DNA methylation of the MAP3K10 gene may participate in the development of intracranial aneurysm.

BACKGROUND: The goal of this study was to explore the association between mitogen-activated protein kinase kinase kinase 10 (MAP3K10) methylation and blood lipid levels and intracranial aneurysm (IA) risk. MATERIALS AND METHODS: A total of 96 age- and sex-matched investigators participated in the assessment of MAP3K10 methylation. Fourteen CpG sites of the MAP3K10 gene were selected for methylated-pyrosequencing. Human brain vascular smooth muscle cell was used to assess the regulatory role of DNA methylation in MAP3K10 gene transcription. RESULTS: MAP3K10 mean methylation was positively correlated with triglyceride (TG, r = 0.388; p = 0.007) in men, but negatively correlated with TG (r = -0.434; p = 0.002) in women. MAP3K10 methylation in patients with IA was significantly lower than that in controls (p < 0.05), and this phenomenon was more significant in women (12 CpG sites presented significance at p < 0.05). MAP3K10 methylation might be a potential predictor of the risk of IA (CpG1, AUC = 0.81, p < 0.001; mean methylation, AUC = 0.69, p = 0.001). The predictive value was also more significant in women (CpG1: AUC = 0.86, p < 0.001; mean methylation: AUC = 0.73, p = 0.006). No significant association was found between DNA methylation and MAP3K10 gene transcription in vitro experiment. CONCLUSION: Patients with IA had lower MAP3K10 methylation levels than healthy controls. MAP3K10 methylation may be a potential predictor of IA risk, particularly in women.

MiR-146b-3p regulates proliferation of pancreatic cancer cells with stem cell-like properties by targeting MAP3K10.

Purpose: Cancer stem cells (CSCs) initiate and maintain tumorigenesis due to their unique pluripotency. However, pancreatic stem cell gene signatures are not completely revealed yet. Here, we isolated pancreatic cancer stem cells (P-CSCs) and exploited their distinct genome-wide mRNA and miRNA expression profiles using microarrays. Methods: CD24+ CD44+ ESA+ cells were isolated from two pancreatic xenograft cells by the flow cytometry and identified the stem cell-like properties by the tumor formation, self-renew and chemoresistance. Microarrays and qRT-PCR were used to exploit their distinct Genome-wide mRNA and miRNA expression profiles. The function and candidate target genes of key microRNA were detected after Ectopic restoration in the pancreatic cancer cell lines MIA Paca-2 (CSChigh) and BxPC-3 (CSClow). Results: In this study, we isolated P-CSCs from two xenografts cells. Genome-wide profiling experiments showed 479 genes and 15 microRNAs specifically expressed in the P-CSCs, including genes involved in TGF-ß and p53 signaling pathways and particularly miR-146b-3p as the most significantly downregulated miRNA. We confirmed miR-146b-3p as a downregulated signature in pancreatic cancer tissues and cell line MIA Paca-2 (CSChigh) cells. Ectopic restoration of miR-146b-3p expression with pre-miR reduced cell proliferation, induced apoptosis, increased G1 phase and reduced S phase in cell cycle in MIA Paca-2 (CSChigh), but not in BxPC-3 (CSClow). Re-expression of miR-146b-3p with lentivirus significantly inhibited tumorigenicity in vivo in MIA Paca-2, but slightly in BxPC-3. Furthermore, we demonstrated that miR-146b-3p directly targeted MAP3K10 and might activate Hedgehog pathway as well through DYRK2 and GLI2. Conclusions: These results suggest that P-CSCs have distinct gene expression profiles. MiR-146b-3p inhibits proliferation and induced apoptosis in P-CSCs high cells lines by targeting MAP3K10. Targeting P-CSCs specific genes may provide novel strategies for therapeutic purposes.

DNA methylation­regulated miR­155­5p depresses sensitivity of esophageal carcinoma cells to radiation and multiple chemotherapeutic drugs via suppression of MAP3K10.

Radiotherapy and chemotherapy are two major treatment options for esophageal carcinoma, and heterogeneous treatment effects are observed in the clinical setting to provide an overall 5­year survival rate of ~20%. Hence, defining the molecular mechanisms that affect the chemoradiotherapy response is vital to achieve an optimal outcome. The present study revealed that miR­155­5p may be involved in esophageal squamous cell carcinoma (ESCC). By means of reverse transcription­PCR, the present study defined its differential expression pattern in six ESCC cell lines that were associated with resistance to radiation. Ectopic expression of miR­155­5p promoted DNA damage repair and induced resistance against radiation by non­homologous end joining repair. It also enhanced chemoresistance, proliferation, and migration and invasion of ESCC cells. By further screening its potential target genes, the present study identified MAP3K10 as the direct target gene to exert its anti­chemoradiation functions. The results also demonstrated that its differential expression pattern was negatively regulated by the methylation status of the upstream CpG island. Overall, the results of the present study demonstrated that miR­155­5p is a key molecule for understanding the heterogeneous responses of ESCC to chemoradiotherapy, and may be used in personalized treatment plans for this high mortality tumor in the future.

Methionine stimulates GlyRS phosphorylation via the GPR87-CDC42/Rac1-MAP3K10 signaling pathway.

Glycyl-tRNA synthetase (GlyRS) has non-canonical roles beyond aminoacylation, but the molecular mechanism is largely unknown. We have previously found that GlyRS is phosphorylated in the cytoplasm of bovine mammary epithelial cells (bMECs) in response to amino acid stimulation, and the phosphorylated GlyRS enters nucleus to stimulate gene expression for milk synthesis. In this study, we aim to uncover the upstream kinase of GlyRS and reveal the signaling pathways that methionine (Met) stimulates GlyRS phosphorylation. We show that mitogen-activated protein kinase 10 (MAP3K10) interacts with GlyRS in bMECs by Co-IP, mass spectrometry, and Western blotting analysis. We further identify that MAP3K10 is an upstream kinase of GlyRS by in vitro kinase assay and MAP3K10 stimulates NFκB1 phosphorylation via activating GlyRS. We also uncover that Met stimulates GlyRS phosphorylation via the GPR87-CDC42/Rac1-MAP3K10 signaling pathway. Our findings help to understand the molecular mechanism of GlyRS in cellular signaling transduction.

Neurocalcin Delta Knockout Impairs Adult Neurogenesis Whereas Half Reduction Is Not Pathological.

Neurocalcin delta (NCALD) is a brain-enriched neuronal calcium sensor and its reduction acts protective against spinal muscular atrophy (SMA). However, the physiological function of NCALD and implications of NCALD reduction are still elusive. Here, we analyzed the ubiquitous Ncald knockout in homozygous (Ncald KO/KO) and heterozygous (Ncald KO/WT) mice to unravel the physiological role of NCALD in the brain and to study whether 50% NCALD reduction is a safe option for SMA therapy. We found that Ncald KO/KO but not Ncald KO/WT mice exhibit significant changes in the hippocampal morphology, likely due to impaired generation and migration of newborn neurons in the dentate gyrus (DG). To understand the mechanism behind, we studied the NCALD interactome and identified mitogen-activated protein kinase kinase kinase 10 (MAP3K10) as a novel NCALD interacting partner. MAP3K10 is an upstream activating kinase of c-Jun N-terminal kinase (JNK), which regulates adult neurogenesis. Strikingly, the JNK activation was significantly upregulated in the Ncald KO/KO brains. Contrary, neither adult neurogenesis nor JNK activation were altered by heterozygous Ncald deletion. Taken together, our study identifies a novel link between NCALD and adult neurogenesis in the hippocampus, possibly via a MAP3K10-JNK pathway and emphasizes the safety of using NCALD reduction as a therapeutic option for SMA.

The TGFß-induced phosphorylation and activation of p38 mitogen-activated protein kinase is mediated by MAP3K4 and MAP3K10 but not TAK1.

The signalling pathways downstream of the transforming growth factor beta (TGFß) family of cytokines play critical roles in all aspects of cellular homeostasis. The phosphorylation and activation of p38 mitogen-activated protein kinase (MAPK) has been implicated in TGFß-induced epithelial-to-mesenchymal transition and apoptosis. The precise molecular mechanisms by which TGFß cytokines induce the phosphorylation and activation of p38 MAPK are unclear. In this study, I demonstrate that TGFß-activated kinase 1 (TAK1/MAP3K7) does not play a role in the TGFß-induced phosphorylation and activation of p38 MAPK in MEFs and HaCaT keratinocytes. Instead, RNAi-mediated depletion of MAP3K4 and MAP3K10 results in the inhibition of the TGFß-induced p38 MAPK phosphorylation. Furthermore, the depletion of MAP3K10 from cells homozygously knocked-in with a catalytically inactive mutant of MAP3K4 completely abolishes the TGFß-induced phosphorylation of p38 MAPK, implying that among MAP3Ks, MAP3K4 and MAP3K10 are sufficient for mediating the TGFß-induced activation of p38 MAPK.