Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
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Drug
Enzyme
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Query: UMLS:C0268596 (
EMA
)
2,520
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Estrogens are considered to play a major role in promoting the proliferation of both the normal and the neoplastic breast epithelium. Their role as breast carcinogens has long been suspected and recently confirmed by epidemiological studies. Three major mechanisms are postulated to be involved in their carcinogenic effects: stimulation of cellular proliferation through their receptor-mediated hormonal activity, direct genotoxic effects by increasing mutation rates through a cytochrome P450-mediated metabolic activation, and induction of aneuploidy. Recently it has been fully demonstrated that estrogens are carcinogenic in the human breast by testing in an experimental system the natural estrogen 17beta-estradiol (E(2)) by itself or its metabolites 2-hydroxy, 4-hydroxy, and 16-a-hydroxy-estradiol (2-OH-E(2), 4-OH-E(2), and 16-alpha-OH E(2)), respectively, by inducing neoplastic transformation of human breast epithelial cells (HBEC) MCF-10F in vitro to a degree at least similar to that induced by the chemical carcinogen benz(a)
pyrene
(BP). Neither Tamoxyfen (TAM) nor ICI-182,780 abrogated the transforming efficiency of estrogen or its metabolites. The E(2) induced expression of anchorage independent growth, loss of ductulogenesis in collagen, invasiveness in Matrigel, is associated with the loss of 9p11-13 and only invasive cells that exhibited a 4p15.3-16 deletion were tumorigenic. Tumors were poorly differentiated ER-alpha and progesterone receptor negative adenocarcinomas that expressed keratins,
EMA
and E-cadherin. The E(2) induced tumors and tumor-derived cell lines exhibited loss of chromosome 4, deletions in chromosomes 3p12.3-13, 8p11.1-21, 9p21-qter, and 18q, and gains in 1p, and 5q15-qter. The induction of complete transformation of the human breast epithelial cell MCF-10F in vitro confirms the carcinogenicity of E(2), supporting the concept that this hormone could act as an initiator of breast cancer in women. This model provides a unique system for understanding the genomic changes that intervene for leading normal cells to tumorigenesis and for testing the functional role of specific genomic events taking place during neoplastic transformation.
...
PMID:The role of estrogen in the initiation of breast cancer. 1711 77
The goal of this study was to determine the effects of tobacco compounds on gene expression in a human fetal lung cell line (WI38). In the present study, we investigated the effects of tobacco compounds (nicotine, benzo(a)
pyrene
(B(a)P), and 2-Naphthylamine) on gene expression profiles in human fetal fibroblasts using cDNA microarray and real-time PCR. WI38 cells were cultured in Eagle's minimum essential medium (MEM) supplemented with 10% fetal bovine serum, 2% 200 mM L-glutamine, and a 2% penicillin and streptomycin solution. Tissue culture flasks (T-25 cm(2)) containing confluent lung fibroblasts were incubated at 37 degrees C for 24 h with 5 mL of medium supplemented with 10 microM of a tobacco compound (nicotine, B(a)P, or 2-Naphthylamine). The gene expression profiles for the W138 cells varied depending on the tobacco compound. The cDNA microarray analysis revealed that apoptosis-related genes such as DNASE2,
MADD
, MST1, NME3, RARG, TNFRSF1A, BAD, and DFFB genes were down-regulated in tobacco compound-treated WI38 cells. We also observed significant increases in Arnt gene expression by real-time PCR in tobacco compound-treated WI38 cells. Tobacco compounds can affect apoptosis, immunity, and growth in WI38 cells. A microarray-based genomic survey is a high-throughput approach for the evaluation of gene expression in cell lines treated with tobacco compounds.
...
PMID:Effects of tobacco compounds on gene expression in fetal lung fibroblasts. 1824 14