Abstract 4665: A combined IHC/Western method to measure phosphorylated histone H3 in skin biopsies as potential biomarker for anticancer drug action

• Published in: Cancer research (Chicago, Ill.) Ill.), 2010-04, Vol.70 (8_Supplement), p.4665-4665
• Main Authors: Graeser, Ralph, Birkle, Marianne, Rentzsch, Christine, Schaechtele, Christoph
• Format: Article
• Language: English
• ISSN: 0008-5472; 1538-7445
• DOI: 10.1158/1538-7445.AM10-4665

In recent years there has been a rapid increase in targeted tumor therapy approaches. Hand in hand with these novel approaches, the need has arisen to monitor specific target inhibition by the drug. In contrast to classic chemotherapy, which non-specifically targets proliferating cells, these novel approaches attempt to specifically interfere with some process thought to be crucial for the tumor cell survival. Nevertheless, despite extensive validation, an immediate effect of target interference on tumor growth may not necessarily be expected. Thus, in order to demonstrate activity of anti-cancer drugs, a marker known to be modified upon inhibition of the target may serve as a surrogate to tumor inhibition. Ideally, tumor biopsies would be analysed for monitoring of drug-induced effects. However, taking in consideration the difficulties to perform sequential tumor biopsies, the use of surrogate tissues like blood or skin is being explored instead. Blood is relatively easily accessible, but unlike skin tissue, blood may not reflect the fact that drugs have to penetrate multiple layers of tissue in order to reach their target in the tumor. Also, to monitor the effects of anti-mitotic drugs, the investigated specimen must exhibit proliferating features, which is given only in a very poor manner blood samples, as peripheral blood cells have typically exited the cell cycle. However cells in the dermis still proliferate, albeit to a small percentage. Therefore, considering these issues, we set out to develop a method to analyse drug effects in skin biopsies. Traditionally, most analyses of skin biopsies have relied on immunohistochemistry (IHC) studies. However, the quantification of such results is time-consuming and error-prone. Western Blot analyses are easier to quantify, but require a considerable amount of protein lysate of sufficient concentration. We developed a protocol that reproducibly allows the detection and quantification of phosphorylated histone H3 in Western Blots from a single half of a skin biopsy. For normalization, the total amount of histone H3 present in the lysate is determined. The other half of the skin biopsy may be used for IHC analysis of phosphorylated histone H3, allowing the comparison to other studies relying solely on IHC. We will present data on the measurement of phosphorylated histone H3 via Western Blots and IHC from skin biopsies of healthy donors. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of