DNAJB1 and cancer: However, mutp53 is less susceptible to degradation leading to increased protein levels.153 The mechanism of how mutp53 is stabilized is still not fully known, however the heat shock protein complex HSP40/HSP70/HSP90 plays a major role in the stabilization of mutp53.156 HSP40, a co-chaperone of HSP70, is a first line defense detecting misfolded proteins and its various classes play various roles in stabilizing mutp53 protein in cancer.