SUMOylation of PUM2 promotes the vasculogenic mimicry of glioma cells via regulating CEBPD

CEBPD aggravates apoptosis and oxidative stress of neuron after ischemic stroke by Nrf2/HO-1 pathway

CCAAT enhancer binding protein delta (CEBPD) is a transcription factor and plays an important role in apoptosis and oxidative stress, which are the main pathogenesis of ischemic stroke. However, whether CEBPD regulates ischemic stroke through targeting apoptosis and oxidative stress is unclear. Therefore, to answer this question, rat middle cerebral artery occlusion (MCAO) reperfusion model and oxygen-glucose deprivation/reoxygenation (OGD/R) primary cortical neuron were established to mimic ischemic reperfusion injury. We found that CEBPD was upregulated and accompanied with increased neurological deficit scores and infarct size, and decreased neuron in MCAO rats. The siRNA targeted CEBPD inhibited CEBPD expression in rats, and meanwhile lentivirus system was used to blocked CEBPD expression in primary neuron. CEBPD degeneration decreased neurological deficit scores, infarct size and brain water content of MCAO rats. Knockdown of CEBPD enhanced cell viability and reduced apoptosis as well as oxidative stress in vivo and in vitro. CEBPD silencing promoted the translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) to the nucleus and the expression of heme oxygenase 1 (HO-1). Newly, CEBPD facilitated the transcription of cullin 3 (CUL3), which intensified ischemic stroke through Nrf2/HO-1 pathway that was proposed by our team in the past. In conclusion, targeting CEBPD-CUL3-Nrf2/HO-1 axis may be contributed to cerebral ischemia therapy.

The deubiquitinase USP7 and E3 ligase TRIM21 regulate vasculogenic mimicry and malignant progression of RMS by balancing SNAI2 homeostasis

BACKGROUND

Rhabdomyosarcoma (RMS) is a rare malignancy and the most common soft tissue sarcoma in children. Vasculogenic mimicry (VM) is a novel tumor microcirculation model different from traditional tumor angiogenesis, which does not rely on endothelial cells to provide sufficient blood supply for tumor growth. In recent years, VM has been confirmed to be closely associated with tumor progression. However, the ability of RMS to form VM has not yet been reported.

METHODS

Immunohistochemistry, RT-qPCR and western blot were used to test the expression level of SNAI2 and its clinical significance. The biological function in regulating vasculogenic mimicry and malignant progression of SNAI2 was examined both in vitro and in vivo. Mass spectrometry, co-immunohistochemistry, immunofluorescence staining, and ubiquitin assays were performed to explore the regulatory mechanism of SNAI2.

RESULTS

Our study indicated that SNAI2 was abnormally expressed in patients with RMS and RMS cell lines and promoted the proliferation and metastasis of RMS. Through cell tubule formation experiments, nude mice Matrigel plug experiments, and immunohistochemistry (IHC), we confirmed that RMS can form VM and that SNAI2 promotes the formation of VM. Due to SNAI2 is a transcription factor that is not easily drugged, we used Co-IP combined with mass spectrometry to screen for the SNAI2-binding protein USP7 and TRIM21. USP7 depletion inhibited RMS VM formation, proliferation and metastasis by promoting SNAI2 degradation. We further demonstrated that TRIM21 is expressed at low levels in human RMS tissues and inhibits VM in RMS cells. TRIM21 promotes SNAI2 protein degradation through ubiquitination in the RMS. The deubiquitinase USP7 and E3 ligase TRIM21 function in an antagonistic rather than competitive mode and play a key role in controlling the stability of SNAI2 to determine the VM formation and progression of RMS.

CONCLUSION

Our findings reveal a previously unknown mechanism by which USP7 and TRIM21 balance the level of SNAI2 ubiquitination, determining RMS vasculogenic mimicry, proliferation, and migration. This new mechanism may provide new targeted therapies to inhibit the development of RMS by restoring TRIM21 expression or inhibiting USP7 expression in RMS patients with high SNAI2 protein levels.

GPR65 sensing tumor-derived lactate induces HMGB1 release from TAM via the cAMP/PKA/CREB pathway to promote glioma progression

BACKGROUND

Lactate has emerged as a critical regulator within the tumor microenvironment, including glioma. However, the precise mechanisms underlying how lactate influences the communication between tumor cells and tumor-associated macrophages (TAMs), the most abundant immune cells in glioma, remain poorly understood. This study aims to elucidate the impact of tumor-derived lactate on TAMs and investigate the regulatory pathways governing TAM-mediated tumor-promotion in glioma.

METHODS

Bioinformatic analysis was conducted using datasets from TCGA and CGGA. Single-cell RNA-seq datasets were analyzed by using UCSC Cell Browser and Single Cell Portal. Cell proliferation and mobility were evaluated through CCK8, colony formation, wound healing, and transwell assays. Western blot and immunofluorescence staining were applied to assess protein expression and cell distribution. RT-PCR and ELISA were employed to identify the potential secretory factors. Mechanistic pathways were explored by western blotting, ELISA, shRNA knockdown, and specific inhibitors and activators. The effects of pathway blockades were further assessed using subcutaneous and intracranial xenograft tumor models in vivo.

RESULTS

Elevated expressions of LDHA and MCT1 were observed in glioma and exhibited a positive correlation with M2-type TAM infiltration. Lactate derived from glioma cells induced TAMs towards M2-subtype polarization, subsequently promoting glioma cells proliferation, migration, invasion, and mesenchymal transition. GPR65, highly expressed on TAMs, sensed lactate-stimulation in the TME, fueling glioma cells malignant progression through the secretion of HMGB1. GPR65 on TAMs triggered HMGB1 release in response to lactate stimulation via the cAMP/PKA/CREB signaling pathway. Disrupting this feedback loop by GPR65-knockdown or HMGB1 inhibition mitigated glioma progression in vivo.

CONCLUSION

These findings unveil the intricate interplay between TAMs and tumor cells mediated by lactate and HMGB1, driving tumor progression in glioma. GPR65, selectively highly expressed on TAMs in glioma, sensed lactate stimulation and fostered HMGB1 secretion via the cAMP/PKA/CREB signaling pathway. Blocking this feedback loop presents a promising therapeutic strategy for GBM.

Norad Competently Binds with Pum2 to Regulate Neuronal Apoptosis and Play a Neuroprotective Role After SAH in Mice

Subarachnoid Hemorrhage (SAH) is a cerebrovascular disorder that has been found to have severe consequences, including a high mortality and disability rate. Research has indicated that neuronal death, particularly apoptosis, plays a major role in the neurological impairment that follows SAH. RNA-binding protein Pum2 can interfere with translation or other biological functions by connecting to the UGUAHAUA sequence on RNA. Noncoding RNA activated by DNA damage (Norad) contains some Pum2 recognition sequences, which may bind to Pum2 protein and affect its capacity to attach to target mRNA. The time course expression of Norad and Pum2 after SAH is analyzed by establishing a mouse SAH model. Subsequently, the purpose of this study is to investigate the potential role and mechanism of the Norad-Pum2 axis after SAH using lentivirus overexpression of Pum2 and knockdown of Norad. Analysis of Pum2 and Norad levels reveal that the former is significantly reduce and the latter is significantly increased in the SAH group compared to the sham group. Subsequent overexpression of Pum2 and Norad knockdown is found to reduce SAH-induced oxidative stress, neuronal apoptosis, and ultimately improve behavioral and cognitive changes in SAH mice. Our study indicates that Norad-Pum2 acts as a neuromodulator in SAH, and that by increasing Pum2 and decreasing Norad levels, SAH-induced neuronal apoptosis can be reduced and neurological deficits alleviated. Consequently, Norad-Pum2 may be a promising therapeutic target for SAH.

SNORD17-mediated KAT6B mRNA 2'-O-methylation regulates vasculogenic mimicry in glioblastoma cells

Glioblastoma (GBM) is a primary tumor in the intracranial compartment. Vasculogenic mimicry (VM) is a process in which a pipeline of tumor cells that provide blood support to carcinogenic cells is formed, and studying VM could provide a new strategy for clinical targeted treatment of GBM. In the present study, we found that SNORD17 and ZNF384 were significantly upregulated and promoted VM in GBM, whereas KAT6B was downregulated and inhibited VM in GBM. RTL-P assays were performed to verify the 2'-O-methylation of KAT6B by SNORD17; IP assays were used to detect the acetylation of ZNF384 by KAT6B. In addition, the binding of ZNF384 to the promoter regions of VEGFR2 and VE-cadherin promoted transcription, as validated by chromatin immunoprecipitation and luciferase reporter assays. And finally, knockdown of SNORD17 and ZNF384 combined with KAT6B overexpression effectively reduced the xenograft tumor size, prolonged the survival time of nude mice and reduced the number of VM channels. This study reveals a novel mechanism of the SNORD17/KAT6B/ZNF384 axis in modulating VM development in GBM that may provide a new goal for the comprehensive treatment of GBM.

Emerging trends in post-translational modification: Shedding light on Glioblastoma multiforme

Recent multi-omics studies, including proteomics, transcriptomics, genomics, and metabolomics have revealed the critical role of post-translational modifications (PTMs) in the progression and pathogenesis of Glioblastoma multiforme (GBM). Further, PTMs alter the oncogenic signaling events and offer a novel avenue in GBM therapeutics research through PTM enzymes as potential biomarkers for drug targeting. In addition, PTMs are critical regulators of chromatin architecture, gene expression, and tumor microenvironment (TME), that play a crucial function in tumorigenesis. Moreover, the implementation of artificial intelligence and machine learning algorithms enhances GBM therapeutics research through the identification of novel PTM enzymes and residues. Herein, we briefly explain the mechanism of protein modifications in GBM etiology, and in altering the biologics of GBM cells through chromatin remodeling, modulation of the TME, and signaling pathways. In addition, we highlighted the importance of PTM enzymes as therapeutic biomarkers and the role of artificial intelligence and machine learning in protein PTM prediction.

The driving mechanism and targeting value of mimicry between vascular endothelial cells and tumor cells in tumor progression

The difficulty and poor prognosis of malignant tumor have always been a difficult problem to be solved. The internal components of solid tumor are complex, including tumor cells, stromal cells and immune cells, which play an important role in tumor proliferation, migration, metastasis and drug resistance. Hence, targeting of only the tumor cells will not likely improve survival. Various studies have reported that tumor cells and endothelial cells have high plasticity, which is reflected in the fact that they can simulate each other's characteristics by endothelial-mesenchymal transition (EndMT) and vasculogenic mimicry (VM). In this paper, this mutual mimicry concept was integrated and reviewed for the first time, and their similarities and implications for tumor development are discussed. At the same time, possible therapeutic methods are proposed to provide new directions and ideas for clinical targeted therapy and immunotherapy of tumor.

A novel peptide P1-121aa encoded by STK24P1 regulates vasculogenic mimicry via ELF2 phosphorylation in glioblastoma

Glioblastoma (GBM) is the most common malignant tumor of the central nervous system. Vasculogenic mimicry (VM) is a hematological system composed of tumor cells that exert blood perfusion without relying on vascular endothelial cells. The current poor results of anti-vascular therapy for clinical GBM are associated with the presence of VM; therefore, it is important to investigate VM formation in GBM. Our results demonstrate that STK24P1 encodes P1-121aa with a kinase structural domain, and in vitro kinase assays demonstrated that P1-121aa mediates modification of ELF2 phosphorylation. ChIP and dual luciferase reporter gene assays demonstrated that the transcription factor ELF2 binds to VE-cadherin and the VEGFR2 promoter region, thereby promoting VM formation in glioma cells. P1-121aa, encoded by the pseudogene STK24P1, phosphorylates ELF2 at S107, increasing the stability of the ELF2 protein. ELF2 promotes VEGFR2 and VE-cadherin expression at the transcriptional level, which in turn promotes VM in GBM. This study demonstrates the important roles of STK24P1, P1-121aa, and ELF2 in regulating VM in GBM, which could provide potential targets for GBM treatment.

Cell-permeable peptide-based delivery vehicles useful for subcellular targeting and beyond

Personal medicine aims to provide tailor-made diagnostics and treatments and has been emerged as a promising but challenging strategy during the last years. This includes the active delivery and localization of a therapeutic compound to a targeted site of action within a cell. An example being targeting the interference of a distinct protein-protein interaction (PPI) within the cell nucleus, mitochondria or other subcellular location. Therefore, not only the cell membrane has to be overcome but also the final intracellular destination has to be reached. One approach which fulfills both requirements is to use short peptide sequences that are able to translocate into cells as targeting and delivery vehicles. In fact, recent progress in this field demonstrates how these tools can modulate the pharmacological parameters of a drug without compromising its biological activity. Beside classical targets that are addressed by various small molecule drugs such as receptors, enzymes, or ion channels, PPIs have received increasing attention as potential therapeutic targets. Within this review, we will provide a recent update on cell-permeable peptides targeting subcellular destinations. We include chimeric peptide probes that combine cell-penetrating peptides (CPPs) and a targeting sequence, as well peptides having intrinsic cell-permeability and which are often used to target PPIs.

Knockdown of UBE2I inhibits tumorigenesis and enhances chemosensitivity of cholangiocarcinoma via modulating p27kip1 nuclear export

The asymptomatic nature of cholangiocarcinoma (CCA), particularly during its early stages, in combination with its high aggressiveness and chemoresistance, significantly compromises the efficacy of current therapeutic options, contributing to a dismal prognosis. As a tumor suppressor that inhibits the cell cycle, abnormal cytoplasmic p27kip1 localization is related to chemotherapy resistance and often occurs in various cancers, including CCA. Nevertheless, the underlying mechanism is unclear. SUMOylation, which is involved in regulating subcellular localization and the cell cycle, is a posttranslational modification that regulates p27kip1 activity. Here, we confirmed that UBE2I, as the only key enzyme for SUMOylation, was highly expressed and p27kip1 was downregulated in CCA tissues, which were associated with poor outcomes in CCA. Moreover, UBE2I silencing inhibited CCA cell proliferation, delayed xenograft tumor growth in vivo, and sensitized CCA cells to the chemotherapeutics, which may be due to cell cycle arrest induced by p27kip1 nuclear accumulation. According to the immunoprecipitation result, we found that UBE2I could bind p27kip1, and the binding amount of p27kip1 and SUMO-1 decreased after UBE2I silencing. Moreover, nuclear retention of p27kip1 was induced by UBE2I knockdown and SUMOylation or CRM1 inhibition, further suggesting that UBE2I could cooperate with CRM1 in the nuclear export of p27kip1. These data indicate that UBE2I-mediated SUMOylation is a novel regulatory mechanism that underlies p27kip1 export and controls CCA tumorigenesis, providing a therapeutic option for CCA treatment.

Targeting Transcription Factors ATF5, CEBPB and CEBPD with Cell-Penetrating Peptides to Treat Brain and Other Cancers

Developing novel therapeutics often follows three steps: target identification, design of strategies to suppress target activity and drug development to implement the strategies. In this review, we recount the evidence identifying the basic leucine zipper transcription factors ATF5, CEBPB, and CEBPD as targets for brain and other malignancies. We describe strategies that exploit the structures of the three factors to create inhibitory dominant-negative (DN) mutant forms that selectively suppress growth and survival of cancer cells. We then discuss and compare four peptides (CP-DN-ATF5, Dpep, Bpep and ST101) in which DN sequences are joined with cell-penetrating domains to create drugs that pass through tissue barriers and into cells. The peptide drugs show both efficacy and safety in suppressing growth and in the survival of brain and other cancers in vivo, and ST101 is currently in clinical trials for solid tumors, including GBM. We further consider known mechanisms by which the peptides act and how these have been exploited in rationally designed combination therapies. We additionally discuss lacunae in our knowledge about the peptides that merit further research. Finally, we suggest both short- and long-term directions for creating new generations of drugs targeting ATF5, CEBPB, CEBPD, and other transcription factors for treating brain and other malignancies.

The mechanism of BUD13 m6A methylation mediated MBNL1-phosphorylation by CDK12 regulating the vasculogenic mimicry in glioblastoma cells

Vasculogenic mimicry (VM) is an endothelium-independent tumor microcirculation that provides adequate blood supply for tumor growth. The presence of VM greatly hinders the treatment of glioblastoma (GBM) with anti-angiogenic drugs. Therefore, targeting VM formation may be a feasible therapeutic strategy for GBM. The research aimed to evaluate the roles of BUD13, CDK12, MBNL1 in regulating VM formation of GBM. BUD13 and CDK12 were upregulated and MBNL1 was downregulated in GBM tissues and cells. Knockdown of BUD13, CDK12, or overexpression of MBNL1 inhibited GBM VM formation. METTL3 enhanced the stability of BUD13 mRNA and upregulated its expression through m6A methylation. BUD13 enhanced the stability of CDK12 mRNA and upregulated its expression. CDK12 phosphorylated MBNL1, thereby regulating VM formation of GBM. The simultaneous knockdown of BUD13, CDK12, and overexpression of MBNL1 reduced the volume of subcutaneously transplanted tumors in nude mice and prolonged the survival period. Thus, the BUD13/CDK12/MBNL1 axis plays a crucial role in regulating VM formation of GBM and provides a potential target for GBM therapy.

Prognostic Value and Biological Function of Galectins in Malignant Glioma

Malignant glioma is the most common solid tumor of the adult brain, with high lethality and poor prognosis. Hence, identifying novel and reliable biomarkers can be advantageous for diagnosing and treating glioma. Several galectins encoded by LGALS genes have recently been reported to participate in the development and progression of various tumors; however, their detailed role in glioma progression remains unclear. Herein, we analyzed the expression and survival curves of all LGALS across 2,217 patients with glioma using The Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA), and Rembrandt databases. By performing multivariate Cox analysis, we built a survival model containing LGALS1, LGALS3, LGALS3BP, LGALS8, and LGALS9 using TCGA database. The prognostic power of this panel was assessed using CGGA and Rembrandt datasets. ESTIMATE and CIBERSORT algorithms confirmed that patients in high-risk groups exhibited significant stromal and immune cell infiltration, immunosuppression, mesenchymal subtype, and isocitrate dehydrogenase 1 (IDH1) wild type. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), CancerSEA, and Gene Set Enrichment Analysis (GSEA) showed that pathways related to hypoxia, epithelial-to-mesenchymal transition (EMT), stemness, and inflammation were enriched in the high-risk group. To further elucidate the function of LGALS in glioma, we performed immunohistochemical staining of tissue microarrays (TMAs), Western blotting, and cell viability, sphere formation, and limiting dilution assays following lentiviral short hairpin RNA (shRNA)-mediated LGALS knockdown. We observed that LGALS expression was upregulated in gliomas at both protein and mRNA levels. LGALS could promote the stemness maintenance of glioma stem cells (GSCs) and positively correlate with M2-tumor-associated macrophages (TAMs) infiltration. In conclusion, we established a reliable survival model for patients with glioma based on LGALS expression and revealed the essential roles of LGALS genes in tumor growth, immunosuppression, stemness maintenance, pro-neural to mesenchymal transition, and hypoxia in glioma.

MicroRNA-665-3p exacerbates nonalcoholic fatty liver disease in mice

Oxidative stress and chronic inflammation are major culprits of nonalcoholic fatty liver disease (NAFLD). MicroRNA-665-3p (miR-665-3p) is implicated in regulating inflammation and oxidative stress; however, its role and molecular basis in NAFLD remain elusive. Herein, we measured a significant upregulation of miR-665-3p level in the liver and primary hepatocytes upon high fat diet (HFD) or 0.5 mmol/L palmitic acid plus 1.0 mmol/L oleic acid stimulation, and the elevated miR-665-3p expression aggravated oxidative stress, inflammation and NAFLD progression in mice. In contrast, miR-665-3p inhibition by the miR-665-3p antagomir significantly prevented HFD-induced oxidative stress, inflammation and hepatic dysfunction in vivo. Manipulation of miR-665-3p in primary hepatocytes also caused similar phenotypic alterations in vitro. Mechanistically, we demonstrated that miR-665-3p directly bound to the 3'-untranslated region of fibronectin type III domain-containing 5 (FNDC5) to downregulate its expression and inactivated the downstream AMP-activated protein kinase alpha (AMPKα) pathway, thereby facilitating oxidative stress, inflammation and NAFLD progression. Our findings identify miR-665-3p as an endogenous positive regulator of NAFLD via inactivating FNDC5/AMPKα pathway, and inhibiting miR-665-3p may provide novel therapeutic strategies to treat NAFLD.

LOXL1-AS1 communicating with TIAR modulates vasculogenic mimicry in glioma via regulation of the miR-374b-5p/MMP14 axis

At present, growing evidence indicates that long non‐coding RNAs (lncRNAs) participate in the progression of glioma. The function of LOXL1‐AS1 in vasculogenic mimicry (VM) in glioma remains unclear. First, the expressions of TIAR, the lncRNA LOXL1‐AS1, miR‐374b‐5p and MMP14 were examined by qRT‐PCR and Western blot in both, glioma tissues and glioma cell lines. Proliferation, migration, invasion and tube formation assays were conducted to evaluate the roles of TIAR, LOXL1‐AS1, miR‐374b‐5p and MMP14 in malignant cellular behaviours in glioma cells. A nude mouse xenograft model and dual staining for CD34 and PAS were used to assess whether VM was affected by TIAR, LOXL1‐AS1 or miR‐374b‐5p in vivo. In this study, low levels of TIAR and high levels of LOXL1‐AS1 were found in glioma cells and tissues. TIAR downregulated the expression of LOXL1‐AS1 by destabilizing it. LOXL1‐AS1 acted like a miRNA sponge towards miR‐374b‐5p so that downregulation of the former greatly inhibited cell proliferation, migration, invasion and VM. Additionally, miR‐374b‐5p overexpression repressed malignant biological behaviours and VM in glioma by modifying MMP14. In summary, we demonstrated that TIAR combined with LOXL1‐AS1 modulates VM in glioma via the miR‐374b‐5p/MMP14 axis, revealing novel targets for glioma therapy.

Cervical Cancer Development: Implications of HPV16 E6E7-NFX1-123 Regulated Genes

Simple Summary

High-risk human papillomavirus (HPV) causes 4.5% of cancers and nearly all cervical cancers. HPV’s carcinogenic potential depends on its misappropriation of cellular proteins by HPV’s oncoproteins E6 and E7. High-risk HPV type 16 (HPV16) E6 binds directly to the cellular protein NFX1-123 and dysregulates proliferation, differentiation, and immunity genes. The effect of HPV16 E7 has not been studied in relation to HPV16 E6-NFX1-123-mediated dysregulation. As HPV expresses both oncogenes, and HPV carcinogenesis requires E6 and E7, it is valuable to investigate what dysregulations occur in this context. It is also important to understand their clinical and prognostic ramifications. This study’s goal was to define the gene expression profile regulated by HPV16 E6, E7, and NFX1-123 across cervical precancers and cancers, identify genes correlating with disease progression, assess patient survival, and validate findings in cell models. Finding correlates of survival and disease progression aids in biomarker identification and focuses future studies.

Abstract

High-risk human papillomavirus (HR HPV) causes nearly all cervical cancers, half of which are due to HPV type 16 (HPV16). HPV16 oncoprotein E6 (16E6) binds to NFX1-123, and dysregulates gene expression, but their clinical implications are unknown. Additionally, HPV16 E7’s role has not been studied in concert with NFX1-123 and 16E6. HR HPVs express both oncogenes, and transformation requires their expression, so we sought to investigate the effect of E7 on gene expression. This study’s goal was to define gene expression profiles across cervical precancer and cancer stages, identify genes correlating with disease progression, assess patient survival, and validate findings in cell models. We analyzed NCBI GEO datasets containing transcriptomic data linked with cervical cancer stage and utilized LASSO analysis to identify cancer-driving genes. Keratinocytes expressing 16E6 and 16E7 (16E6E7) and exogenous NFX1-123 were tested for LASSO-identified gene expression. Ten out of nineteen genes correlated with disease progression, including CEBPD, NOTCH1, and KRT16, and affected survival. 16E6E7 in keratinocytes increased CEBPD, KRT16, and SLPI, and decreased NOTCH1. Exogenous NFX1-123 in 16E6E7 keratinocytes resulted in significantly increased CEBPD and NOTCH1, and reduced SLPI. This work demonstrates the clinical relevance of CEBPD, NOTCH1, KRT16, and SLPI, and shows the regulatory effects of 16E6E7 and NFX1-123.

Cell-Penetrating CEBPB and CEBPD Leucine Zipper Decoys as Broadly Acting Anti-Cancer Agents

Simple Summary

The gene-regulatory factors ATF5, CEBPB and CEBPD promote survival, growth, metastasis and treatment resistance of a range of cancer cell types. Presently, no drugs target all three at once. Here, with the aim of treating cancers, we designed novel cell-penetrating peptides that interact with and inactivate all three. The peptides Bpep and Dpep kill a range of cancer cell types in culture and in animals. In animals with tumors, they also significantly increase survival time. In contrast, they do not affect survival of non-cancer cells and have no apparent side effects in animals. The peptides work in combination with other anti-cancer treatments. Mechanism studies of how the peptides kill cancer cells indicate a decrease in survival proteins and increase in death proteins. These studies support the potential of Bpep and Dpep as novel, safe agents for the treatment of a variety of cancer types, both as mono- and combination therapies.

Abstract

Transcription factors are key players underlying cancer formation, growth, survival, metastasis and treatment resistance, yet few drugs exist to directly target them. Here, we characterized the in vitro and in vivo anti-cancer efficacy of novel synthetic cell-penetrating peptides (Bpep and Dpep) designed to interfere with the formation of active leucine-zipper-based dimers by CEBPB and CEBPD, transcription factors implicated in multiple malignancies. Both peptides similarly promoted apoptosis of multiple tumor lines of varying origins, without such effects on non-transformed cells. Combined with other treatments (radiation, Taxol, chloroquine, doxorubicin), the peptides acted additively to synergistically and were fully active on Taxol-resistant cells. The peptides suppressed expression of known direct CEBPB/CEBPD targets IL6, IL8 and asparagine synthetase (ASNS), supporting their inhibition of transcriptional activation. Mechanisms by which the peptides trigger apoptosis included depletion of pro-survival survivin and a required elevation of pro-apoptotic BMF. Bpep and Dpep significantly slowed tumor growth in mouse models without evident side effects. Dpep significantly prolonged survival in xenograft models. These findings indicate the efficacy and potential of Bpep and Dpep as novel agents to treat a variety of cancers as mono- or combination therapies.

SUMOylation Regulator-Related Molecules Can Be Used as Prognostic Biomarkers for Glioblastoma

Introduction

SUMOylation is one of the post-translational modifications. The relationship between the expression of SUMOylation regulators and the prognosis of glioblastoma is not quite clear.

Materials and Methods

The single nucleotide variant data, the transcriptome data, and survival information were acquired from The Cancer Genome Atlas, Gene Expression Omnibus, and cBioportal database. Wilcoxon test was used to analyze differentially expressed genes between glioblastoma and normal brain tissues. Gene set enrichment analysis was conducted to find the possible functions. One risk scoring model was built by the least absolute shrinkage and selection operator Cox regression. Kaplain–Meier survival curves and receiver operating characteristic curves were applied to evaluate the effectiveness of the model in predicting the prognosis of glioblastoma.

Results

Single-nucleotide variant mutations were found in SENP7, SENP3, SENP5, PIAS3, RANBP2, USPL1, SENP1, PIAS2, SENP2, and PIAS1. Moreover, UBE2I, UBA2, PIAS3, and SENP1 were highly expressed in glioblastoma, whereas PIAS1, RANBP2, SENP5, and SENP2 were downregulated in glioblastoma. Functional enrichment analysis showed that the SUMOylation regulators of glioblastoma might involve cell cycle, DNA replication, and other functions. A prognostic model of glioblastoma was constructed based on SUMOylation regulator-related molecules (ATF7IP, CCNB1IP1, and LBH). Kaplain–Meier survival curves and receiver operating characteristic curves showed that the model had a strong ability to predict the overall survival of glioblastoma.

Conclusion

This study analyzed the expression of 15 SUMOylation regulators in glioblastoma. The risk assessment model was constructed based on the SUMOylation regulator-related genes, which had a strong predictive ability for the overall survival of patients with glioblastoma. It might provide targets for the study of the relationship between SUMOylation and glioblastoma.