The beta form of the estrogen receptor is predominantly expressed in the papillary cystic neoplasm of the pancreas.
BACKGROUND
Papillary cystic neoplasm (PCN) of the pancreas is a low-malignancy tumor affecting predominantly young females. Sex steroid hormones have been involved in its development and/or growth. Estrogen receptor (ER) has been scarcely found in this tumor, although there is some evidence suggesting expression of the beta-isoform. Unlike ER, progesterone receptor (PR) expression has been consistently observed. Immunohistochemical analysis of the two isoforms of ER has not been performed in this tumor.


OBJECTIVE
To characterize expression of ER isoforms with an immunohistochemical method.


METHODS
Expression of ER-alpha, ER-beta, and PR was analyzed by immunohistochemistry using isoform-specific ER and PR antibodies in paraffin-embedded tissue blocks from seven cases of PCN of the pancreas.


RESULTS
Most patients were young females. ER-alpha and ER-beta were present in two and six tumors, respectively. PR was identified in six tumors.


CONCLUSIONS
ER-beta expression predominates over the alpha-isoform in PCN of the pancreas. This finding supports the idea that previous negative results on ER expression were a consequence of the use of antibodies with no anti-beta activity. The role of ER-beta in the milieu of factors promoting the development and aggressiveness of PCN needs to be elucidated to address novel diagnostic and therapeutic approaches.
Morales
Angélica
A
Department of Reproductive Biology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, México City, México.
Duarte-Rojo
Andrés
A
Angeles-Angeles
Arturo
A
Mery
Carlos M
CM
Ruíz-Molina
Juan M
JM
Díaz-Sánchez
Vicente
V
Robles-Díaz
Guillermo
G
D000293:Adolescent; D000328:Adult; D000368:Aged; D002291:Carcinoma, Papillary / Q000378:metabolism* / Q000473:pathology; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D010190:Pancreatic Neoplasms / Q000378:metabolism* / Q000473:pathology; D011960:Receptors, Estrogen / Q000276:immunology / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000276:immunology / Q000378:metabolism
D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone