Increased spontaneous apoptosis, but not survivin expression, is associated with histomorphologic response to neoadjuvant chemoradiation in rectal cancer.
OBJECTIVE
Survivin has been shown to be an important mediator of cellular radioresistance in vitro. This study aims to compare survivin expression and apoptosis to histomorphologic responses to neoadjuvant radiochemotherapy (RCT) in rectal cancer.


METHODS
Thirty-six pre-treatment biopsies were studied. Survivin mRNA and protein expression plus TUNEL staining for apoptosis was performed. Response to treatment was assessed using a 5-point tumour regression grade.


RESULTS
Survivin expression was not found to be predictive of response to RCT (p = NS). In contrast, spontaneous apoptosis was significantly (p = 0.0051) associated with subsequent response to RCT. However, no association between survivin expression and levels of apoptosis could be identified.


CONCLUSIONS
This in vivo study failed to support in vitro studies showing an association between survivin and response to chemotherapy and radiation therapy. These results caution against the translation of the in vitro properties of survivin into a clinical setting.
McDowell
Dermot T
DT
Department of Academic Surgery, St James's Hospital, Dublin, Ireland.
Smith
Fraser M
FM
Reynolds
John V
JV
Maher
Stephen G
SG
Adida
Collette
C
Crotty
Paul
P
Gaffney
Eoin F
EF
Hollywood
Donal
D
Mehigan
Brian
B
Stephens
Richard B
RB
Kennedy
M J
MJ
D017209:Apoptosis; D001706:Biopsy; D049109:Cell Proliferation; D017024:Chemotherapy, Adjuvant; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D019394:Ki-67 Antigen / Q000378:metabolism; D008198:Lymph Nodes / Q000473:pathology; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D018714:Radiotherapy, Adjuvant; D012004:Rectal Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000532:radiotherapy*; D013194:Staining and Labeling; D000077022:Survivin
C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D019394:Ki-67 Antigen; D008869:Microtubule-Associated Proteins; D000077022:Survivin