Large scale validation of human N-myc downstream-regulated gene (NDRG)-1 expression in endometrium during the menstrual cycle.
A major challenge in the comprehension of the endometrial transformations leading to the completion of each menstrual cycle in humans is in the identification of specific molecular pathways underlying these monthly turnovers. Towards this goal we compared, by the differential display technique, the relative expression of mRNA in endometrial biopsies harvested in individuals (n = 48) either at the proliferative or the secretory phase of the menstrual cycle. We isolated a cDNA fragment homologous to NDRG1 (N-myc Downstream-Regulated Gene-1) that is present in markedly higher amounts in the secretory phase. Northern blot analysis and quantitative real time PCR experiments confirmed this result in distinct cohorts of individuals (44 and 560 respectively). A closer examination of data showed that the highest mRNA levels were found during the range of 25-28 days of the uterine cycle. Consistent with the mRNA data, the temporal profile of the NDRG1 protein showed a 15-fold increase during the secretory phase, as demonstrated by using semi-quantitative dot blot analyses (n = 92). Immunohistochemical localization revealed that NDRG1 was expressed both in epithelial and stromal cells. This large scale validation of the NDRG1 mRNA and protein increase in endometrium during the secretory phase is consistent with its differentiation-related function described in other tissues and its potential involvement in the window of implantation of the human endometrium, as suggested by previous chip-based evidence.
Malette
B
B
MetrioGene Biosciences Inc., 6100 Royalmount Avenue, Montreal, Quebec, H4P 2R2, Canada.
Cherry
E
E
Lagacé
M
M
Bernard
M
M
Gosselin
D
D
Hugo
P
P
Shazand
K
K
D001483:Base Sequence; D015153:Blotting, Western; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002455:Cell Division; D016889:Endometrial Neoplasms / Q000737:chemistry / Q000235:genetics / Q000473:pathology; D004717:Endometrium / Q000166:cytology / Q000378:metabolism* / Q000473:pathology; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008597:Menstrual Cycle; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism; D016196:S Phase; D015398:Signal Transduction; D015854:Up-Regulation; D000099259:N-myc Downstream-Regulated Gene 1 Protein
D018797:Cell Cycle Proteins; D047908:Intracellular Signaling Peptides and Proteins; D012333:RNA, Messenger; D000099259:N-myc Downstream-Regulated Gene 1 Protein