A combination of functional polymorphisms in the CASP8, MMP1, IL10 and SEPS1 genes affects risk of non-small cell lung cancer
Introduction
Exposure to tobacco smoke as well as environmental and occupational factors is major cause of lung cancer [1]. Enhanced inflammation due to environmental and intrinsic factors is an important co-factor in promotion and progression of lung cancer. Major genes modulating the level of inflammation in chemical carcinogenesis include interleukins 1 (IL-1) and 6 (IL-6), tumor necrosis factor alpha (TNF-α), and the transcription factor nuclear factor kappa B (NF-κB). Cigarette smoke also induces an endoplasmic reticulum (ER) stress response in the lung [2]. Several genes including Selenoprotein S (SEPS1) have been implicated in regulation of the ER-stress response.
Studies suggest that inflammatory reactions in the lung could be affected by polymorphisms in the genes regulating these responses. For example, polymorphisms in the TNF-α (G−308A, G+488A) and NF-κB (Ins-94Del) genes have been shown to modulate risk of several cancers [3], [4], [5], [6]. We have recently demonstrated that regulatory polymorphisms in the IL1B gene were correlated with increased risk of NSCLC and higher expression of IL1B mRNA in the lung [7]. In vitro studies using human lung epithelial cells showed that the functional polymorphism in the IL1B gene promoter (IL1B-31 T/C) had increased expressional activity after exposure to the lung carcinogen benzo(a)pyrene [8]. Among others, SEPS1 has been identified as an ER protein participating in processing and removal of misfolded proteins from the ER to the cytosol where they are destroyed by the proteasome in an ubiquitin-dependent manner [9]. Recently, the SEPS1 G-105A promoter SNP was identified and shown to influence the efficiency of removal of the misfolded proteins from the ER, resulting in increased ER-stress and elevated circulatory levels of the pro-inflammatory cytokines, particularly IL1β [9]. An interaction between the SEPS1 -105 SNP and the IL1B promoter SNPs towards an increased risk of rheumatid arthritis has been suggested as evidence for epistasis between the IL1B and SEPS1 genes [10].
The cysteine-dependent aspartate-specific protease-8 (CASP-8) is involved in apoptotic signaling as well as inflammation [11]. Apoptotic signals can lead to activation and cleavage of pro-caspase 8 into active caspase 8, thereby inducing apoptosis [12]. Caspase-8 may also trigger inflammation [13]. A functional six nucleotide insertion–deletion polymorphism (-652 ins/del) in the CASP8 gene promoter was recently described and reported to be associated with susceptibility to multiple cancers [14]. Yet another caspase protein, Caspase-1 (CASP-1) may mediate cytokine production caused by tobacco smoke. CASP-1 enzyme is essential for the cleavage of pro-IL1β protein into its active and mature form [15]. A polymorphism in the CASP1 gene (G+5455A) may affect the enzymatic activity of the CASP1 enzyme towards pro-IL1β and hence formation of the active IL1β protein [16].
The inflammation-related molecules such as the matrix metalloproteinase 1 (MMP-1) are associated with degradation of the extracellular matrix (ECM), tissue remodeling and alteration of cellular signals in multiple cancer types [17]. MMP-1 may also be involved in the migration of immune cells from the bloodstream to sites of inflammation. A functional insertion/deletion polymorphism in the -1607 promoter region (-1607 2G/1G) of the MMP1 gene has been shown to affect expression levels of the gene [18].
Interleukin-10 (IL-10) is an important immune regulatory cytokine, mostly with anti-inflammatory functions [19], [20]. The implication of IL-10 in lung cancer has previously been studied, but its significance is still not clear [21], [22]. Three promoter SNPs at positions -1082, -819 and -592, forming a specific haplotype, have been associated with decreased expression of IL10 gene [23].
Studies indicate that Toll-like receptor 4 (TLR-4) signaling contributes to environmentally induced airway inflammation [24]. The A-2026G polymorphism in the regulatory region of the TLR4 gene has been shown to be functional and has been associated with several diseases [25], [26], [27]. Another gene involved in the TLR4 signaling is the CD14 which is a receptor for bacterial wall components such as LPS and is a susceptibility locus for asthma and may be a critical factor in lung inflammation as well [28]). The functional C-260T polymorphism in the CD14 gene has been shown to affect expression of the gene [29].
We hypothesized that functional polymorphisms that are individually associated with a weak to moderate risk of lung cancer, may have additive effects leading to a much higher lung cancer risk. We examined the association between NSCLC and 11 functionally verified polymorphisms in genes related to lung inflammation, cellular stress and apoptosis. Our results suggest that a significant increase in the risk of NSCLC may require a combination of at least three functional polymorphisms. Specifically, we found that a combination of functional polymorphisms in the CASP8, MMP1, IL10 and SEPS1 genes increased risk of NSCLC to more than four-fold. The odds ratios were tested and further confirmed using statistical tools False-Positive Report Probability (FPRP) and Bayesian False Discovery Probability (BFDP) tests [30], [31] developed to correct for multiple testing errors in association studies.
In view of the significance of the TP53 gene in lung carcinogenesis, we also examined the genotypes in relation to TP53 mutations in the lung tumors available from a subset of lung cancer patients.
Section snippets
Study population
The characteristics of lung cancer patients and healthy controls included in the present study are summarized in Table 1. The details of the study population are recently published by Landvik et al. [7]. Briefly, 455 lung cancer patients were admitted for surgery at the university hospitals in Oslo or Bergen between 1986 and 2001. Diagnosis of lung cancer was ascertained by reviewing histological slides from tumor tissue and 442 non-small cell lung cancer (NSCLC) cases were enrolled in the
Results
The characteristics of NSCLC patients and healthy controls are shown in Table 1. Eleven polymorphisms in nine genes (Table 2), involved in inflammation, cellular stress and apoptosis were analyzed for association with risk of NSCLC. The polymorphisms were selected on the basis of confirmed functionality [3], [9], [14], [16], [18], [23], [25], [29], [37], [38]. Genotypes were obtained for >92% of cases and controls for all eleven polymorphisms as shown in online supplementary Tables 1 and 2 (
Discussion
In this study we have examined the risk of NSCLC associated with eleven functional polymorphisms in nine genes. We investigated further the interaction between four of the polymorphisms in CASP8, MMP1, SEPS1 and IL10 genes. The results showed a step-wise increase in risk of NSCLC with increasing number of risk genotypes.
IL-10 is an important immunoregulatory cytokine with anti-inflammatory properties and capacity to inhibit pro-inflammatory cytokines including IL-1β, IL-6 and TNF-α [39] and is
Conflict of interest
The authors declare no conflicts of interest.
Acknowledgments
The authors gratefully acknowledge collaboration of Dr. Lodve Stangeland, Haukeland University Hospital, Bergen, and Dr. Anne Naalsund, National University Hospital, Oslo for recruiting the lung cancer patients. We are grateful to Ms. Elín Einarsdóttir Thornér, Ms. Tove Andreassen and Mr. Erik Eide for excellent technical assistance. The National Health Screening Service (Norway) is acknowledged for collecting and providing biological materials and demographic data for the controls.
Funding:
References (53)
- et al.
Frequent genotype changes at -308, and 488 regions of the tumor necrosis factor-alpha (TNF-alpha) gene in patients with prostate cancer
J Urol
(2000) - et al.
A functional insertion/deletion polymorphism in the promoter region of the NFKB1 gene increases susceptibility for prostate cancer
Cancer Genet Cytogenet
(2009) - et al.
Association of TNF-alpha polymorphism with susceptibility to and severity of non-small cell lung cancer
Lung Cancer
(2006) - et al.
Allele-specific induction of IL1B-31T/C promoter polymorphism by lung carcinogens
Mutat Res
(2008) - et al.
Non-apoptotic functions of caspase-8
Biochem Pharmacol
(2008) - et al.
The involvement of genetic polymorphism of IL-10 promoter in non-small cell lung cancer
Lung Cancer
(2005) A Bayesian measure of the probability of false discovery in genetic epidemiology studies
Am J Hum Genet
(2007)- et al.
Role of estrogen receptor in regulation of polycyclic aromatic hydrocarbon metabolic activation in lung
Lung Cancer
(2004) - et al.
The -308 tumor necrosis factor-alpha promoter polymorphism effects transcription
Mol Immunol
(1997) - et al.
IL-12 and IL-10 polymorphisms and their effects on cytokine production
Cytokine
(2005)
NF-kappaB1 (p50) homodimers differentially regulate pro- and anti-inflammatory cytokines in macrophages
J Biol Chem
Matrix metalloproteinase-1 expression induced by IL-1beta requires acid sphingomyelinase
FEBS Lett
The ER-overload response: activation of NF-kappa B
Trends Biochem Sci
Activation of the selenoprotein SEPS1 gene expression by pro-inflammatory cytokines in HepG2 cells
Cytokine
Oxidative stress and nuclear factor-kappaB activation: a reassessment of the evidence in the light of recent discoveries
Biochem Pharmacol
The molecular epidemiology of lung cancer
Carcinogenesis
Cigarette smoke induces endoplasmic reticulum stress and the unfolded protein response in normal and malignant human lung cells
BMC Cancer
Role of tumour necrosis factor gene polymorphisms (-308 and -238) in breast cancer susceptibility and severity
Breast Cancer Res
A specific interleukin-1B haplotype correlates with high levels of IL1B mRNA in the lung and increased risk of non-small cell lung cancer
Carcinogenesis
Genetic variation in selenoprotein S influences inflammatory response
Nat Genet
Evidence of epistasis between Interleukin-1 and Selenoprotein-S with susceptibility to RA
Ann Rheum Dis
Caspase mechanisms
Adv Exp Med Biol
Stimulation of Toll-like receptor 3 and 4 induces interleukin-1beta maturation by caspase-8
J Exp Med
A six-nucleotide insertion-deletion polymorphism in the CASP8 promoter is associated with susceptibility to multiple cancers
Nat Genet
Inflammatory caspases and inflammasomes: master switches of inflammation
Cell Death Differ
Inflammation and apoptosis genes and the risk of restenosis after percutaneous coronary intervention
Pharmacogenet Genom
Cited by (65)
Association of CASP8 polymorphisms and cancer susceptibility: A meta-analysis
2020, European Journal of PharmacologyCitation Excerpt :Among CASP8 polymorphisms, the CASP8 rs3834129 variant is of important interest due to its functional significance. Numerous studies have inspected the association between a functional six nucleotide deletion polymorphism (−652 6N del, rs3834129) in the promoter of CASP8 and the risk of developing different types of cancer (Arnaout et al., 2012; Bagherabad et al., 2019; Carvalho et al., 2015; Cavalcante et al., 2017; Chatterjee et al., 2011; Cybulski et al., 2008; de Martino et al., 2013; De Vecchi et al., 2009; Frank et al., 2008; Fu et al., 2011; Gangwar et al., 2009; George et al., 2012; Haiman et al., 2008b; Hart et al., 2011; Hashemi et al., 2012; Hosgood et al., 2008; Kesarwani et al., 2011; Lee et al., 2010; Li et al., 2010; Liamarkopoulos et al., 2011; Liu et al., 2017b; Ma et al., 2011; Malik et al., 2011; Marques et al., 2017; Ovsepyan et al., 2017; Pardini et al., 2014; Pittman et al., 2008; Shih et al., 2019; Son et al., 2006; Srivastava et al., 2010; Sun et al., 2007; Tang et al., 2015; Theodoropoulos et al., 2011; Tong et al., 2012; Umar et al., 2011; Wang et al., 2009; Wang et al., 2012; Wu et al., 2019; Wu et al., 2013; Xiao et al., 2013; Xiao et al., 2011; Yang et al., 2008; Zhu et al., 2010). In the current study, the analysis of the 83 case–control studies, including 48,546 cancer cases and 57,838 controls, indicated that the CASP8 rs3834129 polymorphism significantly reduced the risk of overall cancer.
Effect of IL2RA and IL2RB gene polymorphisms on lung cancer risk
2019, International ImmunopharmacologyCitation Excerpt :The results showed that rs791588 and rs12722498 of IL2RA had notable associations with a decreased risk of lung cancer. Smoking is a major environmental risk factor, which has been demonstrated to have a significant association with lung cancer risk [30–32]. Therefore, we estimated the relationship of IL2RA and IL2RB polymorphisms with susceptibility to lung cancer stratified by smoking status.
Selenoproteins and Metastasis
2017, Advances in Cancer ResearchCitation Excerpt :The ER selenoproteins involved in the unfolded protein response within this organelle include SELENOF, SELENOK, and SELENOS (Kelly, Greene, Carroll, McElvaney, & O'Neill, 2009; Labunskyy, Yoo, Hatfield, & Gladyshev, 2009; Lee et al., 2015). Polymorphisms in SELENOS have been linked to increased risk for different cancers (Hart et al., 2011; Shibata et al., 2009). SELENOF has been shown to have a protumorigenesis and metastasis role, although exactly how it promotes these activities is unclear (Irons et al., 2010; Tsuji et al., 2015).