Effects of EGFR inhibition on 7KCh-induced inflammation.

<p>ARPE19 cells were treated with 8 µM 7KCh for 24 hr and the mRNA inductions of the inflammatory markers were measured by qRT-PCR. <b>(a)</b> Measurements (mean ± s.d., <i>n</i> = 3) with and without 5 µM AG1478 (tyrosine kinase inhibitor specific to EGFR). AG1478 suppressed the mRNA induction of VEGF (4.6 to 2.7 fold), CHOP (23.7 to 11.3 fold), and GRP78 (6.2 to 3.3 fold) and a minor but statistically significant reduction in IL-6. It did not have a statistically significant increase on IL-1β and IL-8. <b>(b)</b> Measurements of secreted cytokine (mean ± s.d.) in conditioned medium after treatment with 6 µM 7KCh for 48 hr (VEGF, <i>n</i> = 3) or 8 µM 7KCh for 24 hr (IL-6 and IL-8, <i>n</i> = 4) with and without 5 µM AG1478. AG1478 treatment reduced the 7KCh-induced secretion of VEGF (1035 pg/ml to 638 pg/ml) but had no effect on IL-6 and 8. <b>(c)</b> Immunoblot measuring the expression of CHOP and GRP78 in response to AG1478. A slight reduction in CHOP expression was observed but no effect on GRP78. *<i>p</i><0.05, two-tailed Student's t-test.