Summary of various post-translational modifications potentially implicated in constitutive activation of HSF1 within cancer cells. Refer to the main text for detailed regulations. Modifications stimulating HSF1 activation are marked in red and modifications inactivating HSF1 are marked in blue. Accordingly, oncoproteins and tumour suppressors are labelled in red and blue, respectively. Proteins displaying both oncogenic and tumour-suppressive roles are labelled in brown. Ac, acetylation; de-phos., de-phosphorylation; K, lysine; polyUb, polyubiquitination; S, serine; T, threonine; Sm, sumoylation.