HSF1 and breast cancer: Our data presented here, along with observations from our previously published cell model [21] showing that increased HSF1 in oncogenically transformed breast cancer cells promotes a more metastatic phenotype, are consistent with research performed by others who have also shown that elevated cellular stress can accelerate cancer progression [54,55,56,57], and that metastatic tumours show a global increase in stress response compared to normal tissues [58].