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Background/Purpose: Various microRNAs (miRs) have been found to be associated with the development of the precancerous condition of the oral cavity, oral submucous fibrosis (OSF). The expression of miR-29c is dysregulated in oral cancer, but its role in OSF has not been investigated. The purpose of the study is to investigate the functional role of miR-29c and its target in OSF. Methods: The expression levels of miR-29c in OSF tissues and fibrotic buccal mucosal fibroblasts (fBMFs) were assessed using next-generation sequencing and real-time Polymerase Chain Reaction (PCR) analysis. MiR-29c mimic and inhibitors were employed to examine its functional role of myofibroblast transdifferentiation. In addition, several myofibroblast phenotypes, such as collagen gel contraction and migration were tested, and a luciferase reporter assay was conducted to confirm the relationship between miR-29c and its predicted target, tropomyosin-1 (TPM1). Results: We observed that miR-29c expression was downregulated in fBMFs. fBMFs transfected with miR-29c mimics exhibited reduced migration ability and collagen gel contractility, whereas inhibition of miR-29c in normal BMFs induced the myofibroblast phenotypes. Results from the luciferase reporter assay showed that TPM1 was a direct target of miR-29c and the expression of TPM1 was suppressed in the fBMFs transfected with miR-29c mimics. Besides, we confirmed that the expression of miR-29c was indeed downregulated in OSF specimens. Conclusion: MiR-29c seems to exert an inhibitory effect on myofibroblast activation, such as collagen gel contractility and migration ability, via suppressing TPM1. These results suggested that approaches to upregulate miR-29c may be able to ameliorate the progression of OSF.

Introduction: GEO- and TCGA-based data analysis suggested the differential expression of miR-29c in pancreatic cancer. However, limited data are available on the downstream mechanistic actions of miR-29c, which may fuel the in vitro and in vivo studies of pancreatic cancer. Methods: The downstream target gene of miR-29c and the downstream ERK/MAPK pathway involved in pancreatic cancer were predicted by bioinformatics tools. Next, the expression of miR-29c and MAPK1 was determined in pancreatic cancer tissues and cells. After ectopic expression and depletion experiments in pancreatic cancer cells, oncogenic phenotypes of pancreatic cancer cells were tested by MTS assay, Transwell assay, and flow cytometry. Effects of miR-29c/MAPK1 on tumorigenic ability in vivo were evaluated in pancreatic cancer xenografts in nude mice. Results: Through differential analysis, five pancreatic cancer-related miRNAs (hsa-miR-29c, hsa-miR-107, hsa-miR-324-3p, hsa-miR-375, and hsa-miR-210) were screened out, among which miR-29c was selected as the key miRNA related to prognosis of pancreatic cancer patients. miR-29c could target and inhibit MAPK1 to suppress the activation of ERK/MAPK pathway. miR-29c was downregulated in pancreatic cancer, and its high expression was related to the good prognosis of pancreatic cancer patients. Both in vitro and in vivo experiments demonstrated that restoration of miR-29c inhibited oncogenic phenotypes of pancreatic cancer cells, as well as repressed tumorigenic ability of pancreatic cancer cells in nude mice. Conclusions: Taken together, we unveil a novel miR-29c/MAPK1/ERK/MAPK axis that suppresses pancreatic cancer both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Background/purpose: Various microRNAs (miRs) have been found to be associated with the development of the precancerous condition of the oral cavity, oral submucous fibrosis (OSF). The expression of miR-29c is dysregulated in oral cancer, but its role in OSF has not been investigated. The purpose of the study is to investigate the functional role of miR-29c and its target in OSF.Methods: The expression levels of miR-29c in OSF tissues and fibrotic buccal mucosal fibroblasts (fBMFs) were assessed using next-generation sequencing and real-time Polymerase Chain Reaction (PCR) analysis. MiR-29c mimic and inhibitors were employed to examine its functional role of myofibroblast transdifferentiation. In addition, several myofibroblast phenotypes, such as collagen gel contraction and migration were tested, and a luciferase reporter assay was conducted to confirm the relationship between miR-29c and its predicted target, tropomyosin-1 (TPM1).Results: We observed that miR-29c expression was downregulated in fBMFs. fBMFs transfected with miR-29c mimics exhibited reduced migration ability and collagen gel contractility, whereas inhibition of miR-29c in normal BMFs induced the myofibroblast phenotypes. Results from the luciferase reporter assay showed that TPM1 was a direct target of miR-29c and the expression of TPM1 was suppressed in the fBMFs transfected with miR-29c mimics. Besides, we confirmed that the expression of miR-29c was indeed downregulated in OSF specimens.Conclusion: MiR-29c seems to exert an inhibitory effect on myofibroblast activation, such as collagen gel contractility and migration ability, via suppressing TPM1. These results suggested that approaches to upregulate miR-29c may be able to ameliorate the progression of OSF. [ABSTRACT FROM AUTHOR]

Objective To observe the expression changes of microRNA-29c（miR-29c）and nuclear autoantigenic sperm protein（NASP）in non-small-cell lung cancer（NSCLC）A549 cells，and to explore their effects on the prolifera⁃ tion，migration，invasion and apoptosis of A549 cells and to verify the targeting relationship between them. Methods A549 cells and normal human pulmonary epithelial cells HBE were selected. The miR-29c mRNA and NASP mRNA in the above cells were detected by qRT-PCR，and NASP protein was detected by Western blotting. We divided A549 cells into the miR-NC group（transfected with miR-29c negative control sequence），miR-29c group（transfected with miR-9c overex⁃ pression sequence)，and si-NC group（transfected with NASP silent negative control sequence), si-NASP group（transfect⁃ ed with NASP silence sequence)，miR-29c+NC group（co-transfected with miR-29c overexpression sequence and NASP overexpression negative control sequence)，and miR-29c+ NASP group（co-transfection with miR-29coverexpression and NASP overexpression sequence). CCK-8 was used to detect cell proliferation in each group；flow cytometry was used to calculate the apoptosis rate of each group；Transwell assay was used to detect cell migration and invasion abilities of each group. The dual-luciferase reporter gene detection test was used to identify their targeting relationship between miR-29c and NASP. Results Compared with HBE cells，the expression of miR-29c decreased，and the expression of NASP increased in A549 cells（both P<0. 05）. Compared with the miR-NC group, the proliferative activity of A549 cells was weaker，the apoptosis rate increased，and the migration and invasion abilities decreased in the miR-29c group（all P<0. 05）. Compared with the si-NC group，the proliferative activity of A549 cells in the si-NASP group was weaker，the apoptosis rate increased，and the migration and invasion abilities decreased（all P<0. 05）. Compared with the miR-29c+NC group， the miR-29c+NASP group had higher A549 cell proliferation ability，lower apoptosis rate，and higher migration and inva⁃ sion abilities（all P<0. 05）. The dual-luciferase experiment confirmed that there was a targeting relationship between miR29c and NASP. Conclusions In NSCLC A549 cells，the expression of miR-29c increases and expression of NASP decreases. MiR-29c inhibits the proliferation，migration and invasion of A549 cells，and promotes their apoptosis, while NASP promotes their proliferation，migration and invasion，and inhibits the apoptosis；overexpression of NASP can reverse the inhibition of miR-29c on proliferation and migration and induction of apotosis of A549 cells；miR-29c has a targeting relationship with NASP. [ABSTRACT FROM AUTHOR]

As a single cardiac malformation, ventricular septal defect (VSD) is the most common form of congenital heart disease. However, the precise molecular mechanisms underlying VSD are not completely understood. Numerous microRNAs (miRs/miRNAs) are associated with ventricular septal defects. miR-29c inhibits the proliferation and promotes the apoptosis and differentiation of P19 embryonal carcinoma cells, possibly via suppressing Wnt4 signaling. However, to the best of our knowledge, no in vivo studies have been published to determine whether overexpression of miR-29c leads to developmental abnormalities. The present study was designed to observe the effect of miRNA-29c on cardiac development and its possible mechanism in vivo. Zebrafish embryos were microinjected with different doses (1, 1.6 and 2 µmol) miR-29c mimics or negative controls, and hatchability, mortality and cardiac malformation were subsequently observed. The results showed that in zebrafish embryos, miR-29c overexpression attenuated heart development in a dose-dependent manner, manifested by heart rate slowdown, pericardial edema and heart looping disorder. Further experiments showed that overexpression of miR-29c was associated with the Wnt4/β-catenin signaling pathway to regulate zebrafish embryonic heart development. In conclusion, the present results demonstrated that miR-29c regulated the lateral development and cardiac circulation of zebrafish embryo by targeting Wnt4. [ABSTRACT FROM AUTHOR]

A significant decrease in the expression of spinal microRNA-29c (miR-29c), which is responsible for the regulation of oxytocin receptor (OXTR) expression, was observed in nerve injury pain during childbirth. The present study investigates whether spinal miR-29c could be a potential target for the treatment of pain, via the oxytocin (OT)-γ-aminobutyric acid (GABA) pathway. A spared nerve injury (SNI) rat model was established to induce neuropathic pain, simulating hyperalgesia. Spinal neurons were treated with OT to mimic the hormonal changes in the central nervous system after delivery. A change in the neuronal miniature inhibitory postsynaptic currents (mIPSCs) was observed in neurons, following the silencing of miR-29c or OT treatment with or without OXTR antagonist. The Von-Frey apparatus was used to measure the animal behaviors. Molecular biological experiments and electrophysical recordings in vivo and in vitro were performed to reveal the potential analgesic mechanisms. miR-29c was significantly downregulated (more than 8-fold) in the spinal dorsal horn of delivery+SNI rats compared with the SNI rats. The silencing of miR-29c resulted in increased pain threshold in SNI rats. Bioinformatics analysis indicated that OXTR was a potential target gene of miR-29c. The delivery+SNI rats presented with higher levels of OT in the cerebrospinal fluid compared with SNI rats, which indicated that the OT signaling pathway may participate in pain relief response. The increased expression of OXTR and GABA in delivery+SNI rats were observed in the miR-29c-silenced SNI rat model, suggesting that the silencing of miR-29c can mediate pain relief by enhancing the OT-GABA pathway. In addition, an electrophysiology assay was performed to assess the mIPSCs in neurons. The silencing of miR-29c in neurons increased the frequency and amplitude of mIPSCs but there was no influence on the decay time, which suggested that the spinal inhibitory neurons became more active, subsequently reducing the feeling of pain. The inhibition of OXTR reversed the enhanced inhibitory postsynaptic currents, indicating a crucial role for OXTR in the miR-29c-associated pain regulation. Taken together, the results of the present study suggested that spinal oxytocinergic inhibitory control plays an important role in pain relief in the neuropathic pain rat model undergoing vaginal delivery. Silencing spinal miR-29c may be a potential target for pain relief through the OT-GABA pathway. [ABSTRACT FROM AUTHOR]

Liver cancer is one of the most prevalent human tumors in the world. Despite recent advances regarding the understanding of the molecular basis of liver cancer and the introduction of novel chemotherapeutic approaches, liver cancer remains associated with a poor prognosis. Sirtuin 1 (SIRT1) was identified to be abnormally upregulated in liver cancer. Dysregulation of microRNAs (miRs/miRNAs) is associated with a variety of types of cancer, and miRNAs may also serve a role in tumorigenesis and progression. The present study demonstrated that following the selection of the cisplatin chemoresistant HepG2 cell line, miR-29c is downregulated using reverse transcription-quantitative polymerase chain reaction. Furthermore, overexpression of miR-29c in cisplatin- resistant cancer cells was demonstrated to inhibit tumor cell proliferation and to promote apoptosis in vitro and in vivo, as well as restoring cisplatin chemosensitivity by using a cell counting assay, colony formation assay, Annexin V-fluorescein isothocyanate/propidium iodide apoptosis analysis, terminal deoxynucleotidyl transferase dUTP nick end labeling and xenograft tumors in nude mice. Mechanistically, according to bioinformatics analysis and a luciferase assay, miR-29c may directly target SIRT1 mRNA and repress SIRT1 expression, which is positively associated with the chemoresistance of liver cancer and may ultimately provide a novel therapeutic method. [ABSTRACT FROM AUTHOR]

Non-small cell lung cancer (NSCLC) is a primary sub-type of lung cancer with a high incidence rate and poor prognosis. The primary therapeutic treatment for NSCLC is chemotherapy, which is considered to be ineffective and excessively toxic. Novel therapeutic methods, particularly molecular targeted therapy, have attracted considerable attention. MicroRNAs (miRs) are reported to be potential biomarkers and targeted agents with roles in various types of tumors. Herein, the present study presented the observation of aberrant low expression of miR‑29c and associated overexpression of vascular endothelial growth factor A (VEGFA) in NSCLC tumor tissues. The effects of miR‑29c upon NSCLC tumor progression, including cell proliferation and cellular apoptosis, were investigated. The possible regulatory mechanism of action of miR‑29c on its direct target VEGFA and the phosphatidylinositol 3‑kinase (PI3K)/RAC‑α serine/threonine‑protein kinase (Akt) signaling pathway was examined using multiple methods, including reverse transcription-quantitative polymerase chain reaction analysis, dual luciferase assay and western blot analysis. The results demonstrated that miR‑29c expression was downregulated in NSCLC tumor tissues compared with normal tissues. A marked negative correlation in the expression of miR‑29c and VEGFA was observed in clinical NSCLC tissues and cultured NSCLC cells. Overexpression of miR‑29c may inhibit cell proliferation and accelerate the cellular apoptosis rate of NSCLC tumor cells. Furthermore, the overexpression of miR‑29c was demonstrated to be able to downregulate the expression levels of VEGFA and PI3K/Akt signaling pathway‑associated proteins. The results of the present study suggested that miR‑29c might regulate NSCLC tumor progression by targeting VEGFA. [ABSTRACT FROM AUTHOR]

In our previous study, the upregulation of microRNA (miR)-29c was identified in the mother of a fetus with a congenital heart defect. However, the functional and regulatory mechanisms of miR-29c in the development of the heart remain to be elucidated. In the present study, the role and mechanism of miR-29c inhibition in heart development were investigated in an embryonic carcinoma cell model. Inhibition of miR-29c promoted proliferation, and suppressed the apoptosis and differentiation of P19 cells. It was also demonstrated that Wingless-related MMTV integration site 4 (Wnt4) was a target of miR-29c, determined using bioinformatic analysis combined with luciferase assays. The inhibition of miR-29c stimulated the WNT4/β-catenin pathway, promoting proliferation of the P19 cells, but suppressing their differentiation into cardiomyocytes. Furthermore, the inhibition of miR-29c promoted the expression of B cell lymphoma-2 and inhibited cell apoptosis. These results demonstrate the significance of miR-29c in the process of cardiac development and suggest that miR-29c dysregulation may be associated with the occurrence of CHD. Thus, miR-29c may have therapeutic potential in the future. [ABSTRACT FROM AUTHOR]

Leukemia inhibitory factory (LIF), as a member of the IL-6 family, has been reported to ameliorate myocardial fibrosis and myocardial cell death. The purpose of the present study was to investigate the effect of LIF on renal fibrosis and its underlying mechanism. Our results showed, first, that LIF inhibited collagen type 1 and collagen type 3 expression induced by ANG II in NRK-49F (rat kidney fibroblast) cells and in mice with unilateral ureteral obstruction. Second, LIF induced Stat3 Tyr705 phosphorylation and inhibited Stat3 Tyr705 and Ser727 phosphorylation induced by ANG II in NRK-49F cells. Third, LIF exerted an antirenal fibrosis effect mainly through activation of Stat3 Tyr705 phosphorylation in NRK-49F cells. These effects of LIF were not observed in Stat3-/- cells. Finally, LIF-Stat3 upregulated microRNA-29c expression, and the latter downregulated collagen type 1 and collagen type 3 expression in NRK-49F cells and in mice with unilateral ureteral obstruction. In conclusion, LIF played a role in antirenal fibrosis by competitively activating Stat3 Tyr705 phosphorylation, which upregulated microRNA-29c to suppress collagen expression. [ABSTRACT FROM AUTHOR]

Abstract: Specificity protein 1 (Sp1), a ubiquitously expressed transcription factor, plays a potential pathogenic role for fibrotic disease in many organs by regulating the expression of several fibrosis-related genes, however, its role in kidney fibrosis and the mechanisms regulating its expression remain incompletely clarified. Here, we found that Sp1 was markedly induced and closely correlated with interstitial type I collagen accumulation in kidney tubular epithelia from obstructive nephropathy. In vitro, both Sp1 and type I collagen expression were up-regulated in TGF-β1-treated kidney tubular epithelial cells (NRK-52E), whereas knockdown of Sp1 largely abolished TGF-β1-induced type I collagen production, suggesting that Sp1 induction is partially responsible for type I collagen expression. In addition, we found that miR-29c expression was remarkably reduced in either the tubular epithelial cells from kidney with UUO nephropathy or TGF-β1-treated NRK-52E cells. Knockdown of miR-29c could sufficiently induce Sp1 and type I collagen expression, whereas ectopic expression of miR-29c largely abolished their expression stimulated by TGF-β1 in NRK-52E cells. Furthermore, knockdown of Sp1 effectively hindered type I collagen induction stimulated by miR-29c down-regulation. Collectively, this study demonstrates that Sp1 acts as an essential mediator for miR-29c in regulating type I collagen production in tubular epithelial cells, which may provide a novel mechanistic insight about miR-29c in renal fibrosis. [Copyright &y& Elsevier]

Abstract: This study was aimed to investigate the potential role of microRNA-29c (miR-29c) in regulating the sensitivities of nasopharyngeal carcinoma (NPC) to ionizing radiation (IR) and cisplatin. Low expression of miR-29c was positively associated with therapeutic resistance in 159 NPC cases. Our further in vitro and in vivo studies illustrated ectopic restoration of miR-29c substantially enhanced the sensitivity of NPC cells to IR and cisplatin treatment by promoting apoptosis. Furthermore, we detected miR-29c repressed expression of anti-apoptotic factors, Mcl-1 and Bcl-2 in NPC tissues and cell lines. These data indicate miR-29c might serve as a potential therapeutic sensitizer in NPC treatment. [Copyright &y& Elsevier]

Successful repair and renewal of alveolar epithelial cells (AECs) are critical in prohibiting the accumulation of myofibroblasts in pulmonary fibrogenesis. MicroRNAs (miRNAs) are multifocal regulators involved in lung injury and repair. However, the contribution of miRNAs to AEC2 renewal and apoptosis is incompletely understood. We report that miRNA-29c (miR-29c) expression is lower in AEC2s of individuals with idiopathic pulmonary fibrosis than in healthy lungs. Epithelial cells overexpressing miR-29c show higher proliferative rates and viability. miR-29c protects epithelial cells from apoptosis by targeting forkhead box O3a (Foxo3a). Both overexpression of miR-29c conventionally and AEC2s specifically lead to less fibrosis and better recovery in vivo. Furthermore, deficiency of miR-29c in AEC2s results in higher apoptosis and reduced epithelial renewal. Interestingly, a gene network including a subset of apoptotic genes was coregulated by both Toll-like receptor 4 and miR-29c. Taken together, miR-29c maintains epithelial integrity and promotes recovery from lung injury, thereby attenuating lung fibrosis in mice.

Aim: To determine the role of microRNA (miRNA)-29a and miRNA-29c in the regulation of apoptosis in early rat diabetic cataract formation., Methods: Streptozotocin (STZ)-induced diabetic Sprague-Dawley (SD) rats were used in the study. The expression level of miRNA-29a, miRNA-29c, and BCL2-modifying factor (BMF) in lens epithelial cells (LECs) samples were measured using quantitative real-time polymerase chain reaction. Prediction algorithms of miRanda, TargetScan 6.2, and mirRDB to perform a miRNA gene network analysis were used for the potential miRNA-29a and miRNA-29c targets., Results: The miRNA-29a and miRNA-29c expression levels were all significantly lower in the control group compared to the 2 and 4wk diabetic samples ( P <0.01). The network analysis indicated that one miRNA-29a and miRNA-29c targets was BMF. There was significantly higher expression of BMF mRNA compared to the normal controls ( P <0.01)., Conclusion: Apoptosis occurs in rat LECs following high blood glucose exposure. It is likely that apoptosis during diabetic cataract formation involves the decreased expression of miRNA-29a and miRNA-29c and the increased expression of BMF.