Chemotherapy (CT) is the standard care for advanced pancreatic ductal adenocarcinoma (PDAC); however, with limited efficacy. Hyperthermia (HT) treatment has been suggested as a sensitizer to improve outcomes. However, the direct effect of the HT and CT combination is not fully understood. Therefore, we aim to assess the direct cytotoxic effect of HT in PDAC cells as monotherapy or in combination with chemotherapeutics. Different temperatures (37-, 40.5-, 41-, and 41.5 °C) and durations (6-, 12-, and 24 h) were tested in PDAC cell lines (BxPC-3, Capan-1, Capan-2, PANC-1, and MIA-PaCa-2). Different concentrations of gemcitabine, 5-fluorouracil, and cisplatin were also tested in these conditions. The impact on cell metabolic activity was determined by an MTS assay. Enhancement of chemosensitivity was assessed by a reduction in half-maximal inhibitory concentration ($I{C}_{50}$). HT and chemotherapeutics interactions were classified as antagonistic, additive, or synergistic using the combination index. HT inhibited cell proliferation in a cell type, temperature, and duration-dependent manner. The induction of apoptosis was seen after 6 h of HT treatment, eventually followed by secondary necrosis. The HT and CT combination led to an $I{C}_{50}$ reduction of the tested CT. At 12 h of HT, this effect was between 25 to 90% and reached a 95% reduction at 24 h. The additive or synergistic effect was demonstrated in all cell lines and chemotherapeutics, although, again, this depended on cell type, duration, and temperature. HT is cytotoxic and enhances the therapeutic effectiveness of gemcitabine, 5-fluorouracil, and cisplatin on PDAC cells. This result was further confirmed by the decrease in the expression of RRM2, TS, and ERCC1 in BxPC-3 and Capan-2 cells. These observations warrant further study in specific subsets of PDAC patients to improve their clinical outcomes.

A series of poly(alkylene terephthalate)s was synthesized and the effect of the polymer molar mass and alkyl chain length on the surface properties of spin-coated films was investigated, as well as the endothelial cell adhesion and proliferation.

The chorioallantoic membrane (CAM) model is an increasingly attractive model for the study of human tumors. However, concise techniques for the use of pancreatic ductal adenocarcinoma BxPC-3 xenografts in CAM assays are not yet available. Here, we present a protocol for the induction of BxPC-3 xenograft tumors with high grafting efficiency. We describe steps for embryo incubation, egg handling, and grafting, each of which has been optimized to prevent fungal contamination and minimize mortality.

The chorioallantoic membrane (CAM) model is an underutilised alternative model for the research into tumour xenografts. We demonstrate that in the pancreatic cancer cell lines BxPC-3 and AsPC-1, nucleoside labelling with 5-ethynyl-2'-deoxyuridine (EdU) can be multiplexed with other human cell cycle markers, (e.g., cyclin B1 and Ki-67), particularly when combined with digital image analysis, allowing human versus chicken cell classification. Furthermore, starting from the embryonic day of development 14 (ED14), we observe embryonic cells exhibiting substantial apparent cytoplasmic accumulation of synthetic nucleosides. This was observed for (F-ara-)EdU as well as for the halogenated analogues BrdU and IdU. Characterisation of these cells suggests that they are non-proliferating and possess granules and can be found in the embryonic liver of (non-)grafted embryos, as well as in the CAM itself and within xenograft sections. Importantly, these cells are unlikely to represent activated professional antigen presenting cells as they lack MHC II expression, nor do they express CD41/CD61, ruling out thrombocyte origin. Together, our findings demonstrate that the CAM model constitutes a valuable platform for studying tumour cell cycle dynamics in vivo. However, nucleoside labelling applications beyond ED14 may be confounded by a previously unidentified phenomenon, namely cytoplasmic nucleoside accumulation in certain chicken cells.