C-Myb is involved in regulation of <i>vav</i>1 expression in lung cancer cells.

<p>(A) Endogenous expression of <i>c-myb</i> mRNA in Jurkat T cells, H441 (<i>vav</i>1-positive) and H460 (<i>vav</i>1-negative) lung cancer cell lines was detected by RT-PCR and western blotting. (B) Empty vector pGL3 or the Le2 wt reporter construct was transfected either alone or with a c-Myb-expressing plasmid into H460 lung cancer cells (as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029939#s2" target="_blank">Materials and Methods</a>). Luciferase activity was measured 24 hr after transfection (top panel). Luciferase activity is expressed as fold induction relative to basic pGL3 expression. Values are the mean of five independent experiments; significance was determined using the unpaired student T test. (***) indicates p<0.01. The bottom panel shows the level of <i>c-myb</i> and actin mRNA and protein expression in the transfected cells as determined by RT-PCR and Western blotting respectively. (C) H441 lung cancer cells were transfected with either scrambled DNA (-) or with siRNA against c-Myb. Seventy-two hours later, the mRNA levels of <i>c-myb</i>, <i>vav1</i> and <i>actin</i> were detected by RT-PCR.