title: Targeting Metabolic Remodeling in Triple Negative Breast Cancer in a Murine Model.
abstract: Background:Chemotherapy is the backbone of systemic treatment for triple negative breast cancer (TNBC), which is one of the most relevant breast cancers molecular types due to the ability of tumor cells to develop drug resistance, highlighting the urgent need to design newer and safer drug combinations for treatment. In this context, to overcome tumor cell drug resistance, we employed a novel combinatorial treatment including Doxorubicin, Metformin, and Sodium Oxamate (DoxMetOx). Such pharmacological combination targets indispensable hallmarks of cancer-related to aerobic glycolysis and DNA synthesis.Materials and Methods:Thirty-five female nude mice were transplanted subcutaneously with MDA-MB-231 triple negative human cancer cell line. Once tumors were visible, mice were treated with doxorubicin, metformin, oxamate or all possible pharmacologic combinations. Treatments were administered daily for 15 days and tumors were measured by calipers every day. MicroPET images were taken in three different occasions, basal state, in the middle of the treatment, and at the end of treatment. Western blot analyses, qRT-PCR, flow cytometry, and cytotoxicity assays were performed to elucidate the mechanism of cell death promoted by the drugsin vitro.Results:In this work we assessed the proof of concept of metabolic correction in solid tumors as an effective drug treatment; hence, mice bearing tumors treated with the DoxMetOx therapy showed a complete inhibition of the tumor mass growing in 15 days of treatment depicted by the micro PET images.In vitrostudies displayed that the three drugs together act by inhibiting both, mTOR-phosphorylation and expression of LDH-A gene, promoting apoptosis via dependent on the caspase-3 pathway, accompanied by cleavage of PARP. Moreover, induction of autophagy process was observed by the accumulation of LC3-II, a primordial protein implicated in the conformation and elongation of the autophagolysosome.Conclusions:The lack of effective drugs to inhibit TNBC growth is the main cause of therapy failure and tumor relapse. We have showed that targeting crucial molecular pathways in cancer by the combination of Doxorubicin, Metformin, and Oxamate resulted as an efficient and rapid tumor growth inhibitor in a triple negative xenograft model. Our findings are promising for patients diagnosed with TNBC tumors, for which unfortunately there are no reliable drug therapies.
authors.affiliation: Posgrade in Experimental Biology, Metropolitan University of Mexico;; FES-Iztacala, UBIMED, National Autonomous University of Mexico, UNAM, Tlalnepantla, Mexico.
authors.forename: Verónica
authors.initials: V
authors.lastname: García-Castillo
authors.affiliation: Posgrade in Experimental Biology, Metropolitan University of Mexico.
authors.forename: Eduardo
authors.initials: E
authors.lastname: López-Urrutia
authors.affiliation: Biochemistry Unit, National Nutrition Institute of Mexico "Salvador Zubirán", Mexico.
authors.forename: Octavio
authors.initials: O
authors.lastname: Villanueva-Sánchez
authors.affiliation: PET/CT Unit, Faculty of Medicine, UNAM.
authors.forename: Miguel Á
authors.initials: MÁ
authors.lastname: Ávila-Rodríguez
authors.affiliation: Biochemistry Unit, National Nutrition Institute of Mexico "Salvador Zubirán", Mexico.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Zentella-Dehesa
authors.affiliation: Genomics Lab, National Cancer Institute of Mexico, Mexico.
authors.forename: Carlo
authors.initials: C
authors.lastname: Cortés-González
authors.affiliation: Posgrade in Genomic Sciences, Autonomous University of México City, Mexico.
authors.forename: César
authors.initials: C
authors.lastname: López-Camarillo
authors.affiliation: Biochemistry Unit, National Nutrition Institute of Mexico "Salvador Zubirán", Mexico.
authors.forename: Nadia J
authors.initials: NJ
authors.lastname: Jacobo-Herrera
authors.affiliation: FES-Iztacala, UBIMED, National Autonomous University of Mexico, UNAM, Tlalnepantla, Mexico;; Genomics Lab, National Cancer Institute of Mexico, Mexico.
authors.forename: Carlos
authors.initials: C
authors.lastname: Pérez-Plasencia
keywords: Triple Negative Breast Cancer (TNBC); aerobic glycolysis; doxorubicin; mTOR; metformin; micro PET.; oxamate; xenograft