ERBB2 and breast cancer: Phase contrast microscopy images (Supplemental Figures S1–S3) revealed distinct morphological changes in breast cancer cells following CHCP treatment at 25 V and 30 V. In untreated Hs578T (ER−/PR−/HER2−) cells, membranes exhibited well-defined borders (black arrows), whereas treated cells displayed membrane blebbing and cell shrinkage within 1 h, indicative of oxidative stress (red arrows).