Myc-associated Zinc Finger Protein Research Articles

MAZ promotes thyroid cancer progression by driving transcriptional reprogram and enhancing ERK1/2 activation

Papillary thyroid carcinoma (PTC) is the most common type of thyroid malignancies worldwide. Oncogenic transcription factors (TFs) drive transcriptional reprogramming and tumorigenesis. The myc-associated zinc finger protein (MAZ) is one of the Myc family TFs. The role of MAZ in PTC pathogenesis is still largely unknown. Here, we report that MAZ profoundly promotes proliferation of PTC cells ex vivo and in vivo through activating MAPK signaling. We firstly profiled gene expression of PTC cells after silencing of MAZ. BRAF, KRAS and LOC547 were identified as important target genes of TF MAZ. In particular, TF MAZ bound to the promoters of BRAF or KRAS and significantly increased their transcription and expression levels. Meanwhile, MAZ could noticeably elevate LOC547 transcription and expression as a TF. High levels of LOC547 relocated ACTN4 protein from the nucleus to the cytosol, improved protein-protein interactions between ACTN4 and EGFR in the cytosol, enhanced ERK1/2 phosphorylation, activated the MAPK signaling and, thus, promoted PTC progression. Our data identify a previously underappreciated MAZ-controlled transcriptional reprogram and ERK1/2 activation via BRAF, KRAS and LOC547. Our data illustrate that activation of the MAZ-controlled axis promotes thyroid tumorigenesis. These insights would advance our knowledge of the role of TFs in cancer development and highlight the potential of TFs as future targets for treatments against cancers.

MAZ-mediated up-regulation of BCKDK reprograms glucose metabolism and promotes growth by regulating glucose-6-phosphate dehydrogenase stability in triple-negative breast cancer

Tumour metabolic reprogramming is pivotal for tumour survival and proliferation. Investigating potential molecular mechanisms within the heterogeneous and clinically aggressive triple-negative breast cancer (TNBC) subtype is essential to identifying novel therapeutic targets. Accordingly, we investigated the role of branched-chain α-keto acid dehydrogenase kinase (BCKDK) in promoting tumorigenesis in TNBC. We analysed The Cancer Genome Atlas dataset and immunohistochemically stained surgical specimens to investigate BCKDK expression and its prognostic implications in TNBC. The effects of BCKDK on tumorigenesis were assessed using cell viability, colony formation, apoptosis, and cell cycle assays, and subsequently validated in vivo. Metabolomic screening was performed via isotope tracer studies. The downstream target was confirmed using mass spectrometry and a co-immunoprecipitation experiment coupled with immunofluorescence analysis. Upstream transcription factors were also examined using chromatin immunoprecipitation and luciferase assays. BCKDK was upregulated in TNBC tumour tissues and associated with poor prognosis. BCKDK depletion led to reduced cell proliferation both in vitro and vivo. MYC-associated zinc finger protein (MAZ) was confirmed as the major transcription factor directly regulating BCKDK expression in TNBC. Mechanistically, BCKDK interacted with glucose-6-phosphate dehydrogenase (G6PD), leading to increased flux in the pentose phosphate pathway for macromolecule synthesis and detoxification of reactive oxygen species. Forced expression of G6PD rescued the growth defect in BCKDK-deficient cells. Notably, the small-molecule inhibitor of BCKDK, 3,6-dichlorobenzo(b)thiophene-2-carboxylic acid, exhibited anti-tumour effects in a patient-derived tumour xenograft model. Our findings hold significant promise for developing targeted therapies aimed at disrupting the MAZ/BCKDK/G6PD signalling pathway, offering potential advancements in treating TNBC through metabolic reprogramming.

The Myc-associated zinc finger protein epigenetically controls expression of interferon-γ-stimulated genes by recruiting STAT1 to chromatin

The MYC-Associated Zinc Finger Protein (MAZ) plays important roles in chromatin organization and gene transcription regulation. Dysregulated expression of MAZ causes diseases, such as glioblastoma, breast cancer, prostate cancer, and liposarcoma. Previously, it has been reported that MAZ controls the proinflammatory response in colitis and colon cancer via STAT3 signaling, suggesting that MAZ is involved in regulating immunity-related pathways. However, the molecular mechanism underlying this regulation remains elusive. Here, we investigate the regulatory effect of MAZ on interferon-gamma (IFN-γ)-stimulated genes via STAT1, a protein that plays an essential role in immune responses to viral, fungal, and mycobacterial pathogens. We demonstrate that about 80% of occupied STAT1-binding sites colocalize with occupied MAZ-binding sites in HAP1/K562 cells after IFN-γ stimulation. MAZ depletion significantly reduces STAT1 binding in the genome. By analyzing genome-wide gene expression profiles in the RNA-Seq data, we show that MAZ depletion significantly suppresses a subset of the immune response genes, which include the IFN-stimulated genes IRF8 and Absent in Melanoma 2. Furthermore, we find that MAZ controls expression of the immunity-related genes by changing the epigenetic landscape in chromatin. Our study reveals an important role for MAZ in regulating immune-related gene expression.

NSUN2 promotes lung adenocarcinoma progression through stabilizing PIK3R2 mRNA in an m5C-dependent manner.

It is well known that 5-methylcytosine (m5C) is involved in variety of crucial biological processes in cancers. However, its biological roles in lung adenocarcinoma (LAUD) remain to be determined. The LUAD samples were used to assess the clinical value of NOP2/Sun RNA Methyltransferase 2 (NSUN2). Dot blot was used to determine global m5C levels. ChIP and dual-luciferase assays were performed to investigate the MYC-associated zinc finger protein (MAZ)-binding sites in NSUN2 promoter. RNA-seq was used to explore the downstream molecular mechanisms of NSUN2. Dual luciferase reporter assay, m5C-RIP-qPCR, and mRNA stability assay were conducted to explore the effect of NSUN2-depletion on target genes. Cell viability, transwell, and xenograft mouse model were designed to demonstrate the characteristic of NSUN2 in promoting LUAD progression. The m5C methyltransferase NSUN2 was highly expressed and caused elevated m5C methylation in LUAD samples. Mechanistically,MAZ positively regulated the transcription of NSUN2 and was related to poor survival of LUAD patients. Silencing NSUN2 decreased the global m5C levels, suppressed proliferation, migration and invasion, and inhibited activation of PI3K-AKT signaling in A549 and SPAC-1 cells. Phosphoinositide-3-Kinase Regulatory Subunit 2 (PIK3R2) was upregulated by NSUN2-mediated m5C methylation by enhancing its mRNA stabilization and activated the phosphorylation of the PI3K-AKT signaling. The present study explored the underlying mechanism and biological function of NSUN2-meditated m5C RNA methylation in LUAD. NSUN2 was discovered to facilitate the malignancy progression of LUAD through regulating m5C modifications to stabilize PIK3R2 activating the PI3K-AKT signaling, suggesting that NSUN2 could be a novel biomarker and promising therapeutic target for LUAD patients.

Unraveling the Role of RNA-Binding Proteins, with a Focus on RPS5, in the Malignant Progression of Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) represents a major global health concern, demanding a thorough understanding of its molecular mechanisms for effective therapeutic strategies. RNA-binding proteins (RBPs) play critical roles in post-transcriptional gene regulation, with their dysregulation increasingly recognized as a hallmark of various cancers. However, the specific contributions of RBPs to HCC pathogenesis and prevention remain incompletely understood. In this study, we systematically conducted an examination of the expression profiles and clinical relevance of RBPs in 556 clinical samples from well-established cohorts. Through comprehensive analyses, a subset of RBPs exhibiting significant overexpression in HCC was identified, establishing a noteworthy correlation between their aberrant expression and HCC progression. Furthermore, 40S ribosomal protein S5 (RPS5), a ribosomal protein, emerged as a potential key contributor in HCC progression. Rigorous analyses established a correlation between elevated RPS5 expression and advanced clinicopathological features, suggesting its potential as a prognostic biomarker. Experiments further confirmed the impact of RPS5 on pivotal cellular processes implicated in cancer progression, including cell proliferation and metastasis. Further mechanistic studies unveiled the potential of RPS5 to activate the cell cycle by binding to key molecules involved in the pathway, thereby promoting the malignant progression of HCC. Additionally, our analysis of the etiology behind RPS5 overexpression in HCC posited it as an outcome of transcriptional regulation by the transcription factors Nuclear Respiratory Factor 1 (NRF1) and MYC-associated zinc finger protein (MAZ). In conclusion, our study contributes to the growing evidence elucidating the intricate involvement of RBPs, exemplified by RPS5, in the malignant progression of HCC. The integration of genomic, transcriptomic, and functional analyses provides a comprehensive understanding of the regulatory mechanisms associated with RPS5 in HCC. This comprehensive analysis not only advances our knowledge of the molecular drivers behind HCC but also highlights the potential therapeutic relevance of targeting RBPs and their regulatory network for the development of more effective treatment strategies.

Inhibition of demethylase by IOX1 modulates chromatin accessibility to enhance NSCLC radiation sensitivity through attenuated PIF1

Chromatin accessibility is a critical determinant of gene transcriptional expression and regulated by histones modification. However, the potential for manipulating chromatin accessibility to regulate radiation sensitivity remains unclear. Our findings demonstrated that the histone demethylase inhibitor, 5-carboxy-8-hydroxyquinoline (IOX1), could enhance the radiosensitivity of non-small cell lung cancer (NSCLC) in vitro and in vivo. Mechanistically, IOX1 treatment reduced chromatin accessibility in the promoter region of DNA damage repair genes, leading to decreased DNA repair efficiency and elevated DNA damage induced by γ irradiation. Notably, IOX1 treatment significantly reduced both chromatin accessibility and the transcription of phytochrome interacting factor 1 (PIF1), a key player in telomere maintenance. Inhibition of PIF1 delayed radiation-induced DNA and telomeric DNA damage repair, as well as increased radiosensitivity of NSCLC in vitro and in vivo. Further study indicated that the above process was regulated by a reduction of transcription factor myc-associated zinc finger protein (MAZ) binding to the distal intergenic region of the PIF1. Taken together, IOX1-mediated demethylase inactivation reduced chromatin accessibility, leading to elevated telomere damage which is partly due to PIF1 inhibition, thereby enhancing NSCLC radiosensitivity.

Myc-Associated Zinc Finger Protein Promotes Metastasis of Papillary Thyroid Cancer.

Myc-associated zinc finger protein (MAZ) plays a role in cancer progression and metastasis. However, the role and underlying molecular mechanism of MAZ in thyroid cancer have not yet been fully elucidated. This study aimed to explore the clinical significance of MAZ in thyroid cancer tissues, and clarify its mechanism in the occurrence and development of thyroid cancer. The expression level of MAZ protein in thyroid cancer tissues was detected by bioinformatics analysis and immunohistochemistry (IHC). The relationship between the expression level of MAZ and clinicopathological characteristics of thyroid cancer patients was analyzed by multivariate logistic regression analysis. Quantitative reverse-transcription polymerase chain reaction (RT-qPCR) was used to detect the mRNA expression level of MAZ in thyroid cancer cell lines. After MAZ knockdown cell lines were constructed, wound healing and Transwell assays were used to detect the migratory and invasive abilities of cancer cells. The results of IHC showed that the expression level of MAZ protein in thyroid cancer tissues was higher than that in normal adjacent thyroid tissues (p < 0.05), which was consistent with the high expression level of MAZ in thyroid cancer tissues found in The Cancer Genome Atlas (TCGA) database. The results of multivariate logistic regression analysis indicated that the expression level of MAZ was correlated with tumor diameter and tumor capsule of thyroid cancer patients. Moreover, patients with the high MAZ expression level had shorter overall and disease-free survival compared with thyroid cancer patients with the low MAZ expression level (p < 0.05). Further cell function assays indicated that downregulation of MAZ expression level could inhibit the migration and invasion of thyroid cancer cell lines. Moreover, the expression level of epithelial-mesenchymal transition (EMT)-related factor fibronectin 1 (FN1) was obtained from the RNA-seq of MAZ knockdown in thyroid cancer cells. RT-qPCR confirmed that the expression level of FN1 was elevated in MAZ knockdown cell lines (p < 0.05). Bioinformatics analysis indicated that the expression level of FN1 was upregulated in thyroid cancer tissues and had a negative relationship with the expression level of MAZ, as evidenced by correlation analysis. A high expression level of MAZ in thyroid cancer tissues was associated with a poor prognosis of patients. MAZ could affect the progression of thyroid cancer by inducing the EMT process.

TBK1 promotes thyroid cancer progress by activating the PI3K/Akt/mTOR signaling pathway.

Thyroid cancer has received increasing attention; however, its detailed pathogenesis and pathological processes remain unclear. We investigated the role of TANK-binding kinase 1 (TBK1) in the progression of thyroid cancer. The expression of TBK1 in thyroid cancer and normal control tissues was analyzed using real-time quantitative polymerase chain reaction. The function of TBK1 on thyroid cancer cells was detected using MTT, colony formation, wound healing, and Transwell assays. The xenograft assay was carried out to check on the role of TBK1 in thyroid cancer. TBK1 was highly expressed in thyroid tumors. High expression of TBK1 raised viability, proliferation, migration, and invasion of thyroid cancer cells. Gene set enrichment analysis revealed that TBK1 activated the phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin pathway. In addition, Myc-associated zinc finger protein (MAZ) was overexpressed in thyroid cancer and transcriptionally activated BK1. MAZ silence reversed the effects of TBK1 overexpression on thyroid cancer progression. Cotransfection with MAZ small-interfering RNA(siRNA) and TBK1 siRNA did not strengthen the inhibitory effect of TBK1 silencing on the thyroid cancer cells. The xenograft tumor assay showed that TBK1 short hairpinRNA inhibited tumor growth. MAZ silencing inhibited tumor progress of thyroid cancer cells, whereas this inhibitory effect was reversed by TBK1 overexpression.

Comprehensive analysis of the tumor-promoting effect and immune infiltration correlation MAZ from pan-cancer to hepatocellular carcinoma.

Myc-associated zinc-finger protein (MAZ) is a transcription factor, which has been confirmed to be abnormally expressed in many tumors and involved in regulating the proliferation, migration, apoptosis, and autophagy of tumor cells. Currently, there is a lack of comprehensive analysis of MAZ in pan-cancer, and the mechanism of MAZ in hepatocellular carcinoma (HCC) and its association with immunotherapy remains unclear. The expression, prognostic mutation, sCNA, and tumor immunity characteristics of MAZ in 33 types of tumors were analyzed by The Cancer Genome Atlas (TCGA), GEPIA, and TIMER databases. The association of MAZ expression levels with drug sensitivity, immunotherapy, immune checkpoints, and HLA-associated genes was further analyzed. Transwell, CCK-8, wound healing, and flow cytometry verified that MAZ affected the malignant cell behavior of HCC. The signaling pathways and cellular functions affected by MAZ in HCC were revealed by GSEA enrichment analysis. The expression level of MAZ was up-regulated, and the high expression of MAZ indicated a high-risk prognostic factor in most tumors, including ACC, BLCA, KIRP, LIHC, PRAD, SKCM, and THCA (p<0.05). MAZ expression was positively correlated with the sensitivity of most chemotherapy drugs (p<0.05). HLA-DQB2, HLA-H, and most immune checkpoint genes were remarkably up-regulated in the high MAZ expression group (p<0.05). GSEA analysis revealed that MAZ expression was highly correlated with the intracellular immune-related functions and cancer-related signaling pathway, including the B cell receptor signaling pathway, complement activation, humoral immune response, TGF-β signaling pathway, and Wnt signaling pathway. The overexpression of MAZ in HCC cells could promote the abilities of cell proliferation and migration and inhibit tumor cell apoptosis. Our study revealed that MAZ might play a role in promoting the progression of HCC. It was closely related to the tumor microenvironment, immune cell infiltration, and immune escape in pan-cancer. Moreover, this study provides new insights into MAZ as a prognostic marker and potential therapeutic target in HCC.

TUG1/MAZ/FTH1 Axis Attenuates the Antiglioma Effect of Dihydroartemisinin by Inhibiting Ferroptosis.

Glioma is the most common primary intracranial malignant tumor in the brain. Currently, due to the limited treatment methods, the clinical outcome of patients with standard surgery combined with radiotherapy and chemotherapy is not satisfactory. Therefore, we urgently need to develop effective drugs to solve this problem. As a semisynthetic derivative of artemisinin, dihydroartemisinin (DHA) has been proved to have antitumor activity in glioma, which can induce apoptosis and inhibit the proliferation, migration, and invasion of glioma cells. In recent years, ferroptosis has been identified as another antitumor mechanism of DHA. Researchers have shown that DHA could promote ferroptosis in glioma cells. However, the specific molecular mechanisms of ferroptosis induced by DHA need more exploration. In this study, we found DHA could induce ferroptosis with ROS production and lipid peroxidation in glioma cells. Low expression of GPX4 and high expression of HMOX1 were identified in DHA treated glioma cells. Surprisingly, we found FTH1, a negative regulator of ferroptosis, upregulated in DHA treated glioma cells. It indicated that there should be some mechanisms that may cause ferroptosis attenuation in DHA treated glioma cells. For the first time, we confirmed that MYC-associated zinc finger protein (MAZ) could actively regulate FTH1 by binding to FTH1 promoter by CHIP assay. MAZ was further identified as the direct target of long noncoding RNA (lncRNA) TUG1 through luciferase assay. Downregulated expression of TUG1 and upregulated expression of MAZ were identified in DHA treated glioma cells. TUG1 overexpression or inhibition of FTH1 expression could enhance the antiglioma effect of DHA in vitro and in vivo, providing a promising strategy to enhance the antitumor effect of DHA in glioma.

Abstract 778: Dysregulation of alternative mRNA splicing by oncogenic KRAS in lung adenocarcinoma

Abstract Alternative mRNA splicing is dysregulated in many cancers including lung adenocarcinoma. These aberrant splicing events can sometimes be explained by mutations in splice sites or splicing factors. However, the majority of mis-splicing in cancers remains unexplained. We hypothesize that oncogenic signaling pathways play a role in regulating alternative splicing. In this study, we focus on mRNA splicing activity regulated by the Ras signaling cascade, which is frequently mutated in cancers. These pathways offer avenues for therapeutic modulation through small molecule inhibitors.We took a global proteomic and transcriptomic approach to study the effects of oncogenic Ras signaling on RNA splicing in vitro. Specifically, we performed LC-MS/MS and RNA-seq profiling on normal human lung airway epithelial (AALE) cells overexpressing wild-type or mutant KRAS or RIT1 (N = 3 replicates per allele). Phosphorylation of splicing factors was preferentially downregulated in KRASmut cells compared to KRASWT cells, suggesting that oncogenic KRAS signaling regulates splicing factor activity. Additionally, of the 2227 and 2452 skipped exon (SE) events in KRASG12V and KRASQ61H cells, respectively, compared to KRASWT overexpressing cells, 1013 events were shared between the two mutants. This statistically significant overlap (p &amp;lt; 0.001, hypergeometric test) indicates that KRAS has a role in splicing regulation that is disrupted when the protein is mutated. To determine how KRAS-regulated splicing activity compared to other signaling proteins and oncogenes, we also profiled the whole transcriptomes of isogenic A549 lung adenocarcinoma cell lines overexpressing 86 wild-type or variant alleles across 27 genes implicated in lung cancers (N = 4 to 8 replicates per allele). Of all pairs of mutant and wild-type alleles tested, KRASmut cells compared to KRASWT overexpressing cells exhibited the second highest levels of alternative splicing, behind only RNA binding protein RBM45 and its mutant allele RBM45M126I. In particular, ten SE events were observed to be differentially regulated in a KRAS dependent manner in both AALE and A549 cells. One of these 10 events is the differential splicing of the Myc Associated Zinc Finger (MAZ) protein to increase the expression of its splice variant that acts as a negative regulator of transcription. As MAZ regulates expression of KRAS, this splice variant may be a mechanism for the cell to modulate wild-type KRAS levels in the presence of KRAS mutants. Our proteomic and transcriptomic profiling in lung epithelial and lung adenocarcinoma cells uncovers splicing factor activity and mRNA splicing events regulated by oncogenic KRAS. With further studies of the alternative splicing events described, it will be possible to design or repurpose therapies in order to target aberrant splicing caused by disrupted Ras signaling and its downstream effectors. Citation Format: April Lo, Maria McSharry, Alice H. Berger. Dysregulation of alternative mRNA splicing by oncogenic KRAS in lung adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 778.

Identification of Common Hub Genes in Human Dermal Fibroblasts Stimulated by Mechanical Stretch at Both the Early and Late Stages.

BackgroundMechanical stretch is vital for soft tissue regeneration and development and is utilized by plastic surgeons for tissue expansion. Identifying the common hub genes in human dermal fibroblasts (HDFs) stimulated by mechanical stretch at different stages will help elucidate the mechanisms involved and improve the efficiency of tissue expansion.MethodsA gene expression dataset (GSE58389) was downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) in HDFs between cyclic mechanical stretching and static samples were identified at 5 and 24 h. Common DEGs overlapped in both the 5 h and 24 h groups. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to determine the functions of the DEGs. Protein-protein interaction networks were constructed using the STRING database. The top 10 hub genes were selected using the plug-in Cytohubba within Cytoscape. The regulatory network of hub genes was predicted using NetworkAnalyst.ResultsA total of 669 and 249 DEGs were identified at the early (5 h) and late stages (24 h), respectively. Of these, 152 were present at both stages and were designated as common DEGs. The top enriched GO terms were “regulation of autophagy” at the early stage, and “sterol biosynthetic processes” at the late stage. The top KEGG terms were “pyrimidine metabolism” and “synaptic vesicle cycle” at the early and late stages, respectively. Seven common DEGs [DEAD-box helicase 17 (DDX17), exocyst complex component 7 (EXOC7), CASK interacting protein 1 (CASKIN1), ribonucleoprotein PTB-binding 1 (RAVER1), late cornified envelope 1D (LCE1D), LCE1C, and polycystin 1, transient receptor potential channel interacting (PKD1)] and three common DEGs [5′-3′ exoribonuclease 2 (XRN2), T-complex protein 1 (TCP1), and syntaxin 3 (STX3)] were shown to be upregulated and downregulated hub genes, respectively. The GO terms of the common hub genes were “skin development” and “mRNA processing.” After constructing the regulatory network, hsa-mir-92a-3p, hsa-mir-193b-3p, RNA polymerase II subunit A (POLR2A), SMAD family member 5 (SMAD5), and MYC-associated zinc finger protein (MAZ) were predicted as potential targets in both stages.ConclusionAt the early stage, there were clear changes in gene expression related to DNA and chromatin alterations; at late stages, gene expression associated with cholesterol metabolism was suppressed. Common DEGs related to skin development, transcriptional regulation, and cytoskeleton rearrangement identified in both stages were found to be potential targets for promoting HDF growth and alignment under mechanical stretch.

CRISPR and biochemical screens identify MAZ as a cofactor in CTCF-mediated insulation at Hox clusters

CCCTC-binding factor (CTCF) is critical to three-dimensional genome organization. Upon differentiation, CTCF insulates active and repressed genes within Hox gene clusters. We conducted a genome-wide CRISPR knockout (KO) screen to identify genes required for CTCF-boundary activity at the HoxA cluster, complemented by biochemical approaches. Among the candidates, we identified Myc-associated zinc-finger protein (MAZ) as a cofactor in CTCF insulation. MAZ colocalizes with CTCF at chromatin borders and, similar to CTCF, interacts with the cohesin subunit RAD21. MAZ KO disrupts gene expression and local contacts within topologically associating domains. Similar to CTCF motif deletions, MAZ motif deletions lead to derepression of posterior Hox genes immediately after CTCF boundaries upon differentiation, giving rise to homeotic transformations in mouse. Thus, MAZ is a factor contributing to appropriate insulation, gene expression and genomic architecture during development.

Roles of Myc-associated zinc finger protein in malignant tumors.

As an important transcription factor that is widely expressed in most tissues of the human body, Myc-associated zinc finger protein (MAZ) has been reported highly expressed in many malignant tumors and thought to be a promising therapeutic target for cancer treatment. In this review, we aim to offer a comprehensive understanding of MAZ regulation in malignant tumors. The carboxy terminal of MAZ protein contains six C2H2 zinc fingers, and its regulation of transcription is based on the interaction between the GC-rich DNA binding sites of target genes and its carboxy-terminal zinc finger motifs. MAZ protein has been found to activate or inhibit the transcriptional initiation process of many target genes, as well as play an important role in the transcriptional termination process of some target genes, so MAZ poses dual regulatory functions in the initiation and termination process of gene transcription. Through the transcriptional regulation of c-myc and Ras gene family, MAZ poses an important role in the occurrence and development of breast cancer, pancreatic cancer, prostate cancer, glioblastoma, neuroblastoma, and other malignant tumors. Our review shows a vital role of MAZ in many malignant tumors and provides novel insight for cancer diagnosis and treatment.

SIPL1, Regulated by MAZ, Promotes Tumor Progression and Predicts Poor Survival in Human Triple-Negative Breast Cancer.

BackgroundTriple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer owing to a lack of effective targeted therapy and acquired chemoresistance. Here, we explored the function and mechanism of shank-interacting protein-like 1 (SIPL1) in TNBC progression.MethodsSIPL1 expression was examined in human TNBC tissues and cell lines by quantitative reverse transcription PCR, western blot, and immunohistochemistry. SIPL1 overexpression and silenced cell lines were established in BT-549 and MDA-MB-231 cells. The biological functions of SIPL1 in TNBC were studied in vitro using the CCK-8 assay, CellTiter-Glo Luminescent Cell Viability assay, caspase-3/8/9 assay, wound healing assay, and transwell assay and in vivo using a nude mouse model. The potential mechanisms underlying the effects of SIPL1 on TNBC progression were explored using bioinformatics analysis, luciferase reporter assays, and chromatin immunoprecipitation followed by qPCR.Results SIPL1 expression was higher in human TNBC tissues and cell lines than in adjacent normal tissues and a breast epithelial cell line (MCF10A). High expression of SIPL1 was positively correlated with poor overall and disease-free survival in patients with TNBC. SIPL1 overexpression elevated and SIPL1 silencing repressed the malignant phenotypes of TNBC cells in vitro. SIPL1 overexpression promoted xenograft tumor growth in vivo. Myc-associated zinc-finger protein (MAZ) transcriptionally activated SIPL1. Finally, we found that SIPL1 promoted TNBC malignant phenotypes via activation of the AKT/NF-κB signaling pathways.ConclusionsThese results indicate that the MAZ/SIPL1/AKT/NF-κB axis plays a crucial role in promoting the malignant phenotypes of TNBC cells.

Genetic alternations and immune characteristics in patients with small cell lung cancer

Genetic alternations and immune characteristics in patients with small cell lung cancer

Current updates and future perspectives in the evaluation of azoospermia: A systematic review

ABSTRACT Objectives: To provide a summary of the current evaluation of azoospermia and insights into future perspectives in the evaluation and counselling of men with azoospermia. Methods: A search of PubMed, Cochrane Reviews and Web of Science databases was performed for full-text English-language articles published between 1943 and 2020 focussing on ‘future perspectives’, ‘azoospermia’ and ‘evaluation’. Results: Azoospermia represents a severe form of male infertility characterised by sperm production so impaired that there are no sperm present in the ejaculate. The current evaluation of azoospermia focusses on patient history and physical examination with selected adjunctive laboratory investigations including serum hormones, a karyotype and screening for Y chromosome microdeletions. Future diagnostics are focussed on identifying the underlying genetic aetiologies for azoospermia, as well as a greater emphasis on screening for systemic illness that men with severe infertility may be predisposed to develop. Conclusion: Azoospermia represents an extreme form of male infertility, and evaluation relies heavily on history and physical examination, as genetic evaluations for these individuals remain limited. Future evaluation will focus on next-generation sequencing and more rigorous evaluation for possible co-existing and future risk of systemic disease. ABBREVIATIONS: ADGRG2, adhesion G protein-coupled receptor G2; ASRM: American Society of Reproductive Medicine; AZF: azoospermia factor; CBAVD: congenital bilateral absence of the vas deferens; CFTR: cystic fibrosis transmembrane conductance regulator; CRKL: CRK-like proto-oncogene; E2F1: E2F transcription factor 1; HAUS7: HAUS augmin-like complex subunit 7; HR: hazard ratio; KS: Klinefelter syndrome; MAZ, MYC-associated zinc finger protein; NGS: next-generation sequencing; NOA: non-obstructive azoospermia; OA: obstructive azoospermia; RHOX: reproductive homeobox on the X chromosome; SH2: SRC homology 2; TAF7L: TATA-box binding protein associated factor 7-like; TEX11: testis-expressed 11; WES: whole-exome sequencing

Myc-associated zinc-finger protein promotes clear cell renal cell carcinoma progression through transcriptional activation of the MAP2K2-dependent ERK pathway

BackgroundThe dysfunction of myc-related zinc finger protein (MAZ) has been proven to contribute to tumorigenesis and development of multiple cancer types. However, the biological roles and clinical significance of MAZ in clear cell renal carcinoma (ccRCC) remain unclear.MethodsMAZ expression was examined in ccRCC and normal kidney tissue by quantitative real-time PCR and Western blot. Statistical analysis was used to evaluate the clinical correlation between MAZ expression and clinicopathological characteristics to determine the relationship between MAZ expression and the survival of ccRCC patients. The biological roles of MAZ in cells were investigated in vitro using MTT and colony assays. Luciferase reporter assays and chromatin immunoprecipitation (ChIP) were used to investigate the relationship between MAZ and its potential downstream signaling molecules.ResultsMAZ expression is elevated in ccRCC tissues, and higher levels of MAZ were correlated with poor survival of patients with ccRCC. MAZ upregulation elevates the proliferation ability of ccRCC cells in vitro, whereas silencing MAZ represses this ability. Our results further reveal that MAZ promotes cell growth, which is dependent on ERK signaling. Importantly, we found that MAZ positively regulates MAP2K2 expression in ccRCC cells. Mechanistically, MAZ binds to the MAP2K2 promoter and increases MAP2K2 transcription. Furthermore, MAP2K2 levels were shown to be increased in ccRCC tissues and to be associated with a poor prognosis of ccRCC patients. MAP2K2 upregulation activates the ERK signaling pathway and promotes ccRCC progression.ConclusionThese results reveal that the MAZ/MAP2K2/ERK signaling axis plays a crucial role in promoting ccRCC progression, which suggests the potential therapeutic utility of MAZ in ccRCC.

The Myc‐Associated Zinc Finger Protein (MAZ) Controls Cohesin Positioning and Genome Organization Independently OR In Concert With CTCF

The Myc-associated zinc finger protein (MAZ) is a transcription factor that has been shown to regulate transcriptional initiation and termination. However, the underlying mechanisms of MAZ function in the context of chromatin is not fully understood. By applying biochemistry and genetics approaches, we show that MAZ binds to many genomic sites adjacent to the CCCTC-binding factor (CTCF), a protein that is best known for its insulation function in three-dimensional organization of eukaryotic genomes. We demonstrate that, similar to CTCF, MAZ physically interacts with the cohesin subunit Rad21. In addition, we find that MAZ shares with CTCF the ability to independently pause the elongating form of RNA polymerase II, and subsequently affects RNA alternative splicing. Our ChIP-seq analysis of the genome wide distribution of cohesins and CTCF reveals that depletion of CTCF results in preferential loss of CTCF from sites not occupied by MAZ, showing that the binding of both CTCF and cohesin is more stable at the CTCF/MAZ double sites than at the sites occupied by CTCF alone. In an insulation assay like that used for CTCF, we find that binding of MAZ to sites between an enhancer and promoter results in downregulation of reporter gene expression, supporting a role for MAZ as a novel insulator protein. Hi-C analysis indicates that depletion of MAZ in cells not only disrupts local interactions within Topologically associating domains (TADs) but also reduces contacts that establish the boundaries of individual TADs. Taken together, our results suggest that MAZ shares properties with CTCF that allow it to act independently or synergistically in organizing higher order genome architectures, thereby controlling gene expression.

MicroRNA-29b-3p Inhibits the Migration and Invasion of Gastric Cancer Cells by Regulating the Autophagy-Associated Protein MAZ.

PurposeThe purpose of this study was to investigate the relationship between microRNA-29b-3p (miR-29b-3p) and myc-associated zinc finger protein (MAZ) expression and the effects of this interaction on the proliferation, migration, and invasion of gastric cancer cells.MethodsqPCR and Western blots were used to detect the expression of miR-29b-3p and MAZ. The dual luciferase reporter gene system was used to explore whether MAZ is the target of miR-29b-3p. Cell function experiments and a mouse tumorigenesis model were used to determine the effects of miR-29b-3p overexpression and MAZ depletion on proliferation, migration, and invasion in gastric cancer cell lines and on tumor growth.ResultsThe expression level of miR-29b-3p was low and the expression level of MAZ was high in gastric cancer cells compared with normal human gastric mucosal epithelial cells. MAZ was the target gene of miR-29b-3p. The upregulation of miR-29b-3p reduces the expression of MAZ. Overexpression of miR-29b-3p and downregulation of MAZ inhibited the proliferation and migration of cancer cells and induced apoptosis by controlling the expression of autophagy-related proteins. MiR-29b-3p mimics inhibit tumor growth in mice.ConclusionMiR-29b-3p inhibits the migration and invasion of gastric cancer cells by regulating the autophagy-related protein MAZ.