García-Castillo Verónica, López-Urrutia Eduardo, Villanueva-Sánchez Octavio, Ávila-Rodríguez Miguel Á, Zentella-Dehesa Alejandro, Cortés-González Carlo, López-Camarillo César, Jacobo-Herrera Nadia J, Pérez-Plasencia Carlos
Posgrade in Experimental Biology, Metropolitan University of Mexico;; FES-Iztacala, UBIMED, National Autonomous University of Mexico, UNAM, Tlalnepantla, Mexico.
Posgrade in Experimental Biology, Metropolitan University of Mexico.
J Cancer. 2017 Jan 13;8(2):178-189. doi: 10.7150/jca.16387. eCollection 2017.
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. 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 drugs . 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. studies 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. 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.
化疗是三阴性乳腺癌（TNBC）全身治疗的核心，TNBC是最相关的乳腺癌分子类型之一，因其肿瘤细胞具有产生耐药性的能力，这凸显了设计更新、更安全的联合用药方案用于治疗的迫切需求。在此背景下，为克服肿瘤细胞耐药性，我们采用了一种新型联合治疗方法，包括阿霉素、二甲双胍和草氨酸钠（DoxMetOx）。这种药物组合靶向与有氧糖酵解和DNA合成相关的癌症必需特征。35只雌性裸鼠皮下移植了MDA-MB-231三阴性人癌细胞系。一旦肿瘤可见，小鼠就接受阿霉素、二甲双胍、草氨酸或所有可能的药物组合治疗。每天给药15天，每天用卡尺测量肿瘤大小。在三个不同时间点进行MicroPET成像，即基础状态、治疗中期和治疗结束时。进行蛋白质免疫印迹分析、qRT-PCR、流式细胞术和细胞毒性试验以阐明药物促进细胞死亡的机制。在这项工作中，我们评估了实体瘤代谢校正作为一种有效药物治疗的概念验证；因此，接受DoxMetOx治疗的荷瘤小鼠在治疗15天后肿瘤体积完全受到抑制这一点通过MicroPET图像得以体现。研究表明，这三种药物共同作用，通过抑制mTOR磷酸化和LDH-A基因表达，经由依赖半胱天冬酶-3的途径促进细胞凋亡，并伴有PARP的裂解。此外，通过自噬相关蛋白LC3-II的积累观察到自噬过程的诱导，LC3-II是一种参与自噬溶酶体形成和延长的原始蛋白。缺乏有效的药物来抑制TNBC生长是治疗失败和肿瘤复发的主要原因。我们已经表明，通过联合使用阿霉素、二甲双胍和草氨酸靶向癌症中的关键分子途径，在三阴性异种移植模型中可产生高效且快速的肿瘤生长抑制作用。我们的研究结果对于被诊断患有TNBC肿瘤的患者很有前景，遗憾的是目前尚无可靠的药物治疗方法。
