Work

Highly aligned stromal collagen is a negative prognostic factor following pancreatic ductal adenocarcinoma resection

Year: 2016

Type: article

Abstract: // Cole R. Drifka 1, 2, 3 , Agnes G. Loeffler 4 , Kara Mathewson 2 , Adib Keikhosravi 1, 2 , Jens C. Eickhoff 5 , Yuming Liu 2 , Sharon M. Weber 6, 7 , W. John Kao 1, 6, 7, * , Kevin W. Eliceiri 1, 2, 3, 7, * 1 Department of Biomedical Engineering, University of Wisconsin, Madison, WI, USA 2 Laboratory for Optical and Computational Instrumentation, University of Wisconsin, Madison, WI, USA 3 Morgridge Institute for Research, Madison, WI, USA 4 Department of Surgical Pathology, University of Wisconsin, Madison, WI, USA 5 Department of Biostatistics and Medical Informatics, University of Wisconsin, Madison, WI, USA 6 Department of Surgery, University of Wisconsin, Madison, WI, USA 7 University of Wisconsin Carbone Cancer Center, Madison, WI, USA * These authors have contributed equally to this work Correspondence to: Kevin W. Eliceiri, email: [email protected] Keywords: collagen, stroma, microenvironment, quantitative pathology, pancreatic cancer Received: June 07, 2016 Accepted: October 03, 2016 Published: October 20, 2016 ABSTRACT Risk factors for pancreatic ductal adenocarcinoma (PDAC) progression after surgery are unclear, and additional prognostic factors are needed to inform treatment regimens and therapeutic targets. PDAC is characterized by advanced sclerosis of the extracellular matrix, and interactions between cancer cells, fibrillar collagen, and other stromal components play an integral role in progression. Changes in stromal collagen alignment have been shown to modulate cancer cell behavior and have important clinical value in other cancer types, but little is known about its role in PDAC and prognostic value. We hypothesized that the alignment of collagen is associated with PDAC patient survival. To address this, pathology-confirmed tissues from 114 PDAC patients that underwent curative-intent surgery were retrospectively imaged with Second Harmonic Generation (SHG) microscopy, quantified with fiber segmentation algorithms, and correlated to patient survival. The same tissue regions were analyzed for epithelial-to-mesenchymal (EMT), α-SMA, and syndecan-1 using complimentary immunohistostaining and visualization techniques. Significant inter-tumoral variation in collagen alignment was found, and notably high collagen alignment was observed in 12% of the patient cohort. Stratification of patients according to collagen alignment revealed that high alignment is an independent negative factor following PDAC resection ( p = 0.0153, multivariate). We also found that epithelial expression of EMT and the stromal expression of α-SMA and syndecan-1 were positively correlated with collagen alignment. In summary, stromal collagen alignment may provide additional, clinically-relevant information about PDAC tumors and underscores the importance of stroma-cancer interactions.

Source: Oncotarget

DOI: 10.18632/oncotarget.12772