Differential Cytotoxic Effects of Sodium Meta-arsenite on Human Cancer Cells, Dental Papilla Stem Cells and
Somatic Cells
Correlate with Telomeric
Properties and Gene Expression
BYEONG-GYUN JEON, B. MOHANA KUMAR, EUN-JU KANG, GEUN-HO MAENG, YEON-MI LEE, YOUNG-
SOOL HAH, SUN-A OCK, DAE-OH KWACK, BONG-
WOOK PARK and GYU-JIN RHO
Abstract
We investigated the effects of sodium metaarsenite (NaAsO2) on human cancer cells (MDA-MB-231,
MCF-7 and U-87 MG), dental papilla tissue stem cells (DPSCs) and somatic cells [MRC-5 fetal fibroblasts and
adult muscle cells (MCs)] by examining telomericproperties, endogenous reverse transcriptase (RT) activity and the
expression of tumorigenesis-linked genes. Half maximal inhibitory concentration (IC50) values were higher in DPSCs
and MCs, possessing longer telomere lengths when compared to cancer cells. Levels of telomerase and RT
activity, and the expression of protein 53 (p53), B-cell lymphoma 2 (BCL2), nuclear factor kappa-light-chainenhancer
of activated B-cells (NFκB), transforming growth factor beta (TGFβ) and vascular endothelial growth factor
(VEGF) were significantly lower in cancer cells following sodium metaarsenite treatment, whereas the effect was
absent or marginally detected in DPSCs and somatic cells. Collectively, sodium meta-arseniteeffectively induced
cellular cytotoxicityby inhibiting telomerase and RT activity, and down-regulating transcript levels in cancer cells with
shorter telomere lengths, whereas more tolerance was evident in DPSCs and somatic cells possessing longer
telomere lengths.