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Chromogranin A is a 439 amino acid protein which is encoded on chromosome 14 and is present in neuroendocrine cells throughout the body, including the neuroendocrine cells of the large and small intestine, adrenal medulla and pancreatic islets. It is an excellent marker for carcinoid tumors, phenochromocytomas, paragangliomas, and other neuroendocrine tumors.
Coexpression of chromogranin A and neuron specific enolase (NSE) is common in neuroendocrine neoplasms.

WHSC2 (NELF-A) is a protein factor required for DRB-sensitive transcription. WHSC2 is one of the 5 components of the multisubunit NELF complex which cooperates with DSIF to repress RNA polymerase II elongation. The Wolf-Hirschhorn syndrome is a multiple malformation syndrome characterized by mental and developmental defects resulting from a hemizygous deletion of the distal short arm of chromosome 4 (4p16.3).

AHSG (fetuin-A) which is a glycoprotein present in the serum, is synthesized by hepatocytes. AHSG is one of the fetuin class of plasma binding proteins. It is involved in a number of functions, such as endocytosis, brain development and the formation of bone tissue. It is usually present in the cortical plate of the immature cerebral cortex and bone marrow hemopoietic matrix, hence it has been postulated that it participates in the development of the tissues. Yet, its exact significance is still vague. AHSG promotes endocytosis, hold opsonic properties and influences the mineral phase of the bone. Affinity for calcium and barium ions has been shown.

Tachykinin-1 (TAC1) belongs to the tachykinin peptide hormone family. TAC1 are a family of peptides which have similar biologic activities and share a common C-terminal sequence, phe-X-gly-leu-met-NH2, however they have distinct N-terminal sequences that convey receptor specificities. TAC1 is assumed to act as neurotransmitters which interact with nerve receptors and smooth muscle cells. TAC1 induces behavioral responses and serves as vasodilators and secretagogues.

THAP Domain Containing, Apoptosis Associated Protein 7 (THAP7) holds one THAP-type zinc finger. THAP7 is a chromatin-associated, histone tail-binding protein which represses transcription by recruiting HDAC3 and nuclear hormone receptor corepressors.

CTK-19 is a member of the keratin family. The keratins are intermediate filament proteins responsible for the structural integrity of epithelial cells and are subdivided into cytokeratins and hair keratins. The type I cytokeratins consist of acidic proteins which are arranged in pairs of heterotypic keratin chains. Unlike its related family members, this smallest known acidic cytokeratin is not paired with a basic cytokeratin in epithelial cells. It is specifically expressed in the periderm, the transiently superficial layer that envelopes the developing epidermis. The type I cytokeratins are clustered in a region of chromosome 17q12-q21.

E-cadherin (uvomorulin, cell-CAM120/80) is a calcium dependent cell adhesion molecule expressed predominately in epithelial tissues. It plays an important role in the growth and development of cells via the mechanisms of control of tissue architecture and the maintenance of tissue integrity. Numerous studies have demonstrated that reduction and/or loss of Ecadherin expression in carcinomas correlates positively with the potential of these tumors for invasion and metastasis.

Serine/threonine/tyrosine-interacting protein (STYX) is a member of the protein-tyrosine phosphatase family. STYX contains a Gly residue instead of a conserved Cys residue in the dsPTPase catalytic loop which makes it catalytically inactive as a phosphatase. On the other hand, the binding pocket is adequately preserved to bind phosphorylated substrates, and may protect them from phosphatases. STYX may have a role in spermiogenesis. STYX is a possible pseudophosphatase.

Transcription Factor 4 (TCF4) acts as a transcription factor and takes part in the initiation of neuronal differentiation. TCF4 recognizes an Ephrussi-box ('E-box') binding site ('CANNTG') - a motif primary identified in immunoglobulin enhancers. TCF4 is mainly expressed in pre-B-cells, even though it is present in other tissues as well.

TIMP2 belongs to the TIMP gene family. The proteins encoded by this gene family are natural inhibitors of the matrix metalloproteinases, a group of peptidases that take part in degradation of the extracellular matrix. Besides having an inhibitory role against metalloproteinases, the encoded protein has a exclusive part among TIMPfamily members in its capability to directly suppress the proliferation of endothelial cells. Consequently, the encoded protein is crucial to the conservation of tissue homeostasis by suppressing the production of quiescent tissues as an answer to angiogenic factors, and by inhibiting protease activity in tissues undergoing renovation of the extracellular matrix.

FSTL1 protein resembles follistatin, an activin-binding protein. FSTL1 is an autoantigen associated with rheumatoid arthritis and it holds an FS section, a follistatin-like sequence having 10 conserved cysteine residues.

FtsJ RNA Methyltransferase Homolog 2 (FTSJ2) belongs to the S-adenosylmethionine-binding protein family. FTSJ2 is a nucleolar protein and which is involved in cell cycle control and DNA repair and the processing and modification of rRNA. FTSJ2 is extensively expressed, with the highest expression in the muscle, placenta, and heart.

GH is a member of the somatotropin/prolactin family of hormones which play an important role in growth control. The gene, along with four other related genes, is located at the growth hormone locus on chromosome 17 where they are interspersed in the same transcriptional orientation; an arrangement which is thought to have evolved by a series of gene duplications. The five genes share a remarkably high degree of sequence identity. Alternative splicing generates additional isoforms of each of the five growth hormones, leading to further diversity and potential for specialization. This particular family member is expressed in the pituitary but not in placental tissue as is the case for the other four genes in the growth hormone locus. Mutations in or deletions of the gene lead to growth hormone deficiency and short stature.

MAPT is a neuronal microtubule associated protein localized mostly on axons.
MAPT promotes tubulin polymerisation and stabilizes microtubules, however it also serves to connect certain signalling pathways to the cytoskeleton. MAPT, in its hyperphosphorylated form, is the main part of paired helical filaments (PHF) and neurofibrillary lesions in Alzheimer''s disease (AD) brain.

Cystatin-A is the intracellular inhibitor of cysteine proteinase cathepsin B (CatB) and belongs to family 1 of the cystatin superfamily of inhibitor proteins. CSTA is a stefin that functions as a cysteine protease inhibitor, forming tight complexes with papain and the cathepsins B, H, and L. It has been proposed that extracellular CatB together with other classes of proteinases are all subjected to a cascade-like manner of activation. CatB and its inhibitor Cystatin-A are involved in degradation of extracellular matrix proteins during tissue remodeling. CSTA is one of the precursor proteins of cornified cell envelope in keratinocytes and plays a role in epidermal development and maintenance. Cystatin-A has been reported to be found in high concentrations in epithelial cells, polymorphonuclear leukocytes and lymphoid tissue. Stefins may be used as prognostic and diagnostic tools for cancer.

SAR1B is a small GTPase that functions as a homodimer. GTP-Binding Protein SAR1B (SAR1b) is involved in transport from the endoplasmic reticulum to the Golgi apparatus and also in the selection of the protein cargo and the assembly of the COPII coat complex. The SAR1B protein is activated by the guanine nucleotide exchange factor PREB. SAR1B gene defects are a cause of chylomicron retention disease (CMRD), also known as Anderson disease (ANDD).

Cathepsin-Z (CTSZ) is a lysosomal cysteine proteinase and member of the peptidase C1 family. CTSZ, which has been also known as cathepsin X and cathepsin P, exhibits carboxy-monopeptidase and carboxy-dipeptidase activities. CTSZ is expressed ubiquitously in cancer cell lines and primary tumors and, similar to other members of this family, takes part in tumorigenesis.

Cytohesin 1 also known as CYTH1 belongs to the PSCD family. CYTH1 is responsible for promoting guanine-nucleotide exchange on ARF1 and ARF5 and also promotes the activation of ARF factors by the replacement of GDP with GTP.

DHPS is vital for the first step of hypusine biosynthesis. DHPS catalyzes the NAD-dependent transfer of the butylamine moiety of spermidine to the epsilon-amino group of a specific lysine residue of the EIF5A precursor protein to form the intermediate deoxyhypusine residue.

Stratifin is part of the 14-3-3 family. The 14-3-3 family of proteins plays an important regulatory function in signal transduction, checkpoint control, apoptotic and nutrient-sensing pathways. 14-3-3 proteins are highly conserved and ubiquitously expressed. There are 7 isoforms, beta, gamma, epsilon, sigma, zeta, tau and eta that have been identified in mammals. Stratifin is an epithelial cell marker that functions as a tumor suppressor whose expression can be down regulated via methylation. Failure of Stratifin expression results in a defective G2/M phase checkpoint and results in epithelial and non-epithelial tumorigenesis.

TCEB1 (elongin C) is a subunit of elongin, which is a common transcription elongation factor that increases the RNA polymerase II transcription elongation past template encoded arresting sites. The SIII complex is comprised of elongins A/A2, B and C. The SIII complex activates elongation by RNA polymerase II by curbing transient pausing of the polymerase at numerous sites within transcription units. Elongin A acts as the transcriptionally active component of the SIII complex, while elongins B and C are regulatory subunits. Elongin A2 is specifically expressed in the testis, and able to forming a stable complex with elongins B and C. The VHL (von Hippel-Lindau) tumor suppressor protein binds to elongins B and C, and thus inhibits transcription elongation.

Celiac disease is an enteropathy that is characterized by intestinal lesions of variable severity. Tissue-type transglutaminase (tTG) is believed to be the predominant autoantigen for celiac disease and the corresponding autoantibodies show higher sensitivity and specificity than anti-gliadin antibodies. Highly pure recombinant human tTG is now available to replace the traditionally used tTG fraction from guinea pig.
Tissue-type transglutaminase antigens have been specifically modified for improved handling: exchange of an active site amino acid eliminates the protein cross-linking activity of the enzyme, while maintaining the native three-dimensional structure and the enzyme's secondary GTPase activity. This engineering assures reproducible properties of the antigen preparations through the absence of variable and ill-defined covalent aggregates of tTG antigen and host cell proteins.

PHPT1 is a member of the Janus protein familyand is 125 amino acid long. PHPT1 appears as a monomer in the cytoplasm and is an EDTA-insensitive phosphohistidine phosphatase. Overexpression of PHPT1 resolts in specific phosphohistidine phosphatase activity towards phosphopeptide I, with no activity detected towards phosphotyrosine, phosphothreonine and phosphoserine peptides.