RT info:eu-repo/semantics/article T1 Suppressive impact of metronomic chemotherapy using UFT and/or cyclophosphamide on mediators of breast cancer dissemination and invasion A1 Muñoz Martínez, Raquel A1 Hileeto, Denise A1 Cruz Muñoz, William A1 Wood, Geoffrey A. A1 Xu, Ping A1 Man, Shan A1 Viloria Petit, Alicia A1 Kerbel, Robert S. K1 Breast cancer K1 Cáncer de mama K1 Chemotherapy K1 Quimioterapia K1 Uracil-tegafur K1 Tegafur-uracilo K1 Cyclophosphamide K1 Ciclofosfamida AB Metronomic chemotherapy using the 5-FU prodrug uracil-tegafur (UFT) and cyclophosphamide (CTX) was previously shown to only modestly delay primary tumor growth, but nevertheless markedly suppressed the development of micro-metastasis in an orthotopic breast cancer xenograft model, using the metastatic variant of the MDA-MB-231 cell line, 231/LM2-4. Furthermore, a remarkable prolongation of survival, with no toxicity, was observed in a model of postsurgical advanced metastatic disease. A question that has remained unanswered is the seemingly selective anti-metastatic mechanisms of action responsible for this treatment. We assessed the in vivo effect of metronomic UFT, CTX or their combination, on vascular density, collagen deposition and c-Met (cell mediators or modulators of tumor cell invasion or dissemination) via histochemistry/immunohistochemistry of primary tumor sections. We also assessed the effect of continuous exposure to low and non-toxic doses of active drug metabolites 5-fluorouracil (5-FU), 4-hydroperoxycyclophosphamide (4-HC) or their combination, on 231/LM2-4 cell invasiveness in vitro. In the in vivo studies, a significant reduction in vascular density and p-Met[Y1003] levels was associated with UFT+CTX treatment. All treatments reduced intratumoral collagen deposition. In the in vitro studies, a significant reduction of collagen IV invasion by all treatments was observed. The 3D structures formed by 231/LM2-4 on Matrigel showed a predominantly Mass phenotype under treated conditions and Stellate phenotype in untreated cultures. Taken together, the results suggest the low-dose metronomic chemotherapy regimens tested can suppress several mediators of tumor invasiveness highlighting a new perspective for the anti-metastatic efficacy of metronomic chemotherapy. PB PLOS SN 1932-6203 YR 2019 FD 2019 LK http://uvadoc.uva.es/handle/10324/40999 UL http://uvadoc.uva.es/handle/10324/40999 LA eng NO PLoS ONE, 2019, vol. 14, n. 9. 28 p. NO Producción Científica DS UVaDOC RD 25-abr-2024