Extended Data Fig. 9: Combined blockade of Tgfβr1 and Pdl1 in mouse MRD HCC.
a. Experimental scheme for treatment of oncogene-deprived subcutaneous MRD-bearing mice with control antibody or combination therapy with Tgfbr1 and Pdl1 inhibitors. Treatment is followed by oncogene reactivation to induce tumor recurrence. Kaplan–Meier analysis with log rank test was performed. b. Kaplan–Meier curves show time to recurrence in oncogene-deprived subcutaneous MRD-bearing mice with control antibody (n=4 mice) or combination therapy with Tgfbr1 and Pdl1 inhibitors (n=5 mice). c. Experimental scheme for treatment of oncogene-deprived subcutaneous MRD-bearing mice with control antibody or combination therapy with TgfbrI and anti-Pdl1 inhibitor. Residual tumor niches are then evaluated at the end of treatment. d. Macroscopic and microscopic evaluation of subcutaneous MRD sites shows elimination of residual tumor cells in mice treated with combination therapy with TgfbrI and Pdl1 inhibitors (n=4 mice) than control (n=4 mice). e. Experimental scheme for treatment of oncogene-activated primary MT-HCC with control antibody or combination therapy with TgfbrI and anti-Pdl1 inhibitor. Liver tumor burden is assessed at the end of treatment. f. Quantification of liver tumor burden, gross images, and H&E images of primary MT-HCC treated with control antibody (n=4 mice) or combination therapy with TgfbrI and anti-Pdl1 inhibitor (n=4 mice). Data are presented as mean values +/− SEM. Two-tailed unpaired t-test was used to compare the groups. g. Apoptosis measured by cleaved caspase 3+ cells in liver MRD of MYC-HCC mice treated with control (n=5 mice) versus Tgfbr1 (n=5 mice) or Pdl1 inhibitors (n=5 mice) or combination therapy with Tgfbr1 and Pdl1 inhibitors (n=5 mice). Data are presented as mean values +/− SEM. Two-tailed unpaired t-test was used to compare the groups. h. Flow cytometry quantification of activated CD4 and CD8 T cells which are CD69+/CD44high in MRD of mice treated with control antibody (n=3 mice) or combination therapy with Tgfbr1 and Pdl1 inhibitors (n=3 mice). Bar plots compare the mean between the groups with unpaired t-tests. Data are presented as mean values +/− SEM. Two-tailed unpaired t-test was used to compare the groups. Abbreviations: HCC- hepatocellular carcinoma, PDL1- programmed cell death ligand 1, TGFBr1 transforming growth factor receptor beta 1, H&E-hematoxylin and eosin, Ctrl-control, MRD- Minimal residual disease, MT-HCC- MYC/Twist hepatocellular carcinoma, CD- cluster of differentiation.
