The Genetic Polymorphisms of NLRP3 Inflammasome Associated with T Helper Cells in Patients with Multiple Myeloma

Hindawi Journal of Immunology Research Volume 2018, Article ID 7569809, 13 pages https://doi.org/10.1155/2018/7569809 Research Article The Genetic Polymorphisms of NLRP3 Inflammasome Associated with T Helper Cells in Patients with Multiple Myeloma Xueyun Zhao,1,2 Mingqiang Hua,1 Shuxin Yan,1 Jie Yu,1 Fengjiao Han,1 Chaoqin Zhong,1 Ruiqing Wang,1 Chen Zhang,1 Ming Hou,1 and Daoxin Ma 1 1 2 Department of Hematology, Qilu Hospital of Shandong University, Jinan, Shandong 250012, China Department of Hematology, Baotou Central Hospital, Baotou, Inner Mongolia Autonomous Region 014040, China Correspondence should be addressed to Daoxin Ma; Received 31 January 2018; Revised 28 June 2018; Accepted 17 July 2018; Published 23 August 2018 Academic Editor: Nejat K. Egilmez Copyright © 2018 Xueyun Zhao et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The pathogenesis of multiple myeloma (MM) remains unclear and the NLRP3 inflammasome has been more and more recognized in the progression of many diseases. To investigate the role of the NLRP3 inflammasome in MM, we determined the genetic polymorphisms and expression of NLRP3 inflammasome-related genes (IL-1β, IL-18, CARD8, and NF-κB) in MM patients, and explored their clinical relevance. Furthermore, we investigated the relationship of the NLRP3 inflammasome with Th cells in MM. Our study showed that the CARD8-C10X (rs2043211) AT genotype contributed to the susceptibility of MM. CARD8C10X TT patients had earlier clinical stage. The WBC count in the three CARD8 genotypes showed an increasing trend (AA<AT<TT). Compared with patients with NF-κB-94 ins/del ATTG ins/ins and ins/del, patients with del/del had the highest myeloma cell ratio. Patients with IL-18 (rs16944) TT had the highest hemoglobin concentration (GG<GT<TT). Furthermore, we found that the genotype of CARD8-C10X (rs2043211) or NF-κB-94 ins/del ATTG was closely related to the frequency of Th1. Therefore, the genetic polymorphisms of the NLRP3 inflammasome associated with Th cells might be involved in the pathogenesis of multiple myeloma. 1. Introduction Multiple myeloma (MM) is a life-threatening plasma cell malignancy, for which the pathogenesis is unclear and standard therapy is inadequate. Many genetic and immunological alterations are involved in the pathogenesis of MM. It is of vital importance to explore its immunological mechanism and find the therapeutic target for MM. Inflammasomes play key roles in the immune system, which can trigger innate immune defenses and promote adaptive immune responses [1]. Some studies have shown that inflammasomes are involved in the pathophysiology of MM [2]. The most well-known inflammasome is NLRP3. It is a protein complex, including NLRP3 (NLR family, pyrin domain-containing 3), the adaptor ASC (apoptosisassociated speck-like protein containing a C-terminal caspaserecruitment domain), and caspase-1, which is responsible for the maturation and secretion of proinflammatory cytokines, such as interleukin IL-1β and IL-18 [3]. Moreover, the caspase-recruitment domain-containing protein 8 (CARD8) controls the activity of caspase-1 and regulation of caspase1-mediated IL-1 and IL-18 activation [4]. NF-κB, another key molecule of inflammasome, is involved in the growth and survival of myeloma cells in the bone marrow microenvironment. IL-6 is also important for the growth and survival of myeloma cells, and it can stimulate osteoclastogenesis. The correlation between IL-6 and inflammasomes is rarely reported. One of the functions of the NLRP3 inflammasome is the regulation of Th1 and Th17 responses by affecting the secretion of its effector molecules that can markedly affect T cell-mediated autoimmunity [5]. In addition, a published report has shown that NLRP3 is expressed during the differentiation of CD4+ T cells and is specifically involved in the polarization of Th2 cells [6]. These in vitro and in vivo studies suggest that the NLRP3 inflammasome is closely related to T helper cells, and they interact with each other to participate 2 in the onset and progression of inflammatory, immune, or neoplastic diseases, such as pulmonary inflammation, multiple sclerosis, and lung cancer [5, 6]. The detailed relationship of the NLRP3 inflammasome and Th cells in MM has not been clarified until now. Genetic polymorphisms involved with the NLRP3 inflammasome were linked to various diseases, such as rheumatoid arthritis, ankylosing spondylitis, melanoma, liver cancer, lung cancer, and ovarian cancer [7–9]. Meanwhile, a truncating polymorphism (rs2043211) can produce a nonfunctional CARD8 and induce an amplification of the inflammatory process, or even evolve into cancer [4]. However, the function of the NLRP3 inflammasome in MM has not yet been clearly clarified. To illuminate the roles of the NLRP3 inflammasome in MM, we determined the polymorphism and expression of NLRP3 inflammasome-related genes in MM patients. Moreover, we investigated their relationship with Th cells and explored their effects in the pathogenesis of MM. 2. Materials and Methods 2.1. Patients and Controls. A total of 355 MM patients (138 females and 217 males) with a median age of 60 (25–89) years and 350 controls (148 females and 202 males) with a median age of 55 (26–90) years were included in the study for the detection of genetic polymorphisms (Table 1). 42 newly diagnosed MM patients were recruited for testing the genetic polymorphisms and the mRNA expressions of NLRP3 inflammasome-related genes and the plasma levels of effector molecules IL-1β, IL-18, and IL-6 in BM. Furthermore, 24 newly diagnosed MM patients were recruited for analyzing the genetic polymorphisms of NLRP3 inflammasome-related genes and the percentage of T helper cell subsets (Th1/Th2/ Th9/Th17/Th22/Treg) in peripheral blood. The patients were enrolled from Qilu Hospital, Shandong University between April 2007 and November 2017. The diagnosis of multiple myeloma was based on the International Myeloma Working Group criteria [10]. The Durie-Salmon (DS) clinical staging system and International Staging System (ISS) were used in staging the subjects with MM. This study was approved by the Medical Ethical Committee of Qilu Hospital, Shandong University, China. Informed consent was obtained from all patients before enrollment in the study in accordance with the Declaration of Helsinki. 2.2. DNA Extraction and Genotyping. DNA was extracted from bone marrow or peripheral blood samples of 355 MM patients and 350 controls following the manufacturer’s instruction of the TIANamp blood DNA kit (Tiangen Biotech, Beijing, China). The detection reagent of the three SNPs, IL-1β (rs16944), IL-18 (rs1946518), and CARD8-C10X (rs2043211), were purchased from Thermo Fisher Scientific (Cat. # 4351379). NF-κB-94 ins/del ATTG promoter polymorphism was detected using the forward primer: 5′-C (...truncated)