MALAT1 promotes cell proliferation in gastric cancer by recruiting SF2/ASF

The functions of long non-coding RNAs (lncRNAs) in gastric cancer (GC) remain largely unknown. MALAT1 is a kind of lncRNA that had been validated as a pivotal metastasis and prognosis mark in lung adenocarcinoma. In this study, we found that MALAT1 was aberrantly highly expressed in GC cell lines (SGC-7901, MKN-45 and SUN-16), and induced specific distribution and over-expression of SF2/ASF in nucleolus. Knock-down of MALAT1 or SF2/ASF in SGC-7901 cells respectively induced significant arrest of cell cycle in G0/G1 phase along with a remarkable suppression of cell proliferation, and the nuclear distribution and expression of SF2/ASF was significantly impaired when MALAT1 was depleted. However, over-expression of SF2/ASF exhibited no effect on rescuing the cell proliferation suppression by MALAT1 depletion. These results suggest that MALAT1 may function as a promoter of GC cell proliferation partly by regulating SF2/ASF, and our findings may provide us a likely biomarker and a potential target for GC diagnosis and therapeutic treatment. (C) 2014 Published by Elsevier Masson SAS.