MiR-125a-5p increases cellular DNA damage of aging males and perturbs stage-specific embryo development via Rbm38-p53 signaling.
Ontology highlight
ABSTRACT:
SUBMITTER: Liang K
PROVIDER: S-EPMC8672779 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:Rbm38 is a p53 target and an RNA-binding protein known to suppress p53 translation by preventing eukaryotic translation initiation factor 4E (eIF4E) from binding to p53 mRNA. In this study, we show that synthetic peptides corresponding to the binding interface between Rbm38 and eIF4E, including an 8 amino acid peptide (Pep8) derived from Rbm38, are effective in relieving Rbm38-mediated repression of p53. Molecular simulations showed that Ser-6 in Pep8 forms a hydrogen bond with Asp-202 in eIF4E. Substitution of Ser-6 with Lys, but not with Asp, enhanced the ability of Pep8 to inhibit the Rbm38-eIF4E complex. Importantly, Pep8 alone or together with a low dose of doxorubicin potently induced p53 expression and suppressed colony and tumor sphere formation and xenograft tumors in Rbm38- and p53-dependent manners. Together, we conclude that modulating the Rbm38-eIF4E complex may be explored as a therapeutic strategy for cancers that carry wild-type p53. SIGNIFICANCE: Disruption of the Rbm38-eIF4E complex via synthetic peptides induces wild-type p53 expression, suppresses tumor growth and progression, and may serve as a novel cancer therapeutic strategy.
| S-EPMC6377842 | biostudies-literature
Project description:Increasing evidence suggests that microRNAs (miRNAs) play important roles in impaired endothelial cell (EC) angiogenesis during aging. However, their exact roles in the aging process remain unclear. We aimed to determine whether miRNAs cause angiogenesis defects in ECs during aging and to uncover the underlying mechanisms. To study the miRNA-induced changes in ECs during aging, we performed microarray analyses on arterial ECs collected from young and aging mice. Using qRT-PCR, we showed that microRNA-125a-5p (mir-125a-5p) expression was approximately 2.9 times higher in old endothelial cells (OECs) compared with samples collected from young animals. Western blot assays showed a lower expression level of an mir-125a-5p target known as related transcriptional enhancer factor-1 (RTEF-1) in OECs compared with its expression levels in young cells. Overexpression of mir-125a-5p in young endothelial cells (YECs) using pre-mir-125a-5p caused the downregulation of RTEF-1, endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF) and resulted in impaired angiogenesis, as evidenced by spheroid sprouting and tube formation assays in vitro. Conversely, repression of mir-125a-5p in OECs using anti-mir-125a-5p increased RTEF-1, eNOS and VEGF expression and improved EC angiogenesis. Importantly, impaired angiogenesis caused by knock-down of RTEF-1 was not efficiently rescued by anti-mir-125a-5p. Dual-luciferase reporter gene analysis showed that RTEF-1 is a direct target of mir-125a-5p, which regulates angiogenesis by repressing RTEF-1 expression and modulating eNOS and VEGF expression. These findings indicate that mir-125a-5p and RTEF-1 are potential therapeutic targets for improving EC-mediated angiogenesis in elderly individuals.
| S-EPMC4331751 | biostudies-literature
Project description:RNA-binding motif protein 38 (Rbm38), also called RNPC1 [RNA-binding region (RNP1, RRM) containing 1], is a target of the p53 family and modulates p53 expression via mRNA translation. To investigate the biological function of Rbm38 in vivo, we generated an Rbm38-null mouse model. We showed that mice deficient in Rbm38 exhibit signs of accelerated aging and are prone to hematopoietic defects and spontaneous tumors. To determine the biological significance of the p53-Rbm38 loop, we showed that Rbm38 deficiency enhances accumulation of p53 induced by ionizing radiation (IR) and sensitizes mice to IR-induced lethality in a p53-dependent manner. Most importantly, Rbm38 deficiency markedly decreases the tumor penetrance in mice heterozygous for p53 via enhanced p53 expression. Interestingly, we found that Rbm38 deficiency shortens the life span of, and promotes lymphomagenesis in, mice deficient in p53. These results provide genetic evidence that Rbm38 is necessary for normal hematopoiesis and for suppressing accelerated aging and tumorigenesis. Thus, the p53-Rbm38 axis might be explored for extending longevity and for tumor suppression.
| S-EPMC4284600 | biostudies-literature
Project description:Hepatocellular carcinoma (HCC) is one of the most prevalent and deadly cancers world-wide. miR-125a-5p is a tumor suppressor in HCC and other cancers, but its mechanisms of action during HCC tumorigenesis remain largely unknown. In this study, we found that miR-125a-5p expression was significantly lower in HCC tissues and cell lines than matched normal tissues and liver cells. miR-125a-5p overexpression inhibited HCC cell proliferation and induced apoptosis in vitro and in vivo, while miR-125a-5p knockdown had the opposite effects. In addition, PTPN1 and MAP3K11 were identified as targets of miR-125a-5p. Knocking down PTPN1 and MAP3K11 activated the JNK MAPK signaling pathway to suppress HCC cell proliferation and induce apoptosis. Our findings suggest that miR-125a-5p may be a useful therapeutic target for treatment of HCC patients.
| S-EPMC6781988 | biostudies-literature
Project description:Calorie restriction (CR) is a dietary intervention known to delay aging. In order, to understand molecular mechanisms of CR, we analyzed the expression of 983 MicroRNAs (miRNAs) in the liver of female mice after 2 years of 30% CR using micro-array. 16 miRNAs demonstrated significant changes in their expression upon CR in comparison with age-matched control. mmu-miR-125a-5p (miR-125a-5p) was significantly upregulated upon CR, and in agreement with this, the expression of mRNAs for its three predicted target genes: Stat3, Casp2, and Stard13 was significantly downregulated in the liver of CR animals. The expression of precursor miRNA for miR-125a-5p was also upregulated upon CR, which suggests its regulation at the level of transcription. Upon aging miR-125a-5p expression was downregulated while the expression of its target genes was upregulated. Thus, CR prevented age-associated changes in the expression of miR-125a-5p and its targets. We propose that miR-125a-5p dependent downregulation of Stat3, Casp2, and Stard13 contributes to the calorie restriction-mediated delay of aging.
| S-EPMC5559175 | biostudies-literature
Project description:Systemic juvenile idiopathic arthritis (SJIA) is a severe childhood arthropathy with features of autoinflammation. Monocytes and macrophages in SJIA have a complex phenotype with both pro- and anti-inflammatory properties that combine features of several well characterized in vitro conditions used to activate macrophages. An important anti-inflammatory phenotype is expression of CD163, a scavenger receptor that sequesters toxic pro-inflammatory complexes that is highly expressed in both active SJIA and macrophage activation syndrome (MAS). CD163 is most strongly upregulated by IL-10 (M(IL-10)), and not by other conditions that reflect features seen in SJIA monocytes such as M(LPS+IC). MicroRNA play key roles balancing and integrating cellular signals such as those in macrophage polarization, and as such we hypothesize microRNA regulate macrophage functional responses in SJIA including CD163 expression in vitro. We find that two microRNA previously found to be elevated in active SJIA, miR-125a-5p and miR-181c, significantly reduced macrophage CD163 expression through two distinct mechanisms. Neither microRNA was elevated in M(IL-10) with robust CD163 expression, but were instead induced in M(LPS+IC) where they restricted CD163 mRNA expression. Mir-181 species directly targeted CD163 mRNA for degradation. In contrast, transcriptome analysis of miR-125a-5p overexpression identified “cytokine-cytokine receptor interactions” as the most significantly repressed gene pathway, including decreased IL10RA, which is required for IL-10-mediated CD163 expression. Finally, overexpression of miR-181c inhibited CD163 anti-inflammatory responses to hemoglobin or high mobility group box 1 complexes. Together, these data show that microRNA utilize multiple mechanisms to integrate well characterized polarization phenotypes and regulate macrophage functional properties seen in SJIA.
2018-04-12 | GSE104853 | GEO
Project description:MicroRNAs (miRNAs) interact with 3'-untranslated regions of messenger RNAs to restrict expression of most protein-coding genes during normal development and cancer. RNA-binding proteins (RBPs) can control the biogenesis, stability and activity of miRNAs. Here we identify RBM38 in a genetic screen for RBPs whose expression controls miRNA access to target mRNAs. RBM38 is induced by p53 and its ability to modulate miRNA-mediated repression is required for proper p53 function. In contrast, RBM38 shows lower propensity to block the action of the p53-controlled miR-34a on SIRT1. Target selectivity is determined by the interaction of RBM38 with uridine-rich regions near miRNA target sequences. Furthermore, in large cohorts of human breast cancer, reduced RBM38 expression by promoter hypermethylation correlates with wild-type p53 status. Thus, our results indicate a novel layer of p53 gene regulation, which is required for its tumour suppressive function.
| S-EPMC3221330 | biostudies-literature
Project description:The present study aimed to screen and analyze the differential expression spectrum of microRNA (miRNA) between laryngeal cancer tissue and surrounding normal laryngeal mucosa in order to provide an indication for further study to determine the role of miRNA in the initiation and development of laryngeal cancer. A total of 42 pairs of specimens of laryngeal carcinoma tissues and adjacent normal laryngeal mucosa were collected. A total of 10 pairs of specimens were randomly selected for miRNA microarray gene chip analysis, and the remaining 32 pairs of specimens were used for reverse transcription-quantitative polymerase chain reaction (RT-qPCR) verification to identify miRNA that were differentially expressed in laryngeal cancer tissues. Methylthiazolyldiphenyl-tetrazolium bromide and clone formation assays were utilized to elucidate the physiological relevance of the miRNA miR-125a-5p on the proliferation of laryngeal cancer human epithelial type 2 (Hep2) cells. Results demonstrated that the expression levels of six miRNA were significantly downregulated in laryngeal carcinoma tissue, as identified by gene chip analysis and RT-qPCR (P<0.05). The six miRNA included let-7f-5p, miR-10a-5p, miR-125a-5p, miR-144-3p, miR-195-5p and miR-203. Compared with the control group, the proliferative ability of laryngeal cancer Hep2 cells was inhibited in a transfected miR-125a-mimics group. In contrast, proliferation was promoted in a transfected miR-125a-inhibitor group. In conclusion, the results of gene chip analysis were consistent with that of RT-qPCR. Results demonstrated that miRNA in laryngeal cancer and normal laryngeal mucosa exhibited evident differential expression, which may contribute to the laryngeal cancer incidence and invasion. miR-125a was able to inhibit the proliferation of Hep2 laryngeal cancer cells and, therefore, may serve as a novel target for laryngeal cancer biological therapy.
| S-EPMC5525897 | biostudies-other
Project description:Polμ is an error-prone PolX polymerase that contributes to classical NHEJ DNA repair. Mice lacking Polμ (Polμ(-/-)) show altered hematopoiesis homeostasis and DSB repair and a more pronounced nucleolytic resection of some V(D)J junctions. We previously showed that Polμ(-/-) mice have increased learning capacity at old ages, suggesting delayed brain aging. Here we investigated the effect of Polμ(-/-) deficiency on liver aging. We found that old Polμ(-/-) mice (>20 month) have greater liver regenerative capacity compared with wt animals. Old Polμ(-/-) liver showed reduced genomic instability and increased apoptosis resistance. However, Polμ(-/-) mice did not show an extended life span and other organs (e.g., heart) aged normally. Our results suggest that Polμ deficiency activates transcriptional networks that reduce constitutive apoptosis, leading to enhanced liver repair at old age.
| S-EPMC3972199 | biostudies-literature
Project description:The p63 transcription factor, a p53 family protein, regulates genes involved in various cellular processes, including cell growth and differentiation. We previously showed that RNA-binding motif protein (Rbm38) is a p63 target and, in turn, regulates p63α mRNA stability by binding to the AU/U-rich element in its 3'UTR. Interestingly, Rbm38 can be phosphorylated at serine 195, altering its ability to regulate mRNA translation. However, whether the Ser-195 phosphorylation affects Rbm38's ability to destabilize p63 mRNA remains unclear. Here, using MCF7 and HaCaT cells, we showed that ectopic expression of phosphomimetic Rbm38-S195D increases, whereas WT Rbm38 and nonphosphorylatable Rbm38-S195A decrease p63α protein and transcript levels. We also found that upon activation of glycogen synthase kinase 3β (GSK3β), phosphorylation of Rbm38 at Ser-195 is increased, enhancing p63α expression in an Rbm38-dependent manner. To confirm this, we generated mouse embryo fibroblasts (MEFs) in which Ser-193 in mouse Rbm38 (equivalent to Ser-195 in human Rbm38) was substituted with aspartic acid (Rbm38S193D/S193D ) or alanine (Rbm38S193A/S193A ). We observed that the p63 transcript level was increased in Rbm38S193D/S193D MEFs, but decreased in Rbm38S193A/S193A MEFs. Mechanistically, we found that WT Rbm38, but not Rbm38-S195D, is required for p63 mRNA degradation mediated by microRNA 203 (miR203). Furthermore, we noted that Argonaute 2 (Ago2), a key regulator in microRNA-mediated mRNA decay, associates with WT Rbm38, and this association was reduced by Ser-195 phosphorylation. Together, our results reveal a critical mechanism by which Ser-195 phosphorylation in Rbm38 increases p63 expression by attenuating the association of Rbm38 with the Ago2-miR203 complex.
| S-EPMC6378984 | biostudies-literature