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OAS1 enzyme is a member of the 2’,5’-oligoadenylate synthetase family. OAS1 is induced by interferons and uses adenosine triphosphate in 2’-specific nucleotidyl transfer reactions to synthesize 2’,5’-oligoadenylates(2-5As). These molecules in turn activate latent RNase L resulting in viral RNA degradation and the inhibition of viral replication.
OAS1 may have a role in mediating resistance to virus infection, control of cell growth, differentiation, and apoptosis. OAS1 binds double-stranded RNA and polymerizes ATP into PPP (A2'P5'A)N oligomers, which activate the latent RNase L that, once activated, cleaves single-stranded RNAs.
OAS1 gene mutations are been linked to host susceptibility to viral infection.
OSA1 gene polymorphisms are linked to the outcome of hepatitis C virus infection. Furthermore, OAS1 gene polymorphisms are linked to the susceptibility to severe acute respiratory syndrome.

ENO1 is a homodimeric soluble protein that encodes a smaller monomeric structural lens protein, tau-crystallin. ENO1 is a glycolytic enzyme expressed in mainly all tissues. ENO1 isoenzyme full length protein is found in the cytoplasm. The shorter protein is formed from another translation start that is restricted to the nucleus, and binds to a component in the c-myc promoter. ENO1 is involved in anaerobic metabolism under hypoxic conditions and plays a role as a cell surface plasminogen receptor during tissue invasion. Irregular expression of Enolase-1 is linked with tumor progression in several cases of breast and lung cancer. Enolase-1 is as an auto antigen associated with Hashimoto's encephalopathy and severe asthma. ENO1 is the target protein of serum anti-endothelial antibody in Behcet's disease.

TCL1A (T-cell leukemia/lymphoma 1A) is a protein with a possible role in intracellular regulation of T cell signaling. TCL1A enhances cell proliferation, stabilizes mitochondrial membrane potential and promotes cell survival. TCL1A is restricted in the T-cell lineage to immature thymocytes and activated peripheral lymphocytes. TCL1A is preferentially expressed early in T and B-lymphocyte differentiation. Chromosomal anomalies activating TCL1A are found in chronic T-cell leukemias (T-CLL).
TCL1A enhances the phosphorylation and activation of AKT1, AKT2 and AKT3. TCL1A promotes nuclear translocation of AKT1. TCL1A binds to the pleckstrin homology domain of Akt (protein kinase B) family proteins, which facilitates Akt dimerization and activity. By increasing Akt activity, TCL1A can enhance the serine/threonine phosphorylation of major Akt signaling substrates, for example Ikk complex, mTOR, BAD, p70S6 kinase, FOXO transcription factors and GSK3b. These substrates regulate cellular differentiation, growth, survival, and metabolism.

ICAM-1 also called CD54 is a single chain membrane glycoprotein expressed on the surface of a variety of non-haematopoietic and haematopoietic cell types and has roles in signal transduction, cell signaling and lymphocyte adhesion. ICAM1 binds to integrins such as CD11a / CD18, or CD11b / CD18. ICAM1 is also used by Rhinovirus as a receptor. ICAM-1 is an intercellular adhesion molecule constantly present in low concentrations in the membranes of leukocytes and endothelial cells. When stimulated by cytokine the concentrations significantly increase. ICAM-1 can be stimulated by interleukin-1 (IL-1) and tumor necrosis factor alpha (TNFA) and is expressed by the vascular endothelium, macrophages and lymphocytes. ICAM-1 is a ligand for LFA-1 which is a receptor found on leukocytes. Upon activation, leukocytes bind to endothelial cells via ICAM-1/LFA-1 and then transmigrate into tissues. ICAM-1 is implicated in subarachnoid hemorrhage (SAH). Levels of ICAM-1 are shown to be notably elevated in patients with SAH. Soluble ICAM-1 is detectable in the plasma and is elevated in patients with various inflammatory conditions.

SDF-1 (stromal cell-derived factor-1) is small cytokine belonging to the chemokine family that is officially designated Chemokine (C-X-C motif) ligand 12 (CXCL12). It is produced in two forms, SDF-1?/CXCL12a and SDF-1?/CXCL12b, by alternate splicing of the same gene. Chemokines are characterized by the presence of four conserved cysteines, which form two disulfide bonds. The CXCL12 proteins belong to the group of CXC chemokines, whose initial pair of cysteines are separated by one intervening amino acid. CXCL12 is strongly chemotactic for lymphocytes and has been implicated as an important cell co-ordinator during development. During embryogenesis it directs the migration of hematopoietic cells from foetal liver to bone marrow. Mice which were knocked-out for CXCL12 gene were lethal before the birth or within just 1 hour of life. As another role, CXCL12a alters also the electrophysiology of neurons. CXCL12 was shown to be expressend in many tissues in mice (including brain, thymus, heart, lung, liver, kidney, spleen and bone marrow).
The receptor for this chemokine is CXCR4, which was previously called fusin. This CXCL12-CXCR4 interaction used to be considered exclusive (unlike for other chemokines and their receptors), but recently it was suggested that CXCL12 is also bound by CXCR7 receptor.
The gene for CXCL12 is located on human chromosome 10. In human and mouse both CXCL12 and CXCR4 show high identity of sequence: 99% and 90%, respectively.

Lipase Endothelial (LIPG) has extensive phospholipase activity and may be involved in lipoprotein metabolism and vascular biology. The LIPG protein is considered a member of the TG lipase family through its sequence and characteristic lid region which provides substrate specificity for enzymes of the TG lipase family. In addition, the LIPG has triglyceride lipase activities. LIPG hydrolyzes HDLs more efficiently than other lipoproteins. LIPG also binds heparin.

ECHS1 is part of the hydratase/isomerase superfamily. ECHS1 is localized in the mitochondrial matrix and Expressed in muscle, liver and fibroblasts, with low expression in kidney and spleen, ECHS1 exists as a homohexamer that takes part in the second phase of the mitochondrial fatty acid β-oxidation pathway.

ENO1 is a homodimeric soluble protein that encodes a smaller monomeric structural lens protein, tau-crystallin. ENO1 is a glycolytic enzyme expressed in mainly all tissues. ENO1 isoenzyme full length protein is found in the cytoplasm. The shorter protein is formed from another translation start that is restricted to the nucleus, and binds to a component in the c-myc promoter. ENO1 is involved in anaerobic metabolism under hypoxic conditions and plays a role as a cell surface plasminogen receptor during tissue invasion. Irregular expression of Enolase-1 is linked with tumor progression in several cases of breast and lung cancer. Enolase-1 is as an auto antigen associated with Hashimoto's encephalopathy and severe asthma. ENO1 is the target protein of serum anti-endothelial antibody in Behcet's disease.

KISS1 is a metastasis suppressor protein that suppresses metastases of melanomas and breast carcinomas without affecting tumorigenicity.KISS1 functions to inhibit chemotaxis and invasion, attenuating metastasis in malignant melanomas. KISS1 is involved in the regulation of cell-matrix adhesion. KISS1 plays a role in cytoskeletal reorganization. A polymorphism in the terminal exon of KISS1 mRNA results in two protein isoforms. Expression of KiSS1 is localized to specific regions of the hypothalamus in numerous species and is regulated by gonadal steroids and across the estrous cycle..KISS1 generates a c-terminally amidated peptide, metastin which functions as the endogenous ligand of the g-protein coupled receptor gpr54. Activation of the receptor inhibits cell proliferation and cell migration, key characteristics of tumor metastasis.

PTB domain-containing engulfment adapter protein 1 (GULP1) is an evolutionarily conserved adaptor protein essential for efficient phagocytosis of apoptotic cells by phagocytes. Furthermore, GULP1 helps modulate cellular glycosphingolipid and cholesterol transport. In addition, GULP1 may have a role in the internalization and endosomal trafficking of various LRP1 ligands, such as PSAP. Increased cytoplasmic levels of GULP1 are linked with increases in cellular levels of GTP-bound ARF6.

Mediator of ErbB2-driven cell motility 1 (MEMO1) is a member of the UPF0103 family. MEMO1 regulates cell migration by transmitting extracellular chemotactic signals to the microtubule cytoskeleton. Furthermore, MEMO1 controls the localization of APC and CLASP2 to the cell membrane, using the regulation of GSK3B activity. MEMO1 is essential for breast carcinoma cell migration, suggesting a key role in tumorigenesis. MEMO1 is also a mediator of ERBB2 signaling.

EFNA1 belongs to the ephrin (EPH) family. The EPH subfamily is the biggest group of receptor protein kinases and they take part in vital nervous system function and development.

DIRAS1 is a member of a distinct branch of the functionally diverse Ras superfamily of monomeric GTPases. DIRAS1 demonstrates low GTPase activity and exists mainly in the GTP-bound form. Ras proteins operate as binary molecular switches that control intracellular signaling networks. Ras-regulated signal pathways regulate such processes as actin cytoskeletal integrity, proliferation, differentiation, cell adhesion, apoptosis, and cell migration. Ras and ras-related proteins are frequently deregulated in cancers, leading to increased invasion and metastasis, and decreased apoptosis.

HIF1A has a role as a master transcriptional monitor of the adaptive response to hypoxia. Under hypoxic conditions HIF1A activates the transcription of over 40 genes, including, erythropoietin, glucose transporters, glycolytic enzymes, vascular endothelial growth factor, and genes whose protein products increase oxygen release or facilitate metabolic adaptation to hypoxia. HIF1A functions as an essential role in embryonic vascularization, tumor angiogenesis and pathophysiology of ischemic disease.

CD138 takes a part in cell adhesion. CD138 is expressed on the surface of pre-B cells and plasma cells but is absent from mature B cells. SDC1 is a selective marker for B cell lymphoblastic leukemia and lymphoplasmacytoid leukemia. SDC1 is missing from the apoptotic myeloma cells; therefore is a valuable marker for plasma cell and myeloma cells.

EPCAM is a carcinoma-associated antigen and belongs to a family which includes at least 2 type I membrane proteins. The EPCAM protein has a role in embryonic stem cells proliferation and differentiation. EPCAM is used as a target for immunotherapy treatment of human carcinomas. EPCAM is expressed on most normal epithelial cells and gastrointestinal carcinomas and acts as a homotypic calcium-independent cell adhesion molecule. Epithelial cell adhesion molecules (EPCAM) can act as a physical homophilic interaction molecule between intestinal epithelial cells (IECs) and intraepithelial lymphocytes (IELs) at the mucosal epithelium for supplying immunological barrier as a first line of defense against mucosal infection. EPCAM gene mutations result in congenital tufting enteropathy.

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, dendritic cells and on trophoblast cells. The flt-1 gene was first described in 1990. The receptor contains seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular splited tyrosine kinase domain. Compared to VEGFR-2 the Flt-1 receptor has a higher affinity for VEGF but a weaker signaling activity. VEGFR-1 thus leads not to proliferation of endothelial cells, but mediates signals for differentiation. Interestingly a naturally occuring soluble variant of VEGFR-1 (sVEGFR-1) was found in HUVE supernatants in 1996, which is generated by alternative splicing of the flt-1 mRNA. The biological functions of sVEGFR-1 still are not clear, but it seems to be an endogenous regulator of angiogenesis, binding VEGF with the same affinity as the full-length receptor.

MMP-1 (interstitial collagenase) can break down a wide range of substrates including types I, II, III, VII, VIII, and X collagens as well as L-Selectin, pro-TNF, IGFBP-3, IGFBP-5, casein, gelatin, myelin basic protein, pro-MMP2 and pro-MMP9. A significant function of MMP-1 is the degradation of fibrillar collagens in extracellular matrix remodeling. MMP-1 is expressed in fibroblasts, keratinocytes, endothelial cells, monocytes and macrophages. MMP1 can be divided into a number of distinct domains: a prodomain which is cleaved on activation, a catalytic domain containing the zinc binding site and a short hinge region with a carboxyl terminal domain. MMP1 is part of a cluster of MMP genes which localize to chromosome 11q22.3.

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

PRDX1 is part of the peroxiredoxin family of antioxidant enzymes, which reduce hydrogen peroxide and alkyl hydroperoxides. PRDX1 is an important protector of red blood cells against reactive oxygen species and in tumor prevention. PRDX1 is antioxidant protective in cells, and contributes to the antiviral activity of CD8(+) T-cells. PRDX1 has a proliferative effect and is involved in cancer development or progression. Peroxiredoxin-1 is plays a role in redox regulation of the cell. Peroxiredoxin decreases peroxides with reducing equivalents provided through the thioredoxin system but not from glutaredoxin. Peroxiredoxin is involved in eliminating peroxides generated during metabolism. Peroxiredoxin participates in the signaling cascades of growth factors and TNF-alpha by regulating the intracellular concentrations of h(2)o(2).

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).

BCA-1 is a CXC chemokine that is highly expressed in thesecondary lymphoid organs, such as follicles of the spleen, lymph nodes, and Peyer's patches. CXCL13 promotes the migration of B lymphocytes (compared to T cells and macrophages), by stimulating calcium influx into, and chemotaxis of, cells expressing Burkitt's lymphoma receptor 1 (BLR1). BCA1 therefore function in the homing of B lymphocytes to follicles. Human BCA-1 shares a 64% amino acid sequence similarity with the mouse protein and 23 - 34% amino acid sequence identity with other known CXC chemokines. Recombinant or chemically synthesized BCA1 is a potent chemoattractant for B lymphocytes but not T lymphocytes, monocytes or neutrophils. BLR1, a G protein-coupled receptor originally isolated from Burkitt’s lymphoma cells, has now been shown to be the specific receptor for BCA1. Among cells of the hematopoietic lineages, the expression of BLR-1, now designated CXCR-5, is restricted to B lymphocytes and a subpopulation of T helper memory cells.

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, dendritic cells and on trophoblast cells. The flt-1 gene was first described in 1990. The receptor contains seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular splited tyrosine kinase domain. Compared to VEGFR-2 the Flt-1 receptor has a higher affinity for VEGF but a weaker signaling activity. VEGFR-1 thus leads not to proliferation of endothelial cells, but mediates signals for differentiation. Interestingly a naturally occuring soluble variant of VEGFR-1 (sVEGFR-1) was found in HUVE supernatants in 1996, which is generated by alternative splicing of the flt-1 mRNA. The biological functions of sVEGFR-1 still are not clear, but it seems to be an endogenous regulator of angiogenesis, binding VEGF with the same affinity as the full-length receptor.

Thymidine Kinase 1 (TK1) is a phosphotransferase (a kinase): 2'-deoxythymidine kinase, ATP-thymidine 5'-phosphotransferase. TK1 is present in 2 forms in mammalian cells, TK1 and TK2. Thymidine kinases hold a main function in the synthesis of DNA and thus in cell division, as they are part of the distinctive reaction chain to introduce deoxythymidine (present in the body fluids as a result of degradation of DNA from food and from dead cells) into the DNA. Thymidine kinase is necessary for the action of many antiviral drugs. Thymidine kinase is used to select hybridoma cell lines in production of monoclonal antibodies.