Overexpressed MALAT1 promotes invasion and metastasis of gastric cancer cells via increasing EGFL7 expression.
OBJECTIVE
Long non-coding RNAs (lncRNAs) have been demonstrated to participate in various cancers. Here, the role and its potential mechanism of MALAT1 in invasion and migration of gastric cancer (GC) were investigated.


METHODS
Gastric adenocarcinoma tissues and matched normal adjacent tissues were isolated from 25 patients with GC. The expression of epidermal growth factor-like domain-containing protein 7 (EGFL7) was detected in the normal gastric mucosa epithelial GES-1 cell line and three different differentiation GC cell lines, including MKN28 (well-differentiated adenocarcinoma), SGC7901 (moderately differentiated adenocarcinoma) and BGC823 (poorly differentiated adenocarcinoma). Tumor xenotransplant mouse model was established with the injection of cell line pretreated with lentiviral vectors for si-MALAT1 or si-control.


RESULTS
The expression of MALAT1 was up-regulated in GC tissues and three cell lines. Si-MALAT1/pcDNA-MALAT1 induced the decrease of cell invasion and migration, while the effects were reversed by the transfection of pcDNA-EGFL7/si-EGFL7. ChIP assay showed that MALAT1 regulated EGFL7 expression by altering the level of H3 histone acetylation in EGFL7 promoter. In tumor xenotransplant mice, down-regulated MALAT1 contributed to the inhibition of tumor metastasis.


CONCLUSIONS
Up-regulated MALAT1 promoted the invasion and metastasis of GC, and the increase of EGFL7 expression was a potential mechanism via altering its H3 histone acetylation level.
Department of Gastroenterology, Affiliated Hospital, Logistics University of Chinese People's Armed Police Forces, Tianjin 300162, China. Electronic address: quanjdeng@163.com.
Quan-Jun
QJ
Deng
Department of Gastroenterology, Affiliated Hospital, Logistics University of Chinese People's Armed Police Forces, Tianjin 300162, China.
Li-Qun
LQ
Xie
Department of Gastroenterology, Affiliated Hospital, Logistics University of Chinese People's Armed Police Forces, Tianjin 300162, China.
Hua
H
Li
D000107:Acetylation; D000818:Animals; D002135:Calcium-Binding Proteins; D045744:Cell Line, Tumor; D015536:Down-Regulation; D066255:EGF Family of Proteins; D016228:Endothelial Growth Factors / Q000235:genetics*; D064593:Heterografts; D006657:Histones / Q000378:metabolism; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D009361:Neoplasm Invasiveness / Q000235:genetics*; D009362:Neoplasm Metastasis / Q000235:genetics*; D062085:RNA, Long Noncoding / Q000502:physiology*; D013274:Stomach Neoplasms / Q000473:pathology*; D015854:Up-Regulation
D002135:Calcium-Binding Proteins; D066255:EGF Family of Proteins; C527877:EGFL7 protein, human; D016228:Endothelial Growth Factors; D006657:Histones; C557041:MALAT1 long non-coding RNA, human; D062085:RNA, Long Noncoding
EGFL7; Gastric cancer; MALAT1; Metastasis; lncRNA