BMSC-derived exosomal miR-219-5p alleviates ferroptosis in neuronal cells caused by spinal cord injury via the UBE2Z/NRF2 pathway.

OBJECTIVE: The aim of this study was to investigate the molecular mechanism of exosomal miR-219-5p derived from bone marrow mesenchymal stem cells (BMSCs) in the treatment of spinal cord injury (SCI). METHODS: Basso Beattie Bresnahan (BBB) score and tissue staining were used to assess SCI and neuronal survival in rats. The contents of Fe2+, malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) were detected by a kit. The expression levels of ubiquitin-conjugating enzyme E2 Z (UBE2Z), nuclear factor erythroid 2-related Factor 2 (NRF2) and ferroptosis-related proteins were detected by Western blotting. In addition, the ability of BMSC-derived exosomes to inhibit ferroptosis in neuronal cells in rats with SCI was validated by in vivo injection of ferroptosis inhibitors/inducers. RESULTS: In this study, we found that miR-219-5p-rich BMSC-derived exosomes inhibited ferroptosis in SCI rats and that the alleviating effect of BMSC-Exos on SCI was achieved by inhibiting the ferroptosis signaling pathway and that NRF2 played a key role in this process. Our study confirmed that BMSC exosome-specific delivery of miR-219-5p can target UBE2Z to regulate its stability and that overexpression of UBE2Z reverses miR-219-5p regulation of NRF2. In addition, in vivo experiments showed that BMSC exosomes alleviated ferroptosis in neuronal SCI progression, and inhibiting the expression of miR-219-5p in BMSCs reduced the alleviating effect of exosomes on ferroptosis in neuronal cells and SCI. CONCLUSION: miR-219-5p in BMSC-derived exosomes can repair the injured spinal cord. In addition, miR-219-5p alleviates ferroptosis in neuronal cells induced by SCI through the UBE2Z/NRF2 pathway.

miR-219a-5p inhibits the pyroptosis in knee osteoarthritis by inactivating the NLRP3 signaling via targeting FBXO3.

PURPOSE: This work was to identify the function and mechanism of miR-219a-5p in regulating knee osteoarthritis (KOA). METHODS: Rat fibroblast-like synoviocytes (FLSs) were isolated to construct KOA cell model by lipopolysaccharide and adenosine triphosphate treatment. miR-219a-5p and FBXO3 expression in FLSs was modulated by transfection. Flow cytometry was executed to research FLSs apoptosis. Caspase-1 and IL-1ß expression in FLSs was researched by immunofluorescence. The binding between miR-219a-5p and FBXO3 was identified by dual luciferase reporter gene assay. KOA rat model and miR-219a-5p up-modulation KOA rat model were constructed. Step size of rats was analyzed. Knee joints of rats were experienced Safranin O-fast green staining to evaluate the knee joint injury. FBXO3, pyroptosis-associated proteins, and IL-1ß and IL-18 expression in FLSs and articular cartilage tissues of rats were assessed by Western blot, qRT-PCR and Enzyme-linked immunosorbent assay. RESULTS: KOA cell model had higher apoptosis percentage, expression of pyroptosis-associated proteins, and IL-1ß and IL-18 level. miR-219a-5p up-modulation decreased the above indicators, whereas miR-219a-5p down-modulation increased the above indicators. FBXO3 expression was directly repressed by miR-219a-5p. Loss of FBXO3 suppressed the above indicators. FBXO3 counteracted the suppression of miR-219a-5p on the above indicators. miR-219a-5p agomir attenuated knee joint injury, increased step size of KOA rats, and reduced FBXO3, pyroptosis-associated proteins and level of IL-1ß and IL-18 in the articular cartilage tissues of KOA rats. CONCLUSION: miR-219a-5p suppressed the pyroptosis in KOA by inactivating the NLRP3 signaling via targeting FBXO3, which might be a promising target for ameliorating KOA in the clinic.

Long noncoding RNA XIST knockdown relieves the injury of microglia cells after spinal cord injury by sponging miR-219-5p.

Long noncoding RNAs have been demonstrated to play crucial roles in the pathogenesis of spinal cord injury (SCI). In this study, we aimed to explore the roles and underlying mechanisms of lncRNA X-inactive specific transcript (XIST) in SCI progression. SCI mice model was constructed and evaluated by the Basso-Beattie-Bresnahan method. The SCI cell model was constructed by treating BV2 cells with lipopolysaccharide (LPS). The levels of XIST and miR-219-5p were determined by the reverse transcription quantitative polymerase chain reaction. The concentrations of inflammatory cytokines were measured by enzyme-linked immunosorbent assay. Protein levels were measured via western blot assay. Cell viability and apoptosis were evaluated by cell counting kit-8 assay and flow cytometry analysis, respectively. The relationship between XIST and miR-219-5p was analyzed by online tool starBase, dual-luciferase reporter assay, and RNA immunoprecipitation assay. As a result, the XIST level was enhanced and the miR-219-5p level was declined in the SCI mice model. XIST was also upregulated in LPS-induced BV2 cells. LPS treatment restrained BV2 cell viability and accelerated apoptosis and inflammatory response. XIST knockdown effectively weakened LPS-induced BV2 cell injury. miR-219-5p was identified as a target of XIST. Moreover, inhibition of miR-219-5p restored the impacts of XIST knockdown on cell viability, apoptosis, and inflammation in LPS-treated BV2 cells. In addition, LPS-induced XIST promoted the activation of the nuclear factor-κB (NF-κB) pathway by sponging miR-219-5p. In conclusion, XIST silencing promoted microglial cell viability and repressed apoptosis and inflammation by sponging miR-219-5p, thus promoting the recovery of SCI.

LINC00461 Promoted Endometrial Carcinoma Growth and Migration by Targeting MicroRNA-219-5p/Cyclooxygenase-2 Signaling Axis.

Endometrial carcinoma (EC) ranks as the most common female genital cancer in developed countries. Lately, more and more long noncoding RNAs (lncRNAs) have been identified as vital regulators in numerous physiological and pathological processes, including EC. However, the expression pattern and precise functions of different lncRNAs in EC remain unclear. In this study, we reported LINC00461 was upregulated in EC patient tissues and cell lines. In addition, LINC00461 knockdown could remarkably suppress cell proliferation, cell cycle progression, cell migration, and promote cell apoptosis in EC cells. We discovered LINC00461 could sponge microRNA-219-5p (miR-219-5p) and suppress its expression, thereby upregulating expression level of miR-219-5p's target, cyclooxygenase-2 (COX-2). In vivo animal models, LINC00461 knockdown inhibited tumor growth by increasing miR-219-5p level and reducing COX-2 expression, thus confirming LINC00461 functions as an oncogene in EC. In this study, a novel regulatory role of LINC00461/miR-219-5p/COX-2 axis was systematically investigated in context of EC, with the aim to provide promising intervention targets for EC therapy from bench to clinic. [Formula: see text].

microRNA-219-5p targets NEK6 to inhibit hepatocellular carcinoma progression.

MicroRNA-219-5p (miR-219-5p) is a key post-transcriptional regulator of gene expression that is known to regulate cancer progression, but its role in the context of hepatocellular carcinoma (HCC) remains to be fully elucidated. Herein, it was found that this miRNA functions as a tumor suppressor. Specifically, significant decreases in miR-219-5p expression were detected in HCC cells and patient serum samples relative to that found in the serum of 15 healthy people, and it was concluded that miR-219-5p overexpression was sufficient to impair HCC cell proliferation in vitro and vivo and migration in vitro. At the mechanistic level, it was found that miR-219-5p was able to suppress the expression of NEK6 (never in mitosis gene a-related kinase 6), thereby resulting in dysregulated ß-catenin/c-Myc-regulated gene expression. When NEK6 was overexpressed in HCC cells, this was sufficient to reverse the inhibitory impact of miR-219-5p on HCC cell proliferation both in vitro and vivo and metastasis in vitro. Bioinformatics analyses were also conducted, and both miR-219-5p and Nek6 were linked to disease progression in HCC patients with advanced disease. More importantly, the serum specimen data showed that reduced perioperative plasma miR-219-5p correlated significantly with increased risk of early recurrence after curative hepatectomy, whereas it was opposed to NEK6. Together, these findings highlight miR-219-5p as a potentially valuable diagnostic biomarker that can potentially be leveraged to improve clinical outcomes in HCC patients.

Propofol-induced miR-219-5p inhibits growth and invasion of hepatocellular carcinoma through suppression of GPC3-mediated Wnt/ß-catenin signalling activation.

Propofol is one of the most extensively used intravenous anaesthetic agents, which has been found to improve the surgical intervention outcome of several types of cancer, including hepatocellular carcinoma (HCC). Additionally, in vitro and in vivo experiments have also indicated that propofol affects the biological behaviour of HCC. However, the underlying mechanisms of the surgical resection of HCC with propofol have not been fully understood. In the present study, we aimed to investigate the underlying mechanism of propofol inhibition of the growth and invasion of HCC cells. Our results showed that treatment with propofol suppressed the proliferation, invasion and migration of HCC in vitro. The subcutaneous xenograft tumour and orthotopic xenograft tumour experiments in nude mice showed that propofol significantly decreased tumour volumes, growth rates and the liver orthotopic xenograft tumour in vivo. Furthermore, the underlying mechanism investigations of the suppressive effects of propofol on HCC cells revealed that propofol treatment upregulated the expression levels of the candidate tumour suppressor miR-219-5p. Silencing of propofol-induced miR-219-5p using anti-miR-219-5p abrogated the inhibitory effects on the proliferation, migration and invasion of HCC cells exerted by propofol treatment. Additionally, we demonstrated that propofol reversed the epithelial-mesenchymal transition of Huh7 and SMMC7721 cells via miR-219-5p induction. The molecular mechanism behind these findings is that propofol-induced miR-219-5p inhibits HCC cell progression by targeting glypican-3 and subsequently results in the inhibition of Wnt/ß-catenin signalling. Taken together, our study provides new insights into the advantages of the surgical intervention of HCC with propofol anaesthetization.

MiR-219-5p suppresses cell proliferation and cell cycle progression in esophageal squamous cell carcinoma by targeting CCNA2.

BACKGROUND: We investigated the potential regulatory role of miR-219-5p in esophageal squamous cell carcinoma (ESCC) and looked at the underlying mechanisms in ESCC. METHODS: Real-time PCR was used to determine the levels of miR-219-5p in ESCC tissues and cell lines. The effects of miR-219-5p and cyclin A2 (CCNA2) on cell proliferation and cell cycle progression were evaluated using MTT, colony formation and flow cytometry assays with ESCC cell lines EC9706 and TE-9. Bioinformatics techniques and the luciferase reporter assay were applied to validate CCNA2 as the miR-219-5p target in ESCC cells. The mRNA and protein levels of CCNA2 were measured using real-time PCR and western blotting. RESULTS: MiR-219-5p expression was significantly lower in ESCC tissues and cells than in healthy tissues. Upregulation of miR-219-5p repressed cell proliferation and induced cell cycle arrest at the G2/M phase. CCNA2 was identified and confirmed as a direct downstream target of miR-219-5p and its expression negatively correlated with miR-219-5p profiles in ESCC tissues. Knockdown of CCNA2 potentiated the effects of miR-219-5p on cell proliferation and cell cycle distribution. CONCLUSIONS: Our results demonstrate that miR-219-5p might function as a tumor suppressor by directly targeting CCNA2 expression. It could serve as a new therapeutic target for ESCC.

miR-219-5p inhibits tau phosphorylation by targeting TTBK1 and GSK-3ß in Alzheimer's disease.

As the most common neurodegenerative disease, Alzheimer's disease (AD) is characterized by memory, perception, and behavioral damage, which may ultimately lead to emotional fluctuation and even lethal delirium. Increasing studies indicate that microRNAs (miRNAs) are associated with pathological features of AD. However, the role of miR-219-5p in AD progression is still unclear. In this study, the functions of miR-219-5p were analyzed in vitro and in vivo. miR-219-5p was notably overexpressed in brain tissues of patients with AD. The overexpression of miR-219-5p activated the phosphorylation of Tau-Ser198, Tau-Ser199, Tau-Ser201, and Tau-Ser422. We further showed that miR-219-5p could mediate a decrease in the protein levels of tau-tubulin kinase 1 (TTBK1) and glycogen synthase kinase 3ß (GSK-3ß) by directly binding to their 3'-untranslated region, thereby promoting the phosphorylation of tau in SH-SY5Y Cells. Rescue experiments further revealed that the phosphorylation of tau-mediated by miR-219-5p was dependent on the inhibition of TTBK1 and GSK-3ß. Moreover, suppressing the expression of both TTBK1 and GSK-3ß using miR-219-5p remarkably rescued AD-like symptoms in amyloid precursor protein/presenilin 1 mice. Our findings indicate that the upregulation of TTBK1 and GSK-3ß mediated by the loss of miR-219-5p is a possible mechanism that contributes to tau phosphorylation and AD progression.

MiR-219-5p inhibits growth and metastasis of ovarian cancer cells by targeting HMGA2.

BACKGROUND: Accumulating studies have demonstrated that high-mobility group A2 (HMGA2), an oncofetal protein, plays a role in tumor development and progression. However, the molecular role of HMGA2 in ovarian carcinoma is yet to be established. MicroRNAs (miRNAs), a group of small noncoding RNAs, negatively regulate gene expression and their dysregulation has been implicated in tumorigenesis. The aim of this study was to investigate the potential involvement of a specific miRNA, miR-219-5p, in HMGA2-induced ovarian cancer. METHODS: The ovarian cancer cell line, SKOV3, was employed, and miR-219-5p and HMGA2 overexpression vectors constructed. The CCK-8 kit was used to determine cell proliferation and the Transwell® assay used to measure cell invasion and migration. RT-PCR and western blot analyses were applied to analyze the expression of miR-219-5p and HMGA2, and the luciferase reporter assay used to examine the interactions between miR-219-5p and HMGA2. Nude mice were employed to characterize in vivo tumor growth regulation. RESULTS: Expression of miR-219-5p led to suppression of proliferation, invasion and migration of the ovarian cancer cell line, SKOV3, by targeting HMGA2. The inhibitory effects of miR-219-5p were reversed upon overexpression of HMGA2. Data from the luciferase reporter assay showed that miR-219-5p downregulates HMGA2 via direct integration with its 3'-UTR. Consistent with in vitro findings, expression of miR-219-5p led to significant inhibition of tumor growth in vivo. CONCLUSION: Our results collectively suggest that miR-219-5p inhibits tumor growth and metastasis by targeting HMGA2.

MiR-219-5p inhibits growth and metastasis of ovarian cancer cells by targeting HMGA2

BACKGROUND: Accumulating studies have demonstrated that high-mobility group A2 (HMGA2), an oncofetal protein, plays a role in tumor development and progression. However, the molecular role of HMGA2 in ovarian carcinoma is yet to be established. MicroRNAs (miRNAs), a group of small noncoding RNAs, negatively regulate gene expression and their dysregulation has been implicated in tumorigenesis. The aim of this study was to investigate the potential involvement of a specific miRNA, miR-219-5p, in HMGA2-induced ovarian cancer. METHODS: The ovarian cancer cell line, SKOV3, was employed, and miR-219-5p and HMGA2 overexpression vectors constructed. The CCK-8 kit was used to determine cell proliferation and the Transwell® assay used to measure cell invasion and migration. RT-PCR and western blot analyses were applied to analyze the expression of miR-219-5p and HMGA2, and the luciferase reporter assay used to examine the interactions between miR-219-5p and HMGA2. Nude mice were employed to characterize in vivo tumor growth regulation. RESULTS: Expression of miR-219-5p led to suppression of proliferation, invasion and migration of the ovarian cancer cell line, SKOV3, by targeting HMGA2. The inhibitory effects of miR-219-5p were reversed upon overexpression of HMGA2. Data from the luciferase reporter assay showed that miR-219-5p downregulates HMGA2 via direct integration with its 3'-UTR. Consistent with in vitro findings, expression of miR-219-5p led to significant inhibition of tumor growth in vivo. CONCLUSION: Our results collectively suggest that miR-219-5p inhibits tumor growth and metastasis by targeting HMGA2.

MicroRNA-219-5p inhibits the proliferation, migration, and invasion of epithelial ovarian cancer cells by targeting the Twist/Wnt/ß-catenin signaling pathway.

MicroRNAs are emerging as critical regulators in various fundamental biological processes, including tumor progression. MicroRNA-219-5p (miR-219-5p) has been suggested as a novel tumor suppressing miRNA for many types of human cancers. However, the expression and functional significance of miR-219-5p in epithelial ovarian cancer remain poorly understood. In this study, we sought to explore the potential functions of miR-219-5p in epithelial ovarian cancer. Herein, we found that miR-219-5p levels were significantly decreased in epithelial ovarian cancer tissues and cell lines. Further experiments showed that overexpression of miR-219-5p inhibited epithelial ovarian cancer cell proliferation, migration, and invasion, and suppressed the Wnt/ß-catenin signaling pathway. By contrast, suppression of miR-219-5p exhibited the opposite effects. Twist was identified as a downstream target of miR-219-5p, and its expression was directly regulated by miR-219-5p. Restoration of Twist expression in miR-219-5p-overexpresing cells significantly reversed the antitumor effects of miR-219-5p. Taken together, our results revealed a tumor suppressive role for miR-219-5p in epithelial ovarian cancer that includes suppression of cell proliferation, migration, and invasion through downregulation of the Twist/Wnt/ß-catenin signaling pathway. Our study suggests that miR-219-5p may have potential applications in the diagnosis and treatment of epithelial ovarian cancer.

miR-219-5p suppresses the proliferation and invasion of colorectal cancer cells by targeting calcyphosin.

MicroRNAs (miRNAs) are small non-coding RNAs involved in an array of biological processes, and their dysregulation is associated with tumor development and progression. One such miRNA, miR-219-5p, is abnormally expressed in patients with colorectal cancer (CRC). In the present study, reverse transcription-quantitative polymerase chain reaction was performed to measure miR-219-5p expression in cells from both CRC tumors, and surrounding healthy tissue. MTT and invasion assays were used to determine the role of miR-219-5p in regulating CRC cell proliferation and invasion, respectively. A luciferase assay was then performed to assess the binding of miR-219-5p to the CAPS gene that encodes calcyphosin protein. The present study confirmed that miR-219-5p expression is significantly downregulated in CRC tissue. miR-219-5p knockdown promoted the growth of HCT-8 cells and increased the expression of calcyphosin protein (CAPS). On the other hand, overexpressing miR-219-5p inhibited HCT-8 cell growth and invasion, and downregulated CAPS expression. In addition, CAPS was identified as the functional downstream target of miR-219-5p by directly targeting its 3'-untranslated region. Therefore, miR-219-5p may function as a tumor suppressor by decreasing CAPS expression, and subsequently inhibit tumor proliferation and invasion. These results indicate that novel therapeutic strategies that increase miR-219-5p expression may be developed to treat CRC.

miR-219-5p inhibits proliferation and clonogenicity in chordoma cells and is associated with tumor recurrence.

Chordoma is a rare malignant bone tumor that is usually localized to the skull base, vertebral column and sacrum. The transcription factor brachyury, which is encoded by the T gene, has a critical role in the development and progression of chordoma, although the mechanisms underlying brachyury regulation remain unclear. The aim of the current study was to identify and characterize microRNAs (miRs) that regulate brachyury expression in chordoma. MicroRNAs that target brachyury were predicted using miRanda and TargetScan. Using reverse transcription-quantitative polymerase chain reaction, miR-219-5p was shown to be significantly downregulated in chordoma tissues and the U-CH2 chordoma cell lines. A dual-luciferase reporter assay was used to validate the inhibitory effect of miR-219-5p on brachyury mRNA expression. The expression level of brachyury was downregulated in U-CH2 cells following transfection with miR-219-5p mimics and upregulated following transfection with the miR-219-5p inhibitor. The effects of miR-219-5p on the proliferation and clonogenicity of chordoma cells were assessed using cell counting kit-8, EdU and clone formation assays. These in vitro results indicated that miR-219-5p may have an important role in regulating the cell proliferation and clonogenicity of human chordoma cells, potentially by targeting brachyury. Furthermore, the associations between the expression levels of miR-219-5p and various clinicopathological factors were analyzed, and miR-219-5p expression was shown to correlate with tumor extent and recurrence. These results suggested that miR-219-5p functions as a tumor suppressor in chordoma and, therefore, that miR-219-50 may be a potential target for therapeutic intervention.

MicroRNA-15b target Sall4 and diminish in vitro UCB-derived HSCs expansion.

Hematopoietic Stem Cells (HSCs) are cells that have the ability to self-renewal and differentiate into all of hematopoietic lineages. The lack of donors and unavailable efficient protocols for ex vivo expansion of HSCs, are obstacles in successful cell therapies. MicroRNAs (also refer as miRNAs or miRs) have significant roles in hematopoiesis; they can effect on HSCs expansion, maintaining undifferentiated state, self-renewal and differentiation. Recently attentions have been given to these small regulatory molecules to utilize them in order to expand HSCs. Using bioinformatics analysis we identified Sall4 as putative target of miR-15b and miR-219-5p. Relative expression levels of miRNAs and Sall4 were evaluated by qRT-PCR. Here we show 247-fold and 4.2-fold increasing Sall4 expression level compared to control group in CD34(+) cells nucleofected by anti-miR-15b and anti-miR-219-5p, respectively. These data showed that anti-miR-15b can promote clonogenic capacity of HSCs and also we found that miR-15b alone was able to increase the number of CD34(+)HSCs in vitro by more than 2 fold by targeting Sall4. Moreover, level of CD34 marker in HSCs nucleofected by anti-miR-15b increased more than 50 %. Our analysis showed no statistically difference in mRNA level of Sall4 after nucleofection of anti-miR-219-5p. Sall4 is a factor capable of enhancing HSC expansion significantly. We demonstrated that inhibition of miR-15b can enhance ex vivo expansion of UCB-derived HSCs and also expression of Sall4 allowed expansion and preserve self- renewal of CD34(+) HSCs.

MicroRNA-219-5p functions as a tumor suppressor partially by targeting platelet-derived growth factor receptor alpha in colorectal cancer.

Platelet-derived growth factor receptor (PDGFR) signaling pathway was involved in the progress of colorectal cancer (CRC). By using the bioinformatic system online, we found that PDGFRα is a potential target of miR-219-5p. However, the expression pattern and underlying mechanisms of miR-219-5p had not been elucidated in CRC. Herein, we first evaluated the expression of miR-219-5p in tumor tissues by real-time polymerase chain reaction. Next, we confirmed that PDGFRα is the target of miR-219-5p by using luciferase report. And then, we investigated the biological functions of miR-219-5p in vitro in cell proliferation and apoptosis as well as cell cycle by gain and loss of function strategies. Data shown that miR-219-5p is down-regulated in CRC tissues compared with the corresponding matched normal tissues. PDGFRα was a direct target of miR-219-5p. Overexpression of miR-219-5p could inhibit cell proliferation, promote cell apoptosis and induce cell cycle arrest at the G1 phase. Furthermore, miR-219-5p suppressed the activation of the phosphatidylinositol 3-kinase/Akt signaling pathway and downregulated G1 cell-cycle-related protein cyclin D1, cyclin-dependent kinase (CDK) 4, and CDK6. Taken together, our results demonstrate that miR-219-5p functions as a tumor suppressor partially by targeting PDGFRα in colorectal cancer.

MicroRNA-219-5p exerts tumor suppressor function by targeting ROBO1 in glioblastoma.

Previous studies have shown that miR-219-5p is dysregulated and exerts tumor-suppressive effects in cancer development and progression. However, the molecular function and mechanism of miR-219-5p in glioblastoma growth and invasion are still unclear. In the present study, we show that miR-219-5p was downregulated in a panel of glioma tissues with different grades and in all the human glioma cell lines examined. Ectopic expression of miR-219-5p inhibited proliferation and invasion and induced apoptosis in vitro, and xenograft formation in vivo. ROBO1 was found to be a direct target of miR-219-5p, and when overexpressed in miR-219-5p-expressing glioma cells, was able to restore proliferative and invasive ability. Finally, in vivo investigation confirmed that miR-219-5p was a tumor suppressor that regulated ROBO1 expression. Taken together, these studies demonstrate that miR-219-5p inhibited cancer cell growth and invasion by direct targeting ROBO1, implicating miR-219-5p as an attractive candidate for cancer therapy.

Integrated mRNA and micro RNA profiling reveals epigenetic mechanism of differential sensitivity of Jurkat T cells to AgNPs and Ag ions.

In our previous in vitro study of the toxicity on silver nanoparticles (AgNPs), we observed a dramatically higher sensitivity of Jurkat T cells to AgNPs than to Ag ions, and DNA damage and apoptosis were found to be involved in that toxicity. In this study, to understand underlying mechanism of different sensitivity of Jurket T cells to AgNPs and Ag ions, mRNA microarray and micro RNA microarray were concomitantly conducted on AgNPs and Ag ions exposed Jurkat T cells. Surprisingly only a small number of genes were differentially expressed by exposure to each of the silver (15 altered mRNA by AgNPs exposure, whereas 4 altered mRNA by Ag ions exposure, as determined 1.5-fold change as the cut-off value). miRNA microarray revealed that the expression of 63 miRNAs was altered by AgNPs exposure, whereas that of 32 miRNAs was altered by Ag ions exposure. An integrated analysis of mRNA and miRNA expression revealed that the expression of hsa-miR-219-5p, was negatively correlated with the expression of metallothionein 1F (MT1F) and tribbles homolog 3 (TRIB3), in cells exposed to AgNPs; whereas, the expression of hsa-miR-654-3p was negatively correlated with the expression of mRNA, endonuclease G-like 1 (EDGL1) in cells exposed to Ag ions. Network analysis were further conducted on mRNA-miRNA pairs, which revealed that miR-219-5p-MT1F and -TRIB3 pairs by AgNPs are being involved in various cellular processes, such as, oxidative stress, cell cycle and apoptosis, whereas, miR-654-3p and ENDOGL1 pair by Ag ions generated a much simpler network. The putative target genes of AgNPs-induced miR-504, miR-33 and miR-302 identified by Tarbase 6.0 are also found to be involved in DNA damage and apoptosis. These results collectively suggest that distinct epigenetic regulation may be an underlying mechanism of different sensitivity of Jurkat T cells to AgNPs and Ag ion. Further identification of putative target genes of DE miRNA by AgNPs and Ag ions may provide additional clues for the mechanism of differential toxicity. Overall results suggest that epigenetic mechanism is involved in toxicity of AgNPs and Ag ions in Jurkat T cells.