Long non-coding RNA HOXD-AS1 promotes tumor progression and predicts poor prognosis in colorectal cancer

Mounting evidence has indicated that long non-coding RNAs (lncRNA) serve important roles in tumor development. Previous studies have demonstrated that the lncRNA HOXD cluster antisense RNA 1 (HOXD-AS1) promotes tumor progression in numerous types of cancer; however, the role of HOXD-AS1 in colorectal cancer (CRC) remains unclear. In the present study, the expression levels of HOXD-AS1 were detected in CRC tissues and cell lines using quantitative polymerase chain reaction. In addition, the biological effects of HOXD-AS1 on CRC were evaluated in vitro by cell counting kit-8, colony formation and Transwell assays, and in vivo by tumorigenesis and metastasis assays. The results demonstrated that HOXD-AS1 was upregulated in CRC tissues and cell lines, and that overexpression of HOXD-AS1 was associated with poor prognosis in patients with CRC. Furthermore, knockdown of HOXD-AS1 inhibited cell proliferation, cell invasion, epithelial-mesenchymal transition and stem cell formation in vitro, as well as tumor growth and metastasis in vivo. Mechanistically, HOXD-AS1 functioned as a competing endogenous RNA for miR-217. In conclusion, the present study demonstrated that HOXD-AS1 may promote CRC progression and metastasis by competing for miR-217. In addition, HOXD-AS1 may be considered an indicator of prognosis in patients with CRC.