PIAS1 regulates the expression of a panel of tumor suppressor genes.

<p>(<b>a</b>) Real-time quantitative PCR (Q-PCR) assay. MDA-MB231 cells containing control shRNA, PIAS1 shRNA1 or shRNA2 were cultured in DMEM plus 10% FBS (DMEM) or Stem Cell Media (SCM) for 30 h, and total RNA was used for Q-PCR assays with gene-specific primers. The gene names are labeled at the top left of each panel. The data were normalized by beta-Actin (<i>ACTB</i>) and presented as “Relative Expression” as compared to that in control shRNA cells under DMEM condition, which was set as “1” except for the <i>ESR1</i> gene (the expression was not detectable in control shRNA cells). Shown is a representative of 3 independent experiments. Error bars represent SD. ND, not detected. See also Table S1 and Table S2 in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0089464#pone.0089464.s001" target="_blank">File S1</a>. (<b>b</b>) Same as in <b>a</b> except that total RNA from fat pad tumor xenograft samples were used (n = 5). Error bars represent SEM. <i>P</i> values were determined by non-paired <i>t</i>-test.