Expression of menin gene mRNA in pituitary tumours.
OBJECTIVE
Multiple endocrine neoplasia type 1 (MEN 1) is an autosomal dominant inherited disorder characterised by the combined occurrence of parathyroid, endocrine pancreas and anterior pituitary tumours. The gene responsible for MEN 1, the menin gene, a putative tumour-suppressor gene located on human chromosome 11q13, has been cloned. To investigate the role of the menin gene in sporadic anterior pituitary tumorigenesis, its mRNA was assessed in a group of pituitary tumours.


METHODS
Menin gene expression, along with glyceraldehyde phosphate dehydrogenase (GAPDH) gene expression, has been studied in a group of normal pituitaries and in 23 pituitary tumours not associated with the MEN 1 syndrome. The pituitary tumours included 4 prolactinomas, 11 growth-hormone-secreting tumours and 8 non-functional tumours. Total RNA was extracted from the normal pituitaries and tumours, and cDNA was synthesised with standard reverse transcriptase methods. Duplex polymerase chain reaction (PCR) was standardised in order to quantify the expression of the menin gene using intron-spanning primers across exons 9 and 10 in relation to the 'house-keeping' gene GAPDH. The PCR products were separated on agarose gel and densitometric analysis of the bands allowed semi-quantification.


RESULTS
There was no evidence for a change in menin gene expression in any of the pituitary tumours when compared with normal pituitaries.


CONCLUSIONS
These studies complement previous work on mutational analysis, and do not suggest a major role for the menin suppressor gene in sporadic pituitary tumorigenesis.
Satta
M A
MA
Department of Endocrinology, St Bartholomew's Hospital, London EC1A 7BE, UK.
Korbonits
M
M
Jacobs
R A
RA
Bolden-Dwinfour
D A
DA
Kaltsas
G A
GA
Vangeli
V
V
Adams
E
E
Fahlbusch
R
R
Grossman
A B
AB
D017931:DNA Primers; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D018761:Multiple Endocrine Neoplasia Type 1 / Q000235:genetics / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D010911:Pituitary Neoplasms / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D017931:DNA Primers; C105373:MEN1 protein, human; D009363:Neoplasm Proteins; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases