Laser scanning analysis of cell-cell communication in cultured human prostate tumor cells

OBJECTIVE: To investigate gap-junctional intercellular communication (GJIC) in LNCaP and DU145 human prostate cancer cells. STUDY DESIGN: Normal rat liver F344 (WB1) cells were used as positive contr ols. Functional GJIC was inspected using either the scrape-loading/dye tran sfer (SL/DT) method or fluorescence recovery after photobleaching (FRAP) an alysis. In the former, GJIC activity was expressed as a measure of the exte nt of diffusion of Lucifer Yellow after cell monolayers were scraped using a surgical blade and exposed to dye for a few minutes at room temperature. In the latter, cells were incubated for 15 minutes at 37 degrees C with 5,6 -carboxyfluorescein diacetate dye and the dye transfer visualized by photob leaching individual cells with a 488-nm laser and monitoring the recovery o f fluorescence using a laser cytometer. RESULTS: The preliminary results obtained indicate that neither LNCaP nov D U145 cells have functional GJIC, while, as expected, WB1 cells show unimpai red GJIC activity. Equivalent results were consistently obtained using eith er SL/DT or the FRAP approach. However, using FRAP analysis, DU145 cells on ly showed weak recovery of fluorescence after a total observation interval of 25 minutes. CONCLUSION: The present data, though preliminary, suggest that disruption o f GJIC may play a role in development of malignancy in the human prostate.