Moreover, since NQO1 and multiple keynotes involved in de-novo NAD+ synthesis (such as LAT1and IDO) are overexpressed in a number of cancers, our study suggests that the combinatory therapy with NQO1 activating agents and the inhibitor of de-novo NAD+ synthesis may be a promising strategy for the therapy of NSCLC and other cancers. Here, IDO1 is linked to cancer.