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Fibroblast Growth Factors (FGFs) comprise a family of at least eighteen structurally realted proteins that are involved in a multitude of physiological and pathological cellular processes, including cell growth, differentation, angiogenesis, wound healing and tumorgenesis. The biological activities of the FGFs are mediated by a family if type I transmembrane tyrosine kinases which undergo dimerization and autophosphorylation after ligand binding. Four distinct genes encoding closely related FGF receptors, FGFR-1to -4 are known. Multiple forms of FGFR-1 to -3 are generated by alternative splicing of the mRNAs. A frequent splicing event involving FGFR-1 and -2 results in receptors containing all three Ig domains, referred to as the alpha isoform, or only IgII and IgIII, referred to as the ? isoform. Only the alpha isoform has been identified for FGFR-3 and FGFR-4. Additional splicing events for FGFR-1 to -3, involving the C-terminal half of the IgIII domain encoded by two mutually exclusive alternative exons, generate FGF receptors with alternative IgIII domains (IIIb and IIIc). A IIIa isoform which is a secreted FGF binding protein containing only the N-terminal half of the IgIII domain plus some intron sequences has also been reported for FGFR-1. Mutations in FGFR-1 to -3 have been found in patients with birth defects involving craniosynostosis.

TGFB2 is a 27.08 kDa protein having two identical 118 amino acid peptide chains linked by a single disulfide bond. TGFB2 is part of a family of five related cytokines that have an extensive variation of normal and neoplastic cells, indicating the importance of these homo-dimmer proteins as multi-functional regulators of cellular activity. The three mammalian isoforms of TGF-β (TGFb1, TGFb2 and TGFb3) signal through the same receptor and stimulate similar biological responses. They are involved in physiological processes as embryogenesis, tissue remodelling and wound healing.

FGF4 holds s comprehensive mitogenic and cell survival activities and takes part in a range of biological processes including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. FGF4 possess oncogenic transforming activity. FGF4 and FGF3, oncogenic growth factors are localized on chromosome 11. Co-amplification of both factors was found in several kinds of human tumors. FGF4 functions in bone morphogenesis and limb development through the sonic hedgehog (SHH) signaling pathway.

RANGRF is a protein which acts as a guanine nucleotide release factor in mouse and regulates the expression and function of the Nav1.5 cardiac sodium channel in human. RANGRF also controls the intracellular trafficking of RAN. In cardiac cells, the RANGRF appears to regulate the cell surface localization of SCN5A.

Interleukin-22 (IL-22), also known as IL-10-related T cell-derived inducible factor (IL-TIF) was initially identified as a gene induced by IL-9 in mouse T cells and mast cells. Mouse IL-22 cDNA encodes a 179 amino acid residue protein with a putative 33 amino acids signal peptide that is cleaved to generate a 147 aa mature protein that shares approximately 79% and 22% aa sequence identity with human IL-22 and IL-10, respectively. IL-22 has been shown to activate STAT-1 and STAT-3 in several hepatoma cell lines and upregulate the production of acute phase proteins. IL-22 is produced by normal mouse T cells upon Con A activation. Mouse IL-22 expression is also induced in various organs upon lipopolysaccharide injection, suggesting that IL-22 may be involved in inflammatory responses. The functional IL-22 receptor complex consists of two receptor subunits, IL-22R (previously an orphan receptor named CRF2-9) and IL-10R? (previously known as CRF2-4), belonging to the class II cytokine receptor family.

The Fas receptor (CD95) mediates apoptotic signaling by Fas-ligand expressed on the surface of other cells. The Fas-FasL interaction plays an important role in the immune system and lack of this system leads to autoimmunity, indicating that Fas-mediated apoptosis removes self-reactive lymphocytes. Fas signaling is also involved in immune surveillance to remove transformed cells and virus infected cells. Binding of FAS to oligimerized FasL on another cell activates apoptotic signaling through a cytoplasmic domain termed the death domain that interacts with signaling adaptors including FAF, FADD and DAX to activate the caspase proteolytic cascade. Caspase-8 and caspase-10 are first activated, to then cleave and activate downstream caspases, and a variety of cellular substrates that lead to cell death. Caspases cleave nuclear lamins, causing the nucleus to break down and lose its normal structure and another caspase substrate is DFF, inducing cleavage and degradation of the genome. Other caspase substrates are involved in cytoskeletal structure, cell cycle regulation and signaling pathways. Activation of JNK kinase, activation of Jun, and production of ceramide may also play roles in Fas-mediated apoptosis. Activation of fas-mediated apoptosis is opposed by I-FLICE and FAP. Viruses and tumors may escape immune surveillance in part through suppression of fas-mediated apoptosis using similar mechanisms.

Transforming Growth Factor-Alpha (TGF-alpha) belongs to the EGF family of cytokines. TGFA soluble form is discharged from the membrane by proteolytic cleavage. Membrane-bound proTGF-alpha is biologically active and has a role in cell-cell adhesion or in the stimulation of adjacent cells. TGFA expression is common in transformed cells. Additionally, TGFA is expressed in normal tissues during embryogenesis and in adult cells/tissues, including the pituitary, keratinocytes, and macrophages.

Tumor necrosis factor receptor superfamily member 21 or TNFRSF21, is a protein that located in the cell membrane from the TNF receptor superfamily. By activating the NF-kappaB pathway, TNFRSF21 promotes cell apoptosis. The degeneration of cells caused by activating caspase 3 and caspase 6, the TNFRSF21 binds to the N-terminal APP in neuronal cell bodies and axons which leads to apoptosis. TNFRSF21 takes part in signaling cascades activated by stimulation of T-cell receptor.

Mitochondrial antiviral signaling protein (MAVS) is vital for innate immune defense against viruses. MAVS is an intermediary protein essential in the virus-triggered IFN-beta signaling pathways. MAVS is involved in activation of transcription factors that regulate expression of IFN-beta and contributes to antiviral immunity.

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.

The epidermal growth factor receptor (EGF R) subfamily of receptor tyrosine kinases comprises four members: EGF R (also known as HER1, ErbB1 or ErbB), ErbB2 (Neu, HER-2), ErbB3 (HER-3), and ErbB4 (HER-4). All family members are type I transmembrane glycoprotein that has an extracellular domain which contains two cysteine-rich domains separated by a spacer region that is involved in ligand-binding, and a cytoplasmic domain which has a membrane-proximal tyrosine kinase domain and a C-terminal tail with multiple tyrosine autophosphorylation sites. The human EGF R gene encodes a 1210 amino acid (aa) residue precursor with a 24 aa putative signal peptide, a 621 aa extracellular domain, a 23 aa transmembrane domain, and a 542 aa cytoplasmic domain. EGF R has been shown to bind a subset of the EGF family ligands, including EGF, amphiregulin, TGF-a , betacellulin, epiregulin, heparin-binding EGF and neuregulin-2 in the absence of a co-receptor. Ligand binding induces EGF R homodimerization as well as heterdimerization with ErbB2, resulting in kinase activation, tyrosine phosphorylation and cell signaling. EGF R can also be recruited to form heterodimers with the ligand-activated ErbB3 or ErbB4. EGF R signaling has been shown to regulate multiple biological functions including cell proliferation, differentiation, motility and apoptosis. In addition, EGF R signaling has also been shown to play a role in carcinogenesis.

Regulated upon Activation, Normal T-cell Expressed, and Secreted or RANTES is an 8 kDa protein classified as a chemotactic cytokine or chemokine. It has recently been renamed CCL5. RANTES is chemotactic for T cells, eosinophils and basophils and plays an active role in recruiting leukocytes into inflammatory sites. With the help of particular cytokines (i.e. IL-2 and IFN-?) that are released by T cells, RANTES also induces the proliferation and activation of certain natural killer (NK) cells to form CHAK (CC-Chemokine-activated killer) cells. It is also a HIV-suppressive factor released from CD8+ T cells. This chemokine has been localized to chromosome 17 in humans.

Excess adiposity is the most important risk in the development of insulin resistance and type 2 diabetes mellitus (T2DM). Adipose tissue produces several proteins (adipocytokines) such as leptin, adiponectin, resistin, tumor necrosis factor-?, and IL-6, that modulate insulin sensitivity and appear to play an important role in the pathogenesis of insulin resistance, diabetes, dyslipidemia, inflammation, and atherosclerosis. However, the mechanisms by which fat tissue induces insulin resistance and the role of adipocytokines in the pathogenesis of T2DM have not been well established. Visfatin, also known as pre-B cell colony-enhancing factor (PBEF), is a cytokine that is highly expressed in visceral fat and was originally isolated as a secreted factor that synergizes with IL-7 and stem cell factors to promote the growth of B cell precursors. Visfatin homologs have been identified in carp, invertebrate mollusks, and bacteria, as well as in vertebrates, including humans and the mouse. It has been postulated to play a role in innate immunity.
Visfatin exerts insulin-mimetic effects that are dose-dependent and quantitatively similar to those of insulin in stimulating muscle and adipocyte glucose transport, and in inhibiting hepatocyte glucose production. Intravenous injection of recombinant visfatin in mice decreased plasma glucose in a dose-dependent fashion. In keeping with its insulin-mimetic effects, visfatin was as effective as insulin in reducing hyperglycemia in insulin-deficient diabetic mice. Visfatin was also found to be bound to and activate insulin receptor, causing receptor phosphorylation and the activation of downstream signaling molecules. However, visfatin and insulin did not compete for binding to the insulin receptor, indicating that the two proteins were recognized by different regions of the receptor. Thus, visfatin might play a role in glucose homeostasis and dysregulation in biosynthesis or signal transduction, and might contribute to the pathogenesis of diabetes.

Cardiotrophin 1 (CT-1) is a 201 amino acid member of the interleukin-6 superfamily. It was identified by its ability to induce hypertrophic response in cardiac myocytes. CT-1 mRNA levels were found both in cardiac myocytes and in cardiac nonmyocytes. CT 1 was also detected in abundance in normal adult human lung and was expressed in both fetal and adult airway smooth muscle cells. CT 1 activates gp130 dependent signaling and stimulates the Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway to transduce hypertrophic and cytoprotective signals in cardiac myocytes.
CT 1 has also a neurotrophic function. CTF1 deficiency causes increased motoneuron cell death in spinal cord and brainstem nuclei of mice during a period between embryonic day 14 and the first postnatal week. Moreover, CT-1 is a hepatocyte survival factor that efficiently reduces hepatocellular damage in animal models of acute liver injury. Cardiotrophin 1 expression is augmented after hypoxic stimulation and it can protect cardiac cells when added either prior to simulated ischaemia or at the time of reoxygenation following simulated ischaemia. Cardiotrophin 1 can induce expression of the protective heat shock proteins (hsps) in cardiac cells.
Cardiotrophin-1 increased ventricular expression of ANP, brain natriuretic peptide (BNP) and angiotensinogen mRNA.
Cardiophin 1 levels were significantly elevated in patients with heart failure, patients with dilatative cardiomyopathy, moderate/severe mitral regurgitation, stable and unstable angina and after acute myocardial infarction.

CDO1 (Cysteine dioxygenase) is a mammalian non-heme iron enzyme that initiates a number of significant metabolic pathways associated with pyruvate and several sulfurate compounds including sulfate, hypotaurine and taurine. CDO1 catalyzes the conversion of L-cysteine to cysteine sulfinic acid (cysteine sulfinate) by incorporation of dioxygen. CDO1 is a vital regulator of cellular cysteine concentrations and has an essential role in maintaining the hepatic concentration of intracellular free cysteine within a proper narrow range. CDO1 is able to alter intracellular cysteine levels and glutathione levels. CDO1 is highly expressed in the liver and placenta. On the other hand CDO1 has a low expression in heart, brain and pancreas. CDO1 can also be detected in hepatoblastoma HepG2 cells.

FAD-linked sulfhydryl oxidase ALR (GFER) is a member of the Erv1/ALR family of proteins, which is found in higher and lower eukaryotes. GFER is a hepatotrophic growth factor and flavin-linked sulfhydryl oxidase expressed in a variety of tissues. Moreover, GFER induces the expression of S-adenosylmethionine decarboxyl-ase and ornithine decarboxylases (ODC), which each have a central role in the synthesis of polyamines. The hepatotrophic factor designated augmenter of liver regeneration (ALR) is assumed to be one of the factors responsible for the exceptional regenerative capacity of mammalian liver. The GFER gene is located on chromosome 16 in the interval containing the locus for polycystic kidney disease (PKD1).

Fibroblast growth factors (FGFs) comprise a family of at least eighteen structurally related proteins that are involved in a multitude of physiological and pathological cellular processes, including cell growth, differentiation, angiogenesis, wound healing and tumorgenesis. The biological activities of the FGFs are mediated by a family of type I transmembrane tyrosine kinases which undergo dimerization and autophosphorylation after ligand binding. Four distinct genes encoding closely related FGF receptors, FGF R1 - 4, are known. All four genes for FGF Rs encode proteins with an N-terminal signal peptide, three immunoglobulin (Ig)-like domains, an acid-box region containing a run of acidic residues between the IgI and IgII domains, a transmembrane domain and the split tyrosine-kinase domain. Multiple forms of FGF R1 - 3 are generated by alternative splicing of the mRNAs. A frequent splicing event involving FGF R1 and 2 results in receptors containing all three Ig domains, referred to as the a isoform, or only IgII and IgIII, referred to as the b isoform. Only the a isoform has been identified for FGF R3 and FGF R4. Additional splicing events for FGF R1 - 3, involving the C-terminal half of the IgIII domain encoded by two mutually exclusive alternative exons, generate FGF receptors with alternative IgIII domains (IIIb and IIIc). A IIIa isoform which is a secreted FGF binding protein containing only the N-terminal half of the IgIII domain plus some intron sequences has also been reported for FGF R1. Mutations in FGF R1 - 3 have been found in patients with birth defects involving craniosynostosis. The complex patterns of expression of these receptors as well as the specificity of their interactions with the various FGF ligand family members are under investigation.

Chemokine (C-C motif) ligand 2 (CCL2) is a small cytokine belonging to the CC chemokine family that is also known as monocyte chemotactic protein-1 (MCP-1). It is found at the site of tooth eruption and bone degradation. In the bone, CCL2 is expressed by mature osteoclasts and osteoblasts and is under the control of nuclear factor ?B (NF?B). CCL2 recruits immune cells, such as monocytes, to sites of tissue injury and infection. This chemokine is produced as a protein precursor containing signal peptide of 23 amino acidsand a mature peptide of 76 amino acids. It is a monomeric polypeptide, with a molecular weight of approximately 13kDa. As with many other CC chemokines, CCL2 is located on chromosome 17 in humans. The cell surface receptors that bind CCL2 are CCR2 and CCR5.

ARF4 belongs to the ARF gene family whose members encode small guanine nucleotide-binding proteins which stimulate the ADP-ribosyltransferase activity of cholera toxin and have a role in vesicular trafficking and as activators of phospholipase D. The ARF proteins include five ARF proteins and eleven ARF-like proteins and constitute one family of the RAS superfamily. They are classified as class I, class II and class III; the ARF4 gene is a class II member. The members of each class share a common gene organization. The ARF4 gene spans approximately 12kb and contains 6 exons and 5 introns. The ARF4 gene is the most divergent member of the human ARFs.

Interleukin-22 (IL-22), also known as IL-10-related T cell-derived inducible factor (IL-TIF) was initially identified as a gene induced by IL-9 in mouse T cells and mast cells. Mouse IL-22 cDNA encodes a 179 amino acid residue protein with a putative 33 amino acids signal peptide that is cleaved to generate a 147 aa mature protein that shares approximately 79% and 22% aa sequence identity with human IL-22 and IL-10, respectively. IL-22 has been shown to activate STAT-1 and STAT-3 in several hepatoma cell lines and upregulate the production of acute phase proteins. IL-22 is produced by normal mouse T cells upon Con A activation. Mouse IL-22 expression is also induced in various organs upon lipopolysaccharide injection, suggesting that IL-22 may be involved in inflammatory responses. The functional IL-22 receptor complex consists of two receptor subunits, IL-22R (previously an orphan receptor named CRF2-9) and IL-10Rβ (previously known as CRF2-4), belonging to the class II cytokine recep

Tumor necrosis factor is a cytokine involved in systemic inflammation and is a member of a group of cytokines that all stimulate the acute phase reaction. TNF is mainly secreted by macrophages.
TNF causes apoptotic cell death, cellular proliferation, differentiation, inflammation, tumorigenesisand viral replication, TNF is also involved in lipid metabolism, and coagulation. TNF's primary role is in the regulation of immune cells.
Dysregulation and, in particular, overproduction of TNF have been implicated in a variety of human diseases- autoimmune diseases, insulin resistance, and cancer.

Oncostatin M is a member of a cytokine family that includes leukemia-inhibitory factor, granulocyte colony-stimulating factor, and interleukin 6. This gene encodes a growth regulator which inhibits the proliferation of a number of tumor cell lines. It regulates cytokine production, including IL-6, G-CSF and GM-CSF from endothelial cells.

Vascular endothelial growth factor (VEGF) is an important signaling protein involved in vessel formation As its name implies, VEGF activity has been mostly studied on cells of the vascular endothelium, although it does have effects on a number of other cell types (e.g. stimulation monocyte/macrophage migration, neurons, cancer cells, kidney epithelial cells ). VEGF mediates increased vascular permeability, induces vasculogenesis and endothelial cell production, promotes cell migration, and inhibits apoptosis. In vitro, VEGF has been shown to stimulate endothelial cell mitogenesis and cell migration. VEGF is also a vasodilator and increases microvascular permeability and was originally referred to as vascular permeability factor. VEGF is located in normal cartilage though only osteoarthritic cartilage expresses the VEGF receptors, NP1, VEGFR1 and VEGFR2. The VEGF level in the culture media from OA chondrocytes was more than 3 folds higher than in media from normal chondrocytes