Differential expression of somatostatin receptors in medulloblastoma.
OBJECTIVE
Somatostatin receptors have been found on a variety of tumours like neuroendocrine breast or brain tumours. Their detection opens new diagnostic and therapeutic paths. The aim of this work was to investigate their expression in medulloblastomas.


METHODS
Using both techniques, reverse transcriptase-polymerase chain reaction and immunohistochemistry, we analysed mRNA of different subtypes of somatostatin receptors in 15 medulloblastomas and the localisation of the subtype SSTR2 receptor at the cellular level in 13 medulloblastomas. All five subtypes mRNA were variably expressed in each medulloblastoma. The signal obtained after Southern blotting for SSTR2 receptor amplification was the highest as compared to the signal obtained for the other receptor subtypes. Immunostaining for SSTR2A receptor was present in every tumour specimen and was specifically located to the cellular membrane of neoplastic cells. No staining was identified at the level of peritumoral veins.


CONCLUSIONS
The evidence of predominant expression of SSTR2 receptors in medulloblastomas opens interesting prospects for their diagnosis and therapy.
Guyotat
J
J
Service de Neurochirurgie B, Hĵpital Neurologique et Neurochirurgical Pierre Wertheimer, Lyon, France.
Champier
J
J
Pierre
G S
GS
Jouvet
A
A
Bret
P
P
Brisson
C
C
Belin
M F
MF
Signorelli
F
F
Montange
M F
MF
D002528:Cerebellar Neoplasms / Q000235:genetics* / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008527:Medulloblastoma / Q000235:genetics* / Q000473:pathology*; D008565:Membrane Proteins; D012333:RNA, Messenger / Q000032:analysis; D017481:Receptors, Somatostatin / Q000032:analysis* / Q000235:genetics*
D008565:Membrane Proteins; D012333:RNA, Messenger; D017481:Receptors, Somatostatin; C103631:somatostatin receptor 3; C098681:somatostatin receptor subtype-4; C101130:somatostatin receptor type 1; C094573:somatostatin receptor 5; C093733:somatostatin receptor 2