PAX3 Promotes Proliferation of Human Glioma Cells by WNT/β-Catenin Signaling Pathways

DLGAP5 knockdown inactivates the Wnt/β-catenin signal to repress endometrial cancer cell malignant activities

Human discs large-associated protein 5 (DLGAP5), a microtubule-associated protein, has been reported to be upregulated in several tumors. However, the role of DLGAP5 in endometrial cancer (EC) progression and the related underlying mechanism were still unknown. A bioinformatics analysis was performed to analyze the expression and prognostic significance of DLGAP5 in EC tissues using TCGA, CPTAC, Human Protein Atlas, and GSE63678 databases, UALCAN web tool, and the Kaplan-Meier plotter. Effects of DLGAP on EC cell malignant properties were evaluated by CCK-8, flow cytometry analysis, TUNEL assay, caspase-3 activity assay, and Transwell invasion assay. The expression of DLGAP5, Wnt3, c-Myc, Ki67, and cleaved caspase-3 was detected by western blot analysis. DLGAP5 was highly expressed and correlated with poor prognosis in EC patients. DLGAP5 knockdown inhibited proliferation and invasion, triggered apoptosis, and increased caspase-3 activity in EC cells. Additionally, DLGAP5 knockdown inactivated the Wnt/β-catenin signaling pathway in EC cells. Moreover, β-catenin overexpression abolished the effects of DLGAP5 knockdown on the malignant phenotypes of EC cells. DLGAP5 silencing suppressed the malignant properties in EC cells by inactivating the Wnt/β-catenin pathway.

A case report of melanotic neuroectodermal tumor of infancy complicated with congenital heart disease and hypothyroidism

To the best of our knowledge, thus far there are no reported cases of melanotic neuroectodermal tumor of infancy (MNTI) with multiple complications. In this case report, we describe the clinical phenotype of MNTI in a 9-month-old female infant associated with tetralogy of Fallot (TOF), a congenital heart defect, and congenital hypothyroidism (CH). Our study showed that the growth of MNTI was delayed by a lower dosage of levothyroxine (L-T4) that was prescribed to treat CH because of the presence of TOF, a severe congenital heart disease. However, the standardized dosage of L-T4 improved thyroid function but stimulated the rapid growth of MNTI. Our report demonstrated that treatment with L-T4 affects the progression of MNTI. Our findings demonstrated the role of thyroid hormone in MNTI growth and progression. Furthermore, our study suggested that the treatment of co-morbidities in children with MNTI requires careful consideration of their effects on the growth and progression of MNTI.

Green Synthesized Bismuth Oxide Nanoparticles Using Aqueous Rhizome Extract of Curcuma longa Mitigate the Proliferation of Human U87 Glioblastoma Cells by Regulation of the Wnt/β-Catenin Signaling Pathway

The low biocompatibility of inorganic nanoparticles (NPs) is a main concern in their wide applications in the biomedical field. Therefore, the green synthesis of NPs from plant extracts can provide safe NPs for biomedical applications. The present study was aimed to assess the anticancer activity of bismuth oxide (Bi2O3) NPs fabricated using aqueous plant extracts from the rhizome of Curcuma longa (C. longa). Characterization of green Bi2O3 NPs was done using TEM, DLS, and X-ray diffraction analyses. Selective anticancer activity of green Bi2O3 NPs against human glioblastoma (U87) cells was assessed using MTT, GSH, MDA, ROS, apoptosis, and caspase-3 assays. Also, qPCR analysis was done to explore the expression of β-catenin, cyclin D1, and c-myc at mRNA level as the important genes of the Wnt/β-catenin signaling pathway. The results showed that the green Bi2O3 NPs have a crystalline nature with a size of around 30 nm with good colloidal stability attributed to potential bio-fabrication of Bi2O3 NPs. Cellular study indicated that green Bi2O3 NPs triggered selective anticancer activity against U87 cells through reduction of GSH level and increase of MDA level, ROS level, Annexin+ cells, and caspase-3 activity. Also, it was found that IC50 concentration of biosynthesized Bi2O3 NPs (20 μg/mL) resulted in a significant downregulation in the expression of β-catenin, cyclin D1, and c-myc genes involved in the Wnt/β-catenin signaling pathway. This study concludes that green Bi2O3 NPs bio-fabricated from rhizome of C. longa show potential selective anticancer activity.

LncRNA ANCR promotes glioma cells invasion, migration, proliferation and inhibits apoptosis via interacting with EZH2 and repressing PTEN expression

Recently, the role of long noncoding RNA (lncRNA) has been identified in human diseases, and we aim to explore the role of lncRNA antidifferentiation noncoding RNA (ANCR) in glioma. Expression of lncRNA ANCR, enhancer of zeste homolog 2 (EZH2), and phosphatase and tensin homolog (PTEN) in glioma tissues and cells was determined by RT-PCR or western blot assay. The correlation between expression of ANCR, EZH2, and PTEN in glioma tissues was analyzed using Pearson test. The apoptosis, transwell invasion, migration, colony formation, and proliferation assays were conducted to evaluate the influences of lncRNA ANCR depletion, EZH2 reduction, or PTEN elevation on the cell biology of glioma cells. The relationships between ANCR and EZH2, and between EZH2 and PTEN were confirmed through RIP, RNA pull-down, and chromatin immunoprecipitation assays. Our results indicated that ANCR and EZH2 were upregulated and PTEN was downregulated in glioma tissues and cell lines. ANCR expression was positively related to EZH2 expression, while PTEN expression was negatively related to ANCR/EZH2 expression. Inhibited ANCR, reduced EZH2, or elevated PTEN could reduce the ability of invasion, migration, and proliferation, and promote apoptosis of glioma cells. PTEN overexpression or EZH2 inhibition reversed the promotive role of ANCR upregulation in glioma cell growth and metastasis. Mechanistically, PTEN was upregulated in ANCR knockdown glioma cells. EZH2 interacted with ANCR in glioma cells. In conclusion, we have found that restrained ANCR could repress invasion, migration, and proliferation, as well as promote apoptosis of glioma cells through interacting with EZH2 and regulating the expression of PTEN, offering an effective therapeutic target for patients with glioma.

miR-299-3p suppresses cell progression and induces apoptosis by downregulating PAX3 in gastric cancer

Gastric cancer (GC) is ranked the fourth leading cause of cancer-related death, with an over 75% mortality rate worldwide. In recent years, miR-299-3p has been identified as a biomarker in multiple cancers, such as acute promyelocytic leukemia, thyroid cancer, and lung cancer. However, the regulatory mechanism of miR-299-3p in GC cell progression is still largely unclear. Cell viability and apoptosis tests were performed by CCK8 and flow cytometry assay, respectively. Transwell assay was recruited to examine cell invasion ability. The interaction between miR-299-3p and PAX3 was determined by the luciferase reporter system. PAX3 protein level was evaluated by western blot assay. The expression of miR-299-3p was downregulated in GC tissues and cell lines (MKN-45, AGS, and MGC-803) compared with the normal tissues and cells. Besides, overexpression of miR-299-3p significantly suppressed proliferation and invasion and promoted apoptosis in GC. Next, we clarified that PAX3 expression was regulated by miR-299-3p using a luciferase reporter system, qRT-PCR, and western blot assay. Additionally, downregulation of PAX3 repressed GC cell progression. The rescue experiments indicated that restoration of PAX3 inversed miR-299-3p-mediated inhibition on cell proliferation and invasion. miR-299-3p suppresses cell proliferation and invasion as well as induces apoptosis by regulating PAX3 expression in GC, representing desirable biomarkers for GC diagnosis and therapy.

Down-Regulation of miR-181a-5p Prevents Cerebral Ischemic Injury by Upregulating En2 and Activating Wnt/β-catenin Pathway

PURPOSE

Cerebral ischemic injury contributes to severe dysfunction of the brain, which triggers extremely high mortality and disability. The role of microRNA (miR)-181a-5p is documented in cerebral ischemic injury. Therefore, this study intended to further figure out the mechanism of miR-181a-5p in cerebral ischemic injury.

METHODS

miR-181a-5p expression in middle cerebral artery occlusion (MCAO) mouse model, oxygen-glucose-deprivation/reoxygenation (OGD/R) N2a cell model, and serum from acute ischemic injury (ACI) patients was evaluated using reverse transcription quantitative polymerase chain reaction (RT-qPCR). Gain- and loss-of-function assays were implemented in MCAO mice and OGD/R-induced N2a cells. In mice, the cerebral infarction area was assessed with 2,3,5-triphenyltetrazolium chloride staining, the number of damaged neurons by Nissl staining, and apoptosis by TdT-mediated dUTP-biotin nick end-labeling staining. Moreover, N2a cell apoptosis and proliferation were determined with flow cytometry or 5-ethynyl-2'-deoxyuridine staining, respectively. The expression of En2 and Wnt/β-catenin pathway-related factors was determined with RT-qPCR and Western blot analysis. The targeting relationship between miR-181a-5p and En2 was evaluated by dual luciferase reporter gene assay.

RESULTS

miR-181a-5p was highly expressed in serum of ACI patients, MCAO mice, and OGD/R-induced N2a cells. En2, lowly expressed in MCAO mice, was targeted by miR-181a-5p, and miR-181a-5p down-regulation activated the Wnt/β-catenin pathway. Furthermore, miR-181a-5p inhibition or En2 overexpression reduced cerebral infarction area, the number of damaged neurons, and apoptosis in MCAO mice, and also diminished apoptosis and accelerated proliferation of OGD/R-induced N2a cells.

CONCLUSION

miR-181a-5p suppression activated Wnt/β-catenin pathway and sequentially attenuated cerebral ischemic injury by targeting En2.

Farnesoid X receptor antagonizes Wnt/β-catenin signaling in colorectal tumorigenesis

Farnesoid X receptor (FXR, encoded by NR1H4), a critical regulator of bile acid homeostasis, is widely implicated in human tumorigenesis. However, the functional role of FXR in colorectal cancer (CRC) and the precise molecular mechanism remain unclear. In this study, we demonstrated that FXR expression was downregulated in colon cancer tissues and decreased expression of FXR predicted a poor prognosis. Knockdown of FXR promoted colon cancer cell growth and invasion in vitro, and facilitated xenograft tumor formation and distant metastasis in vivo, whereas ectopic expression of FXR had the reserved change. Mechanistic studies indicated that FXR exerted its tumor suppressor functions by antagonizing Wnt/β-catenin signaling. Furthermore, we identified an FXR/β-catenin interaction in colon cancer cells. The FXR/β-catenin interaction impaired β-catenin/TCF4 complex formation. In addition, our study suggested a reciprocal relationship between FXR and β-catenin, since loss of β-catenin increased the transcriptional activation of SHP by FXR. Altogether, these data indicated that FXR functions a tumor-suppressor role in CRC by antagonizing Wnt/β-catenin signaling.

Asymmetric Expression of Wnt/B-catenin Pathway in AIS: Primary or Secondary to the Curve?

STUDY DESIGN

A prospective case-control study.

OBJECTIVES

To investigate whether the asymmetric changes are primary or secondary to spinal deformity.

SUMMARY OF BACKGROUND DATA

Previous study reported significantly decreased expression of Wnt/B-catenin pathway in adolescent idiopathic scoliosis (AIS) patients. To date, there is a lack of study investigating the relationship between differentially expressed Wnt/B-catenin pathway and the onset of the curve.

METHODS

Paraspinal muscles were collected from 40 female AIS patients and 20 age-matched congenital scoliosis (CS) patients. For CS patients, the samples were collected from the concave side and the convex side at the apical region. For AIS patients, the samples were collected from the proximal bilateral sides of the spine in addition to the apical region. qPCR and western blot were used to determine the expression of LBX1, B-catenin, and PAX3, all of which are regulated by the Wnt/B-catenin pathway. The relative mRNA expression level between the concave and the convex side was performed with the Student t test. Pearson correlation analysis was used to determine the relationship between gene expression and the curve magnitude.

RESULTS

AIS patients were found to have remarkably lower mRNA and protein expression of B-catenin, LBX1, and PAX3 in the concave side than in the convex side at the apical region. By contrast, at the proximal region, the mRNA expression of these three genes was comparable. Moreover, no significant difference regarding mRNA expression was found between the concave side and the convex side of CS patients. There was no remarkable correlation between the mRNA expression of the three genes and Cobb angle.

CONCLUSION

There exists remar kably asymmetric expression of Wnt/B-catenin pathway at the apical region of AIS, which however was comparable at the apical region of CS patients. Further investigation of Wnt/B-catenin signaling pathway may help reveal the etiology of AIS in future study.

LEVEL OF EVIDENCE

4.

Modulating lncRNA SNHG15/CDK6/miR-627 circuit by palbociclib, overcomes temozolomide resistance and reduces M2-polarization of glioma associated microglia in glioblastoma multiforme

Background

Accumulating evidence demonstrates the oncogenic roles of lncRNA (long non-coding RNA) molecules in a wide variety of cancer types including glioma. Equally important, However, tumorigenic functions of lncRNA in glioma remain largely unclear. A recent study suggested lncRNA SNHG15 played a role for regulating angiogenesis in glioma but its role in the tumor microenvironment (TME) was not investigated.

Methods

First, we showed that SNHG15 was upregulated in GBM cells and associated with a poor prognosis for the patients of GBM using public databases. Next, we collected temozolomide sensitive (TMZ-S) and resistant (TMZ-R) clinical samples and demonstrated that co-culturing TMZ-R cells with HMC3 (microglial) cells promoted M2-polarization of HMC3 and the secretion of pro-GBM cytokines TGF-β and IL-6.

Results

Comparative qPCR analysis of TMZ-S and TMZ-R cells showed that a significantly higher level of SNHG15, coincidental with a higher level of Sox2, β-catenin, EGFR, and CDK6 in TMZ-R cells. Subsequently, using bioinformatics tool, a potential mechanistic route for SNHG15 to promote GBM tumorigenesis was by inhibiting tumor suppressor, miR-627-5p which leads to activation of CDK6. Gene-silencing technique was employed to demonstrate that suppression of SNHG15 indeed led to the suppression of GBM tumorigenesis, accompanied by an increase miR-627-5p and decreased its two oncogenic targets, CDK6 and SOX-2. In addition, SNHG15-silenced TMZ-R cells became significantly sensitive towards TMZ treatment and less capable of promoting M2-phenotype in the HMC3 microglial cells. We then evaluated the potential anti-GBM activity of CDK6 inhibitor, palbociclib, using TMZ-R PDX mouse models. Palbociclib treatment significantly reduced tumorigenesis in TMZ-R/HMC3 bearing mice and SNHG15 and CDK6 expression was significantly reduced while miR-627-5p level was increased. Additionally, palbociclib treatment appeared to overcome TMZ resistance as well as reduced M2 markers in HMC3 cells.

Conclusion

Together, we provided evidence supporting the usage of CDK6 inhibitor for TMZ-resistant GBM cases. Further investigation is warranted for the consideration of clinical trials.

Graphical abstract

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1371-0) contains supplementary material, which is available to authorized users.

Emerging Pathogenic and Prognostic Significance of Paired Box 3 (PAX3) Protein in Adult Gliomas

Gliomas present the most common type of brain tumors in adults, characterized by high morbidity and mortality. In search of potential molecular targets, members of paired box (PAX) family have been found expressed in neural crest cells, regulating their proliferation, apoptosis, migration and differentiation. Recently, PAX3 overexpression has been implicated in glioma tumorigenesis by enhancing proliferation, increasing invasiveness and inducing resistance to apoptosis of glioma cells, while maintaining brain glioma stem cells (BGSCs) stemness. Although the oncogenic potential of PAX3 in gliomas is still under investigation, experimental evidence suggests that PAX3 function is mainly mediated through the canonical and non-canonical Wnt signaling pathway as well as through its interaction with GFAP and p53 proteins. In addition, PAX3 may contribute to the chemoresistance of glioma cells and modulates the effectiveness of novel experimental therapies. Further evidence indicates that PAX3 may represent a novel diagnostic and prognostic biomarker for gliomas, facilitating personalized treatment. This review addresses the emerging role of PAX3 in glioma diagnosis, prognosis and treatment, aiming to shed more light on the underlying molecular mechanisms that could lead to more effective treatment approaches.