Sw480

The human CRC cell lines DLD1, RKO, SW480 and LS513 were purchased from the European Collection of Cell Cultures (Sigma-Aldrich, Munich, Germany) or the American Type Culture Collection (LGC Standards, Wesel, Germany), respectively. DLD1 cells homozygously harboring the hypomorphic Seckel mutation (ATR^s/s) have been described previously [14 , 23 (link), 24 (link)]. This mutation causes a strongly reduced but not absent ATR protein expression without significant impairment of cell proliferation or survival [24 (link)]. All cell lines were maintained in Dulbecco's modified Eagle's medium (DMEM) supplemented with 10% fetal calf serum and 1% penicillin-streptomycin (PAA, Coelbe, Germany) and incubated at 37°C and 5% CO_2.

The paired colon cancer cell lines SW480 (ECACC: 87092801, colon adenocarcinoma) and SW620 (ECACC: 87051203, lymph node metastasis) were purchased from the European Collection of Cell Cultures (ECACC) and maintained in L-15 Medium with GlutaMAX™ supplemented with 10% [v/v] fetal calf serum (Lonza) and 100 U/ml Penicillin, 100 μg/ml Streptomycin and 12.5 μg/ml Amphotericin at 37 °C in a humidified incubator without the introduction of CO₂.

COLO-205, SW48, SW480, LS180, LS174-T, HT-29, T84 and LoVo cells were purchased from the European Collection of Cell Cultures (ECACC). Cells in culture were maintained as a subconfluent monolayer in Dulbecco's Modified Eagle's medium supplied with non-essential amino acids (LS180 and LS174-T), Dulbecco's modified Eagle's medium-F12 nutrient mixture (T84), McCoy 5-A medium (HT-29), L15 Leivobitz medium (SW48 and SW480), Nutrient Mixture F12 HAM (LoVo) and RPMI 1640 (COLO-205) purchased from Sigma. Each cell line was grown under identical conditions, and cell culture medium supplements were provided according to the manufacturer's instructions. To ectopically overexpress c-Src kinase protein, subconfluent SW480 and T84 cells were transfected with 0.4 μg of pBABE-puro expression plasmid carrying cDNA from a c-Src gene. Stable clones of the T84 cell line were selected in F12/DMEM medium supplied with 0.5 μg of puromycin for 3 weeks. In the same way, stable clones of the SW480 cell line were selected in L15 Leivobitz medium supplied with 0.5 μg of puromycin. As a control, subconfluent SW480 and T84 cells were transfected with 0.4 μg of DNA containing an empty pBABE-puro expression plasmid. Positive clones were selected for protein expression measured by Western blotting. The entire set of transfected clones was used as a stable pool for transfection.

DLD-1, LOVO, HT29, SW480, SW1116, WiDR, and HCT116 cells were purchased from the European Collection of Cell Cultures (Salisbury, UK), and SW620 cells were purchased from the American Type Culture Collection (Manassas, VA, USA). COLO205, HCT-15, and LS174T cells were provided by the Cell Resource Center for Biomedical Research, Tohoku University (Sendai, Japan). COLO201 cells were provided by the Japanese Collection of Research Bioresource (Tokyo, Japan), and COLO-320 cells were provided by RIKEN Bio-Resource (Tsukuba, Japan). The cells were cultured in RPMI 1640 medium supplemented with 10% fetal bovine serum (FBS) and 2 mM glutamine at 37°C in humidified air containing 5% CO₂. Cells were used when in the exponential growth phase.