Hao Liu1, Kaihuan Yu1, Peng Ma1, Liangkun Xiong1, Maoming Wang1, Weixing Wang2. 1. Department of Hepatobiliary Surgery in East Hospital, Renmin Hospital of Wuhan University, Wuhan, Hubei, China. 2. Department of Hepatobiliary Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
Abstract
BACKGROUND: Long noncoding RNAs (lncRNAs) play crucial roles in fibrosis process. In our previous RNA-seq study, we found that lncRNA myocardial infarction-associated transcript (MIAT) was differentially expressed in pancreatic tissues of chronic pancreatitis (CP) patients. However, the function of MIAT in CP remains unknown. This study was aimed to investigate the function and underlying mechanism of MIAT in pancreatic fibrosis. MATERIALS AND METHODS: The expression levels of MIAT, miR-216a-3p, cyclooxygenase 2 (COX-2), α-smooth muscle actin (α-SMA), and collagen I were estimated by Western blot analysis and qualitative reverse transcription polymerase chain reaction. The relationships between miR-216a-3p, MIAT, and COX-2 were confirmed by luciferase reporter assay. The proliferation of human pancreatic stellate cells (HPaSteCs) was detected by cell counting kit-8 assay. RESULTS: We found that MIAT, along with the levels of fibrosis-related proteins α-SMA and collagen I, as well as COX-2 were upregulated, while miR-216a-3p was downregulated in transforming growth factor (TGF)-β1-stimulated HPaSteCs. Mechanistically, MIAT acted as a molecular sponge for miR-216a-3p. Furthermore, we identified COX-2 as a direct target of miR-126a-3p. Additionally, MIAT overturned the inhibitory effect of miR-216a-3p overexpression and COX-2 knockdown on the activation and proliferation of HPaSteCs. CONCLUSION: Our study provided mechanistic insights into a critical role for MIAT as a miRNA sponge in CP.
BACKGROUND: Long noncoding RNAs (lncRNAs) play crucial roles in fibrosis process. In our previous RNA-seq study, we found that lncRNA myocardial infarction-associated transcript (MIAT) was differentially expressed in pancreatic tissues of chronic pancreatitis (CP) patients. However, the function of MIAT in CP remains unknown. This study was aimed to investigate the function and underlying mechanism of MIAT in pancreatic fibrosis. MATERIALS AND METHODS: The expression levels of MIAT, miR-216a-3p, cyclooxygenase 2 (COX-2), α-smooth muscle actin (α-SMA), and collagen I were estimated by Western blot analysis and qualitative reverse transcription polymerase chain reaction. The relationships between miR-216a-3p, MIAT, and COX-2 were confirmed by luciferase reporter assay. The proliferation of humanpancreatic stellate cells (HPaSteCs) was detected by cell counting kit-8 assay. RESULTS: We found that MIAT, along with the levels of fibrosis-related proteins α-SMA and collagen I, as well as COX-2 were upregulated, while miR-216a-3p was downregulated in transforming growth factor (TGF)-β1-stimulated HPaSteCs. Mechanistically, MIAT acted as a molecular sponge for miR-216a-3p. Furthermore, we identified COX-2 as a direct target of miR-126a-3p. Additionally, MIAT overturned the inhibitory effect of miR-216a-3p overexpression and COX-2 knockdown on the activation and proliferation of HPaSteCs. CONCLUSION: Our study provided mechanistic insights into a critical role for MIAT as a miRNA sponge in CP.