MicroRNA-22 Impairs Anti-Tumor Ability of Dendritic Cells by Targeting p38

Abstract

Dendritic cells (DCs) play a critical role in triggering anti-tumor immune responses. Their intracellular p38 signaling is of great importance in controlling DC activity. In this study, we identified microRNA-22 (miR-22) as a microRNA inhibiting p38 protein expression by directly binding to the 3’ untranslated region (3’UTR) of its mRNA. The p38 down-regulation further interfered with the synthesis of DC-derived IL-6 and the differentiation of DC-driven Th17 cells. Moreover, overexpression of miR-22 in DCs impaired their tumor-suppressing ability while miR-22 inhibitor could reverse this phenomenon and improve the curative effect of DC-based immunotherapy. Thus, our results highlight a suppressive role for miR-22 in the process of DC-invoked anti-tumor immunity and that blocking this microRNA provides a new strategy for generating potent DC vaccines for patients with cancer.

Exosomal MicroRNAs in Milk from Mothers Delivering Preterm Infants Survive in Vitro Digestion and Are Taken Up by Human Intestinal Cells

“…This may constitute an important mechanism behind breast‐feeding protecting against enterocolitis in both preterm and term infants. In dendritic cells, miR‐22‐3p has been shown to affect production of IL‐6 which plays a significant role not only in the response to pathogens but also in the development of autoimmune disease . Similarly, miR‐148a‐3p, which was also highly expressed in preterm milk exosomes, is associated with decreasing the inflammatory response of cardiac tissue, as well as having a role in the differentiation of embryonic cells .…”

Circulating extracellular miR-22, miR-155, and miR-365 as candidate biomarkers to assess transport-related stress in turkeys

“…MiR-22 is one of the very few ubiquitously expressed miRNAs, and is likely to be involved in buffering cellular activities that are common to the vast majority cells. Among others activities, it is involved in the hematopoiesis process, in the down regulation of IL6 and in the differentiation of Th17 cells (Liang et al, 2015).…”

Role of microRNAs in the Regulation of Dendritic Cell Generation and Function

“…miR-22 is a miRNA that is highly conserved in vertebrate evolution and it is ubiquitously expressed in various tissues [80]. p38, a target of miR-22, is an important member of the MAPK family and, by regulating the activities of some interleukins, such as IL-6, it controls the process of tumor generation.…”

“…p38, a target of miR-22, is an important member of the MAPK family and, by regulating the activities of some interleukins, such as IL-6, it controls the process of tumor generation. In DCs, p38 has a crucial role in DC maturation and miR-22 negatively influences this factor, reducing its translation and also reducing IL-6 expression [80].…”