STAT3 and cancer: SLs have shown intracellular effects in various cancer cell lines, including inhibition of nuclear factor-κB (NF-κB), inhibition of sarco/endoplasmic reticulum calcium ATPase (SERCA) pump, iron-dependent free radical generation, blocking of the signal transducer and activator of transcription 3 (Stat3), p53 activation, and COX-2 inhibition [2,10,11,12].