells ; Kruppel-Like Transcription Factors ; biosynthesis ; genetics ; pharmacology ; Transcription Factors ; biosynthesis ; genetics ; Transfection