Histone mRNA in-situ hybridization in astrocytomas: a comparison with PCNA, MIB-1 and mitoses in paraffin-embedded material.
OBJECTIVE
Non-isotopic histone mRNA in-situ hybridization (HmRNA NISH) allows detection of cells in the S phase of the cell cycle in paraffin-embedded tissue. The aim of this study was to evaluate the technique in measuring the proliferative activity of astrocytic neoplasms, and to compare the results with other proliferation estimates and patient survival.


RESULTS
The proliferative activity of 71 routinely fixed and paraffin-embedded astrocytomas was studied by light microscopic HmRNA NISH, proliferating cell nuclear antigen (PCNA), Ki67MIB-1 and mitoses. A significant correlation was found between the labelling indices of histone mRNA (the percentage of histone-positive tumour cells: HmRNA-LI), immunohistochemical proliferation marker labelling indices (PCNA-LI: r = 0.64 and Ki67MIB-1-LI: r = 0.44) and mitotic indices (r = 0.45). The results were reproducible as judged by intra- and interobserver agreement (HmRNA/10 HPF (high power fields): r = 0.91 and r = 0.75, respectively, and HmRNA-LI: r = 0.61 and r = 0.62, respectively). The fraction of the cells in the most active cell cycle phases, as suggested by the HmRNA/Ki67 and mitotic index/Ki67 ratios, increased significantly with malignancy grade. In the univariate analysis the association of HmRNA-LI with survival was highly significant (P < 0.0001). Multivariate survival analysis showed that HmRNA-LI was an independent prognostic marker.


CONCLUSIONS
Non-isotopic histone mRNA in-situ hybridization assay offers an alternative and reproducible method for measuring proliferative activity (S phase) in tumours under morphological control.
Rautiainen
E
E
Department of Pathology, Tampere University Hospital, Finland.
Haapasalo
H
H
Sallinen
P
P
Rantala
I
I
Helen
P
P
Helin
H
H
D034961:Antigens, Nuclear; D001254:Astrocytoma / Q000737:chemistry / Q000235:genetics*; D001932:Brain Neoplasms / Q000737:chemistry / Q000235:genetics*; D003627:Data Interpretation, Statistical; D019793:Fluorescein; D015870:Gene Expression / Q000235:genetics; D006657:Histones / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D019394:Ki-67 Antigen / Q000032:analysis; D008938:Mitosis / Q000235:genetics / Q000502:physiology; D009687:Nuclear Proteins / Q000032:analysis; D015588:Observer Variation; D016612:Paraffin Embedding; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis* / Q000235:genetics; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013194:Staining and Labeling; D016019:Survival Analysis
D034961:Antigens, Nuclear; D006657:Histones; D019394:Ki-67 Antigen; D009687:Nuclear Proteins; D018809:Proliferating Cell Nuclear Antigen; D012333:RNA, Messenger; D019793:Fluorescein