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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.

Twisted gastrulation Protein (TSG) is a secreted, cysteine-rich protein which has a role in dorsal/ventral patterning in Drosophila and Xenopus by regulating BMP signaling. TSG functions as an agonist for BMP signaling by controlling the inhibitory actions of the BMP antagonist, Chordin/Sog, and the cleavage properties of the metalloprotease, xolloid/tolloid. TSG N-terminal domain binds BMP protein directly and displays BMP antagonist activity.

Human T-lymphotropic virus (HTLV) is a human, single-stranded RNA retrovirus that causes T-cell leukemia and T-cell lymphoma. The virus activates a subset of T-helper cellscalled Th1cells. The result is a proliferation of Th1 cells and overproduction of Th1 related cytokines (mainly IFN-gamma and TNF-alpha). Feedback mechanisms of these cytokines cause a suppression of the Th2 lymphocytes and a reduction of Th2 cytokine production (mainly IL-4, IL-5, IL-10 and IL-13). The end result is a reduction in the ability of the infected host to mount an adequate immune response to invading organisms that require a predominantly Th2 dependant response (these include parasitic infections and production of mucosal and humoral antibodies).

Sincalide corresponds to the C-terminal octapeptide of cholecystokinin (CCK) which acts on receptors within the gallbladder wall causing it to contract.
Cholecystokinin (CCK) is a hormone originally isolated from porcine intestinal mucosa and described as a linear 33-amino acid peptide containing a sulfated tyrosine, which is essential for its biological activity. It has been found in mammals in both the digestive tract and the central nervous system. Among its multiple biological functions, this hormone stimulates pancreatic exocrine secretion, gallbladder contraction, and intestine motility and may also act as a neurotransmitter/neuromodulator in the central nervous system.

4-1BBR is a member of the TNF-receptor superfamily. 4-1BB receptor contributes to the clonal expansion, survival, and development of T cells.4-1BBRcan also induce proliferation in peripheral monocytes, enhance T cell apoptosis induced by TCR/CD3 triggered activation, and regulate CD28 co-stimulation to promote Th1 cell responses. The expression of this receptor is induced by lymphocyte activation. TRAF adaptor proteins have been shown to bind to this receptor and transduce the signals leading to activation of NF-kappaB.

Decorin (DCN) is a small cellular or pericellular matrix proteoglycan which is closely related in structure to biglycan protein. Decorin is a secreted protein which binds to collagen and fibronectin in extracellular matrix. Decorin appears in different glycoforms, substituted with chondroitin sulfate or dermatan sulfate consistent with the original tissue. DCN contains one attached glycosaminoglycan chain. Decorin influences the rate of fibril formation. Decorin is capable of suppressing the growth of various tumor cell lines. DCN gene defects cause corneal dystrophy. The DCN gene is a candidate gene for Marfan syndrome.

Serpin Peptidase Inhibitor, Clade A Member 8 (SERPINA8), which is a pre-angiotensinogen or angiotensinogen precursor, is expressed in the liver and cleaved by the enzyme renin in response to lowered blood pressure. The ensuing product, angiotensin I, is at that point cleaved by angiotensin converting enzyme (ACE) to produce the physiologically active enzyme angiotensin II. SERPINA8 protein is involved in maintaining blood pressure and in the pathogenesis of essential hypertension and preeclampsia. SERPINA8 gene mutations are linked with susceptibility to essential hypertension, and may cause renal tubular dysgenesis, which is a severe disorder of renal tubular development. Defects in the SERPINA8 gene are also linked with non-familial structural atrial fibrillation, and inflammatory bowel disease.

Neurotensin (NTS) is a common precursor for 2 peptides, neuromedin N and neurotensin. Neurotensin is a secreted tridecapeptide, which is generally distributed throughout the central nervous system, and may serve as a neurotransmitter or a neuromodulator. NTS is involved in dopamine-associated pathophysiological events, in the maintenance of gut structure and function, and in the regulation of fat metabolism. Tissue-specific processing may initiate the formation in some tissues of larger forms of neuromedin N and neurotensin. The large forms may embody more stable peptides which are also biologically active.

TIPIN is a member of the CSM3 family. TIPIN protein is essential for normal advancement of S-phase and vital for cell existence after DNA damage or replication stress. TIPIN is specifically necessary for the ATR - CHEK1 pathway in the replication checkpoint induced by ultraviolet light.

Carbohydrate Sulfotransferase 10, also known as CHST10 is a member of the sulfotransferase 2 family. CHST10 was first recognized as a sulfotransferase which acts on the human natural killer-1 (HNK-1) glycan. Furthermore, CHST10 is a carbohydrate involved in neurodevelopment as well as synaptic plasticity.

WAP four-disulfide core domain protein 2 (WFDC2) is a protease inhibitor, which belongs to the WFDC domain family. WFDC2 is effective with a broad range of proteases, e.g. aspartic, serine or thiol proteases. WFDC2 is expressed in several normal tissues, including the male reproductive system, regions of the respiratory tract and nasopharynx. WFDC2 may be involved in sperm maturation. WFDC2 is also highly expressed in a number of tumors cells lines, such ovarian, colon, breast, lung and renal cells lines.

Uteroglobin (SCGB1A1) which belongs to the Secretoglobin (SCGBs) superfamily, is a multifunctional protein that exerts anti-inflammatory and anti-tumorigenic effects by binding small hydrophobic molecules such as phospholipids and prostaglandins. Uteroglobin is involved in numerous functions including anti-inflammation, inhibition of phospholipase A2 and the sequestering of hydrophobic ligands. SCGB1A1 is expressed by Clara cells, the non-ciliated, non-mucous secretory cells predominant in lung bronchioles, and by other epithelia which communicate with the external environment. On top of sequestering pro-inflammatory mediators and carcinogens, Uteroglobin is implicated in the inhibition of cell migration and invasion, platelet aggregation, and T cell differentiation. SCGB1A1 gene defects are associated with a susceptibility to asthma.

Fetuin is a liver-produced negative acute phase protein composed of two subunits, the A and B chains.
Fetuin homologs have been identified in several species including rat, sheep, pig, rabbit, guinea pig, cattle, mouse and human. Multiple physiological roles for these homologs have been suggested, including ability to bind to hydroxyapatite crystals and to specifically inhibit the tyrosine kinase (TK) activity of the insulin receptor (IR).
Fetuin-A (alpha2-Heremans-Schmid glycoprotein; AHSG) is an important circulating inhibitor of calcification in vivo, and is downregulated during the acute-phase response.
Sera from patients on long-term dialysis with low AHSG concentrations showed impaired ex-vivo capacity to inhibit CaxPO4 precipitation.
Fetuin may influence the resolution of inflammation by modulating the phagocytosis of apoptotic cells by macrophages.
ASHG blocks TGF-beta-dependent signaling in osteoblastic cells, and mice lacking ASHG display growth plate defects, increased bone formation with age, and enhanced cytokine-dependent osteogenesis.

Sorcin (SRI) which is a 22kDa calcium-binding protein was originally identified in multidrug-resistant cells. Sorcin, which modulates excitation-contraction coupling in the heart, contributes to calcium homeostasis in the heart sarcoplasmic reticulum.

Tachykinin-3 belongs to the substance P-related tachykinin family. Tachykinins are active peptides that stimulate neurons, induce behavioral responses, are effective vasodilators and secretagogues, and contract (directly or indirectly) many smooth muscles. TAC3 and its receptor are essential switches of regulator of human puberty, regulated by the brain through the release of the GnRH which starts a chain of processes which eventually lead to the production of sex hormones.
During pregnancy, the expression of TAC3 is restricted to the outer syncytiotrophoblast of the placenta, significant concentrations of TAC3 can be identified in plasma as early as week 9, and plasma concentrations of TAC3 are grossly elevated in pregnancy-induced hypertension and pre-eclampsia. Higher Tachykinin-3 concentrations in normotensive pregnant women may be caused by the advanced gestational age and/or the result of a negative interaction of other vasoactive substances. TAC3 has a role in the continuance of high placental blood flow in normal pregnancy.

CCAAT/enhancer binding protein(C/EBP) g is a family of transcription factors all contain a highly conserved, basic-leucine zipper domain at the C-terminus that is involved in dimerization and DNA binding. C/EBP family of transcription factors regulates viral and cellular CCAAT/enhancer element-mediated transcription. C/EBP family consist of several related proteins, C/EBP a,b,g,d, that form homodimers and/or form heterodimers with each other. C/EBP proteins contain the bZIP region, which is characterized by two motifs in the C-terminal half of the protein; a basic region involved in DNA binding and a leucine zipper motif involved in dimerization. C/EBP g may cooperate with Fos to bind PRE- enhancer elements.

Geminin is a 25 kDa nuclear protein, which inhibits DNA replication and is degraded during the mitotic phase of the cell cycle. Geminin controls replication by binding to the licensing factor Cdt1, and is involved in neural differentiation. In addition, Geminin directly interacts with Six3 and Hox homeodomain proteins during embryogenesis and inhibits their functions. Geminin can also promote DNA replication. Geminin has 2 roles in 2 different stages of the cell cycle: Geminin is a negative regulator of DNA replication during the “S phase” of the cell cycle. Inhibition of Geminin during the “S phase” (by RNAi) results in an additional round of replication of portions of the genome. During the “M phase” of the cell cycle (mitosis) Geminin stabilizes the replication factor Cdt1 promoting DNA replication during the next cell cycle. Moreover, inhibition of Geminin during mitosis (by RNAi) causes destabilization of Cdt1 protein and impairment of DNA replication during the next cell cycle. Geminin thus guarantees that only one round of replication occurs during each cell cycle. It was discovered that Geminin is overexpressed in a number of malignancies and cancer cell lines. This maintains the concept that Geminin has also a positive role in DNA replication and cell cycle progression. Geminin accumulates through S, G2 and M phases of the cell cycle but is absent during the G1 phase. During the metaphase/anaphase transition of mitosis Geminin levels decrease.

Zinc Finger Protein 689 (ZNF689) is a member of the krueppel C2H2-type zinc-finger protein family. The ZNF689 protein contains 12 C2H2-type zinc fingers and 1 KRAB domain. ZNF689 may be involved in transcriptional regulation.

Secreted frizzled-related protein 2 (SFRP2) belongs to the SFRP family which contains a cysteine-rich domain homologous to the putative Wnt-binding site of Frizzled proteins. SFRP2 functions as soluble modulators of Wnt signaling. Methylation of SFRP2 might indicate on colorectal cancer.

AMTN is a member of the amelotin family. AMTN is a lately discovered secreted enamel protein. AMTN mainly expressed during the maturation stage of enamel formation. AMTN gathers in a basal lamina-like structure at the interface between ameloblasts and enamel mineral and it co-localizes with one more lately described enamel protein, odontogenic ameloblast- related protein (ODAM(.

Secreted Protein Acidic & Rich in Cysteine (SPARC) protein is coded by the SPARC gene in humans. SPARC is a glycoprotein located in bones that binds to calcium. SPARC is produced by fibroblasts, capillary endothelial cells, platelets and macrophages, mainly in areas of tissue morphogenesis and remodelling. Asides from calcium, SPARC can also bind to collagen.

SPARC protein, or secreted protein acidic and rich in cysteine, or osteonectin or basement-membrane protein 40 is a protein that is coded by the SPARC gene in humans. It is a glycoprotein located in bones, that binds to calcium. The osteonectin is secreted from osteoblasts cells when boas are formed, mineralized and promotes the formation and creation of mineral crystals. Asides from calcium, it has been shown that this protein can also bind to collagen.

Serine/arginine-rich splicing factor 1 (SFRS1) belongs to the arginine/serine-rich splicing factor protein family, and functions in both constitutive and alternative pre-mRNA splicing. SFRS1 binds to pre-mRNA transcripts and components of the spliceosome, and can either initiate or inhibit splicing depending on the position of the pre-mRNA binding site. The ability of SFRS1 to activate splicing is controlled by phosphorylation and interactions with other splicing factor associated proteins.