Identification of Wnt family inhibitors: A pituitary tumor directed whole genome approach

Department of Endocrinology, Waikato Hospital, Private Bag 3200, Hamilton 3240, Waikato, New Zealand.
Molecular and Cellular Endocrinology (Impact Factor: 4.41). 03/2010; 326(1-2):48-54. DOI: 10.1016/j.mce.2010.02.039
Source: PubMed


Wnt signaling pathways are important regulators of normal embryological development including that of the pituitary gland. Altered Wnt pathway expression is common in many human tumors however until recently the role of these pathways in human pituitary tumorigenesis has received little attention. The advent of microarray analysis has identified several Wnt pathway inhibitors that are frequently perturbed in pituitary tumors. In this review we summarize the role of these inhibitors in other human tumor types and review the current state of knowledge of Wnt inhibitor expression in pituitary tumors.

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    • "Giles et al. showed that Wnt4 is expressed in the adult pituitary gland and that its expression is increased by estrogen exposure, suggesting that adult tissue plasticity is likely to involve í µí»½-catenin-independent signaling pathways, and conclusively showed Wnt signaling in estrogen-induced lactotroph proliferation [37]. A review of 13 whole genome approaches in pituitary tumors with the goal of identifying Wnt family inhibitors showed that expression of WF1, SFRP2, FRZB, SFRP4, DKK2, and SOSTDC1 genes is decreased in pituitary adenomas compared to normal pituitary tissue, while that of SFRP1 and SFRP4 is increased [38]. "
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