Cyr61: a potential therapeutic target for prostate cancer

early stage PCa or prostatic intraepithelial neoplasia and is a useful tissue biomarker for the detection of PCa in biopsy samples. Moreover, Schmitz et al.2 confirmed that Cyr61 can affect the integrin function in cell migration, and insist on the issue of tumorigenicity of Cyr61 and add novel insight into the Cyr61-dependency of PC-3 cells. Previous data suggested that Cyr61 acts as a tumor-promoting factor and a key regulator in cancer progression.9 Overproduction of Cyr61 was high in PC-3 cells through activation of the PI3K/Akt signaling, while knockdown of Cyr61 expression induces upregulation of proapoptotic molecules. Pharmacologic studies have emerged that zoledronic acid (ZOL) is an aminobisphosphonate able to have an antitumor effect on hormone-refractory PCa. Marra et al.10 observed the effects of Cyr61 on ZOL-inhibited PC-3 cells. After treating with ZOL, downregulated-Cyr61 potentiated more powerful growth inhibition than control PC3 cells. Besides, downregulation of Cyr61 increased the percentage of cells in S-phase and the effects induced by ZOL on PCa cell motility and invasion. Furthermore, Lee et al.9 have confirmed an antiapoptotic role of Cyr61 protein in PC-3 cells. In summary, based on the study of Terada et al.,1 Schmitz et al.2 and other available data given therapeutic potential for PCa, these findings may suggest a valuable role for Cyr61 in the development of PCa. However, the mechanisms of interaction between them still poor understand. Additional studies are required, not only in animals, but in humans to further illustrate the clear relationship between PCa and Cyr61. Defining the often chief contribution of Cyr61 to PCa and identifying the mechanisms by which they alter the pathogenesis of disease is a rapidly expanding area of study and will add valuable information to our understanding of the kinetics, pathology and biology of PCa.