In vitro characterization of gap junctional intercellular communication by gap-FRAP technique

Gap junctional intercellular communication (GJIC) has been shown to be involved in the carcinogenesis process. Gap-FRAP (Fluorescence Recovery After Photobleaching) technique could be used to estimate gap junctions functionality and their potential involvement for distinguish normal and cancer cells. In this study, the gap-FRAP technique was used to analyse functional gap-junction-mediated communication for cell lines with different GJIC status. Gap-FRAP data and connexin 43 protein expression decreased for FaDu cancer cell line, in contrast to fibroblast and KB positives cell lines. To check the involvement and functionality of gap junctions in the restitution of the fluorescence after photobleaching, we used a gap junction channel inhibition assay with 18 α-glycyrrhetinic acid. Our results indicate that the degree of gap junctional intercellular communication could be estimated by this technique in vitro.