Single-Cell Transcriptomic Atlas of Primate Ovarian Aging.

Molecular mechanisms of ovarian aging and female age-related fertility decline remain unclear. We surveyed the single-cell transcriptomic landscape of ovaries from young and aged non-human primates (NHPs) and identified seven ovarian cell types with distinct gene-expression signatures, including oocyte and six types of ovarian somatic cells. In-depth dissection of gene-expression dynamics of oocytes revealed four subtypes at sequential and stepwise developmental stages. Further analysis of cell-type-specific aging-associated transcriptional changes uncovered the disturbance of antioxidant signaling specific to early-stage oocytes and granulosa cells, indicative of oxidative damage as a crucial factor in ovarian functional decline with age. Additionally, inactivated antioxidative pathways, increased reactive oxygen species, and apoptosis were observed in granulosa cells from aged women. This study provides a comprehensive understanding of the cell-type-specific mechanisms underlying primate ovarian aging at single-cell resolution, revealing new diagnostic biomarkers and potential therapeutic targets for age-related human ovarian disorders.

A positive feedback circuit between RN7SK snRNA and m6A readers is essential for tumorigenesis.

N6-Methyladenosine (m6A) RNA modification, methylation at the N6 position of adenosine, plays critical roles in tumorigenesis. m6A readers recognize m6A modifications and thus act as key executors for the biological consequences of RNA methylation. However, knowledge about the regulatory mechanism(s) of m6A readers is extremely limited. In this study, RN7SK was identified as a small nuclear RNA that interacts with m6A readers. m6A readers recognized and facilitated secondary structure formation of m6A-modified RN7SK, which in turn prevented m6A reader mRNA degradation from exonucleases. Thus, a positive feedback circuit between RN7SK and m6A readers is established in tumor cells. From findings on the interaction with RN7SK, new m6A readers, such as EWS RNA binding protein 1 (EWSR1) and KH RNA binding domain containing, signal transduction-associated 1 (KHDRBS1), were identified and shown to boost Wnt/ß-catenin signaling and tumorigenesis by suppressing translation of Cullin1 (CUL1). Moreover, several Food and Drug Administration-approved small molecules were demonstrated to reduce RN7SK expression and inhibit tumorigenesis. Together, these findings reveal a common regulatory mechanism of m6A readers and indicate that targeting RN7SK has strong potential for tumor treatment.

Mental health and job stress of nurses in surgical system: what should we care.

BACKGROUND: Job stress has significant influence on the mental health of health care providers. The mental health and job stress of operating room nurses remain unclear. This study aimed to evaluate the mental health and job stress of nurses in surgical system in China, to provide evidences for clinical nurse management and care. METHODS: The nurses in the surgical system of our hospital were investigated by questionnaire in December 2022. The general information questionnaire, symptom check list 90 (SCL-90) and nurses' job stressor scale (NJSS) were used for data collection. Pearson correlation and logistic analysis were conducted to evaluate the related influencing factors. RESULTS: A total of 171 nurses in surgical system were investigated. The mental health level of nurses in operating room was low. The job pressure of the nurses in the operating room was in the middle level. The nursing profession and work, workload and distribution, working environment and resources, patient care, management and interpersonal relationship were all positively correlated with SCL-90 score of nurses in operating room. Logistic regression analysis indicated that age, year of work experience, professional ranks and titles both are the influencing factors of SCL-90 score and of nurses in operating room. CONCLUSIONS: The mental health of nurses in surgical system is affected by work pressure, ages, working years and professional titles. These factors should be considered in the psychological intervention of nurses in operating room in order to improve the health of clinical nurses.

Ratiometric electrochemical OR gate assay for NSCLC-derived exosomes.

Non-small cell lung cancer (NSCLC) is the most common pathological type of LC and ranks as the leading cause of cancer deaths. Circulating exosomes have emerged as a valuable biomarker for the diagnosis of NSCLC, while the performance of current electrochemical assays for exosome detection is constrained by unsatisfactory sensitivity and specificity. Here we integrated a ratiometric biosensor with an OR logic gate to form an assay for surface protein profiling of exosomes from clinical serum samples. By using the specific aptamers for recognition of clinically validated biomarkers (EpCAM and CEA), the assay enabled ultrasensitive detection of trace levels of NSCLC-derived exosomes in complex serum samples (15.1 particles µL-1 within a linear range of 102-108 particles µL-1). The assay outperformed the analysis of six serum biomarkers for the accurate diagnosis, staging, and prognosis of NSCLC, displaying a diagnostic sensitivity of 93.3% even at an early stage (Stage I). The assay provides an advanced tool for exosome quantification and facilitates exosome-based liquid biopsies for cancer management in clinics.

ISGylation of EMD promotes its interaction with PDHA to inhibit aerobic oxidation in lung adenocarcinoma.

Abnormal nuclear structure caused by dysregulation of skeletal proteins is a common phenomenon in tumour cells. However, how skeletal proteins promote tumorigenesis remains uncovered. Here, we revealed the mechanism by which skeletal protein Emerin (EMD) promoted glucose metabolism to induce lung adenocarcinoma (LUAD). Firstly, we identified that EMD was highly expressed and promoted the malignant phenotypes in LUAD. The high expression of EMD might be due to its low level of ubiquitination. Additionally, the ISGylation at lysine 37 of EMD inhibited lysine 36 ubiquitination and upregulated EMD stability. We further explored that EMD could inhibit aerobic oxidation and stimulate glycolysis. Mechanistically, via its ß-catenin interaction domain, EMD bound with PDHA, stimulated serine 293 and 300 phosphorylation and inhibited PDHA expression, facilitated glycolysis of glucose that should enter the aerobic oxidation pathway, and EMD ISGylation was essential for EMD-PDHA interaction. In clinical LUAD specimens, EMD was negatively associated with PDHA, while positively associated with EMD ISGylation, tumour stage and diameter. In LUAD with higher glucose level, EMD expression and ISGylation were higher. Collectively, EMD was a stimulator for LUAD by inhibiting aerobic oxidation via interacting with PDHA. Restricting cancer-promoting role of EMD might be helpful for LUAD treatment.

A Versatile Electrochemical Biosensor for the Detection of Circulating MicroRNA toward Non-Small Cell Lung Cancer Diagnosis.

Circulating microRNAs (miRNAs) can be used as noninvasive biomarkers and are also found circulating in body fluids such as blood. Dysregulated miRNA expression is associated with many diseases, including non-small cell lung cancer (NSCLC), and the miRNA assay is helpful in cancer diagnosis, prognosis, and monitoring. In this work, a versatile electrochemical biosensing system is developed for miRNA detection by DNAzyme-cleavage cycling amplification and hybridization chain reaction (HCR) amplification. With cleavage by Mn2+ targeted DNAzyme, DNA-walker can move along the predesigned DNA tracks and contribute to the transduction and enhancement of signals. For the electrochemical process, the formation of multiple G-quadruplex-incorporated long double-stranded DNA (dsDNA/G-quadruplex) structures is triggered through HCR amplification. The introduction of G-quadruplex allows sensitive measurement of miRNA down to 5.68 fM with good specificity. Furthermore, by profiling miRNA in the NSCLC cohort, this designed strategy shows high efficiency (area under the curve (AUC) of 0.879 using receiver operating characteristic (ROC) analysis) with the sensitivity of 80.0% for NSCLC early diagnosis (stage I). For the discrimination of NSCLC and benign disease, the assay displays an AUC of 0.907, superior to six clinically-acceptable protein tumor markers. Therefore, this platform holds promise in clinical application toward NSCLC diagnosis and prognosis.

Direct Benzylic C(sp3)-O Coupling with Alcohol via Site-Selective C(sp3)-H Cleavage at Room Temperature through a Remote Directing Group-Enabled Radical Relay Strategy.

Employing a low loading of the terminal oxidant, a remote directing group-enabled radical relay strategy for benzylic direct C(sp3)-H alkoxylation with alcohols at room temperature is developed. Satisfactory site-selectivity, chemoselectivity, and reaction scope are achieved under simple and mild conditions, and no ligand or additive is required. Mechanistic studies, ready conversions of the directing group, and other benzylic functionalizations currently under development in our laboratory further indicate the promising potentials of this remote directing group-enabled radical relay strategy.

Construction of Dual-Shell Mo2C/C Microsphere towards Efficient Electromagnetic Wave Absorption.

Carbon-based carbides have attracted tremendous attention for electromagnetic energy attenuation due to their adjustable dielectric properties, oxidation resistance, and good chemical stability. Herein, we reasonably regulate the growth of dopamine hydrochloride on the surface of the Mo-glycerate (Mo-GL) microsphere and then transform the resultant Mo-polydopamine (Mo-PD) microsphere into a dual-shell Mo2C/C (DS-Mo2C/C) microsphere in a high-temperature pyrolysis process under an inert atmosphere. It is found that the pyrolysis temperature plays an important role in the graphitization degree of the carbon matrix and internal architecture. The fabrication of a dual-shell structure can be propitious to the optimization of impedance matching, and the introduction of Mo2C nanoparticles also prompts the accumulation of polarization loss. When the pyrolysis temperature reaches 800 °C, the optimized composite of DS-Mo2C/C-800 exhibits good EM absorption performance in the frequency range of 2.0-18.0 GHz. DS-Mo2C/C-800's qualified bandwidth can reach 4.4 GHz at a matching thickness of 1.5 mm, and the integrated qualified bandwidth (QBW) even exceeds 14.5 GHz with a thickness range of 1.5-5.0 mm. The positive effects of the dual-shell structure and Mo2C nanoparticles on EM energy attenuation may render the DS-Mo2C/C microsphere as a promising candidate for lightweight and broad bandwidth EM absorption materials in the future.

RRM2 protects against ferroptosis and is a tumor biomarker for liver cancer.

BACKGROUND: Ferroptosis is the process of cell death triggered by lipid peroxides, and inhibition of glutathione (GSH) synthesis leads to ferroptosis. Liver cancer progression is closely linked to ferroptosis suppression. However, the mechanism by which inhibition of GSH synthesis suppresses potential ferroptosis of liver cancer cells and whether ferroptosis-related liver cancer biomarkers have a promising diagnostic value remain unknown. METHODS: Ribonucleotide reductase regulatory subunit M2 (RRM2) levels were measured using an enzyme linked immunosorbent assay (ELISA), quantitative RT-PCR (qPCR), immunoblotting (IB) and immunochemistry (IHC). Cell viability and cell death were measured by a CellTiter-Glo luminescent cell viability assay and staining with SYTOX Green followed by flow cytometry, respectively. Metabolites were measured using the indicated kits. The Interaction between glutathione synthetase (GSS) and RRM2 was measured using immunofluorescence (IF), co-immunoprecipitation (co-IP) and the proximal ligation assay (PLA). The diagnostic value was analyzed using the area under the receiver operating characteristic curve (AUC-ROC). Bioinformatics analysis was performed using the indicated database. RESULTS: RRM2 showed specifically elevated levels in liver cancer and inhibited ferroptosis by stimulating GSH synthesis via GSS. Mechanistically, phosphorylation of RRM2 at the Threonine 33 residue (T33) was maintained at normal levels to block the RRM2-GSS interaction and therefore protected RRM2 and GSS from further proteasome degradation. However, under ferroptotic stress, RRM2 was dephosphorylated at T33, thus the RRM2-GSS interaction was promoted. This resulted in the translocation of RRM2 and GSS to the proteasome for simultaneous degradation. Clinically, serum RRM2 was significantly associated with serum alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyl transpeptidase (γ-GT), albumin (ALB) and total bilirubin. The AUC-ROC for the combination of RRM2 with AFP was 0.947, with a sensitivity of 88.7% and a specificity of 97.0%, which indicates better diagnostic performance compared to either RRM2 or AFP alone. CONCLUSION: RRM2 exerts an anti-ferroptotic role in liver cancer cells by sustaining GSH synthesis. Serum RRM2 will be useful as a biomarker to evaluate the degree to which ferroptosis is suppressed and improve diagnostic efficiency for liver cancer.

Efficient metal-free aminoiodination of alkenes with N-fluorobenzenesulfonimide under mild conditions.

A novel efficient metal-free aminoiodination of alkenes with N-fluorobenzenesulfonimide (NFSI) through an iodonium intermediate under mild conditions with good regioselectivity and stereoselectivity is reported. Unlike transition-metal catalysed aminative bisfunctionalization with NFSI in which the oxidative addition of NFSI to transition-metals affords an electrophilic amino radical, the oxidation of anionic iodide by NFSI in situ generates an electrophilic iodine cation and an amino nucleophile to fulfil this efficient reaction. 2,2,6,6-Tetramethyl-piperidine-1-oxyl (TEMPO) could considerably promote this iodoamination at room temperature. A preliminary trial suggests that bromoamination could also be achieved under similar conditions.

Validity and reliability of a food frequency questionnaire for assessing dietary intake among Shanghai residents.

BACKGROUND: Few localized food frequency questionnaires (FFQ) have been developed and used in Chinese nutrition surveys despite China's large population and diverse dietary habits. METHOD: We analyzed data collected in two waves (six months apart) of the Shanghai Diet and Health Study in 2012-2013, from 1623 Shanghai residents (798 men and 825 women) older than 18 years. The results of 3-day 24-h dietary recalls (HDR) plus condiment weighing were used to evaluate the validity and reliability of the SDHS FFQ. RESULTS: The median and first and third quartiles for energy intake (in kcal) derived from the FFQ1 and FFQ2 were 1566.5 (1310.1-1869.6) and 1561.9 (1280.2-1838.4), respectively, of which protein (in g) was 54.3 (42.5-65.8) and 52.9 (42.4-64.5), fat (in g) was 49.8 (37.2-64.7) and 47.9 (34.9-61.9), and carbohydrates (in g) was 227.3 (180.8-277.9) and 228.1 (182.2-275.2) in the reliability analysis. The median and first and third quartiles for energy-intake differences between the FFQ1 and the 3-day 24-HDR with condiment weighing was 59.3 (- 255.5-341.6), of which protein was - 5.2 (- 18.7-7.8) and fat was - 11.2 (- 30.8-5.3). The adjusted Spearman's correlations were 0.33-0.77 for validity and 0.46-0.79 for reliability. The intra-class correlation coefficients exceeded 0.46 (validity) and 0.47 (reliability) for macronutrient intake. The consistency between the same and adjacent quartiles was approximately 80% for various nutrients. CONCLUSION: The reliability and comparative validity of the SDHS FFQ is similar to FFQs that are used worldwide.

Bufalin inhibits cell proliferation and migration of hepatocellular carcinoma cells via APOBEC3F induced intestinal immune network for IgA production signaling pathway.

OBJECTIVE: This study aimed to evaluate functions of APOBEC3F gene in biological process of hepatocellular carcinoma (HCC) and anti-tumor mechanisms of bufalin. METHODS: Effect of APOBEC3F and bufalin on cell proliferation and migration abilities were evaluated by CCK-8, wounding healing tests and transwell assays in SK-Hep1 and Bel-7404 cells. Bioinformatic analysis were also used to compare APOBEC3F expression levels, detect coexpressed genes and enrichment of pathways. RESULTS: APOBEC3F was overexpressed in tumor tissues compared to adjacent tissues in HCC patients. And, APOBEC3F promotes cell proliferation and migration in SK-Hep1 and Bel-7404 cells. Bufalin inhibits cell proliferation and migration and reduces APOBEC3F expression. GO and KEGG enrichment of APOBEC3F-coexpressed genes revealed that APOBEC3F might active intestinal immune network for IgA production signaling pathway, leading to malignant biological behaviors of HCC cells. Additionally, siAPOBEC3F could decrease pIgR, CCR9, CCR10 and CXCR4 protein levels. And, bufalin inhibits the pIgR, CCR9, CCR10 and CXCR4 protein expressions. CONCLUSIONS: Bufalin inhibits cell proliferation and migration of HCC cells via APOBEC3F induced intestinal immune network for IgA production signaling pathway.

NFSI-participated intermolecular aminoazidation of alkene through iron catalysis.

An iron-catalysed intermolecular vicinal aminoazidation of alkenes, using N-fluorobenzenesulfonimide (NFSI) and trimethylsilyl azide (TMSN3) as the imidating and azidating reagents, respectively, is described, which could potentially provide a valuable route toward diverse vicinal diamine derivatives of great significance in medicinal chemistry and organic synthesis. Such iron-catalysed aminative bisfunctionalization of alkenes with NFSI has not been reported yet. Comparing to previously employed copper or palladium catalysts, the iron catalyst, FeCl2, was demonstrated to be a good alternative for its comparable efficiency and broad alkene scope. Preliminary mechanistic study suggested that this iron-catalysed reaction is realized through radical processes.

Accelerated solvent extraction coupled to high-performance liquid chromatography-tandem mass spectrometry for simultaneous determination of 11 organophosphorus flame retardants in aquatic products.

BACKGROUND: A new method based on accelerated solvent extraction was developed for the extraction and determination of 11 organophosphorus flame retardants by using a high-performance liquid chromatography-tandem mass spectrometry technique. RESULTS: After optimization of the extraction temperature (80 °C), the extraction solvent (n-hexane), the flush volume (40%) and the static extraction time (4 min), all 11 organophosphorus flame retardants illustrated good linearities (R > 0.999). The limits of detection of the method ranged from 0.016 to 26.58 µg kg-1 in the different matrices. The recoveries were 90.4-111.2% with relative standard deviations 0.21-5.3% for the various aquatic products. CONCLUSION: The proposed method was applied successfully to detect 11 organophosphorus flame retardants in aquatic products, including grass carp, ribbon fish, mud fish, common eel, shrimp and frog. © 2018 Society of Chemical Industry.

Losartan loaded liposomes improve the antitumor efficacy of liposomal paclitaxel modified with pH sensitive peptides by inhibition of collagen in breast cancer.

The dense collagen network in tumors restricts the penetration of drugs into tumors. Free losartan could inhibit collagen, but it would cause hypotension at the dosage of 10 mg/kg/d. In this study, losartan was encapsulated in liposomes (LST-Lip) and the collagen inhibition ability of LST-Lip was investigated. Our results showed the blood pressure was not affected by LST-Lip at the dosage of 2.5 mg/kg every other day. The amount of Evans Blue in tumor in LST-Lip group was 1.98 times of that in control group. Confocal laser scanning microscopy images showed that prior injection of LST-Lip could inhibit collagen and further improve the tumorous accumulation of liposomes modified with TH peptides (AGYLLGHINLHHLAHL(Aib)HHIL-NH2) (TH-Lip) in 4T1 tumors. Compared with control group, the tumor inhibition rate of combined strategy of LST-Lip and paclitaxel loaded TH-Lip (PTX-TH-Lip) was 41.73%, while that of group only treated with PTX-TH-Lip was 14.94%. Masson's trichrome staining confirmed that collagen was inhibited in LST-Lip group. Thus, the administration of LST-Lip in advance could inhibit the collagen in tumors effectively and did not affect the blood pressure, then PTX-TH-Lip injected subsequently could exert enhanced antitumor efficacy. In conclusion, this combined strategy might be promising for breast cancer therapy.

DDQ-promoted direct C5-alkylation of oxazoles with alkylboronic acids via palladium-catalysed C-H bond activation.

A novel and concise C5-alkylation of oxazoles using alkylboronic acids as alkyl donors via Pd(ii)-catalysed C-H bond activation has been achieved in moderate to good yields with satisfactory functional group tolerance. Instead of commonly used BQ as a key promoter, DDQ was discovered to be a better additive that significantly promoted this alkylation. This efficient and advanced method represents the first C(sp2)-C(sp3) cross-coupling reaction at the C5-position of oxazoles, which is particularly attractive due to its potential applications in the late-stage functionalization of oxazole-containing bioactive molecules.

Cluster of differentiation 166 (CD166) regulated by phosphatidylinositide 3-Kinase (PI3K)/AKT signaling to exert its anti-apoptotic role via yes-associated protein (YAP) in liver cancer.

Cluster of differentiation 166 (CD166 or Alcam) is a cell surface molecule that can be greatly induced in liver cancer cells after serum deprivation, suggesting its role in influencing cell survival. However, whether and how CD166 acts as an anti-apoptotic regulator needs to be further investigated. Here, we report that gene silencing of CD166 promoted apoptosis via down-regulation of Bcl-2 in liver cancer cells. PI3K/AKT signaling was found to up-regulate CD166 expression independently of transcription. We also revealed that CD166 promoted both AKT expression and activity, thus providing a novel positive regulatory feedback between PI3K/AKT signaling and CD166. Moreover, Yes-associated protein (YAP) was identified as a CD166 downstream effecter, which can partly rescue CD166 knockdown-induced apoptosis and reduced in vivo cancer cell growth. Mechanically, CD166 modulated YAP expression and activity through at least two different ways, transcriptional regulation of YAP through cAMP-response element-binding protein and post-transcriptional control of YAP stability through inhibition to AMOT130. We also showed that CD9 enhanced CD166-mediated regulation of YAP via a mechanism involving facilitating CD166-CD166 homophilic interaction. Tissue microarray analysis revealed that CD166 and YAP were up-regulated and closely correlated in liver cancer samples, demonstrating the importance of their relationship. Taken together, this work summarizes a novel link between CD166 and YAP, explores the interplay among related important signaling pathways, and may lead to more effective therapeutic strategies for liver cancer.

Gensenoside Rb1 protects rat PC12 cells from oxidative stress-induced endoplasmic reticulum stress: the involvement of thioredoxin-1.

Oxidative stress plays an important role in many diseases and hydrogen peroxide (H2O2) plays a central role in the stress. Gensenoside Rb1 is the one of active ingredients in the traditional Chinese medicine Panax notoginseng. It has been reported that gensenoside Rb1 possesses various pharmacological activities. Here we report that gensenoside Rb1 exhibits potent protective effects against oxidative injury induced by H2O2 through inhibiting endoplasmic reticulum stress in PC12 cells. Cell viability assay demonstrated that incubation with H2O2 for 24 h led to a significant loss of cultured rat PC12 cells, and the cell viability was pronouncedly increased by pretreatment of gensenoside Rb1 for 24 h. H2O2-induced endoplasmic reticulum stress pathway was also suppressed after gensenoside Rb1 pretreatment, which was related with thioredoxin-1 (Trx-1) induction. Trx-1 siRNA abolished the protective effects of gensenoside Rb1. Our results of the present study demonstrate that gensenoside Rb1 shows a potent anti-oxidative effect on cultured PC12 cells by inducing Trx-1 expression.

[Clinical efficacy of structured institution-based teaching programme combined with family rehabilitation training in treatment of childhood autism].

OBJECTIVE: To investigate the clinical efficacy of a structured institution-based teaching programme combined with family rehabilitation training in the treatment of childhood autism. METHODS: One hundred children with autism were divided into a combination therapy group (n=50) and a control group (n=50). The children in the control group received a structured institution-based teaching programme, and the children in the combination therapy group received a family rehabilitation training besides the structured institution-based teaching programme. Comparisons were made between the two groups by the Autism Behavior Checklist (ABC) score, Autism Treatment Evaluation Checklist (ATEC) score, and Chinese version of Psychoeducational Profile (C-PEP) sore. RESULTS: After 12-months training, each dimension score and total score of ABC in the combination therapy group were all significantly lower than those in the control group (P<0.05). The combination therapy group had significantly lower dimension scores and total score of ATEC than the control group (P<0.05). Each dimension score and total score of C-PEP were significantly higher in the combination therapy than in the control group (P<0.05). CONCLUSIONS: As an effective treatment mode for childhood autism, structured institution-based teaching programme combined with family rehabilitation training is worthy of clinical promotion and application.

Impaired phosphorylation and ubiquitination by p70 S6 kinase (p70S6K) and Smad ubiquitination regulatory factor 1 (Smurf1) promote tribbles homolog 2 (TRIB2) stability and carcinogenic property in liver cancer.

Tribbles homolog 2 (TRIB2) is critical for both solid and non-solid malignancies. Recently, TRIB2 was identified as a liver cancer-specific Wnt/ß-catenin signaling downstream target and is functionally important for liver cancer cell survival and transformation. TRIB2 functions as a protein that interacts with E3 ubiquitin ligases and thereby modulates protein stability of downstream effectors. However, the regulation underlying TRIB2 protein stability per se has not yet been reported. In this study, we found that TRIB2 was up-regulated and exhibited high stability in liver cancer cells compared with other cells. We performed a structure-function analysis of TRIB2 and identified a domain (amino acids 1-5) at the N terminus that interacted with the E3 ubiquitin ligase Smurf1 and was critical for protein stability. Deletion of this domain extended TRIB2 half-life time accompanied with a more significant malignant property compared with wild type TRIB2. Furthermore, Smurf1-mediated ubiquitination required phosphorylation of TRIB2 by p70 S6 kinase (p70S6K) via another domain (amino acids 69-85) that is also essential for correct TRIB2 subcellular localization. Mutation of Ser-83 diminished p70S6K-induced phosphorylation of TRIB2. Moreover, the high stability of TRIB2 may be due to the fact that both p70S6K and Smurf1 were down-regulated and negatively correlated with TRIB2 expression in both liver cancer tissues and established liver cancer cell lines. Taken together, impaired phosphorylation and ubiquitination by p70S6K and Smurf1 increase the protein stability of TRIB2 in liver cancer and thus may be helpful in the development of diagnosis and treatment strategies against this malignant disease.