Arsenite and insulin exhibit opposing effects on epidermal growth factor receptor and keratinocyte proliferative potential

Patterson, TJ; Rice, RH

HERO ID

732047

Reference Type

Journal Article

Year

2007

Language

English

PMID

17400267

HERO ID 732047
In Press No
Year 2007
Title Arsenite and insulin exhibit opposing effects on epidermal growth factor receptor and keratinocyte proliferative potential
Authors Patterson, TJ; Rice, RH
Journal Toxicology and Applied Pharmacology
Volume 221
Issue 1
Page Numbers 119-128
Abstract Previous work has suggested that arsenic exposure contributes to skin carcinogenesis by preserving the proliferative potential of human epidermal keratinocytes, thereby slowing the exit of putative target stem cells into the differentiation pathway. To find a molecular basis for this action, present work has explored the influence of arsenite on keratinocyte responses to epidermal growth factor (EGF). The ability of cultured keratinocytes to found colonies upon passaging several days after confluence was preserved by arsenite and EGF in an additive fashion, but neither was effective when the receptor tyrosine kinase activity was inhibited. Arsenite prevented the loss of EGF receptor protein and phosphorylation of tyrosine 1173, preserving its capability to signal. The level of nuclear beta-catenin was higher in cells treated with arsenite and EGF in parallel to elevated colony forming ability, and expression of a dominant negative beta-catenin suppressed the increase in both colony forming ability and yield of putative stem cells induced by arsenite and EGF. As judged by expression of three genes regulated by beta-catenin, this transcription factor had substantially higher activity in the arsenite/EGF-treated cells. Trivalent antimony exhibited the same effects as arsenite. A novel finding is that insulin in the medium induced the loss of EGF receptor protein, which was largely prevented by arsenite exposure.
Doi 10.1016/j.taap.2007.02.003
Pmid 17400267
Wosid WOS:000246612000013
Is Certified Translation No
Dupe Override No
Comments |WOS:000246612000013
Is Public Yes
Language Text English
Keyword antimony; arsenite; beta-catenin; epidermal growth factor; insulin; keratinocyte
Is Qa No