Dysplastic Stem Cell Plasticity Functions as a Driving Force for Neoplastic Transformation of Precancerous Gastric Mucosa

Curzerene suppresses epithelial-mesenchymal transition in gastric precancerous lesion cells through targeted regulation of YAP via the long non-coding RNA AFAP1-AS1

BACKGROUND

Curzerene, a bioactive compound from Curcuma zedoaria, exhibits anticancer effects, but its role in gastric precancerous lesions remains poorly understood. This study investigates the potential of Curzerene in inhibiting gastric precancerous lesions progression by regulating the long non-coding RNA (LncRNA) AFAP1-AS1 and the Hippo/YAP signaling pathway.

METHODS

In vitro, a gastric precancerous cell model (MC cells) was established by treating GES-1 cells with MNNG. The effects of Curzerene on cell proliferation, migration, and EMT were assessed using CCK-8, scratch assays, RT-PCR, and Western blot. In vivo, a gastric precancerous mouse model was induced by MNU, and the therapeutic effects of Curzerene (14 mg/kg and 28 mg/kg) were evaluated through histological and molecular analysis.

RESULTS

Curzerene treatment significantly inhibited MC cell proliferation, migration, and EMT, downregulating LncRNA AFAP1-AS1 and YAP while upregulating E-cadherin and downregulating N-cadherin. In vivo, Curzerene alleviated gastric mucosal damage, reduced cancer markers (P53 and CD133), and improved histopathology. Transcriptomic analysis identified the Hippo/YAP pathway as a key mediator of Curzerene's effects. YAP activation reversed Curzerene's inhibitory effects on EMT, confirming the involvement of this pathway.

CONCLUSION

Curzerene effectively inhibits gastric precancerous lesion progression by targeting the YAP signaling and the following LncRNA AFAP1-AS1 to suppress EMT. These findings suggest Curzerene's novel potential as a promising therapeutic agent for early intervention and prevention of gastric cancer.

Identification of a cancer stem cell-like subpopulation that promotes HCC metastasis

Background & Aims

Cancer stem cells (CSCs) are well-established drivers of tumorigenesis, but their role in regulating tumor metastasis remains poorly understood. Here, we report the identification and characterization of a cluster of metastasis-promoting CSC-like cells in hepatocellular carcinoma (HCC).

Methods

CSC-like cells in HCC were identified through the analysis of single cell RNA-sequencing data from 19 HCC samples. The stemness and invasive characteristics of these cells were evaluated using bioinformatical analyses of nine clinical cohorts and experimental validations. Spatial transcriptomics sequencing of 12 HCC samples revealed the cellular interactions between the CSC-like cells and tumor microenvironments, which were validated through gene co-expression analyses and immunohistochemistry. Finally, signaling pathway blockade was used to assess the potential clinical application of CSC-like cells.

Results

Through comprehensive analyses of single cell RNA-sequencing data from 19 patients with HCC and spatial transcriptomics data from 12 patients with HCC, a metastasis-promoting CSC-like subpopulation was identified. These CSC-like cells expressed high levels of epithelial-mesenchymal transition genes and were associated with poor prognosis of HCC. Histologically, CSC-like cells were enriched in highly aggressive tumors, especially in intrahepatic disseminated foci, where they interacted with immune cells. Functionally, CSC-like cells induced macrophage M2 polarization and T cell exhaustion through the ICAM1 signaling pathway, forming immunosuppressive microenvironments. Downregulation of ICAM1 expression in CSC-like cells suppressed macrophage M2-polarization and T cell exhaustion, thereby reversing antitumor immune effects.

Conclusions

Our study identified a metastasis-promoting CSC subpopulation, providing a potential perspective for CSC-targeted therapies in HCC.

Impact and implications

The heterogeneity of CSCs in HCC has been identified, yet the identification and characterization of metastasis-promoting CSC subpopulations remain unexplored. Here, we identified a CSC-like tumor cell subpopulation that promotes HCC metastasis by increasing cell invasiveness and suppressing antitumor immune responses via the ICAM1 signaling pathway. Our study uncovers novel mechanisms of HCC metastasis from the perspective of CSCs, and proposes potential tumor therapeutic strategies by inhibiting cellular interactions between CSC-like cells and immune cells.

Post-COVID-19 Effects on Chronic Gastritis and Gastric Cellular and Molecular Characteristics in Male Mice

BACKGROUNDS & AIMS

Since the Omicron variant emerged as a major severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant, COVID-19-associated mortality has decreased remarkably. Nevertheless, patients with a history of SARS-CoV-2 infection have been suffering from an aftereffect commonly known as 'long COVID,' affecting diverse organs. However, the effect of SARS-CoV-2 on gastric cells and disease progression was not previously known. We aimed to investigate whether SARS-CoV-2 infection affects stomach cells and if post-COVID-19 conditions can lead to severe gastric disease.

METHODS

Stomach specimens obtained from male K18-hACE2 mice 7 days after SARS-CoV-2 infection were subjected to a transcriptomic analysis for molecular profiling. To investigate the putative role of SARS-CoV-2 in gastric carcinogenesis, K18-hACE2 mice affected by nonlethal COVID-19 were also inoculated with Helicobacter pylori SS1.

RESULTS

Despite the lack of viral dissemination and pathologic traits in the stomach, SARS-CoV-2 infection caused dramatic changes to the molecular profile and some immune subsets in this organ. Notably, the gene sets related to metaplasia and gastric cancer were significantly enriched after viral infection. As a result, chronic inflammatory responses and preneoplastic transitions were promoted in these mice.

CONCLUSION

SARS-CoV-2 infection indirectly leads to profound and post-acute COVID-19 alterations in the stomach at the cellular and molecular levels, resulting in adverse outcomes following co-infection with SARS-CoV-2 and Hpylori. Our results show that 2 prevalent pathogens of humans elicit a negative synergistic effect and provide evidence of the risk of severe chronic gastritis in the post-COVID-19 era.

Advances and global trends of precancerous lesions of gastric cancer: A bibliometric analysis

BACKGROUND

Precancerous lesions of gastric cancer (PLGC) represent a critical pathological stage in the development of intestinal gastric cancer. Early detection and diagnosis are key to reducing the incidence of gastric cancer. Substantial advancements have been made in PLGC research in recent years, making it necessary to provide updated reviews using bibliometric methods. We hypothesize that this review will identify emerging trends, key research areas, and gaps in PLGC research, providing insights that could guide future studies and enhance prevention strategies.

AIM

To comprehensively review the current state of research on PLGC, examining development trends and research hotspots.

METHODS

We conducted a bibliometric analysis of PLGC-related studies published between 2004 and 2023 using the Web of Science Core Collection database. We employed Software, including VOSviewer, CiteSpace, R software, and SCImago Graphica, to map scientific networks and visualize knowledge trends in terms of publication volume, countries/regions, institutions, journals, authors, and keywords.

RESULTS

A total of 4097 articles were included, and overall publication volume showed an increasing trend. Over the past two decades, China published the most articles, followed by the United States, Japan, South Korea, and Italy. Among the top 10 contributors, the United States ranked highest in institutions, authors, and citations and demonstrated the strongest international collaboration. Research keywords in this field were clustered into three main categories: Risk factors, pathogenesis, and diagnosis and treatment. Pathogenesis and molecular biomarkers remain key areas of focus. Future research should explore the mechanisms of gut microbiota, immune microenvironment, metabolic reprogramming, and epigenetics. Advanced technologies, including single-cell sequencing, spatially resolved analysis, multi-omics approaches, artificial intelligence, and machine learning, will likely accelerate in-depth investigations of PLGC.

CONCLUSION

PLGC research has rapidly developed in recent years, gaining considerable attention. This bibliometric analysis reveals research state and emerging trends over the past 20 years, providing insights for future studies.

Cortactin Facilitates Malignant Transformation of Dysplastic Cells in Gastric Cancer Development

BACKGROUND & AIMS

Epithelial cancer onset occurs through sequential stages of cell lineage conversion and functional dysregulation. Dysplasia is a precancerous lesion defined as a direct precursor to cancer and is histologically defined as a transition stage between pre-cancer and cancer, but molecular and biological mechanisms controlling its transformation to malignancy are underdetermined. Here, we discover the crucial role of the actin stabilization and exosome secretion-regulatory protein cortactin in dysplastic cell transformation to adenocarcinoma.

METHODS

We engineered a CRISPR/Cas9-based cortactin knock-out (KO) dysplasia organoid model established from dysplastic tissue and examined malignant roles of cortactin during gastric cancer development in vitro and in vivo.

RESULTS

Although dysplastic cell identity remained unchanged, the cortactin KO organoids exhibited a decrease in cellular organization and multicellular protrusions, which are considered aggressive features when observed in vitro. When injected into the flank of nude mice, cortactin KO cells failed malignant transformation into adenocarcinoma and solid tumor formation with reduced recruitment of fibroblasts and macrophages. In addition, cortactin KO cells showed diminished exosome secretion levels, and adenocarcinoma development was impaired when exosome secretion was inhibited in cortactin wild-type dysplastic cells.

CONCLUSIONS

These data suggest that cortactin is a functional element of membrane dynamics, malignant changes, and exosome secretion in dysplastic cells, and solid gastric tumor formation associated with alteration of the tumor microenvironment.

p53 mutation biases squamocolumnar junction progenitor cells towards dysplasia rather than metaplasia in Barrett's oesophagus

BACKGROUND

While p53 mutations occur early in Barrett's oesophagus (BE) progression to oesophageal adenocarcinoma (EAC), their role in gastric cardia stem cells remains unclear.

OBJECTIVE

This study investigates the impact of p53 mutation on the fate and function of cardia progenitor cells in BE to EAC progression, particularly under the duress of chronic injury.

DESIGN

We used a BE mouse model (L2-IL1β) harbouring a Trp53 mutation (R172H) to study the effects of p53 on Cck2r+ cardia progenitor cells. We employed lineage tracing, pathological analysis, organoid cultures, single-cell RNA sequencing (scRNA-seq) and computational analyses to investigate changes in progenitor cell behaviour, differentiation patterns and tumour progression. Additionally, we performed orthotopic transplantation of sorted metaplastic and mutant progenitor cells to assess their tumourigenic potential in vivo.

RESULTS

The p53 mutation acts as a switch to expand progenitor cells and inhibit their differentiation towards metaplasia, but only amidst chronic injury. In L2-IL1β mice, p53 mutation increased progenitors expansion and lineage-tracing with a shift from metaplasia to dysplasia. scRNA-seq revealed dysplastic cells arise directly from mutant progenitors rather than progressing through metaplasia. In vitro, p53 mutation enhanced BE progenitors' organoid-forming efficiency, growth, DNA damage resistance and progression to aneuploidy. Sorted metaplastic cells grew poorly with no progression to dysplasia, while mutant progenitors gave rise to dysplasia in orthotopic transplantation. Computational analyses indicated that p53 mutation inhibited stem cell differentiation through Notch activation.

CONCLUSIONS

p53 mutation contributes to BE progression by increasing expansion and fitness of undifferentiated cardia progenitors and preventing their differentiation towards metaplasia.

Emerging strategies to investigate the biology of early cancer

Early detection and intervention of cancer or precancerous lesions hold great promise to improve patient survival. However, the processes of cancer initiation and the normal-precancer-cancer progression within a non-cancerous tissue context remain poorly understood. This is, in part, due to the scarcity of early-stage clinical samples or suitable models to study early cancer. In this Review, we introduce clinical samples and model systems, such as autochthonous mice and organoid-derived or stem cell-derived models that allow longitudinal analysis of early cancer development. We also present the emerging techniques and computational tools that enhance our understanding of cancer initiation and early progression, including direct imaging, lineage tracing, single-cell and spatial multi-omics, and artificial intelligence models. Together, these models and techniques facilitate a more comprehensive understanding of the poorly characterized early malignant transformation cascade, holding great potential to unveil key drivers and early biomarkers for cancer development. Finally, we discuss how these new insights can potentially be translated into mechanism-based strategies for early cancer detection and prevention.

Streptococcus anginosus in the development and treatment of precancerous lesions of gastric cancer

The microbiota is strongly association with cancer. Studies have shown significant differences in the gastric microbiota between patients with gastric cancer (GC) patients and noncancer patients, suggesting that the microbiota may play a role in the development of GC. Although Helicobacter pylori (H. pylori) infection is widely recognized as a primary risk factor for GC, recent studies based on microbiota sequencing technology have revealed that non-H. pylori microbes also have a significant impact on GC. A recent study discovered that Streptococcus anginosus (S. anginosus) is more prevalent in the gastric mucosa of patients with GC than in that of those without GC. S. anginosus infection can spontaneously induce chronic gastritis, mural cell atrophy, mucoid chemotaxis, and heterotrophic hyperplasia, which promote the development of precancerous lesions of GC (PLGC). S. anginosus also disrupts the gastric barrier function, promotes the proliferation of GC cells, and inhibits apoptosis. However, S. anginosus is underrepresented in the literature. Recent reports suggest that it may cause precancerous lesions, indicating its emerging pathogenicity. Modern novel molecular diagnostic techniques, such as polymerase chain reaction, genetic testing, and Ultrasensitive Chromosomal Aneuploidy Detection, can be used to gastric precancerous lesions via microbial markers. Therefore, we present a concise summary of the relationship between S. anginosus and PLGC. Our aim was to further investigate new methods of preventing and treating PLGC by exploring the pathogenicity of S. anginosus on PLGC.

Hyaluronic acid metabolism and chemotherapy resistance: recent advances and therapeutic potential

Hyaluronic acid (HA) is a major component of the extracellular matrix, providing essential mechanical scaffolding for cells and, at the same time, mediating essential biochemical signals required for tissue homeostasis. Many solid tumors are characterized by dysregulated HA metabolism, resulting in increased HA levels in cancer tissues. HA interacts with several cell surface receptors, such as cluster of differentiation 44 and receptor for hyaluronan-mediated motility, thus co-regulating important signaling pathways in cancer development and progression. In this review, we describe the enzymes controlling HA metabolism and its intracellular effectors emphasizing their impact on cancer chemotherapy resistance. We will also explore the current and future prospects of HA-based therapy, highlighting the opportunities and challenges in the field.

Personalized drug screening using patient-derived organoid and its clinical relevance in gastric cancer

The efficacy of chemotherapy varies significantly among patients with gastric cancer (GC), and there is currently no effective strategy to predict chemotherapeutic outcomes. In this study, we successfully establish 57 GC patient-derived organoids (PDOs) from 73 patients with GC (78%). These organoids retain histological characteristics of their corresponding primary GC tissues. GC PDOs show varied responses to different chemotherapeutics. Through RNA sequencing, the upregulation of tumor suppression genes/pathways is identified in 5-fluorouracil (FU)- or oxaliplatin-sensitive organoids, whereas genes/pathways associated with proliferation and invasion are enriched in chemotherapy-resistant organoids. Gene expression biomarker panels, which could distinguish sensitive and resistant patients to 5-FU and oxaliplatin (area under the dose-response curve [AUC] >0.8), are identified. Moreover, the drug-response results in PDOs are validated in patient-derived organoids-based xenograft (PDOX) mice and are consistent with the actual clinical response in 91.7% (11/12) of patients with GC. Assessing chemosensitivity in PDOs can be utilized as a valuable tool for screening chemotherapeutic drugs in patients with GC.

Oncogenic Fatty Acid Metabolism Rewires Energy Supply Chain in Gastric Carcinogenesis

BACKGROUND & AIMS

Gastric carcinogenesis develops within a sequential carcinogenic cascade from precancerous metaplasia to dysplasia and adenocarcinoma, and oncogenic gene activation can drive the process. Metabolic reprogramming is considered a key mechanism for cancer cell growth and proliferation. However, how metabolic changes contribute to the progression of metaplasia to dysplasia remains unclear. We have examined metabolic dynamics during gastric carcinogenesis using a novel mouse model that induces Kras activation in zymogen-secreting chief cells.

METHODS

We generated a Gif-rtTA;TetO-Cre;KrasG12D (GCK) mouse model that continuously induces active Kras expression in chief cells after doxycycline treatment. Histologic examination and imaging mass spectrometry were performed in the GCK mouse stomachs at 2 to 14 weeks after doxycycline treatment. Mouse and human gastric organoids were used for metabolic enzyme inhibitor treatment. The GCK mice were treated with a stearoyl- coenzyme A desaturase (SCD) inhibitor to inhibit the fatty acid desaturation. Tissue microarrays were used to assess the SCD expression in human gastrointestinal cancers.

RESULTS

The GCK mice developed metaplasia and high-grade dysplasia within 4 months. Metabolic reprogramming from glycolysis to fatty acid metabolism occurred during metaplasia progression to dysplasia. Altered fatty acid desaturation through SCD produces a novel eicosenoic acid, which fuels dysplastic cell hyperproliferation and survival. The SCD inhibitor killed both mouse and human dysplastic organoids and selectively targeted dysplastic cells in vivo. SCD was up-regulated during carcinogenesis in human gastrointestinal cancers.

CONCLUSIONS

Active Kras expression only in gastric chief cells drives the full spectrum of gastric carcinogenesis. Also, oncogenic metabolic rewiring is an essential adaptation for high-energy demand in dysplastic cells.

The Hallmarks of Precancer

Research on precancers, as defined as at-risk tissues and early lesions, is of high significance given the effectiveness of early intervention. We discuss the need for risk stratification to prevent overtreatment, an emphasis on the role of genetic and epigenetic aging when considering risk, and the importance of integrating macroenvironmental risk factors with molecules and cells in lesions and at-risk normal tissues for developing effective intervention and health policy strategies.

Integration of single-cell transcriptome and chromatin accessibility and its application on tumor investigation

The advent of single-cell sequencing techniques has not only revolutionized the investigation of biological processes but also significantly contributed to unraveling cellular heterogeneity at unprecedented levels. Among the various methods, single-cell transcriptome sequencing stands out as the best established, and has been employed in exploring many physiological and pathological activities. The recently developed single-cell epigenetic sequencing techniques, especially chromatin accessibility sequencing, have further deepened our understanding of gene regulatory networks. In this review, we summarize the recent breakthroughs in single-cell transcriptome and chromatin accessibility sequencing methodologies. Additionally, we describe current bioinformatic strategies to integrate data obtained through these single-cell sequencing methods and highlight the application of this analysis strategy on a deeper understanding of tumorigenesis and tumor progression. Finally, we also discuss the challenges and anticipated developments in this field.

Insights into optimizing exosome therapies for acute skin wound healing and other tissue repair

Exosome therapy holds great promise as a novel approach to improve acute skin wound healing. This review provides a comprehensive overview of the current understanding of exosome biology and its potential applications in acute skin wound healing and beyond. Exosomes, small extracellular vesicles secreted by various stem cells, have emerged as potent mediators of intercellular communication and tissue repair. One advantage of exosome therapy is its ability to avoid potential risks associated with stem cell therapy, such as immune rejection or stem cells differentiating into unwanted cell types. However, further research is necessary to optimize exosome therapy, not only in the areas of exosome isolation, characterization, and engineering, but also in determining the optimal dose, timing, administration, and frequency of exosome therapy. Thus, optimization of exosome therapy is critical for the development of more effective and safer exosome-based therapies for acute skin wound healing and other diseases induced by cancer, ischemia, or inflammation. This review provides valuable insights into the potential of exosome therapy and highlights the need for further research to optimize exosome therapy for clinical use.

Gastric intestinal metaplasia: progress and remaining challenges

Most gastric cancers arise in the setting of chronic inflammation which alters gland organization, such that acid-pumping parietal cells are lost, and remaining cells undergo metaplastic change in differentiation patterns. From a basic science perspective, recent progress has been made in understanding how atrophy and initial pyloric metaplasia occur. However, pathologists and cancer biologists have long been focused on the development of intestinal metaplasia patterns in this setting. Arguably, much less progress has been made in understanding the mechanisms that lead to the intestinalization seen in chronic atrophic gastritis and pyloric metaplasia. One plausible explanation for this disparity lies in the notable absence of reliable and reproducible small animal models within the field, which would facilitate the investigation of the mechanisms underlying the development of gastric intestinal metaplasia (GIM). This review offers an in-depth exploration of the current state of research in GIM, shedding light on its pivotal role in tumorigenesis. We delve into the histological subtypes of GIM and explore their respective associations with tumor formation. We present the current repertoire of biomarkers utilized to delineate the origins and progression of GIM and provide a comprehensive survey of the available, albeit limited, mouse lines employed for modeling GIM and engage in a discussion regarding potential cell lineages that serve as the origins of GIM. Finally, we expound upon the myriad signaling pathways recognized for their activity in GIM and posit on their potential overlap and interactions that contribute to the ultimate manifestation of the disease phenotype. Through our exhaustive review of the progression from gastric disease to GIM, we aim to establish the groundwork for future research endeavors dedicated to elucidating the etiology of GIM and developing strategies for its prevention and treatment, considering its potential precancerous nature.

Targeting Stem Cells and Dysplastic Features With Dual MEK/ERK and STAT3 Suppression in Gastric Carcinogenesis

BACKGROUNDS & AIMS

Precancerous metaplasia progression to dysplasia can increase the risk of gastric cancers. However, effective strategies to specifically target these precancerous lesions are currently lacking. To address this, we aimed to identify key signaling pathways that are upregulated during metaplasia progression and critical for stem cell survival and function in dysplasia.

METHODS

To assess the response to chemotherapeutic drugs, we used metaplastic and dysplastic organoids derived from Mist1-Kras mice and 20 human precancerous organoid lines established from patients with gastric cancer. Phospho-antibody array analysis and single-cell RNA-sequencing were performed to identify target cell populations and signaling pathways affected by pyrvinium, a putative anticancer drug. Pyrvinium was administered to Mist1-Kras mice to evaluate drug effectiveness in vivo.

RESULTS

Although pyrvinium treatment resulted in growth arrest in metaplastic organoids, it induced cell death in dysplastic organoids. Pyrvinium treatment significantly downregulated phosphorylation of ERK and signal transducer and activator of transcription 3 (STAT3) as well as STAT3-target genes. Single-cell RNA-sequencing data analyses revealed that pyrvinium specifically targeted CD133+/CD166+ stem cell populations, as well as proliferating cells in dysplastic organoids. Pyrvinium inhibited metaplasia progression and facilitated the restoration of normal oxyntic glands in Mist1-Kras mice. Furthermore, pyrvinium exhibited suppressive effects on the growth and survival of human organoids with dysplastic features, through simultaneous blocking of the MEK/ERK and STAT3 signaling pathways.

CONCLUSIONS

Through its dual blockade of MEK/ERK and STAT3 signaling pathways, pyrvinium can effectively induce growth arrest in metaplasia and cell death in dysplasia. Therefore, our findings suggest that pyrvinium is a promising chemotherapeutic agent for reprogramming the precancerous milieu to prevent gastric cancer development.

Dynamic tuft cell expansion during gastric metaplasia and dysplasia

Tuft cells are chemosensory cells associated with luminal homeostasis, immune response, and tumorigenesis in the gastrointestinal tract. We aimed to elucidate alterations in tuft cell populations during gastric atrophy and tumorigenesis in humans with correlative comparison to relevant mouse models. Tuft cell distribution was determined in human stomachs from organ donors and in gastric pathologies including Ménétrier's disease, Helicobacter pylori gastritis, intestinal metaplasia (IM), and gastric tumors. Tuft cell populations were examined in Lrig1-KrasG12D , Mist1-KrasG12D , and MT-TGFα mice. Tuft cells were evenly distributed throughout the entire normal human stomach, primarily concentrated in the isthmal region in the fundus. Ménétrier's disease stomach showed increased tuft cells. Similarly, Lrig1-Kras mice and mice overexpressing TGFα showed marked foveolar hyperplasia and expanded tuft cell populations. Human stomach with IM or dysplasia also showed increased tuft cell numbers. Similarly, Mist1-Kras mice had increased numbers of tuft cells during metaplasia and dysplasia development. In human gastric cancers, tuft cells were rarely observed, but showed positive associations with well-differentiated lesions. In mouse gastric cancer xenografts, tuft cells were restricted to dysplastic well-differentiated mucinous cysts and were lost in less differentiated cancers. Taken together, tuft cell populations increased in atrophic human gastric pathologies, metaplasia, and dysplasia, but were decreased in gastric cancers. Similar findings were observed in mouse models, suggesting that, while tuft cells are associated with precancerous pathologies, their loss is most associated with the progression to invasive cancer.

The composition and roles of gastric stem cells in epithelial homeostasis, regeneration, and tumorigenesis

The epithelial lining of the stomach undergoes rapid turnover to preserve its structural and functional integrity, a process driven by long-lived stem cells residing in the antral and corpus glands. Several subpopulations of gastric stem cells have been identified and their phenotypic and functional diversities linked to spatiotemporal specification of stem cells niches. Here, we review the biological features of gastric stem cells at various locations of the stomach under homeostatic conditions, as demonstrated by reporter mice, lineage tracing, and single cell sequencing. We also review the role of gastric stem cells in epithelial regeneration in response to injury. Moreover, we discuss emerging evidence demonstrating that accumulation of oncogenic drivers or alteration of stemness signaling pathways in gastric stem cells promotes gastric cancer. Given a fundamental role of the microenvironment, this review highlights the role reprogramming of niche components and signaling pathways under pathological conditions in dictating stem cell fate. Several outstanding issues are raised, such as the relevance of stem cell heterogeneity and plasticity, and epigenetic regulatory mechanisms, to Helicobacter pylori infection-initiated metaplasia-carcinogenesis cascades. With the development of spatiotemporal genomics, transcriptomics, and proteomics, as well as multiplexed screening and tracing approaches, we anticipate that more precise definition and characterization of gastric stem cells, and the crosstalk with their niche will be delineated in the near future. Rational exploitation and proper translation of these findings may bring forward novel modalities for epithelial rejuvenation and cancer therapeutics.

Organoid cultures for cancer modeling

Organoids derived from adult stem cells (ASCs) and pluripotent stem cells (PSCs) are important preclinical models for studying cancer and developing therapies. Here, we review primary tissue-derived and PSC-derived cancer organoid models and detail how they have the potential to inform personalized medical approaches in different organ contexts and contribute to the understanding of early carcinogenic steps, cancer genomes, and biology. We also compare the differences between ASC- and PSC-based cancer organoid systems, discuss their limitations, and highlight recent improvements to organoid culture approaches that have helped to make them an even better representation of human tumors.

Spasmolytic polypeptide-expressing metaplasia (SPEM) cell lineages can be an origin of gastric cancer

Intestinal-type gastric cancer arises in a field of precancerous metaplastic lineages. Two types of metaplastic glands are found in the stomachs of humans with the characteristics of pyloric metaplasia or intestinal metaplasia. While spasmolytic polypeptide-expressing metaplasia (SPEM) cell lineages have been identified in both pyloric metaplasia and incomplete intestinal metaplasia, it has been unclear whether SPEM lineages or intestinal lineages can give rise to dysplasia and cancer. A recent article published in The Journal of Pathology describes a patient with evidence of an activating Kras(G12D) mutation in SPEM that is propagated into adenomatous and cancerous lesions which manifest further oncogenic mutations. This case therefore supports the concept that SPEM lineages can serve as a direct precursor for dysplasia and intestinal-type gastric cancer. © 2023 The Pathological Society of Great Britain and Ireland.

3'-sulfated LewisA/C: An oncofetal epitope associated with metaplastic and oncogenic plasticity of the gastrointestinal foregut

Metaplasia, dysplasia, and cancer arise from normal epithelia via a plastic cellular transformation, typically in the setting of chronic inflammation. Such transformations are the focus of numerous studies that strive to identify the changes in RNA/Protein expression that drive such plasticity along with the contributions from the mesenchyme and immune cells. However, despite being widely utilized clinically as biomarkers for such transitions, the role of glycosylation epitopes is understudied in this context. Here, we explore 3'-Sulfo-Lewis A/C, a clinically validated biomarker for high-risk metaplasia and cancer throughout the gastrointestinal foregut: esophagus, stomach, and pancreas. We discuss the clinical correlation of sulfomucin expression with metaplastic and oncogenic transformation, as well as its synthesis, intracellular and extracellular receptors and suggest potential roles for 3'-Sulfo-Lewis A/C in contributing to and maintaining these malignant cellular transformations.

Pyrvinium Pamoate: Past, Present, and Future as an Anti-Cancer Drug

Pyrvinium, a lipophilic cation belonging to the cyanine dye family, has been used in the clinic as a safe and effective anthelminthic for over 70 years. Its structure, similar to some polyaminopyrimidines and mitochondrial-targeting peptoids, has been linked with mitochondrial localization and targeting. Over the past two decades, increasing evidence has emerged showing pyrvinium to be a strong anti-cancer molecule in various human cancers in vitro and in vivo. This efficacy against cancers has been attributed to diverse mechanisms of action, with the weight of evidence supporting the inhibition of mitochondrial function, the WNT pathway, and cancer stem cell renewal. Despite the overwhelming evidence demonstrating the efficacy of pyrvinium for the treatment of human cancers, pyrvinium has not yet been repurposed for the treatment of cancers. This review provides an in-depth analysis of the history of pyrvinium as a therapeutic, the rationale and data supporting its use as an anticancer agent, and the challenges associated with repurposing pyrvinium as an anti-cancer agent.