LncRNA LEF1-AS1 promotes metastasis of prostatic carcinoma via the Wnt/β-catenin pathway

BACKGROUND: Long noncoding RNAs (lncRNAs) are important functional regulators of many biological processes of cancers. However, the mechanisms by which lncRNAs modulate androgen-independent prostate cancer (AIPC) development remain largely unknown. METHODS: Next-generation sequencing technology and RT-qPCR were used to assess LEF1-AS1 expression level in AIPC tissues and adjacent normal tissues. Functional in vitro experiments, including colony formation, EDU and transwell assays were performed to assess the role of LEF1-AS1 in AIPC. Xenograft assays were conducted to assess the effect of LEF1-AS1 on cell proliferation in vivo. Chromatin immunoprecipitation (ChIP) and RNA binding protein immunoprecipitation (RIP) assays were performed to elucidate the regulatory network of LEF1-AS1. RESULTS: The next-generation sequencing results showed that LEF1-AS1 is significantly overexpressed in AIPC. Furthermore, our RT-qPCR assay data showed that LEF1-AS1 is overexpressed in AIPC tissues. Functional experiments showed that LEF1-AS1 promotes the proliferation, migration, invasion and angiogenic ability of AIPC cells in vitro and tumour growth in vivo by recruiting the transcription factor C-myb to the promoter of FZD2, inducing its transcription. Furthermore, LEF1-AS1 was shown to function as a competing endogenous RNA (ceRNA) that sponges miR-328 to activate CD44. CONCLUSION: In summary, the results of our present study revealed that LEF1-AS1 acts as a tumour promoter in the progression of AIPC. Furthermore, the results revealed that LEF1-AS1 functions as a ceRNA and regulates Wnt/β-catenin pathway activity via FZD2 and CD44. Our results provide new insights into the mechanism that links the function of LEF1-AS1 with AIPC and suggests that LEF1-AS1 may serve as a novel potential target for the improvement of AIPC therapy.