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Your Environment. Your Health.

Selected Publications

Stem Cell Toxicology Group

  1. Luz AL, Wu X, Tokar EJ. Toxicology of Inorganics, Chapter 1; in Fishbein, J. (Ed): Advances in Molecular Toxicology, 2018. Vol. 12, Elsevier. (In Press)
  2. Ngalame NNO, Luz A, Makia NL, and Tokar EJ. Arsenic Alters Exosome Quantity and Cargo to Mediate Stem Cell Recruitment into a Cancer Stem Cell-like Phenotype. Toxicological Sciences. 2018. (In Press) doi: 10.1093/toxsci/kfy176
  3. Luz AL, Tokar EJ. Pluripotent Stem Cells in Developmental Toxicity Testing: A Review of Methodological Advances. Toxicological Sciences. 2018. (In Press) doi: 10.1093/toxsci/kfy174 (In Press)
  4. Ren NSX, Ji M, Tokar EJ, Busch E, Xu X, Lewis D, Xu Q, Li X, Wu WKK, Fargo DC, Keku T, Sandler R, and Li X: Haploinsufficiency of SIRT1 enhances glutamine metabolism and promotes cancer development. Current Biol. 27(4): 483-494, 2017. [Abstract]
  5. Ganini D, Leinisch F, Kumar A, Jiang JJ, Tokar EJ, Malone CC, Petrovich RM, and Mason RP. Fluorescent proteins such as eGFP lead to catalytic oxidative stress in cells. Redox Biol. 12:462-468, 2017. [Abstract]
  6. Morgan DL, Dixon D, King DH, Travlos GS, Herbert RA, French JE, Tokar EJ, Waalkes MP, Jokinen M P. NTP Research Report on Absence of Formaldehyde-Induced Neoplasia in Trp53 Haploinsufficient Mice Exposed by Inhalation. NTP RR 3. Research Triangle Park, NC: National Toxicology Program. (3): 1-30, 2017. [Abstract]
  7. Tokar EJ, Waalkes MP. Cancer Induced by Exposure to Arsenicals in Animals, Chapter 19; In; States, J. C. (Ed): Arsenic: Exposure Sources, Health Risks and Mechanisms of Toxicity, John Wiley & Sons, Inc. pp. 441-452, 2016.
  8. Tokar EJ, Xu Y, Waalkes MP. Stem Cell Targeting and Alteration by Arsenic, Chapter 17; In; States, J. C. (Ed): Arsenic: Exposure Sources, Health Risks and Mechanisms of Toxicity, John Wiley & Sons, Inc., pp. 397-420, 2016.
  9. Bailey KA, Smith AH, Tokar EJ, Graziano JH, Kim KW, Navasumrit P, Ruchirawat M, Thiantanawat A, Suk WA, Fry RC. Mechanisms underlying disease risk associated with early-life arsenic exposure: current research trends and scientific gaps. Environmental Health Perspectives 124(2):170–175, 2016. [Abstract]
  10. Ngalame NNO, Makia NL, Waalkes MP, and Tokar EJ. Mitigation of arsenic-induced acquired cancer phenotype in prostate cancer stem cells by miR-143 restoration. Toxicology and applied pharmacology 312: 11-18, 2016. [Abstract]
  11. Tokar, EJ. MicroRNAs: Small molecules with big effects. Toxicology and applied pharmacology 312: 1–2, 2016 [Special Issue Guest Editorial].
  12. Kumar A, Ehrenshaft M, Tokar EJ, Mason RP, and Sinha BK. Nitric oxide inhibits Topoisomerase II activity and induces resistance to Topoisomerase II-poisons in human tumor cells. Biochimica et Biophysica Acta 1860(7): 1519-1527, 2016. [Abstract]
  13. Carlin DJ, Naujokas MF, Bradham K, Cowden J, Heacock M, Henry H, Lee J, Thomas DJ, Thompson C, Tokar FJ, Waalkes MP, Birnbaum LS, and Suk WA. Arsenic and Environmental Health: State of the Science and Future Research Opportunities. Environmental Health Perspectives 124(7): 890-899, 2016.
  14. Ngalame NO, Waalkes MP, Tokar EJ. Silencing KRAS Overexpression in Cadmium-Transformed Prostate Epithelial Cells Mitigates Malignant Phenotype. Chemical research in toxicology 29(9): 1458-1467, 2016. [Abstract]
  15. Pelch KE, Tokar EJ, Merrick BA, and Waalkes MP. Differential DNA methylation profile of key genes in malignant prostate epithelial cells transformed by inorganic arsenic or cadmium. Toxicology and applied pharmacology 286(3):159-167, 2015. [Abstract]
  16. Tokar EJ, Person RJ, Ngalame NN, Qu W, Waalkes, MP. Oxidative Stress and the Inorganic Carcinogens, Chapter 16; In Kehrer, Roberts, Klotz (Eds): Oxidative Stress in Applied Basic Research and Clinical Practice, Springer (Humana Press), pp. 323-334, 2015.
  17. Sharma NK, Kumar A, Kumari A, Tokar EJ, Waalkes MP, Bortner CD, Williams J, Mason RP, Sinha BK. Nitric Oxide Down-Regulates Topoisomerase I and Induces Camptothecin Resistance in Human Breast MCF-7 Tumor Cells. PloS one 10(11):- , 2015. [Abstract]
  18. Person RJ, Olive Ngalame NN, Makia NL, Bell MW, Waalkes MP, Tokar EJ. Chronic inorganic arsenic exposure in vitro induces a cancer cell phenotype in human peripheral lung epithelial cells.Toxicology and applied pharmacology  286(1):36-43, 2015. [Abstract]
  19. Xu Y, Tokar EJ, Waalkes MP. Arsenic-induced transformation of human breast epithelia is estrogen receptor-independent but involves aromatase activation. Arch Toxicol 88(2): 263-274, 2014. [Abstract]
  20. Ngalame NN, Tokar EJ, Person RJ, Xu Y, Waalkes MP. Aberrant microRNA expression likely controls RAS oncogene activation during malignant transformation of human prostate epithelial and stem cells by arsenic. Toxicol. Sci. 138(2): 268-277, 2014. [Abstract]
  21. Waalkes MP, Qu W, Tokar EJ, Kissling GE, Dixon D. Lung tumors in mice induced by "whole life" inorganic arsenic exposure at human relevant doses. Arch. Toxicol. 88(8): 1619-1629, 2014. [Abstract]
  22. Ngalame NN, Tokar EJ, Person RJ, Waalkes MP. Silencing KRAS overexpression in arsenic-transformed prostate epithelial and stem cells partially mitigates malignant phenotype. Toxicol. Sci. 142(2): 489-496, 2014 [Abstract]
  23. Tokar EJ, Kojima C, Waalkes MP. Methylarsonous acid causes oxidative DNA damage in cells independent of the ability to biomethylate inorganic arsenic. Archives of Toxicology, 88(2):249-261, 2014. [Abstract]
  24. Tokar EJ, Boyd W, Freedman JH, Waalkes MP. Toxic Effects of Metals, Chapter 23; In: Klaassen, C. D. (Ed): Casarett and Doull's Toxicology: The Basic Science of Poisons, 8th Edition, McGraw-Hill Medical, New York, 2013.
  25. Severson PL, Tokar EJ, Vrba L, Waalkes MP, Futscher BW. Coordinate H3K9 and DNA methylation silencing of ZNFs in toxicant-induced malignant transformation. Epigenetics 8(10): 1080-1088, 2013 [Abstract]
  26. Tokar EJ, Person RJ, Sun Y, Perantoni AO, Waalkes MP. Chronic exposure of renal stem cells to inorganic arsenic induces a cancer phenotype. Chemical research in toxicology, 26(1):96-105, 2013. [Abstract]
  27. Person RJ, Tokar EJ, Xu Y, Orihuela R, Ngalame NN, Waalkes MP. Chronic cadmium exposure in vitro induces cancer cell characteristics in human lung cells. Toxicology and Applied Pharmacology 273(2):281-8, 2013. [Abstract]
  28. Xu Y, Tokar EJ, Person RJ, Orihuela RG, Ngalame NN, Waalkes MP. Recruitment of normal stem cells to an oncogenic phenotype by noncontiguous carcinogen-transformed epithelia depends on the transforming carcinogen. Environmental health perspectives 121(8):944-950, 2013. [Abstract]
  29. Chatterjee S, Ganini D, Tokar EJ, Kumar A, Das S, Corbett J, Kadiiska M, Waalkes M, Diehl AM, Mason RP. Leptin is key to peroxynitrite-mediated oxidative stress and Kupffer cell activation in experimental non-alcoholic steatohepatitis. Journal of hepatology 2013 58(4):778-784. [Abstract]
  30. Severson PL, Tokar EJ, Vrba L, Waalkes MP, Futscher BW. Agglomerates of aberrant DNA methylation are associated with toxicant-induced malignant transformation. Epigenetics: official journal of the DNA Methylation Society 7(11):1238-1248, 2012. [Abstract]
  31. Xu Y, Tokar EJ, Sun Y, Waalkes MP. Arsenic-transformed malignant prostate epithelia can convert noncontiguous normal stem cells into an oncogenic phenotype. Environmental health perspectives. 120(6):865-71, 2012. [Abstract]
  32. Zhan, L, Zhang, H, Zhang, Q, Woods, CG, Chen Y, Xue P, Dong J, Tokar, EJ, Xu, y, Hou, Y, Fu, J, Yarborough, K, Wang, A, Qu, W, Waalkes, MP, Andersen, ME, Pi, J. Regulatory role of KEAP1 and NRF2 in PPARγ expression and chemoresistance in human non-small-cell lung carcinoma cells. Journal of free radicals in biology & medicine  53(4):758-68, 2012. [Abstract]
  33. Tokar EJ, Diwan BA, Thomas DJ, Waalkes MP. Tumors and proliferative lesions in adult offspring after maternal exposure to methylarsonous acid during gestation in CD1 mice. Archives of toxicology  86(6):975-82, 2012. [Abstract]
  34. Qu W, Tokar EJ, Kim AJ, Bell MW, Waalkes MP. Chronic cadmium exposure in vitro causes acquisition of multiple tumor cell characteristics in human pancreatic epithelial cells. Environmental health perspectives.  120(9):1265-71, 2012. [Abstract]
  35. Shimada H, Hashiguchi T, Yasutake A, Waalkes MP, Imamura Y. Sexual dimorphism of cadmium-induced toxicity in rats: involvement of sex hormones. Archives of toxicology 2012 86(9):1475-80. [Abstract]
  36. Sun Y, Tokar EJ, Waalkes MP. Overabundance of Putative Cancer Stem Cells in Human Skin Keratinocyte Cells Malignantly Transformed by Arsenic. Toxicological Sciences 125(1):20-29, 2012. [Abstract]
  37. Tokar, E.J., Benbrahim-Tallaa, L., and Waalkes, M. P.: Metal ions in human cancer development.  Met Ions Life Sci. 8: 375-401, 2011. [Abstract]
  38. Tokar, E. J., Qu, W., and Waalkes, M. P.: Arsenic, stem cells, and the developmental basis of adult cancer.  Toxicol Sci. 120 Suppl 1: S192-203, 2011. [Abstract]
  39. Tokar, E.J., Diwan, B.A., Ward, J.M., Delker, D.A., and Waalkes, M.P.: Carcinogenic effects of "whole-life" exposure to inorganic arsenic in CD1 mice.  Toxicol Sci. 119: 73-83, 2011. [Abstract]
  40. Zhao, R., Hou, Y., Xue, P., Woods, C.G., Fu, J., Feng, B., Guan, D., Sun, G., Chan, J. Y., Waalkes, M. P., Andersen, M. E., and Pi, J.: Long isoforms of NRF1 contribute to arsenic-induced antioxidant response in human keratinocytes. Environ Health Perspect. 119(1): 56-62, 2011. [Abstract]
  41. Tokar, E. J., Benbrahim-Tallaa, L., Ward, J.M., Lunn, R., Sams, R. L., 2nd, and Waalkes, M. P.: Cancer in experimental animals exposed to arsenic and arsenic compounds.  Crit Rev Toxicol. 40: 912-927, 2010. [Abstract]
  42. Tokar, E. J., Diwan, B. A., and Waalkes, M. P.: Early life inorganic lead exposure induces testicular teratoma and renal and urinary bladder preneoplasia in adult metallothionein-knockout mice but not in wild type mice.  Toxicology. 276: 5-10, 2010. [Abstract]
  43. Tokar, E. J., Diwan, B.A., and Waalkes, M.P.: Arsenic exposure in utero and nonepidermal proliferative response in adulthood in Tg.AC mice.  Int J Toxicol. 29: 291-296, 2010. [Abstract]
  44. Tokar, E. J., Qu, W., Liu, J., Liu, W., Webber, M. M., Phang, J., and Waalkes, M. P.: Arsenic-specific stem cell selection during malignant transformation.  J. Natl. Cancer Inst. 102: 638-649, 2010. [Abstract]
  45. Tokar, E. J., Diwan, B. A., and Waalkes, M. P.: Arsenic exposure transforms human epithelial stem/progenitor cells into a cancer stem-like phenotype.  Envron. Health Perspect. 118: 108-115, 2010. [Abstract]
  46. Benbrahim-Tallaa, L., Tokar, E. J., Diwan, B. A., Dill, A. L., Coppin, J. F., and Waalkes, M. P.: Cadmium malignantly transforms normal human breast epithelial cells into a basal-like phenotype. Envron. Health Perspect. 117: 1847-1852, 2009. [Abstract]
  47. Kojima, C., Ramirez, D. C., Tokar, E. J., Himeno, S., Drobná, Z., Stýblo, M., Mason, R. P., and Waalkes, M. P.: Requirement of arsenic biomethylation for oxidative DNA damage.  J. Natl. Cancer Inst. 101: 1670-1681, 2009. [Abstract]
  48. Sun, Y., Pi, J., Wang, X., Tokar, E. J., Liu, J., and Waalkes, M. P.: Aberrant cytokeratin expression during arsenic-induced acquired malignant phenotype in human HaCaT keratinocytes consistent with epidermal carcinogenesis.  Toxicology. 262: 162-170, 2009. [Abstract]
  49. Pi, J., Diwan, B. A., Sun, Y., Qu, W., He, Y., Styblo, M., Liu, J., and Waalkes, M. P.: Arsenic-induced malignant transformation of human keratinocytes: Involvement of Nrf2.  Free Rad. Biol. Med.  45: 651-658, 2008. [Abstract]
  50. Waalkes, M. P., Liu, J., Germolec, D. R., Trempus, C. S., Cannon, R. E., Tokar, E. J., Tennant, R. W., Ward, J. M., and Diwan, B. A.: Arsenic exposure in utero exacerbates skin cancer response in adulthood with contemporaneous distortion of tumor stem cell dynamics. Cancer Res. 68: 8278-8285, 2008. [Abstract]
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