In contrast, ectopic expression of Kv10.1 is frequently detected in tumor biopsies (Figure 1, Table 1) and cancer cell lines; several reports estimate that Kv10.1 is overexpressed in around 70% of clinical tumor samples [24,41,42,43,44,45,46,47,48], where the Kv10.1 expression seems to confer some malignant or oncogenic properties, e.g., sustained proliferation. This evidence concerns the gene KCNH1 and neoplasm.