CHARACTERIZATION OF THE EXPRESSION PATTERN OF LIGANDS OF THE ACTIVATING RECEPTOR NKG2D IN RENAL CELL CARCINOMA AND ANALYSIS OF NKG2D EXPRESSION IN NK CELLS AND CD8+ T CELLS

SOL YANEL NUÑEZ; FERNANDO PABLO SECIN; MERCEDES BEATRIZ FUERTES; FLORENCIA SECCHIARI; AGUSTÍN ROVEGNO; NICOLAS IGNACIO TORRES; NORBERTO WALTER ZWIRNER; ANDREA ZIBLAT; JESSICA MARIEL SIERRA; CAROLINA INES DOMAICA

Congreso; Reunión conjunta de sociedades Biomédicas-65 reunión anual de la SAI; 2017

Renal cell carcinoma (RCC) is an aggressive neoplasm with metastatic potential and is consider one of the most common types of cancer in older adults. Actually, nephrectomy constitutes the gold-standard treatment for localized RCC; however this type of cancer remains silent during early stages, becoming evident when metastasis may have already occurred, representing a therapeutic challenge. It is known that a diverse array of ligands of the NK cell activating receptor NKG2D (NKG2DLs) are expressed by different tumors; however the pattern and relevance of the expression of these molecules remains unknown in many cases. NKG2DLs comprise MICA, MICB and 6 members of the ULBP family. As these molecules may constitute attractive targets for immunotherapy and potential prognostic and therapeutic biomarkers, the aim of this study was to initiate the characterization of the expression pattern of these NKG2DLs in peripheral blood mononuclear cells (PBMCs), tumor infiltrating lymphocytes (TIL) and tumor cells from RCC patients as well as in PBMCs from healthy donors (HD); and to determine the amount of expression of NKG2D in NK cells and CD8+ T cells using multicolor flow cytometry. For RCC patients (n=6) large amount of expression of MICA, was observed in tumor cells, while in TIL, not only MICA, but also ULBP-3 and ULBP-4 were highly expressed. This expression pattern was not present neither in PBMCs from RCC patients, nor from HD (n=5), although NK cells and CD8+ T cells in RCC patients expressed lower levels of NKG2D compared to those observed in HD (p