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A 16-kDa peptide hormone secreted from white adipocytes and implicated in the regulation of food intake and energy balance. Leptin provides the key afferent signal from fat cells in the feedback system that controls body fat stores.

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.

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.

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.

VAMP5 is part of the vesicle-associated membrane protein (VAMP)/synaptobrevin family and the SNARE superfamily. VAMP5 is involved is vesicle trafficking events that are associated with myogenesis.

Alpha crystallins are composed of two gene products ; alpha-A and alpha-B, for acidic and basic, respectively. Alpha crystallins can be induced by heat shock and are members of the small heat shock protein (sHSP also known as the HSP20). They act as molecular chaperones and hold them in in large soluble aggregates. These heterogeneous aggregates consist of 30-40 subunits; the alpha-A and alpha-B subunits have a 3:1 ratio, respectively. Two additional function of a-crystallins are an autokinase activity and participation in the intracellular architecture. Alpha-B is expressed widely in many tissues and organs and occurs in many neurological diseases.

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.

BCDIN3D is a member of the methyltransferase superfamily and contains 1 Bin3-type SAM domain. BCDIN3D acts in the catalysis of the transfer of a methyl group to an acceptor molecule. BCDIN3D is an O-methyltransferase which specifically dimethylates the 5' monophosphate of pre-miRNAs, serving as a negative regulator of miRNA processing. BCDIN3D mediates the methylation of pre-miR-145, as well as other pre-miRNAs.

Platelet-derived growth factor receptor beta (PDGFRB), belongs to the class III subfamily of receptor tyrosine kinases (RTK) which also consist of the receptors for Flt3-ligand, SCF and M-CSF. PDGFRB takes a vital part in blood vessel development by promoting growth, migration as well as recruitment of pericytes and smooth muscle cells to endothelial cells. PDGFRB helps in rearrangement of the actin cytoskeleton in addition the formation of membrane ruffles. PDGFRB phosphorylates, NCK1, PIK3R1, PTPN11, CBL, SHC1, RASA1/GAP and PLCG1.

MRG-binding protein (MRGBP or C20ORF20) is a 204 amino acid protein which is a part of the NuA4 histone acetyltransferase (HAT) complex that functions to acetylate histone H2A and H4. The HAT complex may be essential for the activation of transcriptional programs linked with oncogene and proto-oncogene mediated growth induction, tumor suppressor mediated growth arrest and replicative senescence, apoptosis, and DNA repair. C20ORF20 also has a potential to interact with MORF4L1/MRG15 and MORF4L2/MRGX.

Periostin is a disulfide linked 90 kDa, 811 amino acid protein originally isolated as a osteoblast-specific factor that functions as a cell adhesion molecule for preosteoblasts and is thought to be involved in osteoblast recruitment, attachment and spreading. Additionally, periostin expression has previously been shown to be significantly increased by both transforming growth factor beta-1(TGFbeta1) and bone morphogenetic protein (BMP-2). OSF-2 has a typical signal sequence, followed by a cysteine-rich domain, a fourfold repeated domain and a C-terminal domain. The fourfold repeated domain of OSF-2 shows homology with the insect protein fasciclin
Periostin mRNA is expressed in the developing mouse embryonic and fetal heart, and that it is localized to the endocardial cushions that ultimately divide the primitive heart tube into a four-chambered heart.

Fractalkine soluble form is chemotactic for t-cells and monocytes, but not for neutrophils. Fractalkine membrane-bound form promotes adhesion of those leukocytes to endothelial cells. Fractalkine regulates leukocyte adhesion and migration processes at the endothelium and binds to CX3CR1. Natural Human Fractalkine is produced as a long protein (373-amino acid) with an extended mucin-like stalk and a chemokine domain on top. The mucin-like stalk permits it to bind to the cell surface. Fractalkine gene is located on human chromosome 16 along with some CC chemokines known as CCL17 and CCL22.

TREM2 is a membrane protein that forms a receptor signaling complex with TYROBP. TREM2 may be involved in chronic inflammation by triggering the production of constitutive inflammatory cytokines. Defects in the TREM2 gene are a source of polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy (PLOSL).

Endothelial cell-specific molecule 1 (ESM1) is a proteoglycan secreted by endothelial cells (mostly in the human lung and kidney tissues) and its mRNA expression is regulated by inflammatory cytokines. ESM1 has potent implications in lung endothelial cell-leukocyte interactions. In addition, ESM1 expression is detected in various epithelia and in adipocytes. ESM1 is involved in angiogenesis and it also promotes angiogenic sprouting. ESM1 expression is upregulated by TNF alpha, IL1 beta, or lipopolysaccharide and downregulated by IFN gamma. Genetically engineered cells overexpressing ESM1 induce tumor formation, implying that ESM1 might be involved in the pathophysiology of tumor growth in vivo.

APRIL which is a part of the TNF ligand superfamily (TNFSF13) is a type II transmembrane protein. Normally, APRIL expression is low in tissues, but is elevated in numerous types of tumors and transformed cell lines.

LGALS2 is a soluble beta-galactoside binding lectin that controls cell-to-cell adhesion and cell-to-extracellular matrix interactions and takes part in tumor progression, pre-mRNA splicing and apoptosis. LGALS2 induces apoptosis in activated T cells and binds to the cytokine lymphotoxin-alpha (LTA) with threat of myocardial infarction.

Vaspin (visceral adipose-specific SERPIN) is a newly identified adipokine, which is a member of serine protease inhibitor family. Vaspin is also a unique insulin sensitizing adipocytokine in obesity. A recent publication indicates that induction of human vaspin mRNA expression in adipose tissue is regulated in a fat depot-specific manner and could be associated with parameters of obesity, insulin resistance, and glucose metabolism.

Resistin, a product of the RSTN gene, is a peptide hormone belonging to the class of cysteine-rich secreted proteins which is termed the RELM family, and is also described as ADSF (Adipose Tissue- Specific Secretory Factor) and FIZZ3 (Found in Inflammatory Zone). Human resistin contains 108 amino acids as a prepeptide, and its hydrofobic signal peptide is cleaved before its secretion. Resistin circulates in human blood as a dimeric protein consisting of two 92 amino acid polypeptides, which are disulfide-linked via Cys26.
Resistin may be an important link between obesity and insulin resistance. Mouse resistin, specifically produced and secreted by adipocyte, acts on skeletal muscle myocytes, hepatocytes and adipocytes themselves so that it reduces their sensitivity to insulin. Steppan et al. have suggested that resistin suppresses the ability of insulin to stimulate glucose uptake. They have also suggested that resistin is present at elevated levels in blood of obese mice, and is down regulated by fasting and antidiabetic drugs. Way et al., on the other hand, have found that resistin expression is severly suppressed in obesity and is stimulated by several antidiabetic drugs.
Other studies have shown that mouse resistin increases during the differentiation of adipocytes, but it also seems to inhibit adipogenesis. In contrast, the human adipogenic differentiation is likely to be associated with a down regulation of resistin gene expression.

Regulation Of Nuclear Pre-MRNA Domain Containing 1A (RPRD1A) is upregulated in cells overexpressing cyclin-dependent kinase inhibitor p15(INK4b) and may have a part in cell cycle regulation. RPRD1A interacts with phosphorylated C-terminal heptapeptide repeat domain (CTD) of the largest RNA polymerase II subunit POLR2A, and partakes in dephosphorylation of the CTD. RPRD1A May function as a negative regulator of cyclin-D1 (CCND1) and cyclin-E (CCNE1) in the cell cycle.

APIP catalyzes the dehydration of methylthioribulose-1-phosphate (MTRu-1-P) into 2,3-diketo-5-methylthiopentyl-1-phosphate (DK-MTP-1-P). APIP has an anti-apoptotic function and inhibits muscle ischemic impairment. APIP inhibits the cytochrome c-dependent and APAF1-mediated cell death.

ANKRD1 takes part in endothelial cell activation and performs as a nuclear transcription factor which negatively controls the expression of cardiac genes.

Interleukin-8 (IL-8) is a chemokine produced by macrophages and other cell types such as epithelial cells. It is also synthesized by endothelial cells, which store IL-8 in their storage vesicles, the Weibel-Palade bodies. When first encountering an antigen, the primary cells to encounter it are the macrophages who phagocytose the particle. Upon processing, they release chemokines to signal other immune cells to come in to the site of inflammation. IL-8 is one such chemokine. It serves as a chemical signal that attracts neutrophils at the site of inflammation, and therefore is also known as Neutrophil Chemotactic Factor.