Colo201

The human cancer cell lines SW480, COLO201, COLO205 and the nontumorigenic immortal fibroblast human cell line KMST-6 were obtained from the Japanese Collection of Research Bioresources Cell Bank (Tokyo, http://cellbank.nibio.go.jp). The human fibroblast cell line CCD-112CoN, which was derived from normal colon tissue, was acquired from the American Type Culture Collection (Manassas, VA, USA), and the other cell lines described below were from the Cell Resource Centre for Biomedical Research, Institute of Development, Aging and Cancer (Tohoku University, Sendai, Japan). All cancer cell lines were maintained at subconfluency in RPMI 1640, KMST-6 cells were cultured in MEM, and CCD-112CoN cells were cultured in EMEM. All culture media were supplemented with 10% foetal bovine serum, and the cells were maintained at 37°C in a humidified atmosphere containing 5% humidified CO₂. The clear layers at the top of the medium were obtained and spotted onto assay plates to determine whether they induced a chemotactic response by C. elegans.

Human colon cancer DLD-1 (Cat# JCRB9094), WiDr (Cat# JCRB0224), and COLO201 (Cat# JCRB0226) cells were obtained from the Japanese Collection of Research Bioresources (JCRB) Cell Bank (Osaka, Japan), while SW480 (SW-480) (ATCC^® CCL-228^TM) cells were obtained from American Type Culture Collection (Manassas, VA). HUVECs were obtained from KURABO (Osaka, Japan). The colon cancer cells were maintained in RPMI-1640 (Sigma-Aldrich, St Louis, MO) containing 10% (v/v) heat-inactivated fetal bovine serum (FBS; Thermo Fisher Scientific, Waltham, MA), while the HUVECs were maintained in complete medium (Humedia-EG2; KURABO). All cell lines were cultured under an atmosphere of 95% air and 5% CO₂ at 37 °C. The Trypan blue exclusion test was used to determine the number of viable cells in a cell suspension, from which the cell proliferation ratio was calculated.