Abstract 3843: TIMP1 and TIMP2 re-educate TGFβ induced pro-inflammatory/pro angiogenic decidual-like NK cells phenotype

Abstract Background: Tissue inhibitors of metalloproteases (TIMPs) have been reported to exert dual roles in cancer, based on the different cancer type and interactions with the tumor microenvironments. As inhibitors of Matrix metalloproteases (MMP) they downregulate invasion, metastasis and angiogenesis. However, TIMP1 levels have been found increased in patients with different types of cancer. Natural Killer cells have been found to be phenotypically and functionally compromised in several solid and hematological cancers. We were the first in characterizing NK pro-angiogenic phenotype in the peripheral blood and tumor tissues of patients with Non-small Cell Lung cancer, colorectal cancers, prostate of patients. Also, we found that pro-angiogenic NK cells in the peripheral blood of colorectal cancer patients release of TIMP-1 and TIMP-2, in a STAT3/STAT5-independent manner. Here, we investigated the effects of TIMP-1 and TIMP-2 recombinant proteins, using a TGFβ-mediated NK cell polarization model, in vitro. Methods: We investigated the effects of TIMP1 and TIMP2 recombinant proteins in hindering decidual-like markers in NK cells, generated by polarizing cytolytic NK cells with TGFβ. The effects of TIMP1 or TIMP2 on NK cell surface antigens were determined by multicolor flow cytometry. Results: We found that TIMP1 and TIMP2 were effective in interfering with TGFβ induced NK cell polarization towards a decidual-like-phenotype. TIMP1 and TIMP2 counteracted the effect of TGFβ in increasing the percentage of CD56bright, CD16-, CD9+ and CD49a+, and restoring normal levels for TIMP 1 and 2 also inhibited decrease levels of the activation marker NKG2D induced by TGFβ and decreased the TGFβ upregulated exhaustion marker TIM-3. NK cell degranulation capabilities against K562 cells were also decreased by TGFβ and not by TIMP1 or TIMP2. TIMP1 treatment could partially restore degranulation marker CD107a expression. Conclusions: Our results suggest a potential role of TIMPs in controlling the tumor-associated cytokine TGFβ-induced NK cell polarization. TGFβ stimulation represents a model to prove TIMP's new properties, further studies will help defining TIMPs immunomodulatory activities of NK cells in cancer, and their possible future diagnostic-therapeutic roles. Citation Format: Adriana Albini, Matteo Gallazzi, Maria Teresa Palano, Valentina Carlini, Luana Calabrone, Riccardo Ricotta, William G. Stetler-Stevenson, Douglas M. Noonan. TIMP1 and TIMP2 re-educate TGFβ induced pro-inflammatory/pro angiogenic decidual-like NK cells phenotype [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3843.