ADRB2 and breast cancer: Figure 4e shows that the ADRA2A transcripts were significantly decreased in all BC stages (I, II, III, and IV) when compared to normal tissue. Moreover, the expression of ADRA2C was also downregulated in stages I, II, and II (Figure 4f), with the exception of stage IV. ADRB2 expression was also downregulated for all stages of the disease (Figure 4g). These results suggest that the ADRA2A and ADRB2 transcripts are significantly downregulated in luminal-subtype BC patients, and this occurs independently of the stage of the disease.