Dynamin 3: a new candidate tumor suppressor gene in hepatocellular carcinoma detected by triple combination array analysis

A mitochondria-related genes associated neuroblastoma signature - based on bulk and single-cell transcriptome sequencing data analysis, and experimental validation

Background

Neuroblastoma (NB), characterized by its marked heterogeneity, is the most common extracranial solid tumor in children. The status and functionality of mitochondria are crucial in regulating NB cell behavior. While the significance of mitochondria-related genes (MRGs) in NB is still missing in key knowledge.

Materials and methods

This study leverages consensus clustering and machine learning algorithms to construct and validate an MRGs-related signature in NB. Single-cell data analysis and experimental validation were employed to characterize the pivotal role of FEN1 within NB cells.

Results

MRGs facilitated the classification of NB patients into 2 distinct clusters with considerable differences. The constructed MRGs-related signature and its quantitative indicators, mtScore and mtRisk, effectively characterize the MRGs-related patient clusters. Notably, the MRGs-related signature outperformed MYCN in predicting NB patient prognosis and was adept at representing the tumor microenvironment (TME), tumor cell stemness, and sensitivity to the chemotherapeutic agents Cisplatin, Topotecan, and Irinotecan. FEN1, identified as the most contributory gene within the MRGs-related signature, was found to play a crucial role in the communication between NB cells and the TME, and in the developmental trajectory of NB cells. Experimental validations confirmed FEN1's significant influence on NB cell proliferation, apoptosis, cell cycle, and invasiveness.

Conclusion

The MRGs-related signature developed in this study offers a novel predictive tool for assessing NB patient prognosis, immune infiltration, stemness, and chemotherapeutic sensitivity. Our findings unveil the critical function of FEN1 in NB, suggesting its potential as a therapeutic target.

Proteomic Modulation in TGF-β-Treated Cholangiocytes Induced by Curcumin Nanoparticles

Curcumin is a natural polyphenol that exhibits a variety of beneficial effects on health, including anti-inflammatory, antioxidant, and hepato-protective properties. Due to its poor water solubility and membrane permeability, in the present study, we prepared and characterized a water-stable, freely dispersible nanoformulation of curcumin. Although the potential of curcumin nanoformulations in the hepatic field has been studied, there are no investigations on their effect in fibrotic pathological conditions involving cholangiocytes. Exploiting an in vitro model of transforming growth factor-β (TGF-β)-stimulated cholangiocytes, we applied the Sequential Window Acquisition of All Theoretical Mass Spectra (SWATH-MS)-based quantitative proteomic approaches to study the proteome modulation induced by curcumin nanoformulation. Our results confirmed the well-documented anti-inflammatory properties of this nutraceutic, highlighting the induction of programmed cell death as a mechanism to counteract the cellular damages induced by TGF-β. Moreover, curcumin nanoformulation positively influenced the expression of several proteins involved in TGF-β-mediated fibrosis. Given the crucial importance of deregulated cholangiocyte functions during cholangiopathies, our results provide the basis for a better understanding of the mechanisms associated with this pathology and could represent a rationale for the development of more targeted therapies.

Endocytosis in cancer and cancer therapy

Endocytosis is a complex process whereby cell surface proteins, lipids and fluid from the extracellular environment are packaged, sorted and internalized into cells. Endocytosis is also a mechanism of drug internalization into cells. There are multiple routes of endocytosis that determine the fate of molecules, from degradation in the lysosomes to recycling back to the plasma membrane. The overall rates of endocytosis and temporal regulation of molecules transiting through endocytic pathways are also intricately linked with signalling outcomes. This process relies on an array of factors, such as intrinsic amino acid motifs and post-translational modifications. Endocytosis is frequently disrupted in cancer. These disruptions lead to inappropriate retention of receptor tyrosine kinases on the tumour cell membrane, changes in the recycling of oncogenic molecules, defective signalling feedback loops and loss of cell polarity. In the past decade, endocytosis has emerged as a pivotal regulator of nutrient scavenging, response to and regulation of immune surveillance and tumour immune evasion, tumour metastasis and therapeutic drug delivery. This Review summarizes and integrates these advances into the understanding of endocytosis in cancer. The potential to regulate these pathways in the clinic to improve cancer therapy is also discussed.

Dynamins in human diseases: differential requirement of dynamin activity in distinct tissues

Dynamin, a 100-kDa GTPase, is one of the most-characterized membrane fission machineries catalyzing vesicle release from plasma membrane during endocytosis. The human genome encodes three dynamins: DNM1, DNM2 and DNM3, with high amino acid similarity but distinct expression patterns. Ever since the discoveries of dynamin mutations associated with human diseases in 2005, dynamin has become a paradigm for studying pathogenic mechanisms of mutant proteins from the aspects of structural biology, cell biology, model organisms as well as therapeutic strategy development. Here, we review the diseases and pathogenic mechanisms caused by mutations of DNM1 and DNM2, focusing on the activity requirement and regulation of dynamins in different tissues.

Genome-Wide DNA Methylation Differences between Bos indicus and Bos taurus

Disease risk is a persistent problem in domestic cattle farming, while economic traits are the main concern. This study aimed to reveal the epigenetic basis for differences between zebu (Bos indicus) and taurine cattle (Bos taurus) in disease, disease resistance, and economic traits, and provide a theoretical basis for the genetic improvement of domestic cattle. In this study, whole genome bisulfite sequencing (WGBS) was used to analyze the whole-genome methylation of spleen and liver samples from Yunnan zebu and Holstein cattle. In the genome-wide methylation pattern analysis, it was found that the methylation pattern of all samples was dominated by the CG type, which accounted for >94.9%. The DNA methylation levels of different functional regions and transcriptional elements in the CG background varied widely. However, the methylation levels of different samples in the same functional regions or transcriptional elements did not differ significantly. In addition, we identified a large number of differentially methylation region (DMR) in both the spleen and liver groups, of which 4713 and 4663 were annotated to functional elements, and most of them were annotated to the intronic and exonic regions of genes. GO and KEGG functional analysis of the same differentially methylation region (DMG) in the spleen and liver groups revealed that significantly enriched pathways were involved in neurological, disease, and growth functions. As a result of the results of DMR localization, we screened six genes (DNM3, INPP4B, PLD, PCYT1B, KCNN2, and SLIT3) that were tissue-specific candidates for economic traits, disease, and disease resistance in Yunnan zebu. In this study, DNA methylation was used to construct links between genotypes and phenotypes in domestic cattle, providing useful information for further screening of epigenetic molecular markers in zebu and taurine cattle.

Exosomal microRNA-23a-3p contributes to the progression of cholangiocarcinoma by interaction with Dynamin3

Cholangiocarcinoma (abbreviated as CCA) accounts for about 3% of digestive tract tumors, which is a rare disease with relatively low incidence. Herein, we firstly discovered overexpression of microRNA-23a-3p (abbreviated as miR-23a-3p) in CCA tissues, as well as cell lines via bioinformatics prediction. Next, by conducting miR-23a-3p knockdown system in HUCCT1 cells and miR-23a-3p overexpression system in RBE cells, we investigated the biological effects of miR-23a-3p. Based on our findings, inhibition of miR-23a-3p was able to prevent cancer cell proliferation via colony formation, CCK-8, as well as EdU assays. Moreover, invasion as well as migration abilities of cells was examined by transwell assay and wound healing test. Animal study further verified that knockdown miR-23a-3p slowed down tumor growth and lung metastasis. In addition, we identified cholangiocarcinoma cells transferred miR-23a-3p through exosomes by a series of assays. Functional experiments have confirmed that exosomal miR-23a-3p could benefit for cancer cell growth and metastasis, serving as a cancer promoting gene. Furthermore, we found Dynamin3 (abbreviated as DNM3) turned out to be a target of miR-23a-3p, while DNM3 was down-regulated in cholangiocarcinoma. Knockdown DNM3 accelerated cancer cell development. Collectively, our findings firstly pointed out that exosomal miR-23a-3p was conducive to the progression of cholangiocarcinoma by interaction with DNM3, which provided potential evidence for cancer treatment.

Expression of DNM3 is associated with good outcome in colorectal cancer

The aim of this study is to reveal the potential value of dynamin3 (DNM3) in colorectal cancer (CRC) evaluation of clinical diagnosis and prognosis. A total of 100 tissue samples were collected from 50 patients with stages I–IV, CRC tissues (n = 50) paired with non-cancerous adjacent colorectal tissues (n = 50). The expression levels of DNM3 were detected in 50 cases of CRC tissues and 50 cases of non-cancerous adjacent colorectal tissues by real-time fluorescent quantitative reverse transcription-polymerase chain reaction (RT-PCR). Immunohistochemical method (IHC) was conducted to semi-quantify the expression of DNM3 protein. Results showed that the relative expression of DNM3 mRNA in CRC tissues was 0.634-fold of that in non-cancerous adjacent colorectal tissues. The positive rate of DNM3 protein in CRC tissues (42.0%) was much lower than that in non-cancerous adjacent colorectal tissues (66.0%; P < 0.05). The expression level of DNM3 protein in CRC tissues was dependent on tumor size, degree of histological differentiation, and clinical stage (P < 0.05). The expression level of DNM3 mRNA in CRC tissues was significantly correlated with tumor size and pathology classification (P < 0.05). The research shows that detecting the expression of DNM3 helps in analyzing the tumor size, degree of histological differentiation, and clinical stage. Expression of DNM3 may be associated with good outcome in CRC.

Prediction of Key Candidate Genes for Platinum Resistance in Ovarian Cancer

Purpose

Ovarian cancer is one of the common malignant tumors of female reproductive organs, which seriously threatens the life and health of women. Resistance to chemotherapeutic drugs for ovarian cancer is the root cause of recurrence in most patients. The purpose of this study is to determine the differentially expressed genes of platinum resistance in ovarian cancer, and to screen out molecular targets and diagnostic markers that could be used to treat ovarian cancer platinum resistance.

Methods

We downloaded 5 gene microarray datasets GSE58470, GSE45553, GSE41499, GSE33482, and GSE15372 from the Gene Expression Omnibus database, all of which are associated with ovarian cancer platinum resistance. Subsequently, the intersection of the statistically significant differentially expressed genes in 5 gene chips was taken, and relevant bioinformatics and clinical parameters were performed on the screened differential genes. qRT-PCR was utilized to examine the mRNA expression levels in ovarian cancer sensitive and cisplatin-resistant cells.

Results

Three differential genes, IFI27, JAG1, DNM3, may be closely related to platinum resistance of ovarian cancer, were screened by microarray datasets. According to the combined verification of bioinformatics, clinical case analyses and experiments, it was inferred that the increased expression of DNM3 was beneficial to patients with platinum resistance, but the high expression of IFI27 and JAG1 may lead to the risk of platinum resistance.

Conclusion

IFI27, JAG1 and DNM3 screened by relevant gene chips may serve as new biomarkers of platinum resistance in ovarian cancer.

Dynamin 3 Inhibits the Proliferation of Non-small-Cell Lung Cancer Cells by Suppressing c-MET-GBR2-STAT3 Complex Formation

Dynamin 3 (DNM3) has gained increased attention ever since its potential as a tumor suppressor was reported. However, its action in lung cancer (LC) is undefined. In this study, the role of DNM3 in LC development was investigated. DNM3 expression was found to be downregulated in tumors of patients with LC, especially those with metastasis. The DNM3 downregulation enhanced the proliferative and metastatic ability of LC cells, whereas its upregulation had the opposite effects. In vivo xenograft experiments confirmed that lung tumors with lower DNM3 expression had higher growth and metastatic abilities. Mechanistic studies revealed that DNM3 interacts with growth factor receptor-bound protein 2 (GBR2), thereby interrupting tyrosine-protein kinase Met (c-MET)-GBR2-signal transducer and activator of transcription 3 (STAT3) complex formation, which suppressed STAT3 activation. Therefore, the absence of DNM3 frees GBR2 to activate STAT3, which regulates the expression of genes related to LC proliferation and metastasis (e.g., cyclin D1 and Snail family transcriptional repressor 1). Additionally, the c-MET inhibitor crizotinib effectively suppressed LC cell proliferation and migration in vitro and in vivo, even with DNM3 depleted. Therefore, our study has demonstrated the antitumor effect of DNM3 in LC and suggests that the inhibition of c-MET might be a promising strategy for treating those LC patients with low DNM3 expression.

TBX15 rs98422, DNM3 rs1011731, RAD51B rs8017304, and rs2588809 Gene Polymorphisms and Associations With Pituitary Adenoma

BACKGROUND

Pituitary adenoma (PA) is a benign tumor of parenchymal cells in the adenohypophysis, and it's development is strongly associated with genetic factors.This study aim was to find whether TBX15 rs98422, DNM3 rs1011731, RAD51B rs8017304, and rs2588809 single nucleotide polymorphisms can be associated with pituitary adenoma. While the TBX15 gene belongs to the T-box family of genes and is a transcription factor involved in many developmental processes, the DNM3 encodes a protein that is a member of the dynamin family with mechanochemical properties involved in actin-membrane processes, predominantly in membrane budding, and the RAD51B gene plays a significant role in homologous recombination in DNA repair for genome stability.

MATERIALS AND METHODS

The study enrolled 113 patients with pituitary adenoma and 283 healthy control subjects. DNA samples were extracted and purified from peripheral blood leukocytes. Genotyping was carried out using real-time polymerase chain reaction. The results were assessed using binomial logistic regression.

RESULTS

Our study revealed that RAD51B rs2588809 TT genotype could be associated with PA development in the co-dominant (OR=6.833; 95% CI=2.557-18.262; p<0.001) and recessive (OR=7.066; 95% CI=2.667-18.722; p<0.001) models. The same results were observed in females but not in males and PA without recurrence, while in PA with recurrence, no statistically significant results were obtained.

CONCLUSION

RAD51B rs2588809 TT genotype may increase the odds of PA development in women; it may also be associated with non-recurrent PA development.

Dynamin 3 overexpression suppresses the proliferation, migration and invasion of cervical cancer cells

Dynamin 3 (DNM3) functions as a tumor suppressor in various malignancies. However, the underlying mechanism of DNM3 in cervical cancer remains to be elucidated. The present study aimed to indicate the function of DNM3 in cervical cancer. The expression of DNM3 in cervical tissues and cells was measured using bioinformatics analysis, immunohistochemistry and reverse transcription-quantitative PCR. The pcDNA3.1 plasmid was used to overexpress DNM3 in SiHa and C33A cells. The effects of DNM3 overexpression on cell proliferation, migration, invasion and apoptosis was detected by the CCK-8, clone formation, Transwell, flow cytometry and western blotting assays. In the present study, it was revealed that DNM3 was expressed at significantly low levels in cervical cancer tissues and cell lines compared with normal cervical tissues and cell lines. In addition, the low expression of DNM3 was significantly associated with high pathological grading of cervical cancer. The overall survival rate of patients with low DNM3 expression was significantly improved compared with patients with high DNM3 expression. In addition, the overexpression of DNM3 significantly inhibited the proliferation, migration and invasion of cervical carcinoma cells and induced cell apoptosis. The findings of the present study further revealed that the overexpression of DNM3 may inhibit cell migration and invasion by inactivating the epithelial mesenchymal transition process. In summary, the present study demonstrated that DNM3 was a tumor suppressor in cervical cancer progression and that it may serve as a potential prognostic biomarker for patients with cervical carcinoma.

Specialised endocytic proteins regulate diverse internalisation mechanisms and signalling outputs in physiology and cancer

Although endocytosis was first described as the process mediating macromolecule or nutrient uptake through the plasma membrane, it is now recognised as a critical component of the cellular infrastructure involved in numerous processes, ranging from receptor signalling, proliferation and migration to polarity and stem cell regulation. To realise these varying roles, endocytosis needs to be finely regulated. Accordingly, multiple endocytic mechanisms exist that require specialised molecular machineries and an array of endocytic adaptor proteins with cell-specific functions. This review provides some examples of specialised functions of endocytic adaptors and other components of the endocytic machinery in different cell physiological processes, and how the alteration of these functions is linked to cancer. In particular, we focus on: (i) cargo selection and endocytic mechanisms linked to different adaptors; (ii) specialised functions in clathrin-mediated versus non-clathrin endocytosis; (iii) differential regulation of endocytic mechanisms by post-translational modification of endocytic proteins; (iv) cell context-dependent expression and function of endocytic proteins. As cases in point, we describe two endocytic protein families, dynamins and epsins. Finally, we discuss how dysregulation of the physiological role of these specialised endocytic proteins is exploited by cancer cells to increase cell proliferation, migration and invasion, leading to anti-apoptotic or pro-metastatic behaviours.

The Expression of Dynamin 1, 2, and 3 in Human Hepatocellular Carcinoma and Patient Prognosis

Background

The classical dynamin family consists of dynamin 1, 2, and 3, which have different expression levels in different tissues to regulate cell membrane fission and endocytosis. Recent studies have reported increased expression of dynamins in human cancer, but their expression in hepatocellular carcinoma (HCC) remains to be determined. This study aimed to investigate the expression of dynamin 1, 2, and 3 in tissue sections of human HCC using quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry.

Material/Methods

The expression of dynamin 1, 2, and 3 were investigated in 192 cases of HCC and 14 paired samples of HCC and adjacent normal liver tissue by qRT-PCR and immunohistochemistry. The clinical significance of dynamin 1, 2, and 3 were determined by correlating their expression levels with patient clinicopathological factors and survival rates. Independent prognostic factors were determined using the Cox regression hazard model.

Results

In tissue samples from 192 patients with HCC, the expression of dynamin 1, 2, and 3 were upregulated in 41.15%, 29.69%, and 8.33% of cases, respectively. Dynamin 1 had a significantly increased mRNA expression level in HCC compared with adjacent normal liver tissues and was significantly correlated with alpha fetoprotein (AFP) levels, T stage, and TNM stage. Only dynamin 1 expression was correlated with the reduced overall survival (OS), and was identified as an independent prognostic biomarker of human HCC.

Conclusions

Upregulation of dynamin 1 at the protein and mRNA level was an independent prognostic biomarker of reduced OS in patients with HCC.

Linc01278 inhibits the development of papillary thyroid carcinoma by regulating miR-376c-3p/DNM3 axis

Purpose

Papillary thyroid carcinoma (PTC) is the most common endocrine malignancy, and its incidence has continuously increased in recent years. Therefore, it is essential to develop more useful therapeutic strategies.

Methods

We collected 56 pairs of PTC tissues and adjacent normal tissues and determined the expression patterns of linc01278, miR-376c-3p and DNM3. In addition, we analyzed the relationship between linc01278 expression and pathological information of PTC patients. Furthermore, the effects of linc01278, miR-376c-3p and DNM3 overexpression on proliferation, clonality, apoptosis, migration and invasion of PTC cell lines TPC1 and BCPAP were evaluated. The dual luciferase reporter assay was used to confirm the direct interaction between miR-376c-3p and linc01278.

Results

Linc01278 and DNM3 were remarkably down-regulated in PTC tissues and cell lines, whereas miR-376c-3p was significantly up-regulated. In addition, lower linc01278 expression was associated with increased tumor size, lymph node metastasis and higher clinical stage. Linc01278 inhibited cell proliferation of PTC cells by inducing apoptosis, and demonstrated attenuating effects on migration and invasion abilities of PTC cells by regulating the EMT process. More importantly, dual luciferase reporter experiments demonstrated the direct interaction between miR-376c-3p and linc01278, which revealed that DNM3 was a novel target of miR-376c-3p. The miR-376c-3p mimic significantly promoted the proliferation, migration and invasion of PTC cells, and inhibited cell apoptosis. Overexpression of DNM3 abolished the effects of the miR-376c-3p mimic on PTC cells. DNM3 expression was negatively correlated with miR-376c-3p expression, but was positively correlated with linc01278 expression.

Conclusion

Overall, we found that linc01278 can act as a competing endogenous RNA (ceRNA) to sponge miR-376c-3p, thereby positively regulating DNM3 expression and ultimately acting as a tumor suppressor gene in PTC progression.

siPRDX2-elevated DNM3 inhibits the proliferation and metastasis of colon cancer cells via AKT signaling pathway

Purpose: We have previously reported that PRDX2 plays an oncogenic role in colon cancer. In this study, the mRNA expression profile of PRDX2 in HCT116 cells was investigated. Furthermore, we selected Dynamin 3 (DNM3), which is up-regulated by siPRDX2, to investigate its expression pattern and functions in colon cancer. Patients and methods: PRDX2 siRNA was transfected into HCT116 cells and the mRNA profile was tested by RNA-Sequencing. The expression of interest proteins was determined by Western blot. DNM3 expression in colon cancer tissues and para-carcinoma tissues was evaluated by Western blot and immunohistochemistry assays. Full-length cDNA of DNM3 was cloned into pcDNA3.1 and introduced into HCT116 and HT29 cells. Cell proliferation was tested by CCK-8 and colony formation assays. Cell invasion and migration were tested by transwell assays. Gelatin zymography was utilized for detection of MMP9 activity. Cell apoptosis was investigated with Annexin V/PI staining and flow cytometry and visualized with Hoechst/PI staining assay. All statistical analysis was performed with SPSS 17.0 software. Results: PRDX2 knockdown led to 210 up-regulated genes and 16 down-regulated genes in HCT116 cells. We also found that DNM3 expression was up-regulated following PRDX2 silencing in HCT116 and HT29 cells. In colon cancer patients, DNM3 was down-regulated and showed a significant association with pathologic grading. DNM3 overexpression inhibited cell proliferation and induced apoptosis in HCT116 and HT29 cells. Cell migration and invasion were also down-regulated in DNM3 overexpressing colon cancer cells, which might be due to the inhibition of MMP9 proteolytic activities. After thorough investigation of the potential mechanism involved, we hypothesized that DNM3 overexpression induced activation of the mitochondrial apoptosis pathway and inhibition of the AKT pathway. Conclusion: These data suggest that DNM3 is down-regulated in colon cancer, serving as a tumor suppressor. Our study provides new sights into the prognostic value and therapeutic application of DNM3 in colon cancer.

A Trans-Ethnic Genome-Wide Association Study of Uterine Fibroids

Uterine fibroids affect up to 77% of women by menopause and account for up to $34 billion in healthcare costs each year. Although fibroid risk is heritable, genetic risk for fibroids is not well understood. We conducted a two-stage case-control meta-analysis of genetic variants in European and African ancestry women with and without fibroids classified by a previously published algorithm requiring pelvic imaging or confirmed diagnosis. Women from seven electronic Medical Records and Genomics (eMERGE) network sites (3,704 imaging-confirmed cases and 5,591 imaging-confirmed controls) and women of African and European ancestry from UK Biobank (UKB, 5,772 cases and 61,457 controls) were included in the discovery genome-wide association study (GWAS) meta-analysis. Variants showing evidence of association in Stage I GWAS (P < 1 × 10^-5) were targeted in an independent replication sample of African and European ancestry individuals from the UKB (Stage II) (12,358 cases and 138,477 controls). Logistic regression models were fit with genetic markers imputed to a 1000 Genomes reference and adjusted for principal components for each race- and site-specific dataset, followed by fixed-effects meta-analysis. Final analysis with 21,804 cases and 205,525 controls identified 326 genome-wide significant variants in 11 loci, with three novel loci at chromosome 1q24 (sentinel-SNP rs14361789; P = 4.7 × 10^-8), chromosome 16q12.1 (sentinel-SNP rs4785384; P = 1.5 × 10^-9) and chromosome 20q13.1 (sentinel-SNP rs6094982; P = 2.6 × 10^-8). Our statistically significant findings further support previously reported loci including SNPs near WT1, TNRC6B, SYNE1, BET1L, and CDC42/WNT4. We report evidence of ancestry-specific findings for sentinel-SNP rs10917151 in the CDC42/WNT4 locus (P = 1.76 × 10^-24). Ancestry-specific effect-estimates for rs10917151 were in opposite directions (P-Het-between-groups = 0.04) for predominantly African (OR = 0.84) and predominantly European women (OR = 1.16). Genetically-predicted gene expression of several genes including LUZP1 in vagina (P = 4.6 × 10^-8), OBFC1 in esophageal mucosa (P = 8.7 × 10^-8), NUDT13 in multiple tissues including subcutaneous adipose tissue (P = 3.3 × 10^-6), and HEATR3 in skeletal muscle tissue (P = 5.8 × 10^-6) were associated with fibroids. The finding for HEATR3 was supported by SNP-based summary Mendelian randomization analysis. Our study suggests that fibroid risk variants act through regulatory mechanisms affecting gene expression and are comprised of alleles that are both ancestry-specific and shared across continental ancestries.

Construction of a recombinant eukaryotic expression vector containing DNM3 gene and its expression in colon cancer cells

Introduction

Dynamin 3 (DNM3) is a large GTPase that possesses mechanochemical properties and has been shown to be involved in malignancies. However, most studies about DNM3 are observational, and knowledge of the precise molecular mechanism of DNM3 remains limited.

Materials and methods

We constructed a PCDH-CMV-MCS-EF1a-GFP-Puro-DNM3 recombinant eukaryotic expression vector, which was then transfected into SW620 and LoVo cells. One cell line was divided into three groups. DNM3 mRNA and protein expression was analyzed by quantitative real-time PCR and Western blot assay. To investigate DNM3 biological activity in colon cancer SW620 and LoVo cell line, we performed cell proliferation, transwell migration, and invasion assay. Matrix metalloproteinase (MMP)-2 and MMP-9 protein expressions were detected by Western blot.

Result

We successfully constructed a PCDH-CMV-MCS-EF1a-GFP-Puro-DNM3 recombinant eukaryotic expression vector, and stable DNM3 expression was observed in SW620 and LoVo cell lines. The vector overexpressing DNM3 inhibited the proliferation, weak invasion, and migration ability of colon cancer SW620 and LoVo cells relative to those in the control group (all P<0.001). DNM3 downregulated the protein expression of MMP-2 and MMP-9.

Conclusion

DNM3 may weaken the malignant behavior of colon cancer and may have promoted the invasion and migration of colon cancer by regulating the expression of MMP-2 and MMP-9.

Distinct functions of dynamin isoforms in tumorigenesis and their potential as therapeutic targets in cancer

Dynamins and their related proteins participate in the regulation of neurotransmission, antigen presentation, receptor internalization, growth factor signalling, nutrient uptake, and pathogen infection. Recently, emerging findings have shown dynamin proteins can also contribute to the genesis of cancer. This up-to-date review herein focuses on the functionality of dynamin in cancer development. Dynamin 1 and 2 both enhance cancer cell proliferation, tumor invasion and metastasis, whereas dynamin 3 has tumor suppression role. Antisense RNAs encoded on the DNA strand opposite a dynamin gene regulate the function of dynamin, and manipulate oncogenes and tumor suppressor genes. Certain dynamin-related proteins are also upregulated in distinct cancer conditions, resulting in apoptotic resistance, cell migration and poor prognosis. Altogether, dynamins are potential biomarkers as well as representing promising novel therapeutic targets for cancer treatment. This study also summarizes the current available dynamin-targeted therapeutics and suggests the potential strategy based on signalling pathways involved, providing important information to aid the future development of novel cancer therapeutics by targeting these dynamin family members.

DNM3, p65 and p53 from exosomes represent potential clinical diagnosis markers for glioblastoma multiforme

Background:

Glioblastoma multiforme (GBM) is the most aggressive and deadly primary brain cancer that arises from astrocytes and classified as grade IV. Recently, exosomes have been reported as an essential mediator in diverse cancer carcinogenesis and metastasis. However, their role in GBM is still unclear. In this study, we aimed to investigate whether blood exosomes can be potential clinical diagnostic markers for GBM.

Methods:

We used a xenograft orthotopic mouse model to detect the differentially expressed genes in the brain and blood exosomes of original/recurrent GBM.

Results:

We found that recurrent GBM had stronger growth capacity and lethality than original GBM in the mouse model. A gene microarray of original tumors and blood exosomes from GBM orthotopic xenografts results showed that DNM3, p65 and CD117 expressions increased, whereas PTEN and p53 expressions decreased in both original tumors and blood exosomes. In the recurrent GBM tumor model, DNM3 and p65 showed increased expressions, whereas ST14 and p53 showed decreased expressions in tumor and blood exosomes of the recurrent GBM mouse model.

Conclusion:

In summary, we found that DNM3, p65 and p53 had a similar trend in brain and blood exosomes both for original and recurrent GBM, and could serve as potential clinical diagnostic markers for GBM.

Dynamin 3 suppresses growth and induces apoptosis of hepatocellular carcinoma cells by activating inducible nitric oxide synthase production

Dynamin 3 (DNM3) is candidate tumor suppressor against hepatocellular carcinoma (HCC). Downregulation of DNM3 is more frequently identified in HCC tissues than in normal liver tissues. However, the mechanism underlying DNM3-mediated inhibition of HCC remains unclear. The present study demonstrated that DNM3 expression was decreased in human HCC tissues and cell lines. The downregulation of DNM3 promoted cell proliferation by increasing cell cycle-associated proteins, including cyclin D1, cyclin-dependent kinase (CDK) 2 and CDK4. The upregulation of DNM3 induced HCC cell apoptosis and inhibited tumor growth. The present study also revealed that overexpression of DNM3 induced nitric oxide (NO) production and intracellular reactive oxygen species (ROS) accumulation. DNM3 overexpression also increased the protein expression level of inducible nitric oxide synthase (iNOS) in HCC cells and subcutaneous HCC tumor xenografts. The inhibition of iNOS by L-canavanine attenuated the DNM3-induced ROS accumulation and apoptotic cell death. In conclusion, the results indicate that DNM3 overexpression may induce apoptosis and inhibit tumor growth of HCC by activating iNOS production and the subsequent NO-ROS signaling pathways.

Dynamin Functions and Ligands: Classical Mechanisms Behind

Dynamin is a GTPase that plays a vital role in clathrin-dependent endocytosis and other vesicular trafficking processes by acting as a pair of molecular scissors for newly formed vesicles originating from the plasma membrane. Dynamins and related proteins are important components for the cleavage of clathrin-coated vesicles, phagosomes, and mitochondria. These proteins help in organelle division, viral resistance, and mitochondrial fusion/fission. Dysfunction and mutations in dynamin have been implicated in the pathophysiology of various disorders, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, Charcot-Marie-Tooth disease, heart failure, schizophrenia, epilepsy, cancer, dominant optic atrophy, osteoporosis, and Down's syndrome. This review is an attempt to illustrate the dynamin-related mechanisms involved in the above-mentioned disorders and to help medicinal chemists to design novel dynamin ligands, which could be useful in the treatment of dynamin-related disorders.

Exosomal miR-221 targets DNM3 to induce tumor progression and temozolomide resistance in glioma

MicroRNA is an important regulator of glioblastoma. This study aims at validating microRNA-221 (miR-221) as a biomarker for glioblastoma, and understanding how miR-221 regulates glioblastoma progression. Using clinical samples, miR-221 expression was analyzed by quantitative reverse-transcriptase PCR (qPCR). SHG-44 cells were treated with anti-miR-221 or U87MG-derived exosomes followed by monitoring changes in cell viability, migration and temozolomide (TMZ) resistance. Bioinformatics approach was used to identify targets of miR-221. The interaction between miR-221 and its target, DNM3 gene, was studied with dual-luciferase reporter assay, Spearman's correlation analysis, and western blotting. To verify that RELA regulates miR-221 expression, RELA-expressing vector or shRNA was introduced into SHG-44 cells and its effect on miR-221 expression was monitored. Both tissue-level and exosomal miR-221 expression increased with glioma grades. In SHG-44 cells, downregulating miR-221 expression inhibited cell proliferation, migration, and TMZ resistance, whereas incubation with U87MG-derived exosomes exerted tumor-promoting effects. DNM3 gene is a target of miR-221. RELA induced miR-221 expression. In glioma, elevated miR-221 expression is a biomarker for glioma. DNM3 is a target of miR-221 and RELA regulates miR-221 expression. The RELA/miR-221 axis is a target for glioma diagnosis and therapy.

Molecular alterations in the carcinogenesis and progression of hepatocellular carcinoma: Tumor factors and background liver factors

Although hepatocellular carcinoma (HCC) is associated with poor prognosis worldwide, the molecular mechanisms underlying the carcinogenesis and progression of this disease remain unclear. Several tumor characteristics have previously been demonstrated to be prognostic factors of survival following hepatic resection, or the recurrence of HCC or other types of cancer. Comparisons of normal tissues and HCC tumor tissues have revealed the presence of numerous molecular alterations in HCC, including genetic and epigenetic mechanisms, particularly mutations in certain genes and DNA methylation in the promoter regions of tumor-suppressor genes. A number of studies have previously used array analysis to detect variations in the expression levels of cancer-associated genes and microRNAs, and in DNA methylation. However, an investigation of HCC tumor tissues may not determine the effect of noncancerous liver tissues (background liver) in patients with HCC. As HCC may recur multicentrically following resection, a damaged or chronically diseased HCC background liver may be considered as a pre-cancerous organ. Therefore, the influence of the background liver on HCC requires further study. Detailed studies regarding the background liver may be essential for the improved understanding of the carcinogenesis and progression of this malignancy; however only a few studies have investigated the microenvironment of the HCC background liver. The present review discusses prior molecular studies of hepatocarcinogenesis that focus on HCC and background liver tissues.

DNM3 Attenuates Hepatocellular Carcinoma Growth by Activating P53

BACKGROUND

Primary hepatocellular carcinoma is one of the most common malignant tumors in China and its mortality rate shows no sign at present of ceasing to rise. In our previous study, we found that the mRNA level of Dynamin3 (DNM3), a member of the Dynamin family, is significantly lower in hepatocellular carcinoma tissues than in non-tumor tissues. The aim of this study was to investigate the expression pattern and potential function of DNM3 in hepatocellular carcinoma.

MATERIAL/METHODS

First, we determined the expression ofDNM3 in human hepatocellular carcinoma tissues and cell lines. We then studied the biological function of DNM3 on hepatocellular carcinoma cells by proliferation assay and colony formation assay. Flow cytometry was used to study the effect of DNM3 on cell cycle and apoptosis.

RESULTS

Expression of DNM3 was significantly downregulated in hepatocellular carcinoma tissues and was associated with vein invasion and tumor metastasis. In addition, upregulation of DNM3 reduced hepatocellular carcinoma cell proliferation and colony formation, induced hepatocellular carcinoma cell G0/G1 phase arrest, and stimulated hepatocellular carcinoma cell apoptosis. We also found that DNM3 may exert its anti-proliferative effect through upregulating p53.

CONCLUSIONS

Our findings suggest that DNM3 attenuates the proliferation and induces apoptosis of gastric cancer cells. Modulation of DNM3 may prove to be an efficient method of hepatocellular carcinoma treatment.

Genomic-Wide Analysis with Microarrays in Human Oncology

DNA microarray technologies have advanced rapidly and had a profound impact on examining gene expression on a genomic scale in research. This review discusses the history and development of microarray and DNA chip devices, and specific microarrays are described along with their methods and applications. In particular, microarrays have detected many novel cancer-related genes by comparing cancer tissues and non-cancerous tissues in oncological research. Recently, new methods have been in development, such as the double-combination array and triple-combination array, which allow more effective analysis of gene expression and epigenetic changes. Analysis of gene expression alterations in precancerous regions compared with normal regions and array analysis in drug-resistance cancer tissues are also successfully performed. Compared with next-generation sequencing, a similar method of genome analysis, several important differences distinguish these techniques and their applications. Development of novel microarray technologies is expected to contribute to further cancer research.

CCNJ detected by triple combination array analysis as a tumor-related gene of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has a high likelihood of recurrence and a poor prognosis. To detect cancer-related genes of HCC, we developed a new technique: triple combination array analysis, consisting of a methylation array, a gene expression array and a single nucleotide polymorphism array. A surgical specimen obtained from a 68-year-old female HCC patient was analyzed using triple combination array, which identified cyclin J (CCNJ) as a candidate cancer-related gene of HCC. Subsequently, samples from 85 HCC patients were evaluated for CCNJ promoter hypermethylation and expression status using methylation-specific PCR (MSP) and quantitative reverse transcriptase RT-PCR, respectively. CCNJ was found to be hypermethylated (methylation value, 0.906; range, 0-1.0) in cancer tissue, compared with adjacent non-cancerous tissue (0.112) using a methylation array. MSP revealed that CCNJ was hypermethylated in 67 (78.8%) of the tumor samples. CCNJ expression was significantly decreased in cases with hypermethylation (P<0.0001). Furthermore, cases with both promoter hypermethylation and decreased expression of CCNJ in the tumor tissue had a worse overall survival than the other cases (P=0.0383). In conclusion, our results indicated that CCNJ could be a novel prognostic marker of HCC, and this study indicated that triple combination array analysis was effective in detecting new tumor-related genes and their mechanisms.

The CpG island methylator phenotype in breast cancer is associated with the lobular subtype

BACKGROUND

Aberrations in DNA methylation patterns are well-described in human malignancies. However, the existence of the 'CpG island methylator phenotype' (CIMP) in human breast cancer is still controversial.

MATERIALS & METHODS

Illumina's HumanMethylation 450K BeadChip was used to analyze genome-wide DNA methylation patterns. Chromosomal abnormalities were determined by array-based CGH.

RESULTS

Invasive lobular breast carcinomas exhibit the highest number of differentially methylated CpG sites and a strong inverse correlation of aberrant DNA hypermethylation and copy number alterations. Nine differentially methylated regions within seven genes discriminating the investigated subgroups were identified and validated in an independent validation cohort and correlated to a better relapse-free survival.

CONCLUSION

These results depict a clear difference between genetically and epigenetically unstable breast carcinomas indicating different ways of tumor progression and/or initiation, which strongly supports the association of CIMP with the lobular subtype and provide new options for detection and therapy.

Identification of the collagen type 1 α 1 gene (COL1A1) as a candidate survival-related factor associated with hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) is one of the major causes of cancer-related death especially among Asian and African populations. It is urgent that we identify carcinogenesis-related genes to establish an innovative treatment strategy for this disease.

Methods

Triple-combination array analysis was performed using one pair each of HCC and noncancerous liver samples from a 68-year-old woman. This analysis consists of expression array, single nucleotide polymorphism array and methylation array. The gene encoding collagen type 1 alpha 1 (COL1A1) was identified and verified using HCC cell lines and 48 tissues from patients with primary HCC.

Results

Expression array revealed that COL1A1 gene expression was markedly decreased in tumor tissues (log₂ ratio –1.1). The single nucleotide polymorphism array showed no chromosomal deletion in the locus of COL1A1. Importantly, the methylation value in the tumor tissue was higher (0.557) than that of the adjacent liver tissue (0.008). We verified that expression of this gene was suppressed by promoter methylation. Reactivation of COL1A1 expression by 5-aza-2′-deoxycytidine treatment was seen in HCC cell lines, and sequence analysis identified methylated CpG sites in the COL1A1 promoter region. Among 48 pairs of surgical specimens, 13 (27.1%) showed decreased COL1A1 mRNA expression in tumor sites. Among these 13 cases, 10 had promoter methylation at the tumor site. The log-rank test indicated that mRNA down-regulated tumors were significantly correlated with a poor overall survival rate (P = 0.013).

Conclusions

Triple-combination array analysis successfully identified COL1A1 as a candidate survival-related gene in HCCs. Epigenetic down-regulation of COL1A1 mRNA expression might have a role as a prognostic biomarker of HCC.