Epigenetic silencing of E-cadherin gene induced by lncRNA MALAT-1 in acute myeloid leukaemia.

Epigenetic abnormalities in acute myeloid leukaemia provide us with a target for novel therapeutic strategies. The aim of the study was to verify the epigenetic regulatory mechanism of E-cadherin gene silencing induced by long non-coding RNA MALAT-1 in AML. Expression of MALAT-1, E-cadherin, EZH2, SUZ12 and EED genes in AML patients was detected by RT-qPCR. After MALAT-1 silencing in AML cell lines, levels of the E-cadherin, EZH2, SUZ12, EED, DNMT1, DNMT3A and DNMT3B genes and encoded proteins were detected by RT-qPCR and Western blotting. The level of CpG island methylation and trimethylation modification of histone H3K27 in the promoter region of E-cadherin was detected by pyrosequencing and ChIP-qPCR. RIP-qPCR was used to detect the interaction between MALAT-1 and proteins. MALAT-1, EZH2 and EED gene expression was markedly increased in AML patients with E-cadherin down-regulation. A positive correlation between EZH2 or SUZ12 and MALAT-1 expression was observed. After MALAT-1 silencing, the expression of E-cadherin was up-regulated, whereas the expression of EZH2, SUZ12, DNMT1, DNMT3A and DNMT3B was down-regulated. Results of Western blotting were consistent with those of RT-qPCR. Methylation levels of E-cadherin in AML patients were higher than that in normal controls, which appeared to increase with age. Methylation of the CpG island and H3K27 trimethylation of E-cadherin were decreased after MALAT-1 silencing. RIP-qPCR suggested that MALAT-1 might be enriched by EZH2 and SUZ12. Our findings verified that MALAT-1 might lead to the transcriptional silencing of E-cadherin gene through the trimethylation of H3K27 mediated by recruiting EZH2 and SUZ12.

Huang J ，Fang J ，Chen Q ，Chen J ，Shen J ... -  《-》

LncRNA HOTAIR regulates the expression of E-cadherin to affect nasopharyngeal carcinoma progression by recruiting histone methylase EZH2 to mediate H3K27 trimethylation.

There has been increasing evidence for the function of long non-coding RNA (lncRNA) in nasopharyngeal carcinoma (NPC). We aim to delve into the position of lncRNA HOX antisense intergenic RNA (HOTAIR), together with enhancer of zeste homolog 2 (EZH2), E-cadherin and trimethylation of lysine 27 on histone H3 (H3K27me3) in NPC. HOTAIR, EZH2, and E-cadherin expression in NPC tissues and cells were tested. NPC cell biological functions were examined through gain-of and loss-of function assays. The mechanism of lncRNA HOTAIR/E-cadherin/EZH2/H3K27 axis in NPC was decoded. LncRNA HOTAIR and EZH2 were highly expressed in NPC, and E-cadherin was lowly expressed. Down-regulation of HOTAIR or EZH2 inhibited NPC cell progression and tumor growth. HOTAIR recruited histone methylase EZH2 to mediate trimethylation of H3K27 and regulated E-cadherin expression. HOTAIR inhibits E-cadherin by stimulating the trimethylation of H3K27 to promote NPC cell progression through recruiting histone methylase EZH2.

Yang FL ，Wei YX ，Liao BY ，Wei GJ ，Qin HM ，Pang XX ，Wang JL ... -  《-》

EZH2 promotes cell migration and invasion but not alters cell proliferation by suppressing E-cadherin, partly through association with MALAT-1 in pancreatic cancer.

Han T ，Jiao F ，Hu H ，Yuan C ，Wang L ，Jin ZL ，Song WF ，Wang LW ... -  《Oncotarget》

ELK1-Induced upregulation of long non-coding TNK2-AS1 promotes the progression of acute myeloid leukemia by EZH2-mediated epigenetic silencing of CELF2.

Guo D ，Zhang A ，Suo M ，Wang P ，Liang Y ... -  《-》

Long non-coding RNA HOTAIR mediates the switching of histone H3 lysine 27 acetylation to methylation to promote epithelial-to-mesenchymal transition in gastric cancer.

Song Y ，Wang R ，Li LW ，Liu X ，Wang YF ，Wang QX ，Zhang Q ... -  《-》