Combined treatment of pancreatic cancer xenograft with 90Y-ITGA6B4-mediated radioimmunotherapy and PI3K/m TOR inhibitor

作     者：Winn Aung Atsushi B Tsuji Hitomi Sudo Aya Sugyo Yoshinori Ukai Katsushi Kouda Yoshikazu Kurosawa Takako Furukawa Tsuneo Saga Tatsuya Higashi 

作者机构：Department of Molecular Imaging and TheranosticsNational Institute of Radiological SciencesNational Institutes for Quantum and Radiological Science and Technology(QST-NIRS) Perseus Proteomics Inc. Innovation Center for Advanced MedicineFujita Health University Department of Radiological and Medical Laboratory SciencesNagoya University Graduate School of Medicine Department of Diagnostic RadiologyKyoto University Hospital 

出 版 物：《World Journal of Gastroenterology》 (世界胃肠病学杂志（英文版）)

年 卷 期：2017年第23卷第42期

页      面：7551-7562页

核心收录：

学科分类：1002[医学-临床医学] 100214[医学-肿瘤学] 10[医学] 

基　　金：Supported by(partially)a Grant-in-Aid for Scientific Research(C)from the Ministry of Education Culture Sports Science and Technology Japan No.17K10460 to Aung W 

主　　题：Radioimmunotherapy Pancreatic cancer Anti-integrin α6β4 antibody Yttrium-90 NVP-BEZ235 

摘      要：AIM To investigate the therapeutic effect of combined integrin α6β4-targeted radioimmunotherapy(RIT) and PI3 K/m TOR inhibitor BEZ235 in a pancreatic cancer *** Phosphorylation of Akt, m TOR, the downstream effectors eukaryotic initiation factor 4 E binding protein 1(4 EBP1) and S6 ribosomal protein(S6) were evaluated in Bx PC-3 human pancreatic cancer cells treated with Yttrium-^(90)(^(90) Y) labeled anti-integrin α6β4 antibody(ITGA6 B4) and BEZ235 by western blotting. The cytotoxic effect of BEZ235 was investigated using a colony formation assay. Therapeutic efficacy enhancement by oral BEZ235 administration was assessed using mice bearing Bx PC-3 xenograft tumors. Tumor volume measurements and immunohistochemical analyses(cell proliferation marker Ki-67, DNA damage marker p-H2 AX and p-4 EBP1 staining) of tumors were performed for evaluation of combined treatment with ^(90) Y-ITGA6 B4 plus BEZ235, or each arm *** We found that phosphorylation of Akt(p-Akt), 4 EBP1(p-4 EBP1) and S6(p-S6) was inhibited by BEZ235. Colony formation in Bx PC-3 cells was additively suppressed by the combination of ^(90) Y-ITGA6 B4 and BEZ235. Pretreatment with BEZ235 before ^(90) Y-ITGA6 B4 exposure resulted in significant reduction of cells plating efficiency(PE)(0.54 ± 0.11 vs 2.81 ± 0.14 with 185 k Bq/m L ^(90) Y-ITGA6 B4 exposure, P 0.01; 0.39 ± 0.08 vs 1.88 ± 0.09 with 370 k Bq/m L ^(90) Y-ITGA6 B4 exposure, P 0.01) when 5 × 10~3 cells per dish were plated. In vivo, the combined treatment with ^(90) Y-ITGA6 B4 plus BEZ235 enhanced the inhibition of tumor growth and statistically significant differences of relative tumor volume were observed for 27 d after the treatment start date when compared with the ^(90) Y-ITGA6 B4 single injection treatment(1.03 ± 0.38 vs 1.5 ± 0.15 at Day 27, P 0.05), and for 41 d when compared with the BEZ235 treatment alone(1.8 ± 0.7 vs 3.14 ± 1.19 at Day 41, P 0.05). Tumors from treatment groups showed reduction in volumes, dec