HOX antisense lincRNA HOXA-AS2 is an apoptosis repressor in all<i>Trans</i>retinoic acid treated NB4 promyelocytic leukemia cells

Background/Aims: Thyroid cancer is one of the most prevalent endocrine tumors. The present study examined the effects of lncRNA HOXA cluster antisense RNA2 (HOXA-AS2) on the progression of papillary thyroid cancer (PTC), and explored the underlying molecular mechanisms. Methods: Quantitative real-time PCR was used to detect HOXA-AS2, miR-520c-3p and S100 calcium-binding protein A4 (S100A4) expression. Furthermore, the effects of HOXA-AS2 silencing and overexpression on cell proliferation, migration, and invasion were assessed in PTC in vitro by CCK8 and transwell assay. Furthermore, bioinformatics online programs predicted and luciferase reporter assay were used to validate the association of HOXA-AS2 and miR-520c-3p in PTC. Results: We observed that HOXA-AS2 was up-regulated in PTC tissues. In vitro experiments revealed that HOXA-AS2 knockdown significantly inhibited cell growth in PTC in vitro and in vivo. Further functional assays indicated that HOXA-AS2 significantly promoted PTC 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 PTC cells. MiR-520c-3p was down-regulated in PTC tissues, and S100A4 was predicted as a downstream target of miR-520c-3p, which was confirmed by luciferase reporter assay. Conclusion: In summary, our results suggested that the HOXA-AS2/miR-520c-3p/S100A4 axis may play an important role in the regulation of PTC progression, which provides us with new insights into understanding the PTC.

Section: Introductionmentioning

confidence: 99%

Long Noncoding RNA HOXA-AS2 Promotes Papillary Thyroid Cancer Progression by Regulating miR-520c-3p/S100A4 Pathway

Xia

Chen

Jiang

et al. 2018

“…Moreover, recent evidence has implicated the involvement of long non-coding RNAs (lncRNAs) in several of the steps leading to glioma development [10, 11]. The lncRNA HOXA cluster antisense RNA 2 (HOXA-AS2) was first reported to be an apoptosis suppressor in NB4 promyelocytic leukemia cells treated with all-trans retinoic acid [12]. Subsequent studies showed that HOXA-AS2 is aberrantly expressed in several human cancers and functions as an oncogene [13, 14].…”

Section: Introductionmentioning

confidence: 99%

Long Non-Coding RNA HOXA-AS2 Regulates Malignant Glioma Behaviors and Vasculogenic Mimicry Formation via the MiR-373/EGFR Axis

Gao

Liu

et al. 2017

Background/Aims: Vasculogenic mimicry (VM) has been reported to be a novel glioma neovascularization process. Anti-VM therapy provides new insight into glioma clinical management. In this study, we revealed the role of the long non-coding RNA HOXA cluster antisense RNA 2 (HOXA-AS2) in malignant glioma behaviors and VM formation. Methods: Quantitative real-time PCR was performed to determine the expression levels of HOXA-AS2 in glioma samples and glioblastoma cell lines. CD34-periodic acid-Schiff dual-staining was performed to assess VM in glioma samples. CCK-8, transwell, and Matrigel tube formation assays were performed to measure the effects of HOXA-AS2 knockdown on cell viability, migration, invasion, and VM tube formation, respectively. RNA immunoprecipitation, dual-luciferase reporter and Western blot assays were performed to explore the molecular mechanisms underlying the functions of HOXS-AS2 in glioblastoma cells. A nude mouse xenograft model was used to investigate the role of HOXA-AS2 in xenograft glioma growth and VM density. Student’s t-tests, one-way ANOVAs followed by Bonferroni posthoc tests, and chi-square tests were used for the statistical analyses. Results: HOXA-AS2 was upregulated in glioma samples and cell lines and was positively correlated with VM. HOXA-AS2 knockdown attenuated cell viability, migration, invasion, and VM formation in glioma cells and inhibited the expression of vascular endothelial-cadherin (VE-cadherin), as well as the expression and activity of matrix metalloproteinase matrix metalloproteinase (MMP)-2 and MMP-9. miR-373 was downregulated in glioma samples and cell lines and suppressed malignancy in glioblastoma cells. HOXA-AS2 bound to miR-373 and negatively regulated its expression. Epidermal growth factor receptor (EGFR), a target of miR-373, increased the expression levels of VE-cadherin, as well as the expression and activity levels of MMP-2 and MMP-9, via activating phosphatidylinositol 3-kinase/serine/threonine kinase pathways. HOXA-AS2 knockdown combined with miR-373 overexpression yielded optimal tumor suppressive effects and the lowest VM density in vivo. Conclusion: HOXA-AS2 knockdown inhibited malignant glioma behaviors and VM formation via the miR-373/EGFR axis.

“…Consisted with previous findings, HOXA-AS2 was upregulated in some kinds of tumor cells, including acute promyelocytic leukemia and gastric cancer [19,20]. But little is known about the role of HOXA-AS2 in HCC progression.…”

Section: Discussionmentioning

confidence: 99%

“…LncRNA HOTAIR functions as an oncogene and high expression level of HOTAIR is correlated with metastases and survival in many cancers [14][15][16][17][18]. HOXA-AS2, a long non-coding RNA located between the HOXA3 and HOXA4 genes in the HOXA cluster, has been characterized as an oncogene in acute promyelocytic leukemia and gastric cancer, and knockdown of HOXA-AS2 inhibited cell proliferation and induced cell apoptosis [19,20]. However, whether HOXA-AS2 is involved in the progression of HCC is ill-defined and the molecular mechanisms remain to be fully elucidated.…”

Section: Introductionmentioning

confidence: 99%

HOX Antisense lincRNA HOXA-AS2 Promotes Tumorigenesis of Hepatocellular Carcinoma

Wang

Yang

Deng

et al. 2016

Background: Recent studies reveal that long non-coding RNAs (LncRNAs) play critical roles in the proliferation and migration of human cancer. Previous report has shown that LncRNA HOXA-AS2 was involved in carcinoma processes. However, the expression and biological function of HOXA-AS2 in hepatocellular carcinoma (HCC) are poorly understood. Methods: Quantitative real-time PCR (qRT-PCR) was performed to detect the expression of HOXA-AS2 in HCC tissues and cell lines. The relation between lncRNA HOXA-AS2 expression and clinicopathological characteristics was assessed by chi-square test. The prognosis was analyzed using Kaplan-Meier method, and compared differences between the two groups by log-rank test. The biological function of HOXA-AS2 on HCC cells were determined both in vitro and in vivo. Results: In the present study, we found that HOXA-AS2 expression was increased in HCC tissues and adjacent normal tissues and high HOXA-AS2 expression was associated with bigger tumor size, advanced tumor stage, and shorter survival time. Knockdown of HOXA-AS2 significantly inhibited HCC cell proliferation and invasion and resulted in an increase of apoptosis. Furthermore, inhibition of HOXA-AS2 in HCC cells significantly repressed tumorigenicity in nude mice. Conclusion: Our results indicated that the inhibition of HOXA-AS2 in HCC cells significantly inhibited cell proliferation in vitro and in vivo, which might provide a potential possibility for targeted therapy of HCC.