STAT3 and cancer: Meanwhile, the expression of pStat3 was confirmed to be significantly correlated with tumour stage, differentiation and presence of lymph node metastasis.8, 33 Moreover, recent published in vivo studies have shown that Stat3 knockdown reduces ovarian tumour growth and metastatic potential, revealing that Stat3 activation is required by ovarian cancer progression and metastasis.34, 35 Infiltration of surrounding tissues and distant metastasis are two crucial malignant tumour hallmarks, evidently affecting the prognosis and therapy success rate of cases.