Edta solution

hiPSC-CMs were obtained from commercial products (JK Med, China) and could be observed to be spontaneously beating under a microscope (Supplementary Information File: Section S3). After washing in 1× dulbecco’s phosphate buffered saline (DPBS, Gibco, USA) twice for 5 min, hiPSC-CMs were digested with EDTA Solution (Stemcell Technologies, Canada) for 10 min, followed by the addition of cardiomyocyte support medium (Stemcell) to terminate digestion, centrifugation to remove the supernatant, and dilution of the hiPSC-CM suspensions with cardiomyocyte support medium.
The primary HUVECs were obtained from commercial products (JK Med), and passages 4–7 were used for the experiments (Supplementary Information File: Section S3). HUVECs were cultured in Endothelial Cell growth Medium-2 (EGM-2, CC-3162, Lonza, Switzerland) supplemented with 1% penicillin–streptomycin solution (Hyclone, China). HUVECs were grown to 90% confluence before use in cell culture flasks. After washing in 1× DPBS twice for 5 min, the HUVECs were removed from the cell culture flask using 0.25% trypsin solution (Saimike, China). Then, dulbecco’s modified eagle medium: F-12 (DMEM/F12, Hyclone) with 10% fetal bovine serum (FBS, Hyclone) was added to terminate digestion, the samples were centrifuged to remove the supernatant, and HUVEC suspensions were diluted with EGM-2.

Human neuroblastoma SH-SY5Y cells obtained from the American Type Culture Collection (ATCC^® No. CRL-2266TM) were routinely cultured following the ATCC’s instructions. A mixture of ATCC-formulated Eagle’s minimum essential medium (EMEM) (ATCC, USA) and F12 medium (Gibco, Gaithersburg, MD) was prepared at a 1:1 ratio (hereafter called EMEM-F12). To prepare a complete medium for human SH-SY5Y cells, EMEM-F12 medium was supplemented with 10% heat-inactivated fetal bovine serum (FBS, HyClone, USA), herein called complete EMEM-F12. Cells were incubated at 37 °C in a humidified atmosphere containing 5% CO₂. At a cell density of 60–80% confluence, cells were subcultured using 0.25% trypsin in 0.5 mM EDTA solution (STEMCELL Technologies, Vancouver, Canada). The number of viable cells was counted using Trypan blue and a hemocytometer.

Human neuroblastoma SH-SY5Y cells were obtained from the American Type Culture Collection (ATCC^® No. CRL-2266TM), while human lung carcinoma A549 cells were kindly provided by Prof. Wanpen Chaicumpa. Both cell types were maintained following the ATCC’s instructions. For the SH-SY5Y cells, a 1:1 ratio of ATCC-formulated Eagle’s minimum essential medium (EMEM) (ATCC, Utah) and F12 medium (Gibco, Gaithersburg, MD) was prepared. The complete medium of the human neuroblastoma SH-SY5Y cells is EMEM-F12 medium supplemented with 10% heat-inactivated FBS (HyClone, Utah), herein called complete EMEM-F12 medium. For the A549 cells, 10% FBS-supplemented DMEM was used. Cells were incubated at 37°C in a humidified atmosphere containing 5% CO₂ and subcultured every 2–3 days or when the cell density reached 60–80% confluence. Cells were detached from the polystyrene well using 0.25% trypsin in 0.5 mM EDTA solution (STEMCELL Technologies, Vancouver, Canada). Viable and nonviable cells were identified using Trypan blue and counted using a hemocytometer under a light microscope. Human neuroblastoma SH-SY5Y cells were subcultured at a 1:10 ratio per well of a 6-well plate.