HJC0152 hydrochloride is a signal transducers and activators of transcription 3 (STAT3) inhibitor. IC50 & Target: STAT3^[1] In Vitro: HJC0152 hydrochloride (compound 11) significantly inhibits cell proliferation and induces apoptosis accompanying cellular morphological changes at concentrations of 1, 5, and 10 μM. Results show that treatment with 10 μM HJC0152 hydrochloride decreases the STAT3 promoter activity in MDA-MB-231 cells by approximately 32%, and increasing the dose of HJC0152 hydrochloride to 20 μM further decreases STAT3 promoter activity by 62% as compare with control. Total STAT3 is reduced after treatment with HJC0152 hydrochloride. HJC0152 hydrochloride induces cleaved caspase-3 and down regulates cyclin D1 in MDA-MB-231 cells^[1]. In Vivo: Mice treated with 7.5 mg/kg of HJC0152 hydrochloride (compound 11) via ip show a better effect in inhibiting tumor growth. The growth of xenograft tumors in mice is significantly reduced by HJC0152 hydrochloride at a dose of 25 mg/kg. It is also noteworthy that HJC0152 hydrochloride does not show significant signs of toxicity at a dose of 75 mg/kg^[1].