Figure 6.

TLR4 overexpressed CAL-27 cells grew faster and were more resistant to cetuximab in vivo and in vitro. (A) CAL-27 cells transfected with overexpression vectors of TLR4 or control vectors were injected into nude mice. Cetuximab was peritoneally injected 7 days later and tumor volume was measured every 3 days. (B) IHC analyses of iNOS expression in tumor tissues (200×). (C) The expression of TLR4, MyD88 and TRIF in xenograft was measured by RT-PCR. CAL-27 cells transfected with overexpression vectors of TLR4 (E) or control vectors (D) were injected into nude mice. Cetuximab combined with TAK242 was peritoneally injected 7 days later and tumor volume was measured every 3 days. (F) Xenograft resistant to cetuximab was implanted subcutaneously. Cetuximab and TAK242 were peritoneally injected 7 days later and tumor volume was measured every 3 days. Data were represented as mean ± SD of at least three independent experiments; *P<0.05, **P<0.01; ***P<0.001.