Sensitivity of XXXX antibodies in archival tissue samples: potential source of error in immunohistochemical studies of oncogene expression.

@entity1 @entity982 @entity0 @entity1722
@entity1722 oncogene amplification and overexpression of @entity0 tissue has been correlated with poor prognosis in @entity1 with both node-positive and node-negative disease. However, several studies have not confirmed this association. Review of these studies reveals the presence of considerable methodological variability including differences in study size, follow-up time, techniques and reagents. The majority of papers with clinical follow-up information are immunohistochemical studies using archival, paraffin-embedded @entity0 , and a variety of @entity1722 antibodies have been used in these studies. Very little information, however, is available about the ability of the antibodies to detect overexpression following tissue processing for paraffin-embedding. Therefore, a series of antibodies, reported in the literature or commercially available, were evaluated to assess their sensitivity and specificity as immunohistochemical reagents. @entity982 -embedded samples of 187 @entity0 , previously characterized as frozen specimens for @entity1722 /neu amplification by Southern blot and for overexpression by Northern blot, Western blot, and immunohistochemistry, were used. Two multitumor paraffin-embedded tissue blocks were prepared from the previously analyzed @entity0 as a panel of cases to test a series of previously studied and/or commercially available anti- @entity1722 antibodies. Immunohistochemical staining results obtained with 7 polyclonal and 21 monoclonal antibodies in sections from paraffin-embedded blocks of these @entity0 were compared. The ability of these antibodies to detect overexpression was extremely variable, providing an important explantation for the variable overexpression rate reported in the literature.
