Endocrine Abstracts

One third of pituitary adenomas surgically removed are invasive, the presence of which increases the patients' risk of morbidity and mortality. IL6 has been shown to have conflicting effects on growth of human pituitary adenoma cells in culture but may act not only with mitogenic effects but on facilitating tumour invasion into surrounding tissue. We have previously shown IL6 mRNA expression correlates with invasive status and tumour volume(1). IL6 and IL1 are known to stimula...

There is increasing evidence that cytokines may play an important role in the pathogenesis of human pituitary adenomas. We have measured the production of interleukin-1 alpha from 30 cultured human pituitary adenomas and looked at the relationship of its secretion to interleukin-6 and soluble gp130. Tumours were also analysed for interleukin-2 secretion. We also used the HP75 cell line to look at the effects of varying levels of interleukin-1 on interleukin-6 secretion.<p...

Leptin is known to be produced by human pituitary adenomas, and inhibits the proliferation of HP75 cells in vitro. The HP75 cell line is derived from gonadotroph tumour cells from a clinically non-functioning human pituitary adenoma transfected with SV40. The aim of this study was to examine the effects of interleukins (IL) IL1-alpha and IL-6 on growth of HP75 cells and their effects on the growth inhibitory actions of leptin.HP75 cells were plated in 2...

Tyrosine kinase inhibitors have previously been shown to inhibit DNA synthesis in human pituitary adenomas (Jones et al JCEM 1997; 82: 2143-7). ZD1839 ('Iressa'), a selective inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase, is currently undergoing clinical trials in human cancers. We have investigated the effects of ZD1839 and EGF in the human pituitary cell line HP75 (derived by SV40 transfection of a human pituitary silent gonadotrophinoma) and in s...

The cytokine IL-6 is synthesed and released by over half of surgically removed human pituitary adenomas and by the HP75 human pituitary tumour cell line. We have previously shown that IL6 is associated with tumour invasiveness but not with Ki67, a marker of cell proliferation. Membrane IL6R (mIL6R) has been demonstrated in some pituitary adenomas, however, we have shown that sIL6R is not shed by the majority (92%) of human pituitary adenomas in culture nor by HP75 cells(super)...