Elevated expression level of long noncoding RNA MALAT-1 facilitates cell growth, migration and invasion in pancreatic cancer

Abstract
Pancreatic cancer is one of the most aggressive solid malignancies with a dismal survival rate. Recent studies have shown that high expression levels of long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript-1 (MALAT-1) correlate with several solid tumors. However, the underlying molecular mechanisms and its clinical significance in pancreatic cancer remain to be elucidated. In the present study, our results showed that MALAT-1 expression levels were upregulated in pancreatic cancer tissues compared with adjacent noncancerous controls. Consistently, higher expression level of MALAT-1 was found in all seven pancreatic cancer cell lines relative to the human pancreatic ductal epithelial cell. Further function analysis revealed that downregulation of MALAT-1 could inhibit tumor cell proliferation and decrease cell migration and invasion in vitro. The underlying mechanisms are possibly involved in inducing G2/M cell cycle arrest, promoting cell apoptosis, suppressing epithelial-mesenchymal transition and reducing cancer stem-like properties. In conclusion, this study indicated that MALAT-1 may serve as an oncogenic lncRNA that is involved in malignancy phenotypes of pancreatic cancer. Therefore, it may be used as a potential therapeutic target.