581 Topical calcipotriol plus imiquimod immunotherapy for non-keratinocyte skin cancers

Non-keratinocyte cutaneous malignancies including breast cancer metastasis and melanoma in situ are often poor surgical candidates due to their anatomical location, size the morbidities associated with surgery. Imiquimod, a toll-like receptor 7 agonist, is used for treatment of these malignancies, which activates innate immunity skin. However, imiquimod’s modest effect on activation adaptive limits its efficacy as monotherapy. We have previously demonstrated that topical induction thymic stromal lymphopoietin (TSLP) cytokine by calcipotriol protects against skin development directly activating T cell immunity. Herein, we demonstrate combination TSLP inducer (i.e., retinoic acid) an immune agent imiquimod STING agonist) leads robust antitumor malignancies. Two applications plus reduced subcutaneous MMTV-PyMTtg tumor growth compared or alone (p = 0.011). This suppression was increased proliferation CD4+ CD8+ cells microenvironment. Following injection B16-F10 into flanks wild-type mice, acid Imiquimod blocked < 0.05). Interestingly, another activator, DMXAA (STING agonist), also effectively inhibited 0.019) induced infiltrating cells. These findings highlight synergic novel immunotherapy