Visual and Image Cytometric Analysis of Apoptosis in Hepatocellular Carcinoma: Correlation with Proliferation, Prognostic Parameters, and Survival.
Jason Wang, Neeraj K Saxena, Cynthia Cohen. Emory University School of Medicine, Atlanta
Background: The incidence of hepatocellular carcinoma (HCC) is increasing worldwide. Programmed cell death, named apoptosis in the 1970s, has led to various therapeutic efforts. The caspase and BCL2 family of proteins are fundamental to the molecular cascade necessary for apoptosis. In the BCL2 family, Bax promotes cell death while BCL2 itself encourages survival. Caspase 3 is necessary for the caspase cascade which, upon activation, is responsible for the morphologic changes characteristic of apoptosis. Survivin, a member of the inhibitor of apoptosis gene family, inhibits apoptosis and is implicated in the regulation of mitosis and promotion of angiogenesis.
Design: 135 HCCs in 3 tissue microarrays with 2 1mm cores of each tumor were immunostained for survivin, activated caspase 3, Bax, and BCL2 expression and scored as intensity 0-3+ and % + cells. Results were compared to proliferation (mitoses/10HPF, MIB-1 visual mean, visual high and labeling index [LI], phosphohistone-3[PPH3] visual mean, visual high and LI), prognostic parameters (size, grade, stage, angiolymphatic invasion [ALI], metastases, focality, local recurrence [LR]), and survival. LI was determined with the ACIS III Image Cytometer (Dako).
Results: Positive staining is defined as 2-3+ intensity. Of the 135 HCCs, 58 (43%) had + nuclear survivin, 112 (83%) + cytoplasmic survivin, 85 (63%) + caspase 3, 109 (81%) + Bax and 4 (3%) + BCL2 expression. Statistically significant correlations are summarized as follows:
|Survivin - Nuclear||Focality||0.04|
|Survivin - Cytoplasmic||MIB LI||0.05|
|MIB Visual Mean||0.05|
|MIB Visual High||0.03|