CircHIPK2 promotes proliferation of nasopharyngeal carcinoma by down-regulating HIPK2

Abstract

Background: Circular RNAs (circRNAs) are a new family of endogenous non-coding RNAs generated by a covalently closed loop, and a mounting body of data suggests they control gene expression. While the circRNA-homeodomain-interacting protein kinase-2 (circHIPK2) is generated from the homeodomaininteracting protein kinase 2 (HIPK2) gene, the function of circHIPK2 in nasopharyngeal cancer (NPC) along with the responsible mechanisms are still unclear.Methods: RNA-sequencing data was utilized to determine the differentially expressed circRNAs, and circHIPK2 was established as a novel prospective circRNA. The expressions of circRNAs along with messenger RNAs (mRNAs) in NPC tissues and cells was assessed via quantitative real-time polymerase chain reaction (qRT-PCR), and the transfection of NPC cells with plasmids in vitro and in vivo was adopted to explore the effects of circHIPK2 in NPC. Western blotting was adopted to assess the expressions of HIPK2 and β-catenin, while Cell Counting Kit (CCK)-8 assay coupled with colony-forming assay were utilized to assess the biological functions. The expression of nuclear and cytoplasmic HIPK2 was detected via nucleocytoplasmic separation assay.Results: Herein, we established that circHIPK2 was upregulated in NPC tissues. Over-expression of circHIPK2 promoted cell proliferation in vitro and in vivo, and further studies revealed it inhibited the protein level of HIPK2 in a post-transcriptional pattern, decreasing β-catenin expression and suppressing the proliferation of NPC.Conclusions: Our findings demonstrated elevated circHIPK2 facilitated the cell proliferation of NPC cells via the circHIPK2/HIPK2 axis, suggesting circHIPK2 might be an oncogene to promote the process of NPC and could be a novel treatment target for its management.

Curcumin inhibits colon cancer malignant progression and promotes T cell killing by regulating miR‐206 expression

“…miRNAs could possibly be used as novel biomarkers for prognosis and treatment of human cancers, their effect and regulatory mechanisms in human cancers having been a focus for research in recent years. It has been shown that miR‐206 has a cancer‐inhibiting effect in human malignancies (Kondo et al, 2008; Taulli et al, 2009; Vickers et al, 2012; Wang et al, 2011; Zhang et al, 2011). miR‐206 can regulate tumor immune escape by regulating the expression of cytokines (Haas et al, 2011), and it can hamper activation of the JAK/STAT signaling pathway by down‐regulation of ANXA1 expression (Zhao, Shen, et al, 2019).…”

“…Curcumin was found to affect tumor development by regulating miRNA expression. miR‐206 is an important miRNA affecting tumor development, and its expression is down‐regulated in human cancers such as breast cancer (Kondo et al, 2008), rhabdomyosarcoma (Taulli et al, 2009), lung cancer (Wang et al, 2011), laryngeal cancer (Zhang et al, 2011), and colorectal cancer (Vickers et al, 2012). For example, it impedes the proliferation of gastric cancer cells by inhibiting cyclin D2 (Zhang et al, 2013).…”