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Proteasome subunit alpha type-2 (PSMA2) is a multicatalytic proteinase complex which is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. PSMA2 is a 20S core alpha subunit of proteasome belonging to the peptidase T1A family. PSMA2 functions as a docking domain for the regulatory particles and exterior gates blocking unregulated access to the inner cavity.

Acyl-CoA synthetase family member 2, also known as ACSF2 is a member of the ATP-dependent AMP-binding enzyme family. Acyl-CoA synthetases are a family of enzymes which catalyze the thioesterification of fatty acids with coenzymeA to form activated intermediates, which play a basic part in lipid metabolism as well as homeostasis of lipid-related processes. ACSF2 is required for the complex of lipid synthesis, energy production via beta-oxidation, protein acylation and fatty-acid dependent transcriptional regulation. Moreover, ACSF2 is required for fatty acid import into cells by the process of vectorial acylation.

F-ATPase delta (ATP5D) catalyzes ATP synthesis, employing an electrochemical gradient of protons across the inner membrane during oxidative phosphorylation. ATP synthase is composed of 2 linked multi-subunit complexes: F1-the soluble catalytic core and Fo- the membrane-spanning component, which comprise the proton channel. The catalytic portion of mitochondrial ATP synthase consists of five different subunits (alpha, beta, gamma, delta, and epsilon) assembled with a stoichiometry of 3 alphas, 3 betas, and a single representative of the other three. The proton channel consists of three main subunits-a, b, c. ATP5D is the delta subunit of the catalytic core.

Cyclin-dependent kinase inhibitors (CDKIs) are proteins that bind to and inhibit the activity of CDKs. Two major classes of CDK inhibitors have been identified. The p16 family (p15, p16, p18 and p19) binds to and inhibits the activities of CDK4 and CDK6. The p21 family (p21, p27, p28 and p57) can bind to broad range of CDK-cyclin complexes and inhibit their activities. CDKIs are capable of suppressing growth, and several lines of evidence strongly suggest that at least some CDKIs may be tumor suppressor proteins.

GLRX2 is a multifunctional enzyme with glutathione-dependent oxidoreductase, glutathione peroxidase and glutathione S-transferase (GST) activity. The disulfide bond functions as an electron carrier in the glutathione-dependent synthesis of deoxyribonucleotides by the enzyme ribonucleotide reductase. In addition, it is also involved in reducing cytosolic protein- and non-protein-disulfides in a coupled system with glutathione reductase. Required for resistance to reactive oxygen species (ROS) by directly reducing hydroperoxides and for the detoxification of ROS-mediated damage. Glutaredoxins are a family of glutathione-dependent hydrogen donors that participate in a variety of cellular redox reactions.

Glutaredoxin belongs to the thiol-disulfide oxidoreductase family. Glutraredoxins catalyze the reversible reduction of protein-glutathionyl mixed disulfides to free sulfhydryl groups though a monothiol mechanism. Glutaredoxin-3 (GRX3) is an important protein involved in the regulation of signal transduction, for example during immune cell activation and development of cardiac hypertrophy, apparently in response to redox signals. GRX3 interacts with PRKCQ. GRX3 may have a role in the regulation the function of the thioredoxin system. GRX3 is expressed in the heart, spleen, testis and, to a lower extent, in the thymus and peripheral blood leukocytes. GRX3 is weakly expressed in lung, placenta, colon and small intestine.

Cyclin-dependent kinase 4 combines with the protein cyclin D to form a protein complex that promotes the passage of cells through the G1 checkpoint in the cell growth cycle. This cellular activity is regulated by the protein p16 produced by p16INK4a. Normally, p16 controls cell growth by inhibiting the activity of the CDK4–cyclin D complex and stopping cells at the G1 checkpoint.

Dickkopf-related protein 3 (DKK3) belongs to the DKK protein family including Dkk-1, 2, 3 and -4. DKK3 is a 350 amino acid secreted glycoprotein which is comprised of an N-terminal signal peptide and 2 conserved cysteine-rich domains that are separated by a 12 amino acid linker region. DKK3 is involved in embryonic development through its inhibition of the WNT signaling pathway. DKK3 gene expression is decreased in a variety of cancer cell lines and it may act as a tumor suppressor gene.

Killer Cell lectin-Like Receptor Subfamily K, Member 1 (KLRK1) is an activating receptor which has recently generated considerable interest. The most fascinating of these, are a couple of closely related proteins known as MICA and MICB. These are cell-surface molecules distantly related to MHC class I proteins, and their genes have elements of heat shock promoters. Thus, MICA and MICB are expressed in the course of cell stress and are up-regulated in tumor cells and during viral infections. This receptor-ligand combination has a crucial role in the immune response to various pathologies.

ASS1 is involved in the urea cycle, which is a sequence of chemical reactions that is localized in liver cells. The urea cycle processes excess nitrogen that is generated as the body uses proteins. The surplus nitrogen is used to create a molecule called urea, which is excreted from the body in urine.

Signal transducer and activator of transcription 3 isoform 1, STAT3, ADMIO, DMIO1, APRF, HIES.

GPX7 is a member of the glutathione peroxidase family. Glutathione peroxidases (GPx) are a family of enzymes with peroxidase activity whose central biological role is to guard the organism from oxidative damage by reducing lipid hydroperoxides to their corresponding alcohols and to reduce free hydrogen peroxide to water.

L-Asparaginase is an enzyme that depletes L-Asparagine "an important nutrient for cancer cells" resulting in cancer/tumor cell starvation. L-asparaginase is an anti-tumor agent derived from E.coli.,which can inhibit the growth of malignant cells. It is used mainly for the induction of remission in acute lymphoblastic leukaemia. Because of the lymph node origin of malignant B cells in Multiple Myeloma, L-Asparagine is an essential amino acid for their cell metabolism, and, consequently, L-Asparaginase may be of value in managing the disease.
The rationale behind asparaginase is that it takes advantage of the fact that ALL cellsare unable to synthesize the non-essential amino acidasparaginewhereas normal cells are able to make their own asparagine. These leukemic cells depend on circulating asparagine. Asparaginase however catalyzes the conversion of L-asparagine to aspartic acidand ammonia. This deprives the leukemic cell of circulating asparagine.

PRPS1 catalyzes the synthesis of phosphoribosylpyrophosphate (PRPP) that is essential for nucleotide synthesis. PRPS1 catalyzes the phosphoribosylation of ribose 5-phosphate to 5-phosphoribosyl-1-pyrophosphate, which is essential for purine metabolism and nucleotide biosynthesis. Defects in PRPS1 result in phosphoribosylpyrophosphate synthetase superactivity, Charcot-Marie-Tooth disease X-linked recessive type 5 and Arts Syndrome.

The epidermal growth factor receptor (EGF R) subfamily of receptor tyrosine kinases comprises four members: EGF R (also known as HER1, ErbB1 or ErbB), ErbB2 (Neu, HER-2), ErbB3 (HER-3), and ErbB4 (HER-4). All family members are type I transmembrane glycoprotein that has an extracellular domain which contains two cysteine-rich domains separated by a spacer region that is involved in ligand-binding, and a cytoplasmic domain which has a membrane-proximal tyrosine kinase domain and a C-terminal tail with multiple tyrosine autophosphorylation sites. The human EGF R gene encodes a 1210 amino acid (aa) residue precursor with a 24 aa putative signal peptide, a 621 aa extracellular domain, a 23 aa transmembrane domain, and a 542 aa cytoplasmic domain. EGF R has been shown to bind a subset of the EGF family ligands, including EGF, amphiregulin, TGFa , betacellulin, epiregulin, heparin-binding EGF and neuregulin-2 in the absence of a co-receptor. Ligand binding induces EGF R homodimerization as well as heterdimerization with ErbB2, resulting in kinase activation, tyrosine phosphorylation and cell signaling. EGF R can also be recruited to form heterodimers with the ligand-activated ErbB3 or ErbB4. EGF R signaling has been shown to regulate multiple biological functions including cell proliferation, differentiation, motility and apoptosis. In addition, EGF R signaling has also been shown to play a role in carcinogenesis.

PGAM1 is part of the phosphoglycerate mutase family. PGAM1 is an essential component of glucose and 2,3-BPGA (2,3-bisphosphoglycerate) metabolism and catalyzes the reversible reaction of 3-phosphoglycerate (3-PGA) to 2-phosphoglycerate (2-PGA) in the glycolytic pathway. PGAM1 is a dimeric enzyme containing, in different tissues, different proportions of a slow-migrating muscle (MM) isozyme, a fast-migrating brain (BB) isozyme, and a hybrid form (MB). PGAM1 mutations lead to muscle phosphoglycerate mutase deficiency, a.k.a. glycogen storage disease X.

GLIPR2 is linked to plant pathogenesis-related (PR-1) proteins, which are upregulated in reaction to pathogen attack. GLIPR2 is localized within lipid-enriched microdomains on the cytosolic side of the endomembrane system. GLIPR2 is closely attached to membranes and lacks the cytosol, though it lacks a membrane-spanning domain.

Ubiquitin-conjugating enzyme E2S (UBE2S) belongs to the ubiquitin-conjugating enzyme family. UBE2S is able to form a thiol ester linkage with ubiquitin in a ubiquitin activating enzyme-dependent manner, a typical property of ubiquitin carrier proteins. UBE2S catalyzes the covalent attachment of ubiquitin to other proteins. UBE2S acts as a crucial factor of the anaphase promoting complex/cyclosome (APC/C), which is a cell cycle-regulated ubiquitin ligase that controls progression through mitosis. UBE2S acts by purposely elongating 'Lys-11'-linked polyubiquitin chains initiated by the E2 enzyme UBE2C/UBCH10 on APC/C substrates, augmenting the degradation of APC/C substrates by the proteasome and promoting mitotic exit. UBE2S also acts by elongating ubiquitin chains initiated by the E2 enzyme UBE2D1/UBCH5 in vitro; it is nevertheless uncertain whether UBE2D1/UBCH5 acts as an E2 enzyme for the APC/C in vivo. UBE2S is also involved in ubiquitination and consequent degradation of VHL, resulting in an accumulation of HIF1A.

Gltathione S-transferase PI 2, also known as GSTP2 is multifunctional enzyme which is involved in theprotection of cellular components against anti-cancer drugs or peroxidative stress. Furthermore, down regulation of GSTP2induces an increase of oxidative damage in the pyramidal cells of the CA1&CA3 regions as well as in the granular layer ofthe dentate gyrus, which at the end leads to structural and functional damage.

UBE2E3 or Ubiquitin-conjugating enzyme E2 E3 is part of the E2 ubiquitinconjugating enzyme family. UBE2E3 is needed for the destruction of mitotic cyclins and for cell cycle progression. The ubiquitination process covalently attaches to a short protein of 76 amino acids called ubiquitin, to a lysine residue on the target protein. When a protein has been tagged with one ubiquitin molecule, other rounds of ubiquitination form a polyubiquitin chain that is recognized by the proteasome's 19S regulatory particle, triggering the ATP-dependent unfolding of the target protein which grants passage into the proteasome's 20S core particle, where proteases degrade the target into short peptide fragments for recycling by the cell.

GSTM3 belongs to the glutathione s-transferase (GST) family of proteins. There are eight GST proteins families, named alpha, kappa, mu, omega, pi, sigma, theta and zeta. Each one of the GST families has several proteins with different functions throughout the cell. The mu type of enzymes takes part in the detoxification of electrophilic compounds, including therapeutic drugs, carcinogens, environmental toxins and products of oxidative stress, by conjugation with glutathione.

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.

Beta-1,3-N-Acetylglucosaminyltransferase 2 (B3GNT2) is a part of the beta-1,3-N-acetylglucosaminyltransferase family which takes part in the synthesis of poly-N-acetyllactosamine. B3GNT2 is a type II transmembrane protein which prefers the substrate of lacto-N-neotetraose. B3GNT2 catalyzes the initiation and elongation of poly-N-acetyllactosamine chains and comprises the main polylactosamine synthase.

NADH dehydrogenase [ubiquinone] 1 alpha subcomplex assembly factor 4 (NDUFAF4) is involved in the compilation of mitochondrial NADH: ubiquinone oxidoreductase complex (complex I). In addition, NDUFAF4 is involved in cell proliferation and survival of hormone-dependent tumor cells. NDUFAF4 may also be a regulator of breast tumor cell invasion. NDUFAF4 gene mutations cause the mitochondrial complex I deficiency.