Experiments were conducted to determine the effects of novel anti-neoplastic isochalcones (DJ compounds), on cyclooxyegenase 1 and 2 (COX-1 and COX-2) enzyme expression in androgen receptor dependent human prostate cancer cell line LNCaP. Results from Western blot analysis and cell flow cytometry showed that DJ52 and DJ53 decreased the steady state levels of COX-1 and COX-2 protein levels in a dose dependent manner. In addition, DJ52 and DJ53 decreased the levels of epidermal growth factor (EGF) in LNCaP cells. In this study, we report that novel isochalcones decreased COX-1, COX-2 and EGF levels as well as LNCaP cellular growth in a dose responsive manner. Our findings indicate that relative decreases in COX-1, COX-2 and EGF expressions might serve as indicators of tumor growth inhibition in prostate neoplasms.