• Molecules and Cells
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• v.40 no.2
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• pp.123-132
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• 2017

Insulin signaling is coordinated by insulin receptor substrates (IRSs). Many insulin responses, especially for blood glucose metabolism, are mediated primarily through Irs-1 and Irs-2. Irs-1 knockout mice show growth retardation and insulin signaling defects, which can be compensated by other IRSs in vivo; however, the underlying mechanism is not clear. Here, we presented an Irs-1 truncated mutated mouse ($Irs-1^{-/-}$) with growth retardation and subcutaneous adipocyte atrophy. $Irs-1^{-/-}$ mice exhibited mild insulin resistance, as demonstrated by the insulin tolerance test. Phosphatidylinositol 3-kinase (PI3K) activity and phosphorylated Protein Kinase B (PKB/AKT) expression were elevated in liver, skeletal muscle, and subcutaneous adipocytes in Irs-1 deficiency. In addition, the expression of IRS-2 and its phosphorylated version were clearly elevated in liver and skeletal muscle. With miRNA microarray analysis, we found miR-33 was down-regulated in bone marrow stromal cells (BMSCs) of $Irs-1^{-/-}$ mice, while its target gene Irs-2 was up-regulated in vitro studies. In addition, miR-33 was down-regulated in the presence of Irs-1 and which was up-regulated in fasting status. What's more, miR-33 restored its expression in re-feeding status. Meanwhile, miR-33 levels decreased and Irs-2 levels increased in liver, skeletal muscle, and subcutaneous adipocytes of $Irs-1^{-/-}$ mice. In primary cultured liver cells transfected with an miR-33 inhibitor, the expression of IRS-2, PI3K, and phosphorylated-AKT (p-AKT) increased while the opposite results were observed in the presence of an miR-33 mimic. Therefore, decreased miR-33 levels can up-regulate IRS-2 expression, which appears to compensate for the defects of the insulin signaling pathway in Irs-1 deficient mice.

• Journal of fish pathology
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• v.33 no.1
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• pp.35-43
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• 2020

Hypoxia is a serious problem in the marine ecosystem causing a decline in aquatic resources. MicroRNAs (miRNAs) regulate the expression of genes through binding to the corresponding sequences of their target mRNAs. Especially, miRNAs in the cytoplasm can be secreted into body fluids, which called circulating miRNAs, and the availability of circulating miRNAs as biomarkers for hypoxia has been demonstrated in mammals. However, there has been no report on the hypoxia-mediated changes in the circulating miRNAs in fish. miR-210 is known as the representative hypoxia-responsive circulating miRNA in mammals. To know whether fish miR-210 also respond to hypoxia, we analyzed the change of circulating miR-210 quantity in the serum of olive flounder (Paralichthys olivaceus) in response to hypoxia. The expression of hypoxia related genes, hypoxia inducible factor 1α (HIF-1α) and the heat shock protein 90α (HSP90α) was also analyzed. Similar to the reports from mammals, miR-210-5p and miR-210-3p were significantly increased in the serum of olive flounder in response to hypoxia, suggesting that circulating miR-210 levels in the serum can be used as a noninvasive prognostic biomarker for fish suffered hypoxia. The target genes of miR-210 were related to various biological processes, which explains the major regulatory role of miR-210 in response to hypoxia. The expression of HIF-1α and HSP90α in the tissues was also up-regulated by hypoxia. Considering the critical role of HIF-1α in miR-210 expression and HSP90 in miRNAs function, the present up-regulation of HIF-1α and HSP90α might be related to the increase of circulatory miR-210, and the interaction mechanism among HIF-1α, HSP90α, and hypoxia-responsive microRNAs in fish should be further studied.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.10
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• pp.1674-1682
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• 2020

Objective: This study aimed to elucidate the effect of miR-140 on the proliferation of porcine fetal fibroblasts (PFFs) and identify the target genes of miR-140 in PFFs. Methods: In this study, bioinformatics software was used to predict and verify target genes of miR-140. Quantitative polymerase chain reaction and western blot were used to detect the relationship between miR-140 and its target genes in PFFs. Dual luciferase reporter gene assays were performed to assess the interactions among miR-140, type 1 insulin-like growth factor receptor (IGF1R), and SRY-box 4 (SOX4). The effect of miR-140 on the proliferation of PFFs was measured by CCK-8 when PFFs were transfected with a miR-140 mimic or inhibitor. The transcription factor SOX4 binding to promoter of IGF1R was detected by chromatin immunoprecipitation assay (ChIP). Results: miR-140 directly targeted IGF1R and inhibited proliferation of PFFs. Meanwhile, miR-140 targeted transcription factor SOX4 that binds to promoter of porcine IGF1R to indirectly inhibit the expression of IGF1R. In addition, miR-140 inhibitor promoted PFFs proliferation, which is abrogated by SOX4 or IGF1R knockdown. Conclusion: miR-140 inhibited PFFs proliferation by directly targeting IGF1R and indirectly inhibiting IGF1R expression via SOX4, which play an important role in the development of porcine fetal.

• Journal of Cancer Prevention
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• v.22 no.1
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• pp.33-39
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• 2017

Background: MicroRNAs (miRNAs) are key post-translational mechanisms which can regulate gene expression in gastric carcinogenesis. To identify miRNAs responsible for gastric carcinogenesis, we compared expression levels of miRNAs between gastric cancer tissue and non-cancerous gastric mucosa according to Helicobacter pylori status. Methods: Total RNA was extracted from the cancerous regions of formalin-fixed, paraffin-embedded tissues of H. pylori-positive (n = 8) or H. pylori-negative (n = 8) patients with an intestinal type of gastric cancer. RNA expression was analyzed using a 3,523 miRNA profiling microarray based on the Sanger miRBase. Validation analysis was performed using TaqMan miRNA assays for biopsy samples from 107 patients consisted of control and gastric cancer with or without H. pylori. And then, expression levels of miRNAs were compared according to subgroups. Results: A total of 156 miRNAs in the aberrant miRNA profiles across the miRNA microarray showed differential expression (at least a 2-fold change, P < 0.05) in cancer tissue, compared to noncancerous mucosa in both of H. pylori-negative and -positive samples. After 10 promising miRNAs were selected, validations by TaqMan miRNA assays confirmed that two miRNAs (hsa-miR-135b-5p and hsa-miR-196a-5p) were significantly increased and one miRNA (hsa-miR-145-5p) decreased in cancer tissue compared to non-cancerous gastric mucosa at H. pylori-negative group. For H. pylori-positive group, three miRNAs (hsa-miR-18a-5p, hsa-miR-135b-5p, and hsa-miR-196a-5p) were increased in cancer tissue. hsa-miR-135b-5p and hsa-miR-196a-5p were increased in gastric cancer in both of H. pylori-negative and -positive. Conclusions: miRNA expression of the gastric cancer implies that different but partially common gastric cancer carcinogenic mechanisms might exist according to H. pylori status.

• Food Science and Industry
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• v.47 no.3
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• pp.33-38
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• 2014

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6569-6572
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• 2013

In cervical cancer, one of the most common malignant tumors in women worldwide, miR-126 has been reported to exhibit decreased expression. However, its role in cervical cancer cell proliferation and drug sensitivity has remained relatively unexplored. Here, we compared the expression of miR-126 in cervical cancer tissues (n = 20) with that in normal cervical tissue (n = 20) using quantitative RT-PCR. The viability of Siha cervical cancer cells was further measured by MTT assay after transfection with miR-126 mimic (Siha-miR-126 mimic) or microRNA mimic negative control (Siha-miR mimic NC) and after treatment with various concentrations of bleomycin (BLM). IC50s were calculated, and the survival rates (SRs) of Siha cells were calculated. miR-126 expression in cervical cancer tissue was significantly decreased compared with that in normal cervical tissue (P < 0.01). The relative SRs of Siha-miR-126 mimic cells were also significantly decreased compared with those of Siha-miR mimic NC cells at 24-96 h after transfection. The IC50 of BLM in Siha-miR-126 mimic cells ($50.3{\pm}2.02{\mu}g/mL$) was decreased compared with that in Siha-miR mimic NC cells ($70.5{\pm}4.33{\mu}g/mL$) at 48 h after transfection (P < 0.05). Finally, the SRs of Siha-miR-126 mimic cells were significantly lower than those of SihamiR mimic NC cells after cultured in medium containing 40 ${\mu}g/mL$ BLM for 24-96 h (P < 0.05). These results suggest that miR-126 is expressed at low levels in cervical cancer. Upregulation of miR-126 inhibited cervical cancer cell proliferation and enhanced the sensitivity to BLM. Thus, miR-126 may represent a novel approach to cervical cancer treatment.

• Journal of Microbiology and Biotechnology
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• v.33 no.3
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• pp.398-409
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• 2023

LncRNAs play crucial roles in the progression of colon adenocarcinoma (COAD), but the role of LINC01232 in COAD has not received much attention. The present study was designed to explore the related mechanisms of LINC01232 in the progression of COAD. LINC01232, miR-181a-5p, p53, c-myc, Bcl-2, cyclin D1, p16, Bax, VEGF, E-cadherin, vimentin, N-cadherin and SDAD1 expressions were determined by western blot and qRT-PCR. CCK-8, tubule formation, and Transwell assays were employed to detect proliferation, angiogenesis, and migration/invasion of COAD cells, respectively. The relationship between LINC01232 and miR-181a-5p was predicted by LncBase Predicted v.2, and then verified through dual luciferase reporter gene assay. According to the results, LINC01232 was highly expressed in COAD cells and enhanced proliferation, angiogenesis, migration, and invasion of COAD cells. Downregulated LINC01232 promoted expression of p53 and p16, and inhibited c-myc, Bcl-2 and cyclin D1 expressions in COAD cells, while upregulation of LINC01232 generated the opposite effects. LINC01232 was negatively correlated with miR-181a-5p while downregulated miR181a-5p could reverse the effects of siLINC01232 on cell proliferation, angiogenesis, migration, and invasion. Similarly, miR-181a-5p mimic could also offset the effect of LINC01232 overexpression. SiLINC01232 increased the expressions of Bax and E-cadherin, and decreased the expressions of VEGF, vimentin, N-cadherin and SDAD1, which were partially attenuated by miR-181a-5p inhibitor. Collectively, LINC01232 enhances the proliferation, migration, invasion, and angiogenesis of COAD cells by decreasing miR-181a-5p expression.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3961-3968
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• 2015

Background: Variants of human papillomavirus (HPV) show more oncogenicity than do prototypes. The HPV16 Asian variant (HPV16As) plays a major role in cervical cancer of Asian populations. Some amino acid changes in the E6 protein of HPV16 variants affect E6 functions such as p53 interaction and host immune surveillance. This study aimed to investigate activities of HPV16As E6 protein on modulation of expression of miRNA-21 as well as interferon regulatory factors (IRFs) 1, 3, 7 and c-fos. Materials and Methods: Vectors expressing E6 protein of HPV16As (E6D25E) or HPV16 prototype (E6Pro) were constructed and transfected into C33A cells. HCK1T cells expressing E6D25E or E6Pro were established by transducing retrovirus-containing E6D25E or 16E6Pro. The E6AP-binding activity of E6 and proliferation of the transfected C33A cells were determined. MiR-21 and mRNA of interesting genes were detected in the transfected C33A cells and/or the HCK1T cells, with or without treatment by culture medium from HeLa cells (HeLa-CM). Results: E6D25E showed binding activity with E6AP similar to that of E6Pro. Interestingly, E6D25E showed a higher activity of miR-21 induction than did E6Pro in C33A cells expressing E6 protein. This result was similar to the HCK1T cells expressing E6 protein, with HeLa-CM treatment. The miR-21 up-regulation significantly corresponded to its target expression. Different levels of expression of IRFs were also observed in the HCK1T cells expressing E6 protein. Interestingly, when treated with HeLa-CM, IRFs 1, 3 and 7 as well as c-fos were significantly suppressed in the HCK1T cells expressing E6D25E, whereas those in the HCK1T cells expressing E6Pro were induced. A similar situation was seen for IFN-${\alpha}$ and IFN-${\beta}$. Conclusions: E6D25E of the HPV16As variant differed from the E6 prototype in its activities on epigenetic modulation and immune surveillance and this might be a key factor for the important role of this variant in cervical cancer progression.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.12
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• pp.1873-1884
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• 2020

The demand for food is increasing day by day because of the increasing global population. Therefore, meat, the easiest and largely available source of protein, needs to be produced in large amounts with good quality. The pork industry is a significant shareholder in fulfilling the global meat demands. Notably, myogenesis- development of muscles during embryogenesis- is a complex mechanism which culminates in meat production. But the molecular mechanisms which govern the myogenesis are less known. The involvement of miRNAs in myogenesis and meat quality, which depends on factors such as myofiber composition and intramuscular fat contents which determine the meat color, flavor, juiciness, and water holding capacity, are being extrapolated to increase both the quantity and quality of pork. Various kinds of microRNAs (miRNAs), miR-1, miR-21, miR22, miR-27, miR-34, miR-127, miR-133, miR-143, miR-155, miR-199, miR-206, miR-208, miR-378, and miR-432 play important roles in pig skeletal muscle development. Further, the quality of meat also depends upon myofiber which is developed through the expression of different kinds of miRNAs at different stages. This review will focus on the mechanism of myogenesis, the role of miRNAs in myogenesis, and meat quality with a focus on the pig.

• Molecules and Cells
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• v.41 no.5
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• pp.390-400
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• 2018

Studies have revealed that miR-103a-3p contributes to tumor growth in several human cancers, and high miR-103a-3p expression is associated with poor prognosis in advanced gastric cancer (GC) patients. Moreover, bioinformatics analysis has shown that miR-103a-3p is upregulated in The Cancer Genome Atlas (TCGA) stomach cancer cohort. These results suggest that miR-103a-3p may function as an oncogene in GC. The present study aimed to investigate the role of miR-103a-3p in human GC. miR-103a-3p expression levels were increased in 33 clinical GC specimens compared with adjacent nontumor stomach tissues. Gain- and loss-of-function studies were performed to identify the correlation between miR-103a-3p and tumorigenesis in human GC. Inhibiting miR-103a-3p suppressed GC cell proliferation and blocked the S-G2/M transition in MKN-45/SGC-7901 cells, whereas miR-103a-3p overexpression improved GC cell proliferation and promoted the S-G2/M transition in vitro. Bioinformatics and dual-luciferase reporter assays confirmed that ATF7 is a direct target of miR-103a-3p. Analysis of the TCGA stomach cancer cohort further revealed that miR-103a-3p expression was inversely correlated with ATF7 expression. Notably, silencing ATF7 showed similar cellular and molecular effects as miR-103a-3p overexpression, namely, increased GC cell proliferation, improved CDK2 expression and decreased P27 expression. ATF7 overexpression eliminated the effects of miR-103a-3p expression. These findings indicate that miR-103a-3p promotes the proliferation of GC cell by targeting and suppressing ATF7 in vitro.