PCNA and pancreatic neoplasm: Consist of these findings, western blotting assay also showed erlotinib inhibited the activation of EGFR (represented by the desecration of p-EGFR) and HSF1 (represented by the desecration of HSP70), and reduced the proliferation marker PCNA (Fig. 6e), which revealed the core role of EGFR on modulating pancreatic cancer initiation and HSF1 activation in vivo.