Ras Oncogene-Mediated Progressive Silencing of Extracellular Superoxide Dismutase in Tumorigenesis

Figure 4

Effect of the histone deacetylation inhibitor trichostatin A (TSA) on SOD3 mRNA expression. (a–c) Human thyroid cells showed reduced SOD3 mRNA production in Nthy cells modeling normal thyroid cells and no alteration in papillary thyroid cancer TPC1 or anaplastic thyroid cancer 8505c cells. (d–f) The expression analysis from PC Cl3 cells supported the data obtained from the human cells; sod3 expression was significantly reduced in control PC Cl3 cells and not altered in E1A transfected cells. (g–j) TSA treatment led to decreased sod3 expression in FRLT5 cells modeling normal thyroid but did not affect expression in clone V13 or V21 stably transfected with the H-RasV12 oncogene. TSA treatment increased sod3 mRNA synthesis only in PC PTC1 and FRLT5 V39 cells. The data are expressed as the mean ± SD. The values are represented (, , and ).

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