PGG also exerts an anti-invasive effect by suppressing the epidermal growth factor receptor (EGFR)/c-Jun N-terminal kinases (JNK) pathway and controlling matrix metalloproteinase-9 (MMP-9) expression, resulting in suppresses bone metastasis in nude mice treated with an intratibial injection of PC-3 prostate cancer cells [17]. This evidence concerns the gene MMP9 and prostate cancer.