scholarly journals Reduced DOCK4 expression leads to erythroid dysplasia in myelodysplastic syndromes

2015 ◽  
Vol 112 (46) ◽  
pp. E6359-E6368 ◽  
Author(s):  
Sriram Sundaravel ◽  
Ryan Duggan ◽  
Tushar Bhagat ◽  
David L. Ebenezer ◽  
Hui Liu ◽  
...  

Anemia is the predominant clinical manifestation of myelodysplastic syndromes (MDS). Loss or deletion of chromosome 7 is commonly seen in MDS and leads to a poor prognosis. However, the identity of functionally relevant, dysplasia-causing, genes on 7q remains unclear. Dedicator of cytokinesis 4 (DOCK4) is a GTPase exchange factor, and its gene maps to the commonly deleted 7q region. We demonstrate that DOCK4 is underexpressed in MDS bone marrow samples and that the reduced expression is associated with decreased overall survival in patients. We show that depletion of DOCK4 levels leads to erythroid cells with dysplastic morphology both in vivo and in vitro. We established a novel single-cell assay to quantify disrupted F-actin filament network in erythroblasts and demonstrate that reduced expression of DOCK4 leads to disruption of the actin filaments, resulting in erythroid dysplasia that phenocopies the red blood cell (RBC) defects seen in samples from MDS patients. Reexpression of DOCK4 in −7q MDS patient erythroblasts resulted in significant erythropoietic improvements. Mechanisms underlying F-actin disruption revealed that DOCK4 knockdown reduces ras-related C3 botulinum toxin substrate 1 (RAC1) GTPase activation, leading to increased phosphorylation of the actin-stabilizing protein ADDUCIN in MDS samples. These data identify DOCK4 as a putative 7q gene whose reduced expression can lead to erythroid dysplasia.

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Jun Liu ◽  
Jipeng Li ◽  
Ke Wang ◽  
Haiming Liu ◽  
Jianyong Sun ◽  
...  

AbstractFork-head box protein M1 (FoxM1) is a transcriptional factor which plays critical roles in cancer development and progression. However, the general regulatory mechanism of FoxM1 is still limited. STMN1 is a microtubule-binding protein which can inhibit the assembly of microtubule dimer or promote depolymerization of microtubules. It was reported as a major responsive factor of paclitaxel resistance for clinical chemotherapy of tumor patients. But the function of abnormally high level of STMN1 and its regulation mechanism in cancer cells remain unclear. In this study, we used public database and tissue microarrays to analyze the expression pattern of FoxM1 and STMN1 and found a strong positive correlation between FoxM1 and STMN1 in multiple types of cancer. Lentivirus-mediated FoxM1/STMN1-knockdown cell lines were established to study the function of FoxM1/STMN1 by performing cell viability assay, plate clone formation assay, soft agar assay in vitro and xenograft mouse model in vivo. Our results showed that FoxM1 promotes cell proliferation by upregulating STMN1. Further ChIP assay showed that FoxM1 upregulates STMN1 in a transcriptional level. Prognostic analysis showed that a high level of FoxM1 and STMN1 is related to poor prognosis in solid tumors. Moreover, a high co-expression of FoxM1 and STMN1 has a more significant correlation with poor prognosis. Our findings suggest that a general FoxM1-STMN1 axis contributes to cell proliferation and tumorigenesis in hepatocellular carcinoma, gastric cancer and colorectal cancer. The combination of FoxM1 and STMN1 can be a more precise biomarker for prognostic prediction.


2021 ◽  
pp. 1-10
Author(s):  
Yu Wang ◽  
Han Zhao ◽  
Ping Zhao ◽  
Xingang Wang

BACKGROUND: Pyruvate kinase M2 (PKM2) was overexpressed in many cancers, and high PKM2 expression was related with poor prognosis and chemoresistance. OBJECTIVE: We investigated the expression of PKM2 in breast cancer and analyzed the relation of PKM2 expression with chemotherapy resistance to the neoadjuvant chemotherapy (NAC). We also investigated whether PKM2 could reverse chemoresistance in breast cancer cells in vitro and in vivo. METHODS: Immunohistochemistry (IHC) was performed in 130 surgical resected breast cancer tissues. 78 core needle biopsies were collected from breast cancer patients before neoadjuvant chemotherapy. The relation of PKM2 expression and multi-drug resistance to NAC was compared. The effect of PKM2 silencing or overexpression on Doxorubicin (DOX) sensitivity in the MCF-7 cells in vitro and in vivo was compared. RESULTS: PKM2 was intensively expressed in breast cancer tissues compared to adjacent normal tissues. In addition, high expression of PKM2 was associated with poor prognosis in breast cancer patients. The NAC patients with high PKM2 expression had short survival. PKM2 was an independent prognostic predictor for surgical resected breast cancer and NAC patients. High PKM2 expression was correlated with neoadjuvant treatment resistance. High PKM2 expression significantly distinguished chemoresistant patients from chemosensitive patients. In vitro and in vivo knockdown of PKM2 expression decreases the resistance to DOX in breast cancer cells in vitro and tumors in vivo. CONCLUSION: PKM2 expression was associated with chemoresistance of breast cancers, and could be used to predict the chemosensitivity. Furthermore, targeting PKM2 could reverse chemoresistance, which provides an effective treatment methods for patients with breast cancer.


2018 ◽  
Vol 243 (7) ◽  
pp. 645-654 ◽  
Author(s):  
Yi-Quan Yan ◽  
Juan Xie ◽  
Jing-Fu Wang ◽  
Zhao-Feng Shi ◽  
Xiang Zhang ◽  
...  

Hepatocellular carcinoma (HCC) is one of the most malignant diseases worldwide. The unfavorable clinical outcome and poor prognosis are due to high rates of recurrence and metastasis after treatments. Some scholars of traditional Chinese medicine suggested that endogenous wind-evil had played an important role in metastasis of malignant tumor. Therefore, the drug of dispelling wind-evil could be used to prevent cancer metastasis and improve the poor prognosis. So we wondered whether Scorpion, one of the most important wind calming drugs, has antitumor effect especially in epithelial–mesenchymal transition (EMT) and metastasis of HCC in this research. We found that Scorpion-medicated serum could inhibit proliferation, induce apoptosis, and decrease migration and invasion capacity of Hepa1-6 cells in vitro. Meanwhile, we observed that water decoction of Scorpion restrained tumor growth and metastasis in nude mouse of HCC metastasis models. Further experiments showed that Scorpion could suppress EMT, which is characterized by increased epithelial marker E-cadherin expression and decreased mesenchymal markers N-cadherin and Snail expression following Scorpion treatment both in vitro and in vivo. These results suggested that the Scorpion could inhibit Hepa1-6 cells’ invasion and metastasis in part by reversing EMT and providing a possible potential approach for preventing HCC metastasis. Impact statement The unfavorable clinical outcome and poor prognosis of hepatocellular carcinoma (HCC) are due to high rates of recurrence and metastasis after treatments. Here we found Scorpion, one of the most important wind calming drugs, has antitumor effect. Scorpion-medicated serum inhibited the proliferation, induced apoptosis, and decreased migration and invasion capacity of Hepa1-6 cells in vitro. Water decoction of Scorpion restrained tumor growth and metastasis in nude mouse of HCC metastasis models. Further experiments showed that Scorpion could suppress EMT of HCC both in vitro and in vivo. Our results suggested that the Scorpion could inhibit Hepa1-6 cells’ invasion and metastasis in part by reversing EMT and providing a possible potential approach for preventing HCC metastasis.


2006 ◽  
Vol 26 (13) ◽  
pp. 4830-4842 ◽  
Author(s):  
Sonja G. Hunter ◽  
Guanglei Zhuang ◽  
Dana Brantley-Sieders ◽  
Wojciech Swat ◽  
Christopher W. Cowan ◽  
...  

ABSTRACT Angiogenesis, the process by which new blood vessels are formed from preexisting vasculature, is critical for vascular remodeling during development and contributes to the pathogenesis of diseases such as cancer. Prior studies from our laboratory demonstrate that the EphA2 receptor tyrosine kinase is a key regulator of angiogenesis in vivo. The EphA receptor-mediated angiogenic response is dependent on activation of Rho family GTPase Rac1 and is regulated by phosphatidylinositol 3-kinase. Here we report the identification of Vav2 and Vav3 as guanine nucleotide exchange factors (GEFs) that link the EphA2 receptor to Rho family GTPase activation and angiogenesis. Ephrin-A1 stimulation recruits the binding of Vav proteins to the activated EphA2 receptor. The induced association of EphA receptor and Vav proteins modulates the activity of Vav GEFs, leading to activation of Rac1 GTPase. Overexpression of either Vav2 or Vav3 in primary microvascular endothelial cells promotes Rac1 activation, cell migration, and assembly in response to ephrin-A1 stimulation. Conversely, loss of Vav2 and Vav3 GEFs inhibits Rac1 activation and ephrin-A1-induced angiogenic responses both in vitro and in vivo. In addition, embryonic fibroblasts derived from Vav2−/− Vav3−/− mice fail to spread on an ephrin-A1-coated surface and exhibit a significant decrease in the formation of ephrin-A1-induced lamellipodia and filopodia. These findings suggest that Vav GEFs serve as a molecular link between EphA2 receptors and the actin cytoskeleton and provide an important mechanism for EphA2-mediated angiogenesis.


Cancers ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 491 ◽  
Author(s):  
Heng-Wei Liu ◽  
Yu-Kai Su ◽  
Oluwaseun Bamodu ◽  
Dueng-Yuan Hueng ◽  
Wei-Hwa Lee ◽  
...  

Background: Glioblastoma (GBM), a malignant form of glioma, is characterized by resistance to therapy and poor prognosis. Accumulating evidence shows that the initiation, propagation, and recurrence of GBM is attributable to the presence of GBM stem cells (GBM-CSCs). Experimental approach: Herein, we investigated the effect of 4-Acetylantroquinonol B (4-AAQB), a bioactive isolate of Antrodia cinnamomea, on GBM cell viability, oncogenic, and CSCs-like activities. Results: We observed that aberrant expression of catenin is characteristic of GBM, compared to other glioma types (p = 0.0001, log-rank test = 475.2), and correlates with poor prognosis of GBM patients. Lower grade glioma and glioblastoma patients (n = 1152) with low catenin expression had 25% and 21.5% better overall survival than those with high catenin expression at the 5 and 10-year time-points, respectively (p = 3.57e-11, log-rank test = 43.8). Immunohistochemistry demonstrated that compared with adjacent non-tumor brain tissue, primary and recurrent GBM exhibited enhanced catenin expression (~10-fold, p < 0.001). Western blot analysis showed that 4-AAQB significantly downregulated β-catenin and dysregulated the catenin/LEF1/Stat3 signaling axis in U87MG and DBTRG-05MG cells, dose-dependently. 4-AAQB–induced downregulation of catenin positively correlated with reduced Sox2 and Oct4 nuclear expression in the cells. Furthermore, 4-AAQB markedly reduced the viability of U87MG and DBTRG-05MG cells with 48 h IC50 of 9.2 M and 12.5 M, respectively, effectively inhibited the nuclear catenin, limited the migration and invasion of GBM cells, with concurrent downregulation of catenin, vimentin, and slug; similarly, colony and tumorsphere formation was significantly attenuated with reduced expression of c-Myc and KLF4 proteins. Conclusions: Summarily, we show for the first time that 4-AAQB suppresses the tumor-promoting catenin/LEF1/Stat3 signaling, and inhibited CSCs-induced oncogenic activities in GBM in vitro, with in vivo validation; thus projecting 4-AAQB as a potent therapeutic agent for anti-GBM target therapy.


Blood ◽  
1987 ◽  
Vol 70 (2) ◽  
pp. 524-530
Author(s):  
PA Janmey ◽  
SE Lind

Human blood depolymerizes filamentous (F-)actin. The interaction of actin filaments and monomers with human serum was studied by following the kinetics and extent of the depolymerization of pyrene-labeled F- actin and by analysis of serum proteins adhering to immobilized actin monomers. In physiologic Ca2+ concentrations, the depolymerization of F- actin proceeds in two stages: a rapid phase, attributed to direct severing of filaments by plasma gelsolin, and a slow phase attributed to the binding of actin monomers to vitamin D-binding protein (DBP). Without Ca2+, only the slow phase is observed. Human serum can completely depolymerize 10 to 18 mumol/L of actin, of which approximately 5 mumol/L occurs rapidly. Depolymerization can be accounted for by the normal serum concentrations of gelsolin and DBP. Fibrin(ogen) and fibronectin, which bind actin in vitro, do not contribute to the kinetics or extent of its depolymerization. Affinity chromatography and functional assays for the presence of gelsolin-actin complexes show that addition of G-actin to serum results in preferential formation of actin-DBP complexes, but that addition of F- actin to serum produces both gelsolin-actin complexes and DBP-actin complexes. The distinctive binding of actin monomers and polymers to these two serum proteins suggests a means by which their coordinated actions are maximized in vivo, from the standpoint of depolymerizing filaments and clearing monomers from the circulation.


2021 ◽  
Author(s):  
Wang Zhang ◽  
Zhendong Liu ◽  
Binchao Liu ◽  
Miaomiao Jiang ◽  
Shi Yan ◽  
...  

Abstract Background: Although many biomarkers have been reported for detecting glioma, the prognosis for the disease remains poor, and therefore, new biomarkers need to be identified. GNG5, which is part of the G-protein family, has been associated with different malignant tumors, though the role of GNG5 in glioma has not been studied. Therefore, we aimed to identify the relationship between GNG5 and glioma prognosis and identify a new biomarker for the diagnosis and treatment of gliomas.Methods: We used data on more than a thousand gliomas from multiple databases and clinical data to determine the expression of GNG5 in glioma. Based on clinical data and CGGA database, we identified the correlation between GNG5 and multiple molecular and clinical features and prognosis using various analytical methods. Co-expression analysis and GSEA were performed to detect GNG5-related genes in glioma and possible signaling pathways involved. ESTIMATE, ssGSEA, and TIMER were used to detect the relationship between GNG5 and the immune microenvironment. Functional experiments were performed to explore the function of GNG5 in glioma cells.Results: GNG5 is highly expressed in gliomas, and its expression level is positively correlated with pathological grade, histological type, age, and tumor recurrence and negatively correlated with isocitrate dehydrogenase mutation, 1p/19 co-deletion, and chemotherapy. Moreover, GNG5 as an independent risk factor was negatively correlated with the overall survival time. GSEA revealed the potential signaling pathways involved in GNG5 function in gliomas, including cell adhesion molecules signaling pathway. The ssGSEA, ESTIMATE, and TIMER based analysis indicated a correlation between GNG5 expression and various immune cells in glioma. In vivo and in vitro experiments showed that GNG5 could participate in glioma cell proliferation and migration.Conclusions: Based on the large data platform and the use of different databases to corroborate results obtained using various datasets, as well as in vitro and in vivo experiments, our study reveals for the first time that GNG5, as an oncogene, is overexpressed in gliomas and can inhibit the proliferation and migration of glioma cells and lead to poor prognosis of patients. Thus, GNG5 is a potential novel biomarker for the clinical diagnosis and treatment of gliomas.


2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Wenjing Shang ◽  
Zhongdong Xie ◽  
Fengying Lu ◽  
Daoquan Fang ◽  
Tianbin Tang ◽  
...  

Background. Thioredoxin-1 (Trx-1) is a small redox protein, which plays an important role in many biological processes. Although increased expression of Trx-1 in various solid tumors has been reported, the prognostic significance and function of Trx-1 in human gastric cancer (GC) are still unclear. Here, we investigated the clinical and prognostic significance of Trx-1 expression and the function and mechanism of Trx-1 in human GC. Methods. We analyzed Trx-1 mRNA expression from the GEO database and Trx-1 protein expression in 144 GC tissues using immunohistochemistry. Effects of Trx-1 on GC cell were assessed in vitro and in vivo through Trx-1 knockdown or overexpression. The antitumor effects of the Trx-1 inhibitor, PX-12, on GC cells were investigated. PTEN and p-AKT expressions were evaluated by Western blotting. Results. Increased Trx-1 expression was found in GC tissues and associated with poor prognosis and aggressive clinicopathological characteristics in patients with GC. High Trx-1 expression predicted poor prognosis, and its expression was an independent prognostic factor for overall survival of GC patients. Knockdown of Trx-1 expression inhibited GC cell growth, migration, and invasion in vitro and tumor growth and lung metastasis in vivo. Conversely, overexpression of Trx-1 promoted GC cell growth, migration, and invasion. We also found that PX-12 inhibited GC cell growth, migration, and invasion. Overexpression of Trx-1 caused a decrease in PTEN and increase in p-AKT levels whereas silencing Trx-1 caused an increase in PTEN and decrease in p-AKT levels in GC cells. Inhibition of AKT signaling pathway by MK2206 also inhibited GC cell growth, migration, and invasion. Conclusion. Our results indicate that Trx-1 may be a promising prognostic indicator and therapeutic target for GC patients.


Author(s):  
Mu-Su Pan ◽  
Hui Wang ◽  
Kamar Hasan Ansari ◽  
Xin-Ping Li ◽  
Wei Sun ◽  
...  

Abstract Background Cancer-associated fibroblasts (CAFs) and vasculogenic mimicry (VM) play important roles in the occurrence and development of tumors. However, the relationship between CAFs and VM formation, especially in gallbladder cancer (GBC) has not been clarified. In this study, we investigated whether gallbladder CAFs (GCAFs) can promote VM formation and tumor growth and explored the underlying molecular mechanism. Methods A co-culture system of human GBC cells and fibroblasts or HUVECs was established. VM formation, proliferation, invasion, migration, tube formation assays, CD31-PAS double staining, optic/electron microscopy and tumor xenograft assay were used to detect VM formation and malignant phenotypes of 3-D co-culture matrices in vitro, as well as the VM formation and tumor growth of xenografts in vivo, respectively. Microarray analysis was used to analyze gene expression profile in GCAFs/NFs and VM (+)/VM (−) in vitro. QRT-PCR, western blotting, IHC and CIF were used to detected NOX4 expression in GCAFs/NFs, 3-D culture/co-culture matrices in vitro, the xenografts in vivo and human gallbladder tissue/stroma samples. The correlation between NOX4 expression and clinicopathological and prognostic factors of GBC patients was analyzed. And, the underlying molecular mechanism of GCAFs promoting VM formation and tumor growth in GBC was explored. Results GCAFs promote VM formation and tumor growth in GBC; and the finding was confirmed by facts that GCAFs induced proliferation, invasion, migration and tube formation of GBC cells in vitro, and promoted VM formation and tumor growth of xenografts in vivo. NOX4 is highly expressed in GBC and its stroma, which is the key gene for VM formation, and is correlated with tumor aggression and survival of GBC patients. The GBC patients with high NOX4 expression in tumor cells and stroma have a poor prognosis. The underlying molecular mechanism may be related to the upregulation of NOX4 expression through paracrine IL-6 mediated IL-6/JAK/STAT3 signaling pathway. Conclusions GCAFs promote VM formation and tumor growth in GBC via upregulating NOX4 expression through the activation of IL-6-JAK-STAT3 signal pathway. NOX4, as a VM-related gene in GBC, is overexpressed in GBC cells and GCAFs, which is related to aggression and unfavorable prognosis of GBC patients.


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