LINC01128 facilitates the progression of pancreatic cancer through up-regulation of LDHA by targeting miR-561-5p.

ABSTRACT

BACKGROUND: Long non-coding RNAs (lncRNAs) regulate tumor development and metastasis in several types of cancers through various molecular mechanisms. However, the biological role of most lncRNAs in pancreatic cancer (PC) remains unclear. Here, we explored the expression, biological functions, and molecular mechanism of LINC01128 in PC. METHODS: Quantitive reverse transcription PCR was used to detect the expression level of LINC01128 in PC tissues and different PC cell lines. A loss-of-function and gain-of-function experiment was used to explore the biological effects of LINC01128 on PC carcinogenesis in vitro and in vivo. Western blot analysis, subcellular fractionation experiment, luciferase reporter gene assay, and MS2-RNA immunoprecipitation experiment were used to study the potential molecular mechanism of LINC01128 during carcinogenesis. RESULTS: The expression of LINC01128 was upregulated in PC tissues and cell lines, and overexpression of LINC01128 was significantly related to the poor prognosis of patients with PC. Furthermore, silencing LINC01128 significantly inhibited the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of PC cells in vitro and tumor growth in vivo, while LINC01128 overexpression promoted these processes. Further research showed that LINC01128 acted as a sponge for microRNA miR-561-5p, and lactate dehydrogenase A (LDHA) was the downstream target gene of miR-561-5p. It was also revealed that the expression of miR-561-5p in PC was decreased, and a negative correlation between miR-561-5p and LINC01128 was revealed. Based on rescue experiments, LDHA overexpression partially restored the inhibitory effect of LINC01128 knockdown on proliferation, migration, and invasion of PC cells. CONCLUSIONS: LINC01128 promotes the proliferation, migration, invasion, and EMT of PC by regulating the miR-561-5p/LDHA axis, suggesting LINC01128 may be a new prognostic marker and therapeutic target in PC.