Phospholipase C epsilon-1 (PLCE1) is a phospholipase C isoenzyme encoded by PLCE1 gene, and has more complicated molecular structure and function than other subtypes. Phospholipase C epsilon-1 is accepted the dual regulation by the upstream G proteins and GTP enzymes of Ras family. The downstream signal of PLCE1 is not only cause the Ca2+ flow and protein kinase C(PKC) activation, but also can be used as the GTP enzyme guanylic acid conversion factor of Ras superfamily, so as to regulate the expression of certain genes, adjusting cell growth and differentiation processes. PLCE1 plays a very important role in the signal transduction in the regulation of cell growth, differentiation, proliferation and apoptosis. Previous studies showed that phospholipase C epsilon-1 played an important role in the development of malignant tumors (especially the digestive tumors), heart disease, nephrotic syndrome and other diseases, but there are some questions about the mechanisms of PLCE1 involved in allergic rhinitis, this article will make an overview about PLCE1 promotes allergic rhinitis CD4+ T cells differentiate to Th2 cells by PKC-NF-κB pathway and Ras-MAPK pathway.
Apoptosis ; Calcium ; metabolism ; Cell Cycle ; Cell Differentiation ; physiology ; Cell Proliferation ; physiology ; Enzyme Activation ; Gene Expression ; Humans ; NF-kappa B ; Phosphoinositide Phospholipase C ; genetics ; physiology ; Protein Kinase C ; metabolism ; Rhinitis, Allergic ; enzymology ; Signal Transduction ; Th2 Cells ; cytology

Prior to fertilization sperm has to undergo an activation process known as capaciation, leading to the acrosome reaction. Till now, little is known about the mechanism for preventing premature capacitation in sperm although decapacitation factors from various sources have been thought to be involved. In this study, we report that NYD-SP27, an isoform of phospholipase C Zeta 1 (PLCZ1), is localized to the sperm acrosome in mouse and human spermatozoa by immunofluorescence using a specific antibody. Western blot and double staining analyses show NYD-SP27 becomes detached from sperm, as they undergo capacitation and acrosome reaction. The absence of HCO3-, a key factor in activating capacitation, from the capacitation-inducing medium prevents the loss of NYD-SP27 from sperm. The anti-NYD-SP27 antibody also prevents the loss of NYD-SP27 from sperm, reduced the number of capacitated sperm, inhibited the acrosome reaction induced by ATP and progesterone, and inhibited agonist-induced PLC-coupled Ca2+ mobilization in sperm, which can be mimicked by the PLC inhibitor, U73122. These data strongly suggest that NYD-SP27 is a physiological inhibitor of PLC that acts as an intrinsic decapacitation factor in sperm to prevent premature capacitation and acrosome reaction.
Acrosome ; drug effects ; metabolism ; Acrosome Reaction ; physiology ; Adult ; Animals ; Calcium ; metabolism ; Fluorescent Antibody Technique, Indirect ; Humans ; Immune Sera ; pharmacology ; Male ; Mice ; Middle Aged ; Phosphoinositide Phospholipase C ; immunology ; metabolism ; Sperm Capacitation ; drug effects ; physiology ; Spermatozoa ; drug effects ; metabolism

OBJECTIVETo study the expression of phospholipase C epsilon-1(PLCE1) and its clinical significance in gastric cancer.

METHODSSurgical specimens were collected from 125 patients who underwent radical gastrectomy between 2005 and 2007 in the Zhejiang Provincial Peoples' Hospital. Expression level of PLCE1 protein was measured by immunohistochemistry in these 125 surgical specimens, which included primary gastric cancer and matched adjacent normal gastric mucosa tissues, and then 41 pairs of above specimens were selected randomly to examine the expression level of PLCE1 mRNA by quantitative reverse transcription PCR(qRT-PCR).

RESULTSImmunohistochemistry and qRT-PCR showed that both protein and mRNA level of PLCE1 were up-regulated in gastric cancer compared with paired normal gastric mucosa. Univariate analysis demonstrated that the expression of PLCE1 was significantly associated with differentiation degree, invasion depth, lymph node metastasis, distant metastasis, and TNM stage (all P<0.01). The 5-year survival rate of positive PLCE1 group was significantly lower as compared to negative group (31.2% vs. 54.0%, P<0.01). However, the expression of PLCE1 was not an independent prognostic factor for gastric cancer (P>0.05).

CONCLUSIONSPLCE1 is up-regulated in gastric cancer, which is associated with the malignant biological behaviors of gastric cancer. High expression of PLCE1 suggests poor prognosis.

Biomarkers, Tumor ; analysis ; Gastrectomy ; Humans ; Immunohistochemistry ; Lymphatic Metastasis ; Neoplasm Staging ; Phosphoinositide Phospholipase C ; metabolism ; Prognosis ; RNA, Messenger ; Reverse Transcriptase Polymerase Chain Reaction ; Stomach Neoplasms ; enzymology ; pathology ; Survival Rate ; Up-Regulation

Nitric oxide (NO) produced by endothelial NO synthase (eNOS) plays an important role in vascular functions, including vasorelaxation. We here investigated the pharmacological effect of the natural product syringaresinol on vascular relaxation and eNOS-mediated NO production as well as its underlying biochemical mechanism in endothelial cells. Treatment of aortic rings from wild type, but not eNOS-/- mice, with syringaresinol induced endothelium-dependent relaxation, which was abolished by addition of the NOS inhibitor NG-monomethyl-L-arginine. Treatment of human endothelial cells and mouse aortic rings with syringaresinol increased NO production, which was correlated with eNOS phosphorylation via the activation of Akt and AMP kinase (AMPK) as well as elevation of intracellular Ca2+ levels. A phospholipase C (PLC) inhibitor blocked the increases in intracellular Ca2+ levels, AMPK-dependent eNOS phosphorylation, and NO production, but not Akt activation, in syringaresinol-treated endothelial cells. Syringaresinol-induced AMPK activation was inhibited by co-treatment with PLC inhibitor, Ca2+ chelator, calmodulin antagonist, and CaMKKbeta siRNA. This compound also increased eNOS dimerization, which was inhibited by a PLC inhibitor and a Ca2+-chelator. The chemicals that inhibit eNOS phosphorylation and dimerization attenuated vasorelaxation and cGMP production. These results suggest that syringaresinol induces vasorelaxation by enhancing NO production in endothelial cells via two distinct mechanisms, phosphatidylinositol 3-kinase/Akt- and PLC/Ca2+/CaMKKbeta-dependent eNOS phosphorylation and Ca2+-dependent eNOS dimerization.
Animals ; Aorta/*drug effects/physiology ; Enzyme Activation/drug effects ; Furans/*pharmacology ; Gene Deletion ; Human Umbilical Vein Endothelial Cells/drug effects/metabolism ; Humans ; Lignans/*pharmacology ; Mice ; Mice, Inbred C57BL ; Nitric Oxide/metabolism ; Nitric Oxide Synthase Type III/genetics/*metabolism ; Phosphatidylinositol 3-Kinases/metabolism ; Phosphoinositide Phospholipase C/metabolism ; Phosphorylation/drug effects ; Protein Multimerization/*drug effects ; Proto-Oncogene Proteins c-akt/metabolism ; Vasodilation/*drug effects

OBJECTIVEThe purpose of the present study was to observe the changes in CD4+CD25+Nrp1+Treg cells after irradiation with different doses and explore the possible molecular mechanisms involved.

METHODSICR mice and mouse lymphoma cell line (EL-4 cells) was used. The expressions of CD4, CD25, Nrp1, calcineurin and PKC-α were detected by flow cytometry. The expressions of TGF-β1, IL-10, PKA and cAMP were estimated with ELISA.

RESULTSAt 12 h after irradiation, the expression of Nrp1 increased significantly in 4.0 Gy group, compared with sham-irradiation group (P<0.05) in the spleen and thymus, respectively, when ICR mice received whole-body irradiation (WBI). Meanwhile the synthesis of Interleukin 10 (IL-10) and transforming growth factor-β1 (TGF-β1) increased significantly after high dose irradiation (HDR) (> or = 1.0 Gy). In addition, the expression of cAMP and PKA protein increased, while PKC-α, calcineurin decreased at 12h in thymus cells after 4.0 Gy X-irradiation. While TGF-β1 was clearly inhibited when the PLC-PIP2 signal pathway was stimulated or the cAMP-PKA signal pathway was blocked after 4.0 Gy X-irradiation, this did not limit the up-regulation of CD4+CD25+Nrp1+Treg cells after ionizing radiation.

CONCLUSIONThese results indicated that HDR might induce CD4+CD25+Nrp1+Treg cells production and stimulate TGF-β1 secretion by regulating signal molecules in mice.

Animals ; Calcineurin ; genetics ; metabolism ; Cyclic AMP ; metabolism ; Dose-Response Relationship, Radiation ; Female ; Gene Expression Regulation ; radiation effects ; Immunosuppression ; Interleukin-10 ; genetics ; metabolism ; Lymphocyte Subsets ; physiology ; Male ; Mice ; Neuropilin-1 ; genetics ; metabolism ; Phosphoinositide Phospholipase C ; genetics ; metabolism ; Protein Kinases ; genetics ; metabolism ; Signal Transduction ; Transforming Growth Factor beta ; genetics ; metabolism ; Whole-Body Irradiation ; adverse effects

Animals ; Carcinoma, Squamous Cell ; genetics ; Colorectal Neoplasms ; genetics ; metabolism ; Enzyme Activation ; Esophageal Neoplasms ; genetics ; Genome-Wide Association Study ; Head and Neck Neoplasms ; genetics ; Humans ; Neoplasms ; chemically induced ; enzymology ; genetics ; Phosphoinositide Phospholipase C ; chemistry ; genetics ; metabolism ; physiology ; Signal Transduction ; Skin Neoplasms ; chemically induced ; enzymology ; Stomach Neoplasms ; genetics ; Urinary Bladder Neoplasms ; metabolism ; pathology ; ras Proteins ; metabolism