Research is focused on the long term morbidity associated with polycystic ovary syndrome (PCOS). The results have shown: Cardiovascular Disease Significant abnormalities in haemodynamics and arterial mechanical properties in vivo which precede cardiovascular disease. A rat model has also been established, in which vascular characteristics have been investigated in vivo and in vitro. Endometrial Cancer The results of a prevalence study of PCO in patients with endometrial cancer have challenged the association between the two conditions. Expression of cell cycle and apoptotic proteins has also challenged the assumption that the prognosis for women with this tumour is improved if they have PCOS. Endometrial samples are being analysed using microarray analysis to identify the subset of PCOS women at greatest risk of developing endometrial cancer. Using differential display, we have assessed gene expression in the ovaries of women with PCOS and healthy controls. Numerous putative differentially expressed genes have been found and the first of these (?2 smooth muscle actin) has been confirmed to be differentially expressed at the gene and protein level. A project is underway in the TRL to establish an immortalized endometrial cell line which will be used to assess the effects of the endocrine and metabolic environment in PCOS in relation to carcinogenesis and early pregnancy loss.