P4HA1 and breast cancer: The highest mRNA expressions of P4HA1 were found sequentially in the various stages of the BC, Stage 1 (p = 8.8817E-16) <Stage 3 (p = 1.670441E-12) <Stage 2 (p = 1.62447E-12) <Stage 4 (p = 1.31617E-03) (Figure 2D), and the highest mRNA expressions of P4HA1 were similarly found in-between the age group of 40–80 (p = 1.62447E-12) and marginally lower in age <80 (p = 3.9105E-08) than the >40 (p = 6.3915E-04) age group (Figure 2F).