Figure 5.

An ETRB-selective agonist abrogates the effects of BQ788 on melanoma cells. In experiments similar to those illustrated in Fig. 2, S6c (0.1–25 μM) was tested for its effects on A375 cells cultured for 4 days alone or in combination with BQ788 (75 μM). The ETRB agonist stimulates cell growth and blocks the inhibitory effect of the ETRB antagonist. The means of absolute values (n = 3–5) were calculated ± SEM and plotted. P values were calculated by using the Student’s t test and are indicated by ∗ when significantly different (P < 0.05) from controls or in comparison with BQ788 values when the addition of S6c to BQ788 was tested.