Many studies have showed the functional GJIC-dependent enhancing effects of Cx43, Cx37, Cx32, and Cx26 on the toxicity of chemotherapeutic agents in cancer cells.21, 32, 33, 34 However, the GJIC-independent effects of Cxs cannot be discarded, as increasing evidences point the facilitating roles of Cxs in tumorigenesis and cancer chemoresistance via GJIC-independent manner. The gene discussed is GJB2; the disease is cancer.