Sw620

An HT29 colon cancer cell line was purchased from American Type Culture Collection (Manassas, VA, USA), and SW480 and SW620 colon cancer cell lines were purchased from the Bioresource Collection and Research Center (Hsinchu, Taiwan). All cell lines were maintained in Dulbecco’s Modified Eagle Medium (Gibco, Grand Island, NY, USA) supplemented with 4.5 g/L D-glucose, 10% fetal bovine serum (Gibco), and 1% penicillin/streptomycin (Gibco) in a 37 °C incubator with 5% CO₂.

The CRC cell lines SW1116, SW480, SW620, DLD1, HT29, and CaCO₂ were purchased from the Bioresource Collection and Research Center (BCRC; Hsinchu, Taiwan). SW1116, SW480 and SW620 cells were cultured in Leibovitz L-15 Medium (Life Technologies, Grand Island, NY, USA). HT29 and DLD1 cells were cultured in high-glucose Dulbecco’s modified Eagle’s medium (Invitrogen, Carlsbad, CA, USA). CaCO₂ cells were cultured in Eagle’s minimum essential medium (Invitrogen). Wild type HCT116 (p53^+/+) cells and isogenic p53 null cells (HCT116 (p53^−/−)) were purchased from Horizon Discovery Group (Cambridge, UK) [60 (link)] and cultured in RPMI 1640 medium (Invitrogen). All media were supplemented with 10% fetal bovine serum (FBS; Invitrogen) and antibiotics (100 U mL^-l penicillin and 100 mg mL^-l streptomycin) according to the manufacturer’s instructions.

There were 4 cell lines used in this study including SW480, SW620, HCT 116, and HT-29 cells (Bioresource Collection and Research Center, Hsinchu, Taiwan). SW480 and SW620 cells were established from a same Caucasian male patient with colon adenocarcinoma, and SW480 was isolated from the primary colon tumor site, SW620 was isolated from a lymph node metastasis site. SW480, but not HT-29, secrets granulocyte-macrophage colony-stimulating factor (GM-CSF) that stimulates the proliferation of acute megakaryoblastic leukemia M-07e [21 (link)]. SW480 and SW620 synthesize small quantities of carcinoembryonic antigen (CEA) and belong to Broders' grade 4 cancer [22 (link)]. By Northern blot analysis, the oncogenes c‐myc, H‐ras, K‐ras, N‐ras, myb, fos, and p53 were all expressed in SW480 and SW620 cells [23 (link)]. HT-29 cells were isolated from a Caucasian female patient with colorectal adenocarcinoma (ATCC data). HT-29 and SW480, but not SW620, express vitamin D receptor whose activation by 1,25-dihydroxyvitamin D inhibits cell proliferation and clonogenic growth in soft agar [24 (link)]. HT 116 has a mutation in codon 13 of the ras protooncogene and expresses transforming growth factor beta 1 and beta 2. SW480 and SW620 cells are cultured in Leibovitz's L-15 medium with 10% FBS, and HT-29 and HCT 116 cells are cultured in McCoy's 5a medium with 10% FBS.

CRC cell lines LoVo, SW480, and SW620 were purchased from Bioresource Collection and Research Center (Hsinchu, Taiwan). The CPT-11-resistant clones developed from the LoVo cell line were cultured in RPMI 1640 (Gibco^® Grand Island, NY, USA) supplemented with 10% fetal calf serum (FCS; HyClone, Logan, Australia). All cells were incubated in a humidified chamber with 5% CO₂ at 37 °C. The cell medium was changed 48 h after subculture. Dulbecco’s phosphate-buffered saline (PBS; Gibco^®, Auckland, New Zealand) was used to wash the culture plate.

Human colorectal cancer cell lines, HCT116, SW480, and SW620, were obtained from Bioresource Collection and Research Center of Taiwan, and cultured in DMEM medium supplemented with 10% fetal bovine serum, 100 U/mL penicillin, 100 μg/mL streptomycin, and 2.5 μg/mL amphotericin B at 37°C in a 5% CO₂ incubator [38 (link)].