ABCG2 and cancer: In this type of cancer, improved OS was correlated with high ABCG2 expression only in early-stage cancer disease (stage 1) (p < 0.001, Figure S4A), in high-grade tumors (G3) (p = 0.0.340, Figure S4F), in patients who never smoked (p = 0.0220, Figure S4K), and regardless of gender (p = 0.0400, p = 0.0021, Figure S4I,J).