Unlike Hsp70, it is not a simple heat shock protein induced by stress, although Hsp27 has name of the same 'Hsp'. Its expression appears not to be a matter of being induced or not upon stress, but appears to be regulated by developmental stages, cell type specificity, intracellular distribution in a specific cell phenotype, and phosphorylation of the Hsp27.
Therefore, I suggest that you have to survey published many articles in all species and all different cell phenotypes, and what state of Hsp27 should I pursue as a result of inductive stress.