成人白血病中PTPRO基因表达的研究

目的通过检测成人白血病中受体型蛋白酪氨酸磷酸酶-O(PTPRO)基因的表达水平,研究其在白血病发病中的作用及临床意义。方法将入选患者分为急性白血病(AL)初治组、完全缓解组(CR组)、慢性粒细胞白血病组(CML组)和正常对照组(NC组),Syber Green荧光定量PCR方法检测白血病和NC组骨髓单个核细胞(MNC)中PTPRO基因的表达。结果 (AL)初治组PTPRO表达水平低于CR组(P=0.028),更低于NC组(P<0.01);CML组低于CR组和NC组(P<0.05),与初治组比较差异无统计学意义(P=0.295),初治组中AML与ALL表达水平差异无统计学意义(P=0.158)。结论 PTPRO基因在成人白血病中表达水平明显降低,提示PTPRO基因在白血病的发生发展中可能具有一定作用。

Genes Expression Profile Difference in Peripheral Blood Between Esophageal Carcinoma Patients and Normal Subjects

Objective： To study the genes expression profile differences in the peripheral blood between esophageal carcinoma patients and normal subjects using the gene chip technique and screen out the esophageal early conceration associated genes. Methods： The total RNA was extracted and purified in the peripheral blood obtained from the patients with esophageal carcinoma and normal subjects. The first strand of cDNA was synthesized through retro-transcription and labeled with Cy5 and Cy3 fluorescence as probes. The mixed probes were hybridized with a piece of 4096 double dot human whole gene chip. The acquired image was analyzed by microarrav suite software using a digital computer, and the intensity of ttuorescence signal and its ratio were calculated. Results： A total of 92 genes were screened out and its expression difference was more than 2 times in the peripheral blood between the patients with esophageal carcinoma and normal subjects. Among these, the expression difference of 36 genes was more than 3 times. Two human urokinase plasminogen activator surface receptor （UPAR） genes, 80K-L protein gene, human protein tyrosine-phosphatase gent arid proto-oncogene protein mRNA were significantly up-regulated, while the collagen V type （α-2 gene was markedly down-regulated. Conclusion： 80K-L protein gene, tyrosinephophatase gene, proto-oncogene protein arid the collagen V type α-2 gene might be associated with the ontogenesis, development and its metastasis in the esophageal carcinoma. The UPAR gene may play important roles in the diagnosing the micrometastasis in the peripheral blood of esophageal carcinoma.

Progress in researches about focal adhesion kinase in gastrointestinal tract

Focal adhesion kinase(FAK)is a 125-kDa non-receptor protein tyrosine.Growth factors or the clustering of integrins facilitate the rapid phosphorylation of FAK at Tyr-397 and this in turn recruits Src-family protein tyrosine kinases,resulting in the phosphorylation of Tyr-576 and Tyr-577 in the FAK activation loop and full catalytic FAK activation.FAK plays a critical role in the biological processes of normal and cancer cells including the gastrointestinal tract.FAK also plays an important role in the restitution,cell survival and apoptosis and carcinogenesis of the gastrointestinal tract.FAK is over-expressed in cancer cells and its over-expression and elevated activities are associated with motility and invasion of cancer cells.FAK has been proposed as a potential target in cancer therapy.Small molecule inhibitors effectively inhibit the kinase activity of FAK and show a potent inhibitory effect for the proliferation and migration of tumor cells,indicating a high potential for application in cancer therapy.

Extraction and PTP1B inhibitory activity of bromophenols from the marine red alga Symphyocladia latiuscula

Previously, we had characterized several structurally interesting brominated phenols from the marine red alga Symphyocladia latiuscula collected from various sites. However, Phytochemical investigations on this species collected from the Weihai coastline of Shandong Province remains blank. Therefore, we characterized the chemical constituents of individuals of this species collected from the region. Eight bromophenols were isolated and identified. Using detailed spectroscopic techniques and comparisons with published data, these compounds were identified as 2,3-dibromo-4,5-dihydroxybenzyl methyl ether (1), 3,5-dibromo-4-hydroxybenzoic acid (2), 2,3,6-tribromo-4,5-dihydroxymethylbenzene (3), 2,3,6-tribromo-4,5-dihydroxybenzaldehyde (4), 2,3,6-tribromo-4,5-dihydroxybenzyl methyl ether (5), bis(2,3,6-tribromo-4,5-dihydroxyphenyl)methane (6), 1,2-bis(2,3,6-tribromo-4,5-dihydroxyphenyl)-ethane (7), and 1-(2,3,6-tribromo-4,5-dihydroxybenzyl)-pyrrolidin-2-one (8). Among these compounds, 1 and 2 were isolated for the first time from S. latiuscula. Each compound was evaluated on the ability to inhibit protein tyrosine phosphatase 1B (PTP1B), which is a potential therapeutic target in the treatment of type 2 diabetes. Bromophenols 5, 6, and 7 showed strong activities with IC50 values of 3.9, 4.3, and 3.5 μmol/L, respectively. This study provides further evidence that bromophenols are predominant among the chemical constituents of Symphyocladia, and that some of these compounds may be candidates for the development of anti-diabetes drugs.

Expression of Peptidylarginine Deiminase 4 and Protein Tyrosine Phosphatase Nonreceptor Type 22 in the Synovium of Collagen-Induced Arthritis Rats

Objective To study the expression level of peptidylarginine deiminase 4(PADI4) and protein tyrosine phosphatase nonreceptor type 22(PTPN22) in the synovium of rat model of collagen-induced arthritis, and to explore their possible therapeutic role in rheumatoid arthritis. Methods Thirty-two female Wistar rats weighing 100±20 g were randomly assigned into 3-week collagen-induced arthritis(CIA) model group(n=8), 4-week CIA model group(n=8), 6-week CIA model group(n=8), and the control group(n=8). The body weight changes of each group were recorded. The expression levels of PADI4 and PTPN22 were detected and compared by the methods of immunohistochemical staining and Western blot. Results Arthritis of rat began to form 14 days after sensitization and the joint swelling reached peak at 28 days. The weights of the rats slowly grew both in CIA model groups and the control group. Immunohistochemical staining results showed that the positive expression of PADI4 and PTPN22 was mainly located in cartilage peripheral mononuclear cells, the cytoplasm of infiltrated cells, and bone marrow cavity. There were significant differences in the optical density of PADI4 and PTPN22 among CIA model groups and the control group(PADI4, 0.2898±0.012, 0.2982±0.022, 0.2974±0.031, 0.2530±0.013 in 3-week CIA model, 4-week CIA model, 6-week CIA model and control groups; PTPN22, 0.2723±0.004, 0.2781±0.010, 0.2767±0.008, 0.2422±0.019; all P <0.05). The expression bands of PADI4 were observed in Western blot 3 weeks after initial immunization, the thickest in the 4th week, and decreased in the 6th week. The expression bands of PTPN2 were observed at all the time points, with no obvious time-dependent trend. Conclusions PADI4 and PTPN22 are obviously correlated with CIA in rat model. PADI4 is expressed at early stage of the disease, while the expression of PTPN22 sustains throughout the course.

Synthesis and protein tyrosine phosphatase 1B inhibition activities of two new synthetic bromophenols and their methoxy derivatives

3-bromo-4,5-bis（2,3-dibromo-4,5-dihydroxybenzyl）-l,2-benzenediol （1） is a natural bromophenol isolated from the red algae Rhodomela confervoides that exhibits significant inhibition against protein tyrosine phosphatase 1B （PTP1B）. Based on its activity, we synthesized two new synthetic bromophenols and their methoxy derivatives from vanillin using the structure of natural bromophenol 1 as a scaffold. The structures of these bromophenols were elucidated from H NMR, 13C NMR, and high resolution electron ionization mass spectrometry as 2,3-dibromo-1-（2＇-bromo-6＇-（3＂,4＂-dimethoxybenzyl）- 3 ＇,4 ＇-dimethoxybenzyl）-4,5 -dimethoxybenzene （2）, 2,3-dibromo- 1 -（2 ＇-bromo-6＇-（2 ＂-bromo-4＂,5 ＂-dimethoxy- benzyl）-3＇,4＇-dimethoxybenzyl）-4,5-dimethoxybenzene （3）, 3,4-dibromo-5-（2＇-bromo-6＇-（2＂-bromo-4＂,5＂- dihydroxybenzyl）-3＇,4＇-dihydroxybenzyl）pyrocatechol （4） and 3,4-dibromo-5-（2＇-bromo-6＇-（3＂,4＂- dihydroxybenzyl）-3＇,4＇-dihydroxybenzyl）pyrocatechol （5）. PTP1B inhibition activities of these compounds were evaluated using a colorimetric assay, and compounds 3 and 4 demonstrated interesting activity against PTP1B.

Bromophenols from Marine Algae with Potential Anti-Diabetic Activities

Marine algae contain various bromophenols with a variety of biological activities, including antimicrobial, anticancer, and anti-diabetic effects. Here, we briefly review the recent progress in researches on the biomaterials from marine algae, emphasizing the relationship between the structure and the potential anti-diabetic applications. Bromophenols from marine algae display their hyper- glycemic effects by inhibiting the activities of protein tyrosine phosphatase 1B, ct-glucosidase, as well as other mechanisms.

PTP1B在胃癌组织中表达及其对胃癌细胞系MKN28增殖、侵袭行为的影响

目的:研究蛋白质酪氨酸磷酸酶1B(PTP1B)在胃癌组织中的表达及其对胃癌细胞株MKN28增殖、侵袭的影响,为PTP1B作为靶点治疗胃癌提供理论基础。方法:采用Western blot检测PTP1B在39例胃癌组织及8例非癌胃组织中的表达情况,分析其与胃癌重要病理因素之间的关系,并通过构建靶向PTP1B的ShRNA的真核表达质粒Sh-PTP1B转染人胃癌细胞系MKN28,应用Western blot检测PTP1B蛋白表达,采用CCK-8、Transwell侵袭小室检测MKN28细胞增殖和侵袭。结果:PTP1B在胃癌组织的表达明显高于非癌胃组织,PTP1B表达与胃癌患者组织分化程度及TNM分期明显相关;胃癌细胞系MKN28中转染Sh-PTP1B后,细胞PTP1B蛋白表达明显减少,细胞增殖和侵袭明显抑制(P<0.05)。结论:PTP1B在胃癌的生长和侵袭过程中发挥重要作用,有可能成为靶向治疗胃癌的潜在靶点。

Synthesis of three bromophenols from red algae as PTP1B inhibitors

Bromophenols are a set of natural products widely distributed in seaweed, most of which exhibit interesting and useful biological activities. To develop a reliable and efficient synthetic route to these natural bromophenols, three of them, 3,4-dibromo-5-(2′-bromo-3′,4′- dihydroxy-6′-methoxymethyl- benzyl)-benzene-1,2-diol (compound 9), 3,4-dibromo-5-(2′-bromo-6′-ethoxy methyl-3′,4′-dihydroxybenzyl)- benzene-1,2-diol (compound 10), and 3-bromo-4-(3′-bromo-4′,5′-dihydroxy benzyl)-5-(ethoxymethyl)- benzene-1,2-diol (compound 14), isolated from red marine algae, have been synthesized in eight steps with an overall yield of 14.4%, 14.4%, and 18.2% respectively, via a practical approach employing bromination, Wolff-Kishner-Huang reduction and a Friedel-Crafts reaction as key steps. The protein tyrosine phosphatase 1B (PTP1B) inhibitory activities of the synthetic compounds were evaluated by the colorimetric assay. The results show that these compounds are moderate PTP1B inhibitors. The synthesis of these bromophenol derivatives makes in vivo studies of their structure-activity relationships and inhibition activity against PTP1B possible.

Characterization of DYRK2(dual-specificity tyrosine-phosphorylation-regulated kinase 2) from Zebrafish(Dario rerio)

Proteins of the DYRK(dual-specificity tyrosine-phosphorylation-regulated kinase) family are characterized by the presence of a conserved kinase domain and N-terminal DH box.DYRK2 is involved in regulating key developmental and cellular processes,such as neurogenesis,cell proliferation,cytokinesis,and cellular differentiation.Herein,we report that the ortholog of DYRK2 found in zebrafish shares about 70% identity with that of human,mouse,and chick.RT-PCR showed that DYRK2 is expressed maternally and zygotically.In-situ hybridization results show that DYRK2 is expressed in somite cells that will develop into muscles.Our results provide preliminary evidence for investigating the in-vivo function of DYRK2 in zebrafish muscle development.

Inhibition of protein tyrosine phosphatase 1B activity by triterpenes isolated from Aceriphyllum rossii

An organic layer prepared from the seed of Aceriphyllum rossii was studied to identify the active compounds for protein tyrosine phosphatase 1B（PTP1B） inhibition.Bioassay guided fractionation resulted in the isolation of PTP1B inhibitory activity of triterpenes（1-4）.These four compounds were identified as aceriphyllic acid C（1）,aceriphyllic acid D（2）,aceriphyllic acid E（3） and aceriphyllic acid F（4）.The isolated 1-4 compounds inhibited PTP1B with IC50 values ranged from（2.1±1.5） μmol/L to（11.2±2.5） μmol/L.Kinetic analysis of PTP1B inhibition by aceriphyllic acid C（1） and aceriphyllic acid D（2） suggested that oleanane-type triterpenes inhibited PTP1B activity in a mixed-type manner.

Inhibition of protein tyrosine phosphatase 1B by triterpenes isolated from Potentilla discolor Bge

Seven oleanene triterpenes were isolated from the roots of Potentilla discolor Bge and their structures were identified as 3-oxoolean-12-en-27-oic acid（1）, gypsogenic acid（2）, 3α-hydroxyolean-12-en-27-oic acid（3）, 3β-hydroxyolean-12-en-27-oic acid（4）, aceriphyllic acid A（5）, aceriphyllic acid A methyl ester（6）, and oleanolic acid（7）. Compounds 1–7 inhibited protein tyrosine phosphatase 1B（PTP1B） activity, with IC50 values ranging from（7.5±0.5） to（22.7±0.5） μmol/L. Among the isolates, compounds 1, 2, 3 and 7 from the Potentilla discolor Bge were found to exhibit selective PTP1 B inhibitory activity.

SENP1 regulates IFN-γ-STAT1 signaling throug STAT3-SOCS3 negative feedback loop

Interferon-γ （IFN-γ） triggers macrophage for inflammation response by activating the intracellular JAK-STAT1 signaling. Suppressor of cytokine signaling 1 （SOCS1） and protein tyrosine phosphatases can negatively modulate IFN-γ signaling. Here, we identify a novel negative feedback loop mediated by STAT3-SOCS3, which is tightly controlled by SENP1 via de-SUMOylation of protein tyrosine phosphatase 1B （PTPIB）, in IFN-y signaling. SENP1-deficient macrophages show defects in IFN-γ signaling and M1 macrophage activation. PTP1B in SENP1-deficient macrophages is highly SUMOylated, which reduces PTP1B-induced de-phosphorylation of STAT3. Activated STAT3 then suppresses STAT1 activation via SOCS3 induction in SENP1-deficient macro- phages. Accordingly, SENP1-deficient macrophages show reduced ability to resist Listerio rnonocytogenes infection. These results reveal a crucial role of SENP1-controlled STAT1 and STAT3 balance in rnacrophage polarization.

Inhibitory leukocyte immunoglobulin-like receptors in cancer development

Inhibitory leukocyte immunoglobulin-like receptors(LILRB1-5) signal through immunoreceptor tyrosine-based inhibitory motifs(ITIMs) in their intracellular domains and recruit phosphatases protein tyrosine phosphatase, non-receptor type 6(PTPN6, SHP-1), protein tyrosine phosphatase, non-receptor type 6(PTPN6, SHP-2), or Src homology 2 domain containing inositol phosphatase(SHIP) to negatively regulate immune cell activation. These receptors are known to play important regulatory roles in immune and neuronal functions. Recent studies demonstrated that several of these receptors are expressed by cancer cells. Importantly, they may directly regulate development, drug resistance, and relapse of cancer, and the activity of cancer stem cells. Although counterintuitive, these findings are consistent with the generally immune-suppressive and thus tumor-promoting roles of the inhibitory receptors in the immune system. This review focuses on the ligands, expression pattern, signaling, and function of LILRB family in the context of cancer development. Because inhibition of the signaling of certain LILRBs directly blocks cancer growth and stimulates immunity that may suppress tumorigenesis, but does not disturb normal development, LILRB signaling pathways may represent ideal targets for treating hematological malignancies and perhaps other tumors.

Protein tyrosine phosphatase 1B expression contributes to the development of breast cancer

The protein tyrosine phosphatase 1B（PTP1B）is an important regulator of metabolism.The relationship between PTP1B and tumors is quite complex.The purpose of this study is to explore the expression pattern and role of PTP1B in breast cancer.The expression of PTP1B was detected in 67 samples of breast cancer tissue by Western blot.Cell growth assay,Transwell migration assay,and Scratch motility assay were used to examine the proliferation and migration of MCF-7 with and without PTP1B.The total levels and phosphorylated levels of signal transduction and activator of transcription 3（STAT3）and the expression of C-C motif chemokine ligand 5（CCL5）were also examined by Western blot.PTP1B was overexpressed in over 70%of breast cancer tissues,correlating with patients with estrogen receptor（ER）-negative,progesterone receptor（PR）-negative,and human epidermal growth factor receptor 2（HER2）-positive tumors.The data also showed that both tumor size and lymph node metastasis were significantly higher in patients with a higher level of PTP1B.The proliferation and migration of MCF-7 cells were found to be inhibited after knocking down the gene of PTP1B.Our data also showed that PTP1B could up-regulate the dephosphorylated level of STAT3,which could increase the expression of CCL5.These phenomena indicated that PTP1B may play a crucial role in the development of breast cancer.

Reversible acetylation regulates vascular endothelial growth factor receptor-2 activity

The tyrosine kinase receptor vascular endothelial growth factor receptor 2 （VEG FR2） is a key regulator of angiogenesis. Here we show that VEGFR2 is acetylated in endothelial cells both at four lysine residues forming a dense cluster in the kinase insert domain and at a single lysine located in the receptor activation loop. These modifications are under dynamic control of the acetyltransferase p300 and two deacetyiases HDAC5 and HDAC6. We demonstrate that VEGFR2 acetylation essentially regulates receptor phosphorylation. In par- ticular, VEGFR2 acetylation significantly alters the kinetics of receptor phosphorylation after ligand binding, allowing receptor phos- phoryiation and intraceUular signaling upon proLonged stimulation with VEGF. Molecular dynamics simulations indicate that acetylation of the lysine in the activation loop contributes to the transition to an open active state, in which tyrosine phosphorylation is favored by better exposure of the kinase target residues. These findings indicate that post-translational modification by acetyiation is a critical mechanism that directLy affects VEGFR2 function.