Many studies have reported on the niclosamide enhances cytotoxicity on various cancers, including oral cancer, lung cancer, colon, thyroid, cervix, ovarian, kidney, and prostate cancers, via STAT3, EGFR/PI3K/Akt, RANKL Wnt, mTOR, HIF‐1α/VEGF, Ras, c‐myc, and Notch signal pathways and mitochondria dysfunction.11, 12, 13, 14, 26, 27, 28, 29, 30, 31, 32, 33 Cancer cell upregulates other important downstream genes such as STAT3, which contributes to cell proliferation, cell survival, and angiogenesis in many cancers. Here, STAT3 is linked to prostate cancer.