STAT5A and cervical cancer: Some reports indicated that STAT5 activation is related to a metabolic shift [16,48]; since we found that the cervical cancer cell line SiHa expressed the IL-2R (Figure 1A) and responded to exogenous IL-2 via STAT5 (Figure 1C and Figure 2), we determined the effect of different IL-2 concentrations (10 and 100 IU/mL) on the NAD+/NADH ratio (Figure 4).