BACKGROUND Despite the important role that microRNAs (miRNAs) play in immunity and inflammation, their involvement in systemic sclerosis (SSc) remains poorly characterized. miRNA-155 (miR-155) plays a role in pulmonary fibrosis and its expression can be induced with interleukin (IL)-1β. SSc fibroblasts have activated inflammasomes that are integrally involved in mediating the myofibroblast phen...

The oncogenic role of microRNA-155 (miR-155) in leukemia is well established but its role in other cancers, especially breast cancer, is gradually emerging. In this study we examined the effect of mir-155 loss in a well-characterized spontaneous breast cancer mouse model where Brca1 and Trp53 are deleted by K14-Cre. miR-155 is known to be up-regulated in BRCA1-deficient tumors. Surprisingly, co...

miR-155 is a prominent microRNA (miRNA) that regulates genes involved in immunity and cancer-related pathways. miR-155 is overexpressed in lung cancer, which correlates with poor patient prognosis. It is unclear how miR-155 becomes increased in lung cancers and how this increase contributes to reduced patient survival. Here, we show that hypoxic conditions induce miR-155 expression in lung canc...

Several studies have indicated an important role for miR-155 in the pathogenesis of B-cell lymphoma. Highly elevated levels of miR-155 were indeed observed in most B-cell lymphomas with the exception of Burkitt lymphoma (BL). However, the molecular mechanisms that underlie the oncogenic role of miR-155 in B-cell lymphoma are not well understood. To identify the miR-155 targets relevant for B-ce...

MicroRNA-155 (miR-155) plays significant role in various physiological processes involving both innate and adaptive immunity. miR-155 expression level changes dynamically during various immune responses. However, current approaches for miR-155 detection at the RNA level do not precisely reflect the real-time activity. Herein, we generated a transgenic mouse line (R26-DTR-155T) for determination...

The anti-inflammatory cytokine interleukin-10 (IL-10) is essential for attenuating the inflammatory response, which includes reducing the expression of pro-inflammatory microRNA-155 (miR-155) in lipopolysaccharide (LPS) activated macrophages. miR-155 enhances the expression of pro-inflammatory cytokines such as TNFα and suppresses expression of anti-inflammatory molecules such as SOCS1. Therefo...

Myeloid-derived suppressor cells (MDSC) are one of the main cell populations that negatively regulate immune responses. However, the mechanism underlying the expansion of MDSC remains unclear. Using miRNA microarray and TaqMan probe-based quantitative RT-PCR assay, we identified microRNA (miR)-155 and miR-21 as the two most upregulated miRNAs during the induction of MDSC from the bone marrow ce...

MicroRNAs (miRNAs) have emerged as critical modulators of carcinogenesis and tumor progression. In the present work, we sought to identify the biological function of miR-155 as well as its underlying mechanism in clear cell renal cell carcinoma (ccRCC). We examined the expression of miR-155 in clear cell RCC (ccRCC) and adjacent normal tissues and then explored the roles of miR-155 both in vitr...

MicroRNA-155 (miR-155) has emerged as a critical regulator of immune cell development, function, and disease. However, the mechanistic basis for its impact on the hematopoietic system remains largely unresolved. Because miRNAs function by repressing specific mRNAs through direct 3'UTR interactions, we have searched for targets of miR-155 implicated in the regulation of hematopoiesis. In the pre...

MicroRNA-155 (miR-155) was previously found involved in the development of systemic lupus erythematosus (SLE) and other autoimmune diseases and the inflammatory response; however, the detailed mechanism of miR-155 in SLE is not fully understood. To explore the in vivo role of miR-155 in the pathogenesis of SLE, miR-155-deficient Fas(lpr/lpr) (miR-155(-/-)Fas(lpr/lpr)) mice were obtained by cros...