Increased SPARC expression is associated with neoadjuvant therapy in resectable pancreatic ductal adenocarcinoma

Christopher Hartley; Daniel Rowan; Xiuxu Chen; Luisa Gomez-Arellano; Anna Marie West; Kiyoko Oshima; Alexander Craig Mackinnon

doi:10.1016/j.plabm.2020.e00171

Increased SPARC expression is associated with neoadjuvant therapy in resectable pancreatic ductal adenocarcinoma

Pract Lab Med. 2020 May 29:21:e00171. doi: 10.1016/j.plabm.2020.e00171. eCollection 2020 Aug.

Authors

Christopher Hartley¹, Daniel Rowan¹, Xiuxu Chen¹, Luisa Gomez-Arellano¹, Anna Marie West¹, Kiyoko Oshima¹, Alexander Craig Mackinnon¹

Affiliation

¹ Medical College of Wisconsin, #University of Alabama at Birmingham, United States.

Abstract

Secreted Protein Acid and Rich in Cysteine (SPARC) is an extracellular glycoprotein secreted by fibroblasts and osteoblasts in normal tissues. SPARC overexpression occurs in multiple tumors including pancreatic ductal adenocarcinoma (PDAC) and may predict favorable response to nab-paclitaxel. The prognostic significance of SPARC expression in PDAC is unclear - some reports indicate SPARC overexpression associates with poor outcomes and others find no correlation. Considering neoadjuvant therapy enhances the stromal fibrosis of PDAC and taking into account that SPARC is a component of PDAC stromal fibrosis, we hypothesized that SPARC expression would be greater in neoadjuvant-treated versus treatment-naive PDAC. Quantitative immunohistochemistry was used to measure SPARC expression in resected PDAC in 74 cases of neoadjuvant treated PDAC and 95 cases of treatment-naïve PDAC. SPARC expression was increased 54% in neoadjuvant treated PDAC compared to treatment-naïve PDAC. These data indicate that increased SPARC expression correlates with neoadjuvant therapy in PDAC.

Keywords: Adjuvant therapy; Digital image analysis; Immunohistochemistry; Neoadjuvant therapy; Pancreatic cancer; SPARC.