{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\n LTB₄R2, also known as BLT2, is a G protein–coupled receptor that, despite its lower affinity for leukotriene B₄ compared to BLT1, binds structurally related eicosanoids (notably 12‐hydroxyheptadecatrienoic acid) and is expressed more widely across tissues. Its activation elicits diverse biological responses that are highly context dependent. In immune and inflammatory settings, BLT2 mediates chemotactic responses and promotes the generation of reactive oxygen species (ROS) that trigger downstream signaling cascades (including NF‐κB and MAP kinases), thereby modulating cytokine expression and inflammatory cell recruitment. Such actions contribute to the pathogenesis of diseases such as rheumatoid arthritis, atherosclerosis, and allergic airway inflammation. In parallel, BLT2 signaling in epithelial cells reinforces barrier function—enhancing tight junction protein expression and improving resistance to injury in the gastrointestinal tract and skin—which helps limit inflammation. Moreover, aberrant BLT2 activation in cancer cells has been linked to enhanced survival, proliferation, invasiveness, and metastasis. In several malignancies including ovarian, breast, pancreatic, and bladder cancer, BLT2 stimulation triggers NADPH oxidase–dependent ROS generation and the activation of pro‐tumorigenic effectors such as STAT3 and matrix metalloproteinases. Collectively, these studies underscore the multifaceted roles of BLT2 in mediating both pro‐inflammatory and tissue‐protective processes, and they highlight its promise as a therapeutic target in inflammatory disorders and cancer progression"}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": ";"}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "3", "end_ref": "8"}]}, {"type": "t", "text": ";"}, {"type": "fg", "children": [{"type": "fg_f", "ref": "9"}]}, {"type": "t", "text": ";."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "11", "end_ref": "17"}]}, {"type": "t", "text": "\n "}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Andrew M Tager, Andrew D Luster "}, {"type": "b", "children": [{"type": "t", "text": "BLT1 and BLT2: the leukotriene B(4) receptors."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Prostaglandins Leukot Essent Fatty Acids (2003)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/s0952-3278(03)00073-5"}], "href": "https://doi.org/10.1016/s0952-3278(03"}, {"type": "t", "text": "00073-5) PMID: "}, {"type": "a", "children": [{"type": "t", "text": "12895595"}], "href": "https://pubmed.ncbi.nlm.nih.gov/12895595"}]}, {"type": "r", "ref": 2, "children": [{"type": "t", "text": "Toshiaki Okuno, Yoshiko Iizuka, Hiroshi Okazaki, et al. 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