Esophageal cancer is the 7th common cancer with the 6th highest cancer mortality rate worldwide. The 5-year survival rate of esophageal cancer is 10 ~ 25%. Esophageal cancer is mainly divided into esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma. ESCC accounts for 80% of all esophageal cancer cases and shows a poor prognosis due to a lack of symptoms at early stages. Given that early diagnosis of ESCC may lead to better outcomes, understanding the biology of ESCC initiation is imperative. To recapitulate the early events of ESCC, we employed the murine esophageal organoid (EO) system recently developed. Based on in silico analyses, we selected nine candidate genes (TP53, CDKN2A, NOTCH1, NOTCH3, KMT2D, KMT2C, FAT1, FAT4, and AJUBA) frequently mutated in ESCC patients. The EOs were then genetically manipulated with the combinatorial ablation of nine genes by CRISPR/Cas9 system. The EOs carrying PN (Trp53 and Notch1 KO), PC (Trp53 and Cdkn2a KO), and PCN (Trp53, Cdkn2a, and Notch1 KO) showed hyperplastic and neoplastic properties with impaired squamous cell differentiation and organoid integrity, compared to the wild-type (WT) EOs. Single-cell RNA-seq (scRNA-seq) analyses of WT, PC, PN, and PCN organoids showed the highest enrichment of ESCC cancer stem cell markers in PCN organoids. Unlike the cell lineage in WT EOs, neoplastic EOs (PC, PN, and PCN) exhibited distinct cell lineage along with multiple root cell clusters. While WT EOs failed to become neoplastic, PN, PC, and PCN EOs displayed the transforming activity in vitro and in vivo xenograft transplantation assays. Intriguingly, in allograft mouse models, while PN organoids-derived cells barely developed tumors, PC and PCN organoids-derived cells developed tumors with marked downregulation of genes related to antigen processing and presentation. These results suggest that combinatorial loss of P53, CDKN2A, and NOTCH1 play a pivotal role in ESCC neoplasia, stemness, and immune checkpoint, unveiling the biology of ESCC initiation. Citation Format: Kyung Pil Ko, Gengyi Zou, Yuanjian Huang, Bongjun Kim, Jie Zhang, Sohee Jun, Jae-Il Park. Modeling and dissecting of esophageal squamous cell carcinoma initiation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 943.
Gastric cancer (GC) is the third most common cancer and the second most common cause of cancer death in Asia. The highest incidence rates are observed in Eastern Asia. To date, the comprehensive mechanism of GC initiation remains elusive. Here, we discovered CRACD (Capping Protein Inhibiting Regulator of Actin Dynamics/CRAD/KIAA1211) as a tumor suppressor, frequently inactivated in GC. To determine the pathologic roles of CRACD, we employed Cracd knock-out (KO) mice and gastric organoids (GOs). Intriguingly, Cracd KO mice and GOs displayed hyperplastic gastric epithelium. Mechanistically, CRACD is essential for stabilizing the cadherin-catenin-actin (CCA) complex. The loss of CRACD leads to the release and nuclear translocation of β-catenin for Wnt target gene transactivation. Indeed, the genetic ablation of Cracd hyperactivated Wnt/β-catenin signaling with the disruption of the CCA complex. The genes encoding the Receptor Tyrosine Kinase (RTK)-RAS signaling pathway and the TP53 are genetically altered in 60% and 50% of gastric adenocarcinomas, respectively. To define the genetic interaction of Cracd loss with the RTK-RAS and TP53 signaling, we established genetically engineered GOs models carrying Trp53 deletion and KrasG12D activation in combination with Cracd KO (CKP) or Cracd wild type (KP). Compared to KP, CKP GOs exhibited neoplasia, higher mucin deposition, and increased carcinoma embryonic antigen (CEA) expression, pathologically related to the poor prognosis in GC patients. Meanwhile, loss of Cracd significantly accelerated the growth of CKP GOs with increased stemness. Furthermore, the CKP cell line derived from GOs exhibited relatively poor prognosis features of GC than KP cells in the xenograft models, represented by boosted tumor size and weight, poor differentiation, hyperplasia, increased CEA, and mucin secretion. Together, we identified CRACD as a tumor suppressor, of which inactivation contributes to GC initiation and progression, which may be translated into the development of a biomarker-guided regimen for CRACD mutations-associated GC patients. Citation Format: Gengyi Zou, Yuanjian Huang, Kyung Pil Ko, Shengzhe Zhang, Bong Jun Kim, Jie Zhang, Sohee Jun, Youn-Sang Jung, Biyun Zheng, Jae-Il Park. CRACD/CRAD, a tumor suppressor for gastric cancer development [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 836.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.