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PTEN, a tumor suppressor, has been implicated in a large number of human tumors and is conserved from humans to worms. PTEN has a tensin like domain and a catalytic domain similar to that of the dual specificity protein tyrosine phosphatases. Characterization of PTEN protein showed that it is a phosphatase that acts on proteins and on 3-phosphorylated phosphoinositides, and can therefore modulate signal transduction pathways that involve lipid second messengers. In contrast to most of the protein tyrosine phosphatases, PTEN preferentially dephosphorylates phosphoinositide substrates. PTEN negatively regulates intracellular levels of phosphatidylinositol-3,4,5-trisphosphate in cells and acts as a tumor suppressor by negative regulation of AKT/PKB signaling pathway. Recent results indicate that at least part of its role is to regulate the activity of the serine/threonine kinase AKT/PKB, and thus influence cell survival signaling.

Ras-related protein Rab-21 (RAB21) belongs to the Ras superfamily of small GTP-binding proteins. Rab21 is an integrin-associated protein and a positive regulator of integrin traffic. Rab21 associates with the cytoplasmic domains of alpha-integrin chains and their expression influences the endo/exocytic traffic of integrins. This function of Rab21 depends on its GTP/GDP cycle and right membrane targeting.

RAB, Member RAS Oncogene Family-Like 5 (RABL5) belongs to the Ras superfamily of small GTP-binding proteins. The Ras-related superfamily of guanine nucleotide binding proteins includes the R-Ras, Rap, Ral/Rec and Rho/Rab subfamilies. Rab proteins have an essential role in endocytosis or in biosynthetic protein transport. The transporting process of newly synthesized proteins from the endoplasmic reticulum to various stacks of the Golgi complex and to secretory vesicles includes the movement of carrier vesicles and requires Rab protein function.

RAB34 protein which regulates a fast endocytic recycling pathway is restricted to the plasma membrane and endocytic compartments. RAB34 takes part in protein transport, specifically the redistribution of lysosomes to the peri-Golgi region. In fibroblasts, RAB34 protein was co-localized with actin to the membrane ruffles and membranes of moderately large vesicles close to the ruffles.

RAB10, Member RAS Oncogene Family (RAB10) belongs to the Ras superfamily of small GTP-binding proteins. RAB10 is a key regulator of endocytic recycling, particularly in the basolateral recycling pathways of polarized epithelial cells. It is required for the recruitment of CNT-1 to endosomal membranes in the intestinal epithelium.

Phosphatidylinositol-5-Phosphate 4-Kinase, Type II, Beta (PIP4K2B) belongs to the phosphatidylinositol-4-phosphate 5-kinase family.PIP4K2B catalyzes the phosphorylation of phosphatidylinositol-4-phosphate on the 5th hydroxyl of the myo-inositol ring to form phosphatidylinositol-4,5-bisphosphate. PIP4K2B amino acid sequence does not show resemblance to another kinases although PIP4K2B presents kinase activity.PIP4K2B also interacts with p55 TNF receptor.

Rab3A is a member of the small GTPase superfamily, Rab family. Rab3A is a small, Ras-like GTPase expressed in neuroendocrine cells, in which Rab3A is linked with secretory vesicle membranes and regulates exocytosis. Rab3A protein may have a role in neurotransmitter release by regulating membrane flow in the nerve terminal.

Oral cancer-overexpressed protein 1 (ORAOV1) is a candidate oncogene in the 11q13 chromosomal region. Functional analyses showed that ORAOV1 was involved in the regulation of HeLa cell growth via its effect on cell cycle and apoptosis. ORAOV1 is widely expressed; it has a high expression in the placenta, kidney and skeletal muscle. ORAOV1 is amplified and overexpressed in oral cancer cells.

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.

Inhibitor of Growth Family Member 1, also known as ING1 is a tumor suppressor protein which is able to induce cell growth arrest and apoptosis. ING1 is a nuclear protein which physically act together with the tumor suppressor protein TP53 and is a component of the p53 signaling pathway. In addition, Reduced expression and rearrangement of ING1 have been identified in various cancers. Multiple alternatively spliced transcript variants encoding distinct isoforms have been described for ING1.

RHOQ (rho-related GTP-binding protein RhoQ) is a small signaling G protein which cycles between an active GTP-bound and an inactive GDP-bound state. In the active state it binds to a diversity of effector proteins to regulate cellular responses. Ras-like protein belongs to the Rac subfamily of the Rho family of GTPases. RHOQ is involved in epithelial cell polarization processes. In addition, RHOQ plays a role in CFTR trafficking to the plasma membrane. RHOQ causes the formation of thin, actin-rich surface projections called filopodia.

Ras-related protein Rab-2A (RAB2A)is a member of the small GTPase superfamily. RAB protein family members are nontransforming monomeric GTP-binding proteins of the Ras superfamily, which contain four highly conserved regions involved in GTP binding and hydrolysis. In addition, RAB proteins are a fundamental part of endocytic pathways. RAB2A and RAB2B are essential for protein transport from the ER to the Golgi; RAB2A is lipid-anchored to the ER-Golgi intermediate compartment membrane whereas RAB2B is lipid anchored to the cytoplasmic side of the cell membrane. RAB2A also interacts with GOLGA2.

PI3Ka plays a specific role in apoptosis in human colon cancer cells. Injection of neutralizing antibodies specific to PI3Ka into adenocarcinoma cells induced apoptosis, a response that was reverted by treating cells with caspase inhibitor. It was also shown that PI3Ka mediated phosphorylation of the p85a adapter reduces the lipid kinase activity of the heterodimer and this gives hints for PI3K-dependent signaling events not requiring production of 3’-phosphorylated phosphoinositides.
PI3Ka is a key regulator of the initiation of keratinocyte differentiation. A decrease in PI3Ka activity results in a loss of keratinocyte adhesion to the extracellular membrane and the initiation of early phase differentiation.

Peptidase Inhibitor 3, also referred to PI3, is neutrophil and pancreatic elastase-specific inhibitor of skin. The protein may prevent elastase mediated tissue proteolysis. PI3 has shown inhibition of alpha-4-beta-2/CHRNA2-CHRNB2 nicotinic acetylcholine receptor, a weak inhibition on Kv11.1/KCNH2/ERG1 and on the transient receptor potential cation channel subfamily V member 1.

RAB32 is a member of the small GTPase superfamily. RAB32 controls ER calcium management and disturbs the specific enhancement of calnexin on the MAM (mitochondria-associated membrane), however avoids affecting the ER distribution of protein-disulfide isomerase and mitofusin-2. Furthermore, RAB32 regulates the targeting of PKA (cAMP-dependent protein kinase) to mitochondrial and ER membranes and by inactivation or overexpression enhances the phosphorylation of Drp1 and Bad. Using a combination of its functions as a regulator of MAM properties and a PKA-anchoring protein, the activity and expression level of RAB32 define the speed of apoptosis onset.

The hematopoietic growth factor GM-CSF or granulocyte macrophage colony-stimulating factor, stimulates the development of neutrophils & macrophages, enhance proliferation and development of early erythroid megakaryocytic & eosinophilic progenitor cells. GM-CSF is secreted from the fibroblasts, monocytes, T-lymphocytes & endothelial cells. This protein blocks the migration of neutrophils & induces the biological activity of mature end-cells.

The peroxisome proliferator activated receptors (PPARs) are ligandactivated transcription factors within the nuclear receptor superfamily, which play important roles in adipogenesis, glucose homeostasis andinflammation. Three different isotypes can be distinguished; alpha, beta and gamma. PPARg, is mainly expressed in adipose tissue and to lesser extent in colon, the immune system and the retina. Whereas PPARg operates in the catabolism of fatty acids in the liver, PPARg influences the storage of fatty acids in the adipose tissue and plays a role in adipocyte differentiation. PPARg binds to DNA as a heterodimer with retinoid X receptor (RXR), activating expression of target genes after binding ligand.

PDLIM1, a cytoplasmic protein linked to the cytoskeleton, belongs to the enigma protein family. PDLIM1 holds two protein interacting domains - PDZ domain at the amino terminal end and one to three LIM domains at the carboxyl terminal. PDLIM1 enables bringing other LIM interacting proteins to the cytoskeleton. Pseudogenes related to PDLIM1 are situated on chromosomes 3, 14 and 17.

Pirin (PIR) which belongs to the cupin superfamily, is an Fe(II)-containing nuclear protein expressed in all tissues of the body and concentrated within dot-like subnuclear structures. Pirin may function as a transcriptional cofactor and is involved in the regulation of DNA transcription and replication, as a result of interactions with nuclear factor I/CCAAT box transcription factor as well as B cell lymphoma 3-encoded oncoprotein.

Anamorsin, ( CIAPIN) is a member of anamorsin family. CIAPIN mainly expressed in the cytoplasm of liver, pancreas and heart tissue cells and does not show any homology to known apoptosis regulatory molecules of the Bcl-2 or CASP families, or to signal transduction molecules. CIAPIN1 Expression is reliant on growth factor stimulation. It is a ubiquitously expressed protein, and when it is overexpressed, it grants apoptotic resistance.

RAB1B belongs to the RAB protein family, these proteins are low molecular mass monomeric GTPases localized on the cytoplasmic surfaces of distinct membrane bound organelles. RAB1B protein functions in the early secretory pathway and is essential for vesicle transport between the endoplasmic reticulum (ER) and Golgi.

Spi-1 Proto-Oncogene, also known as SPI1, owns ETS-domain transcription factor which activates gene expression during myeloid and Blymphoid cell development. SPI1 binds to a purine-rich sequence called the PU-box which is located near the promoters of target genes, and regulates their expression. SPI1 binds RNA and modulate pre-mRNA splicing. SPI1 is also regulates alternative splicing of target genes.

RAB27B is a member of the RAB family and is an important regulator of vesicular transport. RAB27B is expressed in pituitary tissue, but is more extensively expressed in brain and spleen. RAB27B may be functionally redundant to Rab27a, as it can salvage Rab27a mutants.