Dados do Trabalho

Título

Tumor microenvironment of clear cell renal cell carcinoma modulate the NK cell phenotype

Introdução

The discovery and characterization of new biomarkers that can be utilized as response predictors to immunotherapy has attracted the attention in the last years. Important structures associated with antitumor response and clinical benefits after immunotherapy are the tertiary lymphoid structures, composed by a mantle of tumor-reactivity T cells and a core with B and follicular dendritic cells. Understanding this cell network can promote important answers about antitumor immune response.

Objetivo

In this context, we aim to characterize the immune cells composition in peritumoral and tumoral tissues, as well as peripheral blood of patients with clear cell renal cell carcinoma (ccRCC). In addition, we will evaluate the immune spatial organization in the tumoral tissue.

Métodos

The study was approved by the Institutional Research Ethics Committee (3223/22). We initially analyzed the immune composition in tumor and peritumor tissues and blood from treatment-naive patients with CCRcc that underwent nephrectomy at A.C.Camargo Cancer Center (n = 11) by multiparametric flow cytometry. We also analyzed the spatial organization of immune cells in tumor tissues by immunohistochemistry (IHC) with single-staining (ST) and double-staining (DS) in FFPE tissue slides from 13 patients. Sections were stained with anti-CD20 (B cell marker) and anti-CD23 (follicular dendritic cell marker), aiming to identify and classify the TLS and its maturation state. For DS, we used the anti-CD56 (NK cell marker) and plus anti-CAIX (Clear cell Carcinoma marker). All reactions were performed using the Ventana BenchMark XT system and the UltraView Universal DAB Detection Kit, following the manufacturer’s recommendations

Resultados

Previous analysis by our group, underscores the elevated abundance of NK cells in CCRcc compared with other tumor types. CCRcc showed an abundante NK cells, represented in some patients approximately 15% of all leukocytes in TT. Furthermore, NK cells present in the tumor have a distinct phenotype of those that are found in peripheral blood and peritumor tissue. Both in normal tissue and blood, the NKs are predominantly CD56dim/CD16+. These cells undergo phenotype changes in TT becoming CD56bright/CD16- with increased expression of homing and activation markers (CD103, CD69 and CD25), and decreased expression of the GZMB and CD16. Analysis of tumor samples by IHC, revealed that approximately 90% of the all patients had TLSs in different maturation stages determined by intensity of CD23 and presence of the germinal center. Interessantly, we detected a significantly higher density of NK cells within mature TLSs than immature or TT.

Conclusões

Our results elucidated a NK cells phenotype changes between compartments, indicating that the tumoral microenvironment produces signals that can induce changes in the functionality of these cells. Furthermore, in an unprecedented way we detected NK cells within TLS and show that this abundance is associated with the TLS maturation stage. In the next steps, we will try to determine the function of such cells in TLS organization, as well as, in the immune response against tumoral cells.

Palavras-chave

Natural Killer Cells, Clear Cell Renal Cell Carcinoma and Tumor microenvimonment.

Financiador do resumo

Bolsista de Doutorado FAPESP 2022/00747 e FAPESP 18/14034-8 (T.S.M).