A non-canonical role of the inner kinetochore in regulating sister-chromatid cohesion at centromeres.

The 16-subunit Constitutive Centromere-associated Network (CCAN)-based inner kinetochore is well-known for connecting centromeric chromatin to the spindle-binding outer kinetochore. Here, we report a non-canonical role for the inner kinetochore in directly regulating sister-chromatid cohesion at centromeres. We provide biochemical, X-ray crystal structure, and intracellular ectopic localization evidence that the inner kinetochore directly binds cohesin, a ring-shaped multi-subunit complex that holds sister chromatids together from S-phase until anaphase onset. This interaction is mediated by binding of the 5-subunit CENP-OPQUR sub-complex of CCAN to the Scc1-SA2 sub-complex of cohesin. Mutation in the CENP-U subunit of the CENP-OPQUR complex that abolishes its binding to the composite interface between Scc1 and SA2 weakens centromeric cohesion, leading to premature separation of sister chromatids during delayed metaphase. We further show that CENP-U competes with the cohesin release factor Wapl for binding the interface of Scc1-SA2, and that the cohesion-protecting role for CENP-U can be bypassed by depleting Wapl. Taken together, this study reveals an inner kinetochore-bound pool of cohesin, which strengthens centromeric sister-chromatid cohesion to resist metaphase spindle pulling forces.

Olfactory sensory experience regulates gliomagenesis via neuronal IGF1.

Animals constantly receive various sensory stimuli, such as odours, sounds, light and touch, from the surrounding environment. These sensory inputs are essential for animals to search for food and avoid predators, but they also affect their physiological status, and may cause diseases such as cancer. Malignant gliomas-the most lethal form of brain tumour1-are known to intimately communicate with neurons at the cellular level2,3. However, it remains unclear whether external sensory stimuli can directly affect the development of malignant glioma under normal living conditions. Here we show that olfaction can directly regulate gliomagenesis. In an autochthonous mouse model that recapitulates adult gliomagenesis4-6 originating in oligodendrocyte precursor cells (OPCs), gliomas preferentially emerge in the olfactory bulb-the first relay of brain olfactory circuitry. Manipulating the activity of olfactory receptor neurons (ORNs) affects the development of glioma. Mechanistically, olfaction excites mitral and tufted (M/T) cells, which receive sensory information from ORNs and release insulin-like growth factor 1 (IGF1) in an activity-dependent manner. Specific knockout of Igf1 in M/T cells suppresses gliomagenesis. In addition, knocking out the IGF1 receptor in pre-cancerous mutant OPCs abolishes the ORN-activity-dependent mitogenic effects. Our findings establish a link between sensory experience and gliomagenesis through their corresponding sensory neuronal circuits.

A prefrontal-habenular circuitry regulates social fear behaviour.

The medial prefrontal cortex (mPFC) has been implicated in the pathophysiology of social impairments including social fear. However, the precise subcortical partners that mediate mPFC dysfunction on social fear behaviour have not been identified. Employing a social fear conditioning paradigm, we induced robust social fear in mice and found that the lateral habenula (LHb) neurons and LHb-projecting mPFC neurons are synchronously activated during social fear expression. Moreover, optogenetic inhibition of the mPFC-LHb projection significantly reduced social fear responses. Importantly, consistent with animal studies, we observed an elevated prefrontal-habenular functional connectivity in subclinical individuals with higher social anxiety characterized by heightened social fear. These results unravel a crucial role of the prefrontal-habenular circuitry in social fear regulation and suggest that this pathway could serve as a potential target for the treatment of social fear symptom often observed in many psychiatric disorders.

HTLV-1 activates YAP via NF-κB/p65 to promote oncogenesis.

Adult T-cell leukemia/lymphoma (ATL) is an aggressive malignancy caused by human T-cell leukemia virus type 1 (HTLV-1) infection. HTLV-1 exerts its oncogenic functions by interacting with signaling pathways involved in cell proliferation and transformation. Dysregulation of the Hippo/YAP pathway is associated with multiple cancers, including virus-induced malignancies. In the present study, we observe that expression of YAP, which is the key effector of Hippo signaling, is elevated in ATL cells by the action of the HTLV-1 Tax protein. YAP transcriptional activity is remarkably enhanced in HTLV-1-infected cells and ATL patients. In addition, Tax activates the YAP protein via a mechanism involving the NF-κB/p65 pathway. As a mechanism for this cross talk between the Hippo and NF-κB pathways, we found that p65 abrogates the interaction between YAP and LATS1, leading to suppression of YAP phosphorylation, inhibition of ubiquitination-dependent degradation of YAP, and YAP nuclear accumulation. Finally, knockdown of YAP suppresses the proliferation of ATL cells in vitro and tumor formation in ATL-engrafted mice. Taken together, our results suggest that p65-induced YAP activation is essential for ATL pathogenesis and implicate YAP as a potential therapeutic target for ATL treatment.

Smurf1 polyubiquitinates on K285/K282 of the kinases Mst1/2 to attenuate their tumor-suppressor functions.

Sterile 20-like kinases Mst1 and Mst2 (Mst1/2) and large tumor suppressor 1/2 are core kinases to mediate Hippo signaling in maintaining tissue homeostasis. We have previously demonstrated that Smad ubiquitin (Ub) regulatory factor 1 (Smurf1), a HECT-type E3 ligase, ubiquitinates and in turn destabilizes large tumor suppressor 1/2 to induce the transcriptional output of Hippo signaling. Here, we unexpectedly find that Smurf1 interacts with and polyubiquitinates Mst1/2 by virtue of K27- and K29-linked Ub chains, resulting in the proteasomal degradation of Mst1/2 and attenuation of their tumor-suppressor functions. Among the potential Ub acceptor sites on Mst1/2, K285/K282 are conserved and essential for Smurf1-induced polyubiquitination and degradation of Mst1/2 as well as transcriptional output of Hippo signaling. As a result, K285R/K282R mutation of Mst1/2 not only negates the transcriptional output of Hippo signaling but enhances the tumor-suppressor functions of Mst1/2. Together, we demonstrate that Smurf1-mediated polyubiquitination on K285/K282 of Mst1/2 destabilizes Mst1/2 to attenuate their tumor-suppressor functions. Thus, the present study identifies Smurf1-mediated ubiquitination of Mst1/2 as a hitherto uncharacterized mechanism fine-tuning the Hippo signaling pathway and may provide additional targets for therapeutic intervention of diseases associated with this important pathway.

Direct Synthesis of α-Ketothioamide Derivatives through a One-Pot Reaction of Sulfur Ylides, Nitrosobenzenes, and Thioacetic Acid.

A one-pot approach has been developed for the synthesis of α-ketothioamide derivatives from sulfur ylides, nitrosobenzenes, and thioacetic acid. This protocol is carried out under mild reaction conditions in generally moderate to excellent yields without any precious catalysts, affording the derivatives with structural diversity. Additionally, a possible mechanism for this chemical transformation is proposed.

APP mediates tau uptake and its overexpression leads to the exacerbated tau pathology.

Alzheimer's disease (AD), as the most common type of dementia, has two pathological hallmarks, extracellular senile plaques composed of ß-amyloid peptides and intracellular neurofibrillary tangles containing phosphorylated-tau protein. Amyloid precursor protein (APP) and tau each play central roles in AD, although how APP and tau interact and synergize in the disease process is largely unknown. Here, we showed that soluble tau interacts with the N-terminal of APP in vitro in cell-free and cell culture systems, which can be further confirmed in vivo in the brain of 3XTg-AD mouse. In addition, APP is involved in the cellular uptake of tau through endocytosis. APP knockdown or N-terminal APP-specific antagonist 6KApoEp can prevent tau uptake in vitro, resulting in an extracellular tau accumulation in cultured neuronal cells. Interestingly, in APP/PS1 transgenic mouse brain, the overexpression of APP exacerbated tau propagation. Moreover, in the human tau transgenic mouse brain, overexpression of APP promotes tau phosphorylation, which is significantly remediated by 6KapoEp. All these results demonstrate the important role of APP in the tauopathy of AD. Targeting the pathological interaction of N-terminal APP with tau may provide an important therapeutic strategy for AD.

Cephaeline promotes ferroptosis by targeting NRF2 to exert anti-lung cancer efficacy.

CONTEXT: Cephaeline is a natural product isolated from ipecac (Cephaelis ipecacuanha [Brot.] A. Rich. [Rubiaceae]). It exhibits promising anti-lung cancer activity and ferroptosis induction may be a key mechanism for its anti-lung cancer effect. OBJECTIVES: This study investigates the anti-lung cancer activity and mechanisms of cephaeline both in vitro and in vivo. MATERIALS AND METHODS: H460 and A549 lung cancer cells were used. The cephaeline inhibition rate on lung cancer cells was detected via a Cell Counting Kit-8 assay after treatment with cephaeline for 24 h. Subsequently, the concentrations of 25, 50 and 100 nM were used for in vitro experiments. In addition, the antitumour effects of cephaeline (5, 10 mg/kg) in vivo were evaluated after 12 d of cephaeline treatment. RESULTS: Cephaeline showed significant inhibitory effects on lung cancer cells, and the IC50 of cephaeline on H460 and A549 at 24, 48 and 72 h were 88, 58 and 35 nM, respectively, for H460 cells and 89, 65 and 43 nM, respectively, for A549 cells. Meanwhile, we demonstrated that ferroptosis is the key mechanism of cephaeline against lung cancer. Finally, we found that cephaeline induced ferroptosis in lung cancer cells by targeting NRF2. DISCUSSION AND CONCLUSION: We demonstrated for the first time that cephaeline inhibits NRF2, leading to ferroptosis in lung cancer cells. These findings may contribute to the development of innovative therapeutics for lung cancer.

Trpm2 deficiency in microglia attenuates neuroinflammation during epileptogenesis by upregulating autophagy via the AMPK/mTOR pathway.

Epilepsy is one of the most common neurological disorders. Neuroinflammation involving the activation of microglia and astrocytes constitutes an important and common mechanism in epileptogenesis. Transient receptor potential melastatin 2 (TRPM2) is a calcium-permeable, non-selective cation channel that plays pathological roles in various inflammation-related diseases. Our previous study demonstrated that Trpm2 knockout exhibits therapeutic effects on pilocarpine-induced glial activation and neuroinflammation. However, whether TRPM2 in microglia and astrocytes plays a common pathogenic role in this process and the underlying molecular mechanisms remained undetermined. Here, we demonstrate a previously unknown role for microglial TRPM2 in epileptogenesis. Trpm2 knockout in microglia attenuated kainic acid (KA)-induced glial activation, inflammatory cytokines production and hippocampal paroxysmal discharges, whereas Trpm2 knockout in astrocytes exhibited no significant effects. Furthermore, we discovered that these therapeutic effects were mediated by upregulated autophagy via the adenosine monophosphate activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway in microglia. Thus, our findings highlight an important deleterious role of microglial TRPM2 in temporal lobe epilepsy.

Direct Access to 3-Thioether-Substituted Dihydrofuro[2,3-b]benzofurans via Tandem Reactions of Sulfur Ylides and 2-Nitrobenzofurans.

The synthesis of 3-thioether-substituted dihydrofuro[2,3-b]benzofurans involving the [3 + 2] coupling of sulfur ylides with 2-nitrobenzofurans has been realized in moderate to good yields under mild conditions without any precious catalysts or additives. It is worth mentioning that the reutilization of the departed nitro-anion in the reaction process facilitates this new chemical transformation and presents a manner of high atom economy to provide products with a complex structure.

Discovery of novel hypoxia-activated, nitroimidazole constructed multi-target kinase inhibitors on the basis of AZD9291 for the treatment of human lung cancer.

A group of 4-(1-methyl-1H-indol-3-yl)pyrimidin-2-amine derivatives containing a hypoxia-activated nitroimidazole group were designed as EGFR inhibitors. Among this series, A14 was identified as the optimal compound, exhibiting potent anti-proliferative activities against H1975 and HCC827 cells. Under hypoxic condition, the anti-proliferative activities of A14 improved by 4-6-fold (IC50 < 10 nM), indicating its hypoxia-selectivity. A14's high potency may be attributed to its inhibition against multiple kinases, including EGFR, JAK2, ROS1, FLT3, FLT4 and PDGFRα, which was confirmed by binding assays on a panel of 30 kinases. Furthermore, A14 exhibited good bio-reductive property and could bind with nucleophilic amino acids after being activated under hypoxic conditions. With its anti-proliferative activities and selectivity for hypoxia and oncogenic kinases, A14 shows promise as a multi-target kinase inhibitor for cancer therapy.

Exploration of novel dihydroquinoxalinone derivatives as EGFRL858R/T790M tyrosine kinase inhibitors for the treatment of non-small-cell lung cancer.

To overcome or delay the drug-resistance of first-generation epidermal growth factor receptor (EGFR) kinase inhibitors and non-selectivity toxicity mediated by second-generation inhibitors, splicing principle was employed to design and synthesize a series of Osimertinib derivatives containing dihydroquinoxalinone (8-30) as the novel third-generation inhibitors against double mutant L858R/T790M in EGFR. Among them, compound 29 showed excellent kinase inhibitory activity against EGFRL858R/T790M with an IC50 value of 0.55 ± 0.02 nM and potent anti-proliferative activity against H1975 cells with an IC50 value of 5.88 ± 0.07 nM. Moreover, the strong down-regulation effect of EGFR-mediated signaling pathways and the promotion of apoptosis in H1975 cells confirmed its potent antitumor activities. Compound 29 was also demonstrated with good ADME profile in various in vitro assays. Further in vivo studies confirmed that compound 29 could suppress the growth of xenograft tumors. These results verified that compound 29 would be a promising lead compound for targeting drug-resistant EGFR mutations.

Biomedical application of 2D nanomaterials in neuroscience.

Two-dimensional (2D) nanomaterials, such as graphene, black phosphorus and transition metal dichalcogenides, have attracted increasing attention in biology and biomedicine. Their high mechanical stiffness, excellent electrical conductivity, optical transparency, and biocompatibility have led to rapid advances. Neuroscience is a complex field with many challenges, such as nervous system is difficult to repair and regenerate, as well as the early diagnosis and treatment of neurological diseases are also challenged. This review mainly focuses on the application of 2D nanomaterials in neuroscience. Firstly, we introduced various types of 2D nanomaterials. Secondly, due to the repairment and regeneration of nerve is an important problem in the field of neuroscience, we summarized the studies of 2D nanomaterials applied in neural repairment and regeneration based on their unique physicochemical properties and excellent biocompatibility. We also discussed the potential of 2D nanomaterial-based synaptic devices to mimic connections among neurons in the human brain due to their low-power switching capabilities and high mobility of charge carriers. In addition, we also reviewed the potential clinical application of various 2D nanomaterials in diagnosing and treating neurodegenerative diseases, neurological system disorders, as well as glioma. Finally, we discussed the challenge and future directions of 2D nanomaterials in neuroscience.

Research progress in pharmacological effects of Aralia elata. / è¾½ä¸œæ¥¤æœ¨è¯ç†ä½œç”¨ç ”ç©¶è¿›å±•.

The traditional Chinese medicine Aralia elata (Miq.) Seem., also known as Aralia mandshurica, has the effect of "tonifying Qi and calming the mind, strengthening the essence and tonifying the kidneys, and dispelling wind and invigorating blood circulation". It is used in the treatment of neurasthenia, Yang deficiency and Qi deficiency, kidney Qi deficiency, spleen Yang deficiency, water-dampness stagnation, thirst, and bruises. Aralia elata saponins are the main components for the pharmacological effects. From the perspective of modern pharmacological science, Aralia elata has a wide range of effects, including anti-myocardial ischaemia and alleviation of secondary myocardium ischemic reperfusion injury by regulating ionic homeostasis, anti-tumor activity by inhibiting proliferation, promoting apoptosis and enhancing immunity, hypoglycemia and lipid lowering effects by regulating glucose and lipid metabolism, and hepato-protective, neuroprotective, anti-inflammatory/analgesic effects. The studies on pharmacological mechanisms of Aralia elata will be conducive to its development and application in the future. This article reviews the research progress of Aralia elata domestically and internationally in the last two decades and proposes new directions for further research.

Flavonoids from Citrus paradise cv. Changshan-huyou exerts protective effect on ischemia-induced cerebral injury in mice via inhibiting RhoA-ROCK2 signaling pathway. / èƒ¡æŸšé»„é ®é€šè¿‡æŠ‘åˆ¶RhoA-ROCK2信号通路发挥脑缺血保护作用.

OBJECTIVES: To investigate the protective effect and mechanism of total flavonoids from Citrus paradise cv. Changshan-huyou extracts (TFC) on oxygen-glucose deprivation (OGD) of primary neurons and chronic ischemia-induced cerebral injury in mice. METHODS: Primary hippocampal neurons of 18-day fetal rats were isolated and cultured for 1 week, then treated with 0.25, 0.50 and 1.00 mg/mL TFC. After oxygen-glucose deprivation for 1 h, cells were reperfused for 6 and 24 h, respectively. The cytoskeleton was observed by phalloidin staining. In animal study, 6-week ICR male mice were randomly divided into sham operation group, model group, low-dose (10 mg/kg), medium-dose (25 mg/kg) and high-dose (50 mg/kg) TFC treatment groups, with 20 mice in each group. After 3 weeks, chronic cerebral ischemia was induced by unilateral common carotid artery ligation in all groups except sham operation group. Mice were treated with different concentrations of TFC in the three TFC treatment groups for 4 weeks. Open field test, novel object recognition test and Morris water maze test were used to evaluate anxiety, learning and memory of these mice. Nissl, HE and Golgi stainings were used to detect neuronal degeneration and dendritic spine changes in the cortex and the hippocampus. The expression levels of Rho-associated kinase (ROCK) 2, LIM kinase (LIMK) 1, cofilin and its phosphorylation, as well as the expression of globular actin (G-actin) and filamentous actin (F-actin) protein in hippocampus of mice were detected by Western blotting. RESULTS: Neurons subjected to OGD showed that neurites displayed shortening and breakage; while treatment with TFC reversed OGD-induced neurite injury, especially in the 0.50 mg/mL TFC group. Compared with the sham operation group, the mice in the model group showed a significant decline in anxiety and cognitive ability (P<0.01), whereas treatment with TFC significantly reversed anxiety and cognitive deficits (P<0.05). Improvement in the medium-dose TFC group was the most obvious. Histopathological analysis indicated that the number of Nissl bodies and dendritic spines in hippocampus and cortex were decreased in the model group (all P<0.01). However, after treatment with medium dose of TFC, the number of Nissl bodies and dendritic spines (all P<0.05) was significantly recovered. Compared with the sham operation group, the phosphorylation level of ROCK2 in the brain tissue of the model group was significantly increased (P<0.05), while the phosphorylation levels of LIMK1 and cofilin were significantly decreased (P<0.05), and the relative content ratio of G-actin/F-actin was significantly increased (P<0.05). After administration of TFC, the phosphorylation level of ROCK2 in brain tissue of each group was significantly decreased (P<0.05), while the phosphorylation levels of LIMK1 and cofilin were significantly up-regulated (P<0.05) and the relative content ratio of G-actin/F-actin was significantly decreased (P<0.05). CONCLUSIONS: TFC protects from ischemia-induced cytoskeletal damage, reduces neuronal dendritic spine injury and protects mice against chronic cerebral ischemia through RhoA-ROCK2 signaling pathway, indicating that TFC might be a potential candidate for treatment of chronic ischemic cerebral injury.

Somatostatin interneurons inhibit excitatory transmission mediated by astrocytic GABAB and presynaptic GABAB and adenosine A1 receptors in the hippocampus.

GABAergic network activity has been established to be involved in numerous physiological processes and pathological conditions. Extensive studies have corroborated that GABAergic network activity regulates excitatory synaptic networks by activating presynaptic GABAB receptors (GABAB Rs). It is well documented that astrocytes express GABAB Rs and respond to GABAergic network activity. However, little is known about whether astrocytic GABAB Rs regulate excitatory synaptic transmission mediated by GABAergic network activity. To address this issue, we combined whole-cell recordings, optogenetics, calcium imaging, and pharmacological approaches to specifically activate hippocampal somatostatin-expressing interneurons (SOM-INs), a type of interneuron that targets pyramidal cell dendrites, while monitoring excitatory synaptic transmission in CA1 pyramidal cells. We found that optogenetic stimulation of SOM-INs increases astrocyte Ca2+ signaling via the activation of astrocytic GABAB Rs and GAT-3. SOM-INs depress excitatory neurotransmission by activating presynaptic GABAB Rs and astrocytic GABAB Rs, the latter inducing the release of ATP/adenosine. In turn, adenosine inhibits excitatory synaptic transmission by activating presynaptic adenosine A1 receptors (A1 Rs). Overall, our results reveal a novel mechanism that SOM-INs activation-induced synaptic depression is partially mediated by the activation of astrocytic GABAB Rs.

Miconazole exerts disease-modifying effects during epilepsy by suppressing neuroinflammation via NF-κB pathway and iNOS production.

Neuroinflammation contributes to the generation of epilepsy and has been proposed as an effective therapeutic target. Recent studies have uncovered the potential effects of the anti-fungal drug miconazole for treating various brain diseases by suppressing neuroinflammation but have not yet been studied in epilepsy. Here, we investigated the effects of different doses of miconazole (5, 20, 80 mg/kg) on seizure threshold, inflammatory cytokines release, and glial cells activation in the pilocarpine (PILO) pentylenetetrazole (PTZ), and intrahippocampal kainic acid (IHKA) models. We demonstrated that 5 and 20 mg/kg miconazole increased seizure threshold, but only 20 mg/kg miconazole reduced inflammatory cytokines release, glial cells activation, and morphological alteration during the early post-induction period (24 h, 3 days). We further investigated the effects of 20 mg/kg miconazole on epilepsy (4 weeks after KA injection). We found that miconazole significantly attenuated cytokines production, glial cells activation, microglial morphological changes, frequency and duration of recurrent hippocampal paroxysmal discharges (HPDs), and neuronal and synaptic damage in the hippocampus during epilepsy. In addition, miconazole suppressed the KA-induced activation of the NF-κB pathway and iNOS production. Our results indicated miconazole to be an effective drug for disease-modifying effects during epilepsy, which may act by attenuating neuroinflammation through the suppression of NF-κB activation and iNOS production. At appropriate doses, miconazole may be a safe and effective approved drug that can easily be repositioned for clinical practice.

Captopril alleviates epilepsy and cognitive impairment by attenuation of C3-mediated inflammation and synaptic phagocytosis.

Evidence from experimental and clinical studies implicates immuno-inflammatory responses as playing an important role in epilepsy-induced brain injury. Captopril, an angiotensin-converting enzyme inhibitor (ACEi), has previously been shown to suppress immuno-inflammatory responses in a variety of neurological diseases. However, the therapeutic potential of captopril on epilepsy remains unclear. In the present study, Sprague Dawley (SD) rats were intraperitoneally subjected to kainic acid (KA) to establish a status epilepticus. Captopril (50 mg/kg, i.p.) was administered daily following the KA administration from day 3 to 49. We found that captopril efficiently suppressed the KA-induced epilepsy, as measured by electroencephalography. Moreover, captopril ameliorated the epilepsy-induced cognitive deficits, with improved performance in the Morris water maze, Y-maze and novel objective test. RNA sequencing (RNA-seq) analysis indicated that captopril reversed a wide range of epilepsy-related biological processes, particularly the glial activation, complement system-mediated phagocytosis and the production of inflammatory factors. Interestingly, captopril suppressed the epilepsy-induced activation and abnormal contact between astrocytes and microglia. Immunohistochemical experiments demonstrated that captopril attenuated microglia-dependent synaptic remodeling presumably through C3-C3ar-mediated phagocytosis in the hippocampus. Finally, the above effects of captopril were partially blocked by an intranasal application of recombinant C3a (1.3 µg/kg/day). Our findings demonstrated that captopril reduced the occurrence of epilepsy and cognitive impairment by attenuation of inflammation and C3-mediated synaptic phagocytosis. This approach can easily be adapted to long-term efficacy and safety in clinical practice.

DYRK1A reinforces epithelial-mesenchymal transition and metastasis of hepatocellular carcinoma via cooperatively activating STAT3 and SMAD.

BACKGROUND: Hepatocellular carcinoma (HCC) accounts for the majority of liver cancer cases, while metastasis is considered the leading cause of HCC-related death. However, the currently available treatment strategies for efficient suppression of metastasis are limited. Therefore, novel therapeutic targets to inhibit metastasis and effectively treat HCC are urgently required. METHODS: Wound healing and Transwell assays were used to determine the migration and invasion abilities of HCC cells in vitro. Quantitative real-time PCR (qRT-PCR), protein array, immunofluorescence, and immunoprecipitation experiments were used to study the mechanism of DYRK1A-mediated metastasis. A tail vein metastasis model and H&E staining were utilized to assess metastatic potential in vivo. RESULTS: The results of the current study demonstrated that dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A) was upregulated in HCC tissues compared with normal liver tissues. Additionally, the level of DYRK1A was increased in primary HCC tissues of patients with metastasis compared with those of patients without metastasis, and DYRK1A overexpression correlated with worse outcomes in liver cancer patients. Gain- and loss-of-function studies suggested that DYRK1A enhanced the invasion and migration abilities of HCC cells by promoting epithelial-mesenchymal transition (EMT). Regarding the promoting effect of DYRK1A on cell invasion, the results showed that DYRK1A was coexpressed with TGF-ß/SMAD and STAT3 signalling components in clinical tumour samples obtained from patients with HCC. DYRK1A also activated TGF-ß/SMAD signalling by interacting with tuberous sclerosis 1 (TSC1) and enhanced metastasis of HCC cells by activating STAT3. Furthermore, DYRK1A promoted EMT by cooperatively activating STAT3/SMAD signalling. CONCLUSION: Overall, the present study not only uncovered the promoting effect of DYRK1A on HCC metastasis and revealed the mechanism but also provided a new approach to predict and treat metastatic HCC.

Regioselective Radical-Relay Sulfonylation/Cyclization Protocol to Sulfonylated Pyrrolidones under Transition-Metal-Free Conditions.

A simple and low-cost tandem sulfonylation/cyclization of 1,5-diene, aryldiazonium salt, and DABCO·(SO2)2 is disclosed. This base-promoted multicomponent reaction can provide a "green" and economic synthesis of sulfonylated pyrrolidones under transition-metal-free and moisture/oxygen-insensitive reaction conditions, thus delivering a wide range of sulfonylated pyrrolidones in moderate to high yields with excellent functional group compatibility. A plausible mechanism involving a radical process is proposed, which demonstrates highly chemoselective trapping of the aryl radical with "SO2" species, and a regioselective sulfonylation/cyclization protocol in this reaction.