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author:("Zhan, mixing")
1.  Whole DNA methylome profiling in lung cancer cells before and after epithelial-to-mesenchymal transition 
Diagnostic Pathology  2014;9:66.
Background
Metastatic lung cancer is one of the leading causes of cancer death. In recent years, epithelial-to-mesenchymal transition (EMT) has been found to contribute to metastasis, as it enables migratory and invasive properties in cancer cells. Previous genome-wide studies found that DNA methylation was unchanged during EMT induced by TGF-β in AML12 cells. In this study, we aimed to discover EMT-related changes in DNA methylation in cancer cells, which are poorly understood.
Methods
We employed a next-generation sequencing-based method, MSCC (methyl-sensitive cut counting), to investigate DNA methylation during EMT in the A549 lung cancer cell line.
Results
We found that methylation levels were highly correlated to gene expression, histone modifications and small RNA expression. However, no differentially methylated regions (DMRs) were found in A549 cells treated with TGF-β for 4 h, 12 h, 24 h and 96 h. Additionally, CpG islands (CGIs) showed no overall change in methylation levels, and at the single-base level, almost all of the CpGs showed conservation of DNA methylation levels. Furthermore, we found that the expression of DNA methyltransferase 1, 3a, 3b (DNMT1, DNMT3a, DNMT3b) and ten-eleven translocation 1 (TET1) was altered after EMT. The level of several histone methylations was also changed.
Conclusions
DNA methylation-related enzymes and histone methylation might have a role in TGF-β-induced EMT without affecting the whole DNA methylome in cancer cells. Our data provide new insights into the global methylation signature of lung cancer cells and the role of DNA methylation in EMT.
Virtual slides
The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1112892497119603
doi:10.1186/1746-1596-9-66
PMCID: PMC4108085  PMID: 24655585
DNA methylation; Epithelial-to-mesenchymal transition (EMT); Lung cancer; CpG; CGI; MSCC
2.  THE SPLICING FACTOR SRSF1 REGULATES APOPTOSIS AND PROLIFERATION TO PROMOTE MAMMARY EPITHELIAL CELL TRANSFORMATION 
The splicing-factor oncoprotein SRSF1 (also known as SF2/ASF) is upregulated in breast cancers. We investigated SRSF1’s ability to transform human and mouse mammary epithelial cells in vivo and in vitro. SRSF1-overexpressing COMMA-1D cells formed tumors, following orthotopic transplantation to reconstitute the mammary gland. In 3-D culture, SRSF1-overexpressing MCF-10A cells formed larger acini than control cells, reflecting increased proliferation and delayed apoptosis during acinar morphogenesis. These effects required the first RNA-recognition motif and nuclear functions of SRSF1. SRSF1 overexpression promoted alternative splicing of BIM and BIN1 isoforms that lack pro-apoptotic functions and contribute to the phenotype. Finally, SRSF1 cooperated specifically with MYC to transform mammary epithelial cells, in part by potentiating eIF4E activation, and these cooperating oncogenes are significantly co-expressed in human breast tumors. Thus, SRSF1 can promote breast cancer, and SRSF1 itself or its downstream effectors may be valuable targets for therapeutics development.
doi:10.1038/nsmb.2207
PMCID: PMC3272117  PMID: 22245967
3.  Deregulation of Scribble promotes mammary tumorigenesis and reveals a role for cell polarity in carcinoma 
Cell  2008;135(5):865-878.
Loss of cell polarity proteins such as Scribble induces neoplasia in Drosophila by promoting uncontrolled proliferation. The role polarity proteins play during tumorigenesis in mammals is poorly understood. We demonstrate that knockdown of Scribble in mammary epithelia disrupts cell polarity, blocks three-dimensional morphogenesis, inhibits apoptosis and induces dysplasia in vivo that progress to tumors after long latency. Knockdown of Scribble also cooperates with oncogenes such as Myc to transform epithelial cells in 3D acini and induce tumors in vivo by blocking activation of an apoptosis pathway. Like knockdown, mislocalization of Scribble from cell-cell junction was sufficient to promote cell transformation. Interestingly, spontaneous mammary tumors in mice and humans possess both downregulated and mislocalized Scribble suggesting a selection-pressure for Scribble inactivation. Thus, we demonstrate that Scribble is a novel regulator of breast cancer and that deregulation of polarity pathways promotes dysplastic and neoplastic growth in mammals by disrupting morphogenesis and inhibiting cell death.
doi:10.1016/j.cell.2008.09.045
PMCID: PMC3015046  PMID: 19041750
Myc; Scribble; 3D; mammary epithelia; mammary tumorigenesis; mouse models; epithelial organization; polarity; apoptosis; cell architecture

Results 1-3 (3)