Cancer driver candidate genes AVL9, DENND5A and NUPL1 contribute to MDCK cystogenesis

Heterozygosity-Rich Regions in Canine Genome: Can They Serve as Indicators of Balancing Selection?

Compared to the negative effect of directional selection on genetic diversity, balancing selection acts oppositely and maintains variability across the genome. This study aims to articulate whether balancing selection leads to heterozygosity-rich region islands (HRRIs) forming in the canine genome by investigating 1000 animals belonging to 50 dog breeds via 153,733 autosomal SNPs. A consecutive SNP-based approach was used to identify heterozygosity-rich regions (HRRs). Signals of balancing selection in the genome of studied breeds were then assessed with Tajima's D statistics. A total of 72,062 HRRs with an average length of 324 kb were detected to be unevenly distributed across the genome. A total of 509 and 450 genomic regions were classified as HRRIs and balancing selection signals, respectively. Although the genome-wide distributions of HRRIs varied across breeds, several HRRIs were found in the same locations across multiple breeds. A total of 109 genomic regions were classified as both HRRIs and signals of balancing selection. Even though the genomic coordinates of HRRIs and balancing selection signals did not fully overlap across all genomic regions, balancing selection may play a significant role in maintaining diversity in regions associated with various cancer diseases, immune response, and bone, skin, and cartilage tissue development.

Comprehensive Analysis of Prognostic Alternative Splicing Signatures in Tumor Immune Infiltration in Bladder Cancer

BACKGROUND

Bladder cancer exhibits substantial heterogeneity encompassing genetic expressions and histological features. This heterogeneity is predominantly attributed to alternative splicing (AS) and AS-regulated splicing factors (SFs), which, in turn, influence bladder cancer development, progression, and response to treatment.

OBJECTIVE

This study aimed to explore the immune landscape of aberrant AS in bladder cancer and establish the prognostic signatures for survival prediction.

METHODS

Bladder cancer-related RNA-Seq, transcriptome, and corresponding clinical information were downloaded from The Cancer Genome Atlas (TCGA). Gene set enrichment analysis (GSEA) was used to identify significantly enriched pathways of cancer-related AS events. The underlying interactions among differentially expressed genes (DEGs) and cancer-related AS events were assessed by a protein-protein interaction network. Univariate and multivariate Cox regression analyses were performed to identify crucial prognostic DEGs that co-occurred with cancer-related AS events (DEGAS) for overall survival. The area under the curve (AUC) of receiver operating characteristic (ROC) curves was used to assess the efficiency of the prognostic signatures. The CIBERSORT algorithm was used to explore the abundance of immune infiltrating cells.

RESULTS

A total of 3755 cancer-related AS events and 3110 DEGs in bladder cancer were identified. Among them, 379 DEGs co-occurred with cancer-related AS events (DEGAS), of which 102 DEGAS were associated with 14 dysregulated SFs. GSEA and KEGG analysis showed that cancer-related AS events were predominantly enriched in pathways related to immunity, tumorigenesis, and treatment difficulties of bladder cancer. Multivariate Cox regression analysis identified 8 DEGAS (CABP1, KCNN2, TNFRSF13B, PCDH7, SNRPA1, APOLD1, CX3CL1, and DENND5A) significantly associated with OS, and they were further integrated into the prediction model with good AUCs at 3-year, 5-year and 7-year ROC curves (all>0.7). Immune infiltration analysis revealed the significant enrichment of three immune cell types (B cells naïve, dendritic cells resting, and dendritic cell activated) in high-risk bladder cancer patients.

CONCLUSION

This study not only unveiled comprehensive prognostic signatures of AS events in bladder cancer but also established a robust prognostic model based on survival-related DEGAS. These aberrant AS events, dysregulated SFs, and the identified 8 DEGAS may have significant clinical potential as therapeutic targets for bladder cancer.

BMSCs-derived exosomes carrying miR-668-3p promote progression of osteoblasts in osteonecrosis of the femoral head: Expression of proteins CD63 and CD9

Recently, exosomes that are derived from bone marrow mesenchymal stem cells (BMSCs) have garnered considerable interest due to their significant roles in the processes of bone regeneration and repair. Among the various molecular components present within these exosomes, miR-668-3p has emerged as a pivotal microRNA that may be instrumental in modulating the function and proliferation of osteoblasts, the cells responsible for bone formation. The primary objective of this research was to examine the enhancing effects of BMSC-derived exosomes that are enriched with miR-668-3p on the advancement of osteoblasts in the context of osteonecrosis of the femoral head. Furthermore, the study aimed to analyze how the expression of specific exosomal proteins, namely CD63 and CD9, influences this biological process. To conduct the investigation, BMSCs were isolated from healthy rat models, followed by the extraction of their secreted exosomes. The subsequent phase of the study involved assessing the proliferation and differentiation of osteoblasts by introducing the exosomes enriched with miR-668-3p into an experimental setup representing osteonecrosis of the femoral head. The findings revealed that exosomes derived from BMSCs, which contained miR-668-3p, significantly enhanced the proliferation of osteoblasts as well as the expression of key osteogenic marker genes. Notably, the levels of CD63 and CD9 proteins were markedly increased in the treated groups, indicating that the mechanisms underlying this promotion might involve cell adhesion and the endocytic uptake of exosomes.

Loss of symmetric cell division of apical neural progenitors drives DENND5A-related developmental and epileptic encephalopathy

Developmental and epileptic encephalopathies (DEEs) feature altered brain development, developmental delay and seizures, with seizures exacerbating developmental delay. Here we identify a cohort with biallelic variants in DENND5A, encoding a membrane trafficking protein, and develop animal models with phenotypes like the human syndrome. We demonstrate that DENND5A interacts with Pals1/MUPP1, components of the Crumbs apical polarity complex required for symmetrical division of neural progenitor cells. Human induced pluripotent stem cells lacking DENND5A fail to undergo symmetric cell division with an inherent propensity to differentiate into neurons. These phenotypes result from misalignment of the mitotic spindle in apical neural progenitors. Cells lacking DENND5A orient away from the proliferative apical domain surrounding the ventricles, biasing daughter cells towards a more fate-committed state, ultimately shortening the period of neurogenesis. This study provides a mechanism for DENND5A-related DEE that may be generalizable to other developmental conditions and provides variant-specific clinical information for physicians and families.

Advances in the understanding of nuclear pore complexes in human diseases

BACKGROUND

Nuclear pore complexes (NPCs) are sophisticated and dynamic protein structures that straddle the nuclear envelope and act as gatekeepers for transporting molecules between the nucleus and the cytoplasm. NPCs comprise up to 30 different proteins known as nucleoporins (NUPs). However, a growing body of research has suggested that NPCs play important roles in gene regulation, viral infections, cancer, mitosis, genetic diseases, kidney diseases, immune system diseases, and degenerative neurological and muscular pathologies.

PURPOSE

In this review, we introduce the structure and function of NPCs. Then We described the physiological and pathological effects of each component of NPCs which provide a direction for future clinical applications.

METHODS

The literatures from PubMed have been reviewed for this article.

CONCLUSION

This review summarizes current studies on the implications of NPCs in human physiology and pathology, highlighting the mechanistic underpinnings of NPC-associated diseases.

Variant ranking pipeline for complex familial disorders

Identifying genetic susceptibility factors for complex disorders remains a challenging task. To analyze collections of small and large pedigrees where genetic heterogeneity is likely, but biological commonalities are plausible, we have developed a weights-based pipeline to prioritize variants and genes. The Weights-based vAriant Ranking in Pedigrees (WARP) pipeline prioritizes variants using 5 weights: disease incidence rate, number of cases in a family, genome fraction shared amongst cases in a family, allele frequency and variant deleteriousness. Weights, except for the population allele frequency weight, are normalized between 0 and 1. Weights are combined multiplicatively to produce family-specific-variant weights that are then averaged across all families in which the variant is observed to generate a multifamily weight. Sorting multifamily weights in descending order creates a ranked list of variants and genes for further investigation. WARP was validated using familial melanoma sequence data from the European Genome-phenome Archive. The pipeline identified variation in known germline melanoma genes POT1, MITF and BAP1 in 4 out of 13 families (31%). Analysis of the other 9 families identified several interesting genes, some of which might have a role in melanoma. WARP provides an approach to identify disease predisposing genes in studies with small and large pedigrees.

Loss of symmetric cell division of apical neural progenitors drives DENND5A-related developmental and epileptic encephalopathy

Developmental and epileptic encephalopathies (DEEs) are a heterogenous group of epilepsies in which altered brain development leads to developmental delay and seizures, with the epileptic activity further negatively impacting neurodevelopment. Identifying the underlying cause of DEEs is essential for progress toward precision therapies. Here we describe a group of individuals with biallelic variants in DENND5A and determine that variant type is correlated with disease severity. We demonstrate that DENND5A interacts with MUPP1 and PALS1, components of the Crumbs apical polarity complex, which is required for both neural progenitor cell identity and the ability of these stem cells to divide symmetrically. Induced pluripotent stem cells lacking DENND5A fail to undergo symmetric cell division during neural induction and have an inherent propensity to differentiate into neurons, and transgenic DENND5A mice, with phenotypes like the human syndrome, have an increased number of neurons in the adult subventricular zone. Disruption of symmetric cell division following loss of DENND5A results from misalignment of the mitotic spindle in apical neural progenitors. A subset of DENND5A is localized to centrosomes, which define the spindle poles during mitosis. Cells lacking DENND5A orient away from the proliferative apical domain surrounding the ventricles, biasing daughter cells towards a more fate-committed state and ultimately shortening the period of neurogenesis. This study provides a mechanism behind DENND5A-related DEE that may be generalizable to other developmental conditions and provides variant-specific clinical information for physicians and families.

Circular RNA in Non-small Cell Lung Carcinoma: Identification of Targets and New Treatment Modalities

Despite availability of several treatment options for non-small cell lung cancer (NSCLC), such as surgery, chemotherapy, radiation, targeted therapy and immunotherapy, the survival rate of patients for five years is in the range of 22%. Therefore, identification of new targets and treatment modalities for this disease is an important issue. In this context, we screened the PubMed database for up-regulated circular RNAs (circRNAs) which promote growth of NSCLC in preclinical models in vitro as well as in vivo xenograft models in immuno-compromised mice. This approach led to potential targets for further validation and inhibition with small molecules or antibody-derived entities. In case of preclinical validation, the corresponding circRNAs can be inhibited with small interfering RNAs (siRNA) or short hairpin RNAs (shRNA). The identified circRNAs act by sponging microRNAs (miRs) preventing cleavage of the mRNA of the corresponding targets. We identified nine circRNAs up-regulating transmembrane receptors, five circRNAs increasing expression of secreted proteins, nine circRNAs promoting expression of components of signaling pathways, six circRNAs involved in regulation of splicing and RNA processing, six circRNAs up-regulating actin-related and RNA processing components, seven circRNAs increasing the steady-state levels of transcription factors, two circRNAs increasing high-mobility group proteins, four circRNAs increasing components of the epigenetic modification system and three circRNAs up-regulating protein components of additional systems.

Shared hotspot mutations in oncogenes position dogs as an unparalleled comparative model for precision therapeutics

Naturally occurring canine cancers have remarkable similarities to their human counterparts. To better understand these similarities, we investigated 671 client-owned dogs from 96 breeds with 23 common tumor types, including those whose mutation profile are unknown (anal sac carcinoma and neuroendocrine carcinoma) or understudied (thyroid carcinoma, soft tissue sarcoma and hepatocellular carcinoma). We discovered mutations in 50 well-established oncogenes and tumor suppressors, and compared them to those reported in human cancers. As in human cancer, TP53 is the most commonly mutated gene, detected in 22.5% of canine tumors overall. Canine tumors share mutational hotspots with human tumors in oncogenes including PIK3CA, KRAS, NRAS, BRAF, KIT and EGFR. Hotspot mutations with significant association to tumor type include NRAS G61R and PIK3CA H1047R in hemangiosarcoma, ERBB2 V659E in pulmonary carcinoma, and BRAF V588E (equivalent of V600E in humans) in urothelial carcinoma. Our findings better position canines as a translational model of human cancer to investigate a wide spectrum of targeted therapies.

Identification of stage-specific differentially expressed genes and SNPs in gastric cancer employing RNA-Seq based transcriptome profiling

We analysed over 400 million reads obtained from Illumina sequencing of six pairs of libraries representing two each of stage I, II, and III gastric tumors and corresponding normal tissues to identify differentially expressed genes (DEGs), single nucleotide polymorphisms (SNPs), and transcription factors (TFs). In total, 2207 DEGs including 972 upregulated genes and 1235 downregulated genes were detected. Of these, several stage-specific signature genes were identified. The protein-protein interaction networks involving DEGs and TFs were constructed. The KEGG pathway analysis of SNP harbouring genes revealed their involvement in different cancer related pathways like apoptosis, mTOR pathway, and MAPK signaling pathway. The SNP analysis showed implication of host genes in GO categories like immune system process, regulation of signaling, response to stress, and transport. A biased chromosomal distribution of DEGs and SNP harbouring genes was observed. Our study would provide further insights into the complex regulatory mechanisms operating during gastric tumorigenesis.

Induction of apically mistrafficked epiregulin disrupts epithelial polarity via aberrant EGFR signaling

In polarized MDCK cells, disruption of the tyrosine-based YXXΦ basolateral trafficking motif (Y156A) in the epidermal growth factor receptor (EGFR) ligand epiregulin (EREG), results in its apical mistrafficking and transformation in vivo. However, the mechanisms underlying these dramatic effects are unknown. Using a doxycycline-inducible system in 3D Matrigel cultures, we now show that induction of Y156A EREG in fully formed MDCK cysts results in direct and complete delivery of mutant EREG to the apical cell surface. Within 3 days of induction, ectopic lumens were detected in mutant, but not wild-type, EREG-expressing cysts. Of note, these structures resembled histological features found in subcutaneous xenografts of mutant EREG-expressing MDCK cells. These ectopic lumens formed de novo rather than budding from the central lumen and depended on metalloprotease-mediated cleavage of EREG and subsequent EGFR activity. Moreover, the most frequent EREG mutation in human cancer (R147stop) resulted in its apical mistrafficking in engineered MDCK cells. Thus, induction of EREG apical mistrafficking is sufficient to disrupt selective aspects of polarity of a preformed polarized epithelium. This article has an associated First Person interview with the first author of the paper.

Canine tumor mutational burden is correlated with TP53 mutation across tumor types and breeds

Spontaneous canine cancers are valuable but relatively understudied and underutilized models. To enhance their usage, we reanalyze whole exome and genome sequencing data published for 684 cases of >7 common tumor types and >35 breeds, with rigorous quality control and breed validation. Our results indicate that canine tumor alteration landscape is tumor type-dependent, but likely breed-independent. Each tumor type harbors major pathway alterations also found in its human counterpart (e.g., PI3K in mammary tumor and p53 in osteosarcoma). Mammary tumor and glioma have lower tumor mutational burden (TMB) (median < 0.5 mutations per Mb), whereas oral melanoma, osteosarcoma and hemangiosarcoma have higher TMB (median ≥ 1 mutations per Mb). Across tumor types and breeds, TMB is associated with mutation of TP53 but not PIK3CA, the most mutated genes. Golden Retrievers harbor a TMB-associated and osteosarcoma-enriched mutation signature. Here, we provide a snapshot of canine mutations across major tumor types and breeds.

Exome hits demystified: The next frontier

Severe mental illnesses such as schizophrenia and bipolar disorder have complex inheritance patterns, involving both common and rare variants. Whole exome sequencing is a promising approach to find out the rare genetic variants. We had previously reported several rare variants in multiplex families with severe mental illnesses. The current article tries to summarise the biological processes and pattern of expression of genes harbouring the aforementioned variants, linking them to known clinical manifestations through a methodical narrative review. Of the 28 genes considered for this review from 7 families with multiple affected individuals, 6 genes are implicated in various neuropsychiatric manifestations including some variations in the brain morphology assessed by magnetic resonance imaging. Another 15 genes, though associated with neuropsychiatric manifestations, did not have established brain morphological changes whereas the remaining 7 genes did not have any previously recorded neuropsychiatric manifestations at all. Wnt/b-catenin signaling pathway was associated with 6 of these genes and PI3K/AKT, calcium signaling, ERK, RhoA and notch signaling pathways had at least 2 gene associations. We present a comprehensive review of biological and clinical knowledge about the genes previously reported in multiplex families with severe mental illness. A 'disease in dish approach' can be helpful to further explore the fundamental mechanisms.

hsa_circ_0058357 acts as a ceRNA to promote non‑small cell lung cancer progression via the hsa‑miR‑24‑3p/AVL9 axis

Abnormal circular RNAs (circRNAs) are associated with biological processes in cancer; however, the function of circRNAs remains largely unknown in non-small cell lung cancer (NSCLC). The present study aimed to investigate the role of hsa_circ_0058357 on the progression of NSCLC. Cell proliferation, migration and apoptosis were determined using Cell Counting Kit-8, Transwell and flow cytometry assays, respectively. Gene [circRNA and microRNA (miR)] and protein expression levels were determined via reverse transcription-quantitative PCR and immunoblotting. A luciferase assay was employed to detect the binding of miR-24-3p with AVL9 cell migration associated (AVL9), while a cancer xenograft model was established to evaluate cancer growth in vivo. The results demonstrated that hsa_circ_0058357 was highly expressed in human NSCLC tissues and NSCLC cells compared with para-cancerous tissues and human bronchial epithelial (HBE) cells, respectively. Knockdown of hsa_circ_0058357 significantly suppressed cell viability, migration and tumor growth, while it promoted apoptosis in NSCLC cells. As a competing endogenous RNA, hsa_circ_0058357 knockdown contributed to the increase of miR-24-3p expression in NSCLC cells. Of note, overexpression of miR-24-3p markedly abolished the exogenous hsa_circ_0058357-induced excessive proliferation, migration and apoptosis resistance of NSCLC cells. Mechanistically, as a signaling molecule in late secretory pathway, AVL9 was also expressed at a high level in NSCLC tissues and cells, which could be directly suppressed by miR-24-3p. In the tumor tissues, along with growth inhibition, hsa_circ_0058357 knockdown also mediated the elevation of miR-24-3p and the reduction of AVL9. Thus, it was suggested that hsa_circ_0058357 may be a crucial regulation factor in NSCLC by sponging hsa-miR-24-3p, leading to a decrease in miR-24-3p expression, and subsequent increase in AVL9 expression. Therefore, hsa_circ_0058357 may serve as a potential target for diagnosis and gene therapy for NSCLC.

The lncRNA ALMS1-IT1 may promote malignant progression of lung adenocarcinoma via AVL9-mediated activation of the cyclin-dependent kinase pathway

Lung adenocarcinoma (LUAD) is the primary epithelial tumor of the lung. The lack of clinical symptoms and specific molecular diagnostic indicators during the early stages of LUAD mean that the disease may not be detected until late stages, and the 5‐year survival rate is only approximately 15%. Long non‐coding RNA ALMS1 intronic script 1 (ALMS1‐IT1) was previously reported to be correlated with the poor prognosis of head and neck squamous cell carcinoma patients. Here, we investigated whether ALMS1‐IT1 has prognostic potential for LUAD. Bioinformatics analyses were performed to examine the expression and prognostic value of ALMS1 and AVL9 (for which gene expression is positively correlated with ALMS1‐IT1 expression in LUAD) in LUAD based on TCGA and Oncomine databases. We report that ALMS1‐IT1 and AVL9 were both highly expressed in LUAD and correlated with poor outcomes in LUAD patients. Of note, the prognosis of LUAD patients with low expression of both ALMS1‐IT1 and AVL9 was superior to that of other patients. Furthermore, the proliferation, migration and invasion of LUAD cells were decreased in cells lacking ALMS1‐IT1, and this decrease could be almost completely reversed through overexpression of AVL9. Gene set enrichment analysis revealed that expression of genes related to the cell cycle pathway is closely related to both the high expression of ALMS1‐IT1 and AVL9 in LUAD. Finally, up‐regulation of ALMS1‐IT1 can activate the cyclin‐dependent kinase pathway, whereas absence of AVL9 can reverse this activation, as shown by western blotting. In summary, ALMS1‐IT1/AVL9 may promote the malignant progression of LUAD, at least in part by regulating the cyclin‐dependent kinase pathway.

Biomarker potentials of miRNA-associated circRNAs in breast cancer (MCF-7) cells: an in vitro and in silico study

Breast cancer is a heterogeneous disease, which is the most common malignancy in women. The incidence and mortality rates of breast cancer indicate that it is the leading cause of cancer-related with deaths. circRNAs operate as part of competing endogenous RNAs (ceRNAs) mechanisms, which play critical roles in the different biological processes of breast cancer such as proliferation, migration, and apoptosis. The goal of the present study is to identify the potential predictive biomarker for breast cancer diagnosis in the circRNA network by in vitro and in silico analyzes. 40 miRNAs were obtained from the miRWalk database and their combinatorial target genes (potential ceRNAs) were identified with ComiR. We stated that the cancer-specific circRNA genes in MCF-7 cells using the cancer-specific circRNA (CSDC) database, and obtained the ones showing potential ceRNA activity in our previous analysis among them. Identified genes with remarkable expression differences between BCa and normal breast tissue were determined by the GEPIA database. Moreover, the Spearman correlation test in the GEPIA database was used for the statistical analysis of the relationship between DCAF7 and SOGA1, SOGA1 and AVL 9, DCAF7 and AVL 9 gene pairs. And also, DCAF7, SOGA1, and AVL9 gene expression levels were detected in MCF-7 and MCF-10A cells by RT-qPCR method. DCAF7, SOGA1, and AVL9 gene were significantly more expressed to BCa tissue and MCF-7 cells than normal breast tissue and MCF-10 A cells. And also, DCAF7 and SOGA1, SOGA1 and AVL9, DCAF7 and AVL9 genes pairs were found to be significantly correlated with BCa. These genes may be considered as potential predictive biomarkers to discriminate BCa patients from healthy persons. Our preliminary results can supply a new perspective for in vitro and vivo studies in the future.

AVL9 is Upregulated in and Could Be a Predictive Biomarker for Colorectal Cancer

PURPOSE

This study aimed to explore the function and clinical significance of AVL9 in colorectal cancer (CRC).

MATERIALS AND METHODS

The GEO, TCGA, and GEPIA databases were searched to evaluate the expression level of AVL9, while the SurvExpress online tool was used to explore its related clinical survival prognosis. The cBioPortal and LinkedOmics databases were used to identify AVL9 expression-related genes. Protein-protein interaction (PPI) networks were analyzed using Cytoscape 3.7.1 and DAVID6.8, which was used to perform Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genome (KEGG) signal pathway enrichment. The immunohistochemistry of AVL9 in CRC was detected using an online tool protein atlas. RNA isolation and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assays were used to detect AVL9 expression in tissue and plasma samples.

RESULTS

Our study confirmed that AVL9 was highly expressed in CRC lesions versus the adjacent normal tissues (P < 0.001). High AVL9 expression was negatively associated with survival outcomes (P < 0.05). GO analysis showed that AVL9 expression-related genes were enriched in single organismal cell-cell adhesion, post-transcriptional regulation of gene expression, and negative regulation of the vascular endothelial growth factor receptor signaling pathway (P < 0.05). On a KEGG pathway analysis, these genes were mainly involved in progesterone-mediated oocyte maturation, axon guidance, the insulin signaling pathway, and the ubiquitin-mediated proteolysis signaling pathways (P < 0.05). In the PPI analysis, the KBTBD2, KIAA1147, EPDR1, and RNF216 genes interacted with AVL9, and GEPIA predicted that their expression levels were all positively correlated with AVL9. Furthermore, a clinicopathological parameter analysis found that high AVL9 expression was positively correlated with differentiation and TNM stage. RT-qPCR analysis further showed that plasma AVL9 expression was upregulated in CRC patients versus healthy controls.

CONCLUSION

AVL9 could serve as a potential biomarker and therapeutic target for CRC.

A Qualitative Change in the Transcriptome Occurs after the First Cell Cycle and Coincides with Lumen Establishment during MDCKII Cystogenesis

Madin-Darby canine kidney II (MDCKII) cells are widely used to study epithelial morphogenesis. To better understand this process, we performed time course RNA-seq analysis of MDCKII 3D cystogenesis, along with polarized 2D cells for comparison. Our study reveals a biphasic change in the transcriptome that occurs after the first cell cycle and coincides with lumen establishment. This change appears to be linked to translocation of β-catenin, supported by analyses with AVL9- and DENND5A-knockdown clones, and regulation by HNF1B, supported by ATAC-seq study. These findings indicate a qualitative change model for transcriptome remodeling during epithelial morphogenesis, leading to cell proliferation decrease and cell polarity establishment. Furthermore, our study reveals that active mitochondria are retained and chromatin accessibility decreases in 3D cysts but not in 2D polarized cells. This indicates that 3D culture is a better model than 2D culture for studying epithelial morphogenesis.

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The transcriptome switches after the first cell cycle and during MDCKII lumenogenesis

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The transcriptome switch is linked to β-catenin translocation and HNF1B activation

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Chromatin accessibility decreases during MDCKII cystogenesis

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Active mitochondria are maintained in 3D, but not 2D, epithelial morphogenesis

Clinical significance and functions of miR-203a-3p/AVL9 axis in human non-small-cell lung cancer

Aim: We aimed to investigate the clinical significance and biological function of miR-203a-3p in non-small-cell lung cancer (NSCLC). Methods: The association between miR-203a-3p expression and clinicopathological parameters in NSCLC was assessed by χ² test. Kaplan-Meier method and Cox regression model were applied to evaluate the prognosis value of miR-203a-3p. The biological function of miR-203-3p was explored using CCK-8 and transwell assays. Results: Significantly downregulated miR-203a-3p was associated with TNM stage, lymph node metastasis and poor prognosis. AVL9 was identified as a direct target of miR-203a-3p. Functionally, we found overexpression of miR-203a-3p inhibited cell proliferation, migration and invasion in NSCLC cells by targeting AVL9. Conclusion: Collectively, targeting the miR-203a-3p/AVL9 axis might help to develop useful therapeutic target for NSCLC.

Mutations in PLS1, encoding fimbrin, cause autosomal dominant nonsyndromic hearing loss

Nonsyndromic hearing loss (NSHL), a common sensory disorder, is characterized by high clinical and genetic heterogeneity (i.e., approximately 115 genes and 170 loci so far identified). Nevertheless, almost half of patients submitted for genetic testing fail to receive a conclusive molecular diagnosis. We used next-generation sequencing to identify causal variants in PLS1 (c.805G>A, p.[E269K]; c.713G>T, p.[L238R], and c.383T>C, p.[F128S]) in three unrelated families of European ancestry with autosomal dominant NSHL. PLS1 encodes Plastin 1 (also called fimbrin), one of the most abundant actin-bundling proteins of the stereocilia. In silico protein modeling suggests that all variants destabilize the structure of the actin-binding domain 1, likely reducing the protein's ability to bind F actin. The role of PLS1 gene in hearing function is further supported by the recent demonstration that Pls1^{-/ -} mice show a hearing loss phenotype similar to that of our patients. In summary, we report PLS1 as a novel gene for autosomal dominant NSHL, suggesting that this gene is required for normal hearing in humans and mice.

A Humanized Yeast Phenomic Model of Deoxycytidine Kinase to Predict Genetic Buffering of Nucleoside Analog Cytotoxicity

Knowledge about synthetic lethality can be applied to enhance the efficacy of anticancer therapies in individual patients harboring genetic alterations in their cancer that specifically render it vulnerable. We investigated the potential for high-resolution phenomic analysis in yeast to predict such genetic vulnerabilities by systematic, comprehensive, and quantitative assessment of drug–gene interaction for gemcitabine and cytarabine, substrates of deoxycytidine kinase that have similar molecular structures yet distinct antitumor efficacy. Human deoxycytidine kinase (dCK) was conditionally expressed in the Saccharomyces cerevisiae genomic library of knockout and knockdown (YKO/KD) strains, to globally and quantitatively characterize differential drug–gene interaction for gemcitabine and cytarabine. Pathway enrichment analysis revealed that autophagy, histone modification, chromatin remodeling, and apoptosis-related processes influence gemcitabine specifically, while drug–gene interaction specific to cytarabine was less enriched in gene ontology. Processes having influence over both drugs were DNA repair and integrity checkpoints and vesicle transport and fusion. Non-gene ontology (GO)-enriched genes were also informative. Yeast phenomic and cancer cell line pharmacogenomics data were integrated to identify yeast–human homologs with correlated differential gene expression and drug efficacy, thus providing a unique resource to predict whether differential gene expression observed in cancer genetic profiles are causal in tumor-specific responses to cytotoxic agents.

Nucleoporin Nup58 localizes to centrosomes and mid-bodies during mitosis

Background

Nuclear pore complexes (NPCs) act as nano-turnstiles within nuclear membranes between the cytoplasm and nucleus of mammalian cells. NPC proteins, called nucleoporins (Nups), mediate trafficking of proteins and RNA into and out of the nucleus, and are involved in a variety of mitotic processes. We previously reported that Nup62 localizes to the centrosome and mitotic spindle during mitosis, and plays a role in centrosome homeostasis. However, whether Nup58, a Nup62 subcomplex protein, also localizes to spindle poles is unknown.

Result

Herein, we show that Nup58 localizes to the nuclear rim during interphase, and to mitotic spindles, centrosomes, and midbodies during mitosis. Our confocal microscopy, live-cell imaging, and stimulated emission depletion nanoscopy results also demonstrated that Nup58 localized to the centrosomes during metaphase and relocalized to midbodies during abscission. Depletion of Nup58 resulted in centrosomal abnormalities and delayed abscission.

Conclusion

Nup58 localized at the centrosomes and mitotic spindle during metaphase and relocalized at midbodies during abscission. This study highlights the important role of Nup58 in mitosis.

NUP58 facilitates metastasis and epithelial-mesenchymal transition of lung adenocarcinoma via the GSK-3β/Snail signaling pathway

The NUP58 gene encodes a nucleus-pore protein that is a component of nuclear pore complex (NPC). NPC facilitates the transportation of macromolecules (ions and other substances) into the nuclei of eukaryotic cells. However, there are no relevant reports about the NUP58 gene in human lung cancer. In this study, we demonstrated that NUP58 was highly expressed in the primary and metastatic foci of lung adenocarcinoma, with low expression in adjacent tissues and normal lung tissue. In patients with lung adenocarcinoma, the NUP58 gene was highly expressed in patients with stage IV disease (P < 0.05); NUP58 knockdown using a lentiviral vector-mediated shRNA inhibited metastasis and invasion of lung adenocarcinoma cell lines A549 and H1299 in vivo and in vitro. Furthermore, silencing of NUP58 resulted in altered expression of EMT markers, associated GSK-3β/Snail pathways, tumor metastasis and invasion factors. In conclusion, these findings demonstrated that NUP58 can promote the metastasis and invasion of lung adenocarcinoma, which can be partially attributed to the GSK-3β/Snail signaling pathway.

Linc00662 Promotes Tumorigenesis and Progression by Regulating miR-497-5p/AVL9 Axis in Colorectal Cancer

BACKGROUND

Recently, multiple lines of evidence have demonstrated that linc00662 serves as an oncogene in various cancers. However, the exact mechanism of oncogenesis mediated by linc00662 in colorectal cancer (CRC) remains unknown. In this study, we aimed to explore the biological role of linc00662 in the regulation of CRC progression.

METHODS

Both gene expression omnibus (GEO) and the cancer genome atlas (TCGA) datasets were used to evaluate the expression of linc00662. RT-qPCR was used to analyze the expression of linc00662, miR-497-5p, and AVL9 in CRC clinical samples and cell lines. Cell Counting Kit-8 (CCK-8), flow cytometry, transwell assay, and xenograft model were used to investigate the effect of linc00662 on CRC cell proliferation, cell cycle, and metastasis. Western blot analysis was used to analyze the expression of the epithelial-mesenchymal transition (EMT)-associated markers. Furthermore, bioinformatics analysis and mechanism assays were used to elucidate the underlying mechanism. Dual-luciferase reporter assays were used to analyze the regulatory relationships among linc00662, miR-497-5p, and AVL9.

RESULTS

In this study, we found that the expression of linc00662 was significantly upregulated in CRC tissues compared to normal tissues and positively correlated with tissue differentiation, T stage, and lymphatic metastasis. Further, our data showed that the expression of linc00662 was positively associated with lymph node metastasis, TMN stage, and poor-moderate differentiation. Patients with higher linc00662 expression level were more likely to have poorer overall survival. Knockdown of linc00662 inhibited CRC cell growth, induced cell apoptosis, triggered cell cycle arrest at G2/M phase, and suppressed cell migration and invasion through regulating the EMT pathway. Further, mechanistic studies revealed that knockdown of linc00662 significantly reduced the expression of AVL9, a direct target of miR-497-5p.

CONCLUSIONS

Linc00662 was significantly upregulated in CRC, and mediated CRC progression and metastasis by competing with miR-497-5p to modulate the expression of AVL9. Therefore, our result sheds light on the potential application of linc00662 in CRC diagnosis and therapy.

Proliferative and Invasive Colorectal Tumors in Pet Dogs Provide Unique Insights into Human Colorectal Cancer

Spontaneous tumors in pet dogs represent a valuable but undercharacterized cancer model. To better use this resource, we performed an initial global comparison between proliferative and invasive colorectal tumors from 20 canine cases, and evaluated their molecular homology to human colorectal cancer (CRC). First, proliferative canine tumors harbor overactivated WNT/β-catenin pathways and recurrent CTNNB1 (β-catenin) mutations S45F/P, D32Y and G34E. Invasive canine tumors harbor prominent fibroblast proliferation and overactivated stroma. Both groups have recurrent TP53 mutations. We observed three invasion patterns in canine tumors: collective, crypt-like and epithelial–mesenchymal transition (EMT). We detected enriched Helicobacter bilis and Alistipes finegoldii in proliferative and crypt-like tumors, but depleted mucosa-microbes in the EMT tumor. Second, guided by our canine findings, we classified 79% of 478 human colon cancers from The Cancer Genome Atlas into four subtypes: primarily proliferative, or with collective, crypt-like or EMT invasion features. Their molecular characteristics match those of canine tumors. We showed that consensus molecular subtype 4 (mesenchymal) of human CRC should be further divided into EMT and crypt-like subtypes, which differ in TGF-β activation and mucosa-microbe content. Our canine tumors share the same pathogenic pathway as human CRCs. Dog-human integration identifies three CRC invasion patterns and improves CRC subtyping.

SEG - A Software Program for Finding Somatic Copy Number Alterations in Whole Genome Sequencing Data of Cancer

As next-generation sequencing technology advances and the cost decreases, whole genome sequencing (WGS) has become the preferred platform for the identification of somatic copy number alteration (CNA) events in cancer genomes. To more effectively decipher these massive sequencing data, we developed a software program named SEG, shortened from the word “segment”. SEG utilizes mapped read or fragment density for CNA discovery. To reduce CNA artifacts arisen from sequencing and mapping biases, SEG first normalizes the data by taking the log₂-ratio of each tumor density against its matching normal density. SEG then uses dynamic programming to find change-points among a contiguous log₂-ratio data series along a chromosome, dividing the chromosome into different segments. SEG finally identifies those segments having CNA. Our analyses with both simulated and real sequencing data indicate that SEG finds more small CNAs than other published software tools.

Hypoxia-regulated lncRNA CRPAT4 promotes cell migration via regulating AVL9 in clear cell renal cell carcinomas

Introduction

Long noncoding RNAs (lncRNAs) are proven to be key regulators in cancer biology. Our screening effort for clear cell renal cell carcinoma (ccRCC) prognosis-associated lncRNAs identified a novel lncRNA, ccRCC prognosis-associated transcript 4 (CRPAT4), as one of the top candidates that was previously uncharacterized. The aim of this study was to verify the clinical significance of CRPAT4 in ccRCC patients and to explore its biological role as well as the underlying mechanisms, in ccRCC cell lines.

Materials and methods

Quantitative real-time polymerase chain reaction (PCR) was performed to demonstrate that CRPAT4 was differentially expressed between ccRCC and the normal controls and that high CRPAT4 expression significantly associated with advanced Fuhrman nuclear grades.

Results

Kaplan–Meier survival analysis with The Cancer Genome Atlas KIRC RNA sequencing data indicated that high CRPAT4 expression was significantly associated with poor overall survival and progression-free survival. Functional studies indicated that CRPAT4 was an HIF-1α regulated gene, and CRPAT4 knockdown significantly inhibited cell migration and proliferation in the absence of HIF-1α. In addition, a mechanistic study revealed that CRPAT4 could regulate the expression of the migration-associated protein AVL9.

Conclusion

Collectively, our study first identified CRPAT4 as a hypoxia-regulated lncRNA, acting as an oncogene in ccRCC progression via regulating AVL9 protein, thus expanding our knowledge on the hypoxia pathway in ccRCC biology from a noncoding perspective. Moreover, CRPAT4 has the potential to be a prognostic marker in ccRCC patients.

Collaborating genomic, transcriptomic and microbiomic alterations lead to canine extreme intestinal polyposis

Extreme intestinal polyposis in pet dogs has not yet been reported in literature. We identified a dog patient who developed numerous intestinal polyps, with the severity resembling human classic familial adenomatous polyposis (FAP), except the jejunum-ileum junction being the most polyp-dense. We investigated this dog, in comparison with 22 other dogs with spontaneous intestinal tumors but no severe polyposis, and with numerous published human cancers. We found, not APC mutation, but three other alteration pathways as likely reasons of this canine extreme polyposis. First, somatic truncation mutation W411X of FBXW7, a component of an E3 ubiquitin ligase, over-activates MYC and cell cycle-promoting network, accelerating crypt cell proliferation. Second, genes of protein trafficking and localization are downregulated, likely associated with germline mutation G406D of STAMBPL1, a K63-deubiquitinase, and MYC network activation. This inhibits epithelial apical-basolateral polarity establishment, preventing crypt cell differentiation. Third, Bacteroides uniformis, a commensal gut anaerobe, thrives and expresses abundantly thioredoxin and nitroreductase. These bacterial products could reduce oxidative stress linked to host germline mutation R51X of CYB5RL, a cytochrome b5 reductase homologue, decreasing cell death. Our work emphasizes the close collaboration of alterations across the genome, transcriptome and microbiome in promoting tumorigenesis.

Circular RNA circ-4099 is induced by TNF-α and regulates ECM synthesis by blocking miR-616-5p inhibition of Sox9 in intervertebral disc degeneration

Circular RNAs (circRNAs) play important roles in the initiation and development of different diseases. Here, we detected their role in intervertebral disc (IVD) degeneration. An Arraystar human circular RNA microarray assay was used to detect circRNAs in normal and degenerated human IVD nucleus pulposus (NP) tissues. The role of circ-4099 in IVDD and its mechanism were evaluated by qRT-PCR and gain-of-function/loss-of-function studies. Interaction networks for competing endogenous RNAs (ceRNAs), miRNAs, and miRNA target gene were detected by bioinformatics analysis, RNA immunoprecipitation and luciferase assay. Expression of seventy-two circRNAs were increased by more than twofold in degenerated NP tissues. qRT-PCR showed that the expression of circ-4099 in NP tissues was consistent with that of the array screening. Over-expression of circ-4099 increased the expression of Collagen II and Aggrecan and decreased the secretion of the pro-inflammatory factors IL-1β, TNF-α, and PGE2. TNF-α treatment increased circ-4099 expression in NP cells. NF-κB/MAPK inhibitors or shRNAs abolished the inductive effects of TNF-α on circ-4099 expression. We further demonstrated that circ-4099 was able to function as a “sponge” by competitively binding miR-616-5p, which reversed the suppression of Sox9 by miR-616-5p. We used DNA pull-down and spectrometry experiments to show that TNF-α can promote circ-4099 transcription through upregulation of GRP78. We provide the first evidence that shows circRNAs are differentially expressed in degenerated and normal NP tissues. Circ-4099 may play a role in a protective mechanism and be part of a compensatory response that maintains the synthesis and secretion of the extracellular matrix in NP cells and might be a protective factor in IVD degeneration as well as restore NP cell function.

A circular RNA molecule helps protect against degenerative disc disease. Hua Wang and coworkers from Sun Yat-Sen University in Guangzhou, China, examined whether circular RNAs, regulatory molecules that take the form of closed RNA loops, contribute to intervertebral disc degeneration, a condition in which connective tissue in the spine breaks down over time, causing back pain and weakness. They found 72 circular RNAs that were either significantly over- or under-expressed in the inner core tissue of intervertebral discs from patients with this condition. They showed that one of these circular RNAs, circ-4099, increased the production of key cartilage proteins. This RNA also blocked the activity of another non-circular regulatory RNA that normally inhibits a molecular pathway needed for proper cartilage formation. Enhancing the activity of this protective molecule could help treat degenerative disc disease.

MYCN promotes neuroblastoma malignancy by establishing a regulatory circuit with transcription factor AP4

Amplification of the MYCN oncogene, a member of the MYC family of transcriptional regulators, is one of the most powerful prognostic markers identified for poor outcome in neuroblastoma, the most common extracranial solid cancer in childhood. While MYCN has been established as a key driver of malignancy in neuroblastoma, the underlying molecular mechanisms are poorly understood. Transcription factor activating enhancer binding protein-4 (TFAP4) has been reported to be a direct transcriptional target of MYC. We show for the first time that high expression of TFAP4 in primary neuroblastoma patients is associated with poor clinical outcome. siRNA-mediated suppression of TFAP4 in MYCN-expressing neuroblastoma cells led to inhibition of cell proliferation and migration. Chromatin immunoprecipitation assay demonstrated that TFAP4 expression is positively regulated by MYCN. Microarray analysis identified genes regulated by both MYCN and TFAP4 in neuroblastoma cells, including Phosphoribosyl-pyrophosphate synthetase-2 (PRPS2) and Syndecan-1 (SDC1), which are involved in cancer cell proliferation and metastasis. Overall this study suggests a regulatory circuit in which MYCN by elevating TFAP4 expression, cooperates with it to control a specific set of genes involved in tumor progression. These findings highlight the existence of a MYCN-TFAP4 axis in MYCN-driven neuroblastoma as well as identifying potential therapeutic targets for aggressive forms of this disease.

Canine spontaneous head and neck squamous cell carcinomas represent their human counterparts at the molecular level

Spontaneous canine head and neck squamous cell carcinoma (HNSCC) represents an excellent model of human HNSCC but is greatly understudied. To better understand and utilize this valuable resource, we performed a pilot study that represents its first genome-wide characterization by investigating 12 canine HNSCC cases, of which 9 are oral, via high density array comparative genomic hybridization and RNA-seq. The analyses reveal that these canine cancers recapitulate many molecular features of human HNSCC. These include analogous genomic copy number abnormality landscapes and sequence mutation patterns, recurrent alteration of known HNSCC genes and pathways (e.g., cell cycle, PI3K/AKT signaling), and comparably extensive heterogeneity. Amplification or overexpression of protein kinase genes, matrix metalloproteinase genes, and epithelial-mesenchymal transition genes TWIST1 and SNAI1 are also prominent in these canine tumors. This pilot study, along with a rapidly growing body of literature on canine cancer, reemphasizes the potential value of spontaneous canine cancers in HNSCC basic and translational research.