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Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes. All VEGF-receptors have seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular split tyrosine kinase domain. VEGFR-2 has a lower affinity for VEGF than the Flt-1 receptor, but a higher signaling activity. Mitogenic activity in endothelial cells is mainly mediated by VEGFR-2 leading to their proliferation.
Differential splicing of the flt-1 gene leads to the formation of a secreted, soluble variant of VEGFR-1 (sVEGFR-1). No naturally occuring, secreted forms of VEGFR-2 have so far been reported. The binding of VEGF165 to VEGFR-2 is dependent on heparin.

Ephrin-B2 belongs to the ephrin (EPH) family. The ephrins and EPH-related receptors contain the largest subfamily of receptor protein-tyrosine kinases and have been associated with mediating developmental events, particularly in the nervous system and in erythropoiesis. Based upon their structures and sequence relationships, ephrins are allocated into the ephrin-A (EFNA) class, which are anchored to the membrane by a glycosylphosphatidylinositol linkage, and the ephrin-B (EFNB) class, which are transmembrane proteins. Ephrin-B2 binds to the EPHB4 and EPHA3 receptors.

EFNB1 is a member of the Eph family. The cell-surface proteins Ephrins split into two groups, ephrin-A and ephrin-B, based on their structure and function and perform as ligands for Eph receptors. The transmembrane EFNB1 proteins have conserved cytoplasmic tyrosine residues that are phosphorylated upon interaction with an EphB receptor. In addition, EFNB1 transduces outside-in signals by C-terminal protein interfaces which influence integrin-mediated cell attachment and migration.

Cyclin-dependent kinase 2 (CDK2) belongs the Ser/Thr protein kinase family. CDK2 is highly parallel to the gene products of S. cerevisiae cdc28, and S. pombe cdc2. CDK2 is a catalytic subunit of the cyclin-dependent protein kinase complex, whose activity is limited to the G1-S phase, and is vital for cell cycle G1/S phase transition. The CDK2 protein associates with and is regulated by the regulatory subunits of the complex including cyclin A or E, CDK inhibitor p21Cip1 (CDKN1A) and p27Kip1 (CDKN1B). CDK2 activity is also regulated by protein phosphorylation.

Astyrosine-protein phosphatase non-receptor type 11 isoform 2 (PTPN11), is a member of the protein-tyrosine phosphatase family, non-receptor class 2 subfamily. PTPN11 takes part in signal transduction from the cell surface to the nucleus downstream of various cytosolic protein tyrosine kinases as well as receptors. PTPN11 deficient cells have poor mobility due to excessive phosphorylation of FAK as well as other proteins which interfere with the rotation of cell attachment points in the focal adhesion complex.

Kallikrein-3 (KLK3) is a part of the kallikrein-related peptidase family. Kallikreins are a subgroup of serine proteases having various physiological functions. Numerous kallikreins take part in carcinogenesis and some may be prospective cancer and other disease biomarkers. Kallikrein-3 is 1 of the 15 kallikrein subfamily members located in a cluster on chromosome 19 and is a protease present in seminal plasma. KLK3 hydrolyzes semenogelin-1 consequently leading to the liquefaction of the seminal coagulum. KLK3 acts normally in the liquefaction of seminal coagulum, probably by hydrolysis of the high molecular mass seminal vesicle protein. Serum level of the KLK3 protein, called PSA in the clinical setting, is beneficial in the diagnosis and monitoring of prostatic carcinoma.

Mitogen-Activated Protein Kinase 8, also known as MAPK8, is a part of the MAP kinase family. MAP kinases an integration point for multiple biochemical signals which take part in a various cellular processes. MAPK8 is a protein coding gene which is also involved in UV radiation induced apoptosis that is associated to cytochrom c-mediated cell death pathway.

EFNB1 is a member of the Eph family. The cell-surface proteins Ephrins split into two groups, ephrin-A and ephrin-B, based on their structure and function and perform as ligands for Eph receptors. The transmembrane EFNB1 proteins have conserved cytoplasmic tyrosine residues that are phosphorylated upon interaction with an EphB receptor. In addition, EFNB1 transduces outside-in signals by C-terminal protein interfaces which influence integrin-mediated cell attachment and migration.

Ephrin-B3 (EFNB3) which belongs to the ephrin gene family is essential in brain development as well as in its maintenance. EFNB3 binds to, and induces the collapse of, commissural axons/growth cones in vitro. EFNB3 loosely binds Eph receptors located on bordering cells, leading to contact-dependent bidirectional signaling into neighboring cells. The EPH and EPH-related receptors comprise the largest subfamily of receptor protein-tyrosine kinases and are implicated in mediating developmental events, mostly in the nervous system.

Signal transducer and activator of transcription 3 isoform 1, STAT3, ADMIO, DMIO1, APRF, HIES.

Ribokinase (RBKS) is a member of the pfkB family of carbohydrate kinases. Ribokinase phosphorylates ribose to form ribose-5-phosphate in the presence of ATP and magnesium as a first step in ribose metabolism.

O-Sialoglycoprotein Endopeptidase, also known as OSGEP is a member of the KAE1 / TsaD family. OSGEP is essential for the formation of threonylcarbamoyl group on adenosine at position 37 (t6A37) in tRNAs which read codons beginning with adenine. OSGEP take a direct catalytic part in the above reaction, however other proteins of the complex are required to fulfill this activity.

Protein Tyrosine Phosphatase Type IVA Member 3 (PTP4A3) is a member of a small class of prenylated protein tyrosine phosphatases (PTPs) which remove phosphate modifications from tyrosine residues on proteins. PTP4A3 enhances cell proliferation, cell motility and invasive activity. PTP4A3 functions as a protein tyrosine phosphatase which stimulates progression from G1 into S phase during mitosis. PTP4A3 is mostly expressed in cardiomyocytes and skeletal muscle; it is also found in the pancreas.
PTP4A3 is always overexpressed in colon cancer metastasis. PTP4A3 is notably overexpressed in liver metastasis of colorectal cancer. High levels of PTP4A3 expression are linked to tumorigenesis and metastasis; therefore it is overexpressed in metastatic colorectal, ovarian, liver and skin cancers. PTP4A3 may be involved in the progression of cardiac hypertrophy by inhibiting intracellular calcium mobilization in response to angiotensin II. PTP4A3 is inhibited by sodium orthovanadate and peroxovanadium compounds.

YWHAH belongs to the 14-3-3 family of proteins which mediate signal transduction by binding to phosphoserine-containing proteins. 14-3-3 ETA is found in plants and mammals, and there is 99% identity to the mouse, rat and bovine orthologs. YWHAH gene contains a 7 base pair repeat sequence in its 5' UTR, and changes in the number of this repeat has been associated with early-onset schizophrenia.
14-3-3 eta is specific to the site of joint inflammation.
14-3-3 proteins are colocalized with Lewy bodies in Parkinson disease, though there is no specific staining for the 14-3-3 eta subunit.
There are 3 different isoforms types of 14-3-3: Beta, Gamma and ETA that are DAL-1/Protein 4.1B-binding proteins.

SKP1 is a F-box enzyme which functions as a substrate recognition component of the SCF ubiquitin ligase complex which controls the ubiquitination of proteins involved in cell cycle progression, signal transduction and transcription. SKP1 binds to proteins containing an F-box motif, such as cyclin F, S-phase kinase-associated protein 2, and other regulatory proteins involved in ubiquitin dependent proteolysis. SKP1 takes part in the control of beta-catenin levels and the activity of beta-catenin dependent TCF transcription factors. SKP1 serves as an adapter that links the F-box protein to CUL1 in the SCF complex.

CK-MB Type II possesses the naturally occurring carboxy-terminal amino acid lysine.
This occurs during a myocardial infarct (MI or heart attack) when CK-MB Type II is released from damaged heart muscle, and the C-terminal lysine is cleaved in the blood stream, thus creating CK-MB Type I. This difference can be exploited in diagnosis of an MI.

Kallikrein-3 (KLK3) belongs to the kallikrein-related peptidase family. Kallikreins are a subgroup of serine proteases having various physiological functions. Numerous kallikreins are involved in carcinogenesis and some may be prospective cancer and other disease biomarkers. Kallikrein-3 is 1 of the 15 kallikrein subfamily members located in a cluster on chromosome 19 and is a protease present in seminal plasma. KLK3 hydrolyzes semenogelin-1 consequently leading to the liquefaction of the seminal coagulum. KLK3 is assumed to act normally in the liquefaction of seminal coagulum, probably by hydrolysis of the high molecular mass seminal vesicle protein. Serum level of the KLK3 protein, called PSA in the clinical setting, is beneficial in the diagnosis and monitoring of prostatic carcinoma.

PGK2, also known as Phosphoglycerate kinase 2, is a testis-specific form of phosphoglycerate kinase.Originally, it was assumed that PGK2was a pseudogene. However, nowadays it is known that this protein is a functional phosphoglycerate kinase. During the Embden-Meyerhof-Parnas pathway of glycolysis, in thelater stages of spermatogenesis, the protein catalyses the reversible conversion of 1, 3- bisphosphoglycerate to 3-phosphoglycerate.

Inositol Hexakisphosphate Kinase 2 (IP6K2) which is a part of the inositol IPK family converts inositol hexakisphosphate to diphosphoinositol pentakisphosphate. IP6K2 also converts 1, 3, 4, 5, 6-pentakisphosphate (InsP5) to PP-InsP4. IP6K2 is a protein coding gene which suppresses the growth and affects the apoptotic activities of IFN-beta in several ovarian cancers.

AK3L1 is an affiliate of the adenylate kinase family of enzymes. AK3L1 enzyme is restricted to the mitochondrial matrix. Adenylate kinases-3 regulates the adenine and guanine nucleotide compositions within a cell by means of catalyzing the reversible transfer of phosphate group among these nucleotides. 5 different isozymes of adenylate kinase have been identified in vertebrates. The enzyme expression of various adenylate kinase isozymes is growth regulated and tissue-specific.

AKT Serine/Threonine Kinase 3 (Akt3) is a member of the Akt subfamily of serine/threonine protein kinases. Akt3is 1/3 closely related serine/threonine-protein kinases (Akt1, Akt2 and Akt3) called the Akt kinase and which regulate various processes including proliferation, metabolism, cell survival, growth and angiogenesis. The mentioned above is mediated through serine and/or threonine phosphorylation of a range of downstream substrates. Akt3 takes part in brain development and is critical for the viability of malignant glioma cells.

Hexokinases phosphorylate glucose to produce glucose-6-phosphate, thus committing glucose to the glycolytic pathway. HK3 encodes hexokinase 3. Similar to hexokinases 1 and 2, this allosteric enzyme is inhibited by its product glucose-6-phosphate. Hexokinase3 lacks the hydrophobic N-terminal sequence critical for targeting to mitochondria. Hexpkinase3 may have anabolic functions, providing H6P for glycogen or lipid synthesis.

PTP4A2 is part of a small class of the protein tyrosine phosphatase (PTP) family. PTP4A2 is localized to the early endosome that take part in a variety of cellular activities. PTP4A2 protein interacts with the beta-subunit of Rab geranylgeranyltransferase II (beta GGT II), therefore has a role as a regulator of GGT II activity. Overexpression of PTP4A2 in mammalian cells conferred a transformed phenotype, which suggested its role in tumorigenesis.

cAMP-dependent protein kinase type II-alpha regulatory subunit (PRKAR2A) can be phosphorylated by the activated catalytic subunit. PRKAR2A interacts with numerous A-kinase anchoring proteins and regulates the subcellular localization of cAMP-dependent protein kinase.