Li et al.  identified a highly tumourigenic sub-population
of pancreatic cancer cells expressing the cell surface markers CD44, CD24, and epithelial-specific antigen (ESA) capable of self-renewal and increased tumourigenic potential. The identification of pancreatic cancer stem cells has many significant implications for the treatment of pancreatic Napabucasin chemical structure cancer. TSA HDAC solubility dmso Therefore, in this study, we isolated clonal isogenic sub-populations, derived from the original pancreatic cancer cell line, MiaPaCa-2. Clone #3 and Clone #8 exhibit identical genetic fingerprints with different malignancy-related phenotypes. We examine how altered integrin expression including β1, α5 and α6 affects invasion, motility, adhesion and anoikis using RNAi. Furthermore, the role of integrins in the aggressive invasive phenotype, which correlates with in vitro malignant transformation in this pancreatic cancer cell line model, could help to define an invasion/metastatic-related model for pancreatic cancer. Methods Cell lines The
human pancreatic cell line MiaPaCa-2 see more was obtained from the European Collection and Cell Cultures (ECACC, UK). Clone #3 and Clone #8 were obtained by limitation dilution cloning in this laboratory, adapted from . The parental cell line was diluted to a concentration of 3 cells/ml and 100 μl plated onto each well of a 96-well plate. After 24 hours each well was studied for single cells, which were allowed to grow into colonies. Once confluence was achieved, cells were transferred to a T25-T75 cm3 flask within 2 weeks. The colonies were then screened by invasion assay to assess their invasive abilities. Cells were maintained in a humidified atmosphere containing
5% CO2 at 37°C in Dulbecco’s modified Eagles medium (DMEM) supplemented with 5% foetal bovine serum (Sigma-Aldrich). Antibiotics were not used in the growth media. All cell lines were free from Mycoplasma as tested with the indirect Hoechst staining method. Invasion and Motility assays Invasion assays were performed using an adapted method . Matrigel was diluted to 1 mg/ml in serum free DMEM. Laminin, fibronectin and collagen type IV was diluted to 25 μg/ml in PBS and collagen type I to 10 μg/ml. 100 μl of ECM protein was placed into each insert (Falcon) (8.0 μm pore size), in a 24-well plate (Costar). The ECM coated inserts were incubated 2-hydroxyphytanoyl-CoA lyase overnight at 4°C. The following day, the ECM was allowed polymerise at 37°C for 1 hr. The inserts were then washed with serum-free DMEM, 100 μl of complete DMEM was added to the wells and 1 × 105/100 μl cells were then seeded onto the insert. 500 μl of complete DMEM was added into the underside of the well. After 24 hours incubation, the inside of the insert was wiped with a wet cotton swab. The under surface was gently rinsed with PBS and stained with 0.25% crystal violet for 10 minutes, rinsed again with sterile water and allowed to dry.