A novel nuclear complex of DRR1, F-actin and COMMD1 involved in NF-κB degradation and cell growth suppression in neuroblastoma

FAM107A as a tumor suppressor in esophageal squamous carcinoma inhibits growth and metastasis

BACKGROUND

Sequence similarity Family 107 member A (FAM107A) has been recognized as a tumor suppressor of various malignancies, which suppresses tumor proliferation and metastasis. Its specific role in esophageal squamous cell carcinoma (ESCC) remains unclear.

METHODS

Public datasets including Gene Expression Profiling Interactive Analysis (GEPIA) and Gene Expression Omnibus (GEO), quantitative real-time PCR (qRT-PCR), and Western blot were utilized for comparative analysis of FAM107A expression between ESCC and normal tissues. The link between FAM107A and clinicopathological features, as well as prognosis determined through χ2-test, log-rank analysis, and univariate and multivariate analyses, respectively. The impact of FAM107A on ESCC cell malignant behavior was confirmed through in vitro assays, including cell counting using the Cell Counting Kit-8 (CCK-8), clonal formation, wound healing, and transwell assays. Western blot analysis was employed to assess the effects of FAM107A on tumor epithelial-mesenchymal transition (EMT) and cell cycle-related proteins. Finally, xenograft tumors were developed to investigate the influence of FAM107A on ESCC growth in vivo.

RESULTS

FAM107A exhibited low expression in ESCC tissues. Reduced FAM107A expression was associated with a poorer prognosis and unfavorable clinicopathological characteristics, such as degree of differentiation, T-stage, and N-stage. Overexpression of FAM107A suppressed ESCC cell proliferation, invasion, migration, the EMT process, and cell cycle progression. Finally, FAM107A overexpression inhibited tumor development in vivo.

CONCLUSION

The decreased expression of FAM107A is indicative of a worse prognosis for ESCC patients. FAM107A exerts inhibitory impacts on malignant behavior and may hold promise as a therapeutic target for ESCC.

DRR1 promotes neuroblastoma cell differentiation by regulating CREB expression

BACKGROUND

Neuroblastoma is the most common cancer in infants and the most common extracranial solid tumor in childhood. DRR1 was identified to be downregulated in poorly differentiated ganglion cells from neuroblastoma model mice. However, the roles of DRR1 in neuroblastoma remain largely unclear.

METHODS

The neuroblastoma cells were induced to differentiate, and the expression of DRR1 was detected. The expression of the neuroblastoma cell differentiation markers was analyzed in DRR1 shRNA- or DRR1-expressing vector-treated neuroblastoma cells. The downstream genes of DRR1 were screened with ChIP-seq assay. Finally, TNB1 cells were infected with DRR1 shRNA and CREB expressing vector containing lentivirus, and the expression of the cell differentiation markers, cell cycle distribution and tumor growth were analyzed.

RESULTS

The expression of DRR1 was increased in differentiated neuroblastoma cells, and downregulation of DRR1 expression inhibited the differentiation of neuroblastoma cells. Further experiments indicated that CREB is a candidate downstream gene of DRR1, and it mediates neuroblastoma cell differentiation. Moreover, overexpression of CREB rescued the effect of DRR1 shRNA on cell differentiation, cell cycle distribution and tumor growth in neuroblastoma.

CONCLUSIONS

DRR1-CREB axis modulates the differentiation of neuroblastoma cells and is associated with the outcome of neuroblastoma patients.

IMPACT

DRR1 is involved in regulation of the differentiation of neuroblastoma. Binding with actin is essential for DRR1 to regulate neuroblastoma cell differentiation. CREB is a candidate downstream gene of DRR1 in regulating of the differentiation of neuroblastoma.

COMMD proteins function and their regulating roles in tumors

The COMMD proteins are a highly conserved protein family with ten members that play a crucial role in a variety of biological activities, including copper metabolism, endosomal sorting, ion transport, and other processes. Recent research have demonstrated that the COMMD proteins are closely associated with a wide range of disorders, such as hepatitis, myocardial ischemia, cerebral ischemia, HIV infection, and cancer. Among these, the role of COMMD proteins in tumors has been thoroughly explored; they promote or inhibit cancers such as lung cancer, liver cancer, gastric cancer, and prostate cancer. COMMD proteins can influence tumor proliferation, invasion, metastasis, and tumor angiogenesis, which are strongly related to the prognosis of tumors and are possible therapeutic targets for treating tumors. In terms of molecular mechanism, COMMD proteins in tumor cells regulate the oncogenes of NF-κB, HIF, c-MYC, and others, and are related to signaling pathways including apoptosis, autophagy, and ferroptosis. For the clinical diagnosis and therapy of malignancies, additional research into the involvement of COMMD proteins in cancer is beneficial.

Multi-omics analysis of the oncogenic value of copper Metabolism-Related protein COMMD2 in human cancers

BACKGROUND

The copper metabolism MURR1 domain (COMMD) protein family is involved in tumorigenicity of malignant tumors. However, as the member of COMMD, the role of COMMD2 in human tumors remains unknown.

METHODS

We used The Cancer Genome Atlas (TCGA), Genotype Tissue Expression (GTEx), Human Protein Atlas (HPA) database, Cancer Cell Line Encyclopedia (CCLE) platform, univariate Cox regression analysis, Kaplan-Meier curve, cBioPortal, UALCAN database, Sangerbox online platform, GSCA database gene set enrichment analysis (GSEA), and GeneMANIA to analyze the expression of COMMD2, its prognostic values, genomic alteration patterns, and the correlation with tumor stemness, tumor mutational burden (TMB), microsatellite instability (MSI), and immune infiltrates, drug sensitivity, and gene function enrichment in pan-cancer. qRT-PCR, CCK-8, EdU, wound healing, and transwell migration assays were performed to confirm the function of COMMD2.

RESULTS

COMMD2 was strongly expressed in most cancer types. Elevated COMMD2 expression affects the prognosis, clinicopathological stage, and molecular or immune subtypes of various tumors. Moreover, promoter hypomethylation and mutations in the COMMD2 gene may be associated with its high expression and poor survival. Additionally, we discovered that COMMD2 expression was linked to tumor stemness, TMB, MSI, immune cell infiltration, immune-checkpoint inhibitors, and drug sensitivity in pan-cancer. Furthermore, the COMMD2 gene co-expression network is constructed with GSEA analysis, displaying significant interaction of COMMD2 with E2F targets, G2-M checkpoint, and mitotic spindle in bladder cancer (BLCA). Finally, RNA interference data showed suppression of COMMD2 prevented proliferation and migration of BLCA and uterine corpus endometrial carcinoma (UCEC) cells.

CONCLUSION

Our findings shed light on the COMMD2 functions in human cancers and demonstrate that it is a promising prognostic biomarker and therapeutic target in pan-cancer.

FAM107A Inactivation Associated with Promoter Methylation Affects Prostate Cancer Progression through the FAK/PI3K/AKT Pathway

Simple Summary

Prostate cancer (PCa) is a common male malignancy. FAM107A, or actin-associated protein, is commonly downregulated in PCa and is associated with a poor patient prognosis. We investigated the role of FAM107A in PCa and found that downregulation of FAM107A expression was caused by hypermethylation of CpG islands, and DNA methyltransferase 1 (DNMT1) was involved in maintaining hypermethylation. Mechanistically, FAM107A regulated PCa cell growth through the FAK/PI3K/AKT signaling pathway. Therefore, FAM107A overexpression may represent a potential treatment for PCa, while therapies targeting epigenetic events that regulate FAM107A expression may also be an effective strategy for PCa treatment.

Abstract

Prostate cancer (PCa) is one of the most common cancers and is the second leading cause of mortality in men. Studies exploring novel therapeutic methods are urgently needed. FAM107A, a coding gene located in the short arm of chromosome3, is generally downregulated in PCa and is associated with a poor prognosis. However, the downregulation of FAM107A in PCa and the mechanism of its action remain challenging to determine. This investigation found that downregulation of FAM107A expression in PCa was caused by hypermethylation of CpG islands. Furthermore, DNA methyltransferase 1 (DNMT1) was involved in maintaining hypermethylation. Mechanistically, overexpression of FAM107A inhibits tumor cell proliferation, migration, invasion and promotes apoptosis through the FAK/PI3K/AKT signaling pathway, indicating that FAM107A may be a molecular brake of FAK/PI3K/AKT signaling, thus limiting the active state of the FAK/PI3K/AKT pathway. These findings will contribute to a better understanding of the effect of FAM107A in PCa, and FAM107A may represent a new therapeutic target for PCa.

Identification of the Putative Tumor Suppressor Characteristics of FAM107A via Pan-Cancer Analysis

Family with sequence similarity 107, member A(FAM107A) was supposed as a tumor suppressor for various types of tumors. However, no pan-cancer analysis of FAM107A is available. Therefore, we conducted a FAM107A-related pan-cancer analysis across thirty-three tumors based on TCGA database to explore the molecular characteristics of FAM107A. The FAM107A expression is reduced in most cancers, and its down-regulated expression was linked to poor overall survival and progression-free survival of tumor patients. Analysis of DNA methylation of the FAM107A gene showed a negative correlation between FAM107A expression and promoter methylation in numerous cancers. Furthermore, FAM107A expression was noted to be involved in myeloid-derived suppressor cell infiltration in multiple cancers. To explore the mechanism of FAM107A in cancers, KEGG, and GO enrichment analysis was performed and the result showed "cell adhesion" and "cAMP signaling pathway" terms as the potential impact of FAM107A on cancers. An experiment in vitro showed FAM107A knockdown promoted the proliferation, migration, and invasion of bladder cancer and renal cancer cells. Our study indicates that FAM107A may be a putative tumor suppressor in bladder cancer and other tumors.

Commander Complex-A Multifaceted Operator in Intracellular Signaling and Cargo

Commander complex is a 16-protein complex that plays multiple roles in various intracellular events in endosomal cargo and in the regulation of cell homeostasis, cell cycle and immune response. It consists of COMMD1-10, CCDC22, CCDC93, DENND10, VPS26C, VPS29, and VPS35L. These proteins are expressed ubiquitously in the human body, and they have been linked to diseases including Wilson's disease, atherosclerosis, and several types of cancer. In this review we describe the function of the commander complex in endosomal cargo and summarize the individual known roles of COMMD proteins in cell signaling and cancer. It becomes evident that commander complex might be a much more important player in intracellular regulation than we currently understand, and more systematic research on the role of commander complex is required.

Comprehensive analysis of expression, prognosis and immune infiltration for TIMPs in glioblastoma

Background

Tissue inhibitors of metalloproteinase (TIMP) family proteins are peptidases involved in extracellular matrix (ECM) degradation. Various diseases are related to TIMPs, and the primary reason is that TIMPs can indirectly regulate remodelling of the ECM and cell signalling by regulating matrix metalloproteinase (MMP) activity. However, the link between TIMPs and glioblastoma (GBM) is unclear.

Objective

This study aimed to explore the role of TIMP expression and immune infiltration in GBM.

Methods

Oncomine, GEPIA, OSgbm, LinkedOmics, STRING, GeneMANIA, Enrichr, and TIMER were used to conduct differential expression, prognosis, and immune infiltration analyses of TIMPs in GBM.

Results

All members of the TIMP family had significantly higher expression levels in GBM. High TIMP3 expression correlated with better overall survival (OS) and disease-specific survival (DSS) in GBM patients. TIMP4 was associated with a long OS in GBM patients. We found a positive relationship between TIMP3 and TIMP4, identifying gene sets with similar or opposite expression directions to those in GBM patients. TIMPs and associated genes are mainly associated with extracellular matrix organization and involve proteoglycan pathways in cancer. The expression levels of TIMPs in GBM correlate with the infiltration of various immune cells, including CD4+ T cells, macrophages, neutrophils, B cells, CD8⁺ T cells, and dendritic cells.

Conclusions

Our study inspires new ideas for the role of TIMPs in GBM and provides new directions for multiple treatment modalities, including immunotherapy, in GBM.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-021-02477-1.

Transcriptional analysis of the expression, prognostic value and immune infiltration activities of the COMMD protein family in hepatocellular carcinoma

BACKGROUND

The copper metabolism MURR1 domain (COMMD) protein family involved in tumor development and progression in several types of human cancer, but little is known about the function of COMMD proteins in hepatocellular carcinoma (HCC).

METHODS

The ONCOMINE and the UALCAN databases were used to evaluate the expression of COMMD1-10 in HCC and the association of this family with individual cancer stage and tumor grade. Kaplan-Meier (K-M) Plotter and Cox analysis hint the prognostic value of COMMDs. A network comprising 50 most similar genes and COMMD1-10 was constructed with the STRING database. Gene set enrichment analysis (GSEA) was performed using LinkedOmics database. The correlations between COMMD expression and the presence of immune infiltrating cells were also analyzed by the tumor immune estimation resource (TIMER) database. GSE14520 dataset and 80 HCC patients were used to validated the expression and survival value of COMMD3. Human HCC cell lines were also used for validating the function of COMMD3.

RESULTS

The expression of all COMMD family members showed higher expression in HCC tissues than that in normal tissues, and is associated with clinical cancer stage and pathological tumor grade. In HCC patients, the transcriptional levels of COMMD1/4 are positively correlated with overall survival (OS), while those of COMMD2/3/7/8/9 are negatively correlated with OS. Multivariate analysis indicated that a high level of COMMD3 mRNA is an independent prognostic factor for shorter OS in HCC patients. However, the subset of patients with grade 3 HCC, K-M survival curves revealed that high COMMD3/5/7/8/9 expression and low COMMD4/10 expression were associated with shorter OS. In addition, the expression of COMMD2/3/10 was associated with tumor-induced immune response activation and immune infiltration in HCC. The expression of COMMD3 from GSE14520 dataset and 80 patients are both higher in tumor than that in normal tissue, and a higher level of COMMD3 mRNA is associated with shorter OS. Knockdown of COMMD3 inhibits human HCC cell lines proliferation in vitro.

CONCLUSIONS

Our study indicates that COMMD3 is an independent prognostic biomarker for the survival of HCC patients. COMMD3 supports the proliferation of HCC cells and contributes to the poor OS in HCC patients.

Transcription factor SP1-induced microRNA-146b-3p facilitates the progression and metastasis of colorectal cancer via regulating FAM107A

BACKGROUND

Recent studies have provided compelling evidence regarding the association of microRNAs (miRNAs) with the progression and development of tumors. Among the miRNAs, the dysregulation of miR-146b-3p expression has been reported in several cancers, however, its effect on colorectal cancer (CRC) remains unexplored. Many studies have suggested a close correlation between the transcription factor (TF)-miRNA signal and cancer. The present study explored the effects of TF-miR-146b-3p axis on CRC and elucidated its downstream regulatory molecule.

MATERIALS AND METHODS

The expression levels of miR-146b-3p in CRC tissues and cell lines were assessed via quantitative real-time polymerase chain reaction (qRT-PCR). The impact of miR-146b-3p on CRC cell proliferation, migration, and invasion were analyzed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) cell proliferation assay and transwell migration and invasion assay. Additionally, the impact of miR-146b-3p on CRC cell cycle and apoptosis was investigated using flow cytometry. The targets of miR-146b-3p, predicted by miRWalk database, were verified using a dual-luciferase reporter system. The expression levels of TFs were detected using qRT-PCR. The effects of miR-146b-3p and SP1 on FAM107A expression were assessed by performing qRT-PCR and western blotting. Chromatin Immunoprecipitation (ChIP) Assay was performed and JASPAR database was utilized to explore the regulatory relationship between the SP1 and miR-146b-3p.

RESULTS

Increased expression of miR-146b-3p in CRC tissues and cell lines correlated with poor overall survival (OS). Upregulation of miR-146b-3p expression remarkably promoted the proliferation, migration, and invasion of CRC cells and suppressed their apoptosis. Furthermore, SP1 overexpression significantly elevated the miR-146b-3p expression, decreased the FAM107A expression, and promoted the G1/S transition. The miR-146b-3p overexpression also enhanced the effects of SP1 overexpression on CRC cell proliferation, migration, and invasion, whereas miR-146b-3p knockdown led to the opposite results.

CONCLUSION

Mechanistically, miR-146b-3p functions as an oncogene by directly targeting FAM107A. Our results highlight the critical regulatory role played by SP1-induced miR-146b-3p expression in CRC development. Our results suggest that SP1/miR-146b-3p/FAM107A axis may be a potential therapeutic target for CRC.

Overview of the molecular mechanisms of migration and invasion in glioblastoma multiforme

Glioblastoma (GBM) is one of the most devastating cancers, with an approximate median survival of only 16 months. Although some new insights into the fantastic heterogeneity of this kind of brain tumor have been revealed in recent studies, all subclasses of GBM still demonstrate highly aggressive invasion properties to the surrounding parenchyma. This behavior has become the main obstruction to current curative therapies as invasive GBM cells migrate away from these foci after surgical therapies. Therefore, this review aimed to provide a relatively comprehensive study of GBM invasion mechanisms, which contains an intricate network of interactions and signaling pathways with the extracellular matrix (ECM). Among these related molecules, TGF-β, the ECM, Akt, and microRNAs are most significant in terms of cellular procedures related to GBM motility and invasion. Moreover, we also review data indicating that Musashi-1 (MSI1), a neural RNA-binding protein (RBP), regulates GBM motility and invasion, maintains stem cell populations in GBM, and promotes drug-resistant GBM phenotypes by stimulating necessary oncogenic signaling pathways through binding and regulating mRNA stability. Importantly, these necessary oncogenic signaling pathways have a close connection with TGF-β, ECM, and Akt. Thus, it appears promising to find MSI-specific inhibitors or RNA interference-based treatments to prevent the actions of these molecules despite using RBPs, which are known as hard therapeutic targets. In summary, this review aims to provide a better understanding of these signaling pathways to help in developing novel therapeutic approaches with better outcomes in preclinical studies.

Downregulated in renal carcinoma 1 (DRR1) mediates the differentiation of neural stem cells through transcriptional regulation

Downregulated in renal carcinoma 1 (DRR1), also called family with sequence similarity 107, member A (FAM107A), is highly expressed in the nervous system. DRR1 has been found to be involved in neuronal survival, spine formation, and synaptic function. Recently, several studies have reported that DRR1 is expressed in neural stem cells (NSCs) and neural progenitor cells during the early stages of brain development. However, the mechanisms underlying the role and function of DRR1 in NSCs are poorly understood. To clarify the role of DRR1 in NSCs, we transfected DRR1 shRNA into primary NSCs and found that downregulation of DRR1 suppressed the differentiation of NSCs. To investigate the underlying mechanism in this case, chromatin immunoprecipitation sequencing (ChIP-seq) analysis was performed to identify the genes downstream of DRR1. Several genes, such as AHNAK, VAMP8, NOD1, and ACVR2B were identified to be downstream of DRR1 in NSCs.

COMMD1, a multi-potent intracellular protein involved in copper homeostasis, protein trafficking, inflammation, and cancer

Copper is a trace element indispensable for life, but at the same time it is implicated in reactive oxygen species formation. Several inherited copper storage diseases are described of which Wilson disease (copper overload, mutations in ATP7B gene) and Menkes disease (copper deficiency, mutations in ATP7A gene) are the most prominent ones. After the discovery in 2002 of a novel gene product (i.e. COMMD1) involved in hepatic copper handling in Bedlington terriers, studies on the mechanism of action of COMMD1 revealed numerous non-copper related functions. Effects on hepatic copper handling are likely mediated via interactions with ATP7B. In addition, COMMD1 has many more interacting partners which guide their routing to either the plasma membrane or, often in an ubiquitination-dependent fashion, trigger their proteolysis via the S26 proteasome. By stimulating NF-κB ubiquitination, COMMD1 dampens an inflammatory reaction. Finally, targeting COMMD1 function can be a novel approach in the treatment of tumors.

Down-regulated in renal cell carcinoma 1 (DRR1) regulates axon outgrowth during hippocampal neuron development

Down-regulated in renal cell carcinoma 1 (DRR1), a unique stress-induced protein, is highly expressed in the nervous system. This study investigated the roles of DRR1 in the brain by examining its expression pattern at different developmental stages of a rat brain and in cultured primary hippocampal neurons. High expression of DRR1 was observed in all developmental stages of a rat brain and cultured primary hippocampal neurons. We then focused on the role of DRR1 in promoting neurite outgrowth during the early stage of hippocampal neuron development. Results showed that down-regulation of DRR1 suppressed axon outgrowth. Mass spectrometry analysis revealed that tropomodulin-2 (Tmod2) is a novel binding partner of DRR1. Our results showed that both DRR1 and Tmod2 mediate axon formation during the early stage of hippocampal neuron development. Suppression of TMOD2 expression rescued the abnormal axon outgrowth induced by DRR1 knockdown during the early stage of hippocampal neuron development.

Does Subtelomeric Position of COMMD5 Influence Cancer Progression?

The COMMD proteins are a family of ten pleiotropic factors which are widely conserved throughout evolution and are involved in the regulation of many cellular and physiological processes. COMMD proteins are mainly expressed in adult tissue and their downregulation has been correlated with tumor progression and poor prognosis in cancer. Among this family, COMMD5 emerged as a versatile modulator of tumor progression. Its expression can range from being downregulated to highly up regulated in a variety of cancer types. Accordingly, two opposing functions could be proposed for COMMD5 in cancer. Our studies supported a role for COMMD5 in the establishment and maintenance of the epithelial cell phenotype, suggesting a tumor suppressor function. However, genetic alterations leading to amplification of COMMD5 proteins have also been observed in various types of cancer, suggesting an oncogenic function. Interestingly, COMMD5 is the only member of this family that is located at the extreme end of chromosome 8, near its telomere. Here, we review some data concerning expression and role of COMMD5 and propose a novel rationale for the potential link between the subtelomeric position of COMMD5 on chromosome 8 and its contrasting functions in cancer.

Phosphorylation regulates cullin-based ubiquitination in tumorigenesis

Cullin-RING ligases (CRLs) recognize and interact with substrates for ubiquitination and degradation, and can be targeted for disease treatment when the abnormal expression of substrates involves pathologic processes. Phosphorylation, either of substrates or receptors of CRLs, can alter their interaction. Phosphorylation-dependent ubiquitination and proteasome degradation influence various cellular processes and can contribute to the occurrence of various diseases, most often tumorigenesis. These processes have the potential to be used for tumor intervention through the regulation of the activities of related kinases, along with the regulation of the stability of specific oncoproteins and tumor suppressors. This review describes the mechanisms and biological functions of crosstalk between phosphorylation and ubiquitination, and most importantly its influence on tumorigenesis, to provide new directions and strategies for tumor therapy.

The HMGB1-2 Ovarian Cancer Interactome. The Role of HMGB Proteins and Their Interacting Partners MIEN1 and NOP53 in Ovary Cancer and Drug-Response

High mobility group box B (HMGB) proteins are overexpressed in different types of cancers such as epithelial ovarian cancers (EOC). We have determined the first interactome of HMGB1 and HMGB2 in epithelial ovarian cancer (the EOC-HMGB interactome). Libraries from the SKOV-3 cell line and a primary transitional cell carcinoma (TCC) ovarian tumor were tested by the Yeast Two Hybrid (Y2H) approach. The interactome reveals proteins that are related to cancer hallmarks and their expression is altered in EOC. Moreover, some of these proteins have been associated to survival and prognosis of patients. The interaction of MIEN1 and NOP53 with HMGB2 has been validated by co-immunoprecipitation in SKOV-3 and PEO1 cell lines. SKOV-3 cells were treated with different anti-tumoral drugs to evaluate changes in HMGB1, HMGB2, MIEN1 and NOP53 gene expression. Results show that combined treatment of paclitaxel and carboplatin induces a stronger down-regulation of these genes in comparison to individual treatments. Individual treatment with paclitaxel or olaparib up-regulates NOP53, which is expressed at lower levels in EOC than in non-cancerous cells. On the other hand, bevacizumab diminishes the expression of HMGB2 and NOP53. This study also shows that silencing of these genes affects cell-viability after drug exposure. HMGB1 silencing causes loss of response to paclitaxel, whereas silencing of HMGB2 slightly increases sensitivity to olaparib. Silencing of either HMGB1 or HMGB2 increases sensitivity to carboplatin. Lastly, a moderate loss of response to bevacizumab is observed when NOP53 is silenced.

Nutritional Exchanges Within Tumor Microenvironment: Impact for Cancer Aggressiveness

Neoplastic tissues are composed not only by tumor cells but also by several non-transformed stromal cells, such as cancer-associated fibroblasts, endothelial and immune cells, that actively participate to tumor progression. Starting from the very beginning of carcinogenesis, tumor cells, through the release of paracrine soluble factors and vesicles, i.e., exosomes, modify the behavior of the neighboring cells, so that they can give efficient support for cancer cell proliferation and spreading. A mandatory role in tumor progression has been recently acknowledged to metabolic deregulation. Beside undergoing a metabolic reprogramming coherent to their high proliferation rate, tumor cells also rewire the metabolic assets of their stromal cells, educating them to serve as nutrient donors. Hence, an alteration in the composition and in the flow rate of many nutrients within tumor microenvironment has been associated with malignancy progression. This review is focused on metabolic remodeling of the different cell populations within tumor microenvironment, dealing with reciprocal re-education through the symbiotic sharing of metabolites, behaving both as nutrients and as transcriptional regulators, describing their impact on tumor growth and metastasis.

Intrinsic Disorder of the BAF Complex: Roles in Chromatin Remodeling and Disease Development

The two-meter-long DNA is compressed into chromatin in the nucleus of every cell, which serves as a significant barrier to transcription. Therefore, for processes such as replication and transcription to occur, the highly compacted chromatin must be relaxed, and the processes required for chromatin reorganization for the aim of replication or transcription are controlled by ATP-dependent nucleosome remodelers. One of the most highly studied remodelers of this kind is the BRG1- or BRM-associated factor complex (BAF complex, also known as SWItch/sucrose non-fermentable (SWI/SNF) complex), which is crucial for the regulation of gene expression and differentiation in eukaryotes. Chromatin remodeling complex BAF is characterized by a highly polymorphic structure, containing from four to 17 subunits encoded by 29 genes. The aim of this paper is to provide an overview of the role of BAF complex in chromatin remodeling and also to use literature mining and a set of computational and bioinformatics tools to analyze structural properties, intrinsic disorder predisposition, and functionalities of its subunits, along with the description of the relations of different BAF complex subunits to the pathogenesis of various human diseases.

Prognosis and modulation mechanisms of COMMD6 in human tumours based on expression profiling and comprehensive bioinformatics analysis

Background

The Copper Metabolism MURR1 (COMM) domain family has been reported to play important roles in tumorigenesis. As a prototype for the COMMD family, the expression pattern and biological function of COMMD6 in human tumours remain unknown.

Methods

COMMD6 expression in BALB/c mice and human tissues was examined using real-time PCR and immunohistochemistry. Kaplan–Meier analysis was applied to evaluate the prognosis of COMMD6 in tumours. Competing endogenous RNA (ceRNA) and transcriptional regulation network were constructed based on differentially expressed mRNAs, microRNAs and long non-coding RNAs from the cancer genome atlas database. GO and KEGG enrichment analysis were used to explore the bioinformatics implication.

Results

COMMD6 expression was widely observed in BALB/c mice and human tissues, which predicted prognosis of cancer patients. Furthermore, we shed light on the underlying tumour promoting role and mechanism of COMMD6 by constructing a TEX41-miR-340-COMMD6 ceRNA network in head and neck squamous cell carcinoma and miR-218-CDX1-COMMD6 transcriptional network in cholangiocarcinoma. In addition, COMMD6 may modulate the ubiquitination and degradation of NF-κB subunits and regulate ribonucleoprotein and spliceosome complex biogenesis in tumours.

Conclusions

This study may help to elucidate the functions and mechanisms of COMMD6 in human tumours, providing a potential biomarker for tumour prevention and therapy.

A severe mouse model of spinal muscular atrophy develops early systemic inflammation

Spinal muscular atrophy (SMA) is a fatal genetic disease, mainly affecting children. A number of recent studies show, aside from lower motor neuron degeneration and atrophy of skeletal muscles, widespread defects present in the central nervous system (CNS) and peripheral non-neuronal cell types of SMA patients and mouse models, particularly of severe forms. However, molecular mechanisms underlying the multi-organ manifestations of SMA were hardly understood. Here, using histology, flow cytometry and gene expression analysis in both messenger RNA and protein levels in various tissues, we found that a severe SMA mouse model develops systemic inflammation in early symptomatic stages. SMA mice had an enhanced intestinal permeability, resulting in microbial invasion into the circulatory system. Expression of proinflammatory cytokines was increased in all tissues and the acute phase response in the liver was activated. Systemic inflammation further mobilized glucocorticoid signaling and in turn led to dysregulation of a large set of genes, including robust upregulation of FAM107A in the spinal cord, increased expression of which has been implicated in neurodegeneration. Moreover, we show that lipopolysaccharide challenge markedly suppressed survival of motor neuron 2 exon 7 splicing in all examined peripheral and CNS tissues, resulting in global survival of motor neuron level reduction. Therefore, we identified a novel pathological mechanism in a severe SMA mouse model, which affects phenotypic severity through multiple paths and should contribute to progression of broad neuronal and non-neuronal defects.

COMMD1 regulates cell proliferation and cell cycle progression by modulating p21 Cip1 levels

Copper metabolism MURR1 domain-containing 1 (COMMD1) is a protein that participates in multiple cellular processes, including copper homeostasis and nuclear factor kappa B (NF-κB) and hypoxia-inducible factor 1α (HIF-1α) signaling. The COMMD1 upstream regulators X-linked inhibitor of apoptosis protein (XIAP) and p300 and downstream targets such as NF-κB and HIF-1α are involved in the regulation of cell proliferation and cell cycle progression. However, whether COMMD1 regulates cell proliferation and the cell cycle remains unclear. In the present study, we demonstrated that both overexpression and knockdown of COMMD1 affected the proliferation of HEK293 cells, and the cell cycle assay revealed that ectopic expression of COMMD1 arrested the cell cycle at the G1 phase. Furthermore, western blot analysis showed that COMMD1 affected p21 Cip1 levels. Taken together, these results suggest that COMMD1 regulates cell proliferation and cell cycle progression by modulating p21 Cip1 levels. Abbreviations COMMD1: Copper metabolism MURR1 domain containing 1; XIAP: X chromosome-linked inhibitor of apoptosis protein; FCS: Fetal calf serum; WCE: Whole cell extracts; RT-PCR: Reverse transcription-polymerase chain reaction; HEK293: Human embryonic kidney 293; ShRNA: Short hairpin RNA; NF-κB: Nuclear factor kappa-light-chain-enhancer of activated B cells; ARF: Alternate reading frame protein product of the CDKN2A locus.

The Stress-Inducible Protein DRR1 Exerts Distinct Effects on Actin Dynamics

Cytoskeletal dynamics are pivotal to memory, learning, and stress physiology, and thus psychiatric diseases. Downregulated in renal cell carcinoma 1 (DRR1) protein was characterized as the link between stress, actin dynamics, neuronal function, and cognition. To elucidate the underlying molecular mechanisms, we undertook a domain analysis of DRR1 and probed the effects on actin binding, polymerization, and bundling, as well as on actin-dependent cellular processes. Methods: DRR1 domains were cloned and expressed as recombinant proteins to perform in vitro analysis of actin dynamics (binding, bundling, polymerization, and nucleation). Cellular actin-dependent processes were analyzed in transfected HeLa cells with fluorescence recovery after photobleaching (FRAP) and confocal microscopy. Results: DRR1 features an actin binding site at each terminus, separated by a coiled coil domain. DRR1 enhances actin bundling, the cellular F-actin content, and serum response factor (SRF)-dependent transcription, while it diminishes actin filament elongation, cell spreading, and actin treadmilling. We also provide evidence for a nucleation effect of DRR1. Blocking of pointed end elongation by addition of profilin indicates DRR1 as a novel barbed end capping factor. Conclusions: DRR1 impacts actin dynamics in several ways with implications for cytoskeletal dynamics in stress physiology and pathophysiology.

Copper Metabolism of Newborns Is Adapted to Milk Ceruloplasmin as a Nutritive Source of Copper: Overview of the Current Data

Copper, which can potentially be a highly toxic agent, is an essential nutrient due to its role as a cofactor for cuproenzymes and its participation in signaling pathways. In mammals, the liver is a central organ that controls copper turnover throughout the body, including copper absorption, distribution, and excretion. In ontogenesis, there are two types of copper metabolism, embryonic and adult, which maintain the balance of copper in each of these periods of life, respectively. In the liver cells, these types of metabolism are characterized by the specific expression patterns and activity levels of the genes encoding ceruloplasmin, which is the main extracellular ferroxidase and copper transporter, and the proteins mediating ceruloplasmin metalation. In newborns, the molecular genetic mechanisms responsible for copper homeostasis and the ontogenetic switch from embryonic to adult copper metabolism are highly adapted to milk ceruloplasmin as a dietary source of copper. In the mammary gland cells, the level of ceruloplasmin gene expression and the alternative splicing of its pre-mRNA govern the amount of ceruloplasmin in the milk, and thus, the amount of copper absorbed by a newborn is controlled. In newborns, the absorption, distribution, and accumulation of copper are adapted to milk ceruloplasmin. If newborns are not breast-fed in the early stages of postnatal development, they do not have this natural control ensuring alimentary copper balance in the body. Although there is still much to be learned about the neonatal consequences of having an imbalance of copper in the mother/newborn system, the time to pay attention to this problem has arrived because the neonatal misbalance of copper may provoke the development of copper-related disorders.

miR-155 inhibits the formation of hypertrophic scar fibroblasts by targeting HIF-1α via PI3K/AKT pathway

Hypertrophic scar (HS) is a serious skin fibrotic disease characterized by the excessive proliferation of fibroblasts and often considered as a kind of benign skin tumor. microRNA-155 (miR-155) is usually served as a promising marker in antitumor therapy. In view of the similarities of hypertrophic scar and tumor, it is predicted that miR-155 may be a novel therapeutic target in clinical trials. Here we found the expression levels of miR-155 was gradually down regulated and HIF-1α was upregulated in HS tissue and HS derived fibroblasts (HFs). And cell proliferation was inhibited when miR-155 was overexpressed or HIF-1α was silenced. Moreover, overexpression of miR-155 in HFs could reduce the expression of collagens in vitro and inhibit the collagen fibers arrangement in vivo, whereas miR-155 knockdown gave opposite results. Furthermore, we found that miR-155 directly targeted the HIF-1α, which could also independently inhibit the expression of collagens in vitro and obviously improved the appearance and architecture of the rabbit ear scar in vivo when it was silencing. Finally, we found that PI3K/AKT pathway was enrolled in these processes. Together, our results indicated that miR-155 was a critical regulator in the formation and development of hypertrophic scar and might be a potential molecular target for hypertrophic scar therapy.

DRR1 promotes glioblastoma cell invasion and epithelial-mesenchymal transition via regulating AKT activation

Metastatic invasion is the primary cause of treatment failure for GBM. EMT is one of the most important events in the invasion of GBM; therefore, understanding the molecular mechanisms of EMT is crucial for the treatment of GBM. In this study, high expression of DRR1 was identified to correlate with a shorter median overall and relapse-free survival. Loss-of-function assays using shDRR1 weakened the invasive potential of the GBM cell lines through regulation of EMT-markers. The expressions of p-AKT were significantly decreased after DRR-depletion in SHG44 and U373 cells. Moreover, the invasion was inhibited by the AKT inhibitor, MK-2206. The expression of Vimentin, N-cadherin, MMP-7, snail and slug was significantly inhibited by MK-2206, while the expression of E-cadherin was upregulated. Our results provide the first evidence that DRR1 is involved in GBM invasion and progression possibly through the induction of EMT activation by phosphorylation of AKT.