scholarly journals Chemotherapy-induced miR-141/MAP4K4 signaling suppresses progression of colorectal cancer

2018 ◽  
Vol 38 (6) ◽  
Author(s):  
Feifei Wang ◽  
Lianmei Zhao ◽  
Juan Zhang ◽  
Zesong Meng ◽  
Chaoxi Zhou ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Mitogen Activated Protein Kinase ◽  
Chemotherapy Drugs ◽  
Reverse Transcription Quantitative Pcr ◽  
Mitogen Activated Protein ◽  
Resistance To Chemotherapy ◽  
Protein Kinase Kinase

One of the treatment failures for colorectal cancer (CRC) is resistance to chemotherapy drugs. miRNAs have been demonstrated to be a new regulator of pathobiological processes in various tumors. While few studies have explored the specific role of miR-141 in mediating 5-fluorouracil (5-FU) sensitivity of CRC cells, the present study aimed to detect the contribution of miR-141 in 5-FU sensitivity. The CRC cells viability was measured by MTS assay and cell colony forming. The expression of miR-141 and its downstream targets were assessed by reverse transcription quantitative PCR, Western blotting, and immunohistochemistry. The functional assays were conducted using CRC cells and nude mice. At the present study, we found overexpression of miR-141 could inhibit proliferation, migration, tumor-forming and invasive potential of CRC cells in vitro and mitogen-activated protein kinase kinase kinase kinase 4 (MAP4K4) was verified as a directed target of miR-141. The combination treatment of miR-141 with 5-FU, directly targetting MAP4K4, could better inhibit invasion and metastasis of CRC cells colony than either one alone. Furthermore, overexpression of miR-141, targetting MAP4K4, enhanced the effected of 5-FU and suppressed the malignant biological behaviors, in vivo. Our findings showed that 5-FU inhibited malignant behavior of human CRC cells in vitro and in vivo by enhancing the efficiency of miR-141. Our data suggested that targetting the miR-141/MAP4K4 signaling pathway could be a potential molecular target that may enhance chemotherapeutic efficacy in the treatment of CRC.

scholarly journals Mitogen-activated protein kinase kinase 1 (MKK1) is negatively regulated by threonine phosphorylation

1994 ◽  
Vol 14 (3) ◽  
pp. 1594-1602
Author(s):  
A J Rossomando ◽  
P Dent ◽  
T W Sturgill ◽  
D R Marshak
Keyword(s):  
Protein Kinase ◽  
Phosphorylation Site ◽  
Mitogen Activated Protein Kinase ◽  
Dual Specificity ◽  
Mitogen Activated Protein ◽  
Kinase Cascade ◽  
Protein Kinase Cascade ◽  
Protein Kinase Kinase

Mitogen-activated protein kinase kinase 1 (MKK1), a dual-specificity tyrosine/threonine protein kinase, has been shown to be phosphorylated and activated by the raf oncogene product as part of the mitogen-activated protein kinase cascade. Here we report the phosphorylation and inactivation of MKK1 by phosphorylation on threonine 286 and threonine 292. MKK1 contains a consensus phosphorylation site for p34cdc2, a serine/threonine protein kinase that regulates the cell division cycle, at Thr-286 and a related site at Thr-292. p34cdc2 catalyzes the in vitro phosphorylation of MKK1 on both of these threonine residues and inactivates MKK1 enzymatic activity. Both sites are phosphorylated in vivo as well. The data presented in this report provide evidence that MKK1 is negatively regulated by threonine phosphorylation.

scholarly journals Role of Muramyl Dipeptide in Lipopolysaccharide-Mediated Biological Activity and Osteoclast Activity

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Hideki Kitaura ◽  
Masahiko Ishida ◽  
Keisuke Kimura ◽  
Haruki Sugisawa ◽  
Akiko Kishikawa ◽  
...  
Keyword(s):  
Biological Activities ◽  
Muramyl Dipeptide ◽  
Mapk Signaling ◽  
Osteoclast Formation ◽  
Mitogen Activated Protein Kinase ◽  
Immunological Activity ◽  
Mitogen Activated Protein

Lipopolysaccharide (LPS) is an endotoxin and bacterial cell wall component that is capable of inducing inflammation and immunological activity. Muramyl dipeptide (MDP), the minimal essential structural unit responsible for the immunological activity of peptidoglycans, is another inflammation-inducing molecule that is ubiquitously expressed by bacteria. Several studies have shown that inflammation-related biological activities were synergistically induced by interactions between LPS and MDP. MDP synergistically enhances production of proinflammatory cytokines that are induced by LPS exposure. Injection of MDP induces lethal shock in mice challenged with LPS. LPS also induces osteoclast formation and pathological bone resorption; MDP enhances LPS induction of both processes. Furthermore, MDP enhances the LPS-induced receptor activator of NF-κB ligand (RANKL) expression and toll-like receptor 4 (TLR4) expression bothin vivoandin vitro. Additionally, MDP enhances LPS-induced mitogen-activated protein kinase (MAPK) signaling in stromal cells. Taken together, these findings suggest that MDP plays an important role in LPS-induced biological activities. This review discusses the role of MDP in LPS-mediated biological activities, primarily in relation to osteoclastogenesis.

scholarly journals The Ebola virus soluble glycoprotein contributes to viral pathogenesis by activating the MAP kinase signaling pathway

2021 ◽  
Vol 17 (9) ◽  
pp. e1009937
Author(s):  
Wakako Furuyama ◽  
Kyle Shifflett ◽  
Heinz Feldmann ◽  
Andrea Marzi
Keyword(s):  
Signaling Pathway ◽  
Ebola Virus ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Hek293 Cells ◽  
Huh7 Cells ◽  
Mitogen Activated Protein

Ebola virus (EBOV) expresses three different glycoproteins (GPs) from its GP gene. The primary product, soluble GP (sGP), is secreted in abundance during infection. EBOV sGP has been discussed as a potential pathogenicity factor, however, little is known regarding its functional role. Here, we analyzed the role of sGP in vitro and in vivo. We show that EBOV sGP has two different functions that contribute to infectivity in tissue culture. EBOV sGP increases the uptake of virus particles into late endosomes in HEK293 cells, and it activates the mitogen-activated protein kinase (MAPK) signaling pathway leading to increased viral replication in Huh7 cells. Furthermore, we analyzed the role of EBOV sGP on pathogenicity using a well-established mouse model. We found an sGP-dependent significant titer increase of EBOV in the liver of infected animals. These results provide new mechanistic insights into EBOV pathogenicity and highlight EBOV sGP as a possible therapeutic target.

MRP8 and MRP14 control microtubule reorganization during transendothelial migration of phagocytes

Blood ◽  
2004 ◽  
Vol 104 (13) ◽  
pp. 4260-4268 ◽  
Author(s):  
Thomas Vogl ◽  
Stephan Ludwig ◽  
Matthias Goebeler ◽  
Anke Strey ◽  
Irmgard S. Thorey ◽  
...  
Keyword(s):  
Calcium Binding ◽  
S100 Protein ◽  
Transendothelial Migration ◽  
Mitogen Activated Protein Kinase ◽  
Binding Partner ◽  
Calcium Dependent ◽  
Mitogen Activated Protein

Abstract MRP14 (S100A9) is the major calcium-binding protein of neutrophils and monocytes. Targeted gene disruption reveals an essential role of this S100 protein for transendothelial migration of phagocytes. The underlying molecular mechanism comprises major alterations of cytoskeletal metabolism. MRP14, in complex with its binding partner MRP8 (S100A8), promotes polymerization of microtubules. MRP14 is specifically phosphorylated by p38 mitogen-activated protein kinase (MAPK). This phosphorylation inhibits MRP8/MRP14-induced tubulin polymerization. Phosphorylation of MRP14 is antagonistically regulated by binding of MRP8 and calcium. The biologic relevance of these findings is confirmed by the fact that MAPK p38 fails to stimulate migration of MRP14-/- granulocytes in vitro and MRP14-/- mice show a diminished recruitment of granulocytes into the granulation tissue during wound healing in vivo. MRP14-/- granulocytes contain significantly less polymerized tubulin, which subsequently results in minor activation of Rac1 and Cdc42 after stimulation of p38 MAPK. Thus, the complex of MRP8/MRP14 is the first characterized molecular target integrating MAPK- and calcium-dependent signals during migration of phagocytes.

CDKN2B antisense RNA 1 suppresses tumor growth in human colorectal cancer by targeting MAPK inactivator dual-specificity phosphatase 1

2021 ◽  
Author(s):  
Jie Pan ◽  
Mengxin Lin ◽  
Zongbin Xu ◽  
Meifang Xu ◽  
Junrong Zhang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Cell Proliferation ◽  
Protein Kinase ◽  
Antisense Rna ◽  
Mitogen Activated Protein Kinase ◽  
Human Colorectal Cancer ◽  
Dual Specificity ◽  
Mitogen Activated Protein

Abstract Aberrant expression of long noncoding RNA cyclin-dependent kinase inhibitor 2B antisense RNA 1 (CDKN2B-AS1) has been detected in human colorectal cancer (CRC). This study aimed to investigate the role of CDKN2B-AS1 and the underlying mechanism in human CRC. Gain- and loss-of-function assays were performed to explore the role of CDKN2B-AS1 in the malignant behavior of HCT116 and SW480 CRC cells in vitro and in vivo. RNA pull-down assay was conducted to identify the target of CDKN2B-AS1 in CRC cells. The physical and functional interactions between CDKN2B-AS1 and the target were examined. CDKN2B-AS1 inhibited CRC cell proliferation and migration while promoting apoptosis in vitro via activation of mitogen-activated protein kinase kinases (MEK)/extracellular signal-regulated kinase (ERK)/p38 signaling. CDKN2B-AS1 bound to mitogen-activated protein kinase (MAPK) inactivator dual-specificity phosphatase 1 (DUSP1) in CRC cells. In contrast to CDKN2B-AS1, DUSP1 promoted CRC cell proliferation, suppressed apoptosis and inactivated MEK/ERK/p38 signaling in CRC cells. Furthermore, CDKN2B-AS1 overexpression attenuated DUSP1 expression in normal colonic myofibroblasts and CRC cells. Overexpression of DUSP1 effectively countered the activation of MEK/ERK/p38 signaling induced by CDKN2B-AS1 overexpression or further blocked MEK/ERK/p38 signaling suppressed by CDKN2B-AS1 silencing. In the mouse xenograft model, CDKN2B-AS1 suppressed CRC growth, whereas DUSP1 promoted CRC growth. CDKN2B-AS1 induced cell apoptosis while suppressing EMT (epithelial–mesenchymal transition), whereas DUSP1 suppressed cell apoptosis while inducing EMT in CRC, as evidenced by the alterations in the protein levels of apoptosis and EMT markers in tumor tissue samples. CDKN2B-AS1 regulates CRC cell growth and survival by targeting MAPK inactivator DUSP1.

scholarly journals Mitotic Phosphorylation of Golgi Reassembly Stacking Protein 55 by Mitogen-activated Protein Kinase ERK2

2001 ◽  
Vol 12 (6) ◽  
pp. 1811-1817 ◽  
Author(s):  
Stephen A. Jesch ◽  
Timothy S. Lewis ◽  
Natalie G. Ahn ◽  
Adam D. Linstedt
Keyword(s):  
Protein Kinase ◽  
Specific Inhibitor ◽  
Mitogen Activated Protein Kinase ◽  
Erk Pathway ◽  
Erk Activation ◽  
Mitogen Activated Protein ◽  
Mitotic Phosphorylation

The role of the mitogen-activated protein kinase kinase (MKK)/extracellular-activated protein kinase (ERK) pathway in mitotic Golgi disassembly is controversial, in part because Golgi-localized targets have not been identified. We observed that Golgi reassembly stacking protein 55 (GRASP55) was phosphorylated in mitotic cells and extracts, generating a mitosis-specific phospho-epitope recognized by the MPM2 mAb. This phosphorylation was prevented by mutation of ERK consensus sites in GRASP55. GRASP55 mitotic phosphorylation was significantly reduced, both in vitro and in vivo, by treatment with U0126, a potent and specific inhibitor of MKK and thus ERK activation. Furthermore, ERK2 directly phosphorylated GRASP55 on the same residues that generated the MPM2 phospho-epitope. These results are the first demonstration of GRASP55 mitotic phosphorylation and indicate that the MKK/ERK pathway directly phosphorylates the Golgi during mitosis.

scholarly journals Synergistic activation of stress-activated protein kinase 1/c-Jun N-terminal kinase (SAPK1/JNK) isoforms by mitogen-activated protein kinase kinase 4 (MKK4) and MKK7

2000 ◽  
Vol 352 (1) ◽  
pp. 145-154 ◽  
Author(s):  
Yvonne FLEMING ◽  
Christopher G. ARMSTRONG ◽  
Nick MORRICE ◽  
Andrew PATERSON ◽  
Michel GOEDERT ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Specific Protein ◽  
Mitogen Activated Protein Kinase ◽  
Tyrosine Residue ◽  
Hek 293 ◽  
Mitogen Activated Protein ◽  
Jnk Isoforms ◽  
Protein Kinase Kinase

Stress-activated protein kinase 1 (SAPK1), also called c-Jun N-terminal kinase (JNK), becomes activated in vivo in response to pro-inflammatory cytokines or cellular stresses. Its full activation requires the phosphorylation of a threonine and a tyrosine residue in a Thr-Pro-Tyr motif, which can be catalysed by the protein kinases mitogen-activated protein kinase kinase (MKK)4 and MKK7. Here we report that MKK4 shows a striking preference for the tyrosine residue (Tyr-185), and MKK7 a striking preference for the threonine residue (Thr-183) in three SAPK1/JNK1 isoforms tested (JNK1α1, JNK2α2 and JNK3α1). For this reason, MKK4 and MKK7 together produce a synergistic increase in the activity of each SAPK1/JNK isoform in vitro. The MKK7β variant, which is several hundred-fold more efficient in activating all three SAPK1/JNK isoforms than is MKK7α´, is equally specific for Thr-183. MKK7 also phosphorylates JNK2α2 at Thr-404 and Ser-407 in vitro, Ser-407 being phosphorylated much more rapidly than Thr-183 in vitro. Thr-404/Ser-407 are phosphorylated in unstimulated human KB cells and HEK-293 cells, and phosphorylation is increased in response to an osmotic stress (0.5M sorbitol). However, in contrast with Thr-183 and Tyr-185, the phosphorylation of Thr-404 and Ser-407 is not increased in response to other agonists that activate MKK7 and SAPK1/JNK, suggesting that phosphorylation of these residues is catalysed by another protein kinase, such as CK2, which also phosphorylates Thr-404 and Ser-407 in vitro. MKK3, MKK4 and MKK6 all show a strong preference for phosphorylation of the tyrosine residue of the Thr-Gly-Tyr motifs in their known substrates SAPK2a/p38, SAPK3/p38γ and SAPK4/p38δ. MKK7 also phosphorylates SAPK2a/p38 at a low rate (but not SAPK3/p38γ or SAPK4/p38δ), and phosphorylation occurs exclusively at the tyrosine residue, demonstrating that MKK7 is intrinsically a ‘dual-specific’ protein kinase.

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