BACKGROUND: @entity1968 and its natural and synthetic analogs ( @entity4878 ) affect a wide array of biological processes. @entity4878 are used in the treatment of many @entity272 and are promising drugs for several @entity5 . Most of their actions are thought to result from changes in gene expression which is done through nuclear @entity1968 receptors and retinoid X receptors. We conducted a study to determine whether the expression of these receptors is different in @entity5 and @entity5 cell lines versus normal tissue. METHODS: We performed reverse transcription PCR from 29 tissue specimens of @entity957 and one @entity320 and of the @entity135 as well as from 13 cell lines established from @entity135 . We were looking for the expression pattern of @entity4879 , beta, gamma and RXRalpha. RESULTS: Only @entity19713 was expressed 100 % in cell lines and tissue specimens. @entity4882 showed a 100 % expression only in tissue specimens whereas a 54 % expression in cell lines was seen. All other receptors were diminished in their expression. In the positive controls all receptors were expressed 100 %. CONCLUSION: The expression of @entity4879 and @entity4882 was partially lost in cell lines established from @entity957 of the @entity135 . The 100 % expression of @entity4882 in tissue samples versus 54 % in cell lines can be explained by clonal growth of malignant cells in cell lines and also possible "contamination" by normal cells in the tissue specimen. In concordance with the literature it seems that @entity4879 and beta play a pivotal role in mediating the response to @entity4878 .

[Expression of XXXX receptors in @entity135 @entity957 and their possible implication for chemoprevention].

@entity135 :: ('MESH:D006258', 'Disease') :: ['head and neck', 'head and neck cancer'] @entity19713 :: ('5916', 'Gene') :: ['RARgamma'] @entity4878 :: ('MESH:D012176', 'Chemical') :: ['retinoids', 'Retinoids'] @entity320 :: ('MESH:D008545', 'Disease') :: ['melanoma'] @entity4879 :: ('5914', 'Gene') :: ['RARalpha'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'cancers', 'malignant tumors'] @entity957 :: ('MESH:D002294', 'Disease') :: ['squamous cell carcinoma', 'squamous cell carcinomas'] @entity272 :: ('MESH:D012871', 'Disease') :: ['skin diseases'] @entity4882 :: ('5915', 'Gene') :: ['RARbeta'] @entity1968 :: ('MESH:D014212', 'Chemical') :: ['retinoic acid', 'Retinoic acid']
@entity1968 :: (MESH:D014212,Chemical) :: ['retinoic acid']
