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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.

Galectin-4 is a member of the subfamily of galectins composed of two carbohydrate recognition domains having similar peptide chains. The galectins are a family of beta-galactoside-binding proteins having a role in modulating cell-cell and cell-matrix interactions, which inhibits chronic inflammations, GVHD, and allergic responses. LGALS4 expression is limited to small intestine, colon, and rectum, and it is underexpressed in colorectal cancer. LGALS4 binds as an endogenous ligand to glycosphingolipids having 3-O-sulfated Gal residues and bind as well to cholesterol-3-sulfate. LGALS4 takes part in cell adhesion. LGALS4 plays a role in crosslinking the lateral cell membranes of the surface-lining epithelial cells, thus supporting epithelial integrity against mechanical stress exerted by the bowel lume. LGALS4 is in charge of intestinal inflammation via selective regulation of peripheral and mucosal T-cell cell cycle, in addition to cell death by apoptosis of T-cells by a pathway independent of the activation of caspases. LGALS4 blockade decreases TNF-alpha inhibitor induced T-cell death. LGALS4 decreases pro-inflammatory cytokine secretion including IL-6 & IL-17.

Myosin Binding Protein C, Cardiac (MYBPC3) is the cardiac isoform of myosin-binding protein C expressed exclusively in heart muscle. Myosin-binding protein C is a myosin-associated protein found in the cross-bridge-bearing zone (C region) of A bands in striated muscle. Regulatory phosphorylation of the cardiac isoform in vivo by cAMP-dependent protein kinase upon adrenergic stimulation may be associated with modulation of cardiac contraction. MYBPC3 gene mutations are one of the causes of familial hypertrophic cardiomyopathy. In vitro MYBPC3 binds MHC, F-actin and native thin filaments, and modifies the activity of actin-activated myosin ATPase. MYBPC3 may modulate muscle contraction or it may have a more structural role.

Sclerostin (SOST) is a secreted glycoprotein with a C-terminal cysteine knot-like (CTCK) domain and sequence similarity to the DAN (differential screening-selected gene aberrative in neuroblastoma) family of bone morphogenetic protein antagonists. Sclerostin functions as a negative regulator of bone growth, by inhibiting bone formation. SOST is expressed mainly in the bone, cartilage, kidney, liver, bone marrow and primary osteoblasts differentiated for 21 days. SOST gene defects cause sclerosteosis and bone dysplasia.

TNNI2 is a fast-twitch skeletal muscle protein, belongs to the troponin I gene family, and is part of the troponin complex including troponin T, troponin C and troponin I subunits. The troponin complex, together with tropomyosin, is responsible for the calcium-dependent regulation of striated muscle contraction. TNNI2 is also present in vascular smooth muscle and may play a role in regulation of smooth muscle function. Other than muscle tissues, TNNI2 is found in corneal epithelium, cartilage where it is an inhibitor of angiogenesis to inhibit tumor growth and metastasis, and mammary gland where it functions as a coactivator of estrogen receptor-related receptor alpha. Furthermore, TNNI2 suppresses tumor growth in human ovarian carcinoma. Mutations in the TNNI2 gene cause myopathy and distal arthrogryposis type 2B.

Galectin-3 mediates with the alpha-3, beta-1 integrin the stimulation by cspg4 of endothelial cells migration. Galectin-3 plays an necessary part during the acquisition of vasculogenic mimicry and angiogenic properties associated with melanoma progression. LGALS3 overexpression is highly expressed in early stages of papillary carcinoma, and its expression intensity declines during tumor progression. Serum levels of LGALS3 are high in patients with thyroid malignancy but there is considerable overlap in serum LGALS3 concentrations between those with benign and malignant nodular thyroid disease. LGLAS3 takes part as an immune regulator to inhibit T-cell immune responses and promote tumor growth, as a result providing a new mechanism for tumor immune tolerance.

S100A8 is a part of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a broad range of cells, and participate in the regulation of cellular processes such as cell cycle progression and differentiation. S100A8 plays a role in the inhibition of casein kinase and as a cytokine. S100A8 altered expression is related with cystic fibrosis disease. S100A8 is a calcium-binding protein that has antimicrobial activity against bacteria and fungi.S100A8 is crucial for resistance towards invasion by pathogenic bacteria. S100A8 up-regulates transcription of genes that are under the control of NF-kappa-B. S100A8 plays a role in the development of endotoxic shock in response to bacterial lipopolysaccharide. S100A8 endorses tubulin polymerization and promotes phagocyte migration and infiltration of granulocytes at sites of wounding. S100A8 takes part as a pro-inflammatory mediator in acute and chronic inflammation and up-regulates the release of IL8 and cell-surface expression of ICAM1.

ANXA5 is a member of the annexin family of calcium-dependent phospholipid binding proteins which are involved in membrane-related activity along exocytotic and endocytotic pathways. ANXA5 is a phospholipase A2 and protein kinase C inhibitory protein with calcium channel properties and takes part in cellular signal transduction, inflammation, growth and differentiation. ANXA5 is an anticoagulant protein that acts as an indirect inhibitor of the thromboplastin-specific complex, which is involved in the blood coagulation cascade. ANXA5 regulates coagulability in the blood stream by binding to phosphatidylserine and sulfatide. ANXA5 protects sinsuoidal endothelial cells from ischemia reperfusion damage. ANXA5 is necessary for normal CFTR chloride channel activity.

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.

CASQ2 belongs to the calsequestrin family and is localized to the sarcoplasmic reticulum in cardiac and slow skeletal muscle cells. CASQ2 is a calcium binding protein that stores calcium for muscle function. The discharge of calcium bound to CASQ2 through a calcium release channel activates muscle contraction. CASQ2 binds 40 to 50 moles of calcium. CASQ2 mutations result in stress-induced polymorphic ventricular tachycardia, also called catecholaminergic polymorphic ventricular tachycardia 2 which is known fir its bidirectional ventricular tachycardia that causes cardiac arrest.

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.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is widely used in molecular biology through its unique high affinity for the vitamin biotin. The dissociation constant (Kd) of the biotin-streptavidin complex is about ~10-15 mol/L. The strong affinity recognition of biotin and biotinylated molecules has made streptavidin one of the most important components in diagnostics and laboratory kits. The streptavidin/biotin system has one of the biggest free energies of association of yet observed for noncovalent binding of a protein and small ligand in aqueous solution (K_assoc = 10**14). The complexes are also extremely stable over a wide range of temperature and pH.

Procalcitonin is a peptide hormone mainly produced by the C cells of the thyroid and certain endocrine cells of the lung. Under normal expression conditions, procalcitonin is immediately cleaved into three specific fragments, an N terminal residue, calcitonin and katacalcin. Levels of unprocessed procalcitonin rise significantly after bacterial infection, trauma or shock.

Collagen, a major component of the extracellular matrix, is a fibrous protein that provides tensile strength to tissues giving them structural integrity. Collagen and its derivative, gelatin, have been widely used in medical, pharmaceutical and consumer products for more than 100 years. The supply of these materials, created from animal remains, is both abundant and inexpensive. However, most formulations are not highly purified and have the potential to cause an inflammatory reaction in some product users. In addition, concerns have been raised over the last several years about the potential for contamination of bovine products with the agent that causes mad cow disease and its human variant, Creutzfeldt-Jakob Disease. Animal collagens are subject to extensive modifications that continue over the life of the molecule in the extracellular space. These differences influence both the extractability of collagens from tissue and the biophysical characteristics of these collagens. As a result, collagens isolated from tissues exhibit significant lot-to-lot variability and, as bulk materials, are often analytically intractable. Products that contain animal-derived collagen can induce potentially harmful inflammatory or immune responses in humans and pose risk of contamination with viruses or prions, potentially life-threatening pathogens. Recombinant collagens are essentially identical to the native collagen protein thereby reducing the risk of inflammation, immune response, and disease as compared to animal-sourced collagen.

Troponin Complex is a heteromeric protein playing an important role in the regulation of skeletal and cardiac muscle contraction. It consists of three subunits, Troponin I, Troponin T and TroponinC. Each subunit is responsible for part of Troponin Complex function. E.g. Troponin I inhibits ATP-ase activity of acto-myosin.Troponin T and Troponin Iare presented in cardiac muscles in different forms than in skeletal muscles. Purified subunits of rcTnI, rcTnC and rcTnT are recomplexed in vitro under appropriate conditions.

S100b is a member of the S100 family of proteins which are a family of EF-hand calcium binding proteins that exist mostly as dimers of the 20 currently identified individual S100 monomers. The S100B homodimer is expressed in cells of the central nervous system, glial cells and in certain peripheral cells e.g. Schwann cells, melanocytes, adipocytes and chondrocytes. S100 proteins are localized either in the cytoplasm or the nucleus of a wide range of cells. S100 proteins are involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. There are at least 13 members in the S100 gene family, which are located as a cluster on chromosome 1q21; however, S100b is located at 21q22.3. The determination of S100B in serum levels may be used to monitor the extent of brain injury and malignant melanoma. S100b proteins may have a role in Neurite extension, proliferation of melanoma cells, stimulation of Ca2+ fluxes, inhibition of PKC-mediated phosphorylation, astrocytosis and axonal proliferation, and inhibition of microtubule assembly. Chromosomal rearrangements and altered expression of the S100b gene are implicated in several neurological, neoplastic, and other types of diseases, including Alzheimer's disease, Down's syndrome, epilepsy, amyotrophic lateral sclerosis, melanoma, and type I diabetes.

CTNNBIP1 binds CTNNB1 and avoids interaction between CTNNB1 and TCF (T-cell transcription factor) family members. CTNNBIP1 is a negative regulator of the Wnt signaling pathway.

Eosinophil lysophospholipase (CLC) acts on biological membranes to regulate the multifunctional lysophospholipids. CLC is a lysophospholipase expressed in eosinophils and basophils. CLC hydrolyzes lysophosphatidylcholine to glycerophosphocholine and a free fatty acid. The CLC protein may possess carbohydrate or IgE-binding activities. CLC is both structurally and functionally related to the galectin family of beta-galactoside binding proteins. CLC may be linked with inflammation and some myeloid leukemias.

Galectins are a family of animal lectins with an affinity for beta-galactosides. This family has at least 14 identified members. Galectins share similarities in the CRD (the carbohydrate recognition domain). Galectins are synthesized as cytosolic proteins. Though localized principally in the cytoplasm and lacking a classical signal peptide, galectins can also be stimulated to secretion by non-classical pathways or alternatively targeted to the nucleus. Galectins are involved in modulating cell-cell and cell-matrix interactions. Human Galectin-7 belongs to the prototypical Galectins containing a single CRD, which is initially identified in human epidermis as a monomer. The Galectin-7 expression is induced by tumor suppressor protein p53 and associated with apoptosis. Galectin-7 is a pro-apoptotic protein which functions intracellularlly upstream of JNK activation and mitochondrial cytochrome c release. The correlation of Galectin-7 with the UV-induced apoptosis of keratinocytes presents a critical mechanism in the maintenance of epidermal homeostasis. Human Galectin-7 is localized in both nucleus and cytoplasm.

RCAN1 encoded by a gene located in the human chromosome 21, interacts with calcineurin A and inhibits calcineurin-dependent signaling pathways, possibly affecting central nervous system development. RCAN1 is located in the minimal candidate region for the Down syndrome phenotype, and is over expressed in the brain of Down syndrome fetuses. Chronic over expression of this gene may lead to neurofibrillary tangles such as those associated with Alzheimer disease. Three transcript variants encoding three different isoforms have been found for this gene.
DSCR1 Inhibits calcineurin-dependent transcriptional responses by binding to the catalytic domain of calcineurin A, possibly affecting central nervous system development.

Caltractin (CETN2) is a member of a family of calcium-binding proteins and is a structural component of the centrosome. CETN2 has a role in nucleotide excision repair via association with xeroderma pigmentosum group C protein, suggesting possible coupling of cell division and nucleotide excision repair.