In human head and neck squamous carcinoma cells, prostate cancer cells, and laryngeal cancer cells, blocking of stat3 by decoy oligonucleotides or antisense oligonucleotides or siRNA abrogates the production of transforming growth factor (TGF) and suppresses the oncogenic growth of these cells.15 Furthermore, some studies have revealed some apoptosis-related genes, such as Bcl-xL, C-myc and cyclin D1, etc, that are involved in the STAT3 blockage induced suppression of cancer cell growth. Here, STAT3 is linked to prostate cancer.