KCNN4 and breast cancer: Accordingly, concerns were raised regarding the use of TRAM-34 because this ‘specific’ KCa3.1 blocker was shown to stimulate the proliferation of breast cancer cells via the activation of ERs [79] and, in addition, Agarwal and colleagues suggested that TRAM-34 in low micromolar concentrations may also inhibit multiple cytochrome P450 isoforms [80].