Fig. 3.

Ability of ESCC cells to form new colonies after ATP treatment. The clonogenic assay was performed to evaluate the interference of ATP on cell proliferation after 10 days of treatment as described in “Material and Methods.” Evaluation of polyclonal cell population (a) and quantification of colony number (b). Each column represents the mean ± SEM, *p < 0.05, **p < 0.01, and ***p < 0.001, and the results were established in relation to control cells. The experiments were performed in triplicate