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The PI3Kb isoform can be activated by insulin via the insulin receptor to initiate a cascade of events that control cell growth and metabolism. The activation of
PI3Kb is mediated by the p85 regulatory subunit binding to tyrosine phosphorylated insulin receptor substrate (IRS) proteins (e.g. IRS-1 and IRS-2).
It was also shown that PI3Kb is involved in apoptosis in human colon carcinoma cells. Injection of neutralizing antibodies specific to p110b in WiDr,
HCT116 and CO 115 adenocarcinoma cells inhibited de novo DNA synthesis.
PI3Kb is the major PI3K isoform required for apoptotic cell and Fc-g receptor mediated phagocytosis shown for primary mouse macrophages and the Jurkat human leukemia T cell line.
It was shown by several research groups that the catalytic subunit of PI3Kb can be activated by Gbg subunits of G-protein coupled receptors.

Prolactin is a neuroendocrine hormone synthesized primarily by the pituitary gland but also a variety of other cell types including the placenta, brain and uterus. Prolactin is secreted when eating, nursing, mating, estrogen treatment and during ovulation. Prolactin's primary role is to promote and maintain lactation but also plays a role in breast cancer development, regulation of reproductive function and immunoregulation.

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.

IFN-gamma produced by lymphocytes activated by specific antigens or mitogens.
IFN-gamma, in addition to having antiviral activity, has important immunoregulatory functions, it is a potent activator of macrophages, and has antiproliferative effects on transformed cells and it can potentiate the antiviral and antitumor effects of the type I interferons.

FHIT enzyme cleaves adenosine 5'' PPP 5'' A to yield AMP and ADP. FHIT gene includees the regular fragile site FRA3B on chromosome 3. Alterations and deletions of the FHIT gene are highly linked to the genesis and establishment of human tumors of the lung, cervix, breast, colon, stomach and pancreas. In normal cells, FHIT functions as a tumor suppressor and physically relates with ubiquitin conjugating enzyme 9.

Thioredoxins are small disulphide-containing redox proteins (within the conserved Cys-Gly-Pro-Cys active site) that have been found in all the kingdoms of living organisms. Thioredoxin contains a single disulfide active site and serves as a general protein disulphide oxidoreductase. Thioredoxins are involved in the first unique step in DNA synthesis. It interacts with a broad range of proteins by a redox mechanism based on reversible oxidation of two cysteine thiol groups to a disulphide, accompanied by the transfer of two electrons and two protons. The net result is the covalent interconversion of a disulphide and a dithiol. It has been suggested that thioredoxin may catalyze the formation of correct disulfides during protein folding because of its ability to act as an efficient oxidoreductant. Trx also provides control over a number of transcription factors affecting cell proliferation and death through a mechanism referred to as redox regulation.

Leptin is a protein hormone. It is mainly produced in adipose cells that regulate energy homeostasis by restraining hunger. Leptin ties to nuclear receptors in the hypothalamus (arcuate nucleus). Similar to insulin resistance in type II diabetes, in obesity there is a decrease in the sensitivity towards leptin, ending in a failure to identify satiety, even in high levels of energy stores or leptin itself. Full-length cDNA encoding 2 leptin sequences (tLepA and tLepB) and 1 leptin receptor sequence (tLepR) exists in tilapia (Oreochromis niloticus). The full-length cDNA of tLepR is 3423 bp, encoding a protein of 1140 amino acid which contained all functionally important domains conserved among vertebrate leptin receptors. The cDNAs of tLepA and tLepB are 486 bp and 459 bp in length, encoding proteins of 161 aa and 152 aa, respectively. The three-dimensional structures of tLepA and tLepB demonstrates strong conservation of tertiary structure with that of human leptin comprised of 4 helixes.

Leptin is a protein hormone. It is mainly produced in adipose cells that regulate energy homeostasis by restraining hunger. Leptin ties to nuclear receptors in the hypothalamus (arcuate nucleus). Similar to insulin resistance in type II diabetes, in obesity there is a decrease in the sensitivity towards leptin, ending in a failure to identify satiety, even in high levels of energy stores or leptin itself. Full-length cDNA encoding 2 leptin sequences (tLepA and tLepB) and 1 leptin receptor sequence (tLepR) exists in tilapia (Oreochromis niloticus). The full-length cDNA of tLepR is 3423 bp, encoding a protein of 1140 amino acid which contained all functionally important domains conserved among vertebrate leptin receptors. The cDNAs of tLepA and tLepB are 486 bp and 459 bp in length, encoding proteins of 161 aa and 152 aa, respectively. The three-dimensional structures of tLepA and tLepB demonstrates strong conservation of tertiary structure with that of human leptin comprised of 4 helixes.

Natriuretic Peptide A (NPPA) is a part of the natriuretic peptide family and is involved in cardiovascular homeostasis through regulation of natriuresis, diuresis, and vasodilation. NPPA is synthesized as a great precursor which releases a peptide from the N-terminus with similarity to vasoactive peptide, cardiodilatin, and another peptide from the C-terminus with natriuretic-diuretic activity. In female pregnancy, NPPA is promoting trophoblast invasion and spiral artery remodeling in uterus.

SPARC, an acronym for “secreted protein, acidic and rich in cysteine”, is also known as osteonectin or BM-40. It is the founding member of a family of secreted matricellular proteins with similar domain structure. The 303 amino acid, 43 kDa protein contains a 17 aa signal sequence, an N-terminal acidic region that binds calcium, a follistatin domain containing Kazal-like sequences, and a C-terminal extracellular calcium (EC) binding domain with two EF-hand motifs. SPARC is produced by fibroblasts, capillary endothelial cells, platelets and macrophages, especially in areas of tissue morphogenesis and remodeling. SPARC shows context-specific effects, but generally inhibits adhesion, spreading and proliferation, and promotes collagen matrix formation. For endothelial cells, SPARC disrupts focal adhesions and binds and sequesters PDGF and VEGF. SPARC is abundantly expressed in bone, where it promotes osteoblast differentiation and inhibits adipogenesis.

Hexokinases phosphorylate glucose to produce glucose-6-phosphate, thus committing glucose to the glycolytic pathway. Hexokinase1 encodes a ubiquitous form of hexokinase which localizes to the outer membrane of mitochondria. Mutations in this gene have been associated with hemolytic anemia due to hexokinase deficiency. Alternative splicing of HXK1 results in five transcript variants which encode different isoforms, some of which are tissue-specific. Each isoform has a distinct N-terminus; the remainder of the protein is identical among all the isoforms. A sixth transcript variant has been described, but due to the presence of several stop codons, it is not thought to encode a protein.

Cytokeratin 8 (KRT8) belongs to the type II keratin family clustered on the long arm of chromosome 12. Type I and type II keratins heteropolymerize to form intermediate-sized filaments in the cytoplasm of epithelial cells. KRT8 typically dimerizes with keratin 18 to form an intermediate filament in simple single-layered epithelial cells. KRT8 has a role in retaining cellular structural integrity and also functions in signal transduction and cellular differentiation. KRT8 gene mutations cause cryptogenic cirrhosis.

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.

Filamin is a large (270kd) dimeric actin crosslinking protein from a variety of sources, which helps to stabilize the 3D cortical actin network. The fundamental structure of filamin is well conserved and consists of an actin binding domain at the N-terminus followed by a C-terminal rod domain consisting of numerous repeat segments ranging from 4 in C. elegans to 24 in mammalian cells. Each repeat in the rod domain consists of roughly 100 residues and forms an immunoglobulin like fold. Such immunoglobulin folds have been found in a variety of proteins and are responsible for protein-protein interactions. Filamin Human actin-binding protein (ABP), aka filamin, crosslinks actin filaments into orthogonal networks in cortical cytoplasm and participates in the anchoring of membrane proteins for the actin cytoskeleton. Mammalian filamin interacts directly with at least 30 proteins such as transmembrane receptors, second messenger-associated proteins, protein kinases, phosphatases and cytoskeletal proteins and these interactions have been shown to require one or more of the repeat elements in the rod domain.

AKR7A3, takes part in the detoxification of aldehydes and ketones. AKR7A3 reduces the dialdehyde protein-binding form of aflatoxin B1 (AFB1) to the non-binding AFB1 dialcohol. AKR7A3 participates in protection of liver against the toxic and carcinogenic effects of AFB1, a potent hepatocarcinogen.

AK3L1 is an affiliate of the adenylate kinase family of enzymes. AK3L1 enzyme is restricted to the mitochondrial matrix. Adenylate kinases-3 regulates the adenine and guanine nucleotide compositions within a cell by means of catalyzing the reversible transfer of phosphate group among these nucleotides. 5 different isozymes of adenylate kinase have been identified in vertebrates. The enzyme expression of various adenylate kinase isozymes is growth regulated and tissue-specific.

Pyruvate kinase is a key enzyme in the glycolytic pathway. The M2 isoenzyme of pyruvate kinase is specifically expressed at high levels in tumor cells, and can be measured in plasma of patients with advanced breast cancer. The marker is useful for measuring disease activity, sensitivity to chemotherapy and recurrence.

Gankyrin (proteasome 26S subunit) is a multicatalytic proteinase oncoprotein commonly overexpressed in most hepatocellular carcinomas. Proteasomes are found throughout eukaryotic cells at a high concentrations and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. Gankyrin interacts with S6 ATPase of the 19S regulatory particle of the 26S proteasome. Gankyrin is involved in theregulation of the phosphorylation of the retinoblastoma protein by CDK4, and to enhance the ubiquitinylation of p53 by MDM2. Gankyrin consists of 7 ankyrin repeats and is structurally similar to I kappa Bs. Gankyrin acts as a regulatory subunit of the 26s proteasome which is involved in the atp-dependent degradation of ubiquitinated proteins. Gankyrin is involved in progression of esophageal squamous cell carcinoma. gankyrin plays an oncogenic role especially in early stages of human epatocarcinogenesis. Gankyrin binds to NF-kappaB and suppresses its activity at the transcription level by modulating acetylation through SIRT1. Structural comparison between Gankyrin & p16(INK4A) identified numerous residues of gankyrin that are potentially important for CDK4 binding.

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.

Follicle stimulating hormone (FSH) is a hormone synthesised and secreted by gonadotropes in the anterior pituitary gland. FSH and LH act synergistically in reproductionIn women, in the ovary FSH stimulates the growth of immature Graafian follicles to maturation. As the follicle grows it releases inhibin, which shuts off the FSH production.
In men, FSH enhances the production of androgen-binding proteinby the Sertoli cells of the testes and is critical for spermatogenesis.
In both males and females, FSH stimulates the maturation of germ cells. In females, FSH initiates follicular growth, specifically affecting granulosa cells. With the concomitant rise in inhibin B FSH levels then decline in the late follicular phase. This seems to be critical in selecting only the most advanced follicle to proceed to ovulation. At the end of the luteal phase, there is a slight rise in FSH that seems to be of importance to start the next ovulatory cycle.
Like its partner, LH, FSH release at the pituitary gland is controlled by pulses of gonadotropin-releasing hormone(GnRH). Those pulses, in turn, are subject to the estrogen feed-back from the gonads.

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.

DKK1 is part of the dickkopf family. DKK1 is a secreted protein with 2 cysteine rich regions and takes part in embryonic development through its inhibition of the WNT signaling pathway. High levels of DKK1 in bone marrow plasma and peripheral blood is associated with the presence of osteolytic bone lesions in patients with multiple myeloma. Induction of DKK1 contributes to the pathological cascade triggered by beta-amyloid and is significantly involved in the development of tau phosphorylation.
DKK1 reduces the differentiation of osteoblastic precursor cells. DKK1 is an important member in multiple myeloma bone disease. DKK1 expression is reduced in human colon tumors, implying that DKK-1 plays a role as a tumor suppressor gene in this neoplasia; the Wnt/beta-catenin pathway is downregulated by the induction of DKK1 expression, a mechanism that is missing in colon cancer.