Biochemical and Biophysical Research Communications
Preferential inducibility of CYP1A1 and CYP1A2 by TCDD: Differential regulation in primary human hepatocytes versus transformed human cells☆
Section snippets
Materials and methods
Cell culture and treatment. HepG2, LS174T, and MCF-7 cells (American Type Culture Collection, Manassas, VA) were cultured in Dulbecco’s modified Eagle’s medium containing 10% fetal bovine serum and transferred to hepatocyte culture medium as used for primary hepatocytes (In Vitro Technologies, Baltimore, MD). Two days later when the cells grew to cover approximately 75% of the well surface, the treatment was initiated. Primary cultures of hepatocytes (In Vitro Technologies, Baltimore, MD,
Cell type-preferred TCDD inducibility in enzyme activity
The activities of CYP1A1 and CYP1A2 were unambiguously determined in cultured cells applying the quantitative LC/MS/MS method for warfarin metabolic profiling [21]. Although both convert R-warfarin to 6-hydroxywarfarin and 8-hydroxywarfarin, CYP1A1 has a slight preference for forming 8-hydroxywarfarin while CYP1A2 dominantly forms 6-hydroxywarfarin [14]. In initial experiments, we repeatedly observed distinct R-warfarin metabolic profiles in primary human hepatocytes and HepG2 cells following
Acknowledgment
We thank B. King for her technical assistance.
References (30)
- et al.
Ah receptor ligands and tumor promotion: survival of neoplastic cells
Toxicol. Lett.
(2000) - et al.
Estrogen does not inhibit 2,3,7,8-tetrachlorodibenzo-p-dioxin-mediated effects in MCF-7 and Hepa 1c1c7 cells
J. Biol. Chem.
(1997) - et al.
The relative susceptibility of animals and humans to the carcinogenic hazard posed by exposure to 2,3,7,8-TCDD: an analysis using standard and internal measures of dose
Chemosphere
(1997) - et al.
2,3,7,8 Tetrachlorodibenzo-p-dioxin induction of cytochrome P4501A in cultured rat and human hepatocytes
Chem. Biol. Interact.
(2000) - et al.
Induction of CYP1A by benzo[k]fluoranthene in human hepatocytes: CYP1A1 or CYP1A2?
Arch. Biochem. Biophys.
(2001) - et al.
Quantitative liquid chromatography/mass spectrometry/mass spectrometry warfarin assay for in vitro cytochrome P450 studies
Anal. Biochem.
(2001) - et al.
Establishment of the transformants expressing human cytochrome P450 subtypes in HepG2, and their applications on drug metabolism and toxicology
Toxicol. In Vitro
(2001) - et al.
Structure and expression of the Ah receptor repressor gene. Identification of a novel mechanism of regulation of Ah (dioxin) receptor function
J. Biol. Chem.
(2001) - et al.
Superinduction of CYP1A1 transcription by cycloheximide. Role of the DNA binding site for the liganded Ah receptor
J. Biol. Chem.
(1992) - et al.
Superinduction of CYP1A1 gene expression. Regulation of 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced degradation of Ah receptor by cycloheximide
J. Biol. Chem.
(2000)
An IARC evaluation of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans as risk factors in human carcinogenesis
Environ. Health Perspect.
Human health effects after exposure to 2,3,7,8-TCDD
Food Addit. Contam.
Induction of cytochrome P4501A1 by 2,3,7,8-tetrachlorodibenzo-p-dioxin or indolo(3,2-b)carbazole is associated with oxidative DNA damage
Proc. Natl. Acad. Sci. USA
Human drug-metabolizing enzyme polymorphisms: effects on risk of toxicity and cancer
DNA Cell Biol.
Benzo[a]pyrene carcinogenicity is lost in mice lacking the aryl hydrocarbon receptor
Proc. Natl. Acad. Sci. USA
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2019, Toxicology LettersCitation Excerpt :The potential evil changes in TCDD-exposed mESCs were thus evaluated by analyzing transcriptional levels of CYP1A1 in different treatments, and the results confirmed significant up-regulation of CYP1A1 induced by TCDD stimulation in mESCs (Fig. 2A). As a marker of AhR receptor activation, CYP1A1 induction has been associated with carcinogenicity of TCDD (Zhang et al., 2006), the cellular tumor antigen, p53 mRNA levels remained unchanged in mESCs after chemical treatment though (Fig. 2B). The antagonist experiments based on both CH223191 and ANF revealed the significant decrease in CYP1A1 mRNA expressions of mESCs when compared with that in TCDD exposure group (Fig. S1), further confirming the crucial role of AhR signaling pathway in TCDD-induced effects.
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2017, Experimental Cell ResearchCitation Excerpt :Thus, the hepatocytes were treated with known activators of the transcription factors regulating the major CYP1-3 families. In accordance with previous studies, TCDD induced a large increase in CYP1A2 mRNA expression [5,27,28]. The increase was not affected by the presence of serum in the culturing media.
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Multidrug resistance protein (MRP) 4 attenuates benzo[a]pyrene-mediated DNA-adduct formation in human bronchoalveolar H358 cells
2012, Toxicology LettersCitation Excerpt :We have also shown in H358, human lung bronchoalveolar cells that CYP1A1/1B1 are responsible for the metabolism of benzo[a]pyrene (B[a]P), to the ultimate carcinogen (+)-B[a]PDE (Jiang et al., 2007). Detoxification of B[a]PDE occurs through glutathione (GSH) S-transferase (GST)-mediated adduct formation or further hydrolysis by epoxide hydrolase to the corresponding tetraols (Uno et al., 2004; Hukkanen et al., 2002; Zhang et al., 2006). B[a]PDE that escapes detoxification is able to enter to the nucleus and react with DNA to form adducts, particularly at the exocyclic amines of 2′-deoxyguanosine (dGuo) and 2′-deoxyadenosine (dAdo) (Fig. 1) (Ruan et al., 2007).
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Abbreviations: TCDD, 2,3,7,8-tetrachlorodibenzo-p-dioxin; Ah, aryl hydrocarbon; CYP, cytochrome P450; BaP, benzo(a)pyrene; ANM, anisomycin; CHX, cycloheximide; PBS, phosphate-buffered saline; LC/MS/MS, liquid chromatography–tandem mass spectrometry; α-NF, α-naphthoflavone; RT-PCR, reverse transcription-polymerase chain reaction; AhR, aryl hydrocarbon receptor; AhRR, aryl hydrocarbon receptor repressor; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; CT, calf thymus.