STAT3 and breast cancer: STAT3/p-STAT3 expression was higher in breast cancer tissue than in normal ones (OR = 7.48, 95% CI = 5.64–9.94), in highly differentiated breast cancer tissue than in lowly differentiated cancer tissues (OR = 2.13, 95% CI = 1.53–2.98), in III/IV stage breast cancer than in I/II stage breast cancer (OR = 3.58, 95% CI = 2.44–5.25), and in tissue with lymphatic metastasis than in normal tissues (OR = 3.72, 95% CI = 2.59–5.35), respectively.