FGD5­AS1 is an oncogenic lncRNA in pancreatic cancer and regulates the Wnt/ß­catenin signaling pathway via miR­577.

The objective of the present study was to clarify the expression characteristics of long non­coding RNA (lncRNA) FGD5 antisense RNA 1 (FGD5­AS1) in pancreatic cancer, as well as its biological function and underlying mechanism. Reverse transcription­quantitative polymerase chain reaction (RT­qPCR) was utilized for the detection of FGD5­AS1 and microRNA (miR)­577 expression levels in pancreatic cancer tissues. Transfection was performed to upregulate or downregulate FGD5­AS1 in pancreatic cancer cell lines. MTT and Transwell assays were then utilized to detect the proliferation, migration and invasion of cancer cells, respectively. Subsequently, dual­luciferase reporter gene assay, RNA immunoprecipitation assay, RNA pull­down assay, RT­qPCR, western blotting, and Pearson's correlation analysis were employed to confirm the regulatory relationships among FGD5­AS1, miR­577, low­density lipoprotein receptor­related protein 6 (LRP6) and ß­catenin. Western blotting was employed to determine the expression levels of Axin2, cyclin D1 and c­Myc. The expression level of FGD5­AS1 was upregulated in pancreatic cancer tissues and cell lines. FGD5­AS1 knockdown inhibited pancreatic cancer cell proliferation, migration and invasion. By contrast, miR­577 was significantly inhibited in pancreatic cancer cells and tissues; its downregulation promoted pancreatic cancer cell proliferation, migration and invasion, and reversed the effects of FGD5­AS1 knockdown on pancreatic cancer cells. In addition, it was revealed that miR­577 was a target of FGD5­AS1, and FGD5­AS1 could modulate the expression levels of LRP6, ß­catenin, Axin2, cyclin D1 and c­Myc via suppressing miR­577. In conclusion, in pancreatic cancer, highly expressed FGD5­AS1 activated the Wnt/ß­catenin signaling and promoted cancer cell proliferation, migration and invasion via suppression of miR­577.

[The role of hypermethylation in promoter region of ubiquitin carboxyl-terminal hydrolase L1 in human esophageal cancer].

OBJECTIVE: To study the association of ubiquitin carboxyl-terminal hydrolase L1 (UCHL1) promoter region methylation with human esophageal cancer. METHODS: Promoter region methylation of UCHL1 was detected by methylation specific PCR (MSP) in esophageal cancer cell lines and tissue samples. The expression of UCHL1 was detected by semi-quantitative RT-PCR and Western blot in esophageal cancer cell lines. 5-Aza-2'-deoxycytidine (5-Aza) was applied to reactivate methylated cell lines. RESULTS: Complete methylation of UCHL1 promoter region was detected in 8 cell lines (KYSE30, KYSE150, KYSE140, KYSE450, KYSE510, TE3, TE7, TE10). Loss of UCHL1 expression was found in 7 cell lines (KYSE30, KYSE150, KYSE140, KYSE450, KYSE510, TE3, TE7). Reduced expression was found in TE10 cell line. Promoter region hypermethylation was correlated with UCHL1 expression in esophageal cancer cell lines. Re-expression of UCHL1 was induced by 5-Aza treatment in KYSE150 and TE3 cell lines. UCHL1 was frequently methylated in human primary esophageal cancer (74.51%, 38/51), while no methylation was detected in normal esophageal mucosa(0/10). No association was found between promoter region methylation and age, gender, tumor location, tumor stage or lymph node metastasis. CONCLUSIONS: UCHL1 is silenced by promoter region hypermethylation in human esophageal cancer. Methylation of UCHL1 is frequently happened to primary esophageal cancer and may play an important role in the tumorigenesis.