The use of IDO/TDO-IN-2, a dual inhibitor targeting IDO3 and TDO1, reversed the inhibition of NK cell-mediated antibody-dependent cytotoxicity (ADCC) by oncolytic-positive cancer-associated fibroblasts and helped to attenuate Trastuzumab resistance in HER2 positive breast cancer [106]. The gene discussed is IDO1; the disease is cancer.