Different phenotype of peripheral blood and intratumoral NK cells and CD8+ T cells in renal cell carcinoma patients may underlay distinct functional abnormalities

NÚÑEZ, SOL YANEL; SECÍN, FERNANDO; DOMAICA, CAROLINA INÉS; SECCHIARI, FLORENCIA; ROVEGNO, AGUSTÍN; TORRES, NICOLÁS IGNACIO; ZWIRNER, NORBERTO WALTER; ZIBLAT, ANDREA; SIERRA, JESSICA MARIEL; FUERTES, MERCEDES BEATRIZ

Buenos Aires

Congreso; Reunión Conjunta de Sociedades de Biociencias y 64a Reunión Anual de la Sociedad Argentina de Inmunología; 2017

Sociedad Argentina de Inmunología

Renal cell carcinoma (RCC) is an aggressive neoplasm with metastatic potential and is considered one of the most common types of cancer in older adults. Partial or radical nephrectomy constitutes the gold-standard treatment for RCC. However this type of cancer remains silent during early stages, becoming evident when metastasis may have already occurred, representing a therapeutic challenge due to patient?s poor prognosis. Different tumors express a diverse array of ligands of the NK cell activating receptor NKG2D (NKG2DLs), but their expression pattern and relevance in RCC remains unknown. NKG2DLs comprise MICA, MICB and 6 members of the ULBP family (ULBP-1 to -6). As they may constitute attractive targets for immunotherapy and potential prognostic and therapeutic biomarkers, the aim of this study was: a) to characterize the expression pattern of these NKG2DLs and b) to analyze the expression of NKG2D on NK cells and CD8+ T cells in peripheral blood mononuclear cells (PBMC), tumor infiltrating lymphoid cells (TIL) and tumor cells from RCC patients as well as in PBMC from healthy donors (HD) using multicolor flow cytometry. In RCC patients (n=6), high expression of MICA was observed on tumor cells, while on TIL, not only MICA, but also ULBP-3 and ULBP-4 were highly expressed. Conversely, PBMC from RCC patients and HD (n=5) did not express NKG2DLs. Also, NK cells and CD8+ T cells in PBMC from RCC patients expressed decreased amounts of NKG2D compared to HD (p