Foetal bovine serum (fbs)

OE19, and ESO26 cells were cultured in RPMI 1640 (ThermoFisher Scientific, 52400) supplemented with 10% foetal bovine serum (ThermoFisher Scientific, 10270) and 1% penicillin/streptomycin (ThermoFisher Scientific, 15140122). KYAE1 cells were cultured in 1:1 RPMI 1640:F12 (ThermoFisher, 11765054) supplemented with 10% foetal bovine serum and 1% penicillin/streptomycin. The OAC organoid WTSI-OESO_009 was cultured as described previously (9 (link)). HEK293T cells were cultured in DMEM (ThermoFisher Scientific, 22320-022) supplemented with 10% foetal bovine serum. Cell lines were cultured at 37°C, 5% CO₂ in a humidified incubator.

The HCC cell lines HepG2, HepG3B and SMMC7221 we used were obtained from the American Type Culture Collection (Rockville, MD, USA) in 2012 and authenticated using short tandem repeat (STR) analysis by Genewiz Inc. in 2014. STR analysis showed that the submitted samples were in good agreement with the reference cell lines. The HCC cell line Bel7402 was obtained from KeyGEN BioTECH and we finished our studies within 6 months. HepG2 cells were cultured in Modified Eagle's Medium supplemented with 10% foetal bovine serum, SMMC7721 cells were cultured in Dulbecco's Modified Eagle's Medium supplemented with 10% foetal bovine serum, while Bel7402 and HepG3B were cultured in Roswell Park Memorial Institute 1640 supplemented with 10% foetal bovine serum (Invitrogen). The vectors were transfected into cells using a percutaneous ethanol injection (cat no. 23966; Polysciences, Inc.).

Normal human melanocyte cell line NHEM was cultured in Ham's F10 media supplemented with ITS premix (Becton Dickinson, Franklin Lakes, NJ). Human melanoma cell lines WM793B, WM35, A2058, A375 and 451Lu were obtained from American Type Culture Collection (ATCC, Manassas, VA). WM35 and 451Lu cell lines were cultured in RPMI 1640 medium (Invitrogen) supplemented with 10% foetal bovine serum (Invitrogen). WM793B cell line was maintained in MCDB153 medium with 10% foetal bovine serum (Invitrogen). A2058 and A375 cell lines were cultured in Dulbecco's MEMV F12 medium (Invitrogen) supplemented with 10% foetal bovine serum (Invitrogen). Cisplatin (Sigma‐Aldrich, St Louis, MO) was used at a concentration of 25 μmol/L unless specified description.

The prostate and prostate cancer cell lines that were used in this experiment, including TrampC1, RM1, CAF and NF, were all derived from Dr. Chang, George Whipple Lab for Cancer Research, and these four types of cells are of mouse origin [16 (link), 17 (link)]. TrampC1 and RM1 were cultured in RPMI-1640 medium (Gibco, Waltham, MA USA) containing 10% foetal bovine serum (Gibco, Waltham, MA USA) and culture conditions of 37 °C with 5% CO₂. CAF and NF were cultured in DMEM (Gibco, Waltham, MA USA) containing 10% foetal bovine serum (Gibco, Waltham, MA USA) and incubated at 37 °C with 5% CO₂.
In this experiment, human prostate cancer hCAF and human prostate hNF were taken from the primary culture of urological surgical specimens from the Second Hospital of Tianjin Medical University. The hCAF and hNF samples were cultured in DMEM (Gibco, Waltham, MA USA) containing 10% foetal bovine serum (Gibco, Waltham, MA USA) and incubated at 37 °C with 5% CO2.

HUVEC were obtained from Lonza (Breda, The Netherlands) and the Endothelial Cell Facility of University Medical Center Groningen, The Netherlands. Cells were maintained in endothelial cell medium, composed of, RPMI 1640 basal medium (Lonza, Verviers, Belgium), supplemented with 20% heat-inactivated foetal bovine serum (Invitrogen/GIBCO, CA, USA), 50 μg/ml endothelial cell growth factors supplement (bovine brain extract; homemade), 1% penicillin-streptomycin (Sigma-Aldrich, MA, USA), 2 mM L-glutamine (Lonza) and 5 U/ml heparin (Leo Pharma, Ballerup, Denmark). Cells were used for experiments at passage 6 and 7.
Confluent monolayers of HUVEC were stimulated for 48 h with or without 5 or 10 ng/ml citric acid activated-TGF-β1 (Peprotech, NJ, USA; #100–21 C) in RPMI 1640 basal medium, supplemented with 20% heat-inactivated foetal bovine serum, 2 mM L-glutamine, 5 U/ml heparin and 1% penicillin-streptomycin. Cells treated with endothelial cell medium were harvested as unstimulated controls, Cells were treated with pharmacological inhibitors for 48 h to inhibit desired signalling pathways.

The hTERT-immortalized human retinal pigment epithelial cells (hTERT-RPE-1) were obtained from ATCC (Manassas, VA) and grown in DMEM/F12, 1:1 (Gibco, Thermo Fisher Scientific Inc., Waltham, MA, USA) medium supplemented with 10% foetal bovine serum (Gibco, Thermo Fisher Scientific Inc., Waltham, MA, USA), penicillin/streptomycin (Gibco, Thermo Fisher Scientific Inc., Waltham, MA, USA), and 0.01 mg/ml hygromycin-B (Millipore Sigma, Darmstadt, Germany). The cells were tagged with mEmerald-vimentin using the TALEN genome editing approach, which has been previously described^{29 (link)}. For imaging, the cells were placed into collagen as previously described^{21 (link)}. MV3 cells were obtained from Peter Friedl (MD Anderson Cancer Center, Houston TX). The MV3 cells were cultured in DMEM (Gibco, Thermo Fisher Scientific Inc., Waltham, MA, USA) supplemented with 10% foetal bovine serum (Thermo Fisher Scientific Inc., Waltham, MA, USA) at 37 °C and 5% CO₂. The cells were infected to express GEMs using a lentiviral construct from Addgene (Plasmid #116934^{22 (link)}). The cells were sorted by fluorescence activated cell sorting to purify the population of cells expressing GEMs.