Ferroportin Repression in Head and Neck Squamous Cell Carcinoma

项目摘要 铁是几乎所有生物体所需的基本元素。由于其气体结合和氧化还原 它在人体生理学中起着不可替代的作用，有助于促进必要的反应， 维持生命。转运铁蛋白（FPN）是人体内唯一的铁外排蛋白， 通过这个单一的渠道。因此，FPN在维持人体铁稳态中起关键作用。 调节激素hepcidin通过诱导FPN来控制膜相关FPN的水平。 通过直接结合的内吞作用和蛋白酶体降解。尽管它对宿主生理学很重要， 已知FPN和铁稳态在头颈癌进展中的作用。初步 工作表明FPN在口腔的正常细胞（口腔角质形成细胞和牙龈成纤维细胞）中表达。 我们发现FPN的抑制和铁稳态的失调发生在晚期（转移性）头部， 颈部鳞状细胞癌（HNSCC）。初步数据还显示，铁转运蛋白减少的细胞系 水平可能使细胞对铁凋亡更敏感。免疫印迹法检测hepcidin在HNSCC中的表达 细胞系，表明异常铁调素表达可能在这些细胞类型中的膜铁转运蛋白抑制中起作用。 该提案的目的是研究FPN抑制在HNSCC进展中的作用。我们将 还通过小角X射线散射（SAXS）探测FPN和hepcidin的相互作用， 铁调素介导的FPN抑制的分子机制。在目标1中，我们将研究临床病理学 FPN的抑制。我们将通过调节HNSCC细胞系中膜铁转运蛋白的水平，观察其对HNSCC细胞系中膜铁转运蛋白表达的影响。 对细胞增殖、转移潜能和对铁凋亡的敏感性有影响。在目标2中，我们将探索 hepcidin在FPN抑制中的作用，并研究hepcidin-FPN的变构机制 使用SAXS进行交互。这项研究的发现，尽管结果，将是重要的特点， 铁稳态在口腔健康和疾病中的作用。该奖学金培训计划将为申请人提供 在细胞和癌症生物学领域以及膜处理和纯化方面的经验 proteins.申请人的培训将由具有铁生物学和铁代谢领域专业知识的导师赞助。 癌症生物学，以及在与其他学员的环境。

Project Summary Iron is an essential element that is required in nearly all living organisms. Due to its gas binding and redox properties it plays an irreplaceable role in human physiology helping to facilitate the reactions necessary to sustain life. Ferroportin (FPN) acts as the sole iron efflux protein in humans, and all iron transport to the plasma occurs through this single channel. Thus, FPN plays a critical role in the maintenance of human iron homeostasis. The regulatory hormone hepcidin controls the levels of membrane associated FPN through the induction of endocytosis and proteasomal degradation via direct binding. Despite its importance to host physiology, very little is known about the role FPN, and iron homeostasis, plays in progression of head and neck cancers. Preliminary work shows that FPN is expressed in normal cells of the oral cavity (oral keratinocytes and gingival fibroblasts). We show repression of FPN and de-regulation of iron homeostasis occurs in advanced (metastatic) head and neck squamous cell carcinoma (HNSCC). Preliminary data also reveals that cell lines with reduced ferroportin levels may make cells more sensitive to ferroptosis. Immunoblots reveal the expression of hepcidin in HNSCC cell lines, indicating that aberrant hepcidin expression may play a role in ferroportin repression in these cell types. The goal of this proposal is to investigate the role FPN repression plays in the progression of HNSCC. We will also probe the interaction of FPN and hepcidin through Small Angle X-ray scattering (SAXS) to shed light on the molecular mechanisms of hepcidin mediated repression of FPN. In aim 1 we will investigate the clinicopathology of FPN repression in HNSCC. We will modulate ferroportin levels in HNSCC cell lines and observe the effect it has on cell proliferation, metastatic potential, and sensitivity to ferroptosis. In aim 2 we will we will explore the role hepcidin plays in the repression of FPN and investigate the allosteric mechanisms of the hepcidin-FPN interaction using SAXS. The findings in this study, despite the outcomes, will be important in characterizing the role iron homeostasis plays in oral health and disease. This fellowship training plan will provide the applicant experience in the fields of cell and cancer biology as well as in the handling and purification of membrane proteins. Training of the applicant will be sponsored by mentors with expertise in the fields of iron biology and cancer biology, as well as in an environment with other trainees.