Differential Expression of KIF18B in Gastric Cancer and Its Role in Chemotherapy Sensitivity.

Gastric cancer (GC) is a main cause of cancer death in the world, and improving the chemotherapy sensitivity can enhance the chemotherapy efficacy of GC. The study objective is to explore the differential KIF18B expression in GC and its effect on GC chemotherapy sensitivity. The KIF18B expression in GC tissues and adjacent normal tissues was analyzed by real-time quantitative polymerase chain reaction. The relationship between differential KIF18B expression and different clinicopathological features was detected. It was found that KIF18B was highly expressed in GC tissues, and KIF18B expression was differential in patients with different clinicopathological features. The upregulation of KIF18B has a positive correlation with the poor therapeutic effect and high KIF18 was associated with lower 3-year overall survival and disease-free survival. The KIF18B-downregulated NCI-N87 cells were constructed and tested by cell counting kit-8 assay and colony formation. Cell migration and invasion were detected by Transwell assay. The xenograft tumor model was established to observe the effect of KIF18B on the efficacy of chemotherapy. The upregulation of KIF18B reduced the chemotherapy sensitivity of GC cells and enhanced their proliferation, migration, and invasion. Silencing KIF18B inhibited tumor growth and promoted chemotherapy efficacy in vivo. In summary, KIF18B inhibitor may have a potential function for improving the efficacy of chemotherapy in GC.

LncRNA AL645608.3 mediates malignant progression of acute myeloid leukemia.

OBJECTIVE: To investigate the role of lncRNA AL645608.3 in the malignant progression of acute myeloid leukemia (AML) cells and explore relevant molecular mechanisms. METHODS: The expression level of AL645608.3 was measured in AML cell lines (THP-1, HL-60, KG-1, and AML-193) via real-time quantitative polymerase chain reaction (RT-qPCR). Small hairpin RNA (shRNA) and open reading frame of AL645608.3 were cloned into lentiviral vectors and were infected into THP-1 and AML-193 cells. The expression of casitas B-lineage lymphoma (CBL), interferon regulatory factor 6 (IRF6), and interferon beta 1 (IFNB1) was detected through RT-qPCR, and western blot. Co-immunoprecipitation (Co-IP) on IRF6 was conducted. Matrix metalloprotease-9 (MMP-9) activity was evaluated via gelatin zymography assay. RESULTS: LncRNA AL645608.3 was expressed in the four AML cell lines (THP-1, HL-60, KG-1, and AML-193). Silencing AL645608.3 mitigated the expression of IRF6 and IFNB1 but elevated the expression of CBL in THP-1 cells. Oppositely, AL645608.3 overexpression up-regulated the expression of IRF6 and IFNB1 but decreased the expression of CBL in AML-193 cells. Co-IP results proved that AL645608.3 could directly mediate IRF6 activity in THP-1 and AML-193 cells. MMP-9 activity was decreased by AL645608.3 knockdown and was improved by AL645608.3 overexpression in AML-193 cells. CONCLUSION: AL645608.3 is expressed in different AML cell lines, and mediates the expression of CBL, IRF6, IFNB1, and MMP-9. These findings might deepen our comprehension of the molecular mechanisms underlying AML.

LINC00504 promotes the progression of acute myeloid leukemia by targeting MDM2.

Acute myeloid leukemia (AML) is a highly heterogeneous hematopoietic malignant tumor, accompanied by the abnormal cloning of myeloid hematopoietic stem cells, little is known about its etiological role and pathogenesis. We aimed to explore the effect and regulatory mechanism of LINC00504 on the malignant phenotypes of AML cells. In this study, LINC00504 levels in AML tissues or cells were ascertained by PCR. RNA pull-down and RIP assays were conducted to verify the combination of LINC00504 and MDM2. Cell proliferation was detected by CCK-8 and BrdU assays, apoptosis was checked by flow cytometry, and glycolytic metabolism levels were detected by ELISA analysis. The expressions of MDM2, Ki-67, HK2, cleaved caspase-3, and p53 were detected by western blotting and immunohistochemistry. A xenograft tumor model was used to detect the role of LINC00504 in vivo. Results showed that LINC00504 was highly expressed in AML and its high expression was related to clinicopathological features in AML patients. LINC00504 knockdown significantly inhibited the proliferation and glycolysis, while inducing apoptosis of AML cells. Meanwhile, LINC00504 downregulation also exerted a significant alleviating effect on AML cell growth in vivo. In addition, LINC00504 could bind to MDM2 protein and positively regulate its expression. Overexpression of LINC00504 promoted the malignant phenotypes of AML cells and partially reversed the inhibitory effects of LINC00504 knockdown on AML progression. In conclusion, LINC00504 facilitated AML cell proliferation and suppressed apoptosis through upregulating MDM2 expression, suggesting that LINC00504 may serve as a prognostic marker and therapeutic target in patients with AML.

Tracing type 1 diabetic Tibet miniature pig's bone marrow mesenchymal stem cells in vitro by magnetic resonance imaging (1).

BACKGROUND: Traditional cell-tracking methods fail to meet the needs of preclinical or clinical research. Thus, the aim of the present study was to establish a new method of double labeling bone marrow mesenchymal stem cells (BMSCs) from type 1 diabetic (T1D) minipigs with super-paramagnetic iron oxide (SPIO) and enhanced green fluorescent protein (eGFP) and tracing them using MRI in vitro. METHODS: Isolated BMSCs from T1D minipigs were labeled with eGFP and different concentrations of SPIO. The effects of lentivirus (LV)-eGFP transfection and SPIO on the viability and growth curves of BMSCs were determined by Trypan blue exclusion, the 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide assay and flow cytometry. Cellular ultrastructure was evaluated by transmission electron microscopy. Magnetic resonance imaging was used to evaluate BMSCs labeled with SPIO-eGFP complexes 6 weeks after labeling. RESULTS: Expression of eGFP in BMSCs peaked 96 h after transfection with LV-eGFP. Prussian blue staining revealed scattered blue granules in the cytoplasm of SPIO-labeled cells. Transmission electron microscopy revealed that the dense granules aggregated mainly in secondary lysosomes. On MRI, T2* -weighted imaging was far more sensitive for SPIO-labeled BMSCs than other image sequences 3 and 6 weeks after the cells had been labeled with SPIO-eGFP. CONCLUSIONS: We have developed a relatively simple and safe method for double labeling of BMSCs from T1D minipigs using SPIO and LV-eGFP and tracing them in vitro by MRI for 6 weeks.

[Incidence and related risk factors of diabetic ketoacidosis in Guangdong type 1 diabetics].

OBJECTIVE: To determine the incidence and the predictors of diabetes ketoacidosis (DKA) in Chinese type 1 diabetics so as to lay a foundation for better prevention and treatment. METHODS: For this cross-sectional study, a total of 611 patients with established type 1 diabetes between August 6, 2010 and March 31, 2012 were recruited from 16 hospitals in Guangdong Province. And 491 of them were over 18 years old. A data entry form was used to collect the patient information on demographics, medical history, acute/chronic complications, smoking/drinking status, diet, exercise, physical examination and treatment, etc. Hemoglobin A1c (HbA1c) and stimulated C peptide levels were centrally measured. The incidence rate of diabetic ketoacidosis (DKA) was calculated at events per 100 patient-years. To determine the predictors of DKA, Poisson's regression model was used for analysis. And backward stepwise logistic regression analysis was performed to identify the predictors of DKA recurrence. The protocol and informed consent form were approved by Ethics Committee of Third Affiliated Hospital, Sun Yat-sen University. Written informed consent was obtained from patients (age > 18 years) or their legal guardians (age < 18 years). RESULTS: Among them, 53.7% were females. The mean age was 27.8 years (range: 19.5 - 37.3). The age of onset was 22.7 (14.0 - 31.4) years old and disease duration 4.3 (1.7 - 7.9) years. Overweight and obese patients accounted for 10.8% and 1.0% respectively. Among them, the self-monitoring frequency of blood glucose was 0.4 (0.1 - 1.4) times per day. Overall, 26.4% patients reached the target of age-specific HbA1c values. The overall incidence of DKA was 26.4 per 100 patient-years. Significant predictors of DKA in the Poisson regression model were females (RR = 2.12), medical insurance claiming percentage below 50% (RR = 1.84), uncontrolled diet (never controlled diet vs. usually controlled diet, RR = 1.76), smoking (RR = 2.18) as well as worse glycemic control (HbA1c per 1.0% increment, RR = 1.15). Totally, 34.4% of DKA episodes occurred in 3.8% of type 1 diabetics with recurrent events (no less than 2 episodes). The recurrence of DKA was associated with females (RR = 10.56), smoking (RR = 6.99), worse beta cell function (stimulated C peptide per 100 pmol/L decrement, RR = 4.88) and worse glycemic control (HbA1c per 1.0% increment, RR = 1.16). CONCLUSION: There is a high incidence of DKA in Chinese type 1 diabetics. And it is recurrent in high-risk patients. Comprehensive management should be offered to control modifiable risk factors in these patients.

[Association of TNF-1031T/C and clinical efficacy of insulin therapy in newly diagnosed type 2 diabetics].

OBJECTIVE: Tumor necrosis factor (TNF ) locus has been a long-standing type 2 diabetes (T2D) candidate gene. Few studies have been conducted on TNF SNP (single nucleotide polymorphism) as rs1799964 (T-1031C), rs1800630 (A-863C) and rs1799724 (C-857T) in T2D. The purpose of this study is to examine the association of TNF SNP and T2D in a case control study and further explore whether these SNPs influence the clinical efficacy of insulin therapy. METHODS: A total of 109 newly diagnosed type 2 diabetics and 168 healthy individuals were recruited. Three tag SNPs (rs1799964 (T-1031C), rs1800630 (A-863C), rs1799724 (C-857T)) were selected across the TNF locus and polymerase chain reaction (PCR) directed sequencing was performed. The patients received Lispro 25 twice daily to achieve glycemic control and they were followed up for 1 year. Plasma glucose level, lipid profile, homeostatic model assessment for insulin resistance (HOMA-IR) and homeostatic model assessment for beta-cell function (HOMA-ß) were compared among groups with different haplotypes of SNPs. RESULTS: Haplotype of TNF-1031C-863C-857C increased the risk of T2D (OR = 2.7, P < 0.05) . Comparing with homozygote of TNF-1031T-863C-857C diabetics (TCC), those carrying CCC allele had higher fasting serum insulin (16.1(12.0-20.3) mU/L) and HOMA-IR (lnHOMA-IR 1.8 ± 0.4) levels (TCC group: 10.6(8.1-14.3) mU/L and 1.42 ± 0.54 respectively, P < 0.05)). One-year insulin treatment decreased HbA1c effectively in both TCC and CCC groups (P < 0.05). However, higher HOMA-IR was still observed in CCC group than that of TCC after normoglycemia (lnHOMA-IR: 2.5(0.9-3.9) vs 1.1(0.8-1.8) respectively, P < 0.05) . Moreover HOMA-ß showed no significant improvement in CCC group as it was in TCC group by the endpoint of follow-up. CONCLUSIONS: TNF-1031C-863C-857C is a risk haplotype for T2D. CCC carrying patients failed to achieve HOMA-ß improvement. And it might be due to increased endogenous HbOMA-IR level comparing with TCC homozygote.

Exchange of a nuclear corepressor between NF-kappaB and CREB mediates inhibition of phosphoenolpyruvate carboxykinase transcription by NF-kappaB.

BACKGROUND: NF-kappaB p65 was shown to inhibit transcription of phosphoenolpyruvate carboxykinase (PEPCK), a rate-limiting enzyme in gluconeogenesis in the liver. To understand the mechanism of action of NF-kappaB p65, we investigated the nuclear receptor corepressor in the regulation of PEPCK transcription. METHODS: Rat H4IIE cells, human hepatoma HepG2 cells and human embryo kidney (HEK) 293 cells were used in this study. The transcriptional activity of a rat PEPCK gene promoter (-490/+100) was analyzed in HepG2 cells, a HepG2 super suppressor IkBalpha (ssIkBalpha) stable cell line, and HEK 293 cells. The effects of p65 and ssIkBalpha on a rat PEPCK gene promoter were observed using the PEPCK luciferase reporter system. The interaction of the cAMP-response- element-binding (CREB) protein, histone deacetylase 3 (HDAC3) and silencing mediator for retinoic and thyroid hormone receptors (SMRT) with the PEPCK gene promoter were investigated using the chromatin immunoprecipitation (ChIP) assay. p65 cotransfection and RNAi-mediated gene knockdown were used to determine the corepressor involved in the inhibition of PEPCK by NF-kappaB p65 and the transcriptional regulation of CREB by NF-kappaB p65. RESULTS: NF-kappaB p65 inhibited PEPCK expression and the inhibition was blocked by ssIkBalpha. The inhibitory effect of p65 was completely blocked in a HepG2 stable cell line in which ssIkBalpha was expressed. HDAC3 or SMRT knockdown led to a significant up-regulation of PEPCK reporter activity in the presence of p65 cotransfection. In the ChIP assay the interaction of HDAC3 and SMRT with the PEPCK gene promoter was induced by p65 activation, but the CREB signal was reduced. Transcriptional activity of CREB was inhibited by NF-kappaB p65 cotransfection. The inhibitory effect of NF-kappaB p65 was blocked by HDAC3 RNAi or SMRT RNAi. CONCLUSIONS: The study showed that the inhibition of PEPCK by NF-kappaB p65 was dependent on HDAC3 and SMRT, which form a nuclear corepressor complex for transcriptional inhibition. The transcription factors NF-kappaB p65 and CREB share the same corepressor HDAC3-SMRT, and the corepressor exchange leads to inhibition of PEPCK gene transcription by NF-kappaB p65.

[Changes of serum angiogenesis in patients with chronic mountain sickness].

AIM: The clinical manifestation of chronic mountain sickness (CMS) is polycythemia, pulmonary hypertension and mionectic blood. However, the pathogenesis of it is not identified now. So it is necessary to investigate the effects of the angiogenic growth factors on the pathophysiologic development of CMS. METHODS: The serum levels of basic fibroblast growth factor (bFGF), platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) in 13 healthy Tibetan natives (Native), 17 healthy people in Xining (control group) and 35 CMS patients were determined by quantitative sandwich enzyme immunoassay. Meanwhile, the levels of Hb, Hct and SaO2 were determined. RESULTS: The serum levels of bFGF (107.26 +/- 7.86) ng/L, PDGF (630.18 +/- 9.89) ng/L and VEGF (543.74 +/- 6.76) ng/L in CMS were significantly higher than those in Natives (37.01 +/- 9.16; 292.16 +/- 6.88; 125.51 +/- 7.26) ng/L, and in control group (40.58 +/- 5.34; 287.68 +/- 8.33; 76.26 +/- 4.60) ng/L, respectively (P < 0.01). There was no difference between the natives and the control group in bFGF and PDGF (P > 0.05), while there was predominant difference between the Natives and the control group in VEGF (P < 0.01). There was a predominant positive correlation between the serum levels of bFGF, PDGF or VEGF and hemoglobin concentrations in CMS respectively (P < 0.01). And there were positive relations between angiogenic growth factors each other. CONCLUSION: The serum levels of bFGF, PDGF and VEGF in patients with CMS significantly increase, these angiogenic growth factors may play important role on the pathophysiologic development of CMS; the VEGF level likely contributes to the adaptation to plateau hypoxia in healthy Tibetan natives; the elevated bFGF, PDGF and VEGF levels are likely associated with excessive erythropoiesis in CMS.

[The clinical characteristics of primary intracranial germinoma].

OBJECTIVE: To analyse the clinical characteristics of intracranial germinoma. METHODS: Retrospective analysis was applied to study the clinical characteristics of 26 intracranial germ cell tumor patients admitted to our hospital during 1991-2003. The clinical, biochemical and imaging profiles including human chorionic gonadotropin-beta, alphafetoprotein, MRI and CT as well as treatments were analysed. RESULTS: 26 intracranial germ cell tumor patients were admitted to our hospital during 1991-2003, accounting for 0.9% of all intracranial tumors (3020 cases) at the same time. Among these patients 19 cases (73.1%) were primary intracranial germinoma, 9 patients (47.4%) were female and 10 patients (52.6%) were male. 13 patients (68.4%) were younger than 20 years. 14 patients (73.7%) had headache, vomiting and nausea, 8 patients (42.1%) had diabetes insipidus, 5 patients (26.3%) had hypopituitarism. 9 patients' tumors (47.3%) were in pine region, 7 patients' tumors (38.8%) were in sellar region. 14 patients (73.7%) were treated wit radiotherapy and all of them were discharged with good condition. 10 patients were treated with operation (7 patients accepted radiotherapy after operation) and 2 of them died after operation. CONCLUSIONS: Intracranial germinoma mainly affects female children and adolescents, pine and suprasellar regions are the commonly involved regions, the most common manifestations of intracranial germinoma are headache, vomiting, nausea, diabetes insipidus and hypopituitarism. Radiotherapy has good efficacy in the treatment of intracranial germinoma.