Immunohistochemical expression of anti-apoptotic protein bcl2 and its correlation with hormone receptors in breast cancers

Abstract

Objectives One of the novel benefits of immunohistochemistry in human malignancy (in addition to its major role in confirming the
diagnosis) is to discover specific therapeutic targets in cancer cells, so this study was conducted to identify immunohistochemical
expression of bcl2 in breast cancers, and to correlate its expression with expression of hormone receptors (estrogen and progesterone) to
provide histologic information that may help in clinical practice.
Methods This is a retrospective study that at the histopathology laboratory at Alwasity teaching hospital for orthopedic and plastic surgery
in Bagdad, about 52 paraffin-embedded tissue blocks of cases diagnosed as primary mammary carcinoma, which were retrieved from
multiple private sectors in Bagdad. From each block, four histological sections were made, one stained with hematoxylin and eosin to
examine under light microscope and the other three histological sections were processed for immunohistochemical staining with
antibodies to estrogen receptors (ERs), progesterone receptors (PRs) and bcl2. The results of immunohistochemistry were statistically
evaluated.
Results Of 52 samples with breast cancer, 42(80.7%) were ductal and 10(19.2%) were lobular. The study showed that 26(50%) of total
sample were positive for ERs and 34(65.3%) were positive for PRs. Regarding bcl2, 26(50%) of total samples were immunoreactive for the
latter, and there is a highly significant statistical relationship between the expression of bcl2 and (ERs and PRs).
Conclusion Bcl2 immunohistochemical expression can be found in breast cancer and its expression is strongly correlate with ER and PR
status and the former can be used as a predictive marker that predicts positive immunohistochemical expression of hormone receptors
(thereby hormone receptor therapy) and vice versa and can be used as a quality control marker. This conclusion can be used to standardize
immunohistochemistry for this application.