Figure 3. CCAR2 deficiency promotes IL-8 production following H₂O₂ treatment.

Cells were transfected with siUniversal (siU) or siCCAR2 (siC-a or siC-b). (A) Forty-eight hours after transfection, HeLa cells were treated with 1 mM H₂O₂ for 2 h. Expression of CCAR2 and IL-8 mRNA was validated by semi-quantitative RT-PCR (right panel). The band of PCR product and background on agarose gel was inverted to black and white, respectively. The levels of each mRNA were normalized to that of β-actin and are shown in the bar graph (left panel). ^*P < 0.05 (CCAR2) and ^#P < 0.05 (IL-8), significantly different from control cells. (B, C) Twelve hours after treatment of HeLa or SiHa cells with 1 mM H₂O₂ for 2 h, culture supernatants containing extracellular IL-8 were collected for ELISA. Intracellular levels of CCAR2 protein were confirmed by Western blotting (right panel). Relative levels of secreted IL-8 protein are shown in the bar graph (left panel). ^*P < 0.05, significantly different from control cells.