In summary, our results revealed that in an SND1-dependent manner, knockdown of circ_0004087 suppresses the transactivation of MYB and reduces BUB1 expression, further disrupts the DTX resistance of PCa cells by breaking down the error correction mechanism of mitosis, suggesting that circ_0004087 is a potential therapeutic target to improve DTX chemosensitivity in prostate cancer (Fig. 9A). Here, BUB1 is linked to prostate cancer.