The value of Phosphohistone H3 as a cell proliferation marker in oral squamous cell carcinoma. A comparative study with Ki-67 and the mitotic activity index.

BACKGROUND: The Phosphohistone H3 (PHH3) antibody is recognized as a biomarker of cell proliferation, specific for cells in mitosis, of prognostic value in different malignant neoplasms, however it has been poorly studied in oral squamous cell carcinoma (OSCC). The main objective of this study was to evaluate the immunoexpression of the PHH3 in the OSCC, through the correlation with the immunoexpression of Ki-67, the mitotic activity index (MAI), histological grading, clinical-morphological parameters and the rate of survival.

MATERIAL AND METHODS: The study sample consisted of 62 cases of OSCC diagnosed in the Pathological Anatomy Laboratory of the Faculty of Dentistry, University of the Republic (Uruguay). In each of them, an immunohistochemical technique was performed for Ki-67 and PHH3 (serine 10) antibodies. Image J software was used for the MAI and biomarker quantification, defining the percentage of positivity and mitotic figures per 1000 tumor cells.

RESULTS: a significant association was obtained between the expression of PHH3 (p 0.016) and MAI (p 0.031) with survival time. However, no similar relationship was found with Ki-67 (p 0.295). Although it was confirmed a statistical association between histological grade and Ki-67 immunoexpression (p 0.004), PHH3 did not show a similar relationship (p 0.564).

CONCLUSIONS: It was confirmed the role of the PHH3 antibody as a biomarker of mitotic figures in OSCC and as a potential marker of cell proliferation. It is noteworthy that this is one of the first works that evaluates a possible relationship between the expression of this antibody and survival in OSCC.