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Background: Arnicolide C, which is isolated from Centipeda minima, has excellent antitumor effects. However, the potential impacts and related mechanisms of action of arnicolide C in breast cancer remain unknown. Methods: The viability of breast cancer cells was measured using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and colony formation assays. For analysis of apoptosis and the cell cycle, flow cytometry was used. A molecular docking approach was used to explore the possible targets of arnicolide C. Western blot analysis was used to detect changes in the expression of 14-3-3θ and proteins in related pathways after arnicolide C treatment in breast cancer cells. The anti-breast cancer effect of arnicolide C in vivo was evaluated by establishing cell-derived xenograft (CDX) and patient-derived xenograft (PDX) models. Results: Arnicolide C inhibited proliferation, increased apoptosis, and induced G1 arrest. In particular, molecular docking analysis indicated that arnicolide C binds to 14-3-3θ. Arnicolide C reduced 14-3-3θ expression and inhibited its downstream signaling pathways linked to cell proliferation. Similar results were obtained in the CDX and PDX models. Conclusion: Arnicolide C can have an anti-breast cancer effect both in vitro and in vivo and can induce cell cycle arrest and increase apoptosis in vitro. The molecular mechanism may be related to the effect of arnicolide C on the expression level of 14-3-3θ. However, the specific mechanism through which arnicolide C affects 14-3-3θ protein expression still needs to be determined. [ABSTRACT FROM AUTHOR]

Abstract Background miR-203 was first indicated in maintaining skin homeostasis and innate immunity. Aberrant expression of miR-203 was found associated with pathological progressions of immune disorders, cancers, as well as neurodegenerations. Recently, increasing data on miR-203 in regulating neuroinflammation and neuronal apoptosis has raised extensive concern about the biological function of this microRNA. Methods Mouse model with ectopic miR-203 expression in the hippocampus was constructed by stereotactic injection of lentiviral expression vector of pre-miR-203. Association of miR-203 and mRNA of Akirin2, as well as the competition for miR-203 targeting between Akirin2 3ʹUTR and another recently characterized miR-203 target, 14-3-3θ, was verified using Dual-Luciferase Reporter Gene Assay and western blot. Microglia activation and pro-inflammatory cytokines expression in the hippocampus of mice overexpressing miR-203 was evaluated using immunohistochemistry analysis and western blot. Neuronal cell death was monitored using anti-caspase 8 in immunohistochemistry as well as TUNEL assay. Cognition of mice was assessed with a behavior test battery consisting of nesting behavior test, Barnes maze and fear conditioning test. Results Akirin2, an activator of NF‐κB signaling, was identified as a direct target of miR-203. By also targeting 14-3-3θ, a negative regulator of NF‐κB signaling, miR-203 displayed an overall pro-inflammatory role both in vitro and in vivo. Promoted nuclear translocation of NF‐κB and increased expression of proinflammatory cytokines were observed in cultured BV2 cells transfected with miR-203 mimics. Microglia activation and upregulation of NF‐κB, IL-1β and IL-6 were observed in mouse hippocampus with overexpression of miR-203. In addition, promoted neuronal cell death in the hippocampus and impaired neuronal activities resulted in cognitive dysfunction of mice with ectopic miR-203 expression in the hippocampus. Conclusion A pro-inflammatory and neurodisruptive role of miR-203 was addressed based on our data in this study. Given the identification of Akirin2 as a direct target of miR-203 and the competition with 14-3-3θ for miR-203 targeting, together with the findings of other signaling molecules in NF‐κB pathway as targets of miR-203, we proposed that miR-203 was a master modulator, fine-tunning neuroinflammation by juggling different components of NF‐κB signaling.

LRRK2 mutations are among the most common genetic causes for Parkinson's disease (PD), and toxicity is associated with increased kinase activity. 14-3-3 proteins are key interactors that regulate LRRK2 kinase activity. Phosphorylation of the 14-3-3θ isoform at S232 is dramatically increased in human PD brains. Here we investigate the impact of 14-3-3θ phosphorylation on its ability to regulate LRRK2 kinase activity. Both wildtype and the non-phosphorylatable S232A 14-3-3θ mutant reduced the kinase activity of wildtype and G2019S LRRK2, whereas the phosphomimetic S232D 14-3-3θ mutant had minimal effects on LRRK2 kinase activity, as determined by measuring autophosphorylation at S1292 and T1503 and Rab10 phosphorylation. However, wildtype and both 14-3-3θ mutants similarly reduced the kinase activity of the R1441G LRRK2 mutant. 14-3-3θ phosphorylation did not promote global dissociation with LRRK2, as determined by co-immunoprecipitation and proximal ligation assays. 14-3-3s interact with LRRK2 at several phosphorylated serine/threonine sites, including T2524 in the C-terminal helix, which can fold back to regulate the kinase domain. Interaction between 14-3-3θ and phosphorylated T2524 LRRK2 was important for 14-3-3θ's ability to regulate kinase activity, as wildtype and S232A 14-3-3θ failed to reduce the kinase activity of G2019S/T2524A LRRK2. Finally, we found that the S232D mutation failed to protect against G2019S LRRK2-induced neurite shortening in primary cultures, while the S232A mutation was protective. We conclude that 14-3-3θ phosphorylation destabilizes the interaction of 14-3-3θ with LRRK2 at T2524, which consequently promotes LRRK2 kinase activity and toxicity., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The chromosomal translocation t(4;11)(q21;q23), a hallmark of an aggressive form of acute lymphoblastic leukemia (ALL), encodes mixed‐lineage leukemia (MLL)‐AF4 oncogenic chimera that triggers aberrant transcription of genes involved in lymphocyte differentiation, including HOXA9 and MEIS1. The scaffold protein 14‐3‐3θ, which promotes the binding of MLL‐AF4 to the HOXA9 promoter, is a target of MiR‐27a, a tumor suppressor in different human leukemia cell types. We herein study the role of MiR‐27a in the pathogenesis of t(4;11) ALL. Reverse transcription quantitative PCR (qPCR) reveals that MiR‐27a and 14‐3‐3θ expression is inversely correlated in t(4;11) ALL cell lines; interestingly, MiR‐27a relative expression is significantly lower in patients affected by t(4;11) ALL than in patients affected by the less severe t(12;21) leukemia. In t(4;11) leukemia cells, ectopic expression of MiR‐27a decreases protein level of 14‐3‐3θ and of the key transcription factor RUNX1. We show for the first time that MiR‐27a also targets AF4 and MLL‐AF4; in agreement, MiR‐27a overexpression strongly reduces AF4 and MLL‐AF4 protein levels in RS4;11 cells. Consequent to AF4 and MLL‐AF4 downregulation, MiR‐27a overexpression negatively affects transcription of HOXA9 and MEIS1 in different t(4;11) leukemia cell lines. In agreement, we show through chromatin immunoprecipitation experiments that MiR‐27a overexpression impairs the binding of MLL‐AF4 to the HOXA9 promoter. Lastly, we found that MiR‐27a overexpression decreases viability, proliferation, and clonogenicity of t(4;11) cells, whereas it enhances their apoptotic rate. Overall, our study identifies the first microRNAthat strikes in one hit four crucial drivers of blast transformation in t(4;11) leukemia. Therefore, MiR‐27a emerges as a new promising therapeutic target for this aggressive and poorly curable form of leukemia. Significance statement: A growing body of evidence indicates that microRNAs targeting genes involved in modulating hematopoietic process are dysregulated t(4;11) acute leukemia, a very aggressive and refractory hematologic cancer. Here, we show that MiR‐27a is downregulated both in t(4;11) leukemia cell lines and primary patient samples. We demonstrate that MiR‐27a targets four crucial drivers of blast transformation, namely, 14‐3‐3θ, RUNX1, AF4, and mixed‐lineage leukemia (MLL)‐AF4 in t(4;11) leukemia cells. Thus, MiR‐27a, by striking these crucial oncogenes, functions as a tumor suppressor in t(4;11) leukemia and emerges as a new potential target for the therapy of this still poorly treatable form of leukemia. [ABSTRACT FROM AUTHOR]

Background: miR-203 was first indicated in maintaining skin homeostasis and innate immunity. Aberrant expression of miR-203 was found associated with pathological progressions of immune disorders, cancers, as well as neurodegenerations. Recently, increasing data on miR-203 in regulating neuroinflammation and neuronal apoptosis has raised extensive concern about the biological function of this microRNA. Methods: Mouse model with ectopic miR-203 expression in the hippocampus was constructed by stereotactic injection of lentiviral expression vector of pre-miR-203. Association of miR-203 and mRNA of Akirin2, as well as the competition for miR-203 targeting between Akirin2 3ʹUTR and another recently characterized miR-203 target, 14-3-3θ, was verified using Dual-Luciferase Reporter Gene Assay and western blot. Microglia activation and pro-inflammatory cytokines expression in the hippocampus of mice overexpressing miR-203 was evaluated using immunohistochemistry analysis and western blot. Neuronal cell death was monitored using anti-caspase 8 in immunohistochemistry as well as TUNEL assay. Cognition of mice was assessed with a behavior test battery consisting of nesting behavior test, Barnes maze and fear conditioning test. Results: Akirin2, an activator of NF‐κB signaling, was identified as a direct target of miR-203. By also targeting 14-3-3θ, a negative regulator of NF‐κB signaling, miR-203 displayed an overall pro-inflammatory role both in vitro and in vivo. Promoted nuclear translocation of NF‐κB and increased expression of proinflammatory cytokines were observed in cultured BV2 cells transfected with miR-203 mimics. Microglia activation and upregulation of NF‐κB, IL-1β and IL-6 were observed in mouse hippocampus with overexpression of miR-203. In addition, promoted neuronal cell death in the hippocampus and impaired neuronal activities resulted in cognitive dysfunction of mice with ectopic miR-203 expression in the hippocampus. Conclusion: A pro-inflammatory and neurodisruptive role of miR-203 was addressed based on our data in this study. Given the identification of Akirin2 as a direct target of miR-203 and the competition with 14-3-3θ for miR-203 targeting, together with the findings of other signaling molecules in NF‐κB pathway as targets of miR-203, we proposed that miR-203 was a master modulator, fine-tunning neuroinflammation by juggling different components of NF‐κB signaling. [ABSTRACT FROM AUTHOR]

MiR-203 was identified as a hub of a potential regulatory miRNA network in central nervous system. Overexpressing of miR-203 in the frontal cortex of C57BL/6J wild type mouse induced neurodegeneration by increasing the apoptotic pathway and neuron death. AFF4, a transcription factor, was identified as a new bona fida protein target of miR-203 in CNS. The miRNA:mRNA interaction of miR-203 and AFF4 was verified using Dural-luciferase assay. Down-regulated expression of AFF4 was induced by overexpressing miR-203 both in vitro and in vivo. Open field test, Y maze and Morris water maze test were conducted for the behavioral assessment of the mice with stereotactic injection of lentiviral vector overexpressing miR-203 in the hippocampus. No anxiety-like behavior or impaired cognition was noticed in these mice. Consistent with the results of the behavioral assessment, the electron micrograph and Nissl staining revealed no significant change in the synaptic density and no neuron injuries in the hippocampus of mice overexpressing miR-203, respectively. Our results indicated that instead of promoting neurodegenerative phenotype, a more profound function should be ascribed to miR-203 in regulating neuron behavioral activities and cognition. Neuron-type specific functions of miR-203 are likely to be executed via its various downstream protein interactors. • We reported that AFF4, a transcription factor, was identified as a new bona fida protein target of miR-203 in CNS. • The miRNA:mRNA interaction of miR-203 and AFF4 was verified using Dural-luciferase assay. • Down-regulated expression of AFF4 was induced by overexpressing miR-203 both in vitro and in vivo. • Open field test, Y maze and Morris water maze test were conducted for the behavioral assessments of the mice with stereotactic injection of lentiviral vector overexpressing miR-203 in the hippocampus. • The electron micrograph and Nissl staining revealed no significant change in the synaptic density and no neuron injuries in the mice overexpressing miR-203 in the hippocampus. [ABSTRACT FROM AUTHOR]

The rhizome of Chinese medical plant QingTeng (scientific name: Sinomenium acutum (Thunb.) Rehd. et Wils.) is widely used by traditional medical doctors for anti-inflammation and immunoregulatory in China and other Asian countries. The purpose of this study was to evaluate the effects and possible mechanisms of sinomenine resistance against DSS-induced inflammation in vitro and in vivo. The UC model was induced by treating female mice with 3% DSS in vivo and human colonic epithelial cells (Hcoepic) with 0.8 mg/ml DSS in vitro. The mice and Hcoepic were then treated with sinomenine. Inflammatory factors were detected using ELISA and qRT-PCR. Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p65 and 14-3-3θ were analyzed by bioinformatic analysis and verified by western blotting, immunofluorescent staining or immunohistochemistry. DSS-induced Hcoepic underwent high inflammation and oxidative stress conditions, whereas sinomenine reduced the uncontrolled immune microenvironment by suppressing NF-κB signaling and targeting 14-3-3θ. Knockdown of 14-3-3θ decreased the protective effect of sinomenine against DSS-induced inflammation in vitro. Moreover, sinomenine promoted 14-3-3θ protein expression and inhibited NF-κB p65 signaling in DSS-induced mice. These findings suggest that 14-3-3θ plays an important role in sinomenine against DSS treatment, and sinomenine could be considered a potential drug for the treatment of UC. • SIN alleviates colon injury in DSS-induced UC in mice. • SIN down-regulates the inflammation resist DSS via inhibiting NF-κB signal. • 14-3-3θ plays a protect role in SIN administration. [ABSTRACT FROM AUTHOR]

Objective: To investigate the expression and clinical significance of 14-3-3 θ protein in human nasopharyngeal carcinoma. Methods: Expression status of 14-3-30 was detected by immunohistochemistry in 72 cases of human nasopharyngeal carcinoma and normal nasopharyngeal tissues. Expressions and correlations of 14-3-3 θ were analyzed. Results: In 72 cases of nasopharyngeal carcinoma and normal nasopharyngeal tissues, the positive expressions of 14-3-3 θ were 69.4 % and 15.2 %. The chi square test suggested that 14-3-3 θ expression was correlated with clinical stages (P=0.045). lymph node metastasis (P<0.001). recurrences (P=0.041). while it was not correlated with age (P=0.444). sex (P=0.795). histologic subtype (P=0.468). Correlation analysis suggested that 14-3-3θ expressions were positively correlated with clinical stages (r= -0.256. P=0.030). lymph node metastasis (r=0.506, P<0.001). recurrences (r=0.106. P=0.033). while it was negatively correlated with age. sex, and histologic subtype (P>0.05). Conclusion: In human nasopharyngeal carcinoma, expressions of 14-3-3θ were increased and correlated with clinical stages and metastasis. [ABSTRACT FROM AUTHOR]

Objective: In order to further study the effect of biology behavior of the gene 14-3-3θ to breast cancer, to build a recombinant vector and breast cancer cell line which can over express gene 14-3-3θ. Methods: The gene 14-3-3θ in the pENTR 3C DUAL is synthesized by a company, we put the gene 14-3-3θ into the vector pcDNA4.0 which can product 14-3-3θ in eukaryotic cells by recombinant DNA technology and then transfect the 293T, we identify the overexpression of the recombinant vector by the western blot and PCR. At last, we transfect the breast cancer cell by the recombinant vector and screen the breast cancer cell with Zeocin. Results: Successfully construct the recombinant vector and breast cancer cell line which can over express 14-3-3θ. Which shows that gene 14-3-3θ may play an important role in the early diagnosis and prognosis of breast cancer prediction. [ABSTRACT FROM AUTHOR]

Abstract: The p62 protein has been identified as a major component of the protein aggregations associated with neurodegenerative disease. Oxidative insult has also been identified as a principal cause of neurodegenerative disease. Thus, in the present study, we investigated the potential role of p62 in oxidative stress-induced cell death in SH-SY5Y human neuroblastoma cells. The results indicated that H2O2 treatment induced p62 expression in SH-SY5Y cells. In addition, p62 showed neuroprotective effects against H2O2-induced cell death in differentiated SH-SY5Y cells. p62 expression prolonged Akt phosphorylation during the later stages of H2O2-induced cell death. Furthermore, coexpression of p62 and wild-type PDK1, the upstream kinase of Akt, further increased Akt phosphorylation and cell viability, whereas the expression of kinase-defective PDK1 reversed the cytoprotective effects of p62 under oxidative stress. Overexpression of p62 led to the dissociation of PDK1 from the 14-3-3θ protein, which is thought to be a negative regulator of PDK1 kinase activity. These findings suggest a mechanism that involves the p62-mediated modulation of the interaction between signaling molecules and results in cell survival. [Copyright &y& Elsevier]

Background: Glioma is the most common and aggressive primary brain tumor with polygenic susceptibility. The cytoplasmic/nuclear shuttling protein, SLC2A4RG (SLC2A4 regulator), has been identified in the 20q13.33 region influencing glioma susceptibility by genome-wide association studies (GWAS) and fine mapping analyses., Methods: To discover the expression of SLC2A4RG and its relationship with patient prognosis, tissue microarray containing glioma samples and normal brains was constructed followed by immunohistochemical staining. The role of SLC2A4RG on cell proliferation, cell cycle, and apoptosis was evaluated by gain- and loss-of-function assays in vivo, and subcutaneous and intracranial xenografts were performed to assess its functional effects. The mechanism underlying SLC2A4RG was further investigated via luciferase reporter analyses, ChIP, mass spectrometry, Co-IP, immunofluorescence, etc. FINDINGS: The potential tumor suppressor role of SLC2A4RG was further validated by in vitro and in vivo experiments that SLC2A4RG could attenuate cell proliferation via G2/M phase arrest and induce glioma cell apoptosis by direct transactivation of caspase-3 and caspase-6. Moreover, its function displaying showed to depend on the nuclear transportation of SLC2A4RG, however, bound with 14-3-3θ, it would be sequestered in the cytoplasm followed by reversal effect., Interpretation: We identify a new pro-oncogenic mechanism whereby 14-3-3θ negatively regulates the nuclear function of the tumor suppressor SLC2A4RG, with significant therapeutic implications for the intervention of human glioma. FUND: This work was supported by the National Natural Science Foundation of China (81372706, 81572501, and 81372235)., (Copyright © 2019. Published by Elsevier B.V.)

Our previous study reported that retinoic acid induced 16 (RAI16) could enhance tumorigenesis in hepatocellular carcinoma (HCC). However, the cellular functions of RAI16 are still unclear. In this study, by immunoprecipitation and tandem (MS/MS) mass spectrometry analysis, we identified that RAI16 interacted with the type II regulatory subunit of PKA (PKA-RIIα), acting as a novel protein kinase A anchoring protein (AKAP). In addition, RAI16 also interacted with heat shock protein 70 (HSP70) and 14-3-3θ. Further studies indicated that RAI16 mediated PKA phosphorylation of HSP70 at serine 486, resulting in anti-apoptosis events. RAI16 was also phosphorylated by the anchored PKA at serine 325, which promoted the recruitment of 14-3-3θ, which, in turn, inhibited RAI16 mediated PKA phosphorylation of HSP70. These findings offer mechanism insight into RAI16 mediated anti-apoptosis signaling in HCC.