MCM6 indicates adverse tumor features and poor outcomes and promotes G1/S cell cycle progression in neuroblastoma

Identifying genetic overlaps in obesity and metabolic disorders unlocking unique and shared mechanistic insights

OBJECTIVE

Obesity has a high heritability and frequently co-occurs with metabolic disorders, indicating shared genetic susceptibility. The underlying causative genes and biological mechanisms of obesity and metabolic disorders remain predominantly elusive.

METHODS

The FinnGen R11 dataset, including over 450,000 subjects, was employed in conjunction with the Genotype-Tissue Expression Project (GTEx) v8 eQTls dataset to conduct cross-tissue transcriptome association studies, Functional Summary-based Imputation in single tissues, and Gene Analysis combined with Multimarker Analysis of Genomic Annotation, respectively, for identifying distinct and shared genetic architectures of obesity and metabolic disorders. We also employed RHOGE to ascertain the genetic correlation and putative causal directions between them. Subsequent Mendelian randomization, colocalization analyses, and other cell and tissue enrichment analyses were employed to enhance our understanding of the functional implications of these susceptibility genes.

RESULTS

A total of 35 genes were identified as obesity susceptibility and 10 genes linked to metabolic disorder susceptibility. Of these, three genes (MCM6, MAPRE3 and UBXN4) were identified as being shared. Mendelian randomization and colocalization analyses revealed the three shared genes have causal associations with obesity and metabolic disorders and serve as independent signals. Subsequent analyses indicated MCM6 may influence obesity and metabolic disorder risk by regulating DNA replication, cell proliferation, and interactions with chemical responses. MAPRE3 may confer protective effects against obesity and metabolic disorders through PAK Pathway, while UBXN4 may involve in regulating cholesterol metabolism.

CONCLUSION

Our study provides insight into the novel shared genetic mechanism between obesity and metabolic disorders and identifies potential targets for pharmacological intervention.

PHD-2/HIF-1α axis mediates doxorubicin-induced angiogenesis in SH-SY5Y neuroblastoma microenvironment: a potential survival mechanism

The response of neuroblastoma (NB) cells to chemotherapeutics and their influence on NB microenvironment remain incompletely understood. Herein, we examined the underlying molecular mechanism via which Doxorubicin, a chemotherapeutic agent used for NB treatment, promotes proangiogenic response in the SH-SY5Y microenvironment. Doxorubicin treatment at 1 µg/ml reduced SH-SY5Y cell proliferation and primed the apoptosis pathway. Unexpectedly, SH-SY5Y cells treated with doxorubicin upregulated their expression of the pro-angiogenic factors, including vascular endothelial growth factor (VEGF), platelets-derived growth factor (PDGF), and matrix metalloprotease-2 (MMP-2) and secretion of nitric oxide. To assess the functional angiogenesis of SH-SY5Y cells pre-treated with doxorubicin, an indirect co-culture system with human umbilical vein endothelial cells (HUVEC) was established. These HUVECs acquired enhanced proliferation, migration capacity, and tube formation capability and exhibited increased nitric oxide (NO) production, in addition to upregulated α-smooth muscle actin expression, suggesting enhanced contractility. In-ovo studies of the neo-angiogenic response of SH-SY5Y pre-treated with doxorubicin further show their promoted neo-angiogenesis as indicated by the generated blood vessels and histological analysis of CD31 expression. Inhibition of PHD-2 could be a potential target for doxorubicin, as indicated by molecular docking, molecular dynamics (MD) simulation, and MM-GBSA calculations, leading to hypoxia-inducible factor-1 alpha (HIF-1α) stabilization. Bioinformatics analyses and enrichment analyses of RNA-seq data revealed activation of Pi3K pathway which is further validated in-vitro. These results provide evidence of the unexpected pro-angiogenic response of SH-SY5Y cells to doxorubicin treatment and suggest the potential use of multi-modal therapeutic regimens for a more comprehensive approach to NB treatment.

The MCM6-c-Myc positive feedback loop mediates bladder cancer progression and cisplatin resistance

Chemotherapy remains a cornerstone in the treatment of bladder cancer (BLCA); however, the development of chemoresistance substantially limits its efficacy and significantly affects patient survival. Thus, elucidating the molecular mechanisms underlying BLCA chemoresistance is critical to improving patient outcomes. Our study identified MCM6 as an oncogene that facilitates BLCA proliferation and invasion and is linked to cisplatin resistance. Further analysis demonstrated that MCM6 is upregulated in BLCA tissues with poor chemotherapy response. Moreover, MCM6 knockdown enhanced cisplatin sensitivity in BLCA cells both in vitro and in vivo, indicating that MCM6 is a key driver of cisplatin resistance. Mechanistically, MCM6 contributes to cisplatin resistance by enhancing DNA damage repair (DDR). Knockdown of MCM6 reduced nuclear c-Myc levels and promoted its ubiquitin-mediated degradation, thereby increasing DNA damage. Conversely, c-Myc, as a transcription factor, binds to the MCM6 promoter and promotes its transcription, thereby regulating MCM6 expression. Our findings suggest that targeting MCM6-mediated DDR represents a promising strategy to overcome cisplatin resistance in BLCA.

Expression evaluated by digital image analysis techniques of PRAME more than MCM6 is associated with poor prognosis in neuroblastoma: A pilot study with 84 cases

Neuroblastoma is a common childhood tumor originating from neural crest progenitors with variable clinical behavior. Despite improved overall survival, factors such as stage, histoprognosis, MYCN status, and age still influence outcome. MCM6 regulates DNA replication and contributes to cancer progression. PRAME, first identified in melanoma, also acts on cell replication, epithelial-mesenchymal transition, and cell migration and has been associated with poor outcomes in several cancers, including neuroblastoma, using molecular biology techniques. The study aims to investigate MCM6 and PRAME expression and prognostic roles in neuroblastoma. A retrospective study was conducted, which included data of 84 patients with neuroblastoma diagnosed between 2000 and 2022, sourced from the pediatric tumor registry. Patient's characteristics and prognostic tumor factors were collected. Expression of MCM6 and PRAME proteins was evaluated using digital image analysis techniques. Univariate and multivariate analyses were performed using Cox regression to assess the impact of protein expression on survival and their associations with these prognostic factors. A total of 84 children diagnosed with neuroblastoma were included. MCM6 and PRAME were associated with unfavorable histologies (p = 0.03). PRAME was associated with bone marrow metastases (p < 0.01), high mitotic-karyorrhectic index (p = 0.04), and poor histoprognosis (p < 0.01). PRAME and MCM6 expression was correlated with several neuroblastoma prognostic factors. PRAME was significantly (p = 0.05) associated with poor event-free survival (EFS) and not significantly (p = 0.08) associated with overall survival (OS). Although statistical significance was not reached in multivariate analysis, the trends strongly suggested that the overexpression of MCM6 and PRAME was correlated with decreased survival.

Proliferating CLL cells express high levels of CXCR4 and CD5

Chronic lymphocytic leukemia (CLL) is an incurable progressive malignancy of CD5+ B cells with a birth rate between 0.1% and 1% of the entire clone per day. However, the phenotype and functional characteristics of proliferating CLL cells remain incompletely understood. Here, we stained peripheral blood CLL cells for ki67 and DNA content and found that CLL cells in G1-phase have a CXCR4loCD5hi phenotype, while CLL cells in S/G2/M-phase express high levels of both CXCR4 and CD5. Induction of proliferation in vitro using CD40L stimulation results in high ki67 levels in CXCR4loCD5hi cells with CXCR4 expression increasing as CLL cells progress through S and G2/M-phases, while CXCR4hiCD5lo CLL cells remained quiescent. Dye dilution experiments revealed an accumulation of Ki67hi-divided cells in the CXCR4hiCD5hi fraction. In Eµ-TCL1 transgenic mice, the CXCR4hiCD5hi fraction expressed high levels of ki67 and was expanded in enlarged spleens of diseased animals. Human peripheral blood CXCR4hiCD5hi CLL cells express increased levels of IgM and the chemokine receptors CCR7 and CXCR5 and migrate efficiently toward CCL21. We found higher levels of CXCR4 in patients with progressive disease and the CXCR4hiCD5hi fraction was expanded upon clinical relapse. Thus, this study defines the phenotype and functional characteristics of dividing CLL cells identifying a novel subclonal population that underlies CLL pathogenesis and may drive clinical outcomes.

Identification of functional circRNAs regulating ovarian follicle development in goats

BARKGROUND

Circular RNAs (circRNAs) play important regulatory roles in a variety of biological processes in mammals. Multiple birth-traits in goats are affected by several factors, but the expression and function of circRNAs in follicular development of goats are not clear. In this study, we aimed to investigate the possible regulatory mechanisms of circRNA and collected five groups of large follicles (Follicle diameter > 6 mm) and small follicles (1 mm < Follicle diameter < 3 mm) from Leizhou goats in estrus for RNA sequencing.

RESULTS

RNA sequencing showed that 152 circRNAs were differentially expressed in small and large follicles. Among them, 101 circRNAs were up-regulated in large follicles and 51 circRNAs were up-regulated in small follicles. GO and KEGG enrichment analyses showed that parental genes of the differential circRNAs were significantly enriched in important pathways, such as ovarian steroidogenesis, GnRH signaling pathway, animal autophagy and oxytocin signalling pathway. BioSignal analysis revealed that 152 differentially expressed circRNAs could target 91 differential miRNAs including miR-101 family (chi-miR-101-3p, chi-miR-101-5p), miR-202 family (chi-miR-202-5p, chi-miR-202-3p),60 circRNAs with translation potential. Based on the predicted sequencing results, the ceRNA networks chicirc_008762/chi-miR-338-3p/ARHGAP18 and chicirc_040444/chi-miR-338-3p/STAR were constructed in this study. Importantly, the new gene circCFAP20DC was first discovered in goats. The EDU assay and flow cytometry results indicated that circCFAP20DC enhanced the proliferation of follicular granulosa cells(GCs). Real-time quantitative PCR and western blotting assays showed that circCFAP20DC activated the Retinoblastoma(RB) pathway and promoted the progression of granulosa cells from G1 to S phase.

CONCLUSION

Differential circRNAs in goat size follicles may have important biological functions for follicular development. The novel gene circCFAP20DC activates the RB pathway, promoting the progression of GCs from G1 to S phase. This, in turn, enhances the proliferation of follicular GCs in goats.

Probing the metalloproteome: an 8-mercaptoquinoline motif enriches minichromosome maintenance complex components as significant metalloprotein targets in live cells

Affinity-based probes are valuable tools for detecting binding interactions between small molecules and proteins in complex biological environments. Metalloproteins are a class of therapeutically significant biomolecules which bind metal ions as part of key structural or catalytic domains and are compelling targets for study. However, there is currently a limited range of chemical tools suitable for profiling the metalloproteome. Here, we describe the preparation and application of a novel, photoactivatable affinity-based probe for detection of a subset of previously challenging to engage metalloproteins. The probe, bearing an 8-mercaptoquinoline metal chelator, was anticipated to engage several zinc metalloproteins, including the 26S-proteasome subunit Rpn11. Upon translation of the labelling experiment to mammalian cell lysate and live cell experiments, proteomic analysis revealed that several metalloproteins were competitively enriched. The diazirine probe SMK-24 was found to effectively enrich multiple components of the minichromosome maintenance complex, a zinc metalloprotein assembly with helicase activity essential to DNA replication. Cell cycle analysis experiments revealed that HEK293 cells treated with SMK-24 experienced stalling in G0/G1 phase, consistent with inactivation of the DNA helicase complex. This work represents an important contribution to the library of cell-permeable chemical tools for studying a collection of metalloproteins for which no previous probe existed.

MCM6 Inhibits Decidualization via Cross-Talking with ERK Pathway in Human Endometrial Stromal Cells

Decidualization plays an important role in the implantation of the embryo, but the molecular action implicated in this process is not completely known. Herein, we found that, compared with the proliferative endometrial tissues, the expression of minichromosome maintenance complex component 6 (MCM6) was markedly decreased in the secretory endometrial tissues. To verify the function of MCM6 in decidualization, in vitro decidualization model was constructed by treating human endometrial stromal cells (HESCs) with estrogen (E2) and progesterone (P4). Consistently, MCM6 level was downregulated in E2P4-treated HESCs. Administration of E2P4 accumulated HESCs in G1 cell cycle phase, leading to cell growth suppression. Ectopic expression of MCM6 promoted the transition of G1/S and restored the proliferation of HESCs that were inhibited by E2P4. MCM6 overexpression led to aberrant activation of extracellular signal-regulated kinase (ERK) and treatment with ERK agonist Ro 67-7476 restored MCM6 expression and cell proliferation inhibited by E2P4. Our data suggested that MCM6/ERK feedback loop plays a negative role in E2P4-induced decidualization and implies that MCM6 may be a promising target for meliorating uterine receptivity.

In silico functional, structural and pathogenicity analysis of missense single nucleotide polymorphisms in human MCM6 gene

Single nucleotide polymorphisms (SNPs) are one of the most common determinants and potential biomarkers of human disease pathogenesis. SNPs could alter amino acid residues, leading to the loss of structural and functional integrity of the encoded protein. In humans, members of the minichromosome maintenance (MCM) family play a vital role in cell proliferation and have a significant impact on tumorigenesis. Among the MCM members, the molecular mechanism of how missense SNPs of minichromosome maintenance complex component 6 (MCM6) contribute to DNA replication and tumor pathogenesis is underexplored and needs to be elucidated. Hence, a series of sequence and structure-based computational tools were utilized to determine how mutations affect the corresponding MCM6 protein. From the dbSNP database, among 15,009 SNPs in the MCM6 gene, 642 missense SNPs (4.28%), 291 synonymous SNPs (1.94%), and 12,500 intron SNPs (83.28%) were observed. Out of the 642 missense SNPs, 33 were found to be deleterious during the SIFT analysis. Among these, 11 missense SNPs (I123S, R207C, R222C, L449F, V456M, D463G, H556Y, R602H, R633W, R658C, and P815T) were found as deleterious, probably damaging, affective and disease-associated. Then, I123S, R207C, R222C, V456M, D463G, R602H, R633W, and R658C missense SNPs were found to be highly harmful. Six missense SNPs (I123S, R207C, V456M, D463G, R602H, and R633W) had the potential to destabilize the corresponding protein as predicted by DynaMut2. Interestingly, five high-risk mutations (I123S, V456M, D463G, R602H, and R633W) were distributed in two domains (PF00493 and PF14551). During molecular dynamics simulations analysis, consistent fluctuation in RMSD and RMSF values, high Rg and hydrogen bonds in mutant proteins compared to wild-type revealed that these mutations might alter the protein structure and stability of the corresponding protein. Hence, the results from the analyses guide the exploration of the mechanism by which these missense SNPs of the MCM6 gene alter the structural integrity and functional properties of the protein, which could guide the identification of ways to minimize the harmful effects of these mutations in humans.

Systematic analysis of expression and prognostic significance for MCM family in head and neck squamous cell carcinoma

BACKGROUND

Head and neck squamous cell carcinoma (HNSC) is a common malignant tumor in the world and has a poor prognosis. The family of minichromosome maintenance proteins (MCM) improves the stability of genome replication by inhibiting the rate of DNA replication in eukaryotic cells, thus, small changes in physiological MCM levels would increase the instability of gene replication and increase the incidence of tumor formation, most of which are significantly elevated in multiple cancers. However, the expression of different MCM families in HNSC and their prognostic value remain unclear.

METHODS

ONCOMINE and GEPIA databases were used to analyze the expression of MCMs in HNSC. The Kaplan-Meier plotter database was used to identify molecules with prognostic values. We collected 77 HNSC tissues and 50 normal tissues to validate the results of the bioinformatics analysis by immunohistochemical staining.

RESULTS

The expression of MCM3, MCM5 and MCM6 in mRNA and protein levels were higher in HNSC. Moreover, the increased expression of MCM3, MCM5 and MCM6 in mRNA and protein levels predicted better prognosis of HNSC patients. Furthermore, multivariate analysis showed that high expressions of MCM3, MCM5 and MCM6 in protein level may be independent prognostic factors for HNSC patients.

CONCLUSION

The results of this study indicated that MCM3, MCM5 and MCM6 play an important role in occurrence and development in HNSC and might be risk factors for the survival of HNSC patients.

Identification of the role of MCM6 in bladder cancer prognosis, immunotherapy response, and in vitro experimental investigation using multi-omics analysis

BACKGROUND

The tumor-promoting effects of MCM6 in numerous tumors have been widely revealed, yet its specific role in bladder cancer (BLCA) is still elusive. The objective of this research was to explore the underlying impact of MCM6 on BLCA.

METHODS

Integrating transcriptomic and proteomic data, MCM6 was identified to be strongly correlated with BLCA through weighted gene co-expression network analysis(WGCNA) and venn analyses. Then, the clinical value of MCM6 was validated with public database data. The different molecular/immune characteristics and the benefit of immunotherapy were also found in MCM6-defined subgroups. Additionally, single-cell RNA sequencing (scRNA-seq) data was choose for quantify MCM6 expression in the distinct BLCA cell types. The biological role of MCM6 were evaluated via in vitro functional experiments.

RESULTS

It was testified that the MCM6 could distinguish patients outcome in TCGA and GEO cohorts. Moreover, compared with the MCM6 low-expression group, the MCM6 high-expression group was related to more tumor-promoting related pathways, aggressive phenotypes, and benefit from immunotherapy. Analysis of scRNA-seq data resulted in MCM6 was mainly expressed in BLCA epithelial cells and the proportion of MCM6-expressing tumor epithelial cells is higher than the normal epithelial cells. Moreover, vitro experiments demonstrated that MCM6 knockdown repressed proliferation, cell cycle, migration, and invasion of BLCA cells.

CONCLUSION

This research indicated MCM6 is a promising marker for both prognosis and immunotherapy benefit and could promote the cells proliferation, invasion and migration in BLCA.

Minichromosome maintenance protein family member 6 mediates hepatocellular carcinoma progression by recruiting UBE3A to induce P53 ubiquitination

With limited therapeutic options for hepatocellular carcinoma (HCC), it is of great significance to investigate the underlying mechanisms and identifying tumor drivers. MCM6, a member of minichromosome maintenance proteins (MCMs), was significantly elevated in HCC progression and associated with poor prognosis. Knockdown of MCM6 significantly inhibited the proliferation and migration of HCC cells with the increased apoptosis ratio and cell cycle arrest, whereas overexpression of MCM6 induced adverse effects. Mechanistically, MCM6 could decrease the P53 activity by inducing the degradation of P53 protein. In addition, MCM6 enhanced the ubiquitination of P53 by recruiting UBE3A to form a triple complex. Furthermore, overexpression of UBE3A significantly rescued the P53 activation and suppression of malignant behaviors mediated by MCM6 inhibition. In conclusion, MCM6 facilitated aggressive phenotypes of HCC cells by UBE3A/P53 signaling, providing potential biomarkers and targets for HCC.

P53 status, and G2/M cell cycle arrest, are determining factors in cell-death induction mediated by ELF-EMF in glioblastoma

The average survival of patients with glioblastoma is 12-15 months. Therefore, finding a new treatment method is important, especially in cases that show resistance to treatment. Extremely low-frequency electromagnetic fields (ELF-EMF) have characteristics and capabilities that can be proposed as a new cancer treatment method with low side effects. This research examines the antitumor effect of ELF-EMF on U87 and U251 glioblastoma cell lines. Flowcytometry determined the viability/apoptosis and distribution of cells in different phases of the cell cycle. The size of cells was assessed by TEM. Important cell cycle regulation genes mRNA expression levels were investigated by real-time PCR. ELF-EMF induced apoptosis in U87cells much more than U251 (15% against 2.43%) and increased G2/M cell population in U87 (2.56%, p value < 0.05), and S phase in U251 (2.4%) (data are normalized to their sham exposure). The size of U87 cells increased significantly after ELF-EMF exposure (overexpressing P53 in U251 cells increased the apoptosis induction by ELF-EMF). The expression level of P53, P21, and MDM2 increased and CCNB1 decreased in U87. Among the studied genes, MCM6 expression decreased in U251. Increasing expression of P53, P21 and decreasing CCNB1, induction of cell G2/M cycle arrest, and consequently increase in the cell size can be suggested as one of the main mechanisms of apoptosis induction by ELF-EMF; furthermore, our results demonstrate the possible footprint of P53 in the apoptosis induction by ELF-EMF, as U87 carry the wild type of P53 and U251 has the mutated form of this gene.

De novo MCM6 variants in neurodevelopmental disorders: a recognizable phenotype related to zinc binding residues

The minichromosome maintenance (MCM) complex acts as a DNA helicase during DNA replication, and thereby regulates cell cycle progression and proliferation. In addition, MCM-complex components localize to centrosomes and play an independent role in ciliogenesis. Pathogenic variants in genes coding for MCM components and other DNA replication factors have been linked to growth and developmental disorders as Meier-Gorlin syndrome and Seckel syndrome. Trio exome/genome sequencing identified the same de novo MCM6 missense variant p.(Cys158Tyr) in two unrelated individuals that presented with overlapping phenotypes consisting of intra-uterine growth retardation, short stature, congenital microcephaly, endocrine features, developmental delay and urogenital anomalies. The identified variant affects a zinc binding cysteine in the MCM6 zinc finger signature. This domain, and specifically cysteine residues, are essential for MCM-complex dimerization and the induction of helicase activity, suggesting a deleterious effect of this variant on DNA replication. Fibroblasts derived from the two affected individuals showed defects both in ciliogenesis and cell proliferation. We additionally traced three unrelated individuals with de novo MCM6 variants in the oligonucleotide binding (OB)-fold domain, presenting with variable (neuro)developmental features including autism spectrum disorder, developmental delay, and epilepsy. Taken together, our findings implicate de novo MCM6 variants in neurodevelopmental disorders. The clinical features and functional defects related to the zinc binding residue resemble those observed in syndromes related to other MCM components and DNA replication factors, while de novo OB-fold domain missense variants may be associated with more variable neurodevelopmental phenotypes. These data encourage consideration of MCM6 variants in the diagnostic arsenal of NDD.

Benvitimod inhibits MCM6-meditated proliferation of keratinocytes by regulating the JAK/STAT3 pathway

BACKGROUND

Benvitimod (Tapinarof), as a small-molecule topical therapeutical aryl hydrocarbon receptor (AHR)-modulating agent, is in clinical development for treating psoriasis and atopic dermatitis. Benvitimod reduces proinflammatory cytokines in psoriasis by specifically binding and activation of AHR. However, whether benvitimod can inhibit keratinocyte proliferation remains unclear. Minichromosome maintenance protein 6 (MCM6) is a key element of the prereplication complex (pre-RC) assembly which is one of the essential steps in the initiation of DNA replication for cell proliferation.

OBJECTIVES

This study aimed to determine whether benvitimod could reduce the excessive proliferation of psoriatic keratinocytes by inhibiting MCM6.

METHODS

We examined the inhibitory effect of benvitimod on MCM6-mediated proliferation of keratinocytes by HaCaT cells in vitro and an IMQ-induced psoriatic model of mice in vivo.

RESULTS

Epidermal MCM6 expression was enhanced in the skin lesions of psoriatic patients. The experiments further revealed that MCM6 was required for the proliferation of keratinocytes and governed by the IL-22/STAT3 pathway. In addition, the antiproliferation effect of benvitimod is achieved by the inhibition of p-JAK1 and p-JAK2, which further restrained the activation of STAT3 in keratinocytes. Lastly, benvitimod could repressed imiquimod-induced skin lesions and the expression of epidermal MCM6 and p-STAT3 in mice. Moreover, knockdown of AHR in keratinocytes enhanced the activation of JAK1 and JAK2.

CONCLUSION

The findings reveal that benvitimod could decrease MCM6-mediated proliferation of keratinocytes by affecting the JAK/STAT3 pathway, thereby serving as a new treatment modality for psoriasis.

A High MCM6 Proliferative Index in Atypical Meningioma Is Associated with Shorter Progression Free and Overall Survivals

The aim of this study was to evaluate the prognostic value of MCM6, in comparison with Ki-67, in two series of grade 1 and 2 meningiomas, and to evaluate its correlation with methylation classes. The first cohort included 100 benign (grade 1, World Health Organization 2021) meningiomas, and the second 69 atypical meningiomas (grade 2). Immunohistochemical Ki-67 and MCM6 labeling indices (LI) were evaluated independently by two observers. Among the atypical meningiomas, 33 cases were also studied by genome-wide DNA methylation. In grade 2 meningiomas, but not grade 1, both Ki-67 and MCM6 LIs were correlated with PFS (p = 0.004 and p = 0.005, respectively; Cox univariate analyses). Additionally, MCM6 was correlated with overall survival only in univariate analysis. In a multivariate model, including mitotic index, Ki-67, MCM6, age, sex, and the quality of surgical resection, only MCM6 was correlated with PFS (p = 0.046). Additionally, we found a significant correlation between PTEN loss and high MCM6 or Ki-67 LIs. Although no correlation was found with the methylation classes and subtypes returned by the meningioma algorithm MNGv2.4., MCM6 LI was significantly correlated with the methylation of 2 MCM6 gene body loci. In conclusion, MCM6 is a relevant prognostic marker in atypical meningiomas. This reproducible and easy-to-use marker allows the identification of a highly aggressive subtype of proliferative meningiomas, characterized notably by frequent PTEN losses, which was previously reported to be sensitive to histone deacetylase inhibitors.

GATA3 positively regulates PAR1 to facilitate in vitro disease progression and decrease cisplatin sensitivity in neuroblastoma via inhibiting the hippo pathway

GATA binding protein 3 (GATA3) is reported to critically involved in the pathogenesis of neuroblastoma (NB). This study investigated the specific role and mechanism of GATA3 in NB progression. JASPAR was utilized to predict GATA3's downstream targets, whose binding relation with GATA3 was inspected by a dual-luciferase reporter assay. NB cell lines underwent transfection of GATA3/protease-activated receptor 1 (PAR1) overexpression plasmids or shGATA3, followed by cisplatin treatment. NB cell sensitivity to cisplatin, viability, migration, invasion, cell cycle progression and apoptosis were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, wound healing assay, transwell assay and flow cytometry, respectively. Expressions of GATA3, PAR1, epithelial-mesenchymal transition-related molecules (N-Cadherin and Vimentin), hippo pathway-related molecules (mammalian Ste20-like kinase (Mst)1, Mst2, Mps one binding (Mob) 1, phosphorylated (p)-Mob1, Yes-associated protein (YAP) and p-YAP) in NB tissues and cell lines were assessed by western blot or qRT-PCR. GATA3 expression was increased in NB tissues and cells. GATA3 overexpression increased NB cell viability, promoted migration, invasion, and cell cycle progression, increased the expressions of N-Cadherin, Vimentin and YAP, decreased the expressions of Mst1, Mst2, Mob1, p-Mob1, p-YAP and the ratio of p-YAP to YAP, and attenuated cisplatin-induce cell apoptosis, which GATA3 knockdown induced the opposite effect. GATA3 directly targeted PAR1, whose overexpression increased NB cell viability, inhibited the hippo pathway, and attenuated cisplatin-induce cell apoptosis, and reversed GATA3 knockdown-induced effect on these aspects. GATA3 positively regulates PAR1 to facilitate in-vitro disease progression and decrease cisplatin sensitivity in NB via inhibiting the hippo pathway.

Comparative proteoinformatics revealed the essentials of SDS impact on HaCaT keratinocytes

There is no direct evidence supporting that SDS is a carcinogen, so to investigate this fact, we used HaCaT keratinocytes as a model of human epidermal cells. To reveal the candidate proteins and/or pathways characterizing the SDS impact on HaCaT, we proposed comparative proteoinformatics pipeline. For protein extraction, the performance of two sample preparation protocols was assessed: 0.2% SDS-based solubilization combined with the 1DE-gel concentration (Protocol 1) and osmotic shock (Protocol 2). As a result, in SDS-exposed HaCaT cells, Protocol 1 revealed 54 differentially expressed proteins (DEPs) involved in the disease of cellular proliferation (DOID:14566), whereas Protocol 2 found 45 DEPs of the same disease ID. The 'skin cancer' term was a single significant COSMIC term for Protocol 1 DEPs, including those involved in double-strand break repair pathway (BIR, GO:0000727). Considerable upregulation of BIR-associated proteins MCM3, MCM6, and MCM7 was detected. The eightfold increase in MCM6 level was verified by reverse transcription qPCR. Thus, Protocol 1 demonstrated high effectiveness in terms of the total number and sensitivity of MS identifications in HaCaT cell line proteomic analysis. The utility of Protocol 1 was confirmed by the revealed upregulation of cancer-associated MCM6 in HaCaT keratinocytes induced by non-toxic concentration of SDS. Data are available via ProteomeXchange with identifier PXD035202.

Diffusible signal factor enhances the saline-alkaline resistance and rhizosphere colonization of Stenotrophomonas rhizophila by coordinating optimal metabolism

Quorum sensing (QS) regulates various physiological processes in a cell density-dependent mode via cell-cell communication. Stenotrophomonas rhizophila DSM14405^T having the diffusible signal factor (DSF)-QS system, is a plant growth-promoting rhizobacteria (PGPR) that enables host plants to tolerate saline-alkaline stress. However, the regulatory mechanism of DSF-QS in S. rhizophila is not fully understood. In this study, we used S. rhizophila DSM14405^T wild-type (WT) and an incompetent DSF production rpfF-knockout mutant to explore the regulatory role of QS in S. rhizophila growth, stress responses, biofilm formation, and colonization under saline-alkaline stress. We found that a lack of DSF-QS reduces the tolerance of S. rhizosphere ΔrpfF to saline-alkaline stress, with a nearly 25-fold reduction in the ΔrpfF population compared with WT at 24 h under stress. Transcriptome analysis revealed that QS helps S. rhizophila WT respond to saline-alkaline stress by enhancing metabolism associated with the cell wall and membrane, oxidative stress response, cell adhesion, secretion systems, efflux pumps, and TonB systems. These metabolic systems enhance penetration defense, Na⁺ efflux, iron uptake, and reactive oxygen species scavenging. Additionally, the absence of DSF-QS causes overexpression of biofilm-associated genes under the regulation of sigma 54 and other transcriptional regulators. However, greater biofilm formation capacity confers no advantage on S. rhizosphere ΔrpfF in rhizosphere colonization. Altogether, our results show the importance of QS in PGPR growth and colonization; QS gives PGPR a collective adaptive advantage in harsh natural environments.