scholarly journals The miR-361-3p increases enzalutamide (Enz) sensitivity via targeting the ARv7 and MKNK2 to better suppress the Enz-resistant prostate cancer

2020 ◽  
Vol 11 (9) ◽  
Author(s):  
Bianjiang Liu ◽  
Yin Sun ◽  
Min Tang ◽  
Chao Liang ◽  
Chi-Ping Huang ◽  
...  

Abstract The androgen receptor splicing variant 7 (ARv7) that lacks the ligand-binding domain is increasingly considered as a key player leading to enzalutamide (Enz) resistance in patients with prostate cancer (PCa). However, the detailed mechanisms of how ARv7 expression is regulated and whether it also needs other factors to induce maximal Enz resistance remain unclear. Here, we identified a microRNA, miR-361-3p, whose expression is lower in patients with recurrent PCa, could function via binding to the 3′UTR of ARv7, but not the wild type of AR, to suppress its expression to increase the Enz sensitivity. Importantly, we found that miR-361-3p could also bind to the 3′UTR of MAP kinase-interacting serine/threonine kinase 2 (MKNK2) to suppress its expression to further increase the Enz sensitivity. In turn, the increased Enz can then function via a feedback mechanism through altering the HIF-2α/VEGFA signaling to suppress the expression of miR-361-3p under hypoxia conditions. Preclinical studies using an in vivo mouse model with orthotopically xenografted CWR22Rv1 cells demonstrated that combining the Enz with the small molecule miR-361-3p would result in better suppression of the Enz-resistant PCa tumor progression. Together, these preclinical studies demonstrate that miR-361-3p can function via suppressing the expression of ARv7 and MKNK2 to maximally increase the Enz sensitivity, and targeting these newly identified Enz/miR-361-3p/ARv7 and/or Enz/miR-361-3p/MKNK2 signals with small molecules may help in the development of novel therapies to better suppress the CRPC in patients that already have developed the Enz resistance.

2020 ◽  
Vol 11 (11) ◽  
Author(s):  
Fu-Ju Chou ◽  
ChangYi Lin ◽  
Hao Tian ◽  
WanYing Lin ◽  
Bosen You ◽  
...  

Abstract The FDA-approved anti-androgen Enzalutamide (Enz) has been used successfully as the last line therapy to extend castration-resistant prostate cancer (CRPC) patients’ survival by an extra 4.8 months. However, CRPC patients eventually develop Enz-resistance that may involve the induction of the androgen receptor (AR) splicing variant ARv7. Here we found that Cisplatin (Cis) or Carboplatin, currently used in chemotherapy/radiation therapy to suppress tumor progression, could restore the Enz sensitivity in multiple Enz-resistant (EnzR) CRPC cells via directly degrading/suppressing the ARv7. Combining Cis or Carboplatin with Enz therapy can also delay the development of Enz-resistance in CRPC C4-2 cells. Mechanism dissection found that Cis or Carboplatin might decrease the ARv7 expression via multiple mechanisms including targeting the lncRNA-Malat1/SF2 RNA splicing complex and increasing ARv7 degradation via altering ubiquitination. Preclinical studies using in vivo mouse model with implanted EnzR1-C4-2 cells also demonstrated that Cis plus Enz therapy resulted in better suppression of EnzR CRPC progression than Enz treatment alone. These results not only unveil the previously unrecognized Cis mechanism to degrade ARv7 via targeting the Malat1/SF2 complex and ubiquitination signals, it may also provide a novel and ready therapy to further suppress the EnzR CRPC progression in the near future.


1996 ◽  
Vol 16 (3) ◽  
pp. 998-1005 ◽  
Author(s):  
J Liu ◽  
Y Wu ◽  
G Z Ma ◽  
D Lu ◽  
L Haataja ◽  
...  

The first exon of the BCR gene encodes a new serine/threonine protein kinase. Abnormal fusion of the BCR and ABL genes, resulting from the formation of the Philadelphia chromosome (Ph), is the hallmark of Ph-positive leukemia. We have previously demonstrated that the Bcr protein is tyrosine phosphorylated within first-exon sequences by the Bcr-Abl oncoprotein. Here we report that in addition to tyrose 177 (Y-177), Y-360 and Y283 are phosphorylated in Bcr-Abl proteins in vitro. Moreover, Bcr tyrosine 360 is phosphorylated in vivo within both Bcr-Abl and Bcr. Bcr mutant Y177F had a greatly reduced ability to transphosphorylate casein and histone H1, whereas Bcr mutants Y177F and Y283F had wild-type activities. In contrast, the Y360F mutation had little effect on Bcr's autophosphorylation activity. Tyrosine-phosphorylated Bcr, phosphorylated in vitro by Bcr-Abl, was greatly inhibited in its serine/threonine kinase activity, impairing both auto- and transkinase activities of Bcr. Similarly, the isolation of Bcr from cells expressing Bcr-Abl under conditions that preserve phosphotyrosine residues also reduced Bcr's kinase activity. These results indicate that tyrosine 360 of Bcr is critical for the transphosphorylation activity of Bcr and that in Ph-positive leukemia, Bcr serine/threonine kinase activity is seriously impaired.


Cancers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 3201
Author(s):  
Laura V Bownes ◽  
Adele P Williams ◽  
Raoud Marayati ◽  
Colin H Quinn ◽  
Sara C Hutchins ◽  
...  

Background: Serine-threonine kinase receptor-associated protein (STRAP) plays an important role in neural development but also in tumor growth. Neuroblastoma, a tumor of neural crest origin, is the most common extracranial solid malignancy of childhood and it continues to carry a poor prognosis. The recent discovery of the role of STRAP in another pediatric solid tumor, osteosarcoma, and the known function of STRAP in neural development, led us to investigate the role of STRAP in neuroblastoma tumorigenesis. Methods: STRAP protein expression was abrogated in two human neuroblastoma cell lines, SK-N-AS and SK-N-BE(2), using transient knockdown with siRNA, stable knockdown with shRNA lentiviral transfection, and CRISPR-Cas9 genetic knockout. STRAP knockdown and knockout cells were examined for phenotypic alterations in vitro and tumor growth in vivo. Results: Cell proliferation, motility, and growth were significantly decreased in STRAP knockout compared to wild-type cells. Indicators of stemness, including mRNA abundance of common stem cell markers Oct4, Nanog, and Nestin, the percentage of cells expressing CD133 on their surface, and the ability to form tumorspheres were significantly decreased in the STRAP KO cells. In vivo, STRAP knockout cells formed tumors less readily than wild-type tumor cells. Conclusion: These novel findings demonstrated that STRAP plays a role in tumorigenesis and maintenance of neuroblastoma stemness.


2016 ◽  
Vol 8 (1) ◽  
pp. 12 ◽  
Author(s):  
Sung Hwa Shin ◽  
Eun Jeoung Lee ◽  
Sunghee Hyun ◽  
Dowonkyoung Park ◽  
Sang Sun Kang

Uncoordinated 51-like kinase 2 (ULK2) is a member of the serine/threonine kinase family that functions an essential role regulating autophagy in mammalian cells. As autophagy is implicated in normal cellular homeostasis and multiple diseases, better mechanisticinsight will drive thedevelopment of novel therapeutic approaches. Here, we present evidence that ULK2 interacts withYAP for its degradation and subcellular localization. A potential PPxY motif (328PPnY331) was identified, which is similar with the consensus PPxY motif in ULK2 S/P domain. TheP329A (PA) mutation in the PY motif of ULK2 abolished the YAP-ULK2 association.At first, we observed that ULK2 physically interacted to YAP in vivo and in vitro, using a pull-down approach. Secondly, ULK2 and YAP co- localized at the apical (or tight junction) membrane as visualized by confocal microscopy. Furthermore, the PA mutant substantially increased during autophagy than that of wild-type ULK2 or the P242A mutant in transient transfection assays. Thus, the association between ULK2 and YAP through the WW domain links autophagy and the Hippo signal transduction pathway.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Russell J. Ledet ◽  
Sophie E. Ruff ◽  
Yu Wang ◽  
Shruti Nayak ◽  
Jeffrey A. Schneider ◽  
...  

AbstractPIM1 is a serine/threonine kinase that promotes and maintains prostate tumorigenesis. While PIM1 protein levels are elevated in prostate cancer relative to local disease, the mechanisms by which PIM1 contributes to oncogenesis have not been fully elucidated. Here, we performed a direct, unbiased chemical genetic screen to identify PIM1 substrates in prostate cancer cells. The PIM1 substrates we identified were involved in a variety of oncogenic processes, and included N-Myc Downstream-Regulated Gene 1 (NDRG1), which has reported roles in suppressing cancer cell invasion and metastasis. NDRG1 is phosphorylated by PIM1 at serine 330 (pS330), and the level of NDRG1 pS330 is associated higher grade prostate tumors. We have shown that PIM1 phosphorylation of NDRG1 at S330 reduced its stability, nuclear localization, and interaction with AR, resulting in enhanced cell migration and invasion.


Author(s):  
Amelia U. Schirmer ◽  
Lucy M. Driver ◽  
Megan T. Zhao ◽  
Carrow I. Wells ◽  
Julie E. Pickett ◽  
...  

Author(s):  
Adrian Rafael Murillo-de-Ozores ◽  
Alejandro Rodriguez-Gama ◽  
Hector Carbajal-Contreras ◽  
Gerardo Gamba ◽  
Maria Castaneda-Bueno

With No Lysine (K) kinase 4 (WNK4) belongs to a serine-threonine kinase family characterized by the atypical positioning of its catalytic lysine. Despite the fact that WNK4 has been found in many tissues, the majority of its study has revolved around its function in the kidney, specifically as a positive regulator of the thiazide-sensitive NaCl cotransporter (NCC) in the distal convoluted tubule (DCT) of the nephron. This is explained by the description of gain-of-function mutations in the gene encoding WNK4 that cause Familial Hyperkalemic Hypertension (FHHt). This disease is mainly driven by increased downstream activation of the Ste20-related Proline Alanine Rich Kinase (SPAK)/Oxidative Stress Responsive Kinase 1 (OSR1)-NCC pathway, which increases salt reabsorption in the DCT and indirectly impairs renal K+ secretion. Here, we review the large volume of information that has accumulated about different aspects of WNK4 function. We first review the knowledge on WNK4 structure and enumerate the functional domains and motifs that have been characterized. Then, we discuss WNK4 physiological functions based on the information obtained from in vitro studies and from a diverse set of genetically modified mouse models with altered WNK4 function. We then review in vitro and in vivo evidence on the different levels of regulation of WNK4. Finally, we go through the evidence that has suggested how different physiological conditions act through WNK4 to modulate NCC activity.


Theranostics ◽  
2016 ◽  
Vol 6 (1) ◽  
pp. 104-117 ◽  
Author(s):  
Kristell L.S. Chatalic ◽  
Mark Konijnenberg ◽  
Julie Nonnekens ◽  
Erik de Blois ◽  
Sander Hoeben ◽  
...  

2019 ◽  
Author(s):  
Zhen Wang ◽  
Junmei Kang ◽  
Shangang Jia ◽  
Tiejun Zhang ◽  
Zhihai Wu ◽  
...  

Abstract Background: Casein kinase 1 (CK1) family members are highly conserved serine/threonine kinase present in most eukaryotes with multiple biological functions. Arabidopsis MUT9-like kinases ( MLKs ) belong to a clade CK1 specific to the plant kingdom and have been implicated collectively in modulating flowering related processes. Three of the four MLKs ( MLK1/2/4 ) have been characterized, however, little is known about MLK3 , the most divergent MLKs. Results: We demonstrated that compared with wild type, mlk3 , a truncated MLK3 , flowered slightly early under long day conditions and ectopic expression of MLK3 rescued the morphological defects of mlk3 , indicating that MLK3 negatively regulates flowering. GA 3 application accelerated flowering of both wild type and mlk3 , suggesting that mlk3 had normal GA response. The recombinant MLK3-GFP was localized in the nucleus exclusively. In vitro kinase assay revealed that the nuclear protein MLK3 phosphorylated histone 3 at threonine 3 (H3T3ph). Mutation of a conserved catalytic residue (Lysine 175) abolished the kinase activity and resulted in failure to complement the early flowering phenotype of mlk3 . Interestingly, the global level of H3T3 phosphorylation in mlk3 did not differ significantly from wild type, suggesting the redundant roles of MLKs in flowering regulation. The transcriptomic analysis demonstrated that 425 genes significantly altered expression level in mlk3 relative to wild type. The mlk3 mlk4 double mutant generated by crossing mlk3 with mlk4 , a loss-of-function mutant of MLK4 showing late flowering, flowered between the two parental lines, suggesting that MLK3 played an antagonistic role to MLK4 in plant transition to flowering. Conclusions: A serine/threonine kinase encoding gene MLK3 is a casein kinase 1 specific to the plant species and represses flowering slightly. MLK3 located in nucleus catalyzes the phosphorylation of histone H3 at threonine 3 in vitro and an intact lysine residue (K175) is indispensible for the kinase activity. This study sheds new light on the delicate control of flowering by the plant-specific CK1 in Arabidopsis.


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