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The FGFs are a family of more than 20 small (~17–26 kDa) secreted peptides. The initial characterization of these proteins focused on their ability to stimulate fibroblast proliferation. This mitogenic activity was mediated through FGF receptors (FGFRs) 1, 2, or 3. A fourth closely related tyrosine kinase receptor (FGFR4) was able to bind the FGFs but did not lead to a mitogenic response.
FGFs modulate cellular activity via at least 5 distinct subfamilies of high-affinity FGF receptors (FGFRs): FGFR-1, -2, -3, and -4, all with intrinsic tyrosine kinase activity and, except for FGFR-4, multiple splice isoforms, and FGFR-5, which lacks an intracellular kinase domain. There is growing evidence that FGFRs can be important for regulation of glucose and lipid homeostasis. The overexpression of a dominant negative form of FGFR-1 in ? cells leads to diabetes in mice, which thus implies that proper FGF signaling is required for normal ? cell function and glycemia maintenance. FGFR-2 appears to be a key molecule during pancreatic development. Moreover, FGFR-4 has been implicated in cholesterol metabolism and bile acid synthesis.
FGF-19, has been shown to cause resistance to diet-induced obesity and INS desensitization and to improve INS, glucose, and lipid profiles in diabetic rodents. Since these effects, at least in part, are mediated through the observed changes in metabolic rates, FGF-19 can be considered as a regulator of energy expenditure.
FGF-21 is preferentially expressed in liver, but an exact knowledge of FGF-21 bioactivity and its mode of action have been lacking to date. FGF-21 is a potent activator of glucose uptake on adipocytes, protects animals from diet-induced obesity when overexpressed in transgenic mice, and lowers blood glucose and triglyceride levels when therapeutically administered to diabetic rodents.

PEX19 is vital for peroxisome biogenesis in Saccharomyces cerevisiae. PEX19 is limited to the outer surface of peroxisomes in liver cells and is has a part in the early stage of peroxisome membrane assembly, prior to the import of matrix protein.

Platelet factor-4 is a 70-amino acid protein that is released from the alpha-granules of activated platelets and binds with high affinity to heparin. Its major physiologic role appears to be neutralization of heparin-like molecules on the endothelial surface of blood vessels, thereby inhibiting local antithrombin III activity and promoting coagulation. As a strong chemoattractant for neutrophils and fibroblasts, PF4 probably has a role in inflammation and wound repair. Oncostatin-A is a member of the CXC chemokine family. Human PF4 is used for the proof of heparin-induced thrombocytopenia. Furthermore it is used as an inhibitor in the angiogenesis during tumor therapy.

MANF is a 20kDa protein which belongs to the ARMET family. MANF was originally known as an arginine-rich region protein which was extremely mutated in a large number of tumors. MANF Expression is induced during ER stress, signifying that MANF takes part in protein quality control during ER stress.

IL-9 is a factor which is thought to be a regulator of hematopoiesis. It has been shown to enhance the growth of human mast cells and megakaryoblastic leukemic cells as well as murine helper t-cell clones. IL-9 is a glycoprotein with a molecular weight of 32-39 that is derived from T-cells, and maps to human chromosome 5.

GDF-5 is a member of the bone morphogenetic protein (BMP) family and the TGF-beta superfamily. This group of proteins is characterized by a polybasic proteolytic processing site which is cleaved to produce a mature protein containing seven conserved cysteine residues. The members of this family are regulators of cell growth and differentiation in both embryonic and adult tissues. Mutations in this gene are associated with acromesomelic dysplasia, Hunter-Thompson type; brachydactyly, type C; and chondrodysplasia, Grebe type. These associations confirm that the gene product plays a role in skeletal development.

EIF5A is the single protein identified to contain remarkable amino acid formed by the action of deoxyhypusine synthase and deoxyhypusine hydroxylase using spermidine as the substrate. EIF5A takes part in the first step of peptide bond formation in translation, nevertheless further experiments implicates it as a universally conserved translation elongation factor. Modulation of EIF5A is connected to proliferation and cancer. Expression of EIF-5A is upregulated in the PBMCs of HIV-1 patients. EIF5A coordinates significant cellular processes like cell viability and senescence during its effects on the stability of certain mRNAs. Heat stress-induced loss of EIF-5A in a human pancreatic cancer cell line. EIF5A stability takes part in determining the fate of the particular cell type after severe heat stress.

TNFR2 belongs to the TNF-receptor superfamily. TNFR2 is receptor with high affinity for TNFSF2/TNF-alpha and approximately 5-fold lower affinity for homotrimeric TNFSF1/lymphotoxin-alpha. TNFR2 mediates the majority of the metabolic effects of TNF-alpha. In addition, knockout studies in mice propose a role for TNFR2 in protecting neurons from apoptosis by stimulating antioxidative pathways. TNFR2 expression might have a significant role in the angiogenesis, tumor cell proliferation and metastasis of Invasive micropapillary carcinoma of the breast.
There are 2 types of soluble TNF receptors: sTNFR-I and sTNFR-II, which act to neutralize the biological activities of TNF alpha and TNF beta. The levels of these soluble receptors seem to increase as a result of shedding of the extracellular domains of the membrane bound receptors. High levels of soluble TNF receptors are found in the amniotic fluid of pregnant women. TNFR2 and TNFR1 form a heterocomplex which mediates the recruitment of 2 anti-apoptotic proteins, c-IAP1 and c-IAP2, which possess E3 ubiquitin ligase activity. IAPs’ function in TNF-receptor signaling is unknown; nevertheless, c-IAP1 is believed to potentiate TNF-induced apoptosis by the ubiquitination and degradation of TNF-receptor-associated factor 2, which mediates anti-apoptotic signals. Oxidative stress promotes TNFR1 and TNFR2 self-interaction, ligand-independent and enhanced ligand-dependent TNF signaling. TNF-a, TNFR1 and TNFR2 have roles in cellular differentiation. TNFR1 and TNFR2 function in cell type-specific renal injury.

TNFRSF14, a member of the TNF receptor superfamily, is a type I transmembrane protein. TNFRSF14 is expressed in peripheral blood T cells, B cells, monocytes and in various tissues enriched in lymphoid cells. TNFRSF14 operates as a co-stimulatory factor for the activation of lymphoid cells and as a deterrent to infection by herpesvirus. Additionally, TNFRSF14 encourages the proliferation of T cells, and triggers apoptosis of various tumor cells.

Fibroblast growth factor 18 (FGF18) is a member of the large FGF family which has at least 23 members. FGF18 is a heparin binding growth factor with a core 120 amino acid FGF domain which allows for a common tertiary structure. FGFs are expressed in the course of the embryonic development and in restricted adult tissues. FGF-18 is an indispensable regulator of long bone and calvarial development. FGF-18 signals via FGFR 1c, 2c, 3c, and 4.

Excess adiposity is the most important risk in the development of insulin resistance and type 2 diabetes mellitus (T2DM). Adipose tissue produces several proteins (adipocytokines) such as leptin, adiponectin, resistin, tumor necrosis factor-?, and IL-6, that modulate insulin sensitivity and appear to play an important role in the pathogenesis of insulin resistance, diabetes, dyslipidemia, inflammation, and atherosclerosis. However, the mechanisms by which fat tissue induces insulin resistance and the role of adipocytokines in the pathogenesis of T2DM have not been well established.
Visfatin, also known as pre-B cell colony-enhancing factor (PBEF), is a cytokine that is highly expressed in visceral fat and was originally isolated as a secreted factor that synergizes with IL-7 and stem cell factors to promote the growth of B cell precursors. Visfatin homologs have been identified in carp, invertebrate mollusks, and bacteria, as well as in vertebrates, including humans and the mouse. It has been postulated to play a role in innate immunity.
Visfatin exerts insulin-mimetic effects that are dose-dependent and quantitatively similar to those of insulin in stimulating muscle and adipocyte glucose transport, and in inhibiting hepatocyte glucose production. Intravenous injection of recombinant visfatin in mice decreased plasma glucose in a dose-dependent fashion. In keeping with its insulin-mimetic effects, visfatin was as effective as insulin in reducing hyperglycemia in insulin-deficient diabetic mice. Visfatin was also found to be bound to and activate insulin receptor, causing receptor phosphorylation and the activation of downstream signaling molecules. However, visfatin and insulin did not compete for binding to the insulin receptor, indicating that the two proteins were recognized by different regions of the receptor. Thus, visfatin might play a role in glucose homeostasis and dysregulation in biosynthesis or signal transduction, and might contribute to the pathogenesis of diabetes.

Acidic fibroblast growth factor is a member of the fibroblast growth factor (FGF) family. FGF family members possess broad mitogenic and cell survival activities, and are involved in a variety of biological processes, including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. FGF1 functions as a modifier of endothelial cell migration and proliferation, as well as an angiogenic factor.FGF1 acts as a mitogen for a variety of mesoderm- and neuroectoderm-derived cells in vitro, thus is thought to be involved in organogenesis. Three alternatively spliced variants encoding different isoforms have been described. The binding growth factors are angiogenic agents in vivo and are potent mitogens for a variety of cell types in vitro. There are differences in the tissue distribution and concentration of these 2 growth factors.

Rat and mouse FGF-9 show a very high homology to human FGF-9. The transcripts for FGF-9 have been found in brain and in kidney tissue. Fibroblast Growth Factor-9 is a member of the fibroblast growth factor (FGF) family. FGF family members possess broad mitogenic and cell survival activities, and are involved in a variety of biological processes, including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. FGF9 was isolated as a secreted factor that exhibits a growth-stimulating effect on cultured glial cells. In nervous system, this protein is produced mainly by neurons and may be important for glial cell development. Expression of the mouse homolog of this gene was found to be dependent on Sonic hedgehog (Shh) signaling. Mice lacking the homolog gene displayed a male-to-female sex reversal phenotype, which suggested a role in testicular embryogenesis Fibroblast Growth Factor 9 may have a role in glial cell growth and differentiation during development, gliosis during repair and regeneration of brain tissue after damage, differentiation and survival of neuronal cells, and growth stimulation of glial tumors.

Fibroblast Growth Factor 17 (FGF17) belongs to the fibroblast growth factor (FGF) family. FGF family members have broad mitogenic and cell survival activities, and are involved in various biological processes including embryonic development cell growth, morphogenesis, tissue repair, tumor growth and invasion. The FGF17 gene is highly expressed in the cerebellum and cortex. The mouse homolog of the FGF17 gene is localized to specific sites in the midline structures of the forebrain, the midbrain-hindbrain junction, developing skeleton and developing arteries, suggesting a role in central nervous system, bone and vascular development.

SF3B14 is a 125 amino acid nuclear protein which is a component of the splicing factor 3b complex. Splicing factor 3b is involved with s with both the U2 and U11/U12 small nuclear ribonucleoprotein complexes (U2 snRNP) of spliceosomes. SF3B14 which is required for the splicing of pre-mRNA enters the spliceosome and connect with the pre-mRNA branch site facilitating the interaction of snRNP with the branch sites of U2 and U12 of the 17S U2 and the 18S U11/U12 snRNP complex.

GMFB is part of the GMF subfamily of the larger actin-binding protein ADF family. GMFB is phosphorylated after phorbol ester stimulation, and is crucial for the nervous system. GMFB causes brain cell differentiation, stimulates neural regeneration and inhibits tumor cell proliferation. GMFB overexpression in astrocytes results in the increase of BDNF production. GMFB expression is increased by exercise, thus BDNF is important for exercise-induction of BDNF.

CMC4 is a downstream 8kDa protein restricts to mitochondria which was identified by participation in some t(X;14) translocations related with mature T-cell proliferations. This region has a compound gene structure, with a common promoter and 5’ exon spliced to two different groups of 3’ exons which encode 2 separate proteins.

TNFRSF13B (TACI) is a transmembrane receptor protein found predominantly on the surface of B cells (a significant part of the immune system). TACI was at first discovered owing to its ability to interact with calcium-modulator and cyclophilin ligand (CAML). Later on, it was found that TACI plays a key role in humoral immunity by interacting with two members of the TNF family. Also, TACI controls T cell-independent B cell antibody responses, isotype switching, and B cell homeostasis.

Herpesvirus entry mediator or HVEM or tumour necrosis factor receptor superfamily member 14 or TNFRSF14, is part of the TNF receptors family that is a receptor located on the cell surface. The cytoplasmic area of this receptor can bind all sorts of TNF receptor associated factor (TRAF) protein. Those proteins can mediate pathways activating an immune response. The MITF is regulating TNFRSF14 gene expression.

Factor that is thought to be a regulator of hematopoiesis. It has been shown to enhance the growth of human mast cells and megakaryoblastic leukemic cells as well as murine helper t-cell clones. IL-9 is a glycoprotein with a molecular weight of 32-39 that is derived from T-cells, and maps to human chromosome 5.

TNFR2 belongs to the TNF-receptor superfamily. TNFR2 is receptor with high affinity for TNFSF2/TNF-alpha and approximately 5-fold lower affinity for homotrimeric TNFSF1/lymphotoxin-alpha. TNFR2 mediates the majority of the metabolic effects of TNF-alpha. In addition, knockout studies in mice propose a role for TNFR2 in protecting neurons from apoptosis by stimulating antioxidative pathways. TNFR2 expression might have a significant role in the angiogenesis, tumor cell proliferation and metastasis of Invasive micropapillary carcinoma of the breast.
There are 2 types of soluble TNF receptors: sTNFR-I and sTNFR-II, which act to neutralize the biological activities of TNF alpha and TNF beta. The levels of these soluble receptors seem to increase as a result of shedding of the extracellular domains of the membrane bound receptors. High levels of soluble TNF receptors are found in the amniotic fluid of pregnant women. TNFR2 and TNFR1 form a heterocomplex which mediates the recruitment of 2 anti-apoptotic proteins, c-IAP1 and c-IAP2, which possess E3 ubiquitin ligase activity. IAPs’ function in TNF-receptor signaling is unknown; nevertheless, c-IAP1 is believed to potentiate TNF-induced apoptosis by the ubiquitination and degradation of TNF-receptor-associated factor 2, which mediates anti-apoptotic signals. Oxidative stress promotes TNFR1 and TNFR2 self-interaction, ligand-independent and enhanced ligand-dependent TNF signaling. TNF-a, TNFR1 and TNFR2 have roles in cellular differentiation. TNFR1 and TNFR2 function in cell type-specific renal injury.

Insulin-like growth factor-binding protein 4 (IGFBP-4) is a part of the insulin-like growth factor binding protein (IGFBP) family. IGFBP4 includes an IGFBP domain and a thyroglobulin type-I domain. IGFBP4 binds both insulin-like growth factors (IGFs) I and II. IGFBP-4 circulates in the plasma in both glycosylated and non-glycosylated forms. IGFBPs can either inhibit or enhance the biological activities of IGF, or act in an IGF independent manner. IGFBP-4 is consistently inhibits several cancer cells in vivo and in vitro, suggesting that it may function as an apoptotic factor. IGFBP4 is produced by all colon cancer cells. Binding of IGFBP-4 prolongs the half-life of the IGFs and changes their interaction with cell surface receptors.

TNF-related apoptosis-inducing ligand (TRAIL) is a ligand molecule which induces apoptosis. It is a type II transmembrane protein with homology to other members of the tumor necrosis factor family.
In humans, the gene that encodes for TRAIL is located at chromosome 3q26.
TRAIL binds to the death receptors, DR4 and DR5. The process of apoptosis is caspase-8-dependent. This protein preferentially induces apoptosis in transformed and tumor cells, but does not appear to kill normal cells although it is expressed at a significant level in most normal tissues.

Insulin-like Growth Factor-Binding Protein 7 (IGFBP7) is a member of the IGFBP family. IGFBP family members are all cysteine rich proteins with conserved cysteine and have an IGFBP domain, a Kazal-like domain and an Ig-like C2-type domain. IGFBP7 is expressed in a broad range of normal human tissues and it mostly shows reduced expression in cancer cell lines of prostate, breast, colon, and lung origin. IGFBP7 has a role in skeletal myogenesis by binding to IGF in a manner which inhibits IGF induced differentiation of skeletal myoblasts, without disturbing IGF induced proliferation. Moreover, IGFBP7 suppresses growth and colony formation of prostate and breast cancer cell lines via an IGF independent mechanism, which triggers a delay in the G1 phase of the cell cycle, and increased apoptosis.