IDO/Tubulin-IN-2 (HT2) is a powerful inhibitor of both TDO and tubulin. This compound demonstrates significant efficacy against various cancer cell lines, including U87, HepG2, A549, HCT-116, and LO2, with respective IC50 values of 0.43, 0.036, 0.041, 0.095, and 1.04 μM. Additionally, IDO/Tubulin-IN-2 markedly enhances antitumor activity [1].

IDO/Tubulin-IN-2 (HT2) (0-50 μM, 4 h) exhibits potent cytotoxicity, with IC50 values ranging from 0.036 to 0.43 μM against various cancer cell lines [1]. At a concentration of 0.1 μM over 24 h, it predominantly arrests the cell cycle of HepG2 cells in the G2 phase [1], induces apoptosis [1], and significantly promotes proteolytic cleavage of PARP as well as up-regulates caspase-3 expression [1]. Additionally, at 0.05 μM, IDO/Tubulin-IN-2 progressively reduces TDO mRNA expression levels in a time-dependent manner over 24, 48, and 72 h [1]. After 2 days, it augments T-cell activation and proliferation, thereby enhancing the immune response [1].

IDO/Tubulin-IN-2 (HT2), administered intravenously at a dosage of 30 mg/kg daily for 21 days, considerably suppresses tumor proliferation [1]. Additionally, when given for 29 days using the same dosage and route, it effectively enhances antitumor immunity, thereby augmenting the therapeutic effectiveness against tumors [1].