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）是癌症死亡的第四个主要原因，并且经常被诊断为 高级和转移。 O-Glycans的异常变化，例如截短的表达增加 在PC中通常观察到碳水化合物抗原（TN，溶解的TN/STN）。但是，机械 这些被截断的O-聚糖结构参与PC进展和转移的参与不足。因此， 我们的研究重点是研究早期转移过程中截短的O-聚糖的机理作用 在PC中传播。 O-糖基转移酶核心1β1,3-乳糖基转移酶（C1GALT1）催化 粘蛋白型O-聚糖生物合成的第二步，通过向第一个糖N-乙酰乳糖胺添加半乳糖 （TN）构成核心1碳氢化物结构。这样的结构通常会拉长到成熟的O-Glycans 在正常组织上发现，但由于无活性，它们的延伸可能在癌症的TN-聚糖阶段被截断 C1GALT1活性。我们的初步数据证明了O-糖基转移酶活性C1GALT1的丧失 （分化差的）人PC组织的子集。此外，PC中的基于CRISPR/CAS9的C1GALT1淘汰赛（KO） 细胞导致异常的O-糖基化（TN和STN聚糖增加）。以及提出的聚糖改变 在致癌糖蛋白（粘蛋白糖蛋白和癌症干细胞标记物）上，我们的研究也表明 C1GALT1 KO PC细胞的致瘤性和转移增加。我们还观察到O-聚糖截断 CC1GALT1模型中的CD44（一种癌症干细胞标记物）中存在。有趣的是，C1GALT1的敲除 小鼠模型中的KRASG12D和TRP53R172H/+突变导致早发（3周内）和早期远处 PC的转移（在10周内）。基于这些观察结果，我们的主要目标是研究机械 截短的O-聚糖在PC进展和转移中的作用。基于这些观察，我们假设 “在癌症相关的糖蛋白（粘蛋白和干性标记）上截断了O-聚糖，诱导了早期 胰腺癌的进展和转移性传播的发作。 提出了目标。第一个目的将研究C1GALT1表达和异常的功能影响 胰腺癌中与癌症相关糖蛋白的糖基化谱。第二个目标将阐明如何 在膜结合的粘蛋白和干燥标记上截短的O-聚糖（例如TN和STN）有助于 胰腺癌转移。第三个目标将在体内确定截短的O-Glycans在早期的影响 使用C1GALT1敲除KC和KPC小鼠的胰腺癌转移发作。拟议的研究将 建立截短TN和STN聚糖异常表达与差异膜的关联 PC进展和转移过程中结合的粘蛋白功能。这项研究将对我们的 癌症糖生物学的知识。总之，这项拟议的研究还将为发展铺平道路 在PC中调节膜结合的粘蛋白功能的新型治疗。