Cytokeratin 6 identifies basal-like subtypes of pancreatic ductal adenocarcinoma with decreased survival

J Cancer Res Clin Oncol. 2023 Aug;149(10):7539-7546. doi: 10.1007/s00432-023-04702-5. Epub 2023 Mar 27.

Abstract

Purpose: Rising incidence of pancreatic ductal adenocarcinoma (PDAC) bind with insufficient therapy options showcases a great medical challenge. Further biomarkers are required to identify patients, who will benefit from more aggressive therapy.

Methods: 320 patients were included by the PANCALYZE study group. Cytokeratin 6 (CK6) immunohistochemical staining as a putative marker for the basal-like subtype of PDAC was performed. The correlation between CK6 expression patterns and survival data, as well as various markers of the (inflammatory) tumor microenvironment, were analyzed.

Results: We divided the study population based on the expression pattern of CK6. Patients with a high CK6 tumor expression had a significantly shorter survival (p = 0.013), confirmed in a multivariate cox regression model. CK6-expression is an independent marker for a decreased overall survival (HR = 1.655, 95% CI 1.158-2.365, p = 0.006). In addition, the CK6-positive tumors showed significantly less plasma cell infiltration and more cancer-associated fibroblasts (CAFs) expressing Periostin and SMA.

Conclusions: CK6 could be considered as an independent biomarker for a shorter overall survival. CK6 is a clinically easily accessible biomarker for the identification of the basal-like subtype of PDAC. Therefore, it could be taken into consideration in deciding for the more aggressive therapy regimes. Prospectively, studies addressing the chemosensitive characteristics of this subtype are required.

Keywords: Basal-like subtype; Cytokeratin 6; Pancreatic ductal adenocarcinoma; Personalized medicine.

MeSH terms

  • Biomarkers, Tumor / metabolism
  • Carcinoma, Pancreatic Ductal* / pathology
  • Humans
  • Keratin-6
  • Pancreatic Neoplasms* / pathology
  • Prognosis
  • Tumor Microenvironment

Substances

  • Keratin-6
  • Biomarkers, Tumor