Anna Shangguan1, Na Shang2, Matteo Figini2, Liang Pan3, Jia Yang2, Quanhong Ma2, Su Hu4, Aydin Eresen2, Chong Sun5, Bin Wang6, Yuri Velichko7, Vahid Yaghmai7, Zhuoli Zhang8. 1. Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA; Medical Student Training Program, Northwestern University, Chicago, Illinois, USA. 2. Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA. 3. Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA; Department of Radiology, The Third Affiliated Hospital of Suzhou University, Changzhou, Jiangsu, China. 4. Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA; Department of Radiology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China. 5. Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA; Department of Orthopaedics, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China. 6. Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA; Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangdong Provincial Engineering Technology Research Center of Minimally Invasive Surgery, Guangzhou, China. 7. Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA; Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, Illinois, USA. 8. Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA; Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, Illinois, USA. Electronic address: zhuoli-zhang@northwestern.edu.
Abstract
PURPOSE: Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related deaths with high recurrence after surgery due to a paucity of effective post-surgical adjuvant treatments. DC vaccines can activate multiple anti-tumor immune responses but have not been explored for post-surgery PDAC recurrence. Intraperitoneal (IP) delivery may allow increased DC vaccine dosage and migration to lymph nodes. Here, we investigated the role of prophylactic DC vaccination controlling PDAC tumor growth with IP delivery as an administration route for DC vaccination. METHODS: DC vaccines were generated using ex vivo differentiation and maturation of bone marrow-derived precursors. Twenty mice were divided into four groups (n = 5) and treated with DC vaccines, unpulsed mature DCs, Panc02 lysates or no treatment. After tumor induction, mice underwent three magnetic resonance imaging scans to track tumor growth. Apparent diffusion coefficient (ADC), a quantitative magnetic resonance imaging measurement of tumor microstructure, was calculated. Survival was tracked. Tumor tissue was collected after death and stained with hematoxylin and eosin, Masson's trichrome, terminal deoxynucleotidyl transferase dUTP nick end labeling and anti-CD8 stains for histology. RESULTS: DC-vaccinated mice demonstrated stronger anti-tumor cytotoxicity compared with control groups on lactate dehydrogenase assay. DC vaccine mice also demonstrated decreased tumor volume, prolonged survival and increased ΔADC compared with control groups. On histology, the DC vaccine group had increased apoptosis, increased CD8+ T cells and decreased collagen. ΔADC negatively correlated with % collagen in tumor tissues. DISCUSSION: Prophylactic DC vaccination may inhibit PDAC tumor growth during recurrence and prolong survival. ΔADC may be a potential imaging biomarker that correlates with tumor histological features.
PURPOSE:Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related deaths with high recurrence after surgery due to a paucity of effective post-surgical adjuvant treatments. DC vaccines can activate multiple anti-tumor immune responses but have not been explored for post-surgery PDAC recurrence. Intraperitoneal (IP) delivery may allow increased DC vaccine dosage and migration to lymph nodes. Here, we investigated the role of prophylactic DC vaccination controlling PDACtumor growth with IP delivery as an administration route for DC vaccination. METHODS: DC vaccines were generated using ex vivo differentiation and maturation of bone marrow-derived precursors. Twenty mice were divided into four groups (n = 5) and treated with DC vaccines, unpulsed mature DCs, Panc02 lysates or no treatment. After tumor induction, mice underwent three magnetic resonance imaging scans to track tumor growth. Apparent diffusion coefficient (ADC), a quantitative magnetic resonance imaging measurement of tumor microstructure, was calculated. Survival was tracked. Tumor tissue was collected after death and stained with hematoxylin and eosin, Masson's trichrome, terminal deoxynucleotidyl transferase dUTP nick end labeling and anti-CD8 stains for histology. RESULTS: DC-vaccinated mice demonstrated stronger anti-tumor cytotoxicity compared with control groups on lactate dehydrogenase assay. DC vaccine mice also demonstrated decreased tumor volume, prolonged survival and increased ΔADC compared with control groups. On histology, the DC vaccine group had increased apoptosis, increased CD8+ T cells and decreased collagen. ΔADC negatively correlated with % collagen in tumor tissues. DISCUSSION: Prophylactic DC vaccination may inhibit PDACtumor growth during recurrence and prolong survival. ΔADC may be a potential imaging biomarker that correlates with tumor histological features.