scholarly journals CVB3 VP1 interacts with MAT1 to inhibit cell proliferation by interfering with Cdk-activating kinase complex activity in CVB3-induced acute pancreatitis

2021 ◽  
Vol 17 (2) ◽  
pp. e1008992
Author(s):  
Hongxia Zhang ◽  
Lingbing Zeng ◽  
Qiong Liu ◽  
Guilin Jin ◽  
Jieyu Zhang ◽  
...  

Coxsackievirus B3 (CVB3) belongs to the genus Enterovirus of the family Picornaviridae and can cause acute acinar pancreatitis in adults. However, the molecular mechanisms of pathogenesis underlying CVB3-induced acute pancreatitis have remained unclear. In this study, we discovered that CVB3 capsid protein VP1 inhibited pancreatic cell proliferation and exerted strong cytopathic effects on HPAC cells. Through yeast two-hybrid, co-immunoprecipitation, and confocal microscopy, we show that Menage a trois 1 (MAT1), a subunit of the Cdk-Activating Kinase (CAK) complex involved in cell proliferation and transcription, is a novel interaction protein with CVB3 VP1. Moreover, CVB3 VP1 inhibited MAT1 accumulation and localization, thus interfering with its interaction with CDK7. Furthermore, CVB3 VP1 could suppress CAK complex enzymic phosphorylation activity towards RNA Pol II and CDK4/6, direct substrates of CAK. VP1 also suppresses phosphorylation of retinoblastoma protein (pRb), an indirect CAK substrate, especially at phospho-pRb Ser780 and phospho-pRb Ser807/811 residues, which are associated with cell proliferation. Finally, we present evidence using deletion mutants that the C-terminal domain (VP1-D8, 768-859aa) is the minimal VP1 region required for its interaction with MAT1, and furthermore, VP1-D8 alone was sufficient to arrest cells in G1/S phase as observed during CVB3 infection. Taken together, we demonstrate that CVB3 VP1 can inhibit CAK complex assembly and activity through direct interaction with MAT1, to block MAT1-mediated CAK-CDK4/6-Rb signaling, and ultimately suppress cell proliferation in pancreatic cells. These findings substantially extend our basic understanding of CVB3-mediated pancreatitis, providing strong candidates for strategic therapeutic targeting.

2020 ◽  
Author(s):  
Hongxia Zhang ◽  
Lingbing Zeng ◽  
Qiong Liu ◽  
Guilin Jin ◽  
Jieyu Zhang ◽  
...  

AbstractCoxsackievirus B3 (CVB3) belongs to the genus Enterovirus of the family Picornaviridae and can cause acute acinar pancreatitis in adults. However, the molecular mechanisms of pathogenesis underlying CVB3-induced acute pancreatitis have remained unclear. In this study, we discovered that CVB3 capsid protein VP1 inhibited pancreatic cell proliferation and exerted strong cytopathic effects on HPAC cells. Through yeast two-hybrid, co-immunoprecipitation, and confocal microscopy, we show that Menage a trois 1 (MAT1), a subunit of the Cdk-Activating Kinase (CAK) complex involved in cell proliferation and transcription, is a novel interaction protein with CVB3 VP1. Moreover, CVB3 VP1 inhibited MAT1 accumulation and localization, thus interfering with its interaction with CDK7. Furthermore, CVB3 VP1 could suppress CAK complex enzymic phosphorylation activity towards RNA Pol II and CDK4/6, direct substrates of CAK. VP1 also suppresses phosphorylation of retinoblastoma protein (pRb), an indirect CAK substrate, especially at phospho-pRb Ser780 and phospho-pRb Ser807/811 residues, which are associated with cell proliferation. Finally, we present evidence using deletion mutants that the C-terminal domain (VP1-D8, 768-859aa) is the minimal VP1 region required for its interaction with MAT1, and furthermore, VP1-D8 alone was sufficient to arrest cells in G1/S phase as observed during CVB3 infection. Taken together, we demonstrate that CVB3 VP1 can inhibit CAK complex assembly and activity through direct interaction with MAT1, to block MAT1-mediated CAK-CDK4/6-Rb signaling, and ultimately suppress cell proliferation in pancreatic cells. These findings substantially extend our basic understanding of CVB3-mediated pancreatitis, providing strong candidates for strategic therapeutic targeting.


2021 ◽  
Author(s):  
Ramesh Bhandari ◽  
Sun Gui Feng ◽  
Liu Ya ◽  
Bian Zhixuan ◽  
Pan Quihui ◽  
...  

Abstract Background: Hepatoblastoma is common hepatic tumors occurring children between 0 – 5 years. Accumulating studies has shown lncRNA potential role in distinct cancers progression and development including the hepatoblastoma. SnoRNA host gene 9 (SNHG9) is associated the progression of distinct human cancers but, it`s specific molecular mechanisms in hepatoblastoma not unknown. Methods:In this study, we estimated SNHG9 expression on hepatoblastoma tissue and cell lines by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR). Next, we downregulated and upregulated the SNHG9 expression in hepatoblastoma cell lines and then determined the cell proliferation (CCK-8), colony formation, cellular apoptosis activity. The dual luciferase reporter activity, RNA immunoprecipitation (RIP), biotin RNA pulls down and Spemann’s Pearson correlation coefficient assay were performed to establish the interaction between the SNHG9, WNt3a and miR-23a-5p. Xenograft in-vivo tumorgenicity test was performed to elucidate therole of SNHG9 hepatoblastoma in tumorigenesis. SNHG9 role in Cisplatin drugs resistance in hepatoblastoma was also determined. Results:SNHG9 was significantly upregulated in hepatoblastoma tissue and cell lines. SNHG9 overexpression on HUH6 & HepG2 resulted in a significant increase in cell proliferation and clonogeneic while SNHG9 knock down resulted in a sustained inhibition of cell proliferation and clonogenic activity. Dual luciferase activity, RNA immunoprecipitation and biotin pull down confirmed the direct interaction of miR-23a-5p with SNHG9. In Xenograft tumorgenicity test showed SNHG9 downregulation significantly reduced the tumor growth on mice. ROC and Kaplan-Meier analysis showed potential prognostic and diagnostic importance of SNHG9 in hepatoblastoma.Conclusion: We concluded that SNHG9/miR-23a-5p/Wnt3a axis promotes the progression hepatoblastoma tumor.


2019 ◽  
Vol 14 (2) ◽  
pp. 170-176 ◽  
Author(s):  
Jun-He Zhang ◽  
Hai-Bin Xia

Background:Esophageal Carcinoma (EC) is the eighth most common cancer worldwide. Numerous studies have highlighted a vital role of microRNAs (miRNAs) in the development of EC. However, the mechanism of microRNA (miRNA)-141 in Esophageal Squamous Cell Carcinoma (ESCC) remains unknown.Objective:In this study, we explored the effects of miRNA-141 on EC cell proliferation, apoptosis, xenograft tumour growth and their possible mechanisms.Methods :A lentivirus-vector-expressing miRNA-141 was constructed, and a TE-1 cell line of ESCC with a stable expression of miRNA-141 was transfected and screened. The miRNA-141 expression level was detected using qRT-PCR. Effects of miRNA-141 overexpression on cell proliferation and apoptosis were detected using MTT and flow cytometry, respectively. Using a dual-luciferase reporter assay, a direct interaction between miRNA-141 and the 3'-Untranslated Region (UTR) of YAP1 and SOX17 was confirmed. Tumour xenograft experiment in nude mice was used to detect the tumour growth, and the effects of miRNA-141 overexpression on YAP1 and SOX17 were analysed using Western blot.Results:We found that miRNA-141 was highly expressed in TE-1 cells, and miRNA-141 overexpression promoted cell proliferation and inhibited apoptosis. Moreover, the miRNA-141 group showed significantly increased tumour growth ability, luciferase activities and expression levels of YAP1 and SOX17 in the miRNA-141group were significantly down-regulated.Conclusion:miRNA-141 promotes cell proliferation and inhibits apoptosis in ESCC by downregulating the expression level of YAP1 and SOX17, indicating that miRNA-141 may be a potential molecular target for the treatment of ESCC.


2018 ◽  
Vol 18 (7) ◽  
pp. 1025-1031
Author(s):  
Cheng Luo ◽  
Di Wu ◽  
Meiling Chen ◽  
Wenhua Miao ◽  
Changfeng Xue ◽  
...  

Background: Different saponins from herbs have been used as tonic or functional foods, and for treatment of various diseases including cancers. Although clinical data has supported the function of these saponins, their underlying molecular mechanisms have not been well defined. Methods: With the simulated hypoxia created by 8 hours of Cu++ exposure and following 24 hour incubation with different concentration of saponins in HepG2 cells for MTT assay, migration and invasion assays, and for RT-PCR, and with each group of cells for immunofluorescence observation by confocal microscopy. Results: ZC-4 had the highest rate of inhibition of cell proliferation by MTT assay, and the highest inhibition of migration rate by in vitro scratch assay, while ZC-3 had the highest inhibition of invasion ratio by transwell assay. Under the same simulated hypoxia, the molecular mechanism of saponin function was conducted by measuring the gene expression of Hypoxia Inducible Factor (HIF)-1α through RT-PCR, in which ZC-3 showed a potent inhibition of gene HIF-1α. For the protein expression by immunofluorescence staining with confocal microscopy, HIF-1α was also inhibited by saponins, with the most potent one being ZC-4 after eight hours’ relatively hypoxia incubation. Conclusion: Saponins ZC-4 and ZC-3 have the potential to reduce HepG2 cell proliferation, migration and invasion caused by hypoxia through effectively inhibiting the gene and protein expression of HIF-1α directly and as antioxidant indirectly


2021 ◽  
Vol 12 (4) ◽  
Author(s):  
Chen-Hua Dong ◽  
Tao Jiang ◽  
Hang Yin ◽  
Hu Song ◽  
Yi Zhang ◽  
...  

AbstractColorectal cancer is the second common cause of death worldwide. Lamin B2 (LMNB2) is involved in chromatin remodeling and the rupture and reorganization of nuclear membrane during mitosis, which is necessary for eukaryotic cell proliferation. However, the role of LMNB2 in colorectal cancer (CRC) is poorly understood. This study explored the biological functions of LMNB2 in the progression of colorectal cancer and explored the possible molecular mechanisms. We found that LMNB2 was significantly upregulated in primary colorectal cancer tissues and cell lines, compared with paired non-cancerous tissues and normal colorectal epithelium. The high expression of LMNB2 in colorectal cancer tissues is significantly related to the clinicopathological characteristics of the patients and the shorter overall and disease-free cumulative survival. Functional analysis, including CCK8 cell proliferation test, EdU proliferation test, colony formation analysis, nude mouse xenograft, cell cycle, and apoptosis analysis showed that LMNB2 significantly promotes cell proliferation by promoting cell cycle progression in vivo and in vitro. In addition, gene set enrichment analysis, luciferase report analysis, and CHIP analysis showed that LMNB2 promotes cell proliferation by regulating the p21 promoter, whereas LMNB2 has no effect on cell apoptosis. In summary, these findings not only indicate that LMNB2 promotes the proliferation of colorectal cancer by regulating p21-mediated cell cycle progression, but also suggest the potential value of LMNB2 as a clinical prognostic marker and molecular therapy target.


2021 ◽  
pp. 1-9
Author(s):  
Huan Guo ◽  
Baozhen Zeng ◽  
Liqiong Wang ◽  
Chunlei Ge ◽  
Xianglin Zuo ◽  
...  

BACKGROUND: The incidence of lung cancer in Yunnan area ranks firstly in the world and underlying molecular mechanisms of lung cancer in Yunnan region are still unclear. We screened a novel potential oncogene CYP2S1 used mRNA microassay and bioinformation database. The function of CYP2S1 in lung cancer has not been reported. OBJECTIVE: To investigate the functions of CYP2S1 in lung cancer. METHODS: Immunohistochemistry and Real-time PCR were used to verify the expression of CYP2S1. Colony formation and Transwell assays were used to determine cell proliferation, invasion and migration. Xenograft assays were used to detected cell growth in vivo. RESULTS: CYP2S1 is significantly up-regulated in lung cancer tissues and cells. Knockdown CYP2S1 in lung cancer cells resulted in decrease cell proliferation, invasion and migration in vitro. Animal experiments showed downregulation of CYP2S1 inhibited lung cancer cell growth in vivo. GSEA analysis suggested that CYP2S1 played functions by regulating E2F targets and G2M checkpoint pathway which involved in cell cycle. Kaplan-Meier analysis indicated that patients with high CYP2S1 had markedly shorter event overall survival (OS) time. CONCLUSIONS: Our data demonstrate that CYP2S1 exerts tumor suppressor function in lung cancer. The high expression of CYP2S1 is an unfavorable prognostic marker for patient survival.


2006 ◽  
Vol 291 (5) ◽  
pp. G877-G884 ◽  
Author(s):  
Pau Sancho-Bru ◽  
Ramón Bataller ◽  
Jordi Colmenero ◽  
Xavier Gasull ◽  
Montserrat Moreno ◽  
...  

Catecholamines participate in the pathogenesis of portal hypertension and liver fibrosis through α1-adrenoceptors. However, the underlying cellular and molecular mechanisms are largely unknown. Here, we investigated the effects of norepinephrine (NE) on human hepatic stellate cells (HSC), which exert vasoactive, inflammatory, and fibrogenic actions in the injured liver. Adrenoceptor expression was assessed in human HSC by RT-PCR and immunocytochemistry. Intracellular Ca2+ concentration ([Ca2+]i) was studied in fura-2-loaded cells. Cell contraction was studied by assessing wrinkle formation and myosin light chain II (MLC II) phosphorylation. Cell proliferation and collagen-α1(I) expression were assessed by [3H]thymidine incorporation and quantitative PCR, respectively. NF-κB activation was assessed by luciferase reporter gene and p65 nuclear translocation. Chemokine secretion was assessed by ELISA. Normal human livers expressed α1A-adrenoceptors, which were markedly upregulated in livers with advanced fibrosis. Activated human HSC expressed α1A-adrenoceptors. NE induced multiple rapid [Ca2+]i oscillations (Ca2+ spikes). Prazosin (α1-blocker) completely prevented NE-induced Ca2+ spikes, whereas propranolol (nonspecific β-blocker) partially attenuated this effect. NE caused phosphorylation of MLC II and cell contraction. In contrast, NE did not affect cell proliferation or collagen-α1(I) expression. Importantly, NE stimulated the secretion of inflammatory chemokines (RANTES and interleukin-8) in a dose-dependent manner. Prazosin blocked NE-induced chemokine secretion. NE stimulated NF-κB activation. BAY 11-7082, a specific NF-κB inhibitor, blocked NE-induced chemokine secretion. We conclude that NE stimulates NF-κB and induces cell contraction and proinflammatory effects in human HSC. Catecholamines may participate in the pathogenesis of portal hypertension and liver fibrosis by targeting HSC.


2010 ◽  
Vol 344 (1-2) ◽  
pp. 81-89 ◽  
Author(s):  
Wei-Wen Kuo ◽  
Jing-Ru Weng ◽  
Chih-Yang Huang ◽  
Chang-Hai Tsai ◽  
Wei-Hung Liu ◽  
...  

Author(s):  
R.K. Schmidt-Ullrich ◽  
R. Mikkelsen ◽  
K. Valerie ◽  
D. Todd ◽  
B. Kavanagh ◽  
...  

QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Rowaida Mohammed Reda M. M Aboushahba ◽  
Fayda Ibrahim Abdel Motaleb ◽  
Ahmed Abdel Aziz Abou-Zeid ◽  
Enas Samir Nabil ◽  
Dalia Abdel-Wahab Mohamed ◽  
...  

ABSTRACT Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths world-wide. There is an increasing need for the identification of novel biomarkers/targets for early diagnosis and for the development of novel chemopreventive and therapeutic agents for CRC. Recently, MACF1 gene has emerged as a potential therapeutic target in cancer as it involved in processes critical for tumor cell proliferation, invasion and metastasis. It is suggested that MACF1 may function in cancers through Wnt signaling. MiR-34a is a well-known tumor suppressor miRNA.miR-34a targets MACF1 gene as a part of the wnt signaling pathway. In this study, 40 colonic tissues were collected from CRC patients (20) and control subjects (20). miR-34a-5p was assessed by real time PCR in all study groups. The results showed highly significant decrease (P < 0.01) in miR-34a relative expression in the CRC group (median RQ 0.13) when compared to the benign group (median RQ 5.3) and the healthy control group (median RQ 19.63). miR-34a mimic and inhibitor were transfected in CaCo-2 cell line and proliferation was assessed. The transfection of the cell line with miR-34a mimic decreased cell proliferation. Our study suggests that miR-34a-5p targets MACF1 gene as a part of the wnt signaling pathway leading to the involvement in the molecular mechanisms of CRC development and progression.


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