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SERPINB5 (Maspin) is a tumor suppressor protein of the serine proteinase inhibitor family. Maspin plays a vital role in embryonic development through critical functions in cell adhesion. In addition, Maspin is present in normal breast and prostatic epithelial cells although down regulated in the particular carcinomas. SERPINB5 impedes the growth, invasion, and metastatic properties of mammary tumors as well as the invasive ability of pancreatic ductal adenocarcinoma cells. SERPINB5 being a breast tumor suppressor gene is a significant marker of the disease progression in breast neoplasms. Furthermore, high expression of maspin is linked to squamous cell carcinoma in non-small-cell lung cancer. Moreover, maspin expression has been directly linked with the biological aggressiveness of ovarian carcinoma. Maspin exhibits no serine protease inhibitory activity since it does not undergo the stressed to relaxed conformational transition typical of active serpins.

Serpin Peptidase Inhibitor, Clade B Member 8 (SERPINB8) belongs to the ov-serpin subfamily, which, compared with the archetypal serpin PI1, is characterized by a high degree of homology to chicken ovalbumin, absence of N- and C-terminal extensions, lack of a signal peptide, and a serine instead of an asparagine residue at the penultimate position. The superfamily of high molecular weight serine proteinase inhibitors (serpins) control various intracellular and extracellular processes such as complement activation, fibrinolysis, coagulation, cellular differentiation, tumor suppression, apoptosis, and cell migration.

NCS1 is part of the neuronal calcium sensor gene family, which encode calcium-binding proteins expressed primarily in neurons. NCS1 regulates G protein-coupled receptor phosphorylation in a calcium-dependent manner and can substitute for calmodulin. NCS1 is related with secretory granules and modulates synaptic transmission and synaptic plasticity. NCS1 regulates GRK1 and substitutes for calmodulin. NCS1 stimulates PI4KB kinase activity and participates in long-term synaptic plasticity through its interaction with PICK1. NCS1 takes part in neuron differentiation through inhibition of the activity of N-type voltage-gated calcium channel.

Canopy 3 homolog (CNPY3) is a 271 a.aToll-like receptor specific co-chaperone for HSP90B1. CNPY3 is necessitated for proper TLR folding, excluding that of TLR3, and so controls TLR exit from the endoplasmic reticulum. Therefore, CNPY3i s required for both innate and adaptive immune responses.

Calretinin is an intracellular calcium-binding protein belonging to the troponin C superfamily characterized by a structural motif described as the EF-hand domain. The immunohistochemical detection of calretinin in developing cerebellum is restricted to the later stages indicated by weak staining from week 21 of gestation, in Purkinje and basket cells and in neurons of the dentate nucleus. The intensity of staining increases as the cerebellum matures. In tumors, calretinin has been detected in mesotheliomas and some pulmonary adenocarcinomas.

Aprotinin inhibits the activity of several proteolytic enzymes such as chymotrypsin, kallikrein, plasmin and trypsin. Aprotinin is present in blood and in most tissues, with a high concentration in lung. Aprotinin inhibits pro-inflammatory cytokine release and maintains glycoprotein homeostasis. In platelets, aprotinin reduces glycoprotein loss (e.g., GpIb, GpIIb/IIIa), while in granulocytes it prevents the expression of pro-inflammatory adhesive glycoproteins (e.g., CD11b).

Vimentin expression in human malignant glioma cells depends on cellular density, algorithms of drug delivery and chemo/radio treatment. Vimentin and detyrosinated microtubules provide structural support for the extensive microtentacles observed in detached tumor cells and a mechanism to promote successful metastatic spread. Primary colorectal carcinomas display aberrant expression of vimentin, and have activated Notch and TGFbeta signaling pathways. Vimentin is a strong arterial substrate for transglutaminases. Transglutaminase-mediated vimentin dimerization results in a novel unifying pathway by which vasodilatory and remodeling responses may be regulated. Ablation of vimentin expression inhibits migration and invasion of colon and breast cancer cell lines. Vimentin is the main intermediate filament protein in mesenchymal cells and is therefore of value in the differential diagnosis of undifferentiated neoplasms.

Plasma protease C1 inhibitor (SERPING1) is a part of the serpin superfamily of serine protease inhibitors. SERPING1 plays an important role in regulating activation of both the complement and contact systems. SERPING1 is also activating C1 by coupling with the active catalytic site at the light chains of C1r and C1s. SERPING1 insufficiency results in hereditary angioedema, which is characterized by recurrent episodes of localized angioedema of the skin, gastrointestinal mucosa or upper respiratory mucosa.

Matrix metalloproteinase-7 (MMP-7) also known as matrilysin and PUMP (EC 3.4.24.23) cleaves a number of substrates including collagen types IV and X, elastin, fibronectin, gelatin, laminin and proteoglycans. MMP-7 is closely related to the stromelysin family members but is encoded by a different gene. MMP-7 is the smallest of all the MMPs consisting of a pro-peptide domain and a catalytic domain. It lacks the hemopexin-like domain common to other members of the MMPs. MMP-7 is secreted as a 28 kDa proenzyme and can be activated in vitro by organomercurials and trypsin and in vivo by MMP-3 to a 18 kDa active MMP-7 enzyme. Once activated, MMP-7 can activate pro-MMP-1 and pro-MMP-9 but not pro-MMP-2. MMP-7 is widely expressed having been reported in elevated levels in cycling endometrium as well as in colorectal cancers and adenomas, hepatocellular carcinomas, rectal carcinomas, and approximately 50% of gliomas.

LGALS8 is a prostate-specific antigen that is solely overexpressed in malignant tumors and thus is a supplementary specific identifier of malignancies. LGALS8 is part of the galectin gene family which facilitates both cell-cell and cell matrix interactions in a method parallel to the selectin subgroup of C-type lectins.

CA, also known as carbonic anhydrase is an enzyme. Its main function revolves around the CO2 + H2O HCO3- + H+ (conversion of carbon dioxide to bicarbonate & protons). CA has a zinc ion in its active site. The main function of CA is to keep acid-base balance in the blood stream and various tissues. This enzyme also assists Carbonic Anhydrase I to move CO2 to and from tissues.

Grancalcin is calcium-binding protein which is particularly abundant in human neutrophils. GCA is a member of the penta EF-hand (PEF) subfamily of EF-hand proteins, who also comprises calpain, sorcin, peflin, and ALG-2. GCA undergoes essential conformational changes upon binding of calcium, which subsequently exposes hydrophobic amino acid residues, that direct the protein to hydrophobic surfaces. GCA cooperates with L-plastin, a protein known to have actin bundling activity, which suggests that GCA has a part in the regulation of neutrophils adhesion.

Cathepsin D is synthesized as a 54kDa precursor, which is proteolytically processed to an intermediate 48kDa single chain, which matures into more stable 34kDa and 14kDa two chain form. It is an estrogen-regulated lysosomal protease that has been suggested to facilitate cancer cell migration and invasion by digesting the basement membrane, extracellular matrix, and xonnective tissue. Because of its mitogenic and proteolytic activities, it has been implicated as a prognostic marker in many tumor types. Cathepsin D is expressed in epithelial cells as well as in macrophages.

Capping Protein (Actin Filament) Muscle Z-Line, Alpha 2 also known as CAPZA2 belongs the F-actin capping protein alpha subunit family. It is the alpha subunit of the barbed-end actin binding protein Cap Z. By capping the barbed end of actin filaments, Cap Z regulates the growth of the actin filaments at the barbed end. Among the diseases associated with CAPZA2 are endocarditis, and cervicitis.

Kallikrein-15 (KLK15) is one of the 15 kallikrein subfamily members located in a cluster on chromosome 19. KLK15 contains numerous polyadenylation sites and alternative splicing results in multiple transcript variants encoding different isoforms. KLK15 is over expressed in prostate cancer and therefore uses as a diagnostic or prognostic marker for prostate cancer.

Legumain, also known as LGMN is a lysosomal cysteine protease which is found in all mouse tissues, however it was mainly abundant in the kidney as well as placenta. LGMN plays an essential role in the endosomal/lysosomal degradation system as the Legumain deficiency causes the accumulation of pro cathepsins B, H & L, another group of lysosomal cysteine proteases. Furthermore, over expression of LGMN in tumors is important for invasion/metastasis.

MAPT is a neuronal microtubule associated protein localized mostly on axons.
MAPT promotes tubulin polymerisation and stabilizes microtubules, however it also serves to connect certain signalling pathways to the cytoskeleton. MAPT, in its hyperphosphorylated form, is the main part of paired helical filaments (PHF) and neurofibrillary lesions in Alzheimer''s disease (AD) brain.

Matrix metalloproteinases are a family of zinc and calcium-dependent endopeptidases that break down extracellular matrix proteins. The MMP9 is secreted as a 92kDa zymogen. Cleavage of ProMMP-9 results in the active enzyme, having a molecular weight of approximately 82kDa. MMP9 is composed of the following domains: a gelatin-binding domain consisting of three fibronectin type II units, a catalytic domain containing the zinc-binding site, a proline-rich type V collagen-homologous domain and a hemopexin-like domain. MMP9 is produced by the several cell types: monocytes, macrophages, neutrophils, keratinocytes, fibroblasts, osteoclasts and endothelial cells. MMP9 is involved in inflammatory responses, tissue remodeling, wound healing, tumor growth and metastasis. MMP9 may also play an important part in local proteolysis of the extracellular matrix and in leukocyte migration, as well as in bone osteoclastic resorption. MMP9 cleaves type IV and type V collagens into large C-terminal three quarter fragments and shorter N-terminal one quarter fragments. MMP9 can also degrade fibronectin but not laminin or Pz-peptide.
MMP9 defects may be a cause of susceptibility to intervertebral disc disease (IDD), also known as lumbar disk herniation (LDH).

RAC1 is a GTPase which belongs to the RAS superfamily of small GTP-binding proteins. Members of this superfamily appear to regulate a diverse array of cellular events, including the control of cell growth, cytoskeletal reorganization, and the activation of protein kinases. RAC-1 regulates the actin cytoskeleton but also other cellular processes. RAC1 have been shown to be involved in the regulation of cell-cell adhesion.

Calcium/Calmodulin Dependent Protein Kinase II Inhibitor 1 (CAMK2N1), which interacts with CAMK2B, is a part of the CAMK2N family. CAMK2N1 is also interacts with CAMK2A in a way which requires CAMK2A activation by Ca2+. CAMK2N1 is potent and specific inhibitor of CaM-kinase II (CAMK2).

L1 Cell Adhesion Molecule (L1CAM) which is a cell adhesion receptor of the immunoglobulin superfamily takes part in nerve cell function. L1CAM is a neural cell adhesion molecule involved in the dynamics of cell adhesion and in the generation of transmembrane signals at tyrosine kinase receptors. L1CAM takes part in cell migration, neurite outgrowth and myelination. Furthermore, L1CAM plays an important role in the dynamics of neuronal structure and function in the mature brain.

Alpha 1-microglobulin (A1M) is a lipocalin superfamily member (kernal lipocalins). A1M is a low molecular weight protein component of plasma. A1M is distributed in plasma and extravascular compartments of all organs. Alpha-1 Microglobulin is found in mammals, birds, amphibians and fish. The primary sites of A1M synthesis are the liver and the kidney. Around the opening of the lipocalin pocket three lysyl residues are situated; those residues carry yellow-brown modification derived from the binding and degradation of heme and kynurenin (a tryptophan metabolite). A1-Microglobulin’s reductase and dehydrogenase have broad biological substrate specificity properties due to its’ free cysteine side-chain which is located in a flexible loop. Alpha-1-microglobulin is glycosylated by three separate carbohydrate chains: two complex carbohydrates which are N-linked to asparagines at residues 17 and 96, and the other simple carbohydrate which is O-linked to threonine at position 5. The carbohydrates comprise 22% of the total molecular mass of the protein. The glycosylation varies between species.
A1M exists in two forms- a free form and complexed to other macromolecules: in humans- complexed to immunoglobulin A (IgA), in rat- complexed to alpha-1-inhibitor-3. Free A1M is exceptionally heterogeneous in charge (therefore also known as protein HC), and is found tightly linked to a chromophore. The free Alpha-1-microglobulin is a monomeric protein composed of one 188 residue polypeptide and contains three cysteines, two of which (residues 75 and 173) form a conserved intra-molecular disulphide link. The chromophoric group is covalently bound to the free cysteine residue at position 34. A1M binds retinol as a major ligand, but this is probably distinct from its covalent chromophore.
Half of all human plasma A1M (approximately 0.03mg/ml) forms a 1:1 complex with about 5% of plasma immunoglobulin A. The resulting macromolecular complexes’ molecular weight is 200000, and a plasma concentration of 0.3mg/ml. The complex can exhibit both antibody activity and affect many of the biological actions of free Alpha-1-microglobulin.
Alpha-1-microglobulin was first discovered in pathological human urine.
It was suggested that A1M might be involved in tissue defense against reactive oxygen species, oxidation by heme and kynurenin. Evidence also suggests that A1M functions in the regulation of the immune system. Other functions include inhibition of stimulation of cultured lymphocytes by protein antigens; induction of cell division of lymphocytes, a mitogenic effect that can either be enhanced or inhibited by the action of other plasma components; inhibition of neutrophil granulocyte migration in vitro; and inhibition of chemotaxis.

Serpin Peptidase Inhibitor, Clade B Member 4, also known as SERPINB4 is a member of the serpin family. SERPINB4 acts as a protease inhibitor to modulate the host immune response against tumor cells. Among the diseases associated with SERPINB4 are: inverted papilloma as well as burns.

S100Z is a recently discovered member of the S100 protein family. S100 proteins are small dimeric members of the EF-hand superfamily of Ca(2+) binding proteins thought to participate in mediating intracellular Ca(2+) signals by binding to and thereby regulating target proteins in a Ca(2+)-dependent manner. S100Z is a 99-amino acid protein capable of interacting with another member of the family, S100P. There are differences in the expression level of S100Z mRNA in various tissues. The highest levels were found in spleen and leukocytes. S100Z gene expression appears to be deregulated in some tumor tissues, compared to expression in their normal counterparts.