Bcl-2 family immunohistochemistry

In recent years, immunohistochemistry as applied to the Bcl-2 family of proteins has represented a burgeoning area of interest to cancer researchers. The majority of studies have focused on the original member Bcl-2, first identified via its involvement in the common t(14;18) chromosomal translocation in B-cell lymphomas (1). However, since this discovery, preclinical and clinical interest in Bcl-2 has dramatically increased owing to (a) its recognition as the first of a new class of oncogene able to prolong survival by inhibiting programmed cell death (apoptosis) and (b) the discovery of many additional related genes/proteins some of which, like Bcl-2, inhibit apoptosis, whereas others, such as Bax, conversely promote cell death (2) (Table 1). Table 1 Bcl-2 Family Members Pro-apoptotic Anti-apoptotic Bax Bcl-2 Bcl-Xs Bcl-Xl Bak Bcl-w Bad Bfl-1 Bid Brag-1 Bik Mcl-1 Hrk A1.