HOXA-AS2 Promotes Proliferation and Induces Epithelial-Mesenchymal Transition via the miR-520c-3p/GPC3 Axis in Hepatocellular Carcinoma

Abstract

Background/Aims: Previous studies have demonstrated that long non-coding RNAs (lncRNAs) may play critical roles in cancer biology, including Hepatocellular carcinoma (HCC). The HOXA cluster antisense RNA2 (HOXA-AS2) lncRNA plays an important role in carcinogenesis, however, the underlying role of HOXA-AS2 in HCC remains unknown. The present study examined the effects of HOXA-AS2 on the progression of HCC, and explored the underlying molecular mechanisms. Methods: Quantitative real-time PCR was used to detect HOXA-AS2 expression in HCC tissues and cell lines. Furthermore, the effects of HOXA-AS2 silencing and overexpression on cell proliferation, cell cycle, apoptosis, migration, and invasion were assessed in HCC in vitro and in vivo. Furthermore, bioinformatics online programs predicted and luciferase reporter assay were used to validate the association of HOXA-AS2 and miR-520c-3p in HCC cells. Results: We observed that HOXA-AS2 was up-regulated in HCC tissues and cell lines. In vitro experiments revealed that HOXA-AS2 knockdown significantly inhibited HCC cells proliferation by causing G1 arrest and promoting apoptosis, whereas HOXA-AS2 overexpression promoted cell growth. Further functional assays indicated that HOXA-AS2 significantly promoted HCC cell migration and invasion by promoting EMT. Bioinformatics online programs predicted that HOXA-AS2 sponge miR-520c-3p at 3’-UTR with complementary binding sites, which was validated using luciferase reporter assay. HOXA-AS2 could negatively regulate the expression of miR-520c-3p in HCC cells. MiR-520c-3p was down-regulated and inversely correlated with HOXA-AS2 expression in HCC tissues. miR-520c-3p suppressed cell proliferation, invasion and migration in HCC cells, and enforced expression of miR-520c-3p attenuated the oncogenic effects of HOXA-AS2 in HCC cells. By bioinformatic analysis and dual-luciferase reporter assay, we found that miR-223-3p directly targeted the 3’-untranslated region (UTR) of Glypican-3 (GPC3), one of the key players in HCC. GPC3 was up-regulated in HCC tissues, and was negatively correlated with miR-520c-3p expression and positively correlated with HOXA-AS2 expression. Conclusion: In summary, our results suggested that the HOXA-AS2/miR-520c-3p/GPC3 axis may play an important role in the regulation of PTC progression, which could serve as a biomarker and therapeutic target for HCC.

<p>LINC00339 promotes growth and invasiveness of hepatocellular carcinoma by the miR-1182/SKA1 pathway</p>

“…10 lncRNA HOXA-AS2 upregulation in HCC enhances tumor growth and induces epithelial-mesenchymal transition. 11 Thus, because of the significant importance of lncRNAs, it is essential to explore the correlation between lncRNA and HCC progression.…”

Long non-coding RNA HOXA-AS2 may serve as a new therapeutic target and promising prognostic market for most of cancers

“…In the end, 12 articles with a total of 796 patients (Table 1) were included in this study. There were 8 types of cancer in these 12 literatures, including 2 cases of lung cancer [17,18], 2 of thyroid cancer [19,20], 1 of bladder cancer [21], 1 of breast cancer [22], 1 of gastric cancer [23], 2 of colorectal cancer [9,10], 1 of osteosarcoma [24] and 2 cases of liver cancer [14,25]. All the 12 articles come from China (Table 1).…”

“…Through the lnCAR database, we found that HOXA-AS2 can regulate the expression of mRNA through miR-372-3p, miR-373-3p, miR-302a-3p, miR-519d-3p, miR-106b-5p, miR-520b, miR-302e, miR-520e, miR-106a-5p, miR-302d-3p, miR-302c-3p, MiR-302b-3p, miR-20a-5p, miR-520d-3p, miR-17-5p, miR-93-5p, miR-20b-5p, miR-520c-3p and miR-520a-3p, and further participate in the occurrence and development of tumor. At present, studies have confirmed that long-chain non-coding RNAHOXA-AS2 can take part in the progression of AML, thyroid papillary carcinoma, HCC and breast cancer throuh target regulating of miR-520c-3p [12,14,19,22]. In addition, HOXA-AS2 can promote the malignant progression of non-small cell lung cancer, thyroid papillary carcinoma and liver cancer through miRNA-216a-5p, miR-520a-3p, miR-15a-5p and miR-125b [17,18,20,21].…”

“…In addition, HOXA-AS2 could leads to migration and invasion of HCC cells by promoting the change of EMT characteristics. These results suggest that HOXA-AS2 plays an important role in the progression of cancer and can be used as a new biomarker and target for tumor therapy [14]. However, the potential clinical value of HOXA-AS2 in the prognosis of tumors is still controversial.…”

“…And further studies found that HOXA-AS2 could negatively regulated the apoptosis of NB4 cells induced by ATRA [8]. In recent years, it had been reported that HOXA-AS2 was abnormally expressed in colorectal cancer [9][10][11], acute lymphoblastic leukemia (ALL) and hepatocellular carcinoma [12][13][14], and was involved in the occurrence and development of tumor. The expression of HOXA-AS2 in colorectal cancer (CRC) was increased and high expression of HOXA-AS2 indicated larger tumor size, later stage, and worse prognosis of patients [9,10].…”