AB0174 EXPLORING A POTENTIAL ANTI-TUMOR IMMUNE MICROENVIRONMENT IN GIANT CELL ARTERITIS

Background The diagnosis of giant cell arteritis (GCA) is confirmed by temporal artery (TA) biopsy findings internal elastic lamina disruption, activated macrophages and T-lymphocytes infiltrating the arterial layers. immune microenvironment in GCA becomes T helper-1 polarized after steroid therapy consists potential anti-tumor cytokines including interferon-gamma (IFG) interleukin-12 (IL-12) which can be protective against development cancer. We have previously identified folate receptor beta positive GCA, serve as a target for hacking this microenvironment. Objectives To compare tumor outcomes our cohort vs controls who had TA biopsies. select line-up CD3, IFG, IL12 FRB proteins their expression GCA+ tissue that did not develop tumors versus -negative tissues developed tumors. assess persistence over time. Methods performed retrospective chart review subjects to long-term follow up. Formalin-fixed paraffin embedded sections were obtained from both groups immunohistochemical stains using antibodies. Results 40 demonstrated similar follow-up durations (76.9 70.1 years; NS), time-to-incident cancer (21 62 mos; NS) deaths (5% 17.5%;NS). older than (77.2 69.7 p= 0.004). Cancer incidence lower (25% vs.47.5%; p=0.036). incident cancers include 8 basal or squamous skin cancer(BCC/SCC) 1 each chronic lymphocytic leukemia, thyroid, esophageal angiosarcoma. 6 BCC/SCC, 2 breast, melanoma lymphoma, tonsil, parotid, colon, lung, renal, prostate, myelodysplastic syndrome metastatic disease unknown primary. Histopathology/IHC Findings: was selectively expressed correlated with CD3 expression. FRB, higher without compared cancer: (14 2.3;p=0.006), IFG (3 1;p=0.005), (1.5 0;p=0.003), (79 0;p=0.004). This multi- protein persisted years 3 repeat Conclusion has risk associated FRB+-macrophage Th1-polarized autoimmunity. References [1]Deng J, Younge BR, Olshen RA, et al. Th17 Th1 T-cell responses arteritis. Circulation . 2010;121:906-915. [2]Bruni D, Angell HK, Galon J. contexture immunoscore prognosis therapeutic efficacy. Nat Rev 2020;20:662-680. [3]Fridman WH, Pagès F, Sautès-Fridman C, human tumours: impact on clinical outcome. 2012;12:298-306. [4]Smyth MJ, Taniguchi M, Street SE activity IL-12: mechanisms innate immunity are model dose dependent. J Immunol 2000;165:2665-70. [5]Albano-Aluquin S, Malysz Aluquin VR, An analysis distribution arteritis: pilot study. Am Clin Exp 2017;6:107-114. [6]Xia W, Hilgenbrink Matteson L, A functional induced during macrophage activation used drugs macrophages. Blood 2009;113:438-446 Acknowledgements: NIL. Disclosure Interests None Declared.