scholarly journals KDM6B promotes oncogenic CDK4/6-pRB-E2F pathway via maintaining enhancer activation in high-risk neuroblastoma

2020 ◽  
Author(s):  
Alexandra D’Oto ◽  
Jie Fang ◽  
Hongjian Jin ◽  
Beisi Xu ◽  
Shivendra Singh ◽  
...  

ABSTRACTThe H3K27me2/me3 histone demethylase KDM6B is over-expressed in neuroblastoma and essential to neuroblastoma cell survival. While the KDM6B inhibitor, GSK-J4, has shown activity in in vitro and in vivo preclinical models, the mechanism of action remains poorly defined. We demonstrate that genetic and pharmacologic inhibition of KDM6B downregulate the pRB-E2F transcriptome and MYCN expression. Chemical genetics analyses show that a high E2F transcriptome is positively correlated with sensitivity of cancer cells to the KDM6 inhibitor GSK-J4. Mechanistically, inhibition of KDM6B activity reduces the chromatin accessibility of E2F target genes and MYCN. GSK-J4 alters distribution of H3K27me3 and broadly represses the enhancer mark H3K4me1, which may consequently disrupt the long-range chromatin interaction of E2F target genes. KDM6B inhibition phenocopies the transcriptome induced by the specific CDK4/6 inhibitor palbociclib. Overexpression of CDK4/6 or Rb1 knockout not only confers neuroblastoma cell resistance to palbociclib but also to GSK-J4. A gene signature targeted by KDM6B inhibition is associated with poor survival of patients with neuroblastoma regardless of the MYCN status. These data indicate that KDM6B activity promotes an oncogenic CDK4/6-pRB-E2F pathway in neuroblastoma cells via H3K27me3-dependent enhancer-promoter interactions, providing a rationale to target KDM6B for high-risk neuroblastoma.

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Alexandra D’Oto ◽  
Jie Fang ◽  
Hongjian Jin ◽  
Beisi Xu ◽  
Shivendra Singh ◽  
...  

AbstractThe H3K27me2/me3 histone demethylase KDM6B is essential to neuroblastoma cell survival. However, the mechanism of KDM6B action remains poorly defined. We demonstrate that inhibition of KDM6B activity 1) reduces the chromatin accessibility of E2F target genes and MYCN, 2) selectively leads to an increase of H3K27me3 but a decrease of the enhancer mark H3K4me1 at the CTCF and BORIS binding sites, which may, consequently, disrupt the long-range chromatin interaction of MYCN and E2F target genes, and 3) phenocopies the transcriptome induced by the specific CDK4/6 inhibitor palbociclib. Overexpression of CDK4/6 or Rb1 knockout confers neuroblastoma cell resistance to both palbociclib and the KDM6 inhibitor GSK-J4. These data indicate that KDM6B promotes an oncogenic CDK4/6-pRB-E2F pathway in neuroblastoma cells via H3K27me3-dependent enhancer-promoter interactions, providing a rationale to target KDM6B for high-risk neuroblastoma.


2020 ◽  
Author(s):  
Amparo López-Carrasco ◽  
Susana Martín-Vañó ◽  
Rebeca Burgos-Panadero ◽  
Ezequiel Monferrer ◽  
Ana P Berbegall ◽  
...  

Abstract Background Increased tissue stiffness is a common feature of malignant solid tumors, often associated with metastasis and poor patient outcomes. Vitronectin, as an extracellular matrix anchorage glycoprotein related to a stiff matrix, is present in a particularly increased quantity and specific distribution in high-risk neuroblastoma. Furthermore, as cells can sense and transform the proprieties of the extracellular matrix into chemical signals through mechanotransduction, genotypic changes related to stiffness are possible. Methods We have applied high density SNPa and NGS techniques to in vivo and in vitro models (orthotropic xenograft vitronectin knock-out mice and 3D bioprinted hydrogels with different stiffness) using two representative neuroblastoma cell lines (the MYCN amplified SK-N-BE(2) and the ALK mutated SH-SY5Y), to discern how tumor genomics patterns and clonal heterogeneity of both cell lines are affected. Results We describe a remarkable subclonal selection of some genomic aberrations in SK-N-BE(2) cells grown in knock-out vitronectin xenograft mice that also emerged when cultured for long times in stiff hydrogels. Specially, we detected an enlarged subclonal cell population with chromosome 9 aberrations in both models. Similar abnormalities were found in human high-risk neuroblastoma with MYCN amplification. Genomics of the SH-SY5Y cell line remained stable when cultured in both models. Conclusions Focus on heterogeneous intratumor segmental chromosome aberrations and mutations, as a mirror image of tumor microenvironment, is a vital area of future research.


2021 ◽  
Vol 9 (10) ◽  
pp. e003163
Author(s):  
Mitchell Evers ◽  
Marjolein Stip ◽  
Kaylee Keller ◽  
Hanneke Willemen ◽  
Maaike Nederend ◽  
...  

BackgroundThe addition of monoclonal antibody therapy against GD2 to the treatment of high-risk neuroblastoma led to improved responses in patients. Nevertheless, administration of GD2 antibodies against neuroblastoma is associated with therapy-limiting neuropathic pain. This severe pain is evoked at least partially through complement activation on GD2-expressing sensory neurons.MethodsTo reduce pain while maintaining antitumor activity, we have reformatted the approved GD2 antibody ch14.18 into the IgA1 isotype. This novel reformatted IgA is unable to activate the complement system but efficiently activates leukocytes through the FcαRI (CD89).ResultsIgA GD2 did not activate the complement system in vitro nor induced pain in mice. Importantly, neutrophil-mediated killing of neuroblastoma cells is enhanced with IgA in comparison to IgG, resulting in efficient tumoricidal capacity of the antibody in vitro and in vivo.ConclusionsOur results indicate that employing IgA GD2 as a novel isotype has two major benefits: it halts antibody-induced excruciating pain and improves neutrophil-mediated lysis of neuroblastoma. Thus, we postulate that patients with high-risk neuroblastoma would strongly benefit from IgA GD2 therapy.


2020 ◽  
Vol 23 (3) ◽  
pp. 165-177 ◽  
Author(s):  
Bhaskar Roy ◽  
Michael Dunbar ◽  
Juhee Agrawal ◽  
Lauren Allen ◽  
Yogesh Dwivedi

Abstract Background Recent studies suggest that microRNAs (miRNAs) can participate in depression pathogenesis by altering a host of genes that are critical in corticolimbic functioning. The present study focuses on examining whether alterations in the miRNA network in the amygdala are associated with susceptibility or resiliency to develop depression-like behavior in rats. Methods Amygdala-specific altered miRNA transcriptomics were determined in a rat depression model following next-generation sequencing method. Target prediction analyses (cis- and trans) and qPCR-based assays were performed to decipher the functional role of altered miRNAs. miRNA-specific target interaction was determined using in vitro transfection assay in neuroblastoma cell line. miRNA-specific findings from the rat in vivo model were further replicated in postmortem amygdala of major depressive disorder (MDD) subjects. Results Changes in miRNome identified 17 significantly upregulated and 8 significantly downregulated miRNAs in amygdala of learned helpless (LH) compared with nonlearned helpless rats. Prediction analysis showed that the majority of the upregulated miRNAs had target genes enriched for the Wnt signaling pathway. Among altered miRNAs, upregulated miR-128-3p was identified as a top hit based on statistical significance and magnitude of change in LH rats. Target validation showed significant downregulation of Wnt signaling genes in amygdala of LH rats. A discernable increase in expression of amygdalar miR-128-3p along with significant downregulation of key target genes from Wnt signaling (WNT5B, DVL, and LEF1) was noted in MDD subjects. Overexpression of miR-128-3p in a cellular model lead to a marked decrease in the expression of Dvl1 and Lef1 genes, confirming them as validated targets of miR-128-3p. Additional evidence suggested that the amygdala-specific diminished expression of transcriptional repressor Snai1 could be potentially linked to induced miR-128-2 expression in LH rats. Furthermore, an amygdala-specific posttranscriptional switching mechanism could be active between miR-128-3p and RNA binding protein Arpp21 to gain control over their target genes such as Lef1. Conclusion Our study suggests that in amygdala a specific set of miRNAs may play an important role in depression susceptibility, which could potentially be mediated through Wnt signaling.


2021 ◽  
Vol 3 (4) ◽  
pp. 12-24
Author(s):  
Mabao YUAN ◽  
Hanjiao HANG ◽  
Lubin YAN ◽  
Xuanjie HUANG ◽  
Ziyang SANG ◽  
...  

[Objective] Neuroblastoma is the most common pediatric neuroendocrine tumor. Patients with high-risk neuroblastoma have poor clinical outcomes. Understanding the mechanisms underlying neuroblastoma progression could help identify potential therapeutic targets. This study aimed to explore the roles of itchy E3 ubiquitin-protein ligase (ITCH) in neuroblastoma progression using neuroblastoma cell lines and xenograft models of neuroblastoma. [Methods] ITCH-silencing or overexpressing neuroblastoma cells were established using two different human neuroblastoma cell lines, SK-N-AS and SH-SY5Y. In vitro and in vivo experiments were carried out to determine the effects of ITCH on neuroblastoma cell behaviors. The dual-luciferase reporter assay and co-transfection experiments were applied to determine the interaction of ITCH and miR-145-5p during neuroblastoma progression. [Results] In both cell lines, ITCH overexpression significantly promotes the proliferation, migration, and invasion capacities of neuroblastoma cells, while ITCH silencing with ShITCH suppressed neuroblastoma cell proliferation and induced apoptosis. Moreover, overexpression of ITCH decreased 51% and 54% the protein expressions of large tumor suppressor kinase 1 (LATS1), and inhibited 59% and 66% the phosphorylation of Yes-associated protein (YAP), concomitant with 2.02-fold and 2.56-fold increased expressions of cell proliferation marker Ki67 and 2.51-fold and 2.26-fold elevated levels of anti-apoptosis marker Bcl2 in SK-N-AS and SH-SY5Y cells, respectively. The dual-luciferase reporter assay demonstrated that ITCH interacted with miR-145-5p. Further in vitro and xenograft experiments showed that ITCH negatively affected the tumor-suppressive effect of miR-145-5p. [Conclusion] ITCH promotes neuroblastoma cell proliferation and metastasis by inhibiting LATS1 and promoting YAP nuclear translocation.


2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Yan Yang ◽  
Lili Ding ◽  
Qi Zhou ◽  
Li Fen ◽  
Yuhua Cao ◽  
...  

Abstract Background Aurora kinase A (AURKA) has been implicated in the regulation of cell cycle progression, mitosis and a key number of oncogenic signaling pathways in various malignancies including neuroblastoma. Small molecule inhibitors of AURKA have shown potential, but still not as good as expected effects in clinical trials. Little is known about this underlying mechanism. Here, we evaluated the inhibitory effects of AURKA inhibitor MLN8237 on neuroblastoma cells to understand the potential mechanisms responsible for tumor therapy. Methods MLN8237 treatment on neuroblastoma cell line IMR32 was done and in vivo inhibitory effects were investigated using tumor xenograft model. Cellular senescence was evaluated by senescence-associated β-gal Staining assay. Flow cytometry was used to tested cell cycle arrest and cell apoptosis. Senescence-associated signal pathways were detected by western blot. CD133 microbeads and microsphere formation were used to separate and enrich CD133+ cells. AURKA small interfering RNA transfection was carried to downregulate AURKA level. Finally, the combination of MLN8237 treatment with AURKA small interfering RNA transfection were adopted to evaluate the inhibitory effect on neuroblastoma cells. Results We demonstrate that MLN8237, an inhibitor of AURKA, induces the neuroblastoma cell line IMR32 into cellular senescence and G2/M cell phase arrest. Inactivation of AURKA results in MYCN destabilization and inhibits cell growth in vitro and in a mouse model. Although MLN8237 inhibits AURKA kinase activity, it has almost no inhibitory effect on the AURKA protein level. By contrast, MLN8237 treatment leads to abnormal high expression of AURKA in vitro and in vivo. Knockdown of AURKA reduces cell survival. The combination of MLN8237 with AURKA small interfering RNA results in more profound inhibitory effects on neuroblastoma cell growth. Moreover, MLN8237 treatment followed by AURKA siRNA forces senescent cells into apoptosis via suppression of the Akt/Stat3 pathway. Conclusions The effect of AURKA-targeted inhibition of tumor growth plays roles in both the inactivation of AURKA activity and the decrease in the AURKA protein expression level.


2021 ◽  
Vol 13 (607) ◽  
pp. eabd5750
Author(s):  
Balakrishna Koneru ◽  
Ahsan Farooqi ◽  
Thinh H. Nguyen ◽  
Wan Hsi Chen ◽  
Ashly Hindle ◽  
...  

Cancers overcome replicative immortality by activating either telomerase or an alternative lengthening of telomeres (ALT) mechanism. ALT occurs in ~25% of high-risk neuroblastomas, and progression in patients with ALT neuroblastoma during or after front-line therapy is frequent and often fatal. Temozolomide + irinotecan is commonly used as salvage therapy for neuroblastoma. Patient-derived cell lines and xenografts established from patients with relapsed ALT neuroblastoma demonstrated de novo resistance to temozolomide + irinotecan [SN-38 in vitro, P < 0.05; in vivo mouse event-free survival (EFS), P < 0.0001] vs. telomerase-positive neuroblastomas. We observed that ALT neuroblastoma cells manifested constitutive ataxia-telangiectasia mutated (ATM) activation due to spontaneous telomere dysfunction which was not observed in telomerase-positive neuroblastoma cells. We demonstrated that induction of telomere dysfunction resulted in ATM activation that, in turn, conferred resistance to temozolomide + SN-38 (4.2-fold change in IC50, P < 0.001). ATM knockdown (shRNA) or inhibition using a clinical-stage small-molecule inhibitor (AZD0156) reversed resistance to temozolomide + irinotecan in ALT neuroblastoma cell lines in vitro (P < 0.001) and in four ALT xenografts in vivo (EFS, P < 0.0001). AZD0156 showed modest to no enhancement of temozolomide + irinotecan activity in telomerase-positive neuroblastoma cell lines and xenografts. Ataxia telangiectasia and Rad3 related (ATR) inhibition using AZD6738 did not enhance temozolomide + SN-38 activity in ALT neuroblastoma cells. Thus, ALT neuroblastoma chemotherapy resistance occurs via ATM activation and is reversible with ATM inhibitor AZD0156. Combining AZD0156 with temozolomide + irinotecan warrants clinical testing for neuroblastoma.


2019 ◽  
Vol 20 (17) ◽  
pp. 4279 ◽  
Author(s):  
Jung-Mi Oh ◽  
Eunhee Kim ◽  
Sungkun Chun

Autophagy can result in cellular adaptation, as well as cell survival or cell death. Modulation of autophagy is increasingly regarded as a promising cancer therapeutic approach. Ginsenoside compound K (CK), an active metabolite of ginsenosides isolated from Panax ginseng C.A. Meyer, has been identified to inhibit growth of cancer cell lines. However, the molecular mechanisms of CK effects on autophagy and neuroblastoma cell death have not yet been investigated. In the present study, CK inhibited neuroblastoma cell proliferation in vitro and in vivo. Treatment by CK also induced the accumulation of sub-G1 population, and caspase-dependent apoptosis in neuroblastoma cells. In addition, CK promotes autophagosome accumulation by inducing early-stage autophagy but inhibits autophagic flux by blocking of autophagosome and lysosome fusion, the step of late-stage autophagy. This effect of CK appears to be mediated through the induction of intracellular reactive oxygen species (ROS) and mitochondria membrane potential loss. Moreover, chloroquine, an autophagy flux inhibitor, further promoted CK-induced apoptosis, mitochondrial ROS induction, and mitochondria damage. Interestingly, those promoted phenomena were rescued by co-treatment with a ROS scavenging agent and an autophagy inducer. Taken together, our findings suggest that ginsenoside CK induced ROS-mediated apoptosis and autophagic flux inhibition, and the combination of CK with chloroquine, a pharmacological inhibitor of autophagy, may be a novel therapeutic potential for the treatment of neuroblastoma.


Author(s):  
Ning Jiang ◽  
Yihao Liao ◽  
Miaomiao Wang ◽  
Youzhi Wang ◽  
Keke Wang ◽  
...  

Abstract Background The incidence of bladder urothelial carcinoma (UC), a common malignancy of the urinary tract, is approximately three times higher in men than in women. High expression of the mitotic kinase BUB1 is associated with the occurrence and development of several cancers, although the relationship between BUB1 and bladder tumorigenesis remains unclear. Methods Using a microarray approach, we found increased BUB1 expression in human BCa. The association between BUB1 and STAT3 phosphorylation was determined through molecular and cell biological methods. We evaluated the impact of pharmacologic inhibition of BUB1 kinase activity on proliferation and BCa progression in vitro and in vivo. Results In this study, we found that BUB1 expression was increased in human bladder cancer (BCa). We further identified through a series of molecular and cell biological approaches that BUB1 interacted directly with STAT3 and mediated the phosphorylation of STAT3 at Ser727. In addition, the findings that pharmacologic inhibition of BUB1 kinase activity significantly suppressed BCa cell proliferation and the progression of bladder cancer in vitro and in vivo were further verified. Finally, we found that the BUB1/STAT3 complex promoted the transcription of STAT3 target genes and that depletion of BUB1 and mutation of the BUB1 kinase domain abrogated this transcriptional activity, further highlighting the critical role of kinase activity in the activation of STAT3 target genes. A pharmacological inhibitor of BUB1 (2OH-BNPP1) was able to significantly inhibit the growth of BCa cell xenografts. Conclusion This study showed that the BUB1 kinase drives the progression and proliferation of BCa by regulating the transcriptional activation of STAT3 signaling and may be an attractive candidate for therapeutic targeting in BCa.


2021 ◽  
Author(s):  
Tim van Groningen ◽  
Camilla U. Niklasson ◽  
Alvin Chan ◽  
Nurdan Akogul ◽  
Ellen M. Westerhout ◽  
...  

Neuroblastoma is a pediatric tumor of the adrenergic sympathetic lineage. Most high risk neuroblastoma go in complete clinical remission by chemotherapy, which is subsequently complemented by retinoic acid (RA) maintenance therapy. However, by unresolved mechanisms most tumors ultimately relapse as therapy-resistant disease. Neuroblastoma cell lines were recently found to include, besides lineage committed adrenergic (ADRN) tumor cells, also immature mesenchymal (MES) tumor cells. Here, we report that MES-type cells synthesize RA and require this metabolite for proliferation and motility. MES cells are even resistant to RA in vitro. MES cells appear to resemble Schwann Cell Precursors (SCP), which are motile precursors of the adrenergic lineage. MES and SCP cells express shared RA-synthesis and RA-target genes. Endogenous RA synthesis and RA resistance thus stem from normal programs of lineage precursors that are maintained in an immature tumor cell fraction. These cells are fully malignant in orthotopic patient-derived xenograft models and may mediate development of drug-resistant relapses.


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