title: The impact of FANCD2 deficiency on formaldehyde-induced toxicity in human lymphoblastoid cell lines.
abstract: Formaldehyde (FA), a major industrial chemical and ubiquitous environmental pollutant, has recently been classified by the International Agency for Research on Cancer as a human leukemogen. The major mode of action of FA is thought to be the formation of DNA-protein cross-links (DPCs). Repair of DPCs may be mediated by the Fanconi anemia pathway; however, data supporting the involvement of this pathway are limited, particularly in human hematopoietic cells. Therefore, we assessed the role of FANCD2, a critical component of the Fanconi anemia pathway, in FA-induced toxicity in human lymphoblast cell models of FANCD2 deficiency (PD20 cells) and FANCD2 sufficiency (PD20-D2 cells). After treatment of the cells with 0-150 μM FA for 24 h, DPCs were increased in a dose-dependent manner in both cell lines, with greater increases in FANCD2-deficient PD20 cells. FA also induced cytotoxicity, micronuclei, chromosome aberrations, and apoptosis in a dose-dependent manner in both cell lines, with greater increases in cytotoxicity and apoptosis in PD20 cells. Increased levels of γ-ATR and γ-H2AX in both cell lines suggested the recognition of FA-induced DNA damage; however, the induction of BRCA2 was compromised in FANCD2-deficient PD20 cells, potentially reducing the capacity to repair DPCs. Together, these findings suggest that FANCD2 protein and the Fanconi anemia pathway are essential to protect human lymphoblastoid cells against FA toxicity. Future studies are needed to delineate the role of this pathway in mitigating FA-induced toxicity, particularly in hematopoietic stem cells, the target cells in leukemia.
authors.affiliation: Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, CA 94720-7356, USA.
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Ren
authors.forename: Zhiying
authors.initials: Z
authors.lastname: Ji
authors.forename: Cliona M
authors.initials: CM
authors.lastname: McHale
authors.forename: Jessica
authors.initials: J
authors.lastname: Yuh
authors.forename: Jessica
authors.initials: J
authors.lastname: Bersonda
authors.forename: Maycky
authors.initials: M
authors.lastname: Tang
authors.forename: Martyn T
authors.initials: MT
authors.lastname: Smith
authors.forename: Luoping
authors.initials: L
authors.lastname: Zhang
mesh_terms: D017209:Apoptosis / Q000187:drug effects / Q000235:genetics; D002460:Cell Line / Q000187:drug effects; D002869:Chromosome Aberrations; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005199:Fanconi Anemia / Q000235:genetics / Q000473:pathology; D052236:Fanconi Anemia Complementation Group D2 Protein / Q000235:genetics* / Q000378:metabolism; D005557:Formaldehyde / Q000009:adverse effects / Q000633:toxicity*; D006801:Humans; D015162:Micronucleus Tests; D011506:Proteins / Q000737:chemistry / Q000378:metabolism; D012130:Respiratory Hypersensitivity; D018675:Toxicity Tests / Q000379:methods
chemical_list: C499905:FANCD2 protein, human; D052236:Fanconi Anemia Complementation Group D2 Protein; D011506:Proteins; D005557:Formaldehyde; D004247:DNA