Long non-coding RNA DQ786243 modulates the induction and function of CD4⁺ Treg cells through Foxp3-miR-146a-NF-κB axis: Implications for alleviating oral lichen planus

The present study was aimed to investigate the effects of the long non-coding RNA DQ786243 in the regulation of Treg cells in oral lichen planus (OLP), as well as to evaluate its potential molecular mechanisms. Here we found that the expression of DQ786243 and Foxp3 were both overexpressed in the CD4⁺ cells from the peripheral blood of OLP patients, and their expression was positively correlated. Meanwhile, compared with the normal CD4⁺ cells, the frequency of Foxp3⁺ Treg cells in the OLP CD4⁺ cells was significantly higher. DQ786243 overexpression in normal CD4⁺ cells resulted in the upregulation of Foxp3 and the higher frequency of Foxp3⁺ Treg cells. Furthermore, we found that the induction of Foxp3⁺ Treg cells by DQ786243 significantly increased its suppressive function, and suppressed the function of other CD4⁺ T cells such as Th1 and Th17 by decreasing the levels of IFN-γ and IL-17. Moreover, we found that DQ786243 overexpression markedly elevated the expression of miR-146a via regulating Foxp3, and thus inhibiting the NF-κB signaling. In conclusion, these findings indicate that DQ786243 may regulate the induction and function of CD4⁺ Treg cells through Foxp3-miR-146a-NF-κB axis, implicating a novel insight into understanding the progression of OLP.