High ERp5/ADAM10 expression in lymph node microenvironment and impaired NKG2D ligands recognition in Hodgkin lymphomas

Abstract

Herein we describe that in classic Hodgkin lymphomas (cHL, n ‫؍‬ 25) the lymph node (LN) stroma displayed in situ high levels of transcription and expression of the disulfide-isomerase ERp5 and of the disintegrin-metalloproteinase ADAM10, able to shed the ligands for NKG2D (NKG2D-L) from the cell membrane. These enzymes were detected both in LN mesenchymal stromal cells ( IntroductionIt is now accepted that the so-called stress surveillance contributes to the anti-neoplastic immunity, both in solid tumors and hematologic malignancies, through the activation of the NKG2D receptor that recognizes NKG2D ligands (NKG2D-L) on cancer cells, including the MHC class-I related chain-A and -B (MIC-A/B) and the UL16-binding proteins 1-4 (ULBPs). [1][2][3][4][5] These ligands are commonly expressed at very low levels or retained in the cytoplasm, in healthy tissues, but their transcription and surface expression are enhanced on viral infection or tumor transformation. [5][6][7][8][9] Besides natural killer cells and CD8 ϩ T lymphocytes, ␥␦ T cells can recognize these molecules and activate an antitumor response in different cancers. [10][11][12][13][14][15][16][17] In this regard, we have described that ␥␦ T lymphocytes belonging to the V␦1 subset are expanded in patients with chronic lymphocytic leukemia (CLL) and nonHodgkin lymphomas (NHLs), where they proliferate in response to tumor cells, provided they express NKG2D-L, exert cytotoxicity, and produce anti-neoplastic or pro-differentiating cytokines, such as TNF-␣ and IL-4. 15,16 However, NKG2D-L can be shed by tumor cells and, in their soluble form, interact with NKG2D expressed by effector lymphocytes and hinder the recognition of tumor cells. 18,19 Proteolytic cleavage of MIC-A has been shown to depend on the thiol isomerase ERp5 and the disintegrins and metalloproteinases ADAM10 and ADAM17, which are also able to cleave ULBPs. 19,22 Overexpression of these enzymes has been reported in multiple myeloma and other tumors. [19][20][21][22][23] In turn, soluble (s) NKG2D-L and cytokines produced at the tumor site can down-regulate the expression of the NKG2D receptor on effector lymphocytes, contributing to tumor escape from immunosurveillance. [22][23][24][25] Indeed, the TGF-␤ has been shown to reduce the surface density of the NKG2D receptor on CD8 ϩ T and NK cells, impairing their antitumor reactivity in cancer patients. [24][25][26] Moreover, we and others reported that plasma levels of sNKG2D-L correlate with disease progression in multiple myeloma, CLL, NHL, and acute myeloid leukemias; in particular, among sNKG2D-L, both sMIC-A and sULBP2 have been shown as a prognostic marker for multiple myeloma and for the identification of early-stage CLL patients with risk of disease progression. [14][15][16]21,27,28 In this paper, we studied 25 classic HL (cHL) and found that the tumor microenvironment is prone to inhibit the development of an antitumor response. This is mainly because of the release of soluble MIC-A and ULBP3 by lymph node mesenchymal stromal cells (LN MS...

Genotoxic Stress Induces Senescence-Associated ADAM10-Dependent Release of NKG2D MIC Ligands in Multiple Myeloma Cells

“…Previous studies showed that ADAM10 is required for normal PC function (43), and its expression increases during B cell differentiation, reaching higher levels at the PC stage (44). However, no evidence is available for the malignant cell counterpart, although a role for ADAM10 in hematologic malignancies was recently reported (45,46). Importantly, we provide evidence that ADAM10 expression is enhanced in MM cell lines and in primary PCs in response to genotoxic agents, and its upregulation requires ROS generation and is associated with the acquisition of a senescent phenotype.…”

Aminobisphosphonates prevent the inhibitory effects exerted by lymph node stromal cells on anti-tumor V 2 T lymphocytes in non-Hodgkin lymphomas

“…LNMSC were isolated and cultured as described (Online Supplementary Appendix). 30,31 Co-cultures of LNMSC and Vd2T lymphocytes, or LNMSC and autologous LN cell suspensions were perfomed at the ratio of 1:10.…”

“…Immunofluorescence was performed as described. 31 Samples were run on CyAnADP flowcytometer (Beckman Coulter). Results are expressed as log mean fluorescence intensity (MFI) or percentage of positive cells.…”

“…RNA extraction and cDNA synthesis were performed as described. 31 Q-RT-PCR for TGFβ, IL4, IL12, IL15, IL10, TNFα, IFNg, GATA3, TXB21, STAT1, STAT5, STAT6 was performed on the 7900HT FastRT-PCR system (Applied Biosystems) with fluorescent Taqman method. mRNAs were normalized to RPLP0, referred to a standard curve and results were expressed as ΔC T. 34,35 Statistical analysis was performed using a two-tailed Student's t-test.…”

“…12,[28][29][30] In particular, we have recently described that gdT cells from the lymph nodes (LN) of HL patients co-cultured in vitro with autologous lymph-node derived mesenchymal stromal cells (LNMSC) strongly reduced their cytolytic activity against NKG2D-L + HL target cells. 31 Here, LNMSC from NHL lymph nodes have been derived to study their impact on effector functions and differentiation of Vd2 anti-tumor T lymphocytes. Furthermore, we have analyzed whether N-BPs can affect the LNMSC-mediated influence on Vd2 T cells.…”