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CD38 is a surface molecule which acts as a plasma membrane signaling receptor in leukocytes. Furthermore, CD38 functions as signaling channel which leads to to cellular activation and proliferation. CD38 also plays a role as an ectoenzyme with various functions as well as an inducer of Ca2+ mobilization from cytoplasmic stores. CD38 signals acts as a coreceptor on B cells and modulates B cell receptor.

Heterotrimeric guanine nucleotide-binding proteins (G proteins) which integrate signals between receptors and effector proteins, are comprised of an alpha, a beta and a gamma subunit. The alpha, beta and gamma subunits are encoded by families of related genes. GNB1 encodes a beta subunit. Beta subunits are vital regulators of alpha subunits, as well as of certain signal transduction receptors and effectors. G proteins are involved as a modulator or transducer in numerous transmembrane signaling systems. The beta and gamma chains are necessary for the GTPase activity, for replacement of GDP by GTP, and for G protein-effector interaction.

Rho-related GTP-binding protein RhoB (RhoB) belongs to the Rho GTP-binding protein family. RhoB facilitates apoptosis in neoplastically transformed cells after DNA damage. RhoB has a negative role in tumorigenesis since deletion causes tumor formation.

ATPase Transporting Lysosomal Accessory Protein 2 (ATP6AP2) is a protein associated with triphosphatases (ATPases). Proton-translocating ATPases have vital roles in energy conservation, secondary active transport, acidification of intracellular compartments, and cellular pH homeostasis. ATP6AP2 is linked with the transmembrane sector of the V-type ATPases, which have a transmembrane proton-conducting sector and an extramembrane catalytic sector. ATP6AP2 serves as a renin and prorenin cellular receptor; it mediates renin-dependent cellular responses by activating ERK1 and ERK2. ATP6AP2 is expressed in the brain, heart, placenta, liver, kidney and pancreas. ATP6AP2 is hardly detectable in the lung and skeletal muscles. ATP6AP2 is also expressed in the vascular structures and by syncytiotrophoblast cells in the mature fetal placenta.

Ras-related protein Ral-A (RALA) is a member of the small GTPase superfamily, Ras family of proteins. RALA mediates a distinct downstream signaling pathway from Ras which facilitates cellular transformation. Furthermore, RALA is thought to be involved in various signaling cascades, including regulation of the cytoskeleton, vesicle trafficking, and endocytosis.

Smac/Diablo is a proapoptotic protein that increases caspase activation in the cytochrome c/Apaf-1/caspase-9 pathway by its binding to the inhibitor of apoptosis proteins (IAPs) and removing their inhibitory activity. Smac/Diablo is a mitochondrial protein which enters the cytosol when cells go through apoptosis, and it moderates the caspase inhibition of IAPs.
Smac/DIABLO expression is associated with the result of renal cell carcinoma.
Dimeric form of Smac/DIABLO implies that once expressed in the cell the protein has a little probability of dissociation and, thus, loss of function.
Survivin, Smac/DIABLO, & PKC-? play an important part in the inhibition of apoptosis by FGF-2 in human small cell lung cancer cells. Mitochondrial survivin associates with Smac/DIABLO, delaying its release. Decreased expression of Smac protein takes part in ovarian carcinogenesis and chemotherapeutic resistance. Smac/DIABLO plays a role in tumor cells during the pathway of apoptosis induction. SMAC protein is regulated by XIAP and degraded by proteasome. SMAC protein takes part inleukemic cell apoptosis.
Smac is released during stress-induced apoptosis in multiple myeloma cells.

GNG4 belongs to a multigene family and is involved in defining the specificity of receptor-G protein interaction. In mammals, G protein alpha, beta and gamma polypeptides are encoded by no less than 16, 4 and 7 genes, respectively. It is a well-known fact that different G protein complexes expressed in different tissues carry structurally distinct members of the alpha beta and gamma subunits and that privileged connotation between members of subunit families rise G protein functional diversity.

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.

C1QTNF6 is a collagen type-IV specific for basement membranes. C1QTNF6 is vital for embryonic development.

NECTIN3, also known as Nectin Cell Adhesion Molecule 3, is part of the nectin family. NECTIN3 is intended to initiate cell-cell adhesion to stimulate cell attachment and to allow subsequent formation of JAM-and cadherin-based intercellular junctions. NECTIN3 induces endocytosis-mediated down-regulation of PVR from the cell surface, which results in reduction of cell movement & proliferation. Following Nectin-3 activity adds strength to the junction through trans-interaction with various molecules.

Receptor Transporter Protein 4 (RTP4) is a member of the TMEM7 family.

Growth hormone receptor, also known as GHR is part of the cytokine receptor family. GHR binds 2 receptor molecules and in this manner induces signal transduction through receptor dimerization. Furthermore, at high concentrations, growth hormone performs as an antagonist since there is a large difference in affinities at the respective binding sites. The antagonist action can be enhanced further by reducing binding in the low affinity binding site.

Mouse Lungkine/CXCL15 (WECHE) belongs to the ELR motif-containing CXC chemokines. The mouse Lungkine gene has been mapped to chromosome 5. The cDNA of mouse Lungkine encodes a 166 amino acids (aa) protein with a 25 aa predicted signal peptide and a 141 aa mature protein with an exceptionally long C-terminal tail which extends beyond beyond the chemokine fold. Lungkine protein is secreted into bronchoalveolar space and is involved in lung-specific neutrophils trafficking. Furthermore, studies in Lungkine knockout mice propose that Lungkine is an imperative mediator of neutrophil migration from the lung parenchyma into the airspace. In addition, Lungkine is chemotactic for bone marrow progenitor cells and modulates hematopoietic cell differentiation. By Northern blot analysis and in-situ hybridization, Lungkine transcripts have only been specifically detected in the adult and fetal lung, and its expression is up-regulated under inflammatory conditions. There is a 35% aa sequence similarity between the mouse Lungkine and the human ENA-78 and a 31% similarity with the human IL-8.

Ephrin-B2 belongs to the ephrin (EPH) family. The ephrins and EPH-related receptors contain the largest subfamily of receptor protein-tyrosine kinases and have been associated with mediating developmental events, particularly in the nervous system and in erythropoiesis. Based upon their structures and sequence relationships, ephrins are allocated into the ephrin-A (EFNA) class, which are anchored to the membrane by a glycosylphosphatidylinositol linkage, and the ephrin-B (EFNB) class, which are transmembrane proteins. Ephrin-B2 binds to the EPHB4 and EPHA3 receptors.

Protein Tyrosine Phosphatase 1B is the founding member of the protein tyrosine phosphatase (PTP) family, which was isolated and identified based on its enzymatic activity and amino acid sequence. PTPs catalyze the hydrolysis of the phosphate monoesters specifically on tyrosine residues. Members of the PTP family share a highly conserved catalytic motif, which is essential for the catalytic activity. PTPs are known to be signaling molecules that regulate a variety of cellular processes including cell growth, differentiation, mitotic cycle, and oncogenic transformation. This PTP has been shown to act as a negative regulator of INS signaling by dephosphorylating the phosphotryosine residues of INS receptor kinase. This PTP was also reported to dephosphorylate epidermal growth factor receptor kinase, as well as JAK2 and TYK2 kinases, which implicated the role of this PTP in cell growth control, and cell response to IFN stimulation.

Neuregulin/Heregulin is a family of structurally related polypeptide growth factors which are stemmed from alternatively spliced genes (NRG1, NRG2, NRG3 and NRG4). Thus far, there are more than 14 soluble and transmembrane proteins derived from the NRG1 gene. Proteolytic processing of the extracellular domain of the transmembrane NRG1 isoforms release soluble growth factors. HRG1-b1 is comprised of an Ig domain and an EGF-like domain which is necessary for direct binding to receptor tyrosine kinases erb3 and erb4. This binding stimulates erb3 and erb4 heterodimerization with erb2, promoting intrinsic kinase activity, which results in tyrosine phosphorylation. Even though HRG1-b1 biological effects are still unclear, it has been discovered to advance motility and invasiveness of breast cancer cells which in addition might entail up-regulation of expression and function of the autocrine motility-promoting factor (AMF).

Otubain 1 (OTUB1) belongs to the ovarian tumor (OUT) superfamily of predicted cysteine proteases and inhibits cytokine gene transcription in the immune system through its interaction with a ubiquitin protease and E3 ubiquitin ligase. OTUB1 is a highly specific ubiquitin iso-peptidase, it cleaves ubiquitin from branched poly-ubiquitin chains but not from ubiquitinated substrates. OTUB1 is believed to work in specific ubiquitin-dependent pathways, possibly by providing an editing function of polyubiquitin chain growth. OTUB1 is a hydrolase that removes conjugated ubiquitin from proteins in vitro and may therefore have a significant regulatory role in the level of protein turnover by preventing degradation. Additionally, OTUB1 is a regulator of T-cell anergy, a phenomenon that occurs when T-cells are rendered impassive to antigen re-challenge and no longer respond to their cognate antigen. OTUB1 acts via its interaction with RNF128/GRAIL, which is an essential inductor of CD4 T-cell anergy.

CD72 antigen is a member of the type II integral membrane glycoproteins which includes other related cell surface moleculaes such as the asialoglycoprotein receptors, CD23 and the Kupffer cell recpeotr. The exposure of B cells to CD72 antibodies activates a variety of signalling pathways and can induce MHC class II expression and B cell proliferation. CD72 antigen is expressed on all cells of B cell lineage with the exception of plasma cells and weakly on human tissue macrophages.

TNFAIP8 which is a part of the TNFAIP8 family acts as a negative mediator of apoptosis and takes part in tumor progression. TNFAIP8 suppresses the TNF-mediated apoptosis by inhibiting caspase-8 activity but not the processing of procaspase-8, resulting in inhibition of BID cleavage and activation of caspase-3.

PA2G4 belongs to the peptidase M24C family and functions as an RNA-binding protein involved in cellular proliferation and differentiation processes. PA2G4 is a component of pre-ribosomal ribonucleoprotein complexes, participating in ribosome assembly and regulating the later steps of rRNA processing. Also, PA2G4 interacts with ErbB-3 and may function as a modulator of the ErbB-3 mediated signal transduction pathway by regulating the effects of Neuregulin-1. Furthermore, PA2G4 is a transcriptional co-repressor of androgen receptor-regulated genes and other cell cycle regulatory genes through its interactions with histone deacetylases. PA2G4 is implicated in growth inhibition and the induction of differentiation of human cancer cells. In addition, PA2G4 mediates cap-independent translation of specific viral IRESs (internal ribosomal entry site). PA2G4 associates with 28S, 18S and 5.8S mature rRNAs, several rRNA precursors and probably U3 small nucleolar RNA.