scholarly journals Praeruptorin B Mitigates the Metastatic Ability of Human Renal Carcinoma Cells through Targeting CTSC and CTSV Expression

2020 ◽  
Vol 21 (8) ◽  
pp. 2919
Author(s):  
Chia-Liang Lin ◽  
Tung-Wei Hung ◽  
Tsung-Ho Ying ◽  
Chi-Jui Lin ◽  
Yi-Hsien Hsieh ◽  
...  

Renal cell carcinoma (RCC) is the most common adult kidney cancer, and accounts for 85% of all cases of kidney cancers worldwide. Praeruptorin B (Pra-B) is a bioactive constituent of Peucedanum praeruptorum Dunn and exhibits several pharmacological activities, including potent antitumor effects. However, the anti-RCC effects of Pra-B and their underlying mechanisms are unclear; therefore, we explored the effects of Pra-B on RCC cells in this study. We found that Pra-B nonsignificantly influenced the cell viability of human RCC cell lines 786-O and ACHN at a dose of less than 30 μM for 24 h treatment. Further study revealed that Pra-B potently inhibited the migration and invasion of 786-O and ACHN cells, as well as downregulated the mRNA and protein expression of cathepsin C (CTSC) and cathepsin V (CTSV) of 786-O and ACHN cells. Mechanistically, Pra-B also reduced the protein levels of phospho (p)-epidermal growth factor receptor (EGFR), p-mitogen-activated protein kinase kinase (MEK), and p-extracellular signal-regulated kinases (ERK) in RCC cells. In addition, Pra-B treatment inhibited the effect of EGF on the upregulation of EGFR–MEK–ERK, CTSC and CTSV expression, cellular migration, and invasion of 786-O cells. Our findings are the first to demonstrate that Pra-B can reduce the migration and invasion ability of human RCC cells through suppressing the EGFR-MEK-ERK signaling pathway and subsequently downregulating CTSC and CTSV. This evidence suggests that Pra-B can be developed as an effective antimetastatic agent for the treatment of RCC.

2012 ◽  
Vol 40 (1) ◽  
pp. 251-256 ◽  
Author(s):  
Pamela A. Lochhead ◽  
Rebecca Gilley ◽  
Simon J. Cook

The MEK5 [MAPK (mitogen-activated protein kinase)/ERK (extracellular-signal-regulated kinase) kinase 5]/ERK5 pathway is the least well studied MAPK signalling module. It has been proposed to play a role in the pathology of cancer. In the present paper, we review the role of the MEK5/ERK5 pathway using the ‘hallmarks of cancer’ as a framework and consider how this pathway is deregulated. As well as playing a key role in endothelial cell survival and tubular morphogenesis during tumour neovascularization, ERK5 is also emerging as a regulator of tumour cell invasion and migration. Several oncogenes can stimulate ERK5 activity, and protein levels are increased by a novel amplification at chromosome locus 17p11 and by down-regulation of the microRNAs miR-143 and miR-145. Together, these finding underscore the case for further investigation into understanding the role of ERK5 in cancer.


2015 ◽  
Vol 33 (6) ◽  
pp. 771-779 ◽  
Author(s):  
Naoshi Nishida ◽  
Masayuki Kitano ◽  
Toshiharu Sakurai ◽  
Masatoshi Kudo

Hepatocellular carcinoma (HCC) is the second leading cause of cancer death worldwide, and prognosis remains unsatisfactory when the disease is diagnosed at an advanced stage. Many molecular targeted agents are being developed for the treatment of advanced HCC; however, the only promising drug to have been developed is sorafenib, which acts as a multi-kinase inhibitor. Unfortunately, a subgroup of HCC is resistant to sorafenib, and the majority of these HCC patients show disease progression even after an initial satisfactory response. To date, a number of studies have examined the underlying mechanisms involved in the response to sorafenib, and trials have been performed to overcome the acquisition of drug resistance. The anti-tumor activity of sorafenib is largely attributed to the blockade of the signals from growth factors, such as vascular endothelial growth factor receptor and platelet-derived growth factor receptor, and the downstream RAF/mitogen-activated protein/extracellular signal-regulated kinase (ERK) kinase (MEK)/ERK cascade. The activation of an escape pathway from RAF/MEK/ERK possibly results in chemoresistance. In addition, there are several features of HCCs indicating sorafenib resistance, such as epithelial-mesenchymal transition and positive stem cell markers. Here, we review the recent reports and focus on the mechanism and prediction of chemoresistance to sorafenib in HCC.


Blood ◽  
2005 ◽  
Vol 106 (10) ◽  
pp. 3423-3431 ◽  
Author(s):  
Ahmad Salameh ◽  
Federico Galvagni ◽  
Monia Bardelli ◽  
Federico Bussolino ◽  
Salvatore Oliviero

AbstractVascular endothelial growth factor receptor-3 (VEGFR-3) plays a key role for the remodeling of the primary capillary plexus in the embryo and contributes to angiogenesis and lymphangiogenesis in the adult. However, VEGFR-3 signal transduction pathways remain to be elucidated. Here we investigated VEGFR-3 signaling in primary human umbilical vein endothelial cells (HUVECs) by the systematic mutation of the tyrosine residues potentially involved in VEGFR-3 signaling and identified the tyrosines critical for its function. Y1068 was shown to be essential for the kinase activity of the receptor. Y1063 signals the receptor-mediated survival by recruiting CRKI/II to the activated receptor, inducing a signaling cascade that, via mitogen-activated protein kinase kinase-4 (MKK4), activates c-Jun N-terminal kinase-1/2 (JNK1/2). Inhibition of JNK1/2 function either by specific peptide inhibitor JNKI1 or by RNA interference (RNAi) demonstrated that activation of JNK1/2 is required for a VEGFR-3–dependent prosurvival signaling. Y1230/Y1231 contributes, together with Y1337, to proliferation, migration, and survival of endothelial cells. Phospho-Y1230/Y1231 directly recruits growth factor receptor–bonus protein (GRB2) to the receptor, inducing the activation of both AKT and extracellular signal–related kinase 1/2 (ERK1/2) signaling. Finally, we observed that Y1063 and Y1230/Y1231 signaling converge to induce c-JUN expression, and RNAi experiments demonstrated that c-JUN is required for growth factor–induced prosurvival signaling in primary endothelial cells.


2019 ◽  
Vol 20 (19) ◽  
pp. 4779 ◽  
Author(s):  
Jeanne K. DuShane ◽  
Colleen L. Mayberry ◽  
Michael P. Wilczek ◽  
Sarah L. Nichols ◽  
Melissa S. Maginnis

JC polyomavirus (JCPyV), a ubiquitous human pathogen, is the etiological agent of the fatal neurodegenerative disease progressive multifocal leukoencephalopathy (PML). Like most viruses, JCPyV infection requires the activation of host-cell signaling pathways in order to promote viral replication processes. Previous works have established the necessity of the extracellular signal-regulated kinase (ERK), the terminal core kinase of the mitogen-activated protein kinase (MAPK) cascade (MAPK-ERK) for facilitating transcription of the JCPyV genome. However, the underlying mechanisms by which the MAPK-ERK pathway becomes activated and induces viral transcription are poorly understood. Treatment of cells with siRNAs specific for Raf and MAP kinase kinase (MEK) targets proteins in the MAPK-ERK cascade, significantly reducing JCPyV infection. MEK, the dual-specificity kinase responsible for the phosphorylation of ERK, is phosphorylated at times congruent with early events in the virus infectious cycle. Moreover, a MAPK-specific signaling array revealed that transcription factors downstream of the MAPK cascade, including cMyc and SMAD4, are upregulated within infected cells. Confocal microscopy analysis demonstrated that cMyc and SMAD4 shuttle to the nucleus during infection, and nuclear localization is reduced when ERK is inhibited. These findings suggest that JCPyV induction of the MAPK-ERK pathway is mediated by Raf and MEK and leads to the activation of downstream transcription factors during infection. This study further defines the role of the MAPK cascade during JCPyV infection and the downstream signaling consequences, illuminating kinases as potential therapeutic targets for viral infection.


2002 ◽  
Vol 283 (4) ◽  
pp. H1673-H1680 ◽  
Author(s):  
Rebecca W. Carter ◽  
Nancy L. Kanagy

We have demonstrated enhanced contractile sensitivity to the α2-adrenoreceptor (α2-AR) agonist UK-14304 in arteries from rats made hypertensive with chronic nitric oxide synthase (NOS) inhibition (LHR) compared with arteries from normotensive rats (NR); additionally, this contraction requires Ca2+ entry. We hypothesized that tyrosine kinases augment α2-AR contraction in LHR arteries by increasing Ca2+. The tyrosine kinase inhibitor tyrphostin 23 significantly attenuated UK-14304 contraction of denuded thoracic aortic rings from NR and LHR. However, tyrphostin 23 did not alter UK-14304 contraction in ionomycin-permeabilized aorta, which indicates that tyrosine kinases regulate intracellular Ca2+concentration. The Src family inhibitor PP1 and the epidermal growth factor receptor kinase inhibitor AG-1478 did not alter α2-AR contraction, whereas the mitogen-activated protein kinase extracellular signal-regulated kinase kinase inhibitor PD-98059 attenuated the contraction. Contraction to CaCl2 in ionomycin-permeabilized LHR rings was greater than in NR rings. UK-14304 augmented CaCl2 contraction in ionomycin-permeabilized rings from both groups but to a greater extent in LHR aorta. Together, these data suggest that α2-AR stimulates contraction via two pathways. One, which is enhanced with NOS inhibition hypertension, activates Ca2+ sensitivity and is independent of tyrosine kinases. The other is tyrosine kinase dependent and regulates intracellular Ca2+ concentration.


2017 ◽  
Vol 43 (5) ◽  
pp. 1974-1986 ◽  
Author(s):  
Ximing Wang ◽  
Yanxia Zhang ◽  
Hongshan Wang ◽  
Genshang Zhao ◽  
Xianen Fa

Background/Aims: Myocardial infarction (MI) is a leading cause of morbidity and mortality. Here, we sought to explore the potential role and underlying mechanism of miR-145 in MI. Methods: H9c2 cells were cultured under persistent hypoxia to simulate MI. The hypoxia-induced injury was assessed on the basis of cell viability, migration, invasion and apoptosis. The expression of miR-145 was evaluated by qRT-PCR and the influence of aberrantly expressed miR-145 on H9c2 cells under hypoxia was also estimated. Utilizing bioinformatics methods, the target genes of miR-145 were verified by luciferase reporter assay. Then, effects of abnormally expressed target gene on miR-145 silenced H9c2 cells were assessed. Finally, the phosphorylation levels of key kinases in the phosphatidylinositol-3-kinase (PI3K)/AKT and the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathways were detected by Western blot analysis. Results: Hypoxia remarkably lowered viability, migration and invasion but promoted cell apoptosis. Meantime, the miR-145 level was up-regulated in H9c2 cells under hypoxia. Following experiments suggested that hypoxia-induced injury was exacerbated by miR-145 overexpression while was alleviated by miR-145 silence. Rac1 was predicted and further validated to be a target gene of miR-145. The influence of miR-145 silencing on H9c2 cells under hypoxia could be reversed by down-regulation of Rac1. Additionally, the phosphorylation levels of PI3K, AKT, MAPK and ERK were all elevated in miR-145 silenced cells and these alterations were reversed by down-regulation of Rac1. Conclusion: miR-145 silencing could protect H9c2 cells against hypoxia-induced injury by targeting Rac1, in which PI3K/AKT and MAPK/ERK pathways might be involved.


2005 ◽  
Vol 25 (9) ◽  
pp. 1159-1170 ◽  
Author(s):  
Ibolya E András ◽  
Hong Pu ◽  
Jing Tian ◽  
Mária A Deli ◽  
Avindra Nath ◽  
...  

Exposure of brain microvascular endothelial cells (BMEC) to human immunodeficiency virus-1 (HIV-1) Tat protein can decrease expression and change distribution of tight junction proteins, including claudin-5. Owing to the importance of claudin-5 in maintaining the blood–brain barrier (BBB) integrity, the present study focused on the regulatory mechanisms of Tat-induced alterations of claudin-5 mRNA and protein levels. Real-time reverse-transcription-polymerase chain reaction revealed that claudin-5 mRNA was markedly diminished in BMEC exposed to Tat. However, U0126 (an inhibitor of mitogen-activated protein kinase kinase1/2, MEK1/2) protected against this effect. In addition, inhibition of the vascular endothelial growth factor receptor type 2 (VEGFR-2) by SU1498, phosphatidylinositol-3 kinase (PI-3 K) by LY294002, nuclear factor-κB (NF-κB) by peptide SN50, and intracellular calcium by BAPTA/AM partially prevented Tat-mediated alterations in claudin-5 protein levels and immunoreactivity patterns. In contrast, inhibition of protein kinase C did not affect claudin-5 expression in Tat-treated cells. The present findings indicate that activation of VEGFR-2 and multiple redox-regulated signal transduction pathways are involved in Tat-induced alterations of claudin-5 expression. Because claudins constitute the major backbone of tight junctions, the present data are relevant to the disturbances of the BBB in the course of HIV-1 infection.


Author(s):  
Anthony Russo ◽  
Albert Mensah ◽  
Judith Bowman

Autism spectrum disorders (ASDs) are complex, highly heritable neurodevelopmental disorders affecting ∼1 in 60-100 children. The extracellular signal-regulated kinases, ERK1 and ERK2, are central elements of one of the most prominent intracellular signaling cascades, the mitogen activated protein kinase (MAPK) pathway. They are genetically linked to ASDs and other syndromes typified by intellectual disability. In this study, we measured the concentration of phosphorylated (activated) ERK 1 and 2. We present evidence that ERK is decreased in individuals with autism, and that ERK levels are associated with decreased Epidermal Growth Factor Receptor (EGFR).


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