Fig. 4
The antitumor activity of MSA-2 plus YM101 in murine models. MSA-2 was administrated orally with a single dose of 50 mg/kg. Mice received equivalent mole Ab treatment on alternate days three times (6.6 mg/kg Isotype; 6.6 mg/kg α-PD-L1; and 8.9 mg/kg YM101). All tumor-carrying mice were randomly divided into six groups: control, MSA-2, α-PD-L1, MSA-2 combined with α-PD-L1, YM101, and MSA-2 combined with YM101 (8 mice per group). Red arrow refers to MSA-2 treatment, and blue arrow refers to antibodies. Tumor volume was measured on alternate days. Mice were euthanatized when tumor volume was larger than 2500 mm3 or when the experiment ended. a–l For the subcutaneous tumors, 1 × 106 CT26, 3 × 106 H22, and 2 × 105 B16 cells were implanted in the right groin of BALB/c and C57BL/6 mice. For the orthotopic breast cancer model, 1 × 105 EMT-6 cells were injected into the right mammary fat pad of BALB/c mice. m For the rechallenge model, BALB/c mice were subcutaneously inoculated with 1 × 106 CT26 cells. Two weeks after the last dose of treatment, the cured or untreated mice were rechallenged with 1 × 106 CT26 cells. CR: complete regression. n–o The overall survival curves of CT26 and H22 models. *p < 0.05 means the significant difference compared to denote the significant difference relative to MSA-2 combined with YM101