Amino acid transporter SLC38A5 as a drug target for TNBC: Evaluation with genetic and pharmacologic approaches

氨基酸转运蛋白 SLC38A5 作为 TNBC 的药物靶点：用遗传和药理学方法进行评估

• 批准号: 10576760
• 负责人: VADIVEL GANAPATHY
• 金额: $ 21.46万
• 依托单位: TEXAS TECH UNIVERSITY HEALTH SCIS CENTER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-12-16 至 2024-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10576760
• 关键词: Amino Acid Transporter; Amino Acids; Anthelmintics; Attention; Automobile Driving; Biochemical Pathway; Breast Cancer Cell; Breast Cancer cell line; Cancer Cell Growth; Carbon; Cell Line; Cell Proliferation; Cells; Clinical Trials; Coupled; DNA Methylation; Data; Drug Targeting; Epigenetic Process; Essential Amino Acids; Estrogen receptor positive; Evaluation; FDA approved; Future; Genetic; Genetic Transcription; Glutamine; Glycine; Goals; Growth; Growth and Development function; Human; In Vitro; Knockout Mice; Logic; Lysine; Malignant Neoplasms; Mammary Neoplasms; Mediating; Metabolic Pathway; Metabolism; Methionine; Methylation; Molecular; Mus; Normal Cell; Nude Mice; Pathway interactions; Pharmaceutical Preparations; Pre-Clinical Model; Proliferating; Protein Biosynthesis; Purines; Pyrimidine; Role; Serine; Specificity; System; Testing; Therapeutic; Up-Regulation; WNT Signaling Pathway; Xenograft procedure; addiction; amino acid metabolism; anti-cancer; cancer cell; cancer therapy; carcinogenesis; chemotherapy; drug repurposing; druggable target; in vivo; inhibitor; malignant breast neoplasm; meter; mouse model; neoplastic cell; novel; nucleotide metabolism; patient derived xenograft model; pharmacologic; pre-clinical; small hairpin RNA; targeted treatment; tool; triple-negative invasive breast carcinoma; tumor; tumor growth; uptake

Amino acid metabolism in tumor cells is very different from that in normal cells. The tumor-specific metabolic pathway “glutaminolysis” focuses on glutamine. Recently, another fundamental pathway was discovered for cancer cell proliferation: the “serine-glycine-methionine-one-carbon” pathway. Tumor cells upregulate specific amino acid transporters to satisfy their increased need for glutamine, glycine, serine, and methionine to fuel these pathways. Blocking the entry of these amino acids into tumor cells has potential for cancer therapy. Recently, we provided evidence for this approach by identifying SLC6A14, an amino acid transporter with broad specificity, that is induced in ER-positive (ER+) breast cancer (BC) and by showing that blockade of this transporter reduces ER+ BC. But, SLC6A14 is not expressed in triple-negative breast cancer (TNBC). TNBC must rely upon a different transporter as a “fix” to its “addiction” to glutamine/serine/glycine/methionine. We have now identified this transporter as SLC38A5, a Na+-coupled uptake system exclusively for these four amino acids. SLC38A5 is upregulated in TNBC by WNT/DVL1. Furthermore, SLC38A5 promotes macropinocytosis, a unique feature essential for tumor growth. Here we will show that SLC38A5 drives the glutamine- and one-carbon metabolic pathways in TNBC and evaluate in preclinical models the potential of this transporter as a logical drug target for TNBC. We have identified the FDA-approved drug niclosamide as a potent inhibitor of SLC38A5 function and expression. This drug can be used pharmacologically to interrogate the role of SLC38A5 in TNBC. We also have Slc38a5-null mice as a genetic tool for these studies. Hypothesis: SLC38A5 drives the glutamine-dependent and one-carbon metabolic pathways in TNBC; as such, pharmacologic inhibition or genetic deletion of SLC38A5 will block TNBC. We will test this hypothesis with two aims: (Aim 1) Demonstrate that SLC38A5 is obligatory for glutaminolysis and one-carbon metabolic pathway to promote cell proliferation and remodeling of the epigenetic landscape in TNBC cells and elucidate the molecular mechanisms by which WNT/DVL1 induces SLC38A5 in these cells. Here we will use classical as well as patient-derived xenograft TNBC cell lines. (Aim 2) Evaluate the impact of SLC38A5 loss on tumor growth in mouse models of TNBC using Slc38a5-/- mice and niclosamide as a proof-of-concept for future use of this transporter as a selective drug target for TNBC. Here we will use xenografts of human TNBC cell lines in nude mice to evaluate the anticancer efficacy of niclosamide, and also compare the development/growth of spontaneous mammary tumors in a TNBC mouse model [C3(1)-TAg mouse] with and without niclosamide treatment (pharmacologic) and on Slc38a5+/+ and Slc38a5-/- backgrounds (genetic). Impact: With no known targeted therapy, chemotherapy is the only option for TNBC. Establishment of SLC38A5 as a drug target would aid future use of pharmacologics (e.g., niclosamide) to block its expression and transport function as a targeted therapy for TNBC, either as a monotherapy or in combination with standard chemotherapeutics.

肿瘤细胞中的氨基酸代谢与正常细胞中的氨基酸代谢非常不同。肿瘤特异性代谢 途径“谷氨酰胺溶解”集中于谷氨酰胺。最近，发现了另一条基本途径 癌细胞增殖：“丝甘氨酸 - 甲硫代氨酸 - 碳”途径。肿瘤细胞上调 特定的氨基酸转运蛋白满足了对谷氨酰胺，甘氨酸，丝氨酸和甲糖素的增加需求 为这些途径加油。阻止这些氨基酸进入肿瘤细胞的潜力可能是癌症 治疗。最近，我们通过鉴定SLC6A14（氨基酸转运蛋白）提供了这种方法的证据 具有广泛的特异性，这是在ER阳性（ER+）乳腺癌（BC）中诱导的，并通过证明了阻塞 该转运蛋白减少ER+ BC。但是，SLC6A14在三阴性乳腺癌（TNBC）中不表达。 TNBC必须依靠另一个转运蛋白作为对谷氨酰胺/丝氨酸/甘氨酸/甲二氨酸的“成瘾”的“固定”。 现在，我们已经将此运输蛋白确定为SLC38A5，这是一个专门针对这四个的Na+耦合摄取系统 氨基酸。 SLC38A5在TNBC中由WNT/DVL1更新。此外，SLC38A5促进 大型细胞增多症，这是肿瘤生长必不可少的独特特征。在这里，我们将证明SLC38A5驱动 TNBC中的谷氨酰胺和一碳代谢途径，并在临床前模型中评估 该转运蛋白是TNBC的逻辑药物靶标。我们已经确定了FDA批准的药物烟酰胺是 SLC38A5功能和表达的潜在抑制剂。该药物可以用药物询问 SLC38A5在TNBC中的作用。我们还将SLC38A5-NULL小鼠作为这些研究的遗传工具。 假设：SLC38A5在TNBC中驱动谷氨酰胺依赖性和一碳代谢途径；作为 这样的药物结肠抑制或SLC38A5的遗传缺失将阻止TNBC。我们将检验这个假设 有两个目的：（目标1）证明SLC38A5对于谷氨酰胺溶解和一碳代谢是必不可少的 促进TNBC细胞中表观遗传景观的细胞增殖和重塑的途径并阐明 Wnt/DVL1影响这些细胞中SLC38A5的分子机制。在这里，我们将使用古典 以及患者衍生的TNBC细胞系。 （AIM 2）评估SLC38A5损失对肿瘤的影响 使用SLC38A5 - / - 小鼠和烟酰胺作为未来使用的概念验证的TNBC鼠标模型的生长 该转运蛋白是TNBC的选择性药物靶标。在这里，我们将使用人类TNBC细胞系的Xenographyming 在裸小鼠中评估烟酰胺的抗癌效率，也比较发育/生长 带有和没有烟酰胺的TNBC小鼠模型[C3（1）-TAG小鼠]中的赞助乳腺肿瘤 治疗（药理学）以及SLC38A5+/+和SLC38A5 - / - 背景（遗传）。影响：没有已知的 有针对性的治疗，化学疗法是TNBC的唯一选择。建立SLC38A5作为药物靶标 将有助于未来使用药物学（例如烟酰胺）来阻止其表达和运输功能 作为单一疗法或与标准化学治疗剂结合使用的TNBC的靶向疗法。