Glycyrrhizin (GA) is the major bioactive component found in licorice roots of a small leguminous shrub, Glycyrrhiza glabra L. In athymic BALB/c nude mice xenograft with human lung adenocarcinoma A549 cells stably transfected with TxA2 receptor (TPα), GA (135 mg/kg) reduced thromboxane synthase (TxAS) and proliferating cell nuclear antigen (PCNA) expression via suppressing TxA2 pathway (Deng et al., 2017). Here, PCNA is linked to lung adenocarcinoma.