Purpose Few studies reported about the potential of unphosphorylated heat shock protein
27 (HSP27) and phosphorylated heat shock protein 27 (pHSP27) as a predictor for survival
and gemcitabine resistance in pancreatic ductal adenocarcinoma (PDAC). In this study,
we analysed the expression patterns of pHSP27 and HSP27 in a patient population after
surgery and correlated the immunohistochemical results with clinicopathological data
and long-term outcome of the patients. Methods HSP27 and pHSP27 (Ser-15, Ser-78 and
Ser-82) protein expression were analysed by immunohistochemistry using the immunoreactive
score (IRS) from paraffin-embedded tissue of 106 patients with PDAC who underwent
surgery. Immunohistochemical results were correlated with clinicopathological data,
disease-free (DFS) and overall survival (OS). Results HSP27 expression was significantly
lower in patients with a shorter OS (p = 0.006) and DFS (p < 0.0001). A higher HSP27
expression was associated with a better response to gemcitabine in the resected, non-metastasised
patients group (p = 0.001). Furthermore, HSP27 was downregulated in patients suffering
from metastases at time of surgery (p < 0.001) and in undifferentiated tumours (p
= 0.007). In contrast, pHSP27-Ser15, -Ser78 and -Ser82 were not associated with any
survival data of the study population. Conclusion HSP27 seems to be a strong indicator
for the prediction of OS and DFS. Moreover, HSP27 could play a role in the formation
and migration of liver metastases of PDAC.
