Level of phosphohistone H3 among various types of human cancers

Abstract

ObjectivesAnti-phosphorylated histone H3 (pHH3) antibodies specifically detect the core protein histone H3 only when phosphorylated at serine 10 (Ser10) or serine 28 (Ser28). Measurement of pHH3 levels can be used for quantifying mitosis and the effectiveness of mitotic inhibitors in early drug development. However, data on the expression level of pHH3 (Ser10) and pHH3 (Ser28) among different cancers are limited. This study was designed to investigate the expression levels of pHH3 across different types of cancers, using uniform techniques and assay platforms in a single laboratory.DesignRetrospective study.SettingSingle laboratory.SpecimensFormalin-fixed, paraffin-embedded various human cancer specimens were provided by Mosaic Laboratories Tissue Bank.Primary and secondary outcome measuresUsing immunohistochemistry, pHH3 levels were measured using both pHH3 (Ser10) and (Ser28) antibodies among 10 human melanoma and 10 ovarian tumour samples. The samples were reviewed blindly by two reviewers. pHH3 (Ser10) was then selected to measure the pHH3 levels in cancers of breast, colorectal, oesophageal, gastric, head and neck and lung (n=5 for each cancer).ResultsThe pHH3 (Ser10) expression was higher than pHH3 (Ser28) in both melanoma and ovarian cancers (p<0.01), with the mean (SD) levels of 1.28% (0.47%) for Ser10 and 0.53% (0.44%) for Ser28 among melanoma and 3.47% (3.51%) for Ser10 and 0.62% (0.68%) for Ser28 among ovarian cancers, respectively. No statistically significant differences were observed among different cancer types tested for pHH3 using Ser10 (p=0.197). No reviewer effect was identified.ConclusionsThe pHH3 Ser10 was significantly higher than Ser28 and may serve as the more robust of two pHH3 assays for measuring mitotic index.

Mitotic Index is an Independent Predictor of Recurrence‐Free Survival in Meningioma

“…The anti‐pHH3 (Ser10) antibody is highly sensitive for mitotic figure detection, is commercially available and is amenable to use on FFPE tissues . The use of pHH3 immunostain for mitotic figure detection offers the possibility of defining a more objective mitotic index, as compared to the current practice of counting mitoses per unit area.…”

Immunodetection of phosphohistone H3 as a surrogate of mitotic figure count and clinical outcome in cutaneous melanoma

“…Thus, immunodetection of phosphohistone H3 has become a sensitive and specific marker of mitotic figures and correlates with outcome in a variety of different human tumor types, 9 including breast carcinoma, 10,11 colorectal adenocarcinoma, 12 ovarian serous adenocarcinoma, 13 pulmonary neuroendocrine carcinoma, 14 uterine smooth muscle tumors, 15 astrocytomas, 16 and meningiomas. 17 In melanoma, immunodetection of phosphohistone H3 has been shown to increase the sensitivity and accuracy for mitotic figure detection; it improves inter-observer variability; and it reduces the time required to identify mitoses in primary cutaneous and uveal melanomas.…”

The mitosis‐specific marker phosphohistone‐H3 (PHH3) is an independent prognosticator in uterine smooth muscle tumours: an outcome‐based study

“…Concerning practical issues associated with PHH3 immunohistochemical staining, several points need to be emphasized. Among commercially available PHH3 antibodies, we opted to use Ser10, as it has been shown to be more robust than Ser28, and its use in earlier studies for USMTs would allow better comparisons . For the best quality and intensity of staining, the tissue sections should be freshly cut and prepared from paraffin blocks, with PHH3 staining being performed within 2 days.…”