As shown in Figure S1a–d (Supporting Information), the MDA‐MB‐231 triple negative human breast cancer cells and PC‐3 human prostate cancer cells can form some loose aggregates, while the MCF‐7 human epidermal growth factor (EGF) receptor 2 (HER2)+ human breast cancer cells and OVCAR‐8 human ovarian cancer cells can form tight cell spheroids under the ULAP culture. The gene discussed is ERBB2; the disease is breast cancer.