The role of serine metabolism on the evolution of oral squamous cell carcinoma

丝氨酸代谢在口腔鳞状细胞癌演变中的作用

• 批准号: 10825875
• 负责人: Stacy Jankowski
• 金额: $ 4.85万
• 依托单位: BOSTON UNIVERSITY MEDICAL CAMPUS
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-12 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10825875
• 关键词: Alcohol consumption; Algorithms; Anabolism; Anatomy; Biochemical; Biological; Biological Assay; Carcinoma; Cell Communication; Cell Differentiation process; Cell Line; Cell Lineage; Cells; Chromatin; Chromatin Structure; Clinical; Cluster Analysis; Complex; Coupled; Development; Dietary Intervention; Differentiated Gene; Differentiation Antigens; Dioxygenases; Environment; Enzymes; Epigenetic Process; Epithelium; Evolution; Genes; Genomics; Global Change; Growth; Head and Neck Cancer; Heterogeneity; Histones; Human; Human Papillomavirus; Immunofluorescence Immunologic; Immunohistochemistry; In Vitro; Invaded; Isogenic transplantation; Knowledge; Lead; Lysine; Malignant Epithelial Cell; Malignant Neoplasms; Mesenchymal; Messenger RNA; Metabolism; Modeling; Modification; Morbidity - disease rate; Morphology; Neoplasm Metastasis; Nuclear; Nutrient; Operative Surgical Procedures; Outcome; Pathway interactions; Patients; Pharmaceutical Preparations; Phenotype; Play; Population; Proliferating; Proliferation Marker; Proteins; Radiation therapy; Repression; Research; Resistance; Role; Science; Serine; Signal Pathway; Starvation; Therapeutic; Tobacco use; Transcription Initiation Site; Validation; Western Blotting; Withdrawal; advanced disease; alpha ketoglutarate; cancer stem cell; cancer therapy; cell motility; chemotherapy; cost effective; demethylation; deprivation; derepression; dietary; dietary restriction; enzyme pathway; epigenomic profiling; epigenomics; histone modification; in vivo; insight; malignant mouth neoplasm; migration; mortality; mouse model; mouth squamous cell carcinoma; neoplastic cell; novel; novel therapeutic intervention; novel therapeutics; precision nutrition; programs; response; side effect; stem; stem cell genes; stem cell population; stemness; success; targeted treatment; therapeutically effective; trait; treatment response; tumor; tumor growth; tumor heterogeneity; tumor progression; tumorigenic; uptake

ABSTRACT Oral squamous cell carcinoma (OSCC) is a devastating malignancy associated with high morbidity, poor survival, and few therapeutic options. OSCC is characterized by heterogeneous cell states, including cancer stem cells (CSCs), which drive metastasis and therapy resistance. Although there has been some modest success with targeted therapies, there remains a need for more effective therapeutic options for OSCC. Increasing evidence has shown that changes in serine metabolism can direct cell fate via epigenomic changes. Endogenous serine synthesis generates a by-product, alpha-ketoglutarate (αKG), which is a co-substrate for nuclear αKG- dependent dioxygenases to demethylate histone marker H3K27me3 and de-repress differentiation genes. We have shown that under serine starvation conditions, metastatic OSCC HSC3 cells slowed proliferation concomitant with a change in morphology from mesenchymal to epithelial, compared to cells grown in complete medium. This was associated with a statistically significant increase in the steady-state mRNA and enzyme levels in the serine synthesis pathway under serine starvation conditions, indicating that HSC3 cells rely on exogenous serine for growth. The observed switch from exogenous serine uptake to endogenous serine synthesis in HSC3 cells was accompanied by an increase in αKG concentration. Furthermore, serine starvation and increased αKG were associated with decrease of repressive histone marker H3K27me3, thus de-repressing terminal epithelial differentiation genes. Simultaneously, there is a decrease in H3K4me3, a marker of open chromatin structure, associated with the promotion of stemness genes and aggressive cancer traits in OSCC. Initial studies into the plasticity of the stem-like identity using the tumorsphere formation assay shows that serine starvation leads to a lack of tumorspheres stability. Our findings suggest that a switch from exogenous serine uptake to the endogenous serine biosynthesis promotes OSCC cell differentiation concomitant with the loss of CSC identity. Given my preliminary studies, I hypothesize that serine deprivation promotes epigenetic changes that inhibit CSCs and OSCC progression to advanced disease. I will investigate our hypotheses through two aims. My first aim will be to determine mechanisms underlying epigenetic modifications in a panel of OSCC cell lines in response to serine deprivation in vitro. This will be investigated through use of migration and invasion assays, in depth tumorsphere analysis, and epigenomic profiling. My second aim will be to define changes in tumor size and tumor cell populations in response to dietary serine restriction in vivo, utilizing a syngeneic 4MOSC1 isograft mouse model of OSCC to interrogate the heterogeneity of tumor cell populations through scRNAseq with biochemical validation. These studies will fill the gap in knowledge how changes in serine metabolism impact the epigenomic environment and provide insight into novel therapeutic options for OSCC.

摘要 口腔鳞状细胞癌（OSCC）是一种严重的恶性肿瘤，发病率高，生存率低， 治疗选择也很少口腔鳞状细胞癌的特点是异质性细胞状态，包括癌症干细胞 （CSC），其驱动转移和治疗抗性。虽然已经取得了一定的成功， 尽管存在靶向治疗，但仍然需要更有效的OSCC治疗选择。越来越多的证据 已经表明丝氨酸代谢的变化可以通过表观基因组变化来指导细胞命运。内源丝氨酸 合成产生副产物α-酮戊二酸（αKG），它是核αKG-的共底物。 依赖性双加氧酶去甲基化组蛋白标记H3 K27 me 3和去抑制分化基因。我们 已经表明，在丝氨酸饥饿条件下，转移性OSCC HSC 3细胞的增殖减慢 与完全生长的细胞相比，伴随着从间充质到上皮的形态变化， 介质这与稳态mRNA和酶的统计学显著增加有关。 水平的丝氨酸合成途径在丝氨酸饥饿条件下，表明HSC 3细胞依赖于 外源丝氨酸对生长的影响。观察到的从外源性丝氨酸摄取到内源性丝氨酸摄取的转变 HSC 3细胞中的α KG合成伴随着αKG浓度的增加。此外，丝氨酸饥饿 而αKG的增加与抑制性组蛋白标记物H3 K27 me 3的减少有关，从而解除了抑制作用。 终末上皮分化基因同时，H3 K4 me 3减少，H3 K4 me 3是开放的标志物。 染色质结构，与干性基因的促进和口腔鳞癌的侵袭性癌症特征有关。 使用肿瘤球形成测定对茎样身份的可塑性的初步研究表明丝氨酸 饥饿导致肿瘤球缺乏稳定性。我们的研究结果表明，从外源丝氨酸的开关， 对内源性丝氨酸生物合成的摄取促进了OSCC细胞的分化，同时伴随着内源性丝氨酸生物合成的丧失。 CSC身份。根据我的初步研究，我假设丝氨酸缺失促进了表观遗传变化 抑制CSC和OSCC进展为晚期疾病。我将通过两个方面来研究我们的假设 目标。我的第一个目标是确定一组OSCC细胞中表观遗传修饰的潜在机制， 线在体外丝氨酸剥夺的反应。这将通过使用迁移和入侵进行调查 分析，深入肿瘤球分析和表观基因组分析。我的第二个目标是定义 肿瘤大小和肿瘤细胞群对饮食丝氨酸限制的体内反应， OSCC的4 MOSC 1同种移植小鼠模型，以通过以下方式询问肿瘤细胞群体的异质性： 具有生物化学验证的scRNAseq。这些研究将填补知识上的差距， 代谢影响表观基因组环境，并为OSCC提供新的治疗选择。