MCM5 (MSVA-505R)
Recombinant Rabbit monoclonal / IgG 1:50 – 1:100 Research Use Only Intracellular Human MSVA-505R Minichromosome maintenance complex component 5, CDC46, MGORS8, P1-CDC46 Colon: A strong nuclear MCM5 immunostaining should be seen in virtually all crypt base cells. Colon: MCM5 immunostaining should be less intense or absent in surface epithelial cells and absent in most stroma cells. MCM5 is a highly sensitive marker for proliferating cells. The MCM5 gene is located at 22q12.3 and codes for a nuclear protein which belongs to the highly conserved mini-chromosome maintenance proteins (MCM) 2-7 that play a key role in genome replication. They form a ring-shaped hexameric protein complex which unwinds double-stranded DNA, forms a replication fork during the initiation of DNA replication, and helps to recruit other DNA replication related proteins. The MCM2-7 limits DNA replication to a single occurrence per cell division and is critical for maintaining genome integrity. The MCM proteins are expressed in all cells in the G1, S, G2 and M-phase of the cell cycle but in contrast to the better established proliferation marker Ki-67, MCMs are already expressed in early G1 phase. This results in the detection of more proliferating cells as compared to Ki67 immunohistochemistry which might be advantageous in tumor types with low proliferative activity. Whether the role of MCM5 specifically differs from those of other MCM proteins is n... Images describing the MCM5 staining pattern in normal tissues obtained by the antibody MSVA-505R are shown in our “ Normal Tissue Gallery ”. Brain Cerebrum Negative. Cerebellum Negative. Endocrine Tissues Thyroid Weak to moderate nuclear MCM5 staining of a small fraction of follicular cells. Parathyroid Distinct nuclear MCM5 staining in a very small fraction of epithelial cells. Adrenal gland A variable MCM5 staining occurs in a small fraction of adrenocortical cells. Spindle shaped nuclei are also found positive. Pituitary gland Negative. Respiratory system Respiratory epithelium Significant MCM5 staining in a fraction of (mostly basal/suprabasal) respiratory epithelial cells. Lung Distinct MCM5 staining of a subset of pneumocytes. Gastrointestinal Tract Salivary glands Distinct MCM5 staining in a fraction of epithelial cells. Esophagus Distinct MCM5 staining of suprabasal and (much less intense) basal cells of the squamous epithelium. Stomach Strong nuclear MCM5 immunostaining of man... A nuclear MCM5 immunostaining in a fraction of tumor cells is always seen in cancerous tissues. The TCGA findings on MCM5 RNA expression in different tumor categories have been summarized in the Human Protein Atlas. Colorectal adenocarcinoma with strong
MCM5 positivity of a large fraction of
tumor cells. Non-invasive urothelial carcinoma (low
grade, pTaG2) with distinct MCM5
staining of few tumor cells. Ovarian serous high-grade carcinoma
with strong nuclear MCM5 staining of
>90 of tumor cells. Cancer tissue gallery No data available at the moment IHC users have different preferences on how the stains should look like. Some prefer high staining intensity of the target stain and even accept some background. Others favor absolute specificity and lighter target stains. Factors that invariably lead to more intense staining include higher concentration of the antibody and visualization tools, longer incubation time, higher temperature during incubation, higher temperature and longer duration of the heat induced epitope retrieval (slide pretreatment). The impact of the pH during slide pretreatment has variable effects and depends on the antibody and the target protein. All images and data shown here and in our image galleries are obtained by the manual protocol described below. Other protocols resulting in equivalent staining are described as well. Manual protocol Freshly cut sections should be used (less than 10 days between cutting and staining). Heat-induced antigen retrieval for 5 minutes in an autoclave at 121°C in pH 7,8 Target ... The prognostic role of the percentage of MCM5 positive cells is yet unknown. It is unclear whether MCM5 quantification is equally or better suited than the established Ki67-Li for prognosis assessment in tumors with rather low proliferation rate. In principle, there are two ways how the specificity of antibodies can be documented for immunohistochemistry on formalin fixed tissues. These are: 1. Comparison with a second independent method for target expression measurement across a large number of different tissue types (orthogonal strategy), and 2. Comparison with one or several independent antibodies for the same target and showing that all positive staining results are also seen with other antibodies for the same target (independent antibody strategy). Orthogonal validation: For the antibody MSVA-505R , specificity of staining is in line with data from three independent RNA screening studies, including the Human Protein Atlas (HPA) RNA-seq tissue dataset, the FANTOM5 project, and the Genotype-Tissue Expression (GTEx) project, which are all compiled in the Human Protein Atlas (Tissue expression MCM5) . In agreement with MSVA-505R immunostaining data, MCM5 RNA expression is highest in lymphatic and hematopoetic tissues but occur...
