Comparison of ACINUS, caspase-3, and TUNEL as apoptotic markers in determination of tumor growth rates of clinically localized prostate cancer using image analysis.
BACKGROUND
The balance between apoptotic and proliferative processes determines the enlargement of a tumor. Accurate measurement of apoptotic and proliferative rates from diagnostic prostate biopsies would allow calculation of tumor growth rates in a population-based prostate cancer (CaP) study. Automated image analysis may be used if proliferation and apoptotic biomarkers provide clearly resolved immunostained images.


METHODS
Clinical CaP aggressiveness was assigned as low, intermediate or high using clinical criteria for 46 research subjects with newly diagnosed CaP. Diagnostic biopsy sections from the research subjects were dual-labeled for proliferation biomarker, Ki-67 and apoptotic biomarker, apoptotic chromatin condensation inducer in the nucleus (ACINUS). Apoptotic biomarkers, caspase-3 and terminal deoxyribonucleotidyltransferase mediated dUTP-biotin nick end labeling (TUNEL) were labeled separately. Images from immunostained sections were analyzed using automated image analysis and tumor growth rates computed. Association between clinical CaP aggressiveness and tumor growth rates was explored.


RESULTS
Sixteen subjects had high, 17 had intermediate, and 13 had low clinical CaP aggressiveness. Positive immunostaining was localized to the nucleus for Ki-67, ACINUS, and TUNEL. A statistically significant linear trend across clinical CaP aggressiveness categories was found when tumor growth rates were calculated using ACINUS (P = 0.046). Logistic regression and ROC plots generated showed ACINUS (AUC = 0.677, P = 0.048) and caspase-3 (AUC = 0.694, P = 0.038) to be better predictors than TUNEL (AUC = 0.669, P = 0.110).


CONCLUSIONS
ACINUS met the criteria for automated image analysis and for calculation of apoptotic rate. Tumor growth rates determined using automated image analysis should be evaluated for clinical prediction of CaP aggressiveness, treatment response, recurrence, and mortality.
Singh
Swaroop S
SS
Department of Urology, Roswell Park Cancer Institute, Buffalo, New York.
Mehedint
Diana C
DC
Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
Ford
O Harris
OH
Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
Jeyaraj
D Antony
DA
Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
Pop
Elena A
EA
Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
Maygarden
Susan J
SJ
Department of Pathology and Laboratory Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
Ivanova
Anastasia
A
Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.|Department of Biostatistics, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
Chandrasekhar
Rameela
R
Department of Biostatistics, Roswell Park Cancer Institute, Buffalo, New York.|Department of Biostatistics, State University of New York, Buffalo, New York.
Wilding
Gregory E
GE
Department of Biostatistics, Roswell Park Cancer Institute, Buffalo, New York.|Department of Biostatistics, State University of New York, Buffalo, New York.
Mohler
James L
JL
Department of Urology, Roswell Park Cancer Institute, Buffalo, New York.|Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.|Department of Surgery, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.|Department of Urology, State University of New York, Buffalo, New York.
D017209:Apoptosis / Q000502:physiology; D014408:Biomarkers, Tumor / Q000032:analysis*; D001706:Biopsy; D053148:Caspase 3 / Q000032:analysis*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D019394:Ki-67 Antigen / Q000032:analysis*; D016015:Logistic Models; D008297:Male; D009687:Nuclear Proteins / Q000032:analysis*; D011237:Predictive Value of Tests; D011471:Prostatic Neoplasms / Q000378:metabolism / Q000473:pathology*; D012372:ROC Curve
C121310:ACIN1 protein, human; D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D009687:Nuclear Proteins; D053148:Caspase 3