Modulation of the prostaglandin-endoperoxide synthase 2 gene expression by variant haplotypes: influence of the 3′-untranslated region

Abstract

The inducible inflammatory enzyme cycloxigenase-2 is up-regulated in cancer, and favors tumor progression. Cycloxigenase-2 is encoded by the prostaglandin-endoperoxide synthase 2 (PTGS2) gene, which presents sequence variations in the promoter region (PR) and in the 3′-untranslated region (3′-UTR). Different PR (rs689465, rs689466, rs20417) and 3′-UTR (rs5275) variants were generated by site-directed mutagenesis, and combined in haplotypes to access expression levels using a reporter system (luciferase) in human cells (MCF-7 and HEK293FT). Luciferase activity did not differ significantly among PTGS2 PR constructs, except for pAAC (containing variant allele rs20417 C), with 40% less activity than pAAG (wild-type sequence) in MCF-7 cells (P<0.01). Despite the lack of individual significant differences, PTGS2 PR constructs enclosing rs689466 G (pAGG and pAGC) showed an approximate two-fold increase in luciferase activity when compared to those containing rs689466 A (pAAG, pGAC, pAAC and pGAG) in both cell lines (P<0.001 for MCF-7 and P=0.03 for HEK293FT). The effect of PTGS2 3′-UTR sequences varied between MCF-7 and HEK293FT: MCF-7 cells showed significant reduction (40–60%) in luciferase activity (at least P<0.01), whereas HEK293FT cells showed more diverse results, with an average 2-fold increase when combined constructs (PR and 3′-UTR) were compared to respective parental PR sequences. The contribution of 3′-UTR variant (rs5275) was not consistent in either cell line. Despite the modulation of the 3′-UTR, with variable effects of rs5275, the enhancing transcriptional effect of rs689466 G was still detectable (P<0.0001 in MCF-7 or P=0.03 in HEK293FT cells).

Association of BTLA rs1982809 polymorphism with lung cancer risk in Tunisian population

“…Many studies found that genetic variations in 3’‐UTR nearby region may modify miRNA binding sites, which may affect miRNA‐mRNA interactions and thus, may modulate protein expression (Li et al., 2019; Moszyńska et al., 2017; Piranda et al., 2017). A previous study conducted by Karabon et al.…”

“…Currently, the following BTLA single‐nucleotide polymorphisms (SNPs): rs1982809 (A > G), rs9288952 (G > A), rs9288953 (C > T) were the most described in literature for their association with different diseases. The rs1982809 SNP is situated in the 3′‐untranslated region (3′‐UTR), where genetic variants in this region may modify miRNA binding sites and may affect miRNA‐mRNA interactions (Moszyńska, Gebert, Collawn, & Bartoszewski, 2017; Piranda, Abreu, Freitas‐Alves, de Carvalho, & Vianna‐Jorge, 2017). Many studies related to the rs1982809 SNP have described its association with chronic lymphocytic leukaemia (CLL) and with renal cell carcinoma (RCC) (Karabon et al., 2016; Partyka et al., 2016).…”

The effects of genotype on inflammatory response in hippocampal progenitor cells: A computational approach

“…(2020) AG genotype correlated with increased risk of Major Depressive Disorder in female subjects Moore et al. (2012) C allele was associated with COX2 overexpression by disrupting micro-RNA-mediated mRNA degradation (not replicated by Piranda et al. (2017) ) rs1800630 (= -863C/A) TNF = LTA Chronic inflammatory response, neurogenesis CC (homozygous reference) Chen et al.…”

“…For one, findings in previous experiments are contradictory in some cases. For instance, while there is some evidence that rs5275 (PTGS2) leads to COX2 overexpression ( Moore et al., 2012 ), another study did not find this effect ( Piranda et al., 2017 ). A further example is rs11666254 (FPR2) which has been linked to both neuroprotective and neurotoxic effects in that it downregulates FPR2 and simultaneously increases TNFα expression ( Zhang et al., 2017a ).…”

“…For the COX2 variant rs5275, the HPC cell line carries the heterozygous genotype (AG). Existing literature on this variation has found an upregulation of COX2 expression with the G allele ( Moore et al., 2012 ), although this finding was not replicated by Piranda et al. (2017) .…”