ABSTRACT
CDC-like kinase 3 (CLK3) is a dual specificity kinase that functions on substrates containing serine/threonine and tyrosine. But its role in human cancer remains unknown. Herein, we demonstrated that CLK3 was significantly up-regulated in cholangiocarcinoma (CCA) and identified a recurrent Q607R somatic substitution that represented a gain-of-function mutation in the CLK3 kinase domain. Gene ontology term enrichment suggested that high CLK3 expression in CCA patients mainly was associated with nucleotide metabolism reprogramming, which was further confirmed by comparing metabolic profiling of CCA cells. CLK3 directly phosphorylated USP13 at Y708, which promoted its binding to c-Myc, thereby preventing Fbxl14-mediated c-Myc ubiquitination and activating the transcription of purine metabolic genes. Notably, the CCA-associated CLK3-Q607R mutant induced USP13-Y708 phosphorylation and enhanced the activity of c-Myc. In turn, c-Myc transcriptionally up-regulated CLK3. Finally, we identified tacrine hydrochloride as a potential drug to inhibit aberrant CLK3-induced CCA. These findings demonstrate that CLK3 plays a crucial role in CCA purine metabolism, suggesting a potential therapeutic utility.
Subject(s)
Bile Duct Neoplasms/drug therapy , Cellular Reprogramming/drug effects , Cholangiocarcinoma/drug therapy , Drug Delivery Systems , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein-Tyrosine Kinases/antagonists & inhibitors , Purines/metabolism , Tacrine/pharmacology , Amino Acid Substitution , Bile Duct Neoplasms/enzymology , Bile Duct Neoplasms/genetics , Cell Line, Tumor , Cholangiocarcinoma/enzymology , Cholangiocarcinoma/genetics , Gain of Function Mutation , Gene Expression Regulation, Enzymologic/drug effects , Gene Expression Regulation, Neoplastic/drug effects , HEK293 Cells , Humans , Mutation, Missense , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/genetics , Phosphorylation , Protein Serine-Threonine Kinases/biosynthesis , Protein Serine-Threonine Kinases/genetics , Protein-Tyrosine Kinases/biosynthesis , Protein-Tyrosine Kinases/genetics , Up-Regulation/drug effectsABSTRACT
LncRNAs have been proven closely correlated to tumor progression. A recent study identified LncRNA TPT1-AS1 (TPT1-AS1) as one of the liver-metastasis associated LncRNAs in colorectal cancer (CRC). In this study, we report that TPT1-AS1 is upregulated in CRC tissues, which is associated with poor prognosis. Functional assays unravel a pro-angiogenesis and metastasis role of TPT1-AS1. Mechanistically, Flexmap 3D assays reveal that TPT1-AS1 upregulates the VEGFA secretion in CRC cells. RNA immunoprecipitation and mRNA stability assays further show that TPT1-AS1 interacts with nuclear factor 90 (NF90) and subsequently promotes the association between NF90 and VEGFA mRNA, which leads to the upregulation of VEGFA mRNA stability. Therefore, we elucidate a new regulatory mechanism of TPT1-AS1 in CRC angiogenesis and targeting the TPT1-AS1/NF90/VEGFA axis may provide a useful strategy for diagnosis and treatment for colorectal cancer patients.
Subject(s)
Biomarkers, Tumor , Colorectal Neoplasms , Neoplasm Metastasis , Neovascularization, Pathologic , RNA, Antisense , RNA, Long Noncoding , Vascular Endothelial Growth Factor A , Humans , Biomarkers, Tumor/metabolism , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Gene Expression Regulation, Neoplastic , Neoplasm Metastasis/genetics , Neovascularization, Pathologic/genetics , Nuclear Factor 90 Proteins/metabolism , RNA, Long Noncoding/metabolism , Signal Transduction , Tumor Protein, Translationally-Controlled 1 , Up-Regulation , Vascular Endothelial Growth Factor A/metabolismABSTRACT
Abducens nerve palsy (ANP) is commonly seen in patients with diabetes mellitus. The validity of acupuncture as a traditional Chinese medicine method in peripheral nerve repair is well established. However, its efficacy in randomized controlled trials remains unclear. Herein, we designed a protocol for a prospective, single-center, randomized controlled trial to investigate the effect of intraorbital electroacupuncture on diabetic ANP. We plan to recruit 60 patients with diabetic ANP, and randomly divide them into treatment and control groups. Patients in both groups will continue their glucose-lowering therapy. A neural nutrition drug will be given to both groups for six weeks. The treatment group will also receive intraorbital electroacupuncture therapy. We will assess efficacy of treatment, eyeball movement, diplopia deviation and the levels of fasting blood-glucose and glycosylated hemoglobin before treatment at 2, 4, and 6 weeks after treatment. The efficacy and recurrence will be investigated during follow-up (1 month after intervention). This protocol was registered at Chinese Clinical Trial Registry on 16 January 2015 (ChiCTR-IPR-15005836). This study was approved by the Ethics Committee of First Affiliated Hospital of Harbin Medical University of China (approval number: 201452). All protocols will be in accordance with Declaration of Helsinki, formulated by the World Medical Association. Written informed consent will be provided by participants. We envisage that the results of this clinical trial will provide evidence for promoting clinical use of this new therapy for management of ANP.