Truncated O-glycan-dependent mechanisms inducing metastatic dissemination in pancreatic cancer

截短的O-聚糖依赖性机制诱导胰腺癌转移扩散

• 批准号: 10503433
• 负责人: Surinder K. Batra
• 金额: $ 52.69万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-12 至 2027-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10503433
• 关键词: Acetylgalactosamine; Affect; Antigens; Appearance; Applications Grants; CD44 gene; CRISPR/Cas technology; Cancer Etiology; Carbohydrates; Cessation of life; Clinical; Co-Immunoprecipitations; Data; Disease; Disease Progression; Distant; Distant Metastasis; Galactose; Galactosyltransferases; Glycobiology; Glycopeptides; Glycoproteins; Goals; Histocytochemistry; Human; Incidence; KPC model; KRASG12D; Knock-out; Lectin; Liver; Lung; Malignant Neoplasms; Malignant neoplasm of pancreas; Mass Spectrum Analysis; Mediating; Membrane; Modeling; Molecular; Molecular Weight; Mucin 1 protein; Mucins; Mus; Mutation; Neoplasm Metastasis; Normal Cell; Normal tissue morphology; O-Glycans Biosynthesis Pathway; Oncogenic; Organ; Organoids; Pathway interactions; Peptides; Peritoneum; Play; Polysaccharides; Quantitative Evaluations; Role; Sampling; Severity of illness; Structure; TP53 gene; Testing; Therapeutic; Tissues; Translating; Tumorigenicity; Vaccines; Variant; Vertebral column; base; cancer stem cell; carbohydrate structure; clinical diagnosis; clinically significant; design; early onset; glycosylation; glycosyltransferase; improved; in vivo; insight; lymph nodes; mortality; mouse model; novel therapeutic intervention; novel therapeutics; pancreatic cancer cells; pancreatic cancer patients; prevent; stem cell biomarkers; stemness; success; sugar; transcriptome sequencing; tumor progression; tumorigenesis

Pancreatic cancer (PC) is the fourth leading cause of cancer death and often goes undiagnosed until it has already advanced and metastasized. Aberrant changes in O-glycans, such as increased expression of truncated carbohydrate antigens (Tn, sialylated Tn/STn), are commonly observed in PC. However, the mechanistic involvement of these truncated O-glycan structures in PC progression and metastasis is under-explored. Hence, our study is focused on investigating the mechanistic role of truncated O-glycans during early metastatic dissemination in PC. The O-glycosyltransferase Core 1 β1,3-Galactosyltransferase (C1GALT1) catalyzes the second step of mucin-type O-glycan biosynthesis by adding galactose to the first sugar N-acetylgalactosamine (Tn) that forms the Core 1 carbohydrate structure. Such structures are usually elongated to mature O-glycans found on normal tissue, but their extension may be truncated at the Tn-glycan stage during cancer due to inactive C1GALT1 activity. Our preliminary data demonstrated the loss of O-glycosyltransferase activity, C1GALT1, in a subset of (poorly differentiated) human PC tissue. Further, CRISPR/Cas9-based C1GALT1 knockout (KO) in PC cells resulted in aberrant O-glycosylation (increased Tn and STn glycans). Along with glycan alterations presented upon oncogenic glycoproteins (mucin glycoproteins and cancer stem cell markers), our studies also indicate increased tumorigenicity and metastasis of C1GALT1 KO PC cells. We have also observed O-glycan truncation present on CD44, a cancer stem cell marker, in C1GALT1 models. Interestingly, knockout of C1galt1 along with KrasG12D and Trp53R172H/+ mutations in mouse models resulted in early-onset (in 3 weeks) and early distant metastasis (in 10 weeks) of PC. Based on these observations, our major goal is to investigate the mechanistic role of truncated O-glycans in PC progression and metastasis. Based on these observations, we hypothesize that "Truncated O-glycans on cancer-associated glycoproteins (mucins and stemness markers) induce the early onset of progression and metastatic dissemination in pancreatic cancer." To test this hypothesis, the following aims are proposed. The first aim will investigate the functional impact of C1GALT1 expression and aberrant glycosylation profile on cancer-associated glycoproteins in pancreatic cancer. The second aim will elucidate how truncated O-glycans (such as Tn and STn) on membrane-bound mucins and stemness markers facilitate pancreatic cancer metastasis. The third aim will determine, in vivo, the impact of truncated O-glycans in the early onset of pancreatic cancer metastasis using C1galt1 knockout KC and KPC mice. The proposed studies will establish the association of aberrant expression of truncated Tn and STn glycans with differential membrane- bound mucin function during PC progression and metastasis. This study will significantly contribute to our knowledge of mucin glycobiology in cancer. Altogether, this proposed study will also pave the way for developing novel therapeutics for modulating membrane-bound mucin function in PC.

胰腺癌 (PC) 是癌症死亡的第四大原因，并且常常在确诊之前未被诊断出来。 O-聚糖的晚期和转移性变化，例如截短的表达增加。 碳水化合物抗原（Tn、唾液酸化 Tn/STn）在 PC 中很常见，但其机制却很常见。 这些截短的 O-聚糖结构在 PC 进展和转移中的作用尚未得到充分研究。 我们的研究重点是研究截短的 O-聚糖在早期转移过程中的机制作用 O-糖基转移酶核心 1 β1,3-半乳糖基转移酶 (C1GALT1) 催化 通过将半乳糖添加到第一糖N-乙酰半乳糖胺中进行粘蛋白型O-聚糖生物合成的第二步 (Tn) 形成核心 1 碳水化合物结构，此类结构通常会延长为成熟的 O-聚糖。 在正常组织中发现，但在癌症期间，由于不活跃，它们的延伸可能在 Tn 聚糖阶段被截断 我们的初步数据表明，C1GALT1 中 O-糖基转移酶活性丧失。 （低分化）人类 PC 组织的子集 此外，PC 中基于 CRISPR/Cas9 的 C1GALT1 敲除 (KO)。 细胞导致异常的 O-糖基化（Tn 和 STn 聚糖增加）以及聚糖改变。 关于致癌糖蛋白（粘蛋白糖蛋白和癌症干细胞标记物），我们的研究还表明 我们还观察到 C1GALT1 KO PC 细胞的致瘤性和转移性增加。 存在于 C1GALT1 模型中的癌症干细胞标记物 CD44 上。 小鼠模型中的 KrasG12D 和 Trp53R172H/+ 突变导致早发（3 周内）和早期远期症状 基于这些观察结果，我们的主要目标是研究 PC 的转移（10 周内）。 基于这些观察，我们探索了截短的 O-聚糖在 PC 进展和转移中的作用。 “癌症相关糖蛋白（粘蛋白和干细胞标记物）上的截短 O 聚糖会诱导早期 胰腺癌进展和转移扩散的发生。”为了检验这一假设，以下内容 提出的第一个目标是研究 C1GALT1 表达和异常的功能影响。 第二个目标是阐明胰腺癌中癌症相关糖蛋白的糖基化谱。 膜结合粘蛋白上的截短 O-聚糖（例如 Tn 和 STn）和干性标记促进 第三个目标将确定截短的 O-聚糖在早期体内的影响。 拟议的研究将使用 C1galt1 敲除 KC 和 KPC 小鼠来观察胰腺癌转移的发生。 建立截短的 Tn 和 STn 聚糖的异常表达与差异膜的关联 PC 进展和转移过程中结合粘蛋白的功能这项研究将对我们做出重大贡献。 总而言之，这项拟议的研究也将为癌症的发展铺平道路。 调节 PC 膜结合粘蛋白功能的新疗法。