CALB2
MIM.114051 16q22.1
Definition: Calbindin-2 (CALB2, calretinin) is a calcium-binding protein belonging to the troponin C superfamily (MIM.191040), close to the S-100 proteins (S100s).
Calretinin is a calcium-binding protein expressed in different normal and neoplastic tissues.
Expression in tissues
In normal tissues, a particularly strong expression was found in Leydig cells of the testis, neurons of the brain, theca-lutein and theca interna cells of the ovary, and mesothelium.
Expression in tumors
granular cell tumor (100%)
schwannoma (100%)
neurofibroma (7%)
malignant mesotheliomas
Leydig cell tumors of the testis
adenomas of adrenal gland
adenomatoid tumors
Early studies suggested that calretinin is a useful marker to differentiate adenocarcinomas from malignant mesotheliomas of the lung, but subsequent work has shown that calretinin can be expressed in several other tumor types.
In tumors, strong calretinin expression was most frequently found in malignant mesotheliomas, Leydig cell tumors of the testis, adenomas of adrenal gland, and adenomatoid tumors.
In summary, calretinin is frequently expressed in many different tumor types.
Metastases of various different origins must be included in the differential diagnosis of calretinin-positive pleura tumors.
subtypes of central and peripheral neurons
mast cells
Leydig cells of the testis
neurons of the brain
theca-lutein and theca interna cells of the ovary
mesothelium.
Pathology
loss of calretinin expression indicates aganglionosis in Hirschsprung’s disease (#15220363#)
References
Calretinin Staining Facilitates Differentiation of Olfactory Neuroblastoma From Other Small Round Blue Cell Tumors in the Sinonasal Tract. Wooff JC, Weinreb I, Perez-Ordonez B, Magee JF, Bullock MJ. Am J Surg Pathol. 2011 Oct 20. PMID: #22020045#
Kapur RP, Reed RC, Finn L, Patterson K, Johanson J, Rutledge JC. Calretinin immunohistochemistry versus acetylcholinesterase histochemistry in the evaluation of suction rectal biopsies for Hirschsprung disease. Pediatr Dev Pathol. 2008 Apr 28:1. PMID: #18442301#
Barshack I, Fridman E, Goldberg I, Chowers Y, Kopolovic J. The loss of calretinin expression indicates aganglionosis in Hirschsprung’s disease. J Clin Pathol. 2004 Jul;57(7):712-6. PMID: #15220363#
Calretinin expression in human normal and neoplastic tissues: a tissue microarray analysis on 5233 tissue samples. Lugli A, Forster Y, Haas P, Nocito A, Bucher C, Bissig H, Mirlacher M, Storz M, Mihatsch MJ, Sauter G. Hum Pathol. 2003 Oct;34(10):994-1000. PMID: #14608532#