SOX2 Amplification Is a Common Event in Squamous Cell Carcinomas of Different Organ Sites.
Martin Braun, Sebastian Maier, Theresia Wilbertz, Veit Scheble, Markus Reischl, Ralf Mikut, Roopika Menon, Pavel Nikolov, Karen Petersen, Christine Beschorner, Holger Moch, Christoph Kakies, Chris Protzel, Jurgen Bauer, Alex Soltermann, Falko Fend, Anette Staebler, Claudia Lengerke, Sven Perner. University Hospital Bonn, Germany; University Hospital Tuebingen, Germany; Research Center Karlsruhe, Karlsruhe, Germany; University Hospital Zurich, Switzerland; University Hospital Rostock, Germany
Background: Acquired chromosomal aberrations, including gene copy number alterations, are involved in the development and progression of human malignancies. SOX2, a transcription factor-coding gene located at 3q26.33, is known to be recurrently and specifically amplified in squamous cell carcinomas (SCCs) of the lung, the esophagus and the oral cavity. In these organs, the SOX2 protein plays an important role in tumorigenesis and tumor survival. The aim of this study was to determine whether SOX2 amplification is also found in SCCs in other organs commonly affected by this tumor entity.
Design: Applying fluorescence in-situ hybridization, we assessed SCCs of the cervix uteri (n=47), the skin (n=57) and the penis (n=53) for SOX2 copy number alterations. Furthermore, we performed immunohistochemical SOX2 staining to assess SOX2 protein expression. For quantification of protein expression, semi-automated quantitative image analysis software was applied to obtain a continuous spectrum of average brown staining intensity.
Results: We detected SOX2 amplifications in 28% of cervical SCCs, 28% of skin SCCs, and 32% of penile SCCs. Moreover, we found that the SOX2 amplification is significantly associated with an overexpression of the corresponding protein in SCCs (p<0.001).
Conclusions: In our current study we could show that amplification of SOX2 and consequent overexpression of the corresponding protein are not confined to lung SCCs, but that they are found in a considerable subset of SCCs in different organ sites, i.e. the uterine cervix, the skin and the penis. Our data emphasize the need for further elucidation of the role of SOX2 during SCC carcinogenesis and its clinical implications.
Tuesday, March 1, 2011 1:15 PM
Platform Session: Section H, Tuesday Afternoon