Immunohistochemical detection of acetylation and phosphorylation of histone H3 in cervical smears

M Anton, MD, a M Horký, MD, a V Kotala, MD, a B Vojtìsek, DrSc, a O Bláha, MD b

aMasaryk Oncological Institute, Brno, Czech Republic Czech Republic bDept.Obstet.Gynecol., Medical Faculty, Masaryk University, Brno, Czech Republic

Objective: Histones bind in a sequence-independent manner to form chromatin. The amini-terminal tails of histones are targets for both phosphorylation and acetylation events. These modifications are thought to fundamentally regulate chromatin structure to accommodate transcription, DNA replication, mitosis and DNA repair. Regeneration of squamous and columnar epithelia is accompanied by marked cellular atypia, nuclear and nucleolar pleomorphism which could be confused with neoplasia. The aim of the study was to detect phosphorylated and acetylated forms of H3 (histone-3) in cytological smears. Methods: Smears from women whose ages ranged from 20 to 56 yrs, undergoing routine Papanicolaou tests were selected. The smears were evaluated for abnormal cells according to the traditional nomenclature. The specimens comprised 5 squamous metaplasia, 5 epithelial repair, 3 CIN I, 4 CIN II, and 7 CIN III. The smears were stained with polyclonal antibodies against phosphorylated and acetylated forms of H3. Results: We found nuclear positivity for phosphorylated (P) and acetylated (A) forms of H3 in CIN II (23%P, 33%A) and CIN III (25%P,44 %) was higher in comparison with repair (11%P,12%A) and metaplasia (8%P, 15%A). Conclusion: We revealed a marked association of histone H3 modifications with the progression of CIN in comparison to cervical repair and metaplasia. Our results are in agreement with recent findings: (1) staining of cells with anti-phospho-histoneH3 antibodies therefore provides a highly specific marker for mitosis.(2) acetylation of nucleosomal histones correlates with localized transcriptional activity.

KEY WORDS: cervical carcinogenesis, mitoses, histone, .

For more information, contact

Paper presented at the International Symposium on Predictive Oncology and Intervention Strategies; Paris, France; February 9 - 12, 2002; in the section on Diagnostic Markers.