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

Abstract

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 Prognostic Value of the Detection of Microbial Translocation in the Blood of Colorectal Cancer Patients

“…As described previously by our group and others, TLR and VDR polymorphisms have been significantly associated with cancer development, progression, and, therefore, patients' clinical outcome [18,19,49,50]. Linked to the fact that TLR and the VDR genes play an important role in the prevention and elimination of infections, their mutations result in the impaired activation of these receptors, decreased response to microbial particles, and impaired homeostasis, thus leading to carcinogenesis and disease progression [51][52][53][54][55][56].…”

“…TLR2 (−196 to −174 bp), TLR4 (Asp299Gly and Thr399Ile), and TLR9 (T1237C and T1486C) polymorphisms and TaqI, ApaI, FokI, and BsmI polymorphisms of the VDR gene have been described previously [18,19], and their correlation with the presence of microbial DNA in the blood of CRC patients was investigated ( Table 3). A significant coexistence was observed between the detection of all four different microbial DNA fragments with all different VDR and TLR polymorphisms.…”

“…The present single-institution study was a retrospective study, aiming to investigate the detection of microbial DNA fragments in the blood of CRC patients before their treatment initiation. Progression-free survival (PFS) and overall survival (OS) were calculated, as previously described [18], and all experiments were performed blindly to the clinical data. Statistical analysis was performed using the SPSS v. 20 software (IBM Corp. Armonk, NY, USA), based on contingency tables, including hazard ratios (HR) and 95% CI calculations, as previously described [18].…”

“…Progression-free survival (PFS) and overall survival (OS) were calculated, as previously described [18], and all experiments were performed blindly to the clinical data. Statistical analysis was performed using the SPSS v. 20 software (IBM Corp. Armonk, NY, USA), based on contingency tables, including hazard ratios (HR) and 95% CI calculations, as previously described [18]. Statistical significance was set at p = 0.05.…”

“…Its development has been widely associated with genetic mutations, diet, inflammatory conditions, and dysbiosis [17]. The secondary objective of the study was to determine the correlation of the presence of, previously investigated by our group, toll-like receptors (TLRs) [18] and vitamin D receptors (VDRs) polymorphisms [19] with the detection of microbial DNA fragments in the blood of CRC patients. Table 1 and Data S1 summarize the demographics of all CRC patients enrolled in the study.…”