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Objective:To analyze the expression of histone methyltransferase SETD1A and SETD5 in breast cancer and its correlation with the clinicopathological characteristics of patients.Methods:A total of 80 breast cancer patients were included in the study. GSCA website screened SET domain family members, predicted their expression in breast cancer tissues, and verified them with immunohistochemical SP method. Chi-square test and Logistic regression model were used to analyze the correlation between SETD1A, SETD5 and clinicopathological characteristics of patients.Results:The GSCA website showed that the expressions of SETD1A and SETD5 of the SET domain family were up-regulated in breast cancer tissues compared with normal tissues (all P<0.05). Immunohistochemical SP method showed that the positive expression rates of SETD1A and SETD5 in breast cancer tissues were 73.8% and 68.8% respectively, which were significantly higher than the positive expression rates of SETD1A and SETD5 in paracancerous tissues 38.8% ( χ2=19.91, P<0.001) and 32.5% ( χ2=21.03, P<0.001). Chi-square test results showed that the expression of SETD1A was significantly correlated with lymph node metastasis and vascular invasion, and the expression of SETD5 was significantly correlated with nerve invasion (all P<0.05). Logistic regression model showed that SETD1A expression was correlated with lymph node metastasis ( OR=0.07, 95% CI: 0.01-0.25, P<0.001) and molecular type ( OR=0.04, 95% CI: 0.00-0.48, P=0.022), SETD5 expression was correlated with neural invasion ( OR=6.41, 95% CI: 1.45-46.65, P=0.029) . Conclusion:The expressions of histone methyltransferases SETD1A and SETD5 are up-regulated in breast cancer tissues, and they are correlated with pathological features such as lymph node metastasis, vascular invasion, and neural invasion.
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OBJECTIVES@#Silence of SET domain containing lysine methyltransferase 7 (SET7) alleviates myocardial tissue injury caused by ischemia-reperfusion. But the effects of SET7 on angiotensin II (Ang II)-induced myocardial fibroblast proliferation and the collagen synthesis are not clear. The purpose of this study was to explore the effect of SET7 on the proliferation and collagen synthesis of myocardial fibroblasts and its mechanisms.@*METHODS@#Myocardial fibroblasts were isolated and identified by immunofluorescence. Myocardial fibroblasts were randomly divided into 4 groups: a control group (cells were normally cultured), an Ang II group (cells were treated with 100 nmol/L Ang II for 24 h), a siCtrl group (cells were transfected with siRNA control and were then treated with 100 nmol/L Ang II for 24 h), and a siSET7 group (cells were transfected with siRNA SET7 and were then treated with 100 nmol/L Ang II for 24 h). Cell counting kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) assay were used to evaluate cell proliferation. Real-time PCR was used to detect the mRNA levels of SET7, collagen I, collagen III, and α-smooth muscle actin (α-SMA). Western blotting was used to detect the protein expression of SET7, collagen I, collagen III, α-SMA, sonic hedgehog (Shh), ptched1 (Ptch1), and glioma-associated oncogene homolog 1 (Gli1).@*RESULTS@#Fluorescence microscopy showed positive vimentin staining, and myocardial fibroblasts were in good condition. As compared to the control group, the mRNA and protein levels of SET7 in the Ang II group were significantly upregulated; cell proliferation rate and EdU fluorescence intensity in the Ang II group were significantly increased; the mRNA and protein levels of collagen I, collagen III, and α-SMA were significantly upregulated (all @*CONCLUSIONS@#Silence of SET7 gene inhibits Ang II-induced proliferation and collagen synthesis of myocardial fibroblasts. Shh signaling pathway may be involved in this process.
Subject(s)
Angiotensin II/pharmacology , Cell Proliferation , Cells, Cultured , Collagen/genetics , Fibroblasts , Hedgehog ProteinsABSTRACT
Objective • To investigate the effect of V-set domain containing T cell activation inhibitor 1 (VTCN1) on long noncoding RNAs (lncRNAs) and mRNAs expression in colon cancer cells. Methods • VTCN1 was overexpressed by lentivirus plasmid in colon cancer cell line SW1116. RNA was extracted and sequenced. The differentially expressed lncRNAs and mRNAs were compared with the negative control group. The accuracy of RNA sequencing was verified by real-time quantitative PCR (qRT-PCR) using three differentially expressed lncRNAs and two mRNAs. BLAST2GO and Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to analyze and predict the functions of these differentially expressed lncRNAs and mRNAs. The online platform GEPIA18 (Gene Expression Profiling Interactive Analysis) was used to analyze the correlation between differentially expressed lncRNAs and survival of patients with colorectal cancer. Results • A total of 167 differential genes, i.e., 39 lncRNAs and 128 mRNAs, were identified by RNA sequencing in VTCN1 overexpressed SW1116 cells. The results of qRT-PCR were consistent with those of RNA sequencing. Bioinformatics analysis showed that these different genes regulated by VTCN1 may be involved in endoplasmic reticulum protein processing and RNA monitoring signaling pathways. In addition, three lncRNAs (DNA JC9-AS1, HCG27, and RP11-339B21.13), which were significantly up-regulated in colorectal cancer cells overexpressing VTCN1, were also independent predictors of overall survival of colorectal cancer patients. Conclusion • In colon cancer cells, VTCN1 regulates several downstream lncRNAs and mRNAs, which may be involved in endoplasmic reticulum protein processing and mRNA monitoring signaling pathways.
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Objective • To investigate the effect of histone H3K14M mutation on the activity of methyltransferase RomA, a secreted effector ofLegionella pneumophila in eukaryotic cells and the underlying mechanisms. Methods • Wide-type histone H3 (H3WT) and mutant histone H3 (the lysine residue 14 was replaced by methionine, isoleucine or arginine residue, and named as H3K14M, H3K14I, and H3K14R, respectively) recombinant expression plasmids were constructed. Packaged lentiviruses with these plasmids were used to infect eukaryotic cells 293T and THP-1 with or without over-expression of RomA. The H3K14 methylation and acetylation were analyzed by Western blotting. The interaction of RomA with H3WT and H3K14 mutants was detected by co-immunoprecipitation. Results • A secreted effector of Legionella pneumophila named RomA targeted the host cell nucleus to upregulate the H3K14 methylation level and downregulate the H3K14 acetylation level for inhibiting the gene expression in host cells and promoting Legionella pneumophila's efficient intracellular replication. But histone H3K14M mutation could promote the interaction between H3K14M and RomA and thus inhibited the methyltransferase activity of RomA. Conclusion • Histone H3K14M mutation significantly inhibits the activity of Legionella pneumophilamethyltransferase RomA.
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BACKGROUND: SET domain bifurcated 1 (SETDB1) has been widely considered as an oncogene playing a critical role in many human cancers, including breast cancer. Nevertheless, the molecular mechanism by which SETDB1 regulates breast cancer tumorigenesis is still unknown. METHODS: qRT-PCR assay or western blot analysis was performed to assess the expression level of SETDB1 mRNA or protein, respectively. siSETDB1, pCMV6-XL5-SETDB1, miR-381-3p mimic, or miR-381-3p inhibitor was transfected into cells to regulate the expression of SETDB1 or miR-381-3p. MiRNA directly interacted with SETDB1 was verified by luciferase reporter assay and RNA immunoprecipitation. CCK-8 assay, colony formation assay, flow cytometric analysis, and transwell assay were used to detect the abilities of cell proliferation, cell cycle progression and migration, respectively. Animal model of xenograft tumor was used to observe the regulatory effect of SETDB1 on tumor growth in vivo. RESULTS: We verified that SETDB1 mRNA level was upregulated in breast cancer tissues and cell lines, and SETDB1 depletion led to a suppression of cell proliferation, cell cycle progression and migration in vitro, as well as tumor growth in vivo. SETDB1 was verified to be a target of miR-381-3p. Moreover, miR-381-3p overexpression suppressed cell proliferation, cell cycle progression and migration, whereas SETDB1 abated miR-381-3p-mediated regulatory function on breast cancer cells. CONCLUSIONS: This study revealed that SETDB1 knockdown might suppress breast cancer progression at least partly by miR-381-3p-related regulation, providing a novel prospect in breast cancer therapy.