In an attempt to explain the mechanisms underlying the synergistic interaction between CLFF and chemotherapeutic agents, we hypothesized that CLFF might affect the expression of the investigated chemotherapeutic agent resistance-related genes, i.e. excision repair cross-complementing (ERCC1), thymidylate synthase (TS), class III β-tubulin (β-tubulin III) and tau, in gastric cancers, influencing sensitivity to those drugs. The gene discussed is ERCC1; the disease is gastric cancer.