Pancreatic Cancer Xenograft Model

The pancreatic ductal adenocarcinoma cell line derived from spontaneous tumours in a Kras^LSL-G12D;Trp53^LSL-R172H;Pdx1-Cre mouse model was a kind gift from R. Kalluri (MD Anderson Cancer Center)^{79 (link)}. Either 5.0 × 10⁵ or 3.5 × 10⁵Kras^LSL-G12D;Trp53^LSL-R172H;Pdx1-Cre cells in 100 μl PBS were injected subcutaneously into the right flank of 6- to 8-week-old C57BL/6J or nude mice, respectively. Within 1 week following tumour cell implantation, mice with similar tumour volumes and body weights were randomized into different groups of anti-tumour treatment, DMXAA (12.5 mg kg⁻¹ body weight diluted in 100 μl PBS; MedChemExpress) or DMXAA- or mock-stimulated macrophage secretomes (0.5 ml; 1 million macrophages) intraperitoneally twice at days 7 and 10. For heat inactivation, secretomes were heated at 80 °C for 20 min before injections. Tumour growth was monitored and tumour volumes were calculated as (length × width²)/2. A tumour burden of <10% of body weight or a tumour size of <20 mm in any dimension was permitted by the Ethics Committee of the First Affiliated Hospital of the Zhejiang University School of Medicine. The maximal tumour size/burden was not exceeded in this study.