TY - JOUR
T1 - A tissue quality index
T2 - An intrinsic control for measurement of effects of preanalytical variables on FFPE tissue
AU - Neumeister, Veronique M.
AU - Parisi, Fabio
AU - England, Allison M.
AU - Siddiqui, Summar
AU - Anagnostou, Valsamo
AU - Zarrella, Elizabeth
AU - Vassilakopolou, Maria
AU - Bai, Yalai
AU - Saylor, Sasha
AU - Sapino, Anna
AU - Kluger, Yuval
AU - Hicks, David G.
AU - Bussolati, Gianni
AU - Kwei, Stephanie
AU - Rimm, David L.
N1 - Funding Information:
We thank Ms Lori Charette and her team in at Yale Pathology Tissue Services for TMA construction and tissue sectioning. This project has been funded in whole or in part with federal funds from the National Cancer Institute, National Institutes of Health, under Contract No. HHSN261200800001E. The content of this publication does not necessarily reflect the views or policies of the Department of Health and Human Services, nor does the mention of trade names, commercial products, or organizations imply endorsement by the US Government. This work was also supported by Ricerca Sanitaria Finalizzata RF-2010-2310674.
PY - 2014/4
Y1 - 2014/4
N2 - While efforts are made to improve tissue quality and control preanalytical variables, pathologists are often confronted with the challenge of molecular analysis of patient samples of unknown quality. Here we describe a first attempt to construct a tissue quality index (TQI) or an intrinsic control that would allow a global assessment of protein status based on quantitative measurement of a small number of selected, informative epitopes. Quantitative immunofluorescence (QIF) of a number of proteins was performed on a series of 93 breast cancer cases where levels of expression were assessed as a function of delayed time to formalin fixation. A TQI was constructed based on the combination of proteins that most accurately reflect increased and decreased levels of expression in proportion to delay time. The TQI, defined by combinations of measurements of cytokeratin, ERK1/2 and pHSP-27 and their relationship to cold ischemic time were validated on a second build of the training series and on two independent breast tissue cohorts with recorded time to formalin fixation. We show an association of negative TQI values (an indicator for loss of tissue quality) with increasing cold ischemic time on both validation cohorts and an association with loss of ER expression levels on all three breast cohorts. Using expression levels of three epitopes, we can begin to assess the likelihood of delayed time to fixation or decreased tissue quality. This TQI represents a proof of concept for the use of epitope expression to provide a mechanism for monitoring tissue quality.
AB - While efforts are made to improve tissue quality and control preanalytical variables, pathologists are often confronted with the challenge of molecular analysis of patient samples of unknown quality. Here we describe a first attempt to construct a tissue quality index (TQI) or an intrinsic control that would allow a global assessment of protein status based on quantitative measurement of a small number of selected, informative epitopes. Quantitative immunofluorescence (QIF) of a number of proteins was performed on a series of 93 breast cancer cases where levels of expression were assessed as a function of delayed time to formalin fixation. A TQI was constructed based on the combination of proteins that most accurately reflect increased and decreased levels of expression in proportion to delay time. The TQI, defined by combinations of measurements of cytokeratin, ERK1/2 and pHSP-27 and their relationship to cold ischemic time were validated on a second build of the training series and on two independent breast tissue cohorts with recorded time to formalin fixation. We show an association of negative TQI values (an indicator for loss of tissue quality) with increasing cold ischemic time on both validation cohorts and an association with loss of ER expression levels on all three breast cohorts. Using expression levels of three epitopes, we can begin to assess the likelihood of delayed time to fixation or decreased tissue quality. This TQI represents a proof of concept for the use of epitope expression to provide a mechanism for monitoring tissue quality.
KW - epitope degradation
KW - immunofluorescence
KW - immunohistochemistry
KW - preanalytic variables
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U2 - 10.1038/labinvest.2014.7
DO - 10.1038/labinvest.2014.7
M3 - Article
C2 - 24535259
AN - SCOPUS:84896029611
SN - 0023-6837
VL - 94
SP - 467
EP - 474
JO - Laboratory Investigation
JF - Laboratory Investigation
IS - 4
ER -