Glucocorticoid Induced Leucine Zipper is a small leucine zipper protein of 17 kDa selleck catalog and a member of the TSC22D family of proteins also known as TSC22D3. GILZ was discovered as a dexamethasone induced tran script in murine thymocytes. Inhibitors,Modulators,Libraries It is widely expressed in immune tissues and has also been reported in epithelial tissues often associated to a hormonal background. It is rapidly induced by glucocorticoids in T lymphocytes, macrophages, dendritic cells and mast cells. GILZ expression in the anterior pituitary during embry onic development in the chick is consistent with regula tion by corticosteroids . in the kidney cortical collecting duct, GILZ is induced by aldosterone . and in human cervical adenocarcinoma HeLa cells, GILZ expression is controlled by estradiol.
GILZ interferes with Raf 1, nuclear factor kB, AP 1 and FoxO forkhead transcription factor FoxO3, all are key signaling molecules important for tumorigenesis. There have, however, been few studies of GILZ in cancer. GILZ has been reported in multiple myeloma, in lymphoblastic leukemia and in human oste osarcoma cells. Most relevant work has been in cell Inhibitors,Modulators,Libraries lines and very few data from human tumor specimens are available. To our knowledge, there is no report on GILZ in EOC. We therefore investigated GILZ expression and function in these malignant tumors. Inhibitors,Modulators,Libraries Our findings are supported by parallel and complementary data accumu lated in tumor specimens and in the BG 1 cellular model. We report evidence that GILZ, an intracellular factor not previously described in EOC, plays a pivotal role in tumor cell proliferation.
results GILZ detection in human ovarian tumor samples GILZ Inhibitors,Modulators,Libraries expression was assessed by immunohistochemical staining of sections isolated from three normal ovaries, seven benign EOC and 50 invasive EOC. GILZ was not detected on the surface epithelium of normal ovaries and in benign tumors. In contrast, among the invasive Inhibitors,Modulators,Libraries ovarian cancers, 40 expressed GILZ. GILZ immunoreactiv ity was detected in the four main histological subtypes, serous, clear cell, endometrioid and mucinous tumors. It was clearly confined to the cytoplasm of tumor cells and was weak in, or absent from the tumor stroma. Using the same antibody, we detected GILZ pro tein by western blot.
GILZ was revealed at 17 kDa, which is the size of the protein described by Ricardi and co work ers in 1997, in BG 1 cells transfected with the GILZ encoding vector pcDNA3 GILZ, in epithelial cells from malignant ascites and in ovarian tumor samples for which frozen tissues Belinostat were available, confirming the staining data. Interestingly, the non epithelial cells from malignant ascites do not express GILZ. GILZ 17 kDa protein was also detected in ovarian cancer cell lines SKOV 3, OVCAR 3 and BG 1. it was less abundant in BG 1 cell line than in SKOV 3 and OVCAR 3. BG 1 thus appeared as the best fitted cellular model for processing up and down regulation of GILZ.