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Persistent inflammation in the secondary spinal cord injury (SCI) is an important reason for the failure of nerve repair, which is partly due to the continuous activation of local M1-like macrophage/microglia. It is reported that extracellular trap (ET) has been a new way of cell death, which can be released by macrophages and named macrophage extracellular trap (Met). Furthermore, it exists widely in the pathophysiological process of many diseases, but it has been rarely studied in the field of SCI. In this study, we constructed a spinal cord contusion model and assessed the function outcome of SCI rats. We used immunofluorescence, flow cytometry, and transmission electron microscope (TEM) to demonstrate the existence of Mets. Besides, some related experiments had also been employed to explore the relationship between Mets and M1 polarization of macrophage/microglia. We also performed Co-IP and Western blotting to reveal a new extracellular proinflammatory signal pathway. Finally, we made a linear regression analysis between the concentrations of specific markers of Mets in human serum and ASIA scores. Briefly, our results suggested that macrophages infiltrated in SCI area could induce macrophage/microglia to differentiate into M1-like cells by releasing Mets, which may be achieved partly through LL37-P2X37-NF-κB signal pathway. However, limiting Mets could effectively inhibit M1 polarization and promote function recovery. In addition, the concentrations of Met related proteins in human serum showed high correlation with ASIA scores and could be applied to reflect the severity of SCI. In conclusion, Mets may be a new target for SCI therapy and a promising index for SCI assessment.

Introduction: Olfactory ensheathing cells (OECs) are important transplantable cells for the treatment of spinal cord injury. However, information on the mechanism of OEC-derived extracellular vesicles (EVs) in nerve repair is scarce. Methods: We cultured OECs and extracted the OEC-derived EVs, which were identified using a transmission electron microscope, nanoparticle flow cytometry, and western blotting. High throughput RNA sequencing of OECs and OEC-EVs was performed, and the differentially expressed microRNAs (miRNAs) (DERs) were analyzed by bioinformatics. The target genes of DERs were identified using miRWalk, miRDB, miRTarBase, and TargetScan databases. Gene ontology and KEGG mapper tools were used to analyze the predicted target genes. Subsequently, the STRING database and Cytoscape software platform were used to analyze and construct miRNA target genes' protein-protein interaction (PPI) network. Results: Overall, 206 miRNAs (105 upregulated and 101 downregulated) were differentially expressed in OEC-EVs (P < 0.05;|log2 (fold change)|>2). Six DERs (rno-miR-7a-5p, rno-miR-143-3p, rno-miR-182, rno-miR-214-3p, rno-miR-434-5p, rno-miR-543-3p) were significantly up-regulated , and a total of 974 miRNAs target genes were obtained. The target genes were mainly involved in biological processes such as regulation of cell size, positive regulation of cellular catabolic process and small GTPase-mediated signal transduction; positive regulation of genes involved in cellular components such as growth cone, site of polarized growth, and distal axon; and molecular functions such as small GTPase binding and Ras GTPase binding. In pathway analysis, target genes regulated by six DERs were mainly enriched in axon guidance, endocytosis, and Ras and cGMP-dependent protein kinase G signaling pathways. Finally, 20 hub genes were identified via the PPI network. Conclusion: Our study provides a theoretical basis for treating nerve repair by OEC-derived EVs.

Lithium is associated with oxidative stress and apoptosis, but the mechanism by which lithium protects against spinal cord injury remains poorly understood. In this study, we found that intraperitoneal administration of lithium chloride (LiCl) in a rat model of spinal cord injury alleviated pathological spinal cord injury and inhibited expression of tumor necrosis factor α, interleukin-6, and interleukin 1 β. Lithium inhibited pyroptosis and reduced inflammation by inhibiting Caspase-1 expression, reducing the oxidative stress response, and inhibiting activation of the Nod-like receptor protein 3 inflammasome. We also investigated the neuroprotective effects of lithium intervention on oxygen/glucose-deprived PC12 cells. We found that lithium reduced inflammation, oxidative damage, apoptosis, and necrosis and up-regulated nuclear factor E2-related factor 2 (Nrf2) and heme oxygenase-1 in PC12 cells. All-trans retinoic acid, an Nrf2 inhibitor, reversed the effects of lithium. These results suggest that lithium exerts anti-inflammatory, anti-oxidant, and anti-pyroptotic effects through the Nrf2/heme oxygenase-1 pathway to promote recovery after spinal cord injury. This study was approved by the Animal Ethics Committee of Xi'an Jiaotong University (approval No. 2018-2053) on October 23, 2018.

Spinal cord injury (SCI) is a major cause of paralysis, disability and even death in severe cases. Lithium has neuroprotective effects on SCI, while the underlying mechanisms remain obscure. In the present study, we established a SCI rat model, which subsequently received lithium treatment. Results displayed that lithium treatment improved the locomotor function recovery and reduced apoptosis by increasing anti-apoptotic molecule expression and decreasing pro-apoptotic factor expression in SCI rats. Furthermore, lithium treatment alleviated the inflammatory response by inactivating the nuclear factor-kappa B (NF-κB) pathway and inhibited the expression of lncRNA brain-derived neurotrophic factor antisense (BDNF-AS) in SCI rats. Subsequent researches indicated that miR-9-5p was targeted and regulated by BDNF-AS. Lithium treatment rescued the upregulation of BDNF-AS expression and downregulation of miR-9-5p expression induced by H2O2 in SH-SY5Y cells. BDNF-AS overexpression or miR-9-5p interference attenuated the anti-apoptotic and anti-inflammatory effects of lithium chloride in SH-SY5Y cells that was damaged by H2O2 induction, revealing that lithium might act through the BDNF-AS/miR-9-5p axis. In vivo studies showed that the injection of BDNF-AS adenovirus vector or miR-9-5p inhibitor reversed the effects of lithium on the histologic morphology of spinal cord, motor function, inflammatory reaction and apoptosis in SCI rats, which was consistent with the results of in vitro studies. In conclusion, our data demonstrated that lithium reduced SCI-induced apoptosis and inflammation in rats via the BDNF-AS/miR-9-5p axis.

Vitamin D3 has been demonstrated to suppress the development and progression of liver cancer, but the mechanism is unclear. The effects of vitamin D3 and microRNA (miR)-15a-5p on liver cancer cells were investigated in the present study using MTT and colony formation assays, flow cytometry, western blotting and reverse transcription-quantitative PCR. A dual-luciferase reporter assay was performed to determine whether E2F transcription factor 3 (E2F3) was a target of miR-15a-5p. The effects of silencing the E2F3 gene expression in liver cancer cells were investigated using a small interfering RNA. Vitamin D3 suppressed liver cancer cell proliferation, induced apoptosis and increased miR-15a-5p expression. Treatment with the miR-15a-5p mimics significantly suppressed liver cancer cell proliferation compared with that of the controls. Bioinformatics analysis and a dual-luciferase reporter assay demonstrated that E2F3 was a target of miR-15a-5p and that silencing E2F3 inhibited liver cancer cell proliferation. Therefore, Vitamin D3 suppressed cell proliferation by miR-15a-5p-mediated silencing of E2F3 gene expression. These findings suggested a role for vitamin D3 and E2F3 targeting as potential novel liver cancer therapies.

EGR1 regulates the expression of its downstream target genes and may exert different biological effects in different tumours. We found that the expression of EGR1 was increased in gastric cancer (GC), and silencing the expression of EGR1 promoted the apoptosis of GC cells. Moreover, overexpression of EGR1 repressed the apoptosis of GC cells. Bioinformatics analysis showed that EGR1 had binding sites at the upstream promoter region of miR‐195; ChIP assays were applied to determine EGR1 occupancy of the miR‐195 promoter. The RT‐PCR results showed that EGR1 suppressed the expression of miR‐195. The mechanism by which EGR1 acts as a transcriptional repressor is still unclear. Bioinformatics analysis showed that EGR1 may interact with DNMT3L. We confirmed that EGR1 and DNMT3L formed a complex, and EGR1 was an important player in the transcriptional control of miR‐195. Overexpression of miR‐195 inhibited proliferation and promoted apoptosis in GC cells. We found a well‐matched miR‐195 binding site at the AKT3 3′‐UTR. Double luciferase reporter assays showed that AKT3 was a target of miR‐195, and silencing AKT3 repressed cell proliferation and promoted apoptosis. Our results indicated EGR1 may interact with DNMT3L to inhibit the miR‐195‐AKT3 axis and regulate the GC cell apoptosis.

MicroRNAs (miRNAs) function as gene expression switches, and participate in diverse pathophysiological processes of spinal cord injury (SCI). Olfactory ensheathing cells (OECs) can alleviate pathological injury and facilitate functional recovery after SCI. However, the mechanisms by which OECs restore function are not well understood. This study aims to determine whether silencing miR-199a-5p would enhance the beneficial effects of the OECs. In this study, we measured miR-199a-5p levels in rat spinal cords with and without injury, with and without OEC transplants. Then, we transfected OECs with the sh-miR-199a-5p lentiviral vector to reduce miR-199a-5p expression and determined the effects of these OECs in SCI rats by Basso–Beattie–Bresnahan (BBB) locomotor scores, diffusion tensor imaging (DTI), and histological methods. We used western blotting to measure protein levels of Slit1, Robo2, and srGAP2. Finally, we used the dual-luciferase reporter assay to assess the relationship between miR-199-5p and Slit1, Robo2, and srGAP2 expression. We found that SCI significantly increased miR-199a-5p levels ( P < 0.05), and OEC transplants significantly reduced miR-199a-5p expression ( P < 0.05). Knockdown of miR-199a-5p in OECs had a better therapeutic effect on SCI rats, indicated by higher BBB scores and fractional anisotropy values on DTI, as well as histological findings. Reducing miR-199a-5p levels in transplanted OECs markedly increased spinal cord protein levels of Slit1, Robo2, and srGAP2. Our results demonstrated that transplantation of sh-miR-199a-5p-modified OECs promoted functional recovery in SCI rats, suggesting that miR-199a-5p knockdown was more beneficial to the therapeutic effects of OEC transplants. These findings provided new insights into miRNAs-mediated therapeutic mechanisms of OECs, which helps us to develop therapeutic strategies based on miRNAs and optimize cell therapy for SCI.

Gastric cancer (GC), one of the most common malignant tumors and the second most common leading cause of cancer-related death worldwide, is a biologically heterogeneous disease accompanied by various genetic and epigenetic alterations. However, the molecular mechanisms underlying this disease are complex and not completely understood. Increasing studies have shown that aberrant microRNA (miRNA) expression is associated with GC tumorigenesis and growth. MiR-1297 has been confirmed to be a cancer suppressor in diverse tumors in humans. However, to date, the function and mechanism of miR-1297 in GC have not been determined. Here, we found that the expression of miR-1297 was significantly reduced in GC tissues or GC cell lines compared with paracarcinoma normal tissue or normal cell lines. Exogenic overexpression of miR-1297 in GC cell lines can inhibit cell proliferation and colony formation and induce apoptosis, and inhibition of miR-1297 in GC cell lines can promote cell proliferation and colony formation, and reduce apoptosis in vitro. We further confirmed that miR-1297 acted as a tumor suppressor through targeting cell division control protein 6 (CDC6) in GC. Moreover, the inverse relationship between miR-1297 and CDC6 was verified in GC cell lines. Our results indicated that miR-1297 is a potent tumor suppressor in GC, and its antiproliferative and gene-regulatory effects are, in part, mediated through its downstream target gene, CDC6. These findings implied that miR-1297 might be used as a novel therapeutic target of GC.

// Dongdong Tong 1, 2 , Lingyu Zhao 1, 2 , Kang He 1, 2, 3 , Hongfei Sun 1, 2 , Donghui Cai 1, 2 , Lei Ni 1 , Ruifang Sun 4 , Su’e Chang 5 , Tusheng Song 1, 2 , Chen Huang 1, 2 1 Department of Cell Biology and Genetics, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Shaanxi, P. R. China 2 Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education of China, Shaanxi, P. R. China 3 Department of Periodontology, Stomatology Hospital of Xi’an Jiaotong University College of Medicine, Xi’an, Shaanxi, P. R. China 4 Department of pathology, College of Medicine, Xi’an Jiaotong University, Xi’an, Shaanxi, P. R. China 5 Department of Orthopaedics, the Second Affiliated Hospital, School of Medicine, Xi’an Jiaotong University, Xi’an, Shaanxi, P. R. China Correspondence to: Chen Huang, email: hchen@mail.xjtu.edu.cn Keywords: gastric cancer, MECP2, miR-338, BMI1, proliferation Received: October 19, 2015 Accepted: March 31, 2016 Published: May 06, 2016 ABSTRACT The methyl-CpG-binding protein 2 (MECP2), a transcriptional suppressor, is involved in gene regulation by binding to methylated promoters. We found that MECP2 is overexpressed in gastric cancer (GC), and that Mecp2 knockdown affects the growth of GC cells both in vitro and in vivo . MECP2 can directly bind to the methylated-CpG island of miR-338 promoter and suppress the expression of two mature microRNAs, namely, miR-338-3p and miR-338-5p. Furthermore, miR-338-5p can suppress GC cell growth by targeting BMI1 (B lymphoma Mo-MLV insertion region 1 homolog). We additionally found that decreased miR-338-5p expression in GC tissues, relative to normal tissues, was significantly negatively correlated with increased BMI1 expression. Silencing MECP2 can indirectly lead to reduced expression of P-REX2, which has been identified as the miR-338-3p target, as well as BMI1 and increasing expression of P16 or P21 both in vitro and in vivo . Altogether, our results indicate that MECP2 promote the proliferation of GC cells via miR-338 (miR-338-3p and miR-338-5p)-mediated antitumor and gene regulatory effect.

Vitamin D3 is known to have anticancer actions by affecting tumorigenesis including the cell cycle and cell apoptosis in gastric cancer (GC) cells; the genes including microRNAs (miRNAs) regulated by vitamin D3 signaling remain discovered. miR-99b-3p, the tumor suppressor gene, is not only decreased in GC tissues, but is also induced by vitamin D3 through the vitamin D receptor (VDR) binding on the promoter domain of miR-99b. Further study indicates that miR-99b-3p inhibits cell viability and induces cell arrest in the S-phase in GC cells, the direct target gene of miR-99b-3p is verified to be HoxD3, which is also overexpressed in GC cell lines. Overall, our results show that miR-99b-3p mediates the antiproliferative of vitamin D3 in GC cells and might hold promise for prognosis and therapeutic strategies for GC treatment.

MicroRNAs (miRNAs) are a class of small, non‑coding, endogenous RNAs that are important in tumor cell biological processes as they regulate gene expression. miR-195 has been demonstrated to be a tumor repressor in numerous types of human cancer. However, the mechanism by which miR‑195 suppresses tumor development remains to be elucidated. The aim of this study was to investigate the effect of miR-195 on the biological functions of HepG2 hepatocellular carcinoma (HCC) cells and identify the association between miR-195 and Wnt3a in HCC. miR-195 mRNA expression levels in HCC tissues and cell lines were measured by reverse transcription polymerase chain reaction analysis. miR-195 function was measured with cell proliferation, cell cycle and apoptosis assays following transfection with miR‑195 and anti‑miR‑195 sequences, and the respective controls. Luciferase reporter assay was used to determine whether Wnt3a was a target of miR-195. In addition, Wnt3a expression levels were determined in HCC cells using western blot analysis. The miR-195 expression levels were found to be reduced in HCC tissues and cell lines. miR-195 overexpression resulted in a reduction in cell proliferation. In addition, the overexpression of miR-195 in HCC cells induced G1 phase cell cycle arrest and promoted apoptosis. Furthermore, Wnt3a was demonstrated to be directly targeted by miR-195. These findings suggest that miR-195 is key in regulating cell proliferation, cell cycle and apoptosis through targeting Wnt3a. In addition, overexpression of miR-195 may be a potential therapeutic strategy in the treatment of HCC.

// Ling Gao 1,2 , Xiaolong Wang 1 , Xiaofei Wang 2 , Linmei Zhang 1 , Cui Qiang 1 , Su’e Chang 2 , Wenhao Ren 1 , Shaoming Li 1 , Yang Yang 2 , Dongdong Tong 2 , Cheng Chen 1 , Zongfang Li 3 , Tusheng Song 2 , Keqian Zhi 1 , Chen Huang 2 1 Department of Oral Maxillofacial Surgery, Stomatology Hospital of Xi’an Jiaotong University College of Medicine, Xi’an, Shaanxi, P. R. China 2 Key Laboratory of Environment and Genes Related to Diseases, College of Medicine, Xi’an Jiaotong University, Xi’an, Shaanxi, P. R. China 3 Department of General Surgery, the Second Affiliated Hospital, School of Medicine, Xi’an Jiaotong University, Xi’an, Shaanxi, P. R. China Correspondence: Chen Huang, email: // Keqian Zhi, email: // Keywords : oral squamous cell carcinoma; IGF-1R; IRS-2; let-7b; proliferation Received : January 8, 2014 Accepted : March 19, 2014 Published : March 21, 2014 Abstract Insulin-like growth factor (IGF) signaling is involved in oral squamous cell carcinoma (OSCC), but IGF-1 receptor (IGF-1R)-mediated intricate regulatory networks among molecular interactions and signalling path ways in OSCC remain unclear. Here, we found that overexpression of IGF-1R and insulin receptor substrate-2 (IRS-2) was negatively associated with histological differentiation. IGF signaling stimulated OSCC cell growth. Conversely, overexpression of let-7b inhibited proliferation and colony formation and triggered S/G2 cell cycle arrest by targeting IGF-1R and IRS-2 through the Akt pathway. Also, the inverse relationship between expression of let-7b and IGF-1R/IRS-2 was confirmed in OSCC tumor xenografts and clinical specimens. Furthermore, by activating ERK1/2, IGF-1R transcriptionally upregulated IRS-2. Our results indicate that let-7b/IGF-1R-mediated crosstalk between IRS-2/Akt and MAPK is involved in OSCC and is a potential therapeutic target for therapy.

Background: MicroRNAs have been reported to play roles as oncogenes or tumor suppressor genes in human cancers. However, the expression levels of miR-145 in oral squamous cell carcinoma (OSCC) are unclear. The purpose of this study was to investigate the status of miR-145 expression in OSCC and determine its clinical significance. Patients and Methods: We examined miR-145 levels in 62 OSCC tissue samples and cell lines by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). The relationship between miR-145 expression and clinicopathologic factors of OSCC patients was analyzed. Results: The proportion of miR-145 low expression was 82.26% (51/62) among the 62 OSCC patients, and expression levels of miR-145 in OSCC tissue samples and cell lines were significantly lower than in non-tumor controls. miR-145 expression levels were not significantly associated with age (p = 0.607), sex (p = 0.213), location (p = 0.952), histology (p = 0.603), pT stage (p = 0.305), pTNM stage (p = 0.471), and lymphatic metastasis (p = 1.000). Conclusion: miR-145 may be involved in the early tumorigenesis of oral squamous cells, and might be a potential biomarker in the early diagnosis of OSCC.

MiR-302b is a member of miR-302-367 cluster. The miR-302-367 cluster played important roles in maintaining pluripotency in human embryonic stem cells (hESCs) and has been proved to be capable of suppressing cell growth in several types of cancer cell lines including Hepatocellular Carcinoma (HCC) Cell lines. However, the role that miR-302b plays in the 5-Fluorouracil (5-FU) sensitivity of HCC has not been known. This study showed that miR-302b could enhance the sensitivity to 5-FU in HCC cell lines and verified its two putative targeted genes responsible for its 5-FU sensitivity.

Dysregulation of microRNAs (miRNAs) has been associated with carcinogenesis in oral squamous cell carcinoma (OSCC). In the present study, we investigated the expression and function of miR-99b-3p in human OSCC. We found that the expression levels of miR-99b-3p decreased in 21 clinical OSCC samples (84%). Furthermore, ectopic expression of miR-99b-3p inhibited OSCC cell proliferation by downregulating glycogen synthase kinase-3β (GSK3β), an miR-99b-3p' target gene, at the mRNA and protein levels, both in vitro and in vivo. Moreover, the silencing of GSK3β recapitulated the cellular and molecular effects in a similar manner to the overexpression of miR-99b-3p, which included inhibition of OSCC cell proliferation and suppression of p65 (RelA) and G1 regulators (cyclin D1, CDK4 and CDK6) in vitro. Our data suggest that miR-99b-3p functions as a tumor suppressor in OSCC via GSK3β downregulation.

Die Prognose von Patienten mit metastasierten kolorektalen Karzinomen ist weiterhin schlecht und liegt trotz Einsatz neuerer Substanzen im Median bei 20–24 Monaten. Die aktuell wirkungsvollsten Chemotherapien bestehen aus Kombinationsschemata von 5-Fluorouracil (5-FU) mit Irinotecan oder Oxaliplatin. Neben diesen Chemotherapeutika ist eine neue Klasse zielgerichteter molekularer Substanzen entwickelt worden, die z.B. die Angiogenese hemmen oder bestimmte Wachstumsfaktoren bzw. deren Rezeptoren blockieren und so eine antineoplastische Wirkung entfalten sollen. Die Vorstellung ist, dass z.B. mit spezifischen Antikorpern nur solche Tu morzellen gezielt angegriffen und in ihrem Wachstum gehindert werden, die die entsprechenden Rezeptoren besitzen. Die wichtigsten bislang zugelassenen biologischen Substanzen sind Bevacizumab, ein monoklonaler Antikorper gegen den Va scular Endothelial Growth Factor, oder Cetuximab, ein Antikorper gegen den Epidermal Growth Factor Receptor (EGFR oder ErbB1) [De Roock, et al. 2007]. In Kombination mit konventionellen Chemotherapeutika konnen Ansprechraten bis 60% erreicht und dadurch das progressionsfreie Uberleben und zum Teil das Gesamtuberleben verlangert werden. Die Suche nach neuen zielgerichteten Therapien hat dazu gefuhrt, dass derzeit eine ganze Reihe neuer Substanzen in klinischen Therapiestudien gepruft werden, mit zum Teil viel versprechenden Ansatzen. Allen ist gemeinsam, dass selektiv Tu morzellen (oder beispielsweise das zum Tumor gehorige Gefassystem) angesteuert und zielgenau behandelt werden sollen, die Rezeptoren aufweisen, gegen die der Antikorper gerichtet ist. Ein neuer, voll humanisierter Antikorper, der ebenfalls fur den EGF-Rezeptor spezifisch ist [Berlin et al. 2006], Panitumumab, wurde vor kurzem ebenfalls zugelassen.

MicroRNAs (miRNAs) have been shown to play essential roles in regulating the activity of human hepatocellular carcinoma (HCC) cells, thereby contributing to the suppression of invasion and metastasis. In this study, using gain and loss of function assays, we demonstrated that miR-302b was frequently down-regulated in clinical HCC specimens, as compared with 15 corresponding adjacent normal tissues. Overexpression of miR-302b suppressed HCC cell invasion and metastasis. Regulation of NF-κB and matrix metalloproteinase (MMP)-2 expression by miR-302b was mediated via AKT2 in SMMC-7721 cells. Silencing AKT2 produced effects similar to those of miR-302b overexpression, which included inhibiting SMMC-7721 cell invasion and metastasis and dereasing NF-κB and MMP-2 expression. Furthermore, overexpression of AKT2 attenuated the effects of miR-302b overexpression. Taken together, our findings indicate that miR-302b inhibits SMMC-7721 cell invasion and metastasis by targeting AKT2, suggesting that miR-302b might represent a potential therapeutic target for HCC intervention.

// Su’e Chang 1 , Ling Gao 1, 2 , Yang Yang 1 , Dongdong Tong 1 , Bo Guo 1 , Liying Liu 1 , Zongfang Li 3 , Tusheng Song 1 , Chen Huang 1 1 Department of Genetics and Molecular Biology/Key Laboratory of Environment and Genes Related to Diseases, College of Medicine, Xi’an Jiaotong University, Xi’an, Shaanxi, P. R. China 2 Department of Oral Maxillofacial Surgery, Stomatology Hospital of Xi’an Jiaotong University College of Medicine, Xi’an, Shaanxi, P. R. China 3 Department of General Surgery, the Second Affiliated Hospital, School of Medicine, Xi’an Jiaotong University, Xi’an, Shaanxi, P. R. China Correspondence to: Chen Huang, e-mail: hchen@mail.xjtu.edu.cn Keywords: 1,25(OH) 2 D 3 , miR-145, gastric cancer, E2F3, proliferation Received: October 20, 2014 Accepted: January 06, 2015 Published: February 18, 2015 ABSTRACT VitaminD3 signaling is involved in inhibiting the development and progression of gastric cancer (GC), while the active vitamin D metabolite 1-alpha,25-dihydroxyvitamin D3 (1,25(OH) 2 D 3 )-mediated gene regulatory mechanisms in GC remain unclear. We found that miR-145 is induced by 1,25(OH) 2 D 3 in a dose- and vitamin D receptor (VDR)-dependent manner in GC cells. Inhibition of miR-145 reverses the antiproliferative effect of 1,25(OH) 2 D 3 . Furthermore, miR-145 expression was lower in tumors compared with matched normal samples and correlated with increased the E2F3 transcription factor protein staining. Overexpression of miR-145 inhibited colony formation, cell viability and induced cell arrest in S-phase in GC cells by targeting E2F3 and CDK6. miR-145 inhibition consistently abrogates the 1,25(OH) 2 D 3 -mediated suppression of E2F3 , CDK6 , CDK2 and CCNA2 genes. Altogether, our results indicate that miR-145 mediates the antiproliferative and gene regulatory effects of vitamin D3 in GC cells and might hold promise for prognosis and therapeutic strategies for GC treatment.

MicroRNAs (miRNAs) are important gene regulators that participate in tumorigenesis. Previous studies have implicated that miR-214 is a tumor suppressor that is capable of inhibiting human hepatocellular carcinoma (HCC) cell growth. However, the mechanism by which miR-214 suppresses tumor development remains unknown. In the present study, miR-214 was observed to suppress tumor proliferation by directly targeting E2F transcription factor 3 (E2F3) in HCC cells. Colony formation, cell cycle and proliferation assays were employed to study the tumor suppressor role of miR-214 in cell proliferation. In addition, western blotting and dual-luciferase reporter assays were used to evaluate whether E2F3 was a target of miR-214. The results of these analyses revealed that E2F3 was a novel target of miR-214. Furthermore, enhanced expression of miR-214 or silencing of E2F3 inhibited the proliferation of HCC SMMC-7721 cells. These findings suggest that miR-214 suppresses HCC growth by targeting E2F3, and may provide a novel approach for the treatment of human HCC.

Despite being already known that p27 can regulate cell proliferation, cell motility and apoptosis, the role of p27 expression in oral squamous cell carcinoma (OSCC) remains controversial. The purpose of this study was to comprehensively evaluate, with a meta-analysis, the clinicopathological and prognostic role of p27 expression in OSCC. A meta-analysis of eligible studies was performed to assess the effects of p27 expression on clinicopathological parameters and overall survival (OS) in patients with OSCC, using pooled relative risks with 95% confidence intervals. Heterogeneity and publication bias were also assessed. Fourteen studies involving a total of 1,010 patients met the inclusion criteria. Low p27 expression was significantly associated with advanced TNM stage (p2=34.60, I2=68.2%, p2=14.86, I2=39.4%, p=0.095). We did not detect a significant publication bias in this meta-analysis. Our meta-analysis suggests that p27 expression status might be useful as a predictive biomarker in clinical practice, and might potently predict OS in OSCC patients.