Variability, Expression, and Methylation of IL-6 and IL-8 Genes in Bladder Cancer Pathophysiology

Abstract

Bladder cancer (BC) is the 10th most common form of cancer globally, but its complete aetiology is still unknown. Nevertheless, there is evidence that chronic inflammation plays a role in the development and progression of BC. Therefore, the presented study aimed to detect a potential association between selected single nucleotide polymorphisms (SNPs)—rs1800797 and rs2069845 in IL-6 and rs2227307 in IL-8—and BC development, as well as to identify the impact of BC on the level of expression and methylation of IL-6 and IL-8 promoters in PBMCs with the use of the TaqMan SNP genotyping assay, TaqMan gene expression assay, and methylation-sensitive high-resolution melting techniques. We did not find any association between the genotypes and combined genotypes of all studied polymorphisms and the occurrence of BC. However, we found that BC patients were characterised by decreased IL-6 and IL-8 mRNA expression levels compared to the controls. Additionally, the methylation status of the IL-6 promoter was higher in controls than in BC patients. Our findings suggest that inflammation may be involved in the development and progression of BC.

Polymorphic variations and mRNA expression of the genes encoding interleukins as well as enzymes of oxidative and nitrative stresses as a potential risk of nephrolithiasis development

“…The recruitment period for this study covered November 16, 2021, to December 20, 2022. The qualification procedure was the same as described in our publication [ 27 ]. Nevertheless, additional exclusion criteria were applied which included: using drugs such as estrogens, progesterone, glucocorticoids, diuretics, anticonvulsants, vitamin D, antiacid drugs, heparin, prostaglandin preparations, etc.…”

“…Additionally, all participants were asked to complete the same structural questionnaire from previously published articles to determine demographic and potential risk factors for urolithiasis, including age, lifestyle habits (e.g. g. the amount of fluids consumed daily, including coffee, type of diet), including smoking, body mass index (BMI), and co-occurrence disease (e. g. hypertension, diabetes, hypercholesterolemia) [ 27 ]. As in our previous studies [ 27 , 28 ], the participation in the study had voluntary character and qualified individuals were native Poles from central Poland (not related) and were selected randomly without replacement sampling.…”

“…g. the amount of fluids consumed daily, including coffee, type of diet), including smoking, body mass index (BMI), and co-occurrence disease (e. g. hypertension, diabetes, hypercholesterolemia) [ 27 ]. As in our previous studies [ 27 , 28 ], the participation in the study had voluntary character and qualified individuals were native Poles from central Poland (not related) and were selected randomly without replacement sampling. Importantly, before deciding to participate in the experiment, all individuals were informed of the purpose and assured of the voluntary nature of the experiment and guaranteed that their personal data would be kept secret.…”

“…After qualifying for participation in the study (in the years 2021–2022) and giving written consent to participate in the study, whole blood was collected from each participant from the cubital vein into a properly coded tube and stored at -20°C until the isolation of the genetic material. Genomic DNA and total RNA were isolated with a commercial kit—DNA/RNA Extracol Kit (EURX, Gdansk, Poland) as previously described by Grębowski et al (2023) [ 27 ].…”

“…After the isolation of the genetic material from whole blood, we proceeded to genotype all the samples for all chosen genetic variants according to the protocol described in previous our publications [ 27 , 28 ]. Briefly, real-time PCR was performed in a CFX96™ Real-Time PCR Detection System Thermal Cycler (Bio-Rad Laboratories, Inc., Hercules, CA, USA), using the TaqMan allele-specific discrimination assay, TaqMan® SNP Genotyping Assay (Thermo Fisher Scientific, Waltham, MA, USA), and RT PCR Mix Probe (A&A Biotechnology, Gdynia, Poland).…”