| Beta defensin 1 , parvalbumin , and vimentin : a panel of diagnostic immunohistochemical markers for renal tumors derived from gene expression profiling studies using cDNA microarrays . ^^^ In this report we validated differential expression of three candidate markers , beta defensin 1 , parvalbumin , and vimentin , and evaluated the use of this immunohistochemical panel as a potential diagnostic tool . ^^^ Consistent with our cDNA microarray data , chromophobe RCCs and oncocytomas exhibited similar expression profiles : 8 of 8 examples of each subtype were immunohistochemically positive for beta defensin 1 and parvalbumin and negative for vimentin ( sensitivity 100 % , specificity 100 % ) ; 4 of 7 papillary RCCs were positive for beta defensin 1 , parvalbumin , and vimentin ( sensitivity 57 % , specificity 97 % ) ; and 22 of 23 conventional RCCs were negative for beta defensin 1 , parvalbumin , or both markers ( sensitivity 96 % , specificity 96 % ) as well as positive for vimentin ( sensitivity 83 % ) . ^^^ |