LTB4R2 and breast carcinoma: Finally, MyD88 overexpression alone upregulated the levels of 5-LO and 12-LO, as well as the quantity of BLT2 ligands (Fig. 4E and F), indicating that the MyD88-5-LO/12-LO-LTB4/12(S)-HETE-linked pathway lies upstream of BLT2 in the LPS-potentiated invasiveness in breast cancer cells (as summarized in Fig. 6B).