Novel calcitriol analogues EM1 and UVB1 against aggressive breast cancer cells as a monotherapy or in combination with paclitaxel.

GUEVARA, J.A.; PAOLILLO, G.; IBARRA, A.; ALONSO, E.N.; ARENAS LAHUERTA, E.J.; NADAL SERRANO, M.; ARRIBAS, J.; BERNADÓ, C.; FALL, Y.; MASCARÓ, E.; VITALE, C.; CURINO, A.C.; FACCHINETTI, M.M.; FERRONATO, M.J.

Mar del Plata

Congreso; LXIV Reunión Científica Anual de la Sociedad Argentina de Investigación Clínica (SAIC); 2019

Sociedad Argentina de Investigaciones clínicas

Despite chemotherapy remaining as a primary therapeutic option for aggressive breast cancer (BC), its effectiveness is limited by intrinsic or acquired resistance and associated adverse effects. Therefore, new therapeutic strategies are needed. Previously, we demonstrated that the calcitriol analogue EM1 decreases the viability, migration and invasion of the 4T1 triple-negative BC (TNBC) cells. Additionally, we reported that UVB1, another calcitriol analogue synthetized by our group, reduces the viability of cells derived from the TNBC - Patient-Derived Xenografts (PDX). Hence, the aim of the present study was to continue evaluating the antitumoral effects of the calcitriol analogues EM1 and UVB1 on aggressive BC cells, alone or in combination with low concentrations of Paclitaxel (PTX). We found a synergistic effect by combining EM1 or UVB1 with non-effective PTX concentrations on viability of 4T1 cells. The resulting Combination Index values of Chou & Talalay method were 0.80059 and 0.13491 for EM1-PTX and UVB1-PTX combinations, respectively. In addition of our previous result on 4T1 cell migration, EM1 displayed antimigratory effects on MDA-MB-231 TNBC cell line (p