KCNH2 and cancer: On the contrary, scFv-hERG1-Cys added for 24 hours to HEK 293 hERG1 cells, which over-express hERG1, or to different cancer cell lines (triple negative breast cancer cell line, MDA-MB231, pancreatic ductal adenocarcinoma cell lines, PANC-1 and MIAPaCa-2, colorectal cancer cell line, HCT-116) endowed with high endogenous hERG1 expression, significantly decreased cell viability (Figure 4C).