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The somatomedins, or insulin-like growth factors (IGFs), comprise a family of peptides that play important roles in mammalian growth and development. IGF1 mediates many of the growth-promoting effects of growth hormone (GH; MIM 139250). Early studies showed that growth hormone did not directly stimulate the incorporation of sulfate into cartilage, but rather acted through a serum factor, termed 'sulfation factor,' which later became known as 'somatomedin' (Daughaday et al., 1972). Three main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2; MIM 147470), and somatomedin B (MIM 193190) (Rotwein, 1986; Rosenfeld, 2003).

Human TNFRSF10A is a type 1 transmembrane protein in the TNF R superfamily. TNFRSF10A is not expressed in rodents. The trimeric ligand Trail binds TNFRSF10A and induces apoptosis, and recombinant, soluble forms of the receptor inhibit Trail-induced apoptosis. TNFRSF10A is expressed generally in damaged, infected, and malignant cells. TNFRSF10A functions in immune surveillance, inducing apoptosis in cancer cells but not normal cells.

EIF3K is a member of the eIF3 subunit K family. EIF3K is the smallest subunit of eIF3 and it interacts with a number of other subunits of eIF3 and the 40S ribosomal subunit. EIF3K is conserved among high eukaryotes, including mammals, insects, and plants, and it is universally expressed in human tissues. EIF3K is distributed both in nucleus and cytoplasm and colocalized with cyclin D3, a regulatory subunit of cyclin-dependent kinase 4 (Cdk4).

TNFSF12 is a cytokine that is part of the TNF ligand family. TNFSF12 is a ligand for the FN14/TWEAKR receptor. TNFSF12 has overlapping signaling functions with TNF, but displays a much wider tissue distribution. TNFSF12 induces apoptosis through multiple pathways of cell death in a cell type-specific manner. TNFSF12 promotes proliferation and migration of endothelial cells, and therefore acts as a regulator of angiogenesis. TNFSF12 is expressed in adult heart, pancreas, skeletal muscle, small intestine, spleen and peripheral blood lymphocytes. TWEAK h induces NFkB and chemokine secretion. TNFSF12 exerts an apoptotic activity in HT-29 human adenocarcinoma cells whilst cultured in the presence of IFN-?. TNFSF12 promotes proliferation and migration of endothelial cells.

Human Factor IX also called Christmas-Factor is a glycoprotein, which is synthesized in the liver and belongs to the serine proteases system and is part of the S1 peptidase family.
Lack of Factor-IX causes Hemophilia-B meaning Christmas Disease. Factor-IX has a N-terminus region which contains 12xGla residues which asist the calcium dpendant binding of Factor-IX to the phospholipid surface. Factor-IX is activated by either factor XIa or the factor VIIa/tissue factor/phospholipid complex. Cleavage yields the intermediate IXa, which is subsequently converted to the fully active form IXab.
Factor-IX binds initially to exosites on the factor XIa heavy chain, followed by interaction at the active site with subsequent bond cleavage. Coagulation factor IX is activated by interaction with the erythrocyte membrane, causing intrinsic coagulation. Chaperones & lectins act simultaniously to guarantee the proper folding of Factor-IX and the retention of mutant molecules. Human Factor IX, activated by either the Contact or Tissue Factor Pathway, is responsible for the activation of Factor X to Xa.

Eukaryotic translation initiation factor 3, subunit I (EIF3I) is part of the eukaryotic translation initiation factor 3 (eIF-3) complex, which is essential for numerous steps in the initiation of protein synthesis. The eIF-3 complex links with the 40S ribosome and facilitates the recruitment of eIF-1, eIF-1A, eIF-2: GTP: methionyl-tRNAi and eIF-5 to form the 43S pre-initiation complex (43S PIC). The eIF-3 complex stimulates mRNA recruitment to the 43S PIC and scanning of the mRNA for AUG recognition. The eIF-3 complex is also essential for disassembly and recycling of post-termination ribosomal complexes and subsequently prevents premature joining of the 40S and 60S ribosomal subunits prior to initiation. Among the diseases associated with EIF3I are clonorchiasis, and tonsillitis.

Transforming Growth Factor Beta Induced protein also known as TGFBI is an extracellular matrix protein induced by transforming growth factor (TGF)-beta 1. TGFBI protein is involved in cell growth, cell differentiation, wound healing and cell adhesion. In addition, some missense mutations of TGFBI were identified in families affected with human autosomal dominant corneal dystrophies. TGFBI gene encodes for a 683 amino-acid protein containing an RGD motif and four internal repeated domains which have highly conserved sequences founded in several species (Fasciclin domain).

IGF-1 (Insulin-like growth factor-1) is a major hormonal mediator of statural growth. Under regular circumstances, GH (growth hormone) binds to its receptor in the liver, and other tissues, and stimulates the synthesis/secretion of IGF-1. In target tissues, the Type 1 IGF receptor, that is homologous to the insulin receptor, is activated by IGF-1, leading to intracellular signaling which stimulates multiple processes leading to statural growth. IGF-1 metabolic actions are partly directed at stimulating the uptake of glucose, fatty acids, and amino acids so that metabolism supports growing tissues.

NCF1 is a cytosolic subunit protein of neutrophil NADPH oxidase which a
Multi-component enzyme that is activates production of superoxide anion. NCF1, along with NCF2 and a membrane bound cytochrome b558, is necessary for activation of the latent NADPH oxidase necessary for superoxide production. Mutations in this NCF1 have been related with chronic granulomatous disease.

WNT1-inducible-signaling pathway protein 2 (WISP2) belongs to the WNT1 inducible signaling pathway (WISP) protein subfamily, which belongs to the connective tissue growth factor (CTGF) family. The CTGF family members are characterized by 4 conserved cysteine-rich domains: insulin-like growth factor-binding domain, von Willebrand factor type C module, thrombospondin domain and C-terminal cystine knot-like (CT) domain. WISP2 protein lacks the CT domain which is implicated in dimerization binding. WISP2 is possibly involved in bone remodeling. WISP2 is expressed in primary osteoblasts and fibroblasts. WISP2 stimulates osteoblast adhesion and inhibits osteocalcin production. WISP2 expression in colon tumors is reduced while the other 2 WISP members are overexpressed in colon tumors. WISP2 may play an imperative role in modulating bone turnover.

Eukaryotic Translation Initiation Factor 3F, also known as EIF3F belongs to the eIF-3 subunit F family. EIF3F is a component of the eukaryotic translation initiation factor 3 (eIF-3) complex, which isessential for several steps in the initiation of protein synthesis. The eIF-3 complex associates with the 40S ribosomeand facilitates the recruitment of eIF-1, eIF-1A, eIF 2: GTP: methionyl-tRNAi and eIF-5 to form the 43S preinitiationcomplex (43S PIC). In addition, the eIF-3 complex stimulates mRNA recruitment to the 43S PIC and scanning of the mRNA forAUG recognition. The eIF-3 complex is also necessary for disassembly and recycling of post termination ribosomalcomplexes and subsequently prevents premature union of the 40S and 60S ribosomal subunits prior to initiation. Among the diseases associated with EIF3F are intrahepatic cholangiocarcinoma, and cholangiocarcinoma.

Inducible T-Cell Costimulator Ligand also known as ICOSLG, is part of the B7 family of co-stimulatory molecules related to B7-1 and B7-2. ICOSLG is a transmembrane glycoprotein with extracellular IgV and IgC domains, in addition it binds to ICOS on activated T cells. The dependent signaling of ICOSLG takes part in a proliferative response.

Leukemia Inhibitory Factor also called LIF is a lymphoid factor that promotes long-term maintenance of embryonic stem cells by suppressing spontaneous differentiation. Leukemia Inhibitory Factor has several functions such as cholinergic neuron differentiation, control of stem cell pluripotency, bone & fat metabolism, mitogenesis of factor dependent cell lines & promotion of megakaryocyte production in vivo. Human and mouse LIF exhibit a 78% identity in its amino acid sequence.

The cytokine Macrophage migration inhibitory factor (MIF) has been identified to be secreted by the pituitary gland and the monocyte/macrophage and to play an important role in endotoxic shock. MIF has the unique property of being released from macrophages and T cells in response to physiological concentrations of glucocorticoids. The secretion of MIF is tightly regulated and decreases at high, anti-inflammatory steroid concentration.

Vascular endothelial growth factor is an important signaling protein involved in both vasculogenesis and angiogenesis. 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 angiogenesis, vasculogenesis and endothelial cell growth, 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.
Elevated levels of this protein is linked to POEMS syndrome, also known as Crow-Fukase syndrome. Mutations in this gene have been associated with proliferative and nonproliferative diabetic retinopathy.

Stromal Cell-Derived Factor 2 (SDF2) is a secretory protein which is partly similar to the hydrophilic segments of yeast mannosyltransferases. SDF2 protein’s expression is ubiquitous and the gene is rather conserved among mammals. SDF2 is a protein-coding gene whose alternative splicing results in coding and non-coding variants.

Hepatocyte Growth Factor (HGF) is a multifunctional growth factor which regulates both cell growth and cell motility. It exerts a strong mitogenic effect on hepatocytes and primary epithelial cells. HGF synergizes with Interleukin-3 and GM-CSF to stimulate colony formation of hematopoietic progenitor cells in vitro and may, therefore, also modulate hematopoiesis. HGF is secreted as a single inactive polypeptide which is cleaved by serine proteases into a 69kDa Alpha chain and 34kDa Beta chain. A disulfide bond linking the alpha and beta chains produces the active heterodimeric molecule.

BAIAP2 is a ubiquitous regulator of the actin cytoskeleton. Controled by the Rho-family GTPases BAIAP2 facilitates filopodia development. BAIAP2 is expressed in the cytoplasm and binds small membrane-bound G-proteins to cytoplasmic effector proteins. BAIAP2 was identified as interacting with the dentatorubral-pallidoluysian atrophy gene, which is related to an autosomal dominant neurodegenerative disease.

Platelet factor-4 is a 70-amino acid protein that is released from the alpha-granules of activated platelets . Its major physiologic role appears to be neutralization of molecules on the endothelial surface of blood vessels, thereby inhibiting local antithrombin III activity and promoting coagulation. As a strong chemoattractant for neutrophils and fibroblasts, PF4 probably has a role in inflammation and wound repair. Oncostatin-A is a member of the CXC chemocinfamily. Human PF4 is used for the proof of induced thrombocytopenia. Furthermore it is used as an inhibitor in the angiogenesis during tumor therapy.

Connective Tissue Growth Factor belongs to the CCN family of proteins. The CCN family presently consists of six members in human also known as: Cyr61 (Cystein rich 61), CTGF (Connective Tissue Growth Factor), Nov (Nephroblastoma Overexpressed gene), WISP-1, 2 and 3 (Wnt-1 Induced Secreted Proteins). The CCN genes encode secreted proteins associated with the Extracellular Matrix (ECM) and cell membrane.
CCN proteins are matricellular proteins which are involved in the regulation of various cellular functions including: proliferation, differentiation, survival, adhesion and migration. They are expressed in derivatives of the three embryonic sheets and are implicated in the development of kidney, nervous system, muscle, bone marrow, cartilage and bone. During adulthood, they are implicated in wound healing, bone fracture repair, and pathologies such as: fibrosis, vascular ailments and tumorigenesis.
Full length secreted CCN proteins can show an antiproliferative activity, whereas truncated isoforms are likely to stimulate proliferation and behave as oncogenes.
The full length protein consists of four modules: Module I shares partial identity with the N-terminal part of the Insulin-like Growth Factor Binding Proteins (IGFBPs).
Module II includes a stretch of 70amino acid residues – which shares sequence identity with the Von Willebrand Factor Type C repeat (VWC).
Module III contains sequences sharing identity with the Thrombospondin type 1 repeat (TSP1) (WSXCSXXCG), which is thought to be implicated in the binding of sulfated glycoconjugates and to be important for cell adhesion.
Module IV, also designated CT, is encoded by exon5. It is the leasts conserved one of the four domains at the level of nucleotide sequence, but it appears to be critical for several of the biological functions attributed to the CCN proteins. Module IV resembles the CT domain of several extracellular protein including, Von Willebrand's factor and mucins. Sequence similarities to heparin-binding motifs are also found within this domain.
Proteolysis of the secreted full-length CCN proteins that has been reported in the case of CCN2 and CCN3 might result in the production of CCN-derived peptides with high affinity for ligands that full-length CNN proteins bind only poorly. Amino-truncated CCN2 isoforms were biologically active whereas no specific biological activity has been attributed to the truncated CCN3. Although the molecular processes underlying the production of these secreted isoforms is presently unknown, it is important to note that proteolysis occur at the same amino acid residues in both CCN2 and CCN3. An elevated expression of CCN2 has also been detected by Northern blotting in human invasive mammary ductal carcinomas, dermatofibromas, pyogenic granuloma, endothelial cells of angiolipomas and angioleiomyomas, and in pancreatic tumors. A study performed with chondrosarcomas representative of various histological grades established that CCN2 expression was closely correlated with increasing levels of malignancy.
In agreement with CCN2 playing a role in brain tumor angiogenesis, immunocytochemistry studies indicated that both glioblastoma tumor cells and proliferating endothelial cells stained positive for CCN2. In astrocytomas, CCN2 expression was particularly elevated in high grade tumors, with a marked effect of CCN2 on cell proliferation. Downregulation of CCN2 expression in these cells was associated with a growth arrest at the G1/S transition while over-expression of CCN2 induced a two-fold increase of the number of cells in the G1 phase. Gene profiling analysis allowed to identify a set of about 50 genes whose expression might account for the proliferative activity of CCN2 in these cells.
CCN2 was seen in a higher proportion of mononuclear cells of patients with acute lymphoblastic leukemia.

TNFR1 belongs to the TNF-receptor superfamily. TNFR1 is a receptor for TNFSF2/TNF-alpha and homotrimeric TNFSF1/lymphotoxin-alpha.
There are 2 types of soluble TNF receptors: sTNFR-I and sTNFR-II, which act to neutralize the biological activities of TNF alpha and TNF beta. The levels of these soluble receptors seem to increase as a result of shedding of the extracellular domains of the membrane bound receptors. TNF-a, TNFR1 and TNFR2 have roles in cellular differentiation. TNFR1 and TNFR2 function in cell type-specific renal injury.
TNFR1 is capable of signaling both cell survival and apoptosis. TNFR1-induced apoptosis requires 2 sequential signaling complexes. TNFR1 is capable of activating NF-kappaB, mediate apoptosis, and function as a regulator of inflammation. Oxidative stress promotes TNFR1 and TNFR2 self-interaction, ligand-independent and enhanced ligand-dependent TNF signaling. TNFR1 contributes to the induction of non-cytocidal TNF effects including anti-viral state and activation of the acid sphingomyelinase. Human TNFR1 has a major region which controls cell surface expression. High levels of soluble TNF receptors are found in the amniotic fluid of pregnant women.
Germline mutations of the extracellular domains of TNFR1 are linked to the autosomal dominant periodic fever syndrome. The impaired receptor clearance is believed to be a mechanism of the disease. Familial hibernian fever (FHF) is caused by defects in TNFRSF1A gene.

GDF10 is a member of the BMP family and the TGF-beta superfamily. GDF10 is expressed in femur, brain, lung, skeletal, muscle, pancreas and testis, and has a role in head formation and possibly multiple roles in skeletal morphogenesis. In humans, GDF10 mRNA is found in the cochlea and lung of fetuses, and in testis, retina, pineal gland, and other neural tissues of adults. The BMP family members are regulators of cell growth and differentiation in both embryonic and adult tissues. These proteins are characterized by a polybasic proteolytic processing site which is cleaved to produce a mature protein containing 7 conserved cysteine residues.

EIF2S1 participates in the premature steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA which binds to a 40S ribosomal subunit, followed by mRNA binding to create a 43S pre-initiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 should exchange with GTP by way of a reaction catalyzed by eIF-2B.

The somatomedins, IGFs, comprise a family of peptides that play important roles in mammalian growth and development. IGF1 mediates many of the growth-promoting effects of GH. Early studies showed that GH did not directly stimulate the incorporation of sulfate into cartilage, but rather acted through a serum factor, termed 'sulfation factor,' which later became known as 'somatomedin. Three main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2; MIM 147470), and somatomedin B.