Skip to main content
. 2011 Jan 6;103(4):317–333. doi: 10.1093/jnci/djq541

Figure 6.

Figure 6

Effect of ARRB1-specific siRNA on nicotine-induced overexpression of E2F-responsive genes and on antiapoptotic effects of nicotine. A) Effect of silencing of ARRB1 on BIRC5, CDC6, and CDC25A mRNA levels in response to nicotine treatment in A549-EV and A549-sh cells. Serum-starved A549-EV and A549-sh cells were treated with 1 μM nicotine for 24 hours. Subsequently, the levels of BIRC5, CDC6, and TYMS mRNA were analyzed by real-time polymerase chain reaction (PCR). The means and 95% confidence intervals from two independent experiments are presented ***P < .001. B) Effect of suppression of ARRB1 levels on serum-induced overexpression of BIRC5, CDC6, and CDC25A mRNA. Serum-starved A549-EV and A549-sh cells were incubated with medium containing 10% fetal bovine serum for 24 hours, and the levels of BIRC5, CDC6, and TYMS mRNA were analyzed by real-time PCR. C) Role of ARRB1 in antiapoptotic effects of nicotine. Serum-starved A549-EV and A549-sh cells were treated with 1 μM nicotine for 30 minutes, then 20 μM cisplatin was added, and the cells were incubated for 24 hours. Apoptosis was measured by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. The means and 95% confidence intervals from two independent experiments are shown ***P < .001. D) Effect of suppression of ARRB1 levels on the induction of XIAP and BIRC5 in response to nicotine. Serum-starved A549-EV and A549-sh cells were treated with 1 μM nicotine for 24, 48, or 72 hours. The expression levels of XIAP, BIRC5, and ARRB1 were analyzed by immunoblotting. ACTB was used as a loading control. All P values were calculated using a two-sided Student t test.