CircDUSP22 Overexpression Restrains Pancreatic Cancer Development via Modulating miR-1178-3p and Downstream BNIP3

Aberrant expression of circular RNAs (circRNAs) is important in carcinogenesis, however, many differentially expressed circRNAs have not been functionally characterized. This study aimed to unveil the role of circRNA-dual specificity phosphatase 22 (circDUSP22) in pancreatic cancer (PaCa). Expression analyses of circDUSP22, miR-1178-3p and BCL2 interacting protein 3 (BNIP3) were carried out using quantitative real-time PCR (qRT-PCR) or western blotting. Cell growth was assessed by MTT, EdU and colony formation assays. Cell cycle distribution and cell apoptosis were investigated using flow cytometry assay. The assumed binding relationship between miR-1178-3p and circDUSP22 or BNIP3 was testified by dual-luciferase reporter and pull-down assays. The effect of circDUSP22 in vivo was identified by animal studies. The decreased expression of circDUSP22 was observed in PaCa samples and cells. CircDUSP22 ectopic expression in vitro blocked PaCa cell proliferation, arrested cell cycle and provoked cell apoptosis. CircDUSP22 targeted miR-1178-3p, whose expression was reinforced in PaCa. The inhibitory cell growth caused by circDUSP22 ectopic expression was reversed by miR-1178-3p enrichment. In addition, miR-1178-3p targeted BNIP3, whose expression was declined in PaCa. The inhibitory cell growth caused by circDUSP22 ectopic expression was reversed by BNIP3 knockdown. CircDUSP22 overexpression in vivo decelerated tumor growth. CircDUSP22 upregulation blocked PaCa development partly by targeting miR-1178-3p and increasing BNIP3, implying the potential implication of circDUSP22 in targeted therapy of PaCa.

Circ_0000144 acts as a miR-1178-3p decoy to promote cell malignancy and angiogenesis by increasing YWHAH expression in papillary thyroid cancer

Papillary thyroid cancer (PTC) is the most common subtype of thyroid cancer. Circular RNA hsa_circ_0000144 (circ_0000144) is related to the progression of thyroid cancer. However, the mechanism by which circ_0000144 accelerates PTC progression is still unclear. Circ_0000144 and YWHAH were upregulated in PTC tissues and cells, while miR-1178-3p had an opposite result. Circ_0000144 silencing constrained PTC cell growth in vitro and in vivo and induced apoptosis and repressed migration, invasion, and angiogenesis of PTC cells in vitro. Circ_0000144 acted as a molecular sponge for miR-1178-3p, which targeted YWHAH. MiR-1178-3p inhibitor reversed circ_0000144 silencing-mediated influence on PTC cell malignancy and angiogenesis. Furthermore, YWHAH overexpression overturned miR-1178-3p mimic-mediated influence on malignant behaviors and angiogenesis of PTC cells. Notably, circ_0000144 regulated YWHAH expression by adsorbing miR-1178-3p. Circ_0000144 promoted cell malignancy and angiogenesis by regulating the miR-1178-3p/YWHAH axis in PTC, offering a novel mechanism for the malignancy and angiogenesis of PTC cells.

Inhibition of circ_0000144 repressed malignant behaviors and angiogenesis of PTC cells in vitro.

Knockdown of circ_0000144 constrained PTC cell proliferation in vivo.

Circ_0000144 acted as a miR-1178-3p sponge.

YWHAH acted as a downstream target for miR-1178-3p.

MicroRNA-1178-3p suppresses the growth of hepatocellular carcinoma by regulating transducin (beta)-like 1 X-linked receptor 1

MicroRNAs (miRNAs) are implicated in various cancer-relevant cellular processes, including cell proliferation, migration, invasion, and angiogenesis. However, the function of miRNAs in hepatocellular cancer (HCC) has not been fully clarified. This study aimed to investigate the role of miR-1178-3p in HCC metastasis and try to reveal the potential mechanism. In the present study, we found that miR-1178-3p was down-regulated, while TBL1XR1 was up-regulated in HCC cancer tissues by bioinformatics analysis and RT-PCR. We further confirmed the connection of miR-1178-3p and TBL1XR1 using dual-luciferase reporter (DLR) assay. Moreover, gain- and loss-of-function experiments demonstrated that overexpress miR-1178-3p inhibited cell proliferation, migration, and invasion in HCC cells and reduced the xenograft tumor growth and angiogenesis by regulating the TBL1XR1/PI3K/Akt axis. Our results indicated that the novel identified miR-1178-3p functions as a tumor suppressor in HCC through regulating TBL1XR1/PI3K/Akt pathway, and these findings could be a valid molecular target for liver cancer therapy.

Circular RNA circ-ZKSCAN1 inhibits bladder cancer progression through miR-1178-3p/p21 axis and acts as a prognostic factor of recurrence

Background

Circular RNAs (circRNAs) represent a subclass of regulatory RNAs that have been shown to have significant regulatory roles in cancer progression. However, the biological functions of circRNAs in bladder cancer (BCa) are largely unknown.

Methods

Cell invasion models were established, and invasion-related circRNAs were detected by qPCR. Using above method, circ-ZKSCAN1 was picked out for further study. Circ-ZKSCAN1 expression and survival analyses were performed through qPCR. The survival curves were generated by the Kaplan-Meier method, and the log-rank test was used to assess the significance. Cell proliferation, migration and invasion were examined to investigate the function of circ-ZKSCAN1. Tumorigenesis in nude mice was assessed to determine the effect of circ-ZKSCAN1 in bladder cancer. Biotin-coupled probe pull-down assays, FISH and luciferase reporter assays were conducted to confirm the relationship between circ-ZKSCAN1 and microRNA. RNA-seq revealed different molecular changes in downstream genes.

Results

Here, we found that circ-ZKSCAN1 was downregulated in BCa tissues and cell lines. Circ-ZKSCAN1 levels were associated with survival, tumor grade, pathological T stage and tumor recurrence. Overexpressed circ-ZKSCAN1 inhibits cell proliferation, migration, invasion and metastasis in vitro and in vivo. Mechanistically, we demonstrated that circ-ZKSCAN1 upregulated p21 expression by sponging miR-1178-3p, which suppressed the aggressive biological behaviors in bladder cancer.

Conclusions

These results reveal that Circ-ZKSCAN1 acts as a tumor suppressor via a novel circ-ZKSCAN1/miR-1178-3p/p21 axis, which have the important role in the proliferation, migration and invasion ablitities of BCa cells and provide a novel perspective on circRNAs in BCa progression.

Electronic supplementary material

The online version of this article (10.1186/s12943-019-1060-9) contains supplementary material, which is available to authorized users.

MiR-1178-3p promotes the proliferation, migration and invasion of nasopharyngeal carcinoma Sune-1 cells by targeting STK4

Nasopharyngeal carcinoma (NPC) is a malignant tumor with high invasive and metastatic properties. Dysregulation of miRNAs may contribute to disease progression by targeting disease-related genes. In this study we aimed to elucidate the role and function of aberrantly expressed miRNA in NPC tumorigenesis. We found that miR-1178-3p was highly expressed in NPC tissues. Overexpression of miR-1178-3p promoted the proliferation, migration and invasion of NPC cells in vitro. In contrast, knocking down endogenous miR-1178-3p by miRNA-specific inhibitor significantly suppressed the above phenotypes. Moreover, miR- 1178-3p was shown to negatively regulate serine/threonine-protein kinase 4 (STK4), an NPC-related tumor suppressor gene, in the post-transcriptional level. Furthermore, STK4 overexpression abolished miR-1178- 3p-induced cell proliferation, migration and invasion through STK4-mediated dephosphorylation of AKT. Our results indicate that miR-1178-3p acts as an oncomiRNA in NPC by suppressing STK4 expression, and inhibition of miR-1178-3p may become a therapeutic potential for NPC.

Invasion-related circular RNA circFNDC3B inhibits bladder cancer progression through the miR-1178-3p/G3BP2/SRC/FAK axis

BACKGROUND

Increasing evidence has revealed that circular RNAs (circRNAs) play crucial roles in cancer biology. However, the role and underlying regulatory mechanisms of circFNDC3B in bladder cancer (BC) remain unknown.

METHODS

A cell invasion model was established by repeated transwell assays, and invasion-related circRNAs in BC were identified through an invasion model. The expression of circFNDC3B was detected in 82 BC tissues and cell lines by quantitative real-time PCR. Functional assays were performed to evaluate the effects of circFNDC3B on proliferation, migration and invasion in vitro-, and on tumorigenesis and metastasis in vivo. The relationship between circFNDC3B and miR-1178-3p was confirmed by fluorescence in situ hybridization, pull-down assay and luciferase reporter assay.

RESULTS

In the present study, we identified a novel circRNA (circFNDC3B) through our established BC cell invasion model. We found that circFNDC3B was dramatically downregulated in BC tissues and correlated with pathological T stage, grade, lymphatic invasion and patients' overall survival rate. Functionally, overexpression of circFNDC3B significantly inhibited proliferation, migration and invasion both in vitro and in vivo. Mechanistically, circFNDC3B could directly bind to miR-1178-3p, which targeted the 5'UTR of the oncogene G3BP2. Moreover, circFNDC3B acted as a miR-1178-3p sponge to suppress G3BP2, thereby inhibiting the downstream SRC/FAK signaling pathway.

CONCLUSIONS

CircFNDC3B may serve as a novel tumor suppressive factor and potential target for new therapies in human BC.