Simultaneous detection of imprinted gene expression (p57(KIP2)) and molecular cytogenetics (FICTION) in the evaluation of molar pregnancies.
OBJECTIVE
To simultaneously evaluate the p57(KIP2) antibody expression and genotype of individual cells from paraffin sections of molar pregnancies.


METHODS
Paraffin sections from 10 typical and unusual molar pregnancies were evaluated with the FICTION technique (Fluorescence Immunophenotyping and Interphase Cytogenetics as a Tool for the Investigation of Neoplasms), using immunofluorescence staining for the p57(KIP2) antibody and enumeration fluorescence in situ hybridization (FISH) probes. The unusual cases included androgenetic/ biparental chimeric complete hydatidiform moles (CHM) and mosaic partial hydatidiform moles (PHM). The unusual molar conceptions provided insight into interpreting atypical p57(KIP2) staining patterns and identifying androgenetic cells.


RESULTS
The androgenetic/biparental chimeric CHMs demonstrated a negative p57(KIP2) Staining pattern for the androgenetic cells and positive staining for the biparental cells. Concordantly, the FISH results showed delineation between the androgenetic cells and the biparental cells, indicating 2 distinct genotypes. Also, in the 2 cases of mosaic PHM, the partial loss of p57(KIP2) antibody staining was due to mosaic loss of chromosome 11, assumed to be the maternal copy. This provides a biological explanation as to how false interpretation could occur when evaluating p57(KIP2) immunostaining results.


CONCLUSIONS
The FICTION technique is a valuable ancillary tool for simultaneously evaluating the genotype and p57(KIP2) expression in unusual molar pregnancies.
Hoffner
Lori
L
Magee-Women's Research Institute, Pittsburgh, PA 15213, USA.
Parks
W Tony
WT
Swerdlow
Steven H
SH
Carson
Jason C
JC
Surti
Urvashi
U
D001323:Autoantibodies / Q000032:analysis* / Q000378:metabolism; D002678:Chimera / Q000235:genetics*; D050761:Cyclin-Dependent Kinase Inhibitor p57 / Q000235:genetics* / Q000276:immunology; D005260:Female; D015870:Gene Expression; D006801:Humans; D006828:Hydatidiform Mole / Q000235:genetics* / Q000473:pathology; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping / Q000379:methods; D009030:Mosaicism; D011247:Pregnancy; D014594:Uterine Neoplasms / Q000235:genetics* / Q000473:pathology
D001323:Autoantibodies; D050761:Cyclin-Dependent Kinase Inhibitor p57