The Activation of the CCND1 Promoter by AP-1 and SOX Transcription Factors in PC3 Prostate Cancer Cells Can Be Prevented by Anacardic Acid Analogs

Targeting more than one in nine men before age 70, prostate cancer is the most common type of cancer in men. The increased levels of cyclins, leading to activation of cyclin-dependent kinases (CDKs), play a critical role in the increased proliferation of prostate cancer cells. In this study, the regulation of the cyclin D1 (CCND1) promoter activity by activator protein-1 (AP-1) and SRY-related HMG-box (SOX) transcription factors has been characterized in PC3 prostate cancer cells. The SOX and AP-1 transcription factors can cooperate to activate the CCND1 promoter in PC3 prostate cancer cells and such cooperation can be enhanced by protein kinase A (PKA) and/or mitogen-activated protein kinase kinase 1 (ERK kinase 1, MAP2K1) signaling pathways. Moreover, anacardic acid analogs have been assessed for their potential in reducing cell viability and CCND1 promoter activity. The anacardic acid analog 8b, obtained from γ-resorcylic acid, reduces the viability and proliferation of PC3 cells by decreasing CCND1 promoter activity. The effect of analog 8b, which perfectly mimics the structure of anacardic acid, can be attributed to the inhibition of the activities of the transcription factors SOX and AP-1, which are important regulators of CCND1 promoter activity in prostate cancer cells.