Intrinsic drug resistance of pancreatic ductal adenocarcinoma (PDAC) warrants studies using models that are more clinically relevant for identifying novel resistance mechanisms as well as for drug development. Tumor spheroids (TS) mimic in vivo tumor conditions associated with multicellular resistance and represent a promising model for efficient drug screening, however, pancreatic cancer cells often fail to form spheroids using conventional methods such as liquid overlay. This study describes the induction of TS of human pancreatic cancer cells (Panc-1, Aspc-1, Capan-2) in concave polydimethylsiloxane (PDMS) microwell plates and evaluation of their usefulness as an anticancer efficacy test model. All three cell lines showed TS formation with varying degree of necrosis inside TS. Among these, Panc-1 spheroid with spherical morphology, a rather rough surface, and unique adhesion structures were successfully produced with no notable necrosis in concave microwell plates. Panc-1 TS contained growth factors or enzymes such as TGF-β1, CTGF, and MT1-MMP, and extracellular matrix proteins such as collagen type I, fibronectin, and laminin. Panc-1 cells grown as TS showed changes in stem cell populations and in expression levels of miRNAs that may play roles in chemoresistance. Visualization of drug penetration and detection of viability indicators, such as Ki-67 and MitoSOX, were optimized for TS for quantitative analysis. Water-soluble tetrazolium (MTS) and acid phosphatase (APH) assays were also successfully optimized. Overall, we demonstrated that concave PDMS microwell plates are a novel platform for preparation of TS of weakly aggregating cells and that Panc-1 spheroids may represent a novel three-dimensional model for anti-pancreatic cancer drug screening.

Background/Aims: Constipation is a common gastrointestinal disorder. Prucalopride is a dihydrobenzofurancarboxamide derivative with gastrointestinal prokinetic activities and is recommended as an appropriate choice in patients unresponsive to laxatives. This study assessed the safety and efficacy of prucalopride in Korean patients with chronic constipation, in whom laxatives were ineffective. Methods: This prospective, non-interventional post-marketing surveillance of prucalopride was conducted from 2012 to 2018 at 28 hospitals in Korea. Adults who received prucalopride for the symptomatic treatment of chronic constipation were included. The patients received 2 mg of prucalopride once daily or 1 mg once daily in patients older than 65 years. The baseline characteristics, adverse events (AEs), and seven-point scale of Clinical Global Impression-Improvement were collected. Results: Of 601 patients, 67.7% were female, and the mean age was 62.3 years. Three hundred patients (49.9%) were older than 65 years. At the baseline, 70.0% of patients reported less than two instances of spontaneous complete bowel movements per week. AEs were reported in 107 patients (17.7%), including headache (3.2%) and diarrhea (2.8%). Seven serious AEs (SAEs) were reported in five patients (0.8%). The SAEs were resolved without complications; there were no cases of death. All SAEs were assessed as 'unlikely' causality with prucalopride. In 72.7% of patients, chronic constipation was improved by the prucalopride treatment during the study period. Conclusions: This study demonstrated the promising safety and efficacy profile of prucalopride in clinical practice. Thus, prucalopride should be considered in patients with chronic constipation when bowel symptoms are refractory to simple laxatives.