title: Highly aligned stromal collagen is a negative prognostic factor following pancreatic ductal adenocarcinoma resection.
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.
authors: Department of Biomedical Engineering, University of Wisconsin, Madison, WI, USA.|Laboratory for Optical and Computational Instrumentation, University of Wisconsin, Madison, WI, USA.|Morgridge Institute for Research, Madison, WI, USA.
authors: Cole R
authors: CR
authors: Drifka
authors: Department of Surgical Pathology, University of Wisconsin, Madison, WI, USA.
authors: Agnes G
authors: AG
authors: Loeffler
authors: Laboratory for Optical and Computational Instrumentation, University of Wisconsin, Madison, WI, USA.
authors: Kara
authors: K
authors: Mathewson
authors: Department of Biomedical Engineering, University of Wisconsin, Madison, WI, USA.|Laboratory for Optical and Computational Instrumentation, University of Wisconsin, Madison, WI, USA.
authors: Adib
authors: A
authors: Keikhosravi
authors: Department of Biostatistics and Medical Informatics, University of Wisconsin, Madison, WI, USA.
authors: Jens C
authors: JC
authors: Eickhoff
authors: Laboratory for Optical and Computational Instrumentation, University of Wisconsin, Madison, WI, USA.
authors: Yuming
authors: Y
authors: Liu
authors: Department of Surgery, University of Wisconsin, Madison, WI, USA.|University of Wisconsin Carbone Cancer Center, Madison, WI, USA.
authors: Sharon M
authors: SM
authors: Weber
authors: Department of Biomedical Engineering, University of Wisconsin, Madison, WI, USA.|Department of Surgery, University of Wisconsin, Madison, WI, USA.|University of Wisconsin Carbone Cancer Center, Madison, WI, USA.
authors: W John
authors: WJ
authors: Kao
authors: Department of Biomedical Engineering, University of Wisconsin, Madison, WI, USA.|Laboratory for Optical and Computational Instrumentation, University of Wisconsin, Madison, WI, USA.|Morgridge Institute for Research, Madison, WI, USA.|University of Wisconsin Carbone Cancer Center, Madison, WI, USA.
authors: Kevin W
authors: KW
authors: Eliceiri
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers; D000072645:Cancer-Associated Fibroblasts / Q000378:metabolism / Q000473:pathology; D021441:Carcinoma, Pancreatic Ductal / Q000378:metabolism* / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D003094:Collagen / Q000378:metabolism*; D058750:Epithelial-Mesenchymal Transition / Q000235:genetics; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D010190:Pancreatic Neoplasms / Q000378:metabolism* / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D011379:Prognosis; D017154:Stromal Cells / Q000378:metabolism* / Q000473:pathology; D047368:Tumor Burden; D059016:Tumor Microenvironment
chemical_list: D015415:Biomarkers; D003094:Collagen
keywords: collagen; microenvironment; pancreatic cancer; quantitative pathology; stroma