p40 antibody as marker for prostate basal and squamous cells

Overview

The anti p40 antibody is currently replacing p63 as the optimum marker for basal cells of the prostate gland. Recent evidence suggests P40 is a more specific marker than p63 for squamous cells, especially in newly developed BC28 form, now available from Nordic BioSite. This implies that p40 is superior to p63 as a marker for lung and urothelial carcinomas, squamous and basal cell skin cancers, as well as in head and neck cancers of squamous cell origin.

Background

The p40 antibody, like p63 is detected in prostate basal cells in normal and premalignant prostate glands. Until recently no studies addressed p40 staining in prostate cancer were available.

New studies have indicated that when directed against an N-terminal truncated form of the p63 protein (ΔNp63), p40 has shown higher specificity for squamous cells than p63.

In oncology, p63 has also been one of the standard markers most widely used to distinguish between adenocarcinoma and squamous cell carcinoma of the lung.

The polyclonal p40 antibody used in this study showed cytoplasmic background in some cases. However, Nordic BioSite can supply recently developed monoclonal p40 (BC28) that shows no background and is especially useful in cocktails with P504S, a marker for prostate cancer and premalignant stages.

P40 in prostate cancer

Sailer et al. from the Charité in Berlin addressed the question whether p40 or p63 is the marker of choice in prostate cancer diagnostics [3].

The study compared the most widely used p63 clone, 4A4, with the p40 polyclonal antibody in a semi quantitative manner, with immunostaining performed on 640 malignant and normal prostate tissues. The study found staining pattern of normal tissue almost identical for p40 and p63.

More important differences were seen in staining of carcinomas: with 1.4 per cent of the nuclei staining positive with antibody p63 whereas only 0.6 per cent stained positive for p40.

The authors concluded that p40 is as reliable in prostate diagnostics as p63 and emphasized the higher specificity of p40 in showing less than half the false positive staining of aberrant cells.

P40 in lung and other cancers

A new study comparing the performance of the new monoclonal p40 antibody with that of the polyclonal in lung carcinoma demonstrates that both sensitivity and specificity are the same.4 The p40 monoclonal staining was observed in a greater percentage of urothelial carcinomas, squamous and basal cell skin cancers, as well as in head and necks cancers of squamous cell origin when compared to p63. In prostate, no adenocarcinoma showed positive staining for p40 with the monoclonal antibody.

The p40 expression in basal cells of prostate glands and prostatic intraepithelial neoplasia were almost identical to those of p63.

Taken together, the study findings suggest that p40 appears to be superior to p63 as a marker for both lung and prostate diagnostics.

P40 Specifications

Sources:

1. Nonaka, D. (2012), “A study of DeltaNp63 expression in lung non-small cell carcinomas”: American Journal of Surgery and Pathology 36: pp895–899, 2012
2. Bishop, J.A. et al. (20-12) “p40 (ΔNp63) is superior to p63 for the diagnosis of pulmonary squamous cell carcinoma”: Modern Pathology 25:405–415.
3. Sailer, V. et al. (2013): “Comparison of p40 (ΔNp63) and p63 expression in prostate tissues-which one is the superior diagnostic marker for basal cells?” Histopathology 63: pp.50-56.
4. Tacha. D. et al. (2014): “An immunohistochemical analysis of a newly developed, mouse monoclonal p40 (BC28) in lung, bladder, skin, breast, prostate, and head and neck cancers”. Archives of Pathology & Laboratory Medicine, Feb 14. [Epub ahead of print].

Resources

Click on P40 marker for prostate basal cells for more information.
Click on Nordic Biosite to contact the company directly.

Supplier Information
Supplier: Nordic Biosite
Address: Propellervägen 4A, 183 62 Täby, Sweden
Tel: +46 (0)8 544 433 40
Fax: +46 (0)8 756 94 90
Website: www.nordicbiosite.com