Variations in the interferon and TLR3 genes may be associated with susceptibility to systemic lupus erythematosus and its clinical presentation.

The study aimed to explore the pontential impact of 10 polymorphisms within IFN-α, IFN-ß1, IFN-γ and TLR3 genes on SLE phenotype and susceptibility and to study the relationship between specific genotypes and clinics. Whole blood samples from SLE patients and healthy controls was obtained. DNA was extracted from the peripheral blood by the QIAamp DNA Blood Mini Kit (Qiagen). The quality and quantity of isolated DNA was estimated by the Quawell Q5000 spectrophotometer. We genotyped SLE patients and healthy subjects using real-time PCR (QuantStudio 5 thermocycler). The study suggests that IFN-γ rs2069705, IFN-γ rs2069718 and IFN-α rs3758236 polymorphisms have a protective role in SLE. We observed relations between TLR3 rs3775292, IFN-ß1 rs7873167, IFN-γ rs2069705, TLR3 rs3775291 and TLR3 rs5743305 polymorphisms and clinical picture of SLE patients. We found associations between the IFN-α rs3758236, IFN-γ rs2069705, IFN-γ rs2069718, IFN-γ rs1861493 and IFN-ß1 rs10964831 polymorphisms and the clinical manifestation of the SLE and/or its comorbidities. We perceived links between IFN-γ rs2069705, IFN-γ rs2069718, IFN-γ rs1861493, TLR3 rs3775291, TLR3 rs3775292 and TLR3 rs5743305 polymorphisms and the occurrence of autoantibodies. Our study presented the relationship between IFN and TLR gene polymorphisms with SLE susceptibility, phenotype and autoantibodies profile. This study propose that polymorphisms within interferons and TLR3 genes can be engaged in the SLE pathogenesis and course.

Tamoxifen epigenetically modulates CXCL12 expression in MCF-7 breast cancer cells.

The CXCL12 chemokine binds to the CXCR4 receptor and contributes to survival, proliferation, and migration of malignant cells. Recent reports indicate that breast cancer cells lacking expression of CXCL12 but exhibiting CXCR4 can metastasize to target organs that secrete CXCL12. We observed that Tamoxifen (Tam), similarly to 5-dAzaC, results in significantly increased levels of CXCL12 transcript and protein in MCF-7 breast cancer cells. Bisulfite sequencing suggests that Tam, similarly to 5-dAzaC, may increase CXCL12 expression via reduction in methylation of cytosine in the cytosine-guanosine (CpG) dinucleotide island of the CXCL12 promoter of MCF-7 cells. Our results, together with findings of other researches, may suggest that Tam epigenetically activates CXCL12 expression in breast cancer cells and can make these cells less susceptible to attraction by exogenous CXCL12 to metastasis sites.

Increased CXCR4 expression in AsPC1 pancreatic carcinoma cells with RNA interference-mediated knockdown of DNMT1 and DNMT3B.

The effect of DNA methylation on CXCR4 expression has been demonstrated in pancreatic cancer and melanoma cells, but little is known about the effect of DNA methyltransferases 1 and 3 (DNMT1 and DNMT3B) on CXCR4 expression. Employing lentiviral vectors, we created stable RNA interference-mediated knockdown of DNMT1 and DNMT3B in AsPC1 pancreatic cancer cells. Using reverse transcription real-time quantitative PCR and flow cytometric analysis, we evaluated the increase in the expression of CXCR4 transcript and protein levels in these cells. Bisulfite sequencing analysis showed that the level of promoter demethylation appeared more effective in cells with knockdown of DNMT1 than in those with DNMT3B knockdown. Furthermore, the combined RNA interference knockdown of both DNMT1 and DNMT3B increased promoter demethylation, leading to a slight increase in CXCR4 expression. However, the demethylating agent 5-Aza-2'-deoxycytidine exhibited the strongest effect on promoter demethylation, which correlated with the highest production of CXCR4 transcript and protein in AsPC1 cells. Our results indicate that DNMT1 plays the main role in maintenance of methylation of CXCR4 promoter, while DNMT3B may function as an accessory DNA methyltransferase to modulate CXCR4 expression in AsPC1 cells.