MIR155 Regulation of Ubiquilin1 and Ubiquilin2: Implications in Cellular Protection and Tumorigenesis12
نویسندگان
چکیده
Ubiquilin (UBQLN) proteins are adaptors thought to link ubiquitinated proteins to the proteasome. However, our lab has recently reported a previously unappreciated role for loss of UBQLN in lung cancer progression. In fact, UBQLN genes are lost in over 50% of lung cancer samples examined. However, a reason for the loss of UBQLN has not been proposed, nor has a selective pressure that could lead to deletion of UBQLN been reported. Diesel Exhaust Particles (DEP) are a major concern in the large cities of developing nations and DEP exposed populations are at an increased risk of developing a number of illnesses, including lung cancer. A connection between DEP and UBQLN has never been examined. In the present study, we determined the effect of DEP on lung cell lines and were interested to determine if UBQLN proteins could potentially play a protective role following treatment with DEP. Interestingly, we found that DEP treated cells have increased expression of UBQLN proteins. In fact, over-expression of UBQLN was capable of protecting cells from DEP toxicity. To investigate the mechanism by which DEP leads to increased UBQLN protein levels, we identified and interrogated microRNAs that were predicted to regulate UBQLN mRNA. We found that DEP decreases the oncogenic microRNA, MIR155. Further, we showed that MIR155 regulates the mRNA of UBQLN1 and UBQLN2 in cells, such that increased MIR155 expression increased cell invasion, migration, wound formation and clonogenicity in UBQLN-loss dependent manner. This is the first report of an environmental carcinogen regulating expression of UBQLN proteins. We show that exposure of cells to DEP causes an increase in UBQLN levels and that MIR155 regulates mRNA of UBQLN. Thus, we propose that DEP-induced repression of MIR155 leads to increased UBQLN levels, which in turn may be a selective pressure on lung cells to lose UBQLN1.
منابع مشابه
Klotho Protein,A Biomarker for AKI
Klotho is an anti-aging single-pass membrane protein that is mainly produced in the kidney. The level of soluble klotho decreases with age and the klotho gene is associated with an increased risk of age-related diseases, such as diabetes, skin atrophy, chronic kidney disease, ataxia and cancer. The klotho gene is composed of five exons and encodes a membrane glycoprotein located in the plasma ...
متن کاملHealth Insecurity and Social Protection: Pathways, Gaps, and Their Implications on Health Outcomes and Poverty
Health insecurity has emerged as a major concern among health policy-makers particularly in low- and middle-income countries (LMICs). It includes the inability to secure adequate healthcare today and the risk of being unable to do so in the future as well as impoverishing healthcare expenditure. The increasing health insecurity among 150 million of the world’s poor has moved social protection i...
متن کاملRegulation of Bone Metabolism
Bone is formed through the processes of endochondral and intramembranous ossification. In endochondral ossification primary mesenchymal cells differentiate to chondrocytes and then are progressively substituted by bone, while in intramembranous ossification mesenchymal stem cells (MSCs) differentiate directly into osteoblasts to form bone. The steps of osteogenic proliferation, differentiation,...
متن کاملHost miR155 promotes tumor growth through a myeloid-derived suppressor cell-dependent mechanism.
miR155 is a regulator of immune cell development and function that is generally thought to be immunostimulatory. However, we report here that genetic ablation of miR155 renders mice resistant to chemical carcinogenesis and the growth of several transplanted tumors, suggesting that miR155 functions in immunosuppression and tumor promotion. Host miR155 deficiency promoted overall antitumor immuni...
متن کامل