TGM2 and breast neoplasm: In GSE26910 dataset, composed of 6 matched tumor and normal stroma laser-microdissected from breast tumors, we observed an up-regulation of TGM2 in the tumor-associated stroma (Figure S2B), again suggesting that TGM2 expression could be associated with the presence of a stimulation exerted by tumor cells similar to the one reproduced in our in vitro model.