Previous studies have established the oncogenic function of SOX9 in multiple malignancies, including colorectal, breast, and prostate cancers, where its overexpression drives tumor proliferation, invasion, and therapeutic resistance.[32, 33] This study is the first to systematically unveil the molecular mechanism by which SOX9 promotes cancer by activating TIMP1 expression, thereby inhibiting the maturation of DCs and weakening the anti‐tumor immune response. Here, SOX9 is linked to prostate cancer.