Bidirectional expression of Toll-like receptor 7 gene in urinary bladder cancer and urinary tract infection of Iraqi patients

Abstract

Gene expression of toll-like receptor 7 (TLR7) was determined in urinary bladder cancer and urinary tract infection (UTI) patients. Sixty-six UBC and 40 UTI patients, as well as 48 healthy control subjects, were profiled for TLR7 gene expression by reverse transcription quantitative polymerase chain reaction. Three TLR7 gene single nucleotide polymorphisms (SNPs: rs1634322, rs1731478 and rs5743733) were detected by DNA-sequencing, and their impact on the expression was also inspected. Results demonstrated a non-significant decreased expression of TLR7 in UBC patients compared to control, while a significant increased expression was recorded in UTI patients compared to UBC patients or control. Out of the three investigated SNPs, only rs5743733 SNP showed variation between UBC patients and control. The allele G was not detected in control males, while its frequency in male patients was 17.5% (Odds ratio: 10.83; 95% confidence interval: 0.64–182.13; uncorrected p = 0.029). In the case of UTI female patients, genotype frequencies of TLR7 gene SNPs showed no significant differences between patients and the corresponding control. The three SNPs had no significant impact on TLR7 gene expression in UBC male patients, while a significant impact was recorded in UTI female patients and male and female controls. In conclusion, TLR7 gene showed upregulated expression in the peripheral blood of UTI patients, while a down-regulation in UBC patients was suggested. The risk of UBC might also be influenced by SNPs in the first intron of TLR7 gene.