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Immunocytochemical Expression of BAX and BAK Proteins in Cervical Smears of Women Positive for HPV Types: A Study of 120 Cases

Eirini Klapsinou, Elena Argyri, Efstathia Panotopoulou, Dimitra Daskalopoulou, Efstratios Patsouris, Afroditi Nonni, Andreas C Lazaris, Georgia-Heleni Thomopoulou


Objective: Human Papillomavirus (HPV) infection is clearly associated with cervical cancer development. However, only a very small percentage of HPV-infected women will eventually develop cancer and the factors determining that progression have not yet been sufficiently clarified. It is known that HPV oncoproteins E6 and E7 interact with various squamous cell molecules towards promoting cell immortalization and carcinogenesis. Among these molecules are the proapoptotic proteins Bax and Bak, two key regulators of the intrinsic apoptotic pathway. The aim of this study is to test for possible statistically significant differences in the Bax and Bak expression in the Pap smears of HPV-positive and HPV-negative women and thus examine their potential value as prognostic markers.

Methods: One hundred and twenty women were subtyped for HPV using microarrays hybridization and then Bax and Bak expression was assessed using immunocytochemistry staining on cytocentrifuged ThinPrep samples.

Results: Statistical analysis determined that there was no statistically significant difference between the expression of Bax and Bak in the HPV-positive and HPV-negative women as this expression was detected by immunocytochemical assessment of ThinPrep samples.

Conclusion: Although in several published studies there is evidence of HPV oncoproteins affecting the expression of Bax and Bak on squamous cells, our study indicates that this effect is not apparent by immunocytochemical protein staining.


Bax; Bak; cytology; cervical smears

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