H. Khalid et al., IMMUNOHISTOCHEMICAL ANALYSIS OF PROGESTERONE-RECEPTOR AND KI-67 LABELING INDEX IN ASTROCYTIC TUMORS, Cancer, 80(11), 1997, pp. 2133-2140
BACKGROUND. Intracranial tumors such as meningiomas express steroid ho
rmone receptors but little is known regarding progesterone receptor (P
R) in astrocytic tumors. The authors evaluated expression of PR in 86
astrocytic tumors in relation to tumor proliferative potential. METHOD
S. Paraffin embedded tumor sections were stained with polyclonal antip
rogesterone antibody by the peroxidase-antiperoxidase method and with
monoclonal MIB-1-Ki-67 antibody by avidin-biotin complex immunohistoch
emistry. RESULTS. Sixty-three of the 86 astrocytic tumors (73%) showed
positive PR immunoreactivity. PR expression was observed in 4 of 9 pi
locytic astrocytomas, 13 of 24 Grade 2 astrocytomas, 15 of 20 anaplast
ic astrocytomas, and 31 of 33 glioblastomas. In addition to the tumor
cells, cells of microvascular endothelial proliferation and the smooth
muscle of tumor vessel walls were frequently PR positive. Glioblastom
as had a significantly higher percentage of PR positive cells compared
with anaplastic (P < 0.0008) and low grade (P < 0.0001) astrocytomas.
Patients with PR positive astrocytomas were of an older age than pati
ents with PR negative astrocytomas (48.71 +/- 21.95 years vs. 37.09 +/
- 24.69 years; P < 0.04). The mean Ki-67 labeling index (LI) was signi
ficantly higher in the high grade (3-4) astrocytomas compared with low
grade (1-2) astrocytomas (P < 0.0001). PR positive astrocytic tumors
had higher Ki-67 LI than PR negative tumors. PR expression was not cor
related with tumor recurrence and patient survival. CONCLUSIONS. The c
urrent study suggests that PR in the astrocytic tumors correlates with
histologic grade and PR may participate in the growth of these tumors
and tumor angiogenesis. The measurement of PR in these tumors may ind
irectly represent tumor growth potential. (C) 1997 American Cancer Soc
iety.