Cancer

MMP24 is an extracellular matrix (ECM) degradative peptidase enzyme that is a member of the large family of matrix metalloproteinases (MMP). Each MMP has a different substrate specificity, and the aberrant or derailed expression of these is strongly correlated with unregulated events such as tumor invasion, metastasis, angiogenesis, and arthritis. This is in contrast to the tightly controlled normal physiological processes such as tissue remodeling, reproduction, rebuilding, and embryonic development. Deregulation often occurs through the loss of negative checks.

GPNMB is a type I transmembrane glycoprotein with homology to the PMEL17 precursor, a melanocyte-specific protein. Two transcript variants encoding different isoforms exist.GPNMB is expressed in minimally (but not highly) metastatic human melanoma cell lines and xenografts and may be involved in the delay and reduction of metastatic potential and growth.

What is Ly6G?

The BAG proteins are a large family of chaperone regulators governing a wide range of cell processes such as proliferation, survival, stress response, tumorigenesis, neuronal differentiation, growth arrest and apoptosis as reviewed in Takayama et al¹. BAG proteins are co-chaperones that interact with several forms of the chaperone heat shock protein 70 (Hsp70) – the association allows them to both positively and negatively regulate Hsp70.

Factor VII (coagulation factor VII) is a 50 kD multidomain single chain plasma glycoprotein synthesized in the liver. It is a vitamin K-dependent serine protease essential for the extrinsic pathway of hemostasis, or blood coagulation. Factor VII circulates in the blood in a zymogen form that is converted to an active form (via factor IXa, factor Xa, factor XIIa, or thrombin).

The type I transmembrane glycoprotein EpCAM is a monomeric membrane glycoprotein that is expressed on most epithelial cell membranes as well as on a variety of epithelial carcinomas. It contains an extracellular domain with two epidermal growth factor-like extracellular domain repeats adjacent to a cysteine-poor region, along with a transmembrane domain, and a short cytoplasmic tail. EpCAM is a powerful tool for the detection of circulating and disseminated cancer cells (CTCs/DTCs) in blood and bone marrow, and it is the most commonly used epithelial marker to capture CTCs/DTCs.

CD38 is a 42 kD type II transmembrane glycoprotein that uses nicotinamide adenine dinucleotide (NAD) as a substrate to form cyclic adenosine diphosphate ribose (cADPR). This novel multifunctional ectoenzyme has both cyclase and hydrolase enzymatic activity, and is expressed on the surface of most white blood cells (CD4+, CD8+, B-lymphocytes and natural killer (NK) cells).  It is also expressed at high levels in normal tissues and organs like the pancreas, liver, and kidney as well as in malignant lymphoma and neuroblastoma.

Keratins, also called cytokeratins, are a family of filamentous structural proteins that form the intermediate filaments within epithelial cells. Keratins are differentially expressed depending on both the epithelial cell origin and degree of differentiation. An antibody to any given keratin is useful either as a stand-alone or part of an antibody panel to help identify or clarify tissue origin. Cytokeratin 18 (CK18) is a 45 kD normal constituent of the hepatocyte cytoskeleton and is expressed in combination with cytokeratin 8.

The Ki67 antigen is a prototypic cell cycle-related protein expressed by proliferating cells in all phases of the active cell cycle (G1, S, G2 and M). It is a non-histone nuclear protein originally identified in a Hodgkin's lymphoma-derived cell line. Ki67 interacts with KIF15 and MKI67IP, and is approximately 395 kD. It exhibits a complex nuclear localization pattern that is cell cycle-dependent - expression peaks during late G1, S, G2, and M phases, but is undetectable in G0.

Podoplanin is a mucin-type 1 transmembrane glycoprotein found in a wide range of tissues. It appears to be differentially expressed in endothelial cells of lymphatic but not blood vessel origin. In normal skin and kidney, podoplanin co-localizes with VEGFR3/FLT4, another marker for lymphatic endothelial cells. It appears to be involved in lymphangioigenesis and cell migration and is regulated by the lymphatic-specific homeobox gene Prox1. Podoplanin has also been found to be expressed on a wide variety of tumors.