Such a contribution of secreted HSP90α to cancer stemness-related processes was dependent on and causally linked to transcription factor 12 (TCF12): Extracellular HSP90α triggers the CD91/IKK/NFκB signaling cascade, which results in TCF12 expression, while the latter is required for HSP90α secretion and EMT [108]. Here, HSP90AA1 is linked to cancer.