| Clone | QR009 |
|---|---|
| REF | C-P005 |
| Dilution | 1:20 |
| Immunogen | Synthetic peptide of human PMS2 |
| Isotype | IgG |
| Species of origin | Rabbit |
DNA mismatch repair (MMR) system consists of four major proteins called MLH1, MSH2, MSH6, and PMS2. These proteins work two by two, MLH1 with PMS2 and MSH2 with MSH6. Loss of function of one of the four proteins leads to inactivation of the MMR system, resulting in a loss of fidelity of the replication and an accumulation of mutations thereby leading to microsatellite instability (MSI). MSI is associated with hereditary nonpolyposis colorectal cancer (HNPCC, Lynch syndrome), which is characterized by the development of colorectal cancer, endometrial cancer and various other tumors at early age.
Loss of PMS2 function due to gene mutation or epigenetic changes is characterized by absence of nuclear expression in neoplastic cells, whereas intact nuclear PMS2 expression indicates normal PMS2 function and no gene mutations. PMS2 is normally expressed in most cases of sporadic colorectal cancer (CRC). Isolated loss of PMS2 staining is an uncommon immunophenotype among CRCs, accounting for approximately 4%. Anti-PMS2 is useful in detection of MSI, especially in a panel with MSH2 (QR010), MSH6 (QR011) and MLH1 (QM003).
