Abstract B099: Aberrant glycosylation in pancreatic ductal adenocarcinoma 3D organoids is mediated by KRAS mutations
Authors: Nakahashi Hiromitsu , Oda Tatsuya , Shimomura Osamu , Akashi Yoshimasa , Takahashi Kazuhiro , Miyazaki Yoshihiro , Furuta Tomoaki , Kuroda Yukihito , Louphrasitthiphol Pakavarin , Mathis Bryan J. , Tateno Hiroaki 
Published: January 2024

Abstract
Introduction: Aberrant glycosylation in tumor cells is a hallmark during carcinogenesis. Moreover, as glycans constitute the outermost layer of cells, diverse alterations during carcinogenesis affect the multiple processes of invasion and metastasis, making glycosylation a keystone mechanism in cancer progression. KRAS gene mutations are the most well-known oncogenic abnormalities but their association with glycan alterations in pancreatic ductal adenocarcinoma (PDAC) is largely unknown. We employed patient-derived 3D organoids to culture pure live PDAC cells, excluding contamination by fibroblasts and immune cells for comprehensive cell surface glycan expression profile using lectin microarray and transcriptomic analyses and then analyzed the relationship between altered glycans and glycan-related genes, with a particular focus on the status of KRAS mutations. Materials and methods: Surgical specimens from 24 PDAC patients were digested and embedded into a 3D culture system containing extracellular matrix and specific niche factors. Surface-bound glycans of 3D organoids were analyzed by high-density, 96-lectin microarrays. KRAS mutation status and expression of various glycosyltransferases were analyzed by RNA-seq. Results: We successfully established 16 3D-organoids: 14 PDAC, 1 intraductal papillary mucinous neoplasm (IPMN), and 1 normal pancreatic duct. KRAS mutations (7 G12V, 5 G12D, 1 Q61L) were found in 13 organoids, while wild-type KRAS without mutations was detected in 3 organoids (1 normal duct, 1 IPMN, 1 PDAC). Pairings of a PDAC organoid with a non-PDAC counterpart were available from 2 patients; one was a PDAC-normal MPD pair and the other was PDAC-IPMN pair, eliminating the influence of individual variations in glycan expression status for those pairs. Lectin reactivity of AAL and AOL with binding activity to α1-3 fucose was higher in organoids with KRAS mutants than those with KRAS wild-type. FUT6 (α1-3fucosyltransferase 6) and FUT3 (α1-3/4 fucosyltransferase 3) expression was also higher in KRAS mutants than wild-type. And also, in the two cases with PDAC and non-PDAC organoids pairs, the reactivity of AAL were significantly elevated in the KRAS mutants, with FUT6 and FUT3 elevated. Conclusion: PDAC 3D-cultured organoids with KRAS mutations were covered in increased fucosylated glycans, pointing towards novel treatment targets and/or tumor markers.
Citation Format: Hiromitsu Nakahashi, Tatsuya Oda, Osamu Shimomura, Yoshimasa Akashi, Kazuhiro Takahashi, Yoshihiro Miyazaki, Tomoaki Furuta, Yukihito Kuroda, Pakavarin Louphrasitthiphol, Bryan J. Mathis, Hiroaki Tateno. Aberrant glycosylation in pancreatic ductal adenocarcinoma 3D organoids is mediated by KRAS mutations [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr B099.