DEPDC1B knockdown inhibits the development of malignant melanoma through suppressing cell proliferation and inducing cell apoptosis

Targeting colorectal cancer at the level of nuclear pore complex

BACKGROUND

Nuclear pore complexes (NPCs) are the architectures entrenched in nuclear envelop of a cell that regulate the nucleo-cytoplasmic transportation of materials, such as proteins and RNAs for proper functioning of a cell. The appropriate localization of proteins and RNAs within the cell is essential for its normal functionality. For such a complex transportation of materials across the NPC, around 60 proteins are involved comprising nucleoporins, karyopherins and RAN system proteins that play a vital role in NPC's structure formation, cargo translocation across NPC, and cargoes' rapid directed transportation respectively. In various cancers, the structure and function of NPC is often exaggerated, following altered expressions of its nucleoporins and karyopherins, affecting other proteins of associated signaling pathways. Some inhibitors of karyopherins at present, have potential to regulate the altered level/expression of these karyopherin molecules.

AIM OF REVIEW

This review summarizes the data from 1990 to 2023, mainly focusing on recent studies that illustrate the structure and function of NPC, the relationship and mechanisms of nucleoporins and karyopherins with colorectal cancer, as well as therapeutic values, in order to understand the pathology and underlying basis of colorectal cancer associated with NPC. This is the first review to our knowledge elucidating the detailed updated studies targeting colorectal cancer at NPC. The review also aims to target certain karyopherins, Nups and their possible inhibitors and activators molecules as a therapeutic strategy.

KEY SCIENTIFIC CONCEPTS OF REVIEW

NPC structure provides understanding, how nucleoporins and karyopherins as key molecules are responsible for appropriate nucleocytoplasmic transportation. Many studies provide evidences, describing the role of disrupted nucleoporins and karyopherins not only in CRC but also in other non-hematological and hematological malignancies. At present, some inhibitors of karyopherins have therapeutic potential for CRC, however development of more potent inhibitors may provide more effective therapeutic strategies for CRC in near future.

Platycodin D inhibits glioblastoma cell proliferation, migration, and invasion by regulating DEPDC1B-mediated epithelial-to-mesenchymal transition

BACKGROUND

Platycodin D (PD) is a potent bioactive constituent in the medicinal herb Platycodon grandiflorum. It has shown anticancer properties, particularly against glioblastoma (GB) and other human malignancies. DEPDC1B (DEP domain-containing protein 1B) is an oncogene associated with epithelial-mesenchymal transition (EMT). It is highly expressed in GB and correlated with tumor grade and patient prognosis. In this study, we investigated whether the antiglioma effect of PD was associated with downregulation of DEPDC1B.

METHODS

Gene expression and clinical data were obtained from the China Glioma Genome Atlas and The Cancer Genome Atlas databases for glioma samples. In vitro experiments were conducted using Cell Counting Kit-8 and Transwell assays to assess the impact of PD on the proliferation, migration, and invasion of GB cells. mRNA and protein expression was evaluated using real-time polymerase chain reaction and western blotting, respectively.

RESULTS

PD exerted inhibitory effects on the proliferation and motility of GB cells. PD downregulated DEPDC1B protein as well as several markers associated with EMT, namely N-cadherin, vimentin, and Snail. The suppressive effects of PD were enhanced when DEPDC1B was knocked down in GB cells, while overexpression of DEPDC1B in cells reversed the inhibitory effects of PD.

CONCLUSION

PD exerts an antiglioma effect by regulating DEPDC1B-mediated EMT.

DEPDC1B promotes development of cholangiocarcinoma through enhancing the stability of CDK1 and regulating malignant phenotypes

Cholangiocarcinoma (CCA) is the second most common primary tumor of the hepatobiliary system. At present, the therapeutic efficiency of cholangiocarcinoma is fairly low and the prognosis is poor. The root cause is that the molecular mechanism of the occurrence and development of CCA is largely unclear. This work intended to clarify the role of DEP domain-containing protein 1B (DEPDC1B) in the progress of CCA through cellular biology research strategies and further clarify the molecular mechanism of CCA. Clinical tissue-related detection showed that the expression level of DEPDC1B in tumor tissues was significantly higher than that in normal tissues and was positively correlated with tumor grade. Knockdown of the endogenous DEPDC1B of CCA cells can significantly inhibit cell proliferation and migration, while promoting cell apoptosis and blocking the cell cycle. DEPDC1B overexpression induced the opposite effects. Studies in animal models also showed that the downregulation of DEPDC1B can reduce the tumorigenicity of CCA cells. In addition, through gene profiling analysis and molecular biology studies, we found that CDK1 may be an important downstream mediator of DEPDC1B, the protein stability of which was significantly decreased through the ubiquitin-proteasome system in DEPDC1B knockdown cells. Moreover, knockdown of CDK1 can weaken the promotion of CCA caused by DEPDC1B overexpression. In summary, our research showed that DEPDC1B plays an important role in the development of CCA and its targeted inhibition may become one of the important methods to inhibit the progress of CCA.

Integrative QTL mapping and selection signatures in Groningen White Headed cattle inferred from whole-genome sequences

Here, we aimed to identify and characterize genomic regions that differ between Groningen White Headed (GWH) breed and other cattle, and in particular to identify candidate genes associated with coat color and/or eye-protective phenotypes. Firstly, whole genome sequences of 170 animals from eight breeds were used to evaluate the genetic structure of the GWH in relation to other cattle breeds by carrying out principal components and model-based clustering analyses. Secondly, the candidate genomic regions were identified by integrating the findings from: a) a genome-wide association study using GWH, other white headed breeds (Hereford and Simmental), and breeds with a non-white headed phenotype (Dutch Friesian, Deep Red, Meuse-Rhine-Yssel, Dutch Belted, and Holstein Friesian); b) scans for specific signatures of selection in GWH cattle by comparison with four other Dutch traditional breeds (Dutch Friesian, Deep Red, Meuse-Rhine-Yssel and Dutch Belted) and the commercial Holstein Friesian; and c) detection of candidate genes identified via these approaches. The alignment of the filtered reads to the reference genome (ARS-UCD1.2) resulted in a mean depth of coverage of 8.7X. After variant calling, the lowest number of breed-specific variants was detected in Holstein Friesian (148,213), and the largest in Deep Red (558,909). By integrating the results, we identified five genomic regions under selection on BTA4 (70.2-71.3 Mb), BTA5 (10.0-19.7 Mb), BTA20 (10.0-19.9 and 20.0-22.7 Mb), and BTA25 (0.5-9.2 Mb). These regions contain positional and functional candidate genes associated with retinal degeneration (e.g., CWC27 and CLUAP1), ultraviolet protection (e.g., ERCC8), and pigmentation (e.g. PDE4D) which are probably associated with the GWH specific pigmentation and/or eye-protective phenotypes, e.g. Ambilateral Circumocular Pigmentation (ACOP). Our results will assist in characterizing the molecular basis of GWH phenotypes and the biological implications of its adaptation.

Insights from DOCK2 in cell function and pathophysiology

Dedicator of cytokinesis 2 (DOCK2) can activate the downstream small G protein Rac and regulate cytoskeletal reorganization. DOCK2 is essential for critical physiological processes such as migration, activation, proliferation, and effects of immune cells, including lymphocytes, neutrophils, macrophages, and dendritic cells. For example, DOCK2 is involved in the development and activation of T and B lymphocytes by affecting synapse formation and inhibiting the development of the Th2 lineage by downregulating IL-4Rα surface expression. Not only that, DOCK2 may be a molecular target for controlling cardiac transplant rejection and Alzheimer’s disease (AD). Patients with defects in the DOCK2 gene also exhibit a variety of impaired cellular functions, such as chemotactic responses of lymphocytes and reactive oxygen species (ROS) production by neutrophils. To date, DOCK2 has been shown to be involved in the development of various diseases, including AD, pneumonia, myocarditis, colitis, tumors, etc. DOCK2 plays different roles in these diseases and the degree of inflammatory response has a different impact on the progression of disease. In this paper, we present a review of recent advances in the function of DOCK2 in various immune cells and its role in various diseases.

High Expression of DEPDC1B Predicts Poor Prognosis in Lung Adenocarcinoma

Introduction

Lung adenocarcinoma (LUAD) is the most common type of lung cancer. DEP domain-containing 1 B (DEPDC1B) is involved in the development of several cancers; however, its role in LUAD is unknown. Therefore, we aimed to determine the biological function and prognostic value of DEPDC1B in LUAD.

Material and Methods

We analyzed the correlation between DEPDC1B expression and the clinical features of LUAD and lung squamous cell carcinoma (LUSC). Survival was evaluated by generating Kaplan-Meier curves, which were used to analyze the relationship between DEPDC1B expression and prognosis in LUAD and LUSC. DEPDC1B expression in tumor and normal tissues from patients with LUAD and LUSC was determined using immunohistochemistry, and its clinical significance was analyzed. Finally, the correlation between the expression and biological function of DEPDC1B in LUAD was examined.

Results

Our findings revealed that DEPDC1B expression was higher in tumor tissues than that in normal tissues from patients with LUAD and LUSC (P < 0.001). These results were confirmed in clinical samples from patients using immunohistochemistry. Analysis of a dataset from The Cancer Genome Atlas (TCGA) showed that high DEPDC1B expression was associated with poor prognosis only in patients with LUAD (P < 0.001). Similarly, high DEPDC1B expression was related to shorter overall survival (OS) and progression-free interval (PFI) in patients with LUAD. These associations were not observed in LUSC. Functional enrichment analysis suggested that DEPDC1B promoted tumor development in LUAD by regulating the cell cycle.

Conclusion

High DEPDC1B expression predicts poor prognosis in patients with LUAD. Thus, DEPDC1B has potential as a therapeutic target for LUAD.

DEPDC1B collaborates with GABRD to regulate ESCC progression

Background

Esophageal squamous cell carcinoma (ESCC) is the leading cause of cancer-related death worldwide with a poor prognosis. Given that DEPDC1B plays a key role in multiple cancers, the role of this molecule in ESCC was explored to identify potential targets for ESCC patients.

Method

The expression level of DEPDC1B in ESCC was revealed based on the TCGA database and immunohistochemical experiments on clinical tissues. The correlation between DEPDC1B and survival of ESCC patients was analyzed by Kaplan–Meier method. Small hairpin RNA (shRNA)-mediated silencing of DEPDC1B expression in ESCC cells and performed a series of in vitro and in vivo functional validations.

Result

DEPDC1B was overexpressed in ESCC. High expression of DEPDC1B was significantly negatively correlated with overall survival in patients with ESCC. Moreover, knockdown of DEPDC1B inhibited ESCC cell proliferation, clone formation, migration, tumor formation and promoted apoptosis. Furthermore, knockdown of DEPDC1B leaded to significant downregulation of GABRD in ESCC cells. Meanwhile, GABRD expression was upregulated in ESCC, and its silencing can inhibit the proliferation and migration of the tumor cells. Interestingly, there was a protein interaction between DEPDC1B and GABRD. Functionally, GABRD knockdown partially reversed the contribution of DEPDC1B to ESCC progression. In addition, GABRD regulated ESCC progression may depend on PI3K/AKT/mTOR signaling pathway.

Conclusion

DEPDC1B collaborated with GABRD to regulate ESCC progression, and inhibition of this signaling axis may be a potential therapeutic target for ESCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02593-z.

DEPDC1B Promotes Melanoma Angiogenesis and Metastasis through Sequestration of Ubiquitin Ligase CDC16 to Stabilize Secreted SCUBE3

The ability of melanoma to acquire metastasis through the induction of angiogenesis is one of the major causes of skin cancer death. Here, it is found that high transcript levels of DEP domain containing 1B (DEPDC1B) in cutaneous melanomas are significantly associated with a poor prognosis. Tissue microarray analysis indicates that DEPDC1B expression is positively correlated with SOX10 in the different stages of melanoma. Consistently, DEPDC1B is both required and sufficient for melanoma growth, metastasis, angiogenesis, and functions as a direct downstream target of SOX10 to partly mediate its oncogenic activity. In contrast to other tumor types, the DEPDC1B-mediated enhancement of melanoma metastatic potential is not dependent on the activities of RHO GTPase signaling and canonical Wnt signaling, but is acquired through secretion of signal peptide, CUB domain and EGF like domain containing 3 (SCUBE3), which is crucial for promoting angiogenesis in vitro and in vivo. Mechanistically, DEPDC1B regulates SCUBE3 protein stability through the competitive association with ubiquitin ligase cell division cycle 16 (CDC16) to prevent SCUBE3 from undergoing degradation via the ubiquitin-proteasome pathway. Importantly, expression of SOX10, DEPDC1B, and SCUBE3 are positively correlated with microvessel density in the advanced stage of melanomas. In conclusion, it is revealed that a SOX10-DEPDC1B-SCUBE3 regulatory axis promotes melanoma angiogenesis and metastasis, which suggests that targeting secreted SCUBE3 can be a therapeutic strategy against metastatic melanoma.

Identification and Validation of DEPDC1B as an Independent Early Diagnostic and Prognostic Biomarker in Liver Hepatocellular Carcinoma

Liver hepatocellular carcinoma (LIHC) is one of the most lethal tumors worldwide, and while its detailed mechanism of occurrence remains unclear, an early diagnosis of LIHC could significantly improve the 5-years survival of LIHC patients. It is therefore imperative to explore novel molecular markers for the early diagnosis and to develop efficient therapies for LIHC patients. Currently, DEPDC1B has been reported to participate in the regulation of cell mitosis, transcription, and tumorigenesis. To explore the valuable diagnostic and prognostic markers for LIHC and further elucidate the mechanisms underlying DEPDC1B-related LIHC, numerous databases, such as Oncomine, Gene Expression Profiling Interactive Analysis (GEPIA), UALCAN, Kaplan-Meier plotter, and The Cancer Genome Atlas (TCGA) were employed to determine the association between the expression of DEPDC1B and prognosis in LIHC patients. Generally, the DEPDC1B mRNA level was highly expressed in LIHC tissues, compared with that in normal tissues (p &lt; 0.01). High DEPDC1B expression was associated with poor overall survival (OS) in LIHC patients, especially in stage II, IV, and grade I, II, III patients (all p &lt; 0.05). The univariate and multivariate Cox regression analysis showed that DEPDC1B was an independent risk factor for OS among LIHC patients (HR = 1.3, 95% CI: 1.08–1.6, p = 0.007). In addition, the protein expression of DEPDC1B was validated using Human Protein Atlas database. Furthermore, the expression of DEPDC1B was confirmed by quantitative real-time polymerase chain reaction (qRT-PCR) assay using five pairs of matched LIHC tissues and their adjacent noncancerous tissues. The KEGG pathway analysis indicated that high expression of DEPDC1B may be associated with several signaling pathways, such as MAPK signaling, the regulation of actin cytoskeleton, p53 signaling, and the Wnt signaling pathways. Furthermore, high DEPDC1B expression may be significantly associated with various cancers. Conclusively, DEPDC1B may be an independent risk factor for OS among LIHC cancer patients and may be used as an early diagnostic marker in patients with LIHC.

TMED3 promotes the progression and development of lung squamous cell carcinoma by regulating EZR

Lung squamous cell carcinoma (LUSC) has a poor clinical prognosis and lacks effective targeted therapy. The transmembrane emp24 trafficking protein 3 (TMED3) belongs to the TMED family, which is responsible for the transport of intracellular proteins. This study was to explore the clinicopathological significance and biological effects of TMED3 in LUSC. Expression of TMED3 in LUSC was detected by immunohistochemical (IHC). The loss-of-function assays were used to investigate the effects of TMED3 on proliferation, apoptosis, cell cycle, and migration of LUSC cells. The influence of TMED3 knockdown on tumor growth in vivo was evaluated by mice xenograft models. In addition, the downstream target of TMED3 was recognized by RNA sequencing and Ingenuity Pathway Analysis (IPA). Moreover, TMED3 was upregulated in LUSC tissue, which was positively correlated with pathological grade. TMED3 knockdown was involved in the regulation of LUSC cell function, such as inhibition of proliferation, reduction of colony formation, induction of apoptosis, and reduction of migration. TMED3 knockdown induced abnormalities in apoptosis-related proteins in LUSC cells. In addition, the inhibition of cell migration by TMED3 knockdown was achieved by regulating EMT. Mechanically, EZR was considered as a potential target for TMED3 to regulate the progress of LUSC. Inhibition of EZR can inhibit the progression of LUSC, and even reduce the promoting effects of TMED3 overexpression on LUSC. In conclusion, TMED3 promoted the progression and development of LUSC by EZR, which may be a novel therapeutic target for LUSC.

Identification of subgroups along the glycolysis-cholesterol synthesis axis and the development of an associated prognostic risk model

BACKGROUND

Skin cutaneous melanoma (SKCM) is one of the most highly prevalent and complicated malignancies. Glycolysis and cholesterogenesis pathways both play important roles in cancer metabolic adaptations. The main aims of this study are to subtype SKCM based on glycolytic and cholesterogenic genes and to build a clinical outcome predictive algorithm based on the subtypes.

METHODS

A dataset with 471 SKCM specimens was downloaded from The Cancer Genome Atlas (TCGA) database. We extracted and clustered genes from the Molecular Signatures Database v7.2 and acquired co-expressed glycolytic and cholesterogenic genes. We then subtyped the SKCM samples and validated the efficacy of subtypes with respect to simple nucleotide variations (SNVs), copy number variation (CNV), patients' survival statuses, tumor microenvironment, and proliferation scores. We also constructed a risk score model based on metabolic subclassification and verified the model using validating datasets. Finally, we explored potential drugs for high-risk SKCM patients.

RESULTS

SKCM patients were divided into four subtype groups: glycolytic, cholesterogenic, mixed, and quiescent subgroups. The glycolytic subtype had the worst prognosis and MGAM SNV extent. Compared with the cholesterogenic subgroup, the glycolytic subgroup had higher rates of DDR2 and TPR CNV and higher proliferation scores and MK167 expression levels, but a lower tumor purity proportion. We constructed a forty-four-gene predictive signature and identified MST-321, SB-743921, Neuronal Differentiation Inducer III, romidepsin, vindesine, and YM-155 as high-sensitive drugs for high-risk SKCM patients.

CONCLUSIONS

Subtyping SKCM patients via glycolytic and cholesterogenic genes was effective, and patients in the glycolytic-gene enriched group were found to have the worst outcome. A robust prognostic algorithm was developed to enhance clinical decisions in relation to drug administration.

DEPDC1B regulates the progression of human chordoma through UBE2T-mediated ubiquitination of BIRC5

Chordoma is a rare bone malignancy with a high rate of local recurrence and distant metastasis. Although DEP domain-containing protein 1B (DEPDC1B) is implicated in a variety of malignancies, its relationship with chordoma is unclear. In this study, the biological role and molecular mechanism of DEPDC1B in chordoma were explored. The function of DEPDC1B in chordoma cells was clarified through loss-of-function assays in vitro and in vivo. Furthermore, molecular mechanism of DEPDC1B in chordoma cells was recognized by RNA sequencing and Co-Immunoprecipitation (Co-IP) assay. The malignant behaviors of DEPDC1B knockdown chordoma cells was significantly inhibited, which was characterized by reduced proliferation, enhanced apoptosis, and hindered migration. Consistently, decreased expression of DEPDC1B suppressed tumor growth in xenograft mice. Mechanically, DEPDC1B affected the ubiquitination of baculoviral inhibitor of apoptosis repeat-containing 5 (BIRC5) through ubiquitin-conjugating enzyme E2T (UBE2T). Simultaneous downregulation of BIRC5 and DEPDC1B may exacerbate the inhibitory effects of chordoma. Moreover, BIRC5 overexpression reduced the inhibitory effects of DEPDC1B knockdown in chordoma cells. In conclusion, DEPDC1B regulates the progression of human chordoma through UBE2T-mediated ubiquitination of BIRC5, suggesting that it may be a promising candidate target with potential therapeutic value.

Overexpressed DEPDC1B contributes to the progression of hepatocellular carcinoma by CDK1

BACKGROUND

Hepatocellular carcinoma (HCC) is the main type of primary liver cancer and shows a heavy burden worldwide. Its recurrence and mortality rate are still uncontrolled by the usage of present treatments. More attention has been focused on exploring specific genes that play important roles in HCC procession, and the function of DEP domain containing 1B (DEPDC1B) in HCC has not been researched.

METHODS

Immunohistochemical staining was used to detect the expression level of DEPDC1B in tumor tissues and adjacent normal tissues. After DEPDC1B and CDK1 knockdown in cell lines HEP3B2.1-7 and SK-HEP-1, MTT assay and colony formation assay was used to detect cell growth, flow cytometry assay was used to investigate cell apoptosis and cell cycle, wound-healing assay and Transwell assay were used to examine the tumor cell migration. Moreover, a xenograft model was constructed to research functions of DEPDC1B in tumor growth in vivo.

RESULTS

The results show that DEPDC1B knockdown inhibit the progression of HCC, through inhibiting cell proliferation, migration, colony formation, leading to G2 phase arrest, and promoting cell apoptosis in vitro, and CDK1 was selected for further mechanic research according to the results of Human GeneChip prime view. The results of recovery experiment displayed that the functions of DEPDC1B on HCC progression were mediated by CDK1. DEPDC1B knockdown can also inhibit tumor growth in vivo.

CONCLUSIONS

The study confirmed that DEPDC1B knockdown restrains the tumor growth in vitro and vivo, and it can interact with CDK1 and rescued by CDK1. The study suggested that DEPDC1B was as a potential therapeutic target involved in HCC growth and progression.

Expression of DEP Domain-Containing 1B in Canine Lymphoma and Other Types of Canine Tumours

Canine lymphoma is the most common haematological malignancy in dogs and is typically treated with multidrug chemotherapy. Most cases are at risk of relapse after several courses of chemotherapy and the oncogenic mechanism remains unknown. This study was aimed at identifying genes expressed in canine lymphoma by cDNA microarray. We found elevated expression of Dishevelled, EGL-10 and pleckstrin (DEP) domain-containing 1B (DEPDC1B) in canine lymphoma cells compared with cells and tissues from healthy dogs. Canine DEPDC1B protein was detected in 13 of 41 lymphoma specimens by immunohistochemistry, but was not detected in lymph nodes from normal dogs. Immunoreactive DEPDC1B protein was also detected in several other types of canine tumour. This is the first report documenting the association of DEPDC1B with canine cancer and the results suggest that DEPDC1B might serve as a potential marker or therapeutic target for canine malignancies.

A Novel Apoptosis-Related Gene Signature Predicts Biochemical Recurrence of Localized Prostate Cancer After Radical Prostatectomy

Background: Nowadays, predictions of biochemical recurrence (BCR) in localized prostate cancer (PCa) patients after radical prostatectomy (RP) are mainly based on clinical parameters with a low predictive accuracy. Given the critical role of apoptosis in PCa occurrence and progression, we aimed to establish a novel predictive model based on apoptosis-related gene signature and clinicopathological parameters that can improve risk stratification for BCR and assist in clinical decision-making. Methods: Expression data and corresponding clinical information were obtained from four public cohorts, one from The Cancer Genome Atlas (TCGA) dataset and three from the Gene Expression Omnibus (GEO) dataset. Weighted gene co-expression network analysis (WGCNA) was performed to identify candidate modules closely correlated to BCR, and univariate and multivariate Cox regression analyses were utilized to build the gene signature. Time-dependent receiver operating curve (ROC) and Kaplan-Meier (KM) survival analysis were used to assess the prognostic value. Finally, we analyzed the expression of genes in the signature and validated the results using quantitative real-time PCR (qRT-PCR). Results: The novel gene signature we established exhibited a high prognostic value and was able to act as an independent risk factor for BCR [Training set: P < 0.001, hazard ratio (HR) = 7.826; Validation set I: P = 0.006, HR = 2.655; Validation set II: P = 0.003, HR = 4.175; Validation set III: P < 0.001, HR = 3.008]. Nomogram based on the gene signature and clinical parameters was capable of distinguishing high-risk BCR patients. Additionally, functional enrichment analysis showed several enriched pathways and biological processes, which might help reveal the underlying mechanism. The expression results of qRT-PCR were consistent with TCGA results. Conclusion: The apoptosis-related gene signature could serve as a powerful predictor and risk factor for BCR in localized PCa patients after RP.

DEPDC1B is a tumor promotor in development of bladder cancer through targeting SHC1

Bladder cancer is one of the most commonly diagnosed malignant tumors in the urinary system and causes a massive cancer-related death. DEPDC1B is a DEP domain-containing protein that has been found to be associated with a variety of human cancers. This study aimed to explore the role and mechanism of DEPDC1B in the development of bladder cancer. The analysis of clinical specimens revealed the upregulated expression of DEPDC1B in bladder cancer, which was positively related to tumor grade. In vitro and in vivo studies showed that DEPDC1B knockdown could inhibit the growth of bladder cancer cells or xenografts in mice. The suppression of bladder cancer by DEPDC1B was executed through inhibiting cell proliferation, cell migration, and promoting cell apoptosis. Moreover, a mechanistic study found that SHC1 may be an important route through which DEPDC1B regulates the development of bladder cancer. Knockdown of SHC1 in DEPDC1B-overexpressed cancer cells could abolish the promotion effects induced by DEPDC1B. In conclusion, DEPDC1B was identified as a key regulator in the development of bladder cancer, which may be used as a potential therapeutic target in the treatment of bladder cancer.

Fine Needle Aspiration Cytology (FNAC) for Chinese Patients With Acral and Cutaneous Melanoma: Accuracy and Safety Analysis From a Single Institution

This study aimed to investigate the accuracy and safety of fine-needle aspiration cytology (FNAC) in Chinese patients with acral and cutaneous melanoma, and also to evaluate the influencing factors and their impact on prognosis. Data of 128 patients with stage 0-III acral and cutaneous melanoma treated in Fudan University Shanghai Cancer Center from 2009 to 2016 were collected from a prospective database. Further, 128 patients who did not undergo FNAC but had similar parameters were recruited as the matched group. Clinical features, FNAC status, and recurrence or metastasis status of patients were analyzed for overall survival (OS), melanoma-specific survival (MSS), recurrence-free survival (RFS), and metastasis-free survival (MFS). Of the 128 patients with FNAC, 5.5% (7/128) had a negative cytological diagnosis, 12.2% (5/41) had primary lesions, and 2.3% (2/87) had lesions in lymph nodes. Tumor thickness, status of ulceration, and subtype were not associated with accuracy for both primary and lymph node FNAC. With a median follow-up of 40 months in all patients, 55 had melanoma-specific death; the median OS and MSS were 95 months and 104 months, respectively. Patients with FNAC had significantly worse OS. Tumor progression occurred in 130 patients. The survival analysis revealed differences in OS and disease-free survival between the two groups. FNAC impacted patients' RFS and MFS; the difference in survival curves of RFS and MFS was also statistically significant. FNAC on primary or superficial lymphatic lesions was a good diagnostic tool for Chinese patients with acral and cutaneous melanoma, but it adversely impacted prognosis.

DEPDC1B promotes migration and invasion in pancreatic ductal adenocarcinoma by activating the Akt/GSK3β/Snail pathway

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal disease, which frequently presents with distant metastasis. Further understanding of the molecular mechanism of PDAC is helpful to uncover novel and effective therapeutic strategies. DEP domain containing 1B (DEPDC1B) is known to play a role in the carcinogenesis and metastasis of several common types of cancer; however, its biological function and molecular mechanism in PDAC progression remain unclear. In the present study, the expression levels of DEPDC1B were detected in 79 pairs of PDAC and adjacent non-cancerous tissues. Patients with PDAC that exhibited higher DEPDC1B expression levels, were shown to have a poorer prognosis. Functional studies showed that knocking down DEPDC1B inhibited PDAC cell migration and invasion, while overexpressing DEPDC1B promoted these processes. Western blotting analysis and immunofluorescence demonstrated that DEPDC1B overexpression induced the epithelial-to-mesenchymal transition (EMT). Further mechanistic studies revealed that DEPDC1B was able to activate the Akt/glycogen synthase kinase-3β (GSK3β)/Snail signaling pathway. In conclusion, the results of the present study showed that DEPDC1B may serve as an oncogene that contributes to PDAC cell migration and invasion by inducing EMT via Akt/GSK3β/Snail pathway activation.

Establishment of rat anti-canine DEP domain containing 1B (DEPDC1B) monoclonal antibodies

DEP domain-containing 1B (DEPDC1B) is involved in the regulation of cell de-adhesion and actin cytoskeleton activity during the G2/M transition of the cell cycle, and its overexpression has been proven to be associated with cancer progression in several human cancers. Canine DEPDC1B was identified as a gene that was overexpressed in canine lymphoma tissues in our previous study. However, in dogs, the protein expression of DEPDC1B remains to be determined due to the lack of a specific monoclonal antibody. Here, we developed rat monoclonal antibodies against canine DEPDC1B and characterized their applicability for immunodetection assays. Our findings demonstrated that these antibodies are functional and can be important tools to investigate the precise role of DEPDC1B in canine tumors.

DEP Domain-Containing Protein 1B (DEPDC1B) Promotes Migration and Invasion in Pancreatic Cancer Through the Rac1/PAK1-LIMK1-Cofilin1 Signaling Pathway

Background

With increasing incidence, pancreatic cancer (PC) is one of the most common digestive tract tumors. However, the prognosis of PC is particularly dismal due to the highly invasive and metastatic behavior of this deadly disease. DEP domain-containing protein 1B (DEPDC1B), which is overexpressed in multiple tumors, such as breast cancer, oral cancer and non-small cell lung cancer, plays a significant role in cell movement, cell cycle and cytoskeleton reorganization. However, the function of DEPDC1B in PC remains poorly understood.

Methods

The function of DEPDC1B in the migration and invasion of PC was evaluated by wound healing and Transwell assays in vitro and PC-derived liver metastasis models in vivo. The molecular mechanisms of DEPDC1B were investigated through cell line establishment, Western blotting, qRT-PCR, immunoprecipitation, histological examination and immunohistochemistry analysis.

Results

DEPDC1B was overexpressed in PC cell lines. DEPDC1B regulated cell migration and invasion. DEPDC1B regulated the Rac1/PAK1-LIMK1-cofilin1 signaling pathway by interacting with Rac1. Rac1 inhibition suppressed DEPDC1B-induced migration and invasion in PC in vitro and DEPDC1B-induced liver metastasis in vivo.

Conclusion

DEPDC1B promoted cell migration and invasion by activating the Rac1/PAK1-LIMK1-cofilin1 signaling pathway, thus providing a potential therapeutic target against PC.

DEPDC1B is a key regulator of myoblast proliferation in mouse and man

OBJECTIVES

DISHEVELLED, EGL-10, PLECKSTRIN (DEP) domain-containing 1B (DEPDC1B) promotes dismantling of focal adhesions and coordinates detachment events during cell cycle progression. DEPDC1B is overexpressed in several cancers with expression inversely correlated with patient survival. Here, we analysed the role of DEPDC1B in the regulation of murine and human skeletal myogenesis.

MATERIALS AND METHODS

Expression dynamics of DEPDC1B were examined in murine and human myoblasts and rhabdomyosarcoma cells in vitro by RT-qPCR and/or immunolabelling. DEPDC1B function was mainly tested via siRNA-mediated gene knockdown.

RESULTS

DEPDC1B was expressed in proliferating murine and human myoblasts, with expression then decreasing markedly during myogenic differentiation. SiRNA-mediated knockdown of DEPDC1B reduced myoblast proliferation and induced entry into myogenic differentiation, with deregulation of key cell cycle regulators (cyclins, CDK, CDKi). DEPDC1B and β-catenin co-knockdown was unable to rescue proliferation in myoblasts, suggesting that DEPDC1B functions independently of canonical WNT signalling during myogenesis. DEPDC1B can also suppress RHOA activity in some cell types, but DEPDC1B and RHOA co-knockdown actually had an additive effect by both further reducing proliferation and enhancing myogenic differentiation. DEPDC1B was expressed in human Rh30 rhabdomyosarcoma cells, where DEPDC1B or RHOA knockdown promoted myogenic differentiation, but without influencing proliferation.

CONCLUSION

DEPDC1B plays a central role in myoblasts by driving proliferation and preventing precocious myogenic differentiation during skeletal myogenesis in both mouse and human.

XTP8 promotes hepatocellular carcinoma growth by forming a positive feedback loop with FOXM1 oncogene

Hepatocellular carcinoma (HCC) is one of the most common cancer in the world and the main cause of cancer death. Chronic hepatitis B virus (HBV) infection is the major cause of HCC. HBx, as a transactivator, plays an important role in the occurrence and development process of HCC leading by HBV infection. XTP8, related to HBx, however, there are no studies on the function of XTP8 in HCC. In our research, we demonstrated that XTP8 was significantly up-regulated in HCC tissues compared with non-cancerous tissues in Oncomine, TCGA and GEO database. Moreover, Kaplan-Meier Plotter analysis indicated that patients with higher XTP8 expression had significantly lower overall survival. Our immunohistochemical results suggested that XTP8 protein expression in HCC tissues was dramatically higher compared with control normal tissues. In vivo xenograft experiments on nude mice, the overexpression of XTP8 promoted the tumorigenic ability of HepG2 cells. In HepG2 and Huh7 cells, XTP8 upregulated FOXM1 expression to promote cell proliferation and inhibited cell apoptosis. FOXM1 knockdown reduced promoter activity of XTP8 to downregulate XTP8 expression. Thiostrepton, an inhibitor of FOXM1, decreased XTP8 expression. Therefore, our study demonstrates that XTP8 is a valuable prognostic predictor for HCC and there is a novel positive regulatory feedback loop between XTP8 and FOXM1 promoting the development of HCC.