Coronin 3 promotes gastric cancer metastasis via the up-regulation of MMP-9 and cathepsin K

CORO1C Regulates the Malignant Biological Behavior of Ovarian Cancer Cells and Modulates the mRNA Expression Profile through the PI3K/AKT Signaling Pathway

Ovarian cancer (OC) is a frequently occurring gynecological tumor, and its global incidence has recently increased. Coronin-like actin-binding protein 1C (CORO1C) is known to activate the phosphoinositide 3-kinase (PI3K)-protein kinase B (AKT) pathway and promote tumor progression. However, its role in OC remains unclear. This study investigated the role of CORO1C in OC malignancy. In this study, quantitative real-time polymerase chain reaction (qRT-PCR) was used to examine AKT and CORO1C mRNA expression in clinical OC tissues and cells. Immunohistochemical analysis and western blotting were used to examine protein expression in OC tissues and cells, respectively. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), scratch wound-healing, and Transwell assays were performed to examine cell proliferation and migration. RNA-Seq was used to validate the relationship between AKT and CORO1C expression. The results showed that CORO1C was highly expressed in clinical OC tissues and SKOV3 cells, correlating with the International Federation of Gynecology and Obstetrics (FIGO) stage. Furthermore, CORO1C knockout inhibited the proliferation, migration, and invasion of SKOV3 cells; altered the gene expression patterns in these cells; and was closely associated with the PI3K/AKT pathway. Western blotting confirmed that CORO1C knockout reduced the levels of phosphorylated PI3K and AKT. Additionally, CORO1C knockout increased phosphatase and tensin homologs deleted on chromosome 10 (PTEN) protein expression, whereas CORO1C overexpression decreased it. In conclusion, this study demonstrated that high CORO1C levels in OC are associated with greater metastasis and worse prognosis. CORO1C negatively regulates PTEN expression, activates the PI3K/AKT pathway, and promotes OC cell malignancy In patients with OC, CORO1C may function as an effective therapeutic and predictive biomarker.

Synergizing autophagic cell death and oxaliplatin-induced immunogenic death by a self-delivery micelle for enhanced tumor immunotherapy

Chemotherapy has become an emerging strategy to activate cytotoxic T cell responses by inducing immunogenic cell death (ICD), but the level of antitumor immunity induced by chemotherapeutic agents, such as oxaliplatin (OXA), is limited due to inadequate tumor antigen presentation and T cell activation. Inducing autophagic cell death (ACD) promotes the release of tumor antigen and the recruitment of dendritic cells, therefore strengthening antitumor immune responses. Here we simultaneously activate ICD and ACD with tumor targeting micelle to achieve enhanced antitumor chemo-immunotherapy. A self-delivery micelle is formulated by conjugating OXA prodrug with tocopherol succinate (TOS) as a hydrophobic segment and further encapsulates autophagy activator SMER28 to afford TOPR/SMER28, which specifically targets αvβ3 on tumor cells with c(RGDfK). Upon cellular internalization, OXA is released from the prodrug in response to the high concentration of reduced glutathione (GSH) in tumor cells, triggering ICD and releasing associated molecular patterns (DAMPs) signaling molecules to stimulate immunity. Meanwhile, SMER28 over-activates autophagy to induce autophagic cell death, which further leads to the maturation of dendritic cells and ultimately activates anti-tumor immune response. In the 4T1 tumor-bearing mice, the combination of OXA and SMER28 effectively inhibits tumor growth and activates antitumor immune responses. The tumor targeted micelle releases OXA and SMER28 in an on-demand profile and strengthens tumor chemo-immunotherapy by synergizing ICD and ACD, providing an alternative for antitumor immunotherapy. STATEMENT OF SIGNIFICANCE: Chemotherapy induces immunogenic cell death (ICD) to activate anti-tumor immunity. However, the efficacy is limited by low levels of antigen presentation and T cell activation. To strengthen the antitumor immune responses induced by ICD, we first combine autophagic cell death (ACD) with ICD by formulating a glutathione-responsive oxaliplatin prodrug micelle co-encapsulating the autophagy activator SMER28. The activated autophagic level by SMER28 enhances the release of antigen and the recruitment of APCs, and ultimately bolsters T cell-mediated antitumor immune responses. We provide a potential strategy to amplify antitumor immune effects by combining autophagy activation with chemotherapy.

Airway epithelial overexpressed cathepsin K induces airway remodelling through epithelial-mesenchymal trophic unit activation in asthma

BACKGROUND AND PURPOSE

Airway epithelial cells (AECs) regulate the activation of epithelial-mesenchymal trophic units (EMTUs) during airway remodelling through secretion of signalling mediators. However, the major trigger and the intrinsic pathogenesis of airway remodelling is still obscure.

EXPERIMENTAL APPROACH

The differing expressed genes in airway epithelia related to airway remodelling were screened and verified by RNA-sequencing and signalling pathway analysis. Then, the effects of increased cathepsin K (CTSK) in airway epithelia on airway remodelling and EMTU activation were identified both in vitro and in vivo, and the molecular mechanism was elucidated in the EMTU model. The potential of CTSK as an an effective biomarker of airway remodelling was analysed in an asthma cohort of differing severity. Finally, an inhibitor of CTSK was administered for potential therapeutic intervention for airway remodelling in asthma.

KEY RESULTS

The expression of CTSK in airway epithelia increased significantly along with the development of airway remodelling in a house dust mite (HDM)-stressed asthma model. Increased secretion of CTSK from airway epithelia induced the activation of EMTUs by activation of the PAR2-mediated pathway. Blockade of CTSK inhibited EMTU activation and alleviated airway remodelling as an effective intervention target of airway remodelling.

CONCLUSION AND IMPLICATIONS

Increased expression of CTSK in airway epithelia is involved in the development of airway remodelling in asthma through EMTU activation, mediated partly through the PAR2-mediated signalling pathway. CTSK is a potential biomarker for airway remodelling, and may also be a useful intervention target for airway remodelling in asthma patients.

Prediction and therapeutic targeting of the tumor microenvironment-associated gene CTSK in gastric cancer

BACKGROUND

Cathepsin-K (CTSK) is overexpressed in Gastric cancer (GC) and the mechanism of its overexpression in GC is still unclear. The present work found CTSK as a potential predictive biomarker and immunotherapeutic target for GC based on the tumor microenvironment (TME).

METHODS

From public databases, gene expression profiles and clinical data of GC were downloaded to analyze the distribution of stromal and immune cells and tumor abundance in TME. Differentially expressed genes (DEGs) associated with TME were obtained by differential analysis, followed by cross-screening to obtain CTSK as a gene associated with TME. Next, a series of methods and tools were employed to explore the relationships between clinicopathological features of GC and CTSK expression as well as prognosis, tumor immune microenvironment, immune checkpoints and drug sensitivity. And GSEA was used to investigate the potential role of CTSK in the tumor microenvironment of GC.

RESULTS

From the dataset, we obtained a total of 656 DEGs associated with TME and the stromal component of TME was found to be closely involved in GC prognosis. CTSK was cross-screened as the key gene associated with TME by the PPI network and univariate Cox regression analysis. Pan-cancer analysis revealed significant high expression of CTSK in a variety of cancers. Subsequently, we hypothesized that high-expressed CTSK was closely correlated with poor prognosis and lymph node metastasis of tumors, and that CTSK, a GC TME-related gene, was largely involved in a range of biological behaviors of tumors, with a significant correlation between several immune cells.

CONCLUSION

CTSK was validated as a potential prognostic biomarker related to TME of GC and could be a promising next-generation immunotherapeutic target for GC.

Molecular mechanism and potential therapeutic targets of liver metastasis from gastric cancer

Gastric cancer (GC) is characterized by high invasion and poor prognosis. The occurrence of liver metastasis seriously affects advanced GC prognosis. In recent years, great progress has been made in the field of GC liver metastasis. The abnormal expression of related genes leads to the occurrence of GC liver metastasis through metastasis cascades. The changes in the liver microenvironment provide a pre-metastasis condition for GC cells to colonize and grow. The development of several potential therapeutic targets might provide new therapeutic strategies for its treatment. Therefore, we reviewed the regulatory mechanism of abnormal genes mediating liver metastasis, the effect of liver resident cells on liver metastasis, and potential therapeutic targets, hoping to provide a novel therapeutic option to improve the quality of life and prognosis of GC patients with liver metastasis.

Cathepsin K: A Versatile Potential Biomarker and Therapeutic Target for Various Cancers

Cancer, a common malignant disease, is one of the predominant causes of diseases that lead to death. Additionally, cancer is often detected in advanced stages and cannot be radically cured. Consequently, there is an urgent need for reliable and easily detectable markers to identify and monitor cancer onset and progression as early as possible. Our aim was to systematically review the relevant roles of cathepsin K (CTSK) in various possible cancers in existing studies. CTSK, a well-known key enzyme in the bone resorption process and most studied for its roles in the effective degradation of the bone extracellular matrix, is expressed in various organs. Nowadays, CTSK has been involved in various cancers such as prostate cancer, breast cancer, bone cancer, renal carcinoma, lung cancer and other cancers. In addition, CTSK can promote tumor cells proliferation, invasion and migration, and its mechanism may be related to RANK/RANKL, TGF-β, mTOR and the Wnt/β-catenin signaling pathway. Clinically, some progress has been made with the use of cathepsin K inhibitors in the treatment of certain cancers. This paper reviewed our current understanding of the possible roles of CTSK in various cancers and discussed its potential as a biomarker and/or novel molecular target for various cancers.

Coronin1C Is a GDP-Specific Rab44 Effector That Controls Osteoclast Formation by Regulating Cell Motility in Macrophages

Osteoclasts are multinucleated bone-resorbing cells that are formed by the fusion of macrophages. Recently, we identified Rab44, a large Rab GTPase, as an upregulated gene during osteoclast differentiation that negatively regulates osteoclast differentiation. However, the molecular mechanisms by which Rab44 negatively regulates osteoclast differentiation remain unknown. Here, we found that the GDP form of Rab44 interacted with the actin-binding protein, Coronin1C, in murine macrophages. Immunoprecipitation experiments revealed that the interaction of Rab44 and Coronin1C occurred in wild-type and a dominant-negative (DN) mutant of Rab44, but not in a constitutively active (CA) mutant of Rab44. Consistent with these findings, the expression of the CA mutant inhibited osteoclast differentiation, whereas that of the DN mutant enhanced this differentiation. Using a phase-contrast microscope, Coronin1C-knockdown osteoclasts apparently impaired multinuclear formation. Moreover, Coronin1C knockdown impaired the migration and chemotaxis of RAW-D macrophages. An in vivo experimental system demonstrated that Coronin1C knockdown suppresses osteoclastogenesis. Therefore, the decreased cell formation and fusion of Coronin1C-depleted osteoclasts might be due to the decreased migration of Coronin1C-knockdown macrophages. These results indicate that Coronin1C is a GDP-specific Rab44 effector that controls osteoclast formation by regulating cell motility in macrophages.

Dual ATP/reduction-responsive polyplex to achieve the co-delivery of doxorubicin and miR-23b for the cancer treatment

Combination therapy based on the co-delivery of therapeutic genes and anti-cancer drugs has emerged as a promising approach in the cancer treatment, and stimuli-responsive delivery systems could further improve the therapeutic efficacy. Herein, an ATP aptamer and its complementary DNA were used to form Duplex into which doxorubicin (DOX) was loaded to construct DOX-Duplex, and then the lipoic acid-modified oligoethyleneimine (LA-OEI) was employed as a carrier to realize the co-delivery of DOX-Duplex and miR-23b. The ternary nanocomplex LA-OEI/miR-23b/DOX-Duplex showed excellent anti-proliferative effect by inducing the cell apoptosis via mitochondrial signaling pathway and arresting the cell cycle at S phase. Meanwhile, the co-delivery of DOX-Duplex and miR-23b could efficiently inhibit the metastasis of cancer cells by reducing the expression level of MMP-9. The favorable anti-tumor efficacy of ternary nanocomplex was attributed to the rapid drug release in response to intracellular ATP concentration and reduction conditions and the synergistic effect between DOX-Duplex and miR-23b. Thus, ATP aptamer and reduction-responsive polymer provided a convenient platform to construct dual stimuli-responsive systems for the co-delivery of gene and drug in the cancer treatment.

CORO1C is Associated With Poor Prognosis and Promotes Metastasis Through PI3K/AKT Pathway in Colorectal Cancer

Trophoblast cell surface protein 2 (Trop2) is one of the cancer-related proteins that plays a vital role in biological aggressiveness and poor prognosis of colorectal cancer (CRC). The study of the Trop2 related network is helpful for us to understand the mechanism of tumorigenesis. However, the effects of the related proteins interacting with Trop2 in CRC remain unclear. Here, we found that coronin-like actin-binding protein 1C (CORO1C) could interact with Trop2 and the expression of CORO1C in CRC tissues was higher than that in paracarcinoma tissues. The expression of CORO1C was associated with histological type, lymph node metastasis, distant metastasis, AJCC stage, venous invasion, and perineural invasion. The correlation between CORO1C expression and clinical characteristics was analyzed demonstrating that high CORO1C expression in CRC patients were associated with poor prognosis. Furthermore, CORO1C knockdown could decrease the cell proliferation, colony formation, migration and invasion in vitro and tumor growth in vivo. The underlying mechanisms were predicted by bioinformatics analysis and verified by Western blotting. We found that PI3K/AKT signaling pathway was significantly inhibited by CORO1C knockdown and the tuomr-promoting role of CORO1C was leastwise partly mediated by PI3K/AKT signaling pathway. Thus, CORO1C may be a valuable prognostic biomarker and drug target in CRC patients.

L-Plastin Promotes Gastric Cancer Growth and Metastasis in a Helicobacter pylori cagA-ERK-SP1-Dependent Manner

Actin cytoskeleton dynamic rearrangement is required for tumor cell metastasis and is a key characteristic of Helicobacter pylori (H. pylori)-infected host cells. Actin cytoskeleton modulation is coordinated by multiple actin-binding proteins (ABP). Through Kyoto encyclopedia of gene and genomes database, GEPIA website, and real-time PCR data, we found that H. pylori infection significantly induced L-plastin, a key ABP, in gastric cancer cells. We further explored the regulation and function of L-plastin in H. pylori-associated gastric cancer and found that, mechanistically, H. pylori infection induced gastric cancer cells to express L-plastin via cagA-activated ERK signaling pathway to mediate SP1 binding to L-plastin promoter. Moreover, this increased L-plastin promoted gastric cancer cell proliferation and migration in vitro and facilitated the growth and metastasis of gastric cancer in vivo. Finally, we detected the expression pattern of L-plastin in gastric cancer tissues, and found that L-plastin was increased in gastric cancer tissues and that this increase of L-plastin positively correlated with cagA + H. pylori infection status. Overall, our results elucidate a novel mechanism of L-plastin expression induced by H. pylori, and a new function of L-plastin-facilitated growth and metastasis of gastric cancer, and thereby implicating L-plastin as a potential therapeutic target against gastric cancer. IMPLICATIONS: Our results elucidate a novel mechanism of L-plastin expression induced by H. pylori in gastric cancer, and a new function of L-plastin-facilitated gastric cancer growth and metastasis, implicating L-plastin as a potential therapeutic target against gastric cancer.

Cancer stem cell marker DCLK1 reprograms small extracellular vesicles toward migratory phenotype in gastric cancer cells

Doublecortin-like kinase 1 (DCLK1) is a putative cancer stem cell marker, a promising diagnostic and prognostic maker for malignant tumors and a proposed driver gene for gastric cancer (GC). DCLK1 overexpression in a majority of solid cancers correlates with lymph node metastases, advanced disease and overall poor-prognosis. In cancer cells, DCLK1 expression has been shown to promote epithelial-to-mesenchymal transition (EMT), driving disruption of cell-cell adhesion, cell migration and invasion. Here, we report that DCLK1 influences small extracellular vesicle (sEV/exosome) biogenesis in a kinase-dependent manner. sEVs isolated from DCLK1 overexpressing human GC cell line MKN1 (MKN1^OE -sEVs), promote the migration of parental (non-transfected) MKN1 cells (MKN1^PAR ). Quantitative proteome analysis of MKN1^OE -sEVs revealed enrichment in migratory and adhesion regulators (STRAP, CORO1B, BCAM, COL3A, CCN1) in comparison to MKN1^PAR -sEVs. Moreover, using DCLK1-IN-1, a specific small molecule inhibitor of DCLK1, we reversed the increase in sEV size and concentration in contrast to other EV subtypes, as well as kinase-dependent cargo selection of proteins involved in EV biogenesis (KTN1, CHMP1A, MYO1G) and migration and adhesion processes (STRAP, CCN1). Our findings highlight a specific role of DCLK1-kinase dependent cargo selection for sEVs and shed new light on its role as a regulator of signaling in gastric tumorigenesis.

CORO6 Promotes Cell Growth and Invasion of Clear Cell Renal Cell Carcinoma via Activation of WNT Signaling

Renal cell carcinoma (RCC) constitutes the most lethal type of genitourinary cancer. Understanding of RCC tumor biology helps to identify novel targets and develop directed treatments for patients with this type of cancer. Analysis from both The Cancer Genome Atlas Kidney Renal Clear Cell Carcinoma dataset and our RCC samples demonstrated that the expression level of CORO6 was significantly higher in RCC patients than in normal kidney tissues, and its level was highly associated with tumor stage and grade. Importantly, CORO6 expression level was an independent predictor of tumor metastasis and overall survival in RCC patients. Our cell line data also confirmed that CORO6 knockdown could suppress RCC cell growth as well as cell migration and invasion. The depletion of CORO6 led to cell cycle arrest at the G0/G1 phase and caused cell apoptosis. Further, mechanistic dissection showed that CORO6 mediated RCC cell growth, and cell invasion relied on WNT signaling. Moreover, the in vivo data suggested that CORO6 knockdown indeed suppressed RCC tumor growth. Overall, our study defines the oncogenic role of CORO6 in RCC progression and provides a rationale for developing CORO6-targeted therapies for improved treatment of RCC patients.

Prognostic values of EDNRB in triple-negative breast cancer

Triple-negative breast cancer (TNBC) has a high degree of malignancy. The endothelin B receptor (EDNRB) serves an important role in the occurrence and development of cancer. The present study aimed to investigate the prognostic value of EDNRB in TNBC. A total of 99 cases of TNBC were collected from the Henan Cancer Hospital database and 159 cases of TNBC were collected from The Cancer Genome Atlas database. A χ² test was used to analyze the association between EDNRB and clinicopathological data. Kaplan-Meier analysis and multivariate Cox regression analysis were used to analyze the association between EDNRB and prognosis, and to establish two models. The discrimination degree of the models was evaluated using time-dependent receiver operating characteristic curves and concordance index (C-index), whereas the accuracy and net benefit of the models were evaluated using integrated discriminant improvement (IDI) and decision curves. EDNRB expression was low in TNBC samples (P<0.01). Age (P=0.01), tumor size (P=0.04) and N stage (P=0.01) were associated with EDNRB expression. EDNRB expression was positively associated with stromal score (P<0.01), but not immune score. High expression levels of EDNRB indicated favorable disease-free survival time (hazard ratio, 0.38; 95% CI, 0.15–0.98; P=0.04). The integrated area under the curve and C-index of the new model were increased compared with the old model following the addition of EDNRB expression as a parameter. The IDI values for prediction of the 3- and 5-year survival rates were 0.04 (P=0.02) and 0.05 (P=0.01), respectively. The results of decision curve analysis showed that the new model had higher clinical net benefit than the old model in the range of 3-year survival rate <0.52. In conclusion, EDNRB was associated with a favorable prognosis in patients with TNBC, and may be used as a novel prognostic biomarker.

Coronin 1C inhibits melanoma metastasis through regulation of MT1-MMP-containing extracellular vesicle secretion

Coronin 1C is overexpressed in multiple tumors, leading to the widely held view that this gene drives tumor progression, but this hypothesis has not been rigorously tested in melanoma. Here, we combined a conditional knockout of Coronin 1C with a genetically engineered mouse model of PTEN/BRAF-driven melanoma. Loss of Coronin 1C in this model increases both primary tumor growth rates and distant metastases. Coronin 1C-null cells isolated from this model are more invasive in vitro and produce more metastatic lesions in orthotopic transplants than Coronin 1C-reexpressing cells due to the shedding of extracellular vesicles (EVs) containing MT1-MMP. Interestingly, these vesicles contain melanosome markers suggesting a melanoma-specific mechanism of EV release, regulated by Coronin 1C, that contributes to the high rates of metastasis in melanoma.

Coronin 3 Promotes the Development of Oncogenic Properties in Glioma Through the Wnt/β-Catenin Signaling Pathway

PURPOSE

Evidence indicates that the actin-binding protein Coronin 3, which is aberrantly expressed in various cancers, is associated with cancer development and progression. However, little is known about the role of Coronin 3 in glioma tumorigenesis. Here, we aimed to explore the biological function and regulatory mechanism of Coronin 3 in glioblastoma (GBM).

MATERIALS AND METHODS

Coronin 3 level in human GBM clinical samples and cell lines was investigated. The shRNA knockdown strategy was used to assess the tumor characteristics of GBM cell lines. The role of β-catenin in Coronin 3-mediated oncogenic phenotypes was evaluated.

RESULTS

Coronin 3 was found to be highly upregulated in glioma cell lines. Furthermore, knockdown of Coronin 3 significantly inhibited the growth of glioma cells both in vivo and in vitro and suppressed the expression of Wnt/β-catenin pathway genes, including β-catenin, Cyclin D1, and c-Myc. Moreover, we demonstrated that Coronin 3 regulates the expression of β-catenin in glioma. Our results revealed that Coronin 3-stimulated tumor growth was β-catenin-dependent.

CONCLUSION

Our study reveals a new molecular mechanism of Coronin 3 in promoting glioma growth and development through regulating the Wnt/β-catenin signaling pathway.

Suppression of long non-coding RNA MALAT1 inhibits survival and metastasis of esophagus cancer cells by sponging miR-1-3p/CORO1C/TPM3 axis

Esophageal cancer (EC) is a malignancy causing lots of mortality worldwide. Long non-coding RNAs (lncRNAs) are involved in the progression of multiple cancer types. The present study aimed to explore the function and associated mechanisms of lncRNA metastasis-associated lung adenocarcinoma transcript1 (MALAT1) in EC development by focusing on its interaction with miR-1-3p. The levels of MALAT1 and miR-1-3p were investigated in clinical EC specimens. Then, the expression of MALAT1 was knocked down in EC cell lines, and the effects of MALAT1 inhibition on the viability, migration, and invasion, and miR-1-3p/Coronin-1C (CORO1C)/Tropomyosin3 (TPM3) axis in EC cells were detected. The interaction between MALAT1 and miR-1-3p in the progression of EC was further determined by suppressing the expression of miR-1-3p in MALAT1 inhibition cells. The results were further verified with EC xenograft mice model. MALAT1 level was downregulated, while miR-1-3p level was upregulated in EC specimens. The inhibition of MALAT1 suppressed the viability, migration, and invasion in EC cell lines. The changes in phenotypes of EC cells were associated with the upregulation of miR-1-3p level and inhibition of CORO1C/TPM3 activity. Furthermore, the results of dual-luciferase assay showed the direct binding of MALAT1 to the seed sequence of miR-1-3p. The suppressed level of miR-1-3p not only induced the activity of CORO1C/TPM3 signaling, but also upregulated MALAT1 expression, indicating the reciprocal regulation between the two factors. The inhibition of MALAT1 also inhibited tumor growth and epithelial-mesenchymal transition (EMT) in mice model, which was reversed by miR-1-3p inhibition. Collectively, MALAT1 was important to the survival and metastasis of EC cells by sponging miR-1-3p.

Could CTSK and COL4A2 be specific biomarkers of poor prognosis for patients with gastric cancer in Asia?-a microarray analysis based on regional population

Background

In the purpose of identifying reliable biomarkers for evaluating prognosis, monitoring recurrence and exploring new therapeutic targets, it is quite necessary to screen for the genetic changes and potential molecular mechanisms of the occurrence and development of gastric cancer (GC) from the aspects of race and region.

Methods

Target datasets were retrieved from Gene Expression Omnibus (GEO) database with "gastric cancer" as the key word, and corresponding data was downloaded. The differentially expressed genes (DEGs) were obtained by using limma R package, and the Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway for DEGs were analyzed in Enirchr database. Protein-protein interaction (PPI) network and molecular module were also constructed through STRING database and Cytoscape software. Survival analyses were completed for DEGs in GEO and Kaplan-Meier plotter database via cross validation. Finally, the correlation between gene expression and the infiltration cell levels in tumor microenvironment (TME) was explored based on the tumor immune estimation resource (TIMER) database.

Results

Five GC-related microarray datasets were selected and used for differential analysis, and 222 DEGs were identified. GO analyses of DEGs were mainly involved in cell metabolism and the formation of extracellular matrix (ECM). The top enriched pathways of DEGs were protein digestion and absorption, ECM-receptor interaction, focal adhesion (FA), PI3K-Akt signaling pathway. Survival analyses of DEGs revealed that the expression levels of CTSK and COL4A2 were significantly associated with poor prognosis of GC patients in Asian. Specifically, the high expression of CTSK had a closely related to the infiltration level of inflammatory cell in TME.

Conclusions

CTSK and COL4A2 could play a critical role in the pathogenesis of GC and act as the promising prognostic biomarkers. CTSK could induce the formation of immunosuppressive TME and promote the immune escape of GC cells.

MiR-206 may suppress non-small lung cancer metastasis by targeting CORO1C

Object

Non-small lung cancer (NSCLC), with a poor 5-year survival rate (16%), is the major type of lung cancer. Metastasis has been identified as the main factor that leads to NSCLC therapy failure. MiR-206 is a metastasis suppressor in many cancers, including colorectal cancer, renal cell carcinoma and breast cancer. However, the role of miR-206 in NSCLC metastasis and the underlying mechanism are still obscure.

Methods

Quantitative reverse-transcription PCR (q-RT-PCR) assay was used to detect miR-206 mRNA of NSCLC tissues and lung cancer lines. The MTT assay, scratch wound healing assay, transwell migration assay and transwell invasion assay were conducted to illuminate the effect of miR-206 on A549 cells’ proliferation, migration and invasion. Gaussia luciferase reporter assay, q-RT-PCR and western blotting assay were used to explore the underlying mechanism. Also, the A549 xenograft model was conducted to evaluate the anti-tumor effect of miR-206 in vivo.

Results

The results showed that miR-206 expression was decreased in NSCLC tissues and lung cancer cells. Further research demonstrated that miR-206 inhibited the proliferation, migration and invasion of A549 cells via negatively regulating Coronin-1C (CORO1C), and CORO1C deletion significantly rescues the miR-206 mediated inhibitory effect on A549 cells. Moreover, miR-206 exhibited a perfect anti-tumor effect in the A549 xenograft model.

Conclusion

Our study reveals that miR-206 functions as a tumor metastasis suppressor and sheds new light on the clinical significance of miR-206 in NSCLC therapy.

CRN2 binds to TIMP4 and MMP14 and promotes perivascular invasion of glioblastoma cells

CRN2 is an actin filament binding protein involved in the regulation of various cellular processes including cell migration and invasion. CRN2 has been implicated in the malignant progression of different types of human cancer. We used CRN2 knock-out mice for analyses as well as for crossbreeding with a Tp53/Pten knock-out glioblastoma mouse model. CRN2 knock-out mice were subjected to a phenotyping screen at the German Mouse Clinic. Murine glioblastoma tissue specimens as well as cultured murine brain slices and glioblastoma cell lines were investigated by immunohistochemistry, immunofluorescence, and cell biological experiments. Protein interactions were studied by immunoprecipitation, pull-down, and enzyme activity assays. CRN2 knock-out mice displayed neurological and behavioural alterations, e.g. reduced hearing sensitivity, reduced acoustic startle response, hypoactivity, and less frequent urination. While glioblastoma mice with or without the additional CRN2 knock-out allele exhibited no significant difference in their survival rates, the increased levels of CRN2 in transplanted glioblastoma cells caused a higher tumour cell encasement of murine brain slice capillaries. We identified two important factors of the tumour microenvironment, the tissue inhibitor of matrix metalloproteinase 4 (TIMP4) and the matrix metalloproteinase 14 (MMP14, synonym: MT1-MMP), as novel binding partners of CRN2. All three proteins mutually interacted and co-localised at the front of lamellipodia, and CRN2 was newly detected in exosomes. On the functional level, we demonstrate that CRN2 increased the secretion of TIMP4 as well as the catalytic activity of MMP14. Our results imply that CRN2 represents a pro-invasive effector within the tumour cell microenvironment of glioblastoma multiforme.

Notch1 and PI3K/Akt signaling blockers DAPT and LY294002 coordinately inhibit metastasis of gastric cancer through mutual enhancement

PURPOSE

Blockade of either Notch1 or PI3K/Akt pathway inhibits metastasis of gastric cancer. However, whether blockade of both pathways coordinately exerts such an effect remains unknown. In this study, we aimed to investigate the effects of combined treatment with Notch1 signaling blocker DAPT and PI3K/Akt signal blocker LY294002 on metastasis of gastric cancer.

METHODS

Notch intracellular domain (NICD) and phosphorylated Akt (p-Akt) levels in gastric cancer tissues and their adjacent normal tissue samples and gastric cancer SGC7901 and AGS cells and normal GES-1 cells were determined using immunohistochemistry and Western blotting. The effects of combined DAPT and LY294002 on metastasis of gastric cancer were evaluated by examining migration and invasion potential of SGC7901 cells using wound healing and transwell assays, determining changes in the levels of epithelial-mesenchymal transition biomarkers and MMP-9, Notch1, HES1, and phosphorylation of Akt in gastric cancer SGC7901 cells and/or AGS cells in vitro using Western blotting, and metastasis of gastric cancer to lungs in BALB/c nude mice after treatment.

RESULTS

NICD and p-Akt levels were significantly higher in gastric cancer tissues and SGC7901 and AGS cells than those in the normal control and GES-1 cells. Migration and invasion potential of SGC7901 cells, EMT biomarkers and MMP-9 in SGC7901 cells, and metastasis of gastric cancer to lungs in mice were coordinately inhibited by DAPT and LY294002. In addition, DAPT and LY294002 coordinately inhibited the levels of Notch1, HES1, and p-Akt in gastric cancer cells.

CONCLUSION

DAPT and LY294002 coordinately inhibited metastasis of gastric cancer through mutual enhancement.

Coronin3 Promotes Nasopharyngeal Carcinoma Migration And Invasion By Induction Of Epithelial-To-Mesenchymal Transition

Purpose

Coronin3 is a cytoskeletal protein that has been implicated in metastasis in many cancer types. Here, we demonstrate its effect in nasopharyngeal carcinoma (NPC) and propose a new probable mechanism of CORO1C-mediated cell migration and invasion by regulation of epithelial-to-mesenchymal transition (EMT) and CDH11.

Patients and methods

First, we measured the differential expression of CORO1C between NPC and non-NPC cells in both cell lines and clinical specimens, using public datasets. Then, we investigated its relationship with clinicopathological factors and its potential as a biomarker to predict the prognosis of NPC patients. We also explored its influence on the cell behaviors of migration and invasion by upregulating and downregulating the expression of CORO1C and attempted to determine the underlying mechanism.

Results

The results verified our original hypothesis. CORO1C was overexpressed in both NPC cell lines and clinical specimens, in both public datasets and our own samples. NPC patients with lower CORO1C expression levels in primary cancer tissues had longer OS (hazard ratio [HR] 1.814, 95% CI 0.831–3.960, p=0.0341) and PFS (HR 1.798, 95% CI 0.907–3.564, p=0.0155), indicating that it could be used as a prognostic biomarker. It was also confirmed that CORO1C enhanced cells’ migration and invasion abilities, by inducing morphological and marker changes typical of EMT. Finally, we found that expression was correlated with and regulated CDH11 expression in NPC cell lines.

Conclusion

Our study provided evidence for the contribution of CORO1C to NPC metastasis, and indicated that it could be used as a new therapeutic target and prognostic biomarker.

RCC2 promotes breast cancer progression through regulation of Wnt signaling and inducing EMT

Regulator of chromosome condensation 2 (RCC2), also known as TD-60, is an RCC1 family member and plays an essential role in mitosis. However, the roles of RCC2 in breast cancer are still unclear. In this study, RCC2 was found to exert oncogenic activities in breast cancer. Samples of breast cancer tissue revealed an increased level of RCC2 and a high level of RCC2 was associated with poor overall survival rate of breast cancer patients. Overexpression of RCC2 significantly enhanced cell proliferation and migration abilities of breast cancer cells in vitro and in vivo. Mechanistically, RCC2 induced epithelial-mesenchymal transition (EMT) through the activation of Wnt signaling pathway. Collectively, our study indicates that RCC2 contributes to breast cancer progression and functions as an important regulator of EMT through the activation of Wnt signaling.

miR-26 suppresses renal cell cancer via down-regulating coronin-3

Coronin-3 (coronin-1C), a homotrimer F-actin-binding protein, has been reported to be important for metastasis in several types of cancers such as lung cancer, gastric cancer, and breast cancer. Here, we present an investigation of the expression and function of coronin-3 in renal cell cancer for the first time. We also confirmed that miR-26 directly targets coronin-3 and down-regulates its expression by western blot assay and dual-luciferase reporter system. The results of MTT and colony formation assay showed that miR-26 suppressed cell proliferation. Wound healing and transwell assay revealed that miR-26 inhibited migration and invasion of renal cancer cell. Moreover, overexpression of coronin-3 could reverse the miR-26-induced inhibition in cell growth and metastasis. Thus, our study suggests that coronin-3 should serve as a potential therapeutic target in renal cell cancer and provide a candidate for miRNA therapy.

High WDR34 mRNA expression as a potential prognostic biomarker in patients with breast cancer as determined by integrated bioinformatics analysis

The WD-repeat domain (WDR) family is distributed in the majority of eukaryotes and has several unique biological functions. It serves important roles in signal transduction, cytoskeleton assembly, protein transport, RNA processing, chromatin modification and transcription mechanisms. WD repeat domain 34 (WDR34) has been recently identified as a member of the WDR family. Overexpression of WDR34 was accompanied by the presence of multiple centrioles in the cell, suggesting that it was associated with tumor occurrence. However, its association with breast cancer was unclear. To the best of our knowledge, it has not yet been confirmed whether WDR34 gene expression is associated with breast cancer. Therefore, the current study attempted to clarify this by performing a comprehensive study using multiple datasets in the Oncomine, Breast Cancer Gene-Expression Miner and Kaplan-Meier Plotter databases. The analysis indicated that the mRNA expression levels of WDR34 were increased in breast cancer tissues compared with normal tissues. Consistent with this result, the Broad-Novartis Cancer Cell Line Encyclopedia revealed that WDR34 mRNA expression levels were upregulated in breast cancer cell lines compared with other cancer cells. It was noted that high WDR34 mRNA expression was associated with forkhead box M1 and PTTG1 regulator of sister chromatid separation, securing in co-expression analysis. Expression profile characteristics of WDR34 mRNA were identified in different molecular subtypes of breast cancer. Furthermore, survival analysis revealed that increased expression levels of WDR34 mRNA were associated with poor overall survival in patients with breast cancer, particularly in luminal B, lymph node status-positive and estrogen receptor (ER)-negative subgroups. Additionally, Kaplan-Meier curves revealed that high WDR34 mRNA expression was associated with shorter relapse-free survival in patients with breast cancer, particularly in ER-positive, human epidermal growth factor receptor 2-negative and progesterone receptor-positive subgroups. These results suggested that WDR34 may be used as a prognosis predictor in breast cancer and may provide a novel target for the diagnosis and treatment of breast cancer.

Cathepsins: Potent regulators in carcinogenesis

Cathepsins (CTS) are mainly lysosomal acid hydrolases extensively involved in the prognosis of different diseases, and having a distinct role in tumor progression by regulating cell proliferation, autophagy, angiogenesis, invasion, and metastasis. As all these processes conjunctively lead to cancer progression, their site-specific regulation might be beneficial for cancer treatment. CTS regulate activation of the proteolytic cascade and protein turnover, while extracellular CTS is involved in promoting extracellular matrix degradation and angiogenesis, thereby stimulating invasion and metastasis. Despite cancer regulation, the involvement of CTS in cellular adaptation toward chemotherapy and radiotherapy augments their therapeutic potential. However, lysosomal permeabilization mediated cytosolic translocation of CTS induces programmed cell death. This complex behavior of CTS generates the need to discuss the different aspects of CTS associated with cancer regulation. In this review, we mainly focused on the significance of each cathepsin in cancer signaling and their targeting which would provide noteworthy information in the context of cancer biology and therapeutics.

SHCBP1 is a novel target and exhibits tumor‑promoting effects in gastric cancer

The present study investigated the expression and potential influence of SHC SH2 domain-binding protein 1 (SHCBP1) in gastric cancer (GC) cells. SHCBP1 is closely related to cell proliferation and cell cycle progression, but its role in GC remains unclear. The TCGA database revealed that SHCBP1 is highly expressed in GC tissues. Furthermore, SHCBP1 was revealed to be highly expressed in GC cell lines MGC-803 and SGC-7901 cells, and downregulation of SHCBP1 significantly inhibited GC cell proliferation. Furthermore, SHCBP1 expression promoted cell cycle progression and inhibition of apoptosis. Since the CDK4, cyclin D1 and caspase family proteins play important roles in cell cycle and apoptosis regulation, it was examined whether there was an association between SHCBP1 and these signaling pathways in GC. Our results revealed that SHCBP1 promoted cell cycle progression by regulating the CDK4-cyclin D1 cascade and suppressed caspase-3, caspase PARP-dependent apoptotic pathways. Cell invasion and metastasis experiments also revealed that SHCBP1 promoted tumor growth and invasiveness. These tumor-promoting functions of SHCBP1 may provide a potential molecular basis for the diagnosis and targeted therapy of GC.

Coronin 1C promotes triple-negative breast cancer invasiveness through regulation of MT1-MMP traffic and invadopodia function

Membrane type 1-matrix metalloproteinase (MT1-MMP), a membrane-tethered protease, is key for matrix breakdown during cancer invasion and metastasis. Assembly of branched actin networks by the Arp2/3 complex is required for MT1-MMP traffic and formation of matrix-degradative invadopodia. Contrasting with the well-established role of actin filament branching factor cortactin in invadopodia function during cancer cell invasion, the contribution of coronin-family debranching factors to invadopodia-based matrix remodeling is not known. Here, we investigated the contribution of coronin 1C to the invasive potential of breast cancer cells. We report that expression of coronin 1C is elevated in invasive human breast cancers, correlates positively with MT1-MMP expression in relation with increased metastatic risk and is a new independent prognostic factor in breast cancer. We provide evidence that, akin to cortactin, coronin 1C is required for invadopodia formation and matrix degradation by breast cancer cells lines and for 3D collagen invasion by multicellular spheroids. Using intravital imaging of orthotopic human breast tumor xenografts, we find that coronin 1C accumulates in structures forming in association with collagen fibrils in the tumor microenvironment. Moreover, we establish the role of coronin 1C in the regulation of positioning and trafficking of MT1-MMP-positive endolysosomes. These results identify coronin 1C as a novel player of the multi-faceted mechanism responsible for invadopodia formation, MT1-MMP surface exposure and invasiveness in breast cancer cells.

Cysteine cathepsins as a prospective target for anticancer therapies-current progress and prospects

Cysteine cathepsins (CTS), being involved in both physiological and pathological processes, play an important role in the human body. During the last 30 years, it has been shown that CTS are highly upregulated in a wide variety of cancer types although they have received a little attention as a potential therapeutic target as compared to serine or metalloproteinases. Studies on the increasing problem of neoplastic progression have revealed that secretion of cell-surface- and intracellular cysteine proteases is aberrant in tumor cells and has an impact on their growth, invasion, and metastasis by taking part in tumor angiogenesis, in apoptosis, and in events of inflammatory and immune responses. Considering the role of CTS in carcinogenesis, inhibition of these enzymes becomes an attractive strategy for cancer therapy. The downregulation of natural CTS inhibitors (CTSsis), such as cystatins, observed in various types of cancer, supports this claim. The intention of this review is to highlight the relationship of CTS with cancer and to present illustrations that explain how some of their inhibitors affect processes related to neoplastic progression.

Molecular alterations of cancer cell and tumour microenvironment in metastatic gastric cancer

The term metastasis is widely used to describe the endpoint of the process by which tumour cells spread from the primary location to an anatomically distant site. Achieving successful dissemination is dependent not only on the molecular alterations of the cancer cells themselves, but also on the microenvironment through which they encounter. Here, we reviewed the molecular alterations of metastatic gastric cancer (GC) as it reflects a large proportion of GC patients currently seen in clinic. We hope that further exploration and understanding of the multistep metastatic cascade will yield novel therapeutic targets that will lead to better patient outcomes.

Cathepsins in digestive cancers

Cathepsins are lysosomal peptidases belonging to the papain family, and based on their catalytic sites, these enzymes can be divided into serine, cysteine and aspartic proteases. The studies conducted to date have identified, 15 types of cathepsins that are widely distributed in intracellular and extracellular spaces. These proteases participate in various pathological activities, including the occurrence and development of human cancers. Several recent studies suggest that cathepsins, particularly cathepsins B, D, E and L, contribute to digestive tumorigenesis. Cathepsins were found to promote the development of most digestive cancers except liver cancer, in which they might have the opposite effects. Due to their important roles in digestive tumors, cathepsins might be therapeutic targets for the treatment of digestive cancers.

Coronin 3 negatively regulates G6PC3 in HepG2 cells, as identified by label‑free mass‑spectrometry

Human coronin 3 is involved in many types of cancers, but the underlying molecular mechanisms require further elucidation. The present study demonstrated that coronin 3 is significantly upregulated in clinical primary hepatocellular carcinoma (HCC) samples by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and immunohistochemical staining. Subsequently, proteins that were regulated by coronin 3 in both coronin 3 overexpressing or knocked down HepG2 cells were analyzed by label free mass spectrometry; overall, 249 proteins were identified to be closely regulated by coronin 3, and those coronin 3 regulated proteins were enriched in cellular, physiological and metabolism processes. By further in‑depth pathway analysis, it was demonstrated that those proteins were involved into 94 different pathways. Finally, the expression levels of glucose‑6‑phosphatase catalytic subunit 3 (G6PC3) were confirmed to be negatively regulated by coronin 3, as determined by RT‑qPCR and western blotting. In conclusion, these results indicated that coronin3 is significantly dysregulated in HCC tumor tissues, and may exert its function via regulating G6PC3 expression. These results provide valuable information for further study of coronin 3‑mediated signaling pathways, and implicate coronin 3 as a potential therapeutic target for HCC.

Regulation of actin-binding protein ANLN by antitumor miR-217 inhibits cancer cell aggressiveness in pancreatic ductal adenocarcinoma

Analysis of our microRNA (miRNA) expression signature of pancreatic ductal adenocarcinoma (PDAC) revealed that microRNA-217 (miR-217) was significantly reduced in cancer tissues. The aim of this study was to investigate the antitumor roles of miR-217 in PDAC cells and to identify miR-217-mediated molecular pathways involved in PDAC aggressiveness. The expression levels of miR-217 were significantly reduced in PDAC clinical specimens. Ectopic expression of miR-217 significantly suppressed cancer cell migration and invasion. Transcription of actin-binding protein Anillin (coded by ANLN) was detected by our in silico and gene expression analyses. Moreover, luciferase reporter assays showed that ANLN was a direct target of miR-217 in PDAC cells. Overexpression of ANLN was detected in PDAC clinical specimens by real-time PCR methods and immunohistochemistry. Interestingly, Kaplan-Meier survival curves showed that high expression of ANLN predicted shorter survival in patients with PDAC by TCGA database analysis. Silencing ANLN expression markedly inhibited cancer cell migration and invasion capabilities of PDAC cell lines. We further investigated ANLN-mediated downstream pathways in PDAC cells. "Focal adhesion" and "Regulation of actin binding protein" were identified as ANLN-modulated downstream pathways in PDAC cells. Identification of antitumor miR-217/ANLN-mediated PDAC pathways will provide new insights into the potential mechanisms underlying the aggressive course of PDAC.

YBX1 gene silencing inhibits migratory and invasive potential via CORO1C in breast cancer in vitro

BACKGROUND

Y-box binding protein-1 is an evolutionary conserved transcription and translation regulating protein that is overexpressed in various human malignancies, including breast cancer. Despite reports of YB-1 and its association with distant spread of breast cancer, the intrinsic mechanism underlying this observation remains elusive. This study investigates the role of YB-1 in mediating metastasis in highly invasive breast cancer cell lines.

METHODS

Silencing the YBX1 gene (which encodes the YB-1 protein) by small interfering RNA (siRNA) was performed in MDA-MB-231 and Hs578T breast cancer cell lines, followed by phenotypic assays including cell migration and invasion assays. Gene expression profiling using Affymetrix GeneChip® Human Transcriptome 2.0 array was subsequently carried out in YB-1 silenced MDA-MB-231 cells. Overexpression and silencing of YBX1 were performed to assess the expression of CORO1C, one of the differentially regulated genes from the transcriptomic analysis. A Gaussia luciferase reporter assay was used to determine if CORO1C is a putative YB-1 downstream target. siRNA-mediated silencing of CORO1C and down-regulation of YBX1 in CORO1C overexpressing MDA-MB-231 cells were performed to evaluate cell migration and invasion.

RESULTS

Downregulation of the YB-1 protein inhibited cell migration and invasion in MDA-MB-231 breast cancer cells. Global gene expression profiling in the YBX1 silenced MDA-MB-231 cells identified differential expression of several genes, including CORO1C (which encodes for an actin binding protein, coronin-1C) as a potential downstream target of YB-1. While knockdown of YBX1 gene decreased CORO1C gene expression, the opposite effects were seen in YB-1 overexpressing cells. Subsequent verification using the reporter assay revealed that CORO1C is an indirect downstream target of YB-1. Silencing of CORO1C by siRNA in MDA-MB-231 cells was also observed to reduce cell migration and invasion. Silencing of YBX1 caused a similar reduction in CORO1C expression, concomitant with a significant decrease in migration in Hs578T cells. In coronin-1C overexpressing MDA-MB-231 cells, increased migration and invasion were abrogated by YB-1 knockdown.

CONCLUSION

It would appear that YB-1 could regulate cell invasion and migration via downregulation of its indirect target coronin-1C. The association between YB-1 and coronin-1C offers a novel approach by which metastasis of breast cancer cells could be targeted and abrogated.

Coronin 1C-free primary mouse fibroblasts exhibit robust rearrangements in the orientation of actin filaments, microtubules and intermediate filaments

Coronin 1C is an established modulator of actin cytoskeleton dynamics. It has been shown to be involved in protrusion formation, cell migration and invasion. Here, we report the generation of primary fibroblasts from coronin 1C knock-out mice in order to investigate the impact of the loss of coronin 1C on cellular structural organisation. We demonstrate that the lack of coronin 1C not only affects the actin system, but also the microtubule and the vimentin intermediate filament networks. In particular, we show that the knock-out cells exhibit a reduced proliferation rate, impaired cell migration and protrusion formation as well as an aberrant subcellular localisation and function of mitochondria. Moreover, we demonstrate that coronin 1C specifically interacts with the non-α-helical amino-terminal domain ("head") of vimentin. Our data suggest that coronin 1C acts as a cytoskeletal integrator of actin filaments, microtubules and intermediate filaments.

Coronin 2A (CRN5) expression is associated with colorectal adenoma-adenocarcinoma sequence and oncogenic signalling

BACKGROUND

Coronin proteins are known as regulators of actin-based cellular processes, and some of them are associated with the malignant progression of human cancer. Here, we show that expression of coronin 2A is up-regulated in human colon carcinoma.

METHODS

This study included 26 human colon tumour specimens and 9 normal controls. Expression and localisation of coronin 2A was studied by immunohistochemistry, immunofluorescence imaging, cell fractionation, and immunoblotting. Functional roles of coronin 2A were analysed by over-expression and knock-down of the protein. Protein interactions were studied by co-immunoprecipitation and pull-down experiments, mass spectrometry analyses, and in vitro kinase and methylation assays.

RESULTS

Histopathological investigation revealed that the expression of coronin 2A in colon tumour cells is up-regulated during the adenoma-adenocarcinoma progression. At the subcellular level, coronin 2A localised to multiple compartments, i.e. F-actin stress fibres, the front of lamellipodia, focal adhesions, and the nuclei. Over-expression of coronin 2A led to a reduction of F-actin stress fibres and elevated cell migration velocity. We identified two novel direct coronin 2A interaction partners. The interaction of coronin 2A with MAPK14 (mitogen activated protein kinase 14 or MAP kinase p38α) led to phosphorylation of coronin 2A and also to activation of the MAPK14 pathway. Moreover, coronin 2A interacted with PRMT5 (protein arginine N-methyltransferase 5), which modulates the sensitivity of tumour cells to TRAIL-induced cell death.

CONCLUSIONS

We show that increased expression of coronin 2A is associated with the malignant phenotype of human colon carcinoma. Moreover, we linked coronin 2A to MAPK14 and PRMT5 signalling pathways involved in tumour progression.

miR-206 inhibits cell migration through direct targeting of the actin-binding protein coronin 1C in triple-negative breast cancer

Patients with triple-negative breast cancer (TNBC) have an overall poor prognosis, which is primarily due to a high metastatic capacity of these tumors. Novel therapeutic approaches to target the signaling pathways that promote metastasis are desirable, in order to improve the outcome for these patients. A loss of function of a microRNA, miR-206, is related to increased metastasis potential in breast cancers but the mechanism is not known. In this study, we show that miR-206 was decreased in TNBC clinical tumor samples and cell lines whereas one of its predicted targets, actin-binding protein CORO1C, was increased. Expression of miR-206 significantly reduced proliferation and migration while repressing CORO1C mRNA and protein levels. We demonstrate that miR-206 interacts with the 3'-untranslated region (3'-UTR) of CORO1C and regulates this gene post-transcriptionally. This post-transcriptional regulation was dependent on two miR-206-binding sites within the 3'-UTR of CORO1C and was relieved by mutations of corresponding sites. Further, silencing of CORO1C reduced tumor cell migration and affected the actin skeleton and cell morphology, similar to miR-206 expression, but did not reduce proliferation. In accordance with this, overexpression of CORO1C rescued the inhibitory effect of miR-206 on cell migration. Our findings suggest that miR-206 represses tumor cell migration through direct targeting of CORO1C in TNBC cells which modulates the actin filaments. This pathway is a novel mechanism that offers a mechanistic basis through which the metastatic potential of TNBC tumors could be targeted.

Coronin3 regulates gastric cancer invasion and metastasis by interacting with Arp2

Coronin3 expression is increased in gastric cancer (GC) tissues and can promote GC invasion and metastasis. However, the mechanisms underlying Coronin3 function in GC remain unclear. In this study, we aimed to explore the interacting molecules essential for the tumor-promoting effects of Coronin3 in GC. Using mass spectrometric analysis, functional studies, and immunohistochemistry, we found that Arp2 interacted with Coronin3, and ectopic expression of Arp2 promoted GC cell migration and invasion, while Arp2 knockdown suppressed whole-cell motility and attenuated the Coronin3-mediated upregulation of cell migration and invasion. In addition, both proteins correlated with the metastatic status of GC patients. Furthermore, survival analyses demonstrated that both Coronin3 and Arp2 correlated with overall GC patient survival, and the combination of Coronin3 and Arp2 most accurately predicted GC patient prognosis. Combined, these data demonstrate that Coronin3 can regulate GC invasion and metastasis through Arp2, and the combination of Coronin3 and Arp2 provides a potential marker for predicting GC prognosis.

MicroRNA-206 suppresses gastric cancer cell growth and metastasis

Gastric cancer is one of the leading causes of cancer death world-wide and carries a high rate of metastatic risk. In addition to other protein-coding oncogenes and tumor suppressor genes, microRNAs play an important role in gastric cancer tumorigenic progression. Here, we show that miR-206 is expressed at markedly low levels in a cohort of gastric tumors compared to their matching normal tissues, and in a number of gastric cancer cell lines. Down-regulation of miR-206 was particularly significant in tumors with lymphatic metastasis, local invasion, and advanced TNM staging. We find that forced expression of miR-206 suppressed the proliferation, colony-formation, and xenograft tumorigenesis of SCG-7901 cells, a line of gastric cancer cells. Forced expression of miR-206 also suppressed SCG-7901 cell migration and invasion, as well as metastasis in cell culture or tail-vein injected mouse models, respectively. The anti-metastatic effect of miR-206 is likely mediated by targeting metastasis regulatory genes STC2, HDAC4, KLF4, IGF1R, FRS2, SFRP1, BCL2, BDNF, and K-ras, which were drastically down-regulated by stable expression of exogenous miR-206 in SCG-7901 cells. Taken together, our results indicate that miR-206 is a tumor suppressor of gastric cancer acting at steps that regulate metastasis.

RhoE promotes metastasis in gastric cancer through a mechanism dependent on enhanced expression of CXCR4

RhoE, a novel member of the Rho protein family, is a key regulator of the cytoskeleton and cell migration. Our group has previously shown that RhoE as a direct target for HIF-1α and mediates hypoxia-induced epithelial to mesenchymal transition in gastric cancer cells. Therefore, we assumed that RhoE might play an important role in gastric cancer metastasis. In the present study, we have explored the role of RhoE expression in gastric cancer, cell invasion and metastasis, and the influence of RhoE on regulating the potential expression of down-stream genes. RhoE expression was elevated in gastric cancer tissues as compared with normal gastric tissues. We also found a close correlation between the histological grade and the diagnosis of the patient. Up-regulation of RhoE significantly enhanced the migratory and invasive abilities of gastric cancer cells both in vitro and in vivo. Moreover, down-regulation of RhoE diminished the metastatic potential of cancer cells. PCR array and subsequent transwell assay showed that the regulation of gastric cancer metastasis by RhoE was partially mediated by CXCR4. This observation suggested that CXCR4 might be a downstream effector for RhoE. In summary, our study identified RhoE as a novel prognostic biomarker and metastatic-promoting gene of gastric cancer.

Cathepsins mediate tumor metastasis

Cathepsins are highly expressed in various human cancers, associated with tumor metastasis. It is superfamily, concluding A, B, C, D, E, F, G, H, L, K, O, S, V, and W family members. As a group of lysosomal proteinases or endopeptidases, each member has a different function, playing different roles in distinct tumorigenic processes such as proliferation, angiogenesis, metastasis, and invasion. Cathepsins belong to a diverse number of enzyme subtypes, including cysteine proteases, serine proteases and aspartic proteases. The contribution of cathepsins to invasion in human cancers is well documented, although the precise mechanisms by which cathepsins exert their effects are still not clear. In the present review, the role of cathepsin family members in cancer is discussed.

CRN2 enhances the invasiveness of glioblastoma cells

BACKGROUND

Movement of tumor cells involves dynamic remodeling of the actin cytoskeleton, which is regulated by actin binding proteins, such as CRN2 (synonyms: coronin 1C, coronin 3). In vitro, CRN2 participates in secretion, matrix degradation, protrusion formation, and cell migration. Furthermore, expression of CRN2 correlates with the malignant phenotype of human diffuse gliomas. CRN2's effects on actin polymerization and F-actin bundling are abolished by protein kinase 2 (CK2) dependent phosphorylation at serine 463.

METHODS

We generated human U373 glioblastoma cell lines with knock-down of CRN2 or over-expression of CRN2 variants and studied their behavior in vitro and ex vivo in organotypic brain slice cultures.

RESULTS

CRN2 over-expression and expression of the S463A phospho-resistant CRN2 variant increase proliferation, matrix degradation, and invasion but decrease adhesion and formation of invadopodia-like extensions in vitro. Knock-down of CRN2 and expression of S463D phospho-mimetic CRN2 generally have opposite effects. Analysis of invadopodia-like cell extensions shows a diffuse relocalization of F-actin in CRN2 knockdown cells, whereas expression of S463A and S463D mutant CRN2 causes enrichments of F-actin structures at the center and rime zone, respectively. Fluorescence recovery after photobleaching studies of CRN2 and F-actin in lamellipodia show that both CRN2 variants decrease the turnover of actin filaments. Glioblastoma cells over-expressing wild-type or S463A CRN2, which were transplanted onto brain slices, characteristically developed into tumors with an invasive phenotype.

CONCLUSIONS

Overall, our data indicate that CRN2 participates in cancer progression via modulation of the actin cytoskeleton.