TLR4 Thr399Ile Research Articles

Association of TLR4 polymorphisms (Asp299Gly and Thr399Ile) with sepsis: a meta-analysis and trial sequence analysis.

Several investigations have been carried out to explore the genetic association of TLR4 codon variants, specifically Asp299Gly and Thr399Ile, and susceptibility to sepsis, but the results have been contradictory. The present study aimed to conduct a meta-analysis to draw a definitive conclusion regarding the role of TLR4 genetic variants (Asp299Gly and Thr399Ile) in sepsis. A thorough literature search was conducted using the PubMed, Scopus, and Science Direct databases. The inclusion and exclusion criteria were established to ensure the accuracy of the data. The Comprehensive Meta-Analysis Software v4 was utilized to perform the meta-analysis and related analyses. A total of 13 studies were analyzed, including 2328 sepsis cases and 2495 healthy controls for the TLR4 Asp299Gly variant. Eight studies provided genotype data for the rs4986791 polymorphism. The Asp299Gly variant showed a marginal protective effect in the allele (p = 0.08, odds ratio = 0.71) and dominant (p = 0.09, odds ratio = 0.71) genetic models, although it was not statistically significant. The trial sequential analysis indicated that further case-control studies are necessary to draw definitive conclusions about the TLR4 polymorphisms in sepsis. The TLR4 Asp299Gly variant may have a protective effect against sepsis. However, additional research with larger sample sizes across diverse populations is required to validate this finding.

Association of Toll-like receptor-4 polymorphism with SARS CoV-2 infection in Kurdish Population

Genetic variations are critical for understanding clinical outcomes of infections including server acute respiratory syndrome coronavirus 2 (SARS CoV-2). The immunological reactions of human immune genes with SARS CoV-2 have been under investigation. Toll-like receptors (TLRs), a group of proteins, are important for microbial detections including bacteria and viruses. TLR4 can sense both bacterial lipopolysaccharides (LPS) and endogenous oxidized phospholipids triggered by Covid-19 infection. Two TLR4 single nucleotide polymorphisms (SNPs), Asp299Gly and Thr399Ile have been linked to infectious diseases. No studies have focused on these SNPs in association with Covid-19. This study aims to reveal the association between Covid-19 infection with these SNPs by comparing a group of patients and a general population. Restriction fragment length polymorphisms (RFLP) were used to identify the TLR4 SNPs in both the general population (n = 114) and Covid-19 patient groups (n = 125). The results found no association between the TLR4 polymorphisms and Covid-19 infections as the data showed no statistically significant difference between the compared groups. This suggested that these TLR4 SNPs may not be associated with Covid-19 infections.

The role of TLR-2 and TLR-4 gene polymorphisms in the development of sepsis in children with severe burns

Recently, many studies are based on the study of innate immunity genes, namely the role of TLRs in the development of various diseases. Severe burn injury is characterized by the development of hyperimmune reactions, which further leads to the development of multiple organ complications and sepsis. The aim of our study was to identify the frequency and prognostic value of polymorphism of TLR-2 Arg753Gln and TLR-4 Thr399 Ile genes and their role in the development of sepsis and MOD in children with severe burns. Materials and methods: genetic analysis of TLR-2 Arg 753 Gln and TLR-4 Thr399 Ile gene polymorphisms was performed in children with severe and extremely severe burns (n ​​= 22) who were treated in the anesthesiology department with intensive care beds. Results: as a result of the obtained data, the heterozygous genotype TLR-2 Arg 753 Gln was detected in 69.5% (n = 16), in 31.8% (n = 7) patients with burn injury polymorphism was not detected. In 13.6% (n = 3) cases, polymorphism was associated with sepsis and MOD. Sepsis and normal homozygous genotype were diagnosed in 4.5% (n = 1). Heterozygous genotype TLR-4 Thr399 Ile was observed in 18.2% (n = 4) patients, of which only 4.5% (n = 1) patients had polymorphism associated with sepsis and MOD. Analysis of the association of TLR 2 genotypes and markers of acute inflammation revealed statistically significant differences between the heterozygous TLR 2 Arg 753 Gln genotype and C-reactive protein (CRP) levels in the blood of patients on day 3 of burn disease. Conclusions: The study of the role of innate immune system genes is promising in predicting the development of sepsis and complications in severe burns and requires further careful study.

Systematic review and meta-analysis of human Toll-like receptors genetic polymorphisms for susceptibility to tuberculosis infection.

Epidemiological data from the world health organization (WHO) show that Globally an estimated 10 million (range, 8.9-11.0 million) people around the world were infected with TB in 2019. M.tuberculosis (M.tb) is the major cause of tuberculosis. Infection with M.tb has varied host immune responses because of the host genetic factor and its response to the infection. Genetic polymorphism in TLRs imparts susceptibility or resistance to the host against several diseases. In the present study, a systematic review and meta-analysis were performed to describe the relationship among various TLRs and SNPs involved in M.tb infection and their association with susceptibility to pulmonary tuberculosis in various populations of the world. PubMed and Scihub databases from 2008 to 2019 were searched and 58 articles were shortlisted for the present study to explore the association between TLRs gene polymorphisms and susceptibility to tuberculosis infection. The combined analysis showed that the polymorphisms TLR1 (rs5743618), TLR1 (rs4833095), TLR2 (-196 to -174) del, TLR2 (rs3804099), TLR4 (rs4986790), TLR4 (rs4986791), TLR4 (rs7873784), TLR6 (rs5743810), TLR8 (rs3764880), TLR9 (rs5743836), TLR9 (rs352139) were significantly associated with TB disease in certain ethnic population. In our meta-analysis study, we have also found variations between studies in some polymorphism, for example. The TLR1 (rs 5743618), TLR2 (rs5743708), TLR4 Asp299Gly, TLR4 Thr399Ile, TLR4 (rs7873784), TLR6 (rs5743810), TLR9 (rs5743836) was associated with the protection against TB. Meta-analysis was performed between polymorphisms and pulmonary tuberculosis to define increase or decrease in susceptibility to tuberculosis in various populations, which indicated that a relationship exists between SNPs/host genetic factors and susceptibility or resistance in patients suffering from pulmonary tuberculosis our finding concludes that this gene polymorphism may be associated with susceptibility to TB. The present study adds value to the various researches and studies going on various populations of the world in better understanding the role of TLR polymorphism in TB.

Clinical Implication of Toll-Like Receptors (TLR2 and TLR4) Polymorphisms in Adult Patients with Acute B-cell Lymphoblastic Leukemia.

Backgrounds:Neutropenia after intensive chemotherapy of acute lymphoblastic leukemia (ALL) could lead to infectious complications that affect outcome of acute leukemia patients. Many single-nucleotide polymorphisms (SNPs) of Toll-like receptors (TLRs) can affect the genetic susceptibility to infections. We investigated the impact of different SNPs on the incidence of developing sepsis and pneumonia in patients with newly diagnosed B-ALL following induction chemotherapy. Subjects and methods:We analyzed three SNPs in the TLR2 (Arg753Gln) and TLR4 (Asp299Gly& Thr399Ile) genes using polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) in a case control study of 40 precursor B-ALL patients and 50 control subjects. The risk of developing sepsis and pneumonia were assessed by multiple logistic regression analyses. Results:The presence of the TLR-2 AG polymorphism was significantly associated with pneumonia in B-ALL patients. Furthermore, TLR4 Thr399Ile AG was a risk factor for sepsis in B-ALL patients. Moreover; Significant association between TLR-2 AA, TLR-4 CC and TL-4 AA genotypes and longer OS were detected in studied B-ALL patients. Conclusion:We concluded that TLR-4 (AG and CT) genotypes are associated with high susceptibility to sepsis and pneumonia respectively; while, TLR-2, TLR-4 AA and TLR-4 CC genotypes could predict good B-ALL patients outcome.

Genotype Frequency of the Common TLR4 SNPs in a Kurdish Population: Global Reviews and Out-of-African Migrations.

Toll-like receptors (TLRs) are cellular innate immune receptors that explore microbial molecules. For instance, TLR4 can sense bacterial lipopolysaccharides, inducing cytokines and antimicrobial peptides against the bacteria. Single-nucleotide polymorphisms (SNPs) in TLR4 are associated with diseases such as septic shock. Therefore, investigations of common SNPs may help explain the pathogenesis of diseases and various innate immune responses to infections. This study investigated genotypic frequencies of the two common TLR4 SNPs, Asp299Gly and Thr399Ile, in a Kurdish population using restriction length fragment polymorphisms (RFLPs). Global frequencies of both TLR4 SNPs in different populations of sub-Saharan Africa, North Africa, western Asia, Eurasia, and East Asia were also used to infer human migrations and past settlements. The RFLP data demonstrate that, in the Kurdish population, the genotypic frequencies of both SNPs are similar to Iranian or other West Asian populations, which in turn are comparable to Eurasian populations, suggesting past admixture due to migrations, population intermixing, and common ancestry. Globally, the frequencies of the homozygous wild-types of TLR4 variants are prevalent, but homozygous mutants are rare or lacking in almost all global populations. Frequencies of the heterozygotes varied among populations. For instance, in sub-Saharan Africa the frequency of the Asp299Gly SNP is higher than that of Thr399Ile, whereas in the Arabian Peninsula both SNPs are present at high frequencies. In contrast, East Asian populations lack or have very low frequencies of both TLR4 SNPs of interest. Moreover, co-segregation of the TLR4 SNPs is common in some populations, which may indicate important associations with certain diseases. Future studies are required to link the TLR4 SNPs with either resistance or susceptibility to diseases.

Toll-Like Receptor 4 Polymorphisms (896A/G and 1196C/T) as an Indicator of COVID-19 Severity in a Convenience Sample of Egyptian Patients.

BackgroundThe clinical spectrum of COVID-19 is extremely variable. Thus, it is likely that the heterogeneity in the genetic make-up of the host may contribute to disease severity. Toll‐like receptor (TLR)-4 plays a vital role in the innate immune response to SARS-CoV-2 infection. The susceptibility of humans to severe COVID-19 concerning TLR-4 single nucleotide polymorphisms (SNPs) has not been well examined.ObjectiveThe goal of this research was to investigate the association between TLR-4 (Asp299Gly and Thr399Ile) SNPs and COVID-19 severity and progression as well as the cytokine storm in Egyptian patients.MethodsWe genotyped 300 adult COVID-19 Egyptian patients for TLR-4 (Asp299Gly and Thr399Ile) SNPs using PCR-restriction fragment length polymorphism (PCR-RFLP). We also measured interleukin (IL)-6 levels by enzyme-linked immunosorbent assay (ELISA) as an indicator of the cytokine storm.ResultsThe minor 299Gly (G) and 399Ile (T) alleles were associated with a significant (P < 0.001) positive risk of severe COVID-19 (OR = 3.14; 95% CI = 2.02–4.88 and OR = 2.75; 95% CI = 1.66–4.57), their frequency in the severe group were 71.8% (84/150) and 70.7% (58/150), respectively. We detected significant differences between TLR-4 (Asp299Gly, Thr399Ile) genotypes with regard to serum levels of IL-6. Levels of IL-6 increased significantly with the presence of the mutant 299Gly (G) and 399Ile (T) alleles to reach the highest levels in the Gly299Gly (GG) and the Ile399Ile (TT) genotypes (170 pg/mL (145–208.25) and 112 pg/mL (24–284.75), respectively).ConclusionThe TLR-4 (Asp299Gly and Thr399Ile) minor alleles 299Gly (G) and 399Ile (T) are associated with COVID-19 severity, mortality, and the cytokine storm.

Role of genetic variants of Vitamin D receptor, Toll-like receptor 2 and Toll-like receptor 4 in extrapulmonary tuberculosis

BackgroundTuberculosis (TB) is a chronic infectious disease caused by Mycobacterium tuberculosis (MTB). Vitamin D deficiency and vitamin D receptor (VDR) gene abnormalities confer susceptibility to tuberculosis. Toll-like receptors (TLRs), such as TLR-2, are also important mediators of inflammatory response against Mycobacterium tuberculosis. We evaluated VDR, TLR-2 and TLR-4 gene polymorphisms in patients with extrapulmonary tuberculosis (EPTB). ObjectivesTo find out a possible association of Vitamin D receptor (VDR) (rs731236), TLR-2 (196–174 Ins > Del) and TLR-4 (Thr399Ile) gene polymorphisms with extrapulmonary tuberculosis in ethnic Kashmiri population. MethodsA total of 100 extrapulmunary tuberculosis cases and 102 healthy controls were analyzed for Vitamin D receptor (VDR) (rs731236), TLR-2 (196–174 ins > del) and TLR-4 (Thr399Ile) gene polymorphisms using PCR-RFLP and Allele-Specific PCR methods. ResultsWe found increased frequency of TLR-4 Thr/Ile heterozygous genotype in cases as compared with healthy controls (22% vs 5.8%). Thus acting as a risk factor for extrapulmonary tuberculosis, as was elucidated from statistical analysis [OR, 4.5; 95% CI (1.74–11.68); P < 0.001]. In case of TLR-2 (196–174 ins > del) we observed significant differences in the homozygous variant (Del/Del) genotype of cases and controls (28% in cases & 2.94% in controls). Thus, TLR-2 (Del/Del) genotype acts as a strong risk factor for extrapulmonary tuberculosis predisposition [OR, 12.2; 95% CI (3.5–42.69); P < 0.001]. We did not find any significant differences in the genotypic distribution of (VDR) (rs731236) T > C SNP between cases and controls (P > 0.05). ConclusionTLR-4 (Thr/Ile) and TLR-2 (Del/Del) act as significant risk factors for extrapulmonary tuberculosis predisposition in ethnic Kashmiri population.

TLR4 and TLR9 polymorphism: Probable role in susceptibility among the population of Bihar for Indian visceral leishmaniasis.

Genetic variations in the host TLRs genes play an important role in susceptibility and/or resistance to visceral leishmaniasis by altering the host-pathogen interaction. In this study, we investigated the association between polymorphisms of TLR4 (Asp299Gly, Thr399Ile) and TLR-9 (T-1237C), with susceptibility to visceral leishmaniasis. A bi-directional PCR amplification of specific alleles technique was used to characterize the distribution of TLR4 (Asp299Gly and Thr399Ile) and TLR9 (T-1237C) polymorphisms. A total of 60 samples were randomly selected from confirmed visceral leishmaniasis patients and 24 endemic healthy volunteers. The samples were genotyped and allele frequencies were determined. We observed that TLR4 Asp299Gly and Thr399Ile genotypes were more frequent in visceral leishmaniasis patients (10% and 15% respectively) compared to controls (4.2% and 8.3% respectively). However, the differences were not significant in TLR4 Asp299Gly and Thr399Ile alleles and genotypes. In the case of TLR9, we observed the frequency of T1237C genotype was higher in visceral leishmaniasis patients (43.3%) than in healthy controls (33.3%). Statistically significant differences were observed in TLR9 T1237C alleles and genotypes. We concluded that TLR9 T1237C, but not TLR4, gene polymorphisms can be regarded as contributors to visceral leishmaniasis susceptibility among the Indian population of Bihar state.

TLR4 and TLR9 polymorphisms are not associated with either rheumatoid arthritis or systemic lupus erythematosus in Mexican patients

Toll-like receptor (TLR)-mediated signaling pathways induce a proinflammatory microenvironment to eradicate pathogens. However, in rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), TLRs can promote chronic inflammation. It has been shown that some TLR4 and TLR9 single nucleotide polymorphisms (SNPs) are risk factors for RA and SLE, but these findings have not been replicated in all populations; thus, results are inconclusive. We evaluated the TLR4 Asp299Gly, Thr399Ile, - 1892G/A SNPs, and the TLR9 Pro545Pro SNP to assess potential associations with RA and SLE in Mexican patients. This study included 474 patients with RA, 283 patients with SLE, and 424 healthy controls. We used a 5' nuclease allelic discrimination assay to genotype individuals for the four TLR4 and TLR9 polymorphisms. We found that the genotype or allelic frequencies of the TLR4 Asp299Gly, Thr399Ile, - 1892G/A, and TLR9 Pro545Pro polymorphisms were similar between patients and controls. We found no association under different genetic models. A haplotype analysis of TLR4 showed no association with either RA or SLE. We found no significant differences in the allelic or genotypic frequencies of TLR4 Asp299Gly, Thr399IIe, - 1892G/A, or TLR9 Pro545Pro between patients and controls. These findings suggested that these variants are not risk factors for RA or SLE in Mexican patients.

Clinical Implication of Toll-Like Receptors (TLR2 and TLR4) in Acute Myeloid Leukemia Patients.

Backgrounds:Toll-like receptors 2; 4 (TLR2;4) are an essential component of the innate immunity and play an important role in immune-surveillance and immune response to various microorganisms. This study aimed to investigate the association between TLR2 and TLR4 polymorphism and the risk of acquiring severe infections, and impact on AML patient’s outcome. Subjects and methods:Using polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP); we analyzed three SNPs in the TLR2 (Arg753Gln) and TLR4 (Asp299Gly and Thr399Ile) in 120 AML patients and 100 healthy control subjects. Results:No significant differences in genotype or alleles frequency between healthy controls and AML patients regarding TLR2 Arg753Gln, TLR4 Asp299Gly and TLR4 Thr399Ile polymorphisms (P>0.05 for all). Neutropenic fever was detected in 110 out of 120 (91.7%) of the studied AML patients. The sepsis and pneumonia were identified in 20 out of 120 patients (16.7%). The incidence of sepsis was associated with TLR2 Arg753Gln: AG genotypes, A allele and TLR4 Asp299Gly: CT genotype and C allele as compared to other genotypes and alleles. Moreover; TLR2 (Arg753Gln) GG polymorphisms significantly associated with shortest overall survival (OS) and shortest disease-free survival (DFS); while TLR4 polymorphisms affect the DSF only but not OS. In AML patients TLR2 Arg753Gln gene polymorphism is associated with high susceptibility to sepsis and TLR4 (Asp299Gly and Thr399Ile) gene polymorphism is associated with high susceptibility for both pneumonia; and sepsis. Conclusion: TLR2 Arg753Gln (AG; GG genotype) polymorphisms are associated with shortest OS and DFS. Moreover; significant association between TLR2 polymorphisms, TLR4 Arg753Gln polymorphisms and risk of severe infections in AML patients was documented.

Genetic Polymorphism of Toll-Like Receptor 4 Thr399Ile Variant in Iraqi Kurdish Population: Sulaymaniyah Province

Toll-like receptors (TLRs), encoded by innate immune genes, functions to detect microbial ligands. Studies found that polymorphisms in TLR genes among populations are associated with diseases. Among the classes of TLRs, TLR-4 is important for exploring bacterial lipopolysaccharide. TLR-4 Thre399Ile is one of the most important non-synonymous variant which varies among different background populations. Kurds, an ethnic population descended mainly from indigenous inhabitants of Zagros mountain survived for millennia, with nearly 40 million populations, are distributed in Iraq, Turkey, Iran and Syria. There are no studies on genetic variations of TLR4 in this population, particularly in Iraqi Kurdistan. The aim of this study is to find the percentage frequency of TLR4 Thr399Ile variant in Kurdish populations in Iraq, particularly in Sulaymaniyah province. The percentage of single nucleotide polymorphisms (SNPs) of the TLR4 gene was determined by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). The results showed that the heterozygous variant of TLR4 Thr399Ile is 7.1% (n=85) in Sulaymaniyah populations. However, no homozygous mutant variant was found; this suggests that it is either absent or seldom among Kurds in the region. This study emphasises the perceptiveness of the TLR SNP in Sulaymaniyah populations that recommends future study for linking this genetic variation with both infectious and immunological diseases, in addition to historical, anthropological and archaeological studies.

The role of TNF-α and TLR4 polymorphisms in the placenta of pregnant women complicated by preeclampsia and in silico analysis

Evidence showed that, pro inflammatory cytokines and mediators of innate immune responses may involve in the pathogenesis of preeclampsia (PE). Therefore, the present investigation aimed to examine the possible effects of placental TNF-α and TLR4 polymorphisms on PE susceptibility. MethodsThe placental tissues were collected after delivery from 111 PE and 115 healthy pregnant women. The TNF-α-308G/A (rs1800629), TNF-α-238G/A (rs361525), TLR4 Asp299Gly (rs4986790) and TLR4 Thr399Ile (rs4986791) polymorphisms were genotyped using PCR-RFLP method. Moreover, in-silico analysis was performed to evaluate the potential functions of these polymorphisms. ResultsThe TNF-α −308 GA genotype was associated with a decreased PE risk. The frequency of TNF-α −238G/A genotypes did not differ between two groups, however, the frequency of TNF-α −238A allele was significantly higher in controls. No relationship between TLR4 Thr399Ile and Asp299Gly polymorphisms and PE was found. In-silico analysis predicted that −308G to A substitution in the TNF-α promoter might lead to different allelic expressions. In addition, TLR4 Asp299Gly polymorphism would result in a major change in the mRNA and protein functions. ConclusionOur study for the first time presented evidence on the association of the placental TNF-α −308GA genotype and TNF-α −238A allele with decreased risk of PE in an Iranian population.

The Role of TLR4 Asp299Gly and TLR4 Thr399Ile Polymorphisms in the Pathogenesis of Urinary Tract Infections: First Evaluation in Infants and Children of Greek Origin.

Urinary tract infections are one of the most common and serious bacterial infections in a pediatric population. So far, they have mainly been related to age, gender, ethnicity, socioeconomic level, and the presence of underlying anatomical or functional, congenital, or acquired abnormalities. Recently, both innate and adaptive immunities and their interaction in the pathogenesis and the development of UTIs have been studied. The aim of this study was to assess the role and the effect of the two most frequent polymorphisms of TLR4 Asp299Gly and Thr399Ile on the development of UTIs in infants and children of Greek origin. We studied 51 infants and children with at least one episode of acute urinary tract infection and 109 healthy infants and children. We found that 27.5% of patients and 8.26% of healthy children carried the heterozygote genotype for TLR4 Asp299Gly. TLR4 Thr399Ile polymorphism was found to be higher in healthy children and lower in the patient group. No homozygosity for both studied polymorphisms was detected in our patients. In the group of healthy children, a homozygote genotype for TLR4 Asp299Gly (G/G) as well as for TLR4 Thr399Ile (T/T) was showed (1.84% and 0.92 respectively). These results indicate the role of TLR4 polymorphism as a genetic risk for the development of UTIs in infants and children of Greek origin.

Toll-like receptor-4 299Gly allele is associated with Guillain-Barré syndrome in Bangladesh.

ObjectiveTLR4 plays an important role in the pathogenesis of Guillain‐Barré syndrome (GBS). The relationships between TLR4 polymorphisms and susceptibility to GBS are poorly understood. We investigated the frequency and assessed the association of two single nucleotide polymorphisms (SNPs) in the extracellular domain of TLR4 (Asp299Gly and Thr399Ile) with disease susceptibility and the clinical features of GBS in a Bangladeshi cohort.MethodsA total of 290 subjects were included in this study: 141 patients with GBS and 149 unrelated healthy controls. The TLR4 polymorphisms Asp299Gly and Thr399Ile were genotyped using polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) assay.ResultsThe minor 299Gly allele was significantly associated with GBS susceptibility (P = 0.0137, OR = 1.97, 95% CI = 1.17–3.31), and was present at a significantly higher frequency in patients with the acute motor axonal neuropathy (AMAN) subtype of GBS (P = 0.0120, OR = 2.37, 95% CI = 1.26–4.47) than acute inflammatory demyelinating polyneuropathy (AIDP) subtype (P = 0.961, OR = 1.15, 95% CI = 0.38–3.48); when compared to healthy controls. The genotype frequency of the Asp299Gly polymorphism was not significantly different between patients with GBS and healthy controls. The Asp299‐Thr399 haplotype was associated with a significantly lower risk of developing GBS (P = 0.0451, OR = 0.63, 95% CI = 0.40–0.99). No association was observed between the Thr399Ile polymorphism and GBS disease susceptibility.InterpretationThe TLR4 minor 299Gly allele was associated with increased susceptibility to GBS and the axonal GBS subtype in the Bangladeshi population. However, no associations were observed between the genotypes of the Asp299Gly and Thr399Ile SNPs and antecedent C. jejuni infection or disease severity in Bangladeshi patients with GBS.

Absence of association between TLR4 Thr399Ile polymorphism and cervical cancer susceptibility

BackgroundToll-like receptors (TLRs) play a key role in pathogen detection and initiating inflammatory response. Several lines of evidence have suggested chronic inflammation as one of the major factors linked to carcinogenesis. Single nucleotide polymorphisms (SNPs) in TLR genes including TLR4 have been shown to be associated with cancer susceptibility, although reports have been conflicting. AimThe present case-control study was designed to ascertain the association of TLR4 C1196T/ Thr399Ile polymorphism with cervical cancer risk among Indian women. Patients and methodsThe study comprised of tumor biopsies from 110 histopathologically diagnosed cervical cancer cases and cervical smears from 141 disease free healthy controls. DNA was obtained using standard proteinase-K digestion and phenol-chloroform extraction method. Genotyping of samples was carried out by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) method. ResultsThe results showed presence of single genotype CC (Thr/Thr) and complete absence of T allele across all the sample types thereby showing genotypic frequency of 1.0, 0.0 and 0.0 for CC, CT and TT respectively in the study population. Patients aged >45 years showed association with late stages of cervical cancer. ConclusionComplete absence of T allele in our study subjects demonstrate no involvement of TLR4 Thr399Ile polymorphism in cervical cancer susceptibility. However, an association between increased age and late clinical staging was observed. A comprehensive analysis on a larger sample size covering diverse ethnic populations of India is warranted to comprehend the role of TLR4 Thr399Ile polymorphism.

Evaluation of the detection of Toll-like receptors (TLRs) in cancer development and progression in patients with colorectal cancer.

BackgroundToll-like receptors (TLRs) play essential role in innate and acquired immunity, are expressed in various cell types, and are associated with altered susceptibility to many diseases, and cancers. The aim of this study was to investigate TLR2 (-196 to-174del), TLR4 (Asp299Gly and Thr399Ile) and TLR9 (T1237C and T1486C) gene polymorphisms at risk of colorectal cancer (CRC) development and progression.MethodsPeripheral blood was obtained from 397 patients with adjuvant (stage II/III, n = 202) and metastatic (n = 195) CRC. Moreover, blood samples from 50 healthy volunteers and 40 patients with adenomatous polyps were also included as control groups. DNA from patients and controls was analyzed using PCR and PCR-RFLP for genotyping functional polymorphism within TLR2, TLR4 and TLR9 genotypes.ResultsTLR2–196 to-174del/del genotype was detected in 76.6% of the patients and was significantly higher that the controls groups (p<0.001). TLR4 Asp299Gly, TLR4 Thr399Ile, TLR9 T1237C and T1486C homozygous genotypes were detected in 70.5%, 70.5%, 61.5% and 61.5% of the patients respectively, and were also significantly higher than that in the control groups (p<0.001). All polymorphisms detected were also significantly associated with the metastatic disease (p<0.001) leading to shorter overall survival (p<0.001); whereas, TLR4 Asp299Gly and Thr399Ile polymorphisms were significantly associated with KRAS mutations.ConclusionsThe detection of higher frequencies of the TLR2, TLR4 and/or TLR9 polymorphisms in CRC patients compared with the control groups highlight the role of these polymorphism in CRC development and cancer progression.

The potential role of toll-like receptor 4 Asp299Gly polymorphism and its association with recurrent cystic echinococcosis in postoperative patients.

The study of pathogenesis mechanisms of larval stages in the Taeniidae has recently focused on host genetic factors, particularly toll-like receptor (TLR) variations. However, the potential role of TLR4 polymorphism in hydatidosis has not yet been sufficiently elucidated in postoperative patients. In this case-control investigation, 80 patients from Iran, including 40 with acute hydatidosis (AH) and 40 with recurrent hydatidosis (RH), and 80 ethnically matched controls were evaluated from February 2015 to February 2017. Hydatidosis patients were confirmed using radiological, immunological, and histopathological examinations. Genotyping of Asp299Gly and Thr399Ile of TLR4 single-nucleotide polymorphisms was determined by restriction fragment length polymorphism, sequencing, and phylogenetic strategies. The heterozygous mutant-type TLR4 Asp299Gly genotype indicated a tendency to be associated with the occurrence of RH (P = 0.060) and conferred a 3-fold risk for susceptibility. There was no difference in genotype frequency of Asp299Gly between patients with AH and healthy controls (P = 0.42; OR, 1.82; 95% CI, 0.11-30.1%). Interestingly, a frequency of the G allele (12%: Gly) was observed to be a risk factor for susceptibility to RH patients (P = 0.050; OR, 7.08; 95% CI, 0.97-51.5%). A relative genetic variability of TLR4 Asp299Gly was found in RH patients (haplotype diversity: 0.700) compared to AH patients and healthy controls (Hd: 0.000). The Asp299Gly genotype was dominantly identified in patients with hepatic hydatid cysts. The TLR4 Thr399Ile codon was not detected except in a patient with a pulmonary hydatid cyst. The current findings enhance our knowledge regarding the TLR4 Asp299Gly polymorphism potentially leading to the development of RH, by skewing the immune system towards a Th2 response. Identification of the Asp299Gly codon may be a diagnostic hallmark in RH patients who have undergone unsuccessful postoperative intervention. However, further studies with a higher case number are needed on ethnic population from various geographic regions, in order to confirm this hypothesis.

Association between Asp299Gly and Thr399Ile Polymorphisms in Toll-Like Receptor 4 Gene and Type 2 Diabetes Mellitus: Case-Control Study and Meta- Analysis

Objective: This paper describes a case-control study and a meta-analysis conducted to determine whether the TLR4 Asp299Gly (rs4986790) and Thr399Ile (rs4986791) polymorphisms are associated with type 2 diabetes mellitus (T2DM). Methods: In the case-control study were enrolled 1683 T2DM patients and 584 nondiabetic subjects from Brazil. A literature search was conducted in order to identify studies that investigated associations between the referred TLR4 polymorphisms and T2DM. Pooled odds ratios (OR) were calculated for allele contrast and dominant inheritance models. Results: In the case-control study, genotype and allele frequencies of the Asp299Gly and Thr399Ile polymorphisms differed between T2DM patients and nondiabetic subjects (P<0.05). Moreover, the presence of the minor alleles of these polymorphisms were significantly associated with protection for T2DM, after adjusting for ethnicity, under a dominant model [Asp299Gly: OR=0.68 (95% CI 0.49-0.94); Thr399Ile: OR=0.65 (95% CI 0.46-0.90)]. Seven studies were eligible for inclusion in the meta-analysis. Meta-analysis results showed that the Asp299Gly polymorphism was associated with T2DM protection [OR=0.68 (95% CI 0.46-1.00), allele contrast model]. Stratification by ethnicity revealed that both polymorphisms were associated with T2DM protection under allele contrast and dominant models in Brazilian population but not in Europeans. Conclusions: In our case-control study, we were able to demonstrate a possible association between the TLR4 Asp299Gly and Thr399Ile polymorphisms and protection for T2DM. In agreement, the meta-analysis results showed an association of the Asp299Gly polymorphism with T2DM protection in the whole group, and associations of the Asp299Gly and Thr399Ile polymorphisms with T2DM protection in the Brazilian group but not in European descendent. This is the largest TLR4 meta-analysis performed so far. In other ethnicities further studies with large sample size are necessary to confirm these associations in different ethnicities as well as to elucidate the roles possibly played by these polymorphisms in the pathogenesis of T2DM.

Prognostic Value of Genetic Markers for Efficacy Estimation of Induction Treatment Including Autologous Hematopoietic Stem Cell Transplantation in Multiple Myeloma Patients

Aim. To determine the value of polymorphisms of the immune response genes for the treatment efficacy in MM patients receiving high-dose chemotherapy and autologous hematopoietic stem cell transplantation (autoHSCT). Methods. The overall of 20 ММ patients (8 men and 12 women) were included in the study. The median age was 51.5 years (range 32-67). Clinical laboratory tests had been performed before melphalan high-dose (200 mg/m&lt;sup&gt;2&lt;/sup&gt;) conditioning therapy. In accordance with the achieved anticancer response to induction treatment the patients were divided into 3 groups: patients with partial remission (group 1; n = 7); patients with very good partial remission (group 2; n = 9); patients with complete remission (group 3; n = 4). Genotyping of 20 polymorphic loci of 14 immune response genes was performed using PCR. Results. The study showed that group 2 had no AA mutant homozygotes of IL10 in the G-1082A polymorphic locus compared to group 3 and no TT mutant homozygotes of TLR6 (Ser249Pro) compared to group 1. The patients with more pronounced mucositis (grade 2/3) compared to patients with minor mucositis (grade 0/1) had no CC mutant homozygotes of IL1ß in the G-1473C position and a smaller number of (CT+TT) heterozygous and homozygous haplotype carriers of IL10 with the T mutant allele in the C-819T mutation point. The multivariate analysis showed that the genetic marker statistically effecting the progression-free survival rates in MM patients after high-dose chemotherapy and autoHSCT was the polymorphous status of the IL10 (G-1082A), TNF (G-308A), TLR4 (Thr399Ile), and TLR9 in the T-1237C and A2848 polymorphic loci. Progression-free survival rates correlated with the mutation status of IL1ß (T-511C), IL2 (T-330G), IL6 (C-174G), CD14 (C-159T), TLR3 (Phe421Leu), and TLR4 (Asp299Gly). Conclusion. The obtained data show the correlation of 14 polymorphisms of 10 immune response genes with the immediate results of the induction treatment, and also with the severity of mucositis during the early post-transplant period, as well as overall and progression-free survival rates in MM patients. Due to a small sample volume further studies will be planned with the aim to verify the identified trends. The suggested hypothesis for immune response gene polymorphism effecting a disease prognosis can substantially contribute to developing of individualized approach to MM treatment.