The combined therapy slows the growth of tumors more efficiently than each drug individually. MBCDF and T-47D cells were xenografted subcutaneously in nude mice. Treatment started after a palpable mass was evident (initial volume) and was administered during 3 weeks. A) Fold increase from initial volume was calculated for each tumor by dividing the volume on day 21/initial volume. Vehicle (Vh); calcitriol (C), astemizole (A), combined therapy (CA). Black bars = MBCDF; white bars = T-47D. Mean ± standard error. *P < 0.05 vs vehicle in each group, **P < 0.05 vs calcitriol alone. n ≥ 15 mice in each group. B, C, D and E) Representative pictures depicting tumor final size after treatment with vehicle, calcitriol, astemizole and the combination of both drugs, respectively.