Evaluation of Stem Cell Marker Gene Expression in Canine Prostate Carcinoma- and Prostate Cyst-derived Cell Lines

Background/Aim: In human prostate cancer cells with a stem cell-like character (cancer stem cells, CSC) are considered to play a major role in disease development, progression and relapse. Aim of the study was to evaluate if similar cells are present and active in canine prostate cancer providing a naturally-occurring mammalian model for the development of therapeutic approaches targeting CSC. Materials and Methods: Stem cell marker expression of CD133, CD44, C-KIT, CD34, ITGA6, OCT4, DDX5 and MELK in canine prostate carcinomas and prostate cyst cell lines were screened by Polymerase Chain Reaction (PCR), quantitative Polymerase Chain Reaction (qPCR) and partially analysed by flow cytometry. Results: Marker analyses by PCR and qPCR, revealed a complex expression pattern for the analysed marker genes, providing a characteristic marker pattern for the studied cell lines. Thereby CD44, CD133, ITGA6 and DDX5 showed the most prominent expression in the analysed cell lines. Conclusion: The results revealed a characteristic stem cell marker expression in the analysed cell lines, indicating the presence of CSC in canine prostate cancer. Prostate Cancer is considered the second highest factor of cancer-related death in men in occidental society. Recent published statistics of the American Cancer Society show that one out of six males tends to develop prostate cancer (1). Predictions state that in 2013 approximately 238,590 new cases of prostate cancer will be registered and that 29,720 cases of death are expected (1).