ICOSLG and neoplasm: Huang et al. reported that TLR4 was expressed in murine tumor cells and that the activation of TLR4 in these cells by LPS induced the expression of various soluble factors including interleukin-6, inducible nitric oxide synthase, interleukin-12, B7-H1, and B7-H2 and rendered tumor cells resistant to CTL attack.