Accepted Manuscript The role of G protein-coupled receptors in lymphoid malignancies Adrienne Nugent, Richard L. Proia PII: S0898-6568(17)30218-8 DOI: doi: 10.1016/j.cellsig.2017.08.002 Reference: CLS 8973 To appear in: Cellular Signalling Received date: 25 May 2017 Revised date: 4 August 2017 Accepted date: 7 August 2017 Please cite this article as: Adrienne Nugent, Richard L. Proia , The role of G protein- coupled receptors in lymphoid malignancies, Cellular Signalling (2017), doi: 10.1016/ j.cellsig.2017.08.002 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. ACCEPTED MANUSCRIPT Title: The role of G protein-coupled receptors in lymphoid malignancies Adrienne Nugent and Richard L. Proia National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 10 Center Drive, Bethesda, MD, 20892, USA; [email protected] and [email protected] Address correspondence to: Richard L. Proia, PhD NIH/NIDDK 10 Center Drive, Bethesda, MD, 20892, USA (301) 496-4391 [email protected] Disclosure of conflicts of interest: None Author contributions: AN conceptualized, wrote and edited the review; RLP conceptualized and edited the review. All authors have approved the final article. ACCEPTED MANUSCRIPT ACCEPTED MANUSCRIPT ABSTRACT: B cell lymphoma consists of multiple individual diseases arising throughout the lifespan of B cell development. From pro-B cells in the bone marrow, through circulating mature memory B cells, each stage of B cell development is prone to oncogenic mutation and transformation, which can lead to a corresponding lymphoma. Therapies designed against individual types of lymphoma often target features that differ between malignant cells and the corresponding normal cells from which they arise. These genetic changes between tumor and normal cells can include oncogene activation, tumor suppressor gene repression and modified cell surface receptor expression. G protein-coupled receptors (GPCRs) are an important class of cell surface receptors that represent an ideal target for lymphoma therapeutics. GPCRs bind a wide range of ligands to relay extracellular signals through G protein-mediated signaling cascades. Each lymphoma subgroup expresses a unique pattern of GPCRs and efforts are underway to fully characterize these patterns at the genetic level. Aberrations such as overexpression, deletion and mutation of GPCRs have been characterized as having causative roles in lymphoma and such studies describing GPCRs in B cell lymphomas are summarized here. Keywords: GPCR; lymphoma; cancer; mutation; chemokine receptors; lipid receptors ACCEPTED MANUSCRIPT ACCEPTED MANUSCRIPT Abbreviations: ABC = Activated B cell-like ALL = Acute lymphoblastic leukemia ATP = Adenosine triphosphate B-ALL = B cell acute lymphoblastic leukemia BCR = B cell receptor BL = Burkitt lymphoma BLR1 = Burkitt lymphoma receptor 1 cAMP = Cyclic adenosine monophosphate CCND1 = Cyclin D1 CLL = Chronic lymphocytic leukemia CREB = Cyclic adenosine monophosphate response element-binding protein CRLF2 = Cytokine receptor like factor 2 DLBCL = Diffuse large B cell lymphoma DLBCL-NOS = Diffuse large B cell lymphoma-not otherwise specified EBI2 = Epstein-Barr virus-induced G protein-coupled receptor 2 FL = Follicular lymphoma GCB = Germinal center B cell-like GPCR = G protein-coupled receptor HCL = Hairy cell leukemia IGHV = Immunoglobulin heavy-chain variable region gene IgM = Immunoglobulin M IHC = Immunohistochemistry JNK = c-Jun N-terminal kinase LPA = Lysophosphatidic acid LPL = Lymphoplasmacytic lymphoma MALT = Mucosa-associated lymphoid tissue MAML2 = Mastermind like transcriptional coactivator 2 MAPK = Mitogen-activated protein kinase MCL = Mantle cell lymphoma MFI = Mean or median fluorescence intensity MGUS = Monoclonal gammopathy of undetermined significance MMP-9 = Matrix metallopeptidase 9 MZL = Marginal zone lymphoma NF-κB = Nuclear factor-kappa B NHL = Non-Hodgkin’s lymphoma PMBCL = Primary mediastinal large B-cell lymphoma S1P = SphingosineACCEPTED-1-phosphate MANUSCRIPT SLL = Small lymphocytic lymphoma T-ALL = T cell acute lymphoblastic leukemia TFH = Follicular helper T cell Treg = Regulatory T cell VEGF = Vascular endothelial growth factor VLA-4 = Very late antigen-4 WM = Waldenstrom macroglobulinemia ACCEPTED MANUSCRIPT 1. Introduction B cell lymphomas encompass a variety of neoplasms affecting lymphocytes in the immune system. In all cases, a normal B cell acquires a set of mutations or genetic aberrations that result in clonal proliferation of malignant cells. The stage of development a B cell is in when it acquires these genetic alterations dictates the subsequent lymphoma that develops. Through advances such as next generation sequencing and high throughput screening technologies, the underlying genetics and mechanisms of lymphomagenesis are becoming more clearly defined. GPCRs are seven-transmembrane domain cell surface-spanning receptors that regulate and transmit extracellular signals to induce numerous intracellular signaling pathways. There are hundreds of known GPCRs, each of which binds a specific ligand or set of ligands, which then induce conformational changes that lead to downstream signaling events. The cell surface ligand-binding capabilities of GPCRs make them highly desirable as drug targets for oncogenic cells. A complete and thorough understanding of GPCR expression in normal and malignant cells, coupled with a detailed knowledge of the molecules that bind to each GPCR and the downstream signaling pathways they activate, will reveal numerous opportunities for targeted therapeutics to improve disease outcome. A summary of what is known regarding GPCR expression and mutation in B cell lymphomas is reviewed here and outlined in Figure 1. 2. B-cell Acute Lymphoblastic Leukemia Acute lymphoblastic leukemia (ALL) is a neoplasm of the lymphoid precursor cells and is characterized as either B cell ALL (B-ALL) or T cell ALL (T-ALL) based on the cell of origin. B-ALL is the most common childhood malignancy and occurs less frequently in adults [1]. B-ALL cases are often subgrouped based on cell of origin, patient age, or the presence of a chromosomal aberration. Multiple chemokine receptors are expressed in B-ALL and these findings are summarized in Table 1. Chemokine receptor expression frequently varies between lineage-derived subgroups of B-ALL and this can provide insight into the underlying function of GPCRs in B-cell development and lymphomagenesis. For example, CXCR1 surface protein was not found in pro-B or pre-B ALL but was present in 5/17 (29%) cases of early pre-B and 3/5 (60%) cases of B-ALL [2]. Meanwhile, flow cytometry of CXCR2 and CXCR3 found these receptors to be expressed in all early pre-B, pre-B and B-ALL samples tested along with more than half of pro-B samples [2, 3]. However, another study that usedACCEPTED immunohistochemistry (IHC MANUSCRIPT) instead of flow cytometry to detect surface protein only found CXCR3 in 3/9 (33%) lymphoblastic leukemia/lymphoma patients [4]. CXCR4 is the most frequently studied chemokine receptor in lymphoma and its role in signaling in B-ALL has been extensively reviewed [5]. CXCR4 is normally expressed on pre-B and mature B cells and is essential for migration in lymphoma [4]. Elevated mRNA or protein expression of CXCR4 in B-ALL has been correlated with unfavorable clinical outcome [6], extramedullary organ invasiveness [7, 8], and time point and site of relapse [9]. CXCR4 has been identified in the majority of pro-B, pre-B and B-ALL cases and in ACCEPTED MANUSCRIPT some early pre-B cases [2, 3, 8, 10]. The estrogen receptor GPER1 (also known as GPR30) is also believed to regulate CXCR4 signaling in pre-B cell ALL [11]. CXCR5 is known to play a role in signaling and cell migration in lymphoma, however there are conflicting reports regarding its cell surface expression in B-ALL. Two flow cytometry studies did not identify any precursor-B, pro-B or pre-B patients with CXCR5 expressed [3, 10] while a third study found CXCR5+ cases in 3/9 (33%) pro-B, 5/17 (29%) early pre-B, 4/12 (33%) pre-B and 5/5 (100%) B-ALL cases [2]. A fourth report identified CXCR5 expression only on CD23+CD5+ B-ALL cells [12], while a final study found the receptor to be expressed in all B-ALL cases [4]. Other chemokine receptors that have been detected by flow cytometry in B-ALL include CCR3 and CCR4 [2, 12] as well as CXCR7 (also known as ACKR3), which is strongly upregulated in the bone marrow in B-ALL compared to normal tissue and plays a role in controlling CXCR4-mediated migration [13]. CCR7 cell surface expression has been found to vary between studies [2, 3, 12] while CCR1, CCR2, CCR5 and CCR6 were extremely rarely or never expressed [2, 3, 10, 14]. In addition to grouping cases of B-ALL by cell of origin, these lymphomas can also be subcharacterized by genetic rearrangements. Fusion of the purinergic receptor P2RY8 promoter to the CRLF2 (cytokine receptor like factor 2) gene frequently occurs in B-ALL but reports of the functional consequences of this rearrangement have been conflicting. Although P2RY8-CRLF2 fusions were significantly correlated with poor outcome in adolescent and adult patients [15, 16], the consequences of the fusion in pediatric B-ALL is less clear as some studies have found it to be associated with poor outcome [17-19] whereas others have not found any significant correlation [20, 21]. A meta-analysis of these studies concluded that presence of the P2RY8-CRLF2 fusion was in fact significantly associated with poor prognosis of relapse-free survival and event-free survival [22]. Another finding among these studies was that P2RY8-CRLF2 was more common in B-ALL patients with trisomy 21 [19, 23-26] or intrachromosomal amplification of chromosome 21 [27] than those with normal chromosome 21 [1, 18-21, 25, 26, 28-30].