Mucin Phenotype Research Articles

Ki-67 distribution, α-methylacyl-CoA racemase (AMACR) expression and mucin phenotypes are associated with non-polypoid growth in ulcerative colitis-associated neoplasia.

Ulcerative colitis-associated neoplasia (UCAN) is characterised by multifocal tumourigenesis. A wide range of metachronous lesions have been reported to occur after endoscopic treatment of UCAN, which suggests the development of sporadic tumours in lesions treated as UCAN. Therefore, we aimed to evaluate differences of immunohistochemistry (IHC) in features and clinicopathological characteristics of intramucosal lesions in patients with ulcerative colitis (UC). We examined 35 intramucosal lesions resected for carcinoma or dysplasia by total colectomy from patients with UC and 71 sporadic adenomas (SAs) endoscopically resected from patients without UC. UC lesions were divided into the conventional UCAN group, defined as p53 mutant pattern andnormal expression of β-catenin, and the non-conventional UCAN group, defined as the rest. Ki-67 distribution, α-methylacyl-CoA racemase (AMACR) expression and mucin phenotypes were compared using IHC, and clinicopathological characteristics were investigated. Conventional and non-conventional UCAN lesions were located in the left colon and rectum. Relative to the SA lesions, UCAN lesions occurred in much younger patients and exhibited more frequent basal distribution of Ki-67 in tumour crypts. Conventional UCAN lesions tended to be non-polyploid and exhibited a higher frequency of normal AMACR expression than SA lesions. UC lesions were heterogeneous-only two of the eight patients with multiple lesions had lesions (both non-conventional UCAN lesions) exhibiting concordant IHC staining features. The basal pattern of Ki-67 distribution, normal expression of AMACR and a non-intestinal mucin phenotype were determined as characteristic features suggestive of UCAN. Non-polypoid growth was another a key feature of UCAN.

Molecular and Clinicopathologic Impact of GNAS Variants Across Solid Tumors.

The molecular drivers underlying mucinous tumor pathogenicity are poorly understood. GNAS mutations predict metastatic burden and treatment resistance in mucinous appendiceal adenocarcinoma. We investigated the pan-cancer clinicopathologic relevance of GNAS variants. We assessed 58,043 patients with Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (IMPACT)-sequenced solid tumors to identify oncogenic variants, including GNAS, associated with mucinous tumor phenotype. We then performed comprehensive molecular analyses to compare GNAS-mutant (mut) and wild-type tumors across cancers. Gene expression patterns associated with GNAS-mut tumors were assessed in a The Cancer Genome Atlas cohort. Associations between GNAS variant status and peritoneal metastasis, first-line systemic therapy response, progression-free survival (PFS), and overall survival (OS) were determined using a propensity-matched subcohort of patients with metastatic disease. Mucinous tumors were enriched for oncogenic GNAS variants. GNAS was mutated in >1% of small bowel, cervical, colorectal, pancreatic, esophagogastric, hepatobiliary, and GI neuroendocrine cancers. Across these cancers, GNAS-mut tumors exhibited a generally conserved C-to-T mutation-high, aneuploidy-low molecular profile with co-occurring prevalent KRAS variants (65% of GNAS-mut tumors) and fewer TP53 alterations. GNAS-mut tumors exhibited recurrently comutated alternative tumor suppressors (RBM10, INPPL1) and upregulation of MAPK and cell surface modulators. GNAS-mut tumors demonstrate an increased prevalence of peritoneal metastases (odds ratio [OR], 1.7 [95% CI, 1.1 to 2.5]; P = .006), worse response to first-line systemic therapy (OR, 2.2 [95% CI, 1.3 to 3.8]; P = .003), and shorter PFS (median, 5.6 v 7.0 months; P = .047). In a multivariable analysis, GNAS mutated status was independently prognostic of worse OS (hazard ratio, 1.25 [95% CI, 1.01 to 1.56]; adjusted P = .04). Across the assessed cancers, GNAS-mut tumors exhibit a conserved molecular and clinical phenotype defined by mucinous tumor status, increased peritoneal metastasis, poor response to first-line systemic therapy, and worse survival.

Initial Tumor Size and Narrow-Band Image Findings Estimate Growth Speed in Duodenal Tumors.

Recently, the detection of superficial non-ampullary duodenal epithelial tumors (SNADETs) including adenomas and superficial duodenal carcinomas has increased. Various endoscopic treatment methods have also been reported for SNADETs, but there are few reports on the natural history. The aim of this study was to analyze factors related to tumor growth and determine the characteristics of SNADETs which need early therapeutic intervention. A single-center, retrospective study was performed on the medical records of 309 patients with SNADETs who underwent endoscopic or surgical resection between January 2010 and May 2021. Of these, 41 patients who were followed up for more than 1 year by endoscopy were analyzed. The primary outcome was an analysis of the tumor growth speed. Secondary outcomes were the relationship between the tumor growth speed and mucin phenotype, tumor size and findings of magnifying endoscopy with narrow-band imaging (M-NBI). The observation period was 24 months (13-182). Tumor growth speed was 1.1 mm/year (0-21.6). Tumor diameter ≥10 mm at first detection (p = 0.004; odds ratio 19.5 [2.03-186.96]) and mixed type by M-NBI (p = 0.036; odds ratio 9.69 [1.05-89.88]) were identified as risk factors of tumors growing at a rate of ≥3 mm/year. There was no statistically significant difference in the speed of tumor growth between the different mucin immunohistochemical phenotypes. Initial tumor size and findings of M-NBI are useful to predict tumor growth and consider early intervention.

Sporadic non-ampullary duodenal adenoma with high grade dysplasia: A rare case report

Duodenal adenomatous polyps are usually classified according to the mucin phenotype into intestinal (89.1%) and gastric type (10.9%). The intestinal-type polyps are morphologically divided into tubular and tubulo-villous adenomas, whereas the gastric-type into pyloric gland adenomas and foveolar adenomas. The duodenal adenomas are also clinically categorised into sporadic duodenal adenomas and adenomas associated with genetic syndromes for instance familial adenomatous polyposis (FAP), or MUTYH associated adenomatous polyposis (MAP). Sporadic duodenal adenomas are less common than FAP related adenomas and are usually recognized in elderly men in their 6 to 8 decade of life. The large non-ampullary solitary duodenal adenomas ≥ 20 mm in diameter with high grade dysplasia show a significantly high risk of progression to adenocarcinoma and therefore, must be treated immediately. Our case, is a middle-aged female who presented with symptoms and had an exophytic duodenal mass of about 60mm in diameter, microscopically showing tubulo-villous intestinal pattern with high grade dysplasia and no breach in muscularis mucosae, thereby making it a case with distinct presentation and characteristics.

A Rare Case of Signet Ring Cell Carcinoma Arising on Duodenal Brunner’s Gland Hyperplasia Successfully Treated Via Endoscopic Resection

Signet-ring cell carcinoma (SRCC) is a rare tumor that most commonly occurs in the stomach. Duodenal SRCCs are extremely uncommon and account for approximately 1% of duodenal adenocarcinomas. Although Brunner’s gland hyperplasia (BGH) is a benign duodenal condition, studies have reported several cases of adenocarcinoma originating in an area of BGH. We report a rare case of early-stage SRCC originating in an area of BGH that was successfully treated using endoscopic mucosal resection. Based on the mucin phenotype observed in this case, it is reasonable to conclude that SRCC originated from gastric metaplasia in the area of BGH. Although BGH is a benign condition, careful evaluation is warranted for early detection of combined neoplasms.

Mucin phenotype and microvessels in early gastic cancer: Magnifying endoscopy with narrow band imaging

BackgroundsIn order to detect early gastric cancer (EGC), this research sought to assess the diagnostic utility of magnifying endoscopy (ME) as well as the significance of mucin phenotype and microvessel features. Methods402 individuals with an EGC diagnosis underwent endoscopic submucosal dissection (ESD) at the Department of ME between 2012 and 2020. After adjusting for image distortion, high-magnification endoscopic pictures were taken and examined to find microvessels in the area of interest. The microvessel density was measured as counts per square millimeter (counts/mm2) after segmentation, and the vascular bed's size was computed as a percentage of the area of interest. To identify certain properties of the microvessels, such as end-points, crossing points, branching sites, and connection points, further processing was done using skeletonized pixels. ResultsAccording to the research, undifferentiated tumors often lacked the MS pattern and showed an oval and tubular microsurface (MS) pattern, but differentiated EGC tumors usually lacked the MS pattern and presented a corkscrew MV pattern. Submucosal invasion was shown to be more strongly associated with the destructive MS pattern in differentiated tumors as opposed to undifferentiated tumors. While lesions with a corkscrew MV pattern and an antrum or body MS pattern revealed greater MUC5AC expression, lesions with a loop MV pattern indicated higher MUC2 expression. Furthermore, CD10 expression was higher in lesions with a papillary pattern and an antrum or body MS pattern. ConclusionThese results imply that evaluating mucin phenotype and microvessel features in conjunction with magnifying endoscopy (ME) may be a useful diagnostic strategy for early gastric cancer (EGC) detection. Nevertheless, further investigation is required to confirm these findings and identify the best course of action for EGC diagnosis.

Oncogenic GNAS drives a pyloric-type transcriptomic program in pancreatic intraepithelial papillary mucinous neoplasms

BACKGROUND & AIMS: Intraductal Papillary Mucinous Neoplasms (IPMNs) are cystic lesions of the pancreas which can serve as precursors for pancreatic ductal adenocarcinoma (PDAC). Recently, we showed that acinar to ductal metaplasia (ADM), an injury repair program associated with pancreatic tumorigenesis, is characterized by a pyloric-type transcriptomic program similar to gastric spasmolytic polypeptide expressing metaplasia (SPEM), suggesting common mechanisms of reprogramming between the stomach and pancreas. The aims of this study were to assay IPMN for SPEM markers and to identify molecular drivers of this program. METHODS: Published RNA-seq studies of IPMN were assessed for SPEM markers, which were validated by immunostaining in patient samples. Murine cell lines expressing KrasG12D +/- GNASR201C were manipulated to identify distinct and overlapping transcriptomic programs driven by each oncogene. A PyScenic-based regulon analysis was performed to identify drivers of SPEM in the pancreas. Expression of candidate drivers was evaluated in patient samples by RNA-seq and immunostaining and a role for SPDEF was investigated. RESULTS: SPEM markers were identified in human IPMN. GNASR201C drove expression of these markers in murine cell lines and siRNA targeting of GNASR201C or KrasG12D demonstrates that GNASR201C amplifies a mucinous phenotype. Regulon analysis identified a role for transcription factors SPDEF, CREB3L1, and CREB3L4, which are expressed in patient samples. CONCLUSIONS: De novo expression of a pyloric-type/SPEM phenotype has been identified in pancreatitis, oncogenic KrasG12D-driven pancreatic neoplasia, and in KrasG12D;GNASR201C-driven IPMN, suggesting common mechanisms of reprogramming between these lesions and the stomach. IPMN-specific GNASR201C drives a SPEM phenotype characterized by the formation of mucus producing cells at the expense of other lineages. AMR was supported by NIH T32GM139400. AM is supported by the MD Anderson Pancreatic Cancer Moon Shot Program, the Sheikh Khalifa Bin Zayed Al-Nahyan Foundation and NIH (U01CA200468, U54CA274371, U24CA274274, R01CA220236). M.C.B.T is supported by a Vanderbilt Digestive Disease Research Center Pilot and Feasibility Grant (P30 DK058404) and a Nikki Mitchell Foundation Pancreas Club Seed Grant. M.C.B.T and N.J. are supported by The Department of Defense (DOD W81XWH2211121-1). The DelGiorno laboratory is supported by the Vanderbilt Ingram Cancer Center Support Grant (NIH/NCI P30 CA068485), the Vanderbilt-Ingram Cancer Center SPORE in Gastrointestinal Cancer (NIH/NCI 5P50 CA236733), the Vanderbilt Digestive Disease Research Center (NIH/NIDDK P30 DK058404), an American Gastroenterological Association Research Scholar Award (AGA2021-13-02), NIH/NIGMS R35 GM142709, The Department of Defense (DOD W81XWH2211121), The Sky Foundation, Inc (AWD00000079), and Linda’s Hope (Nashville, TN). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

A rare case of neuroendocrine cell tumor mixed with a mucinous component in the ampulla of Vater

BackgroundA rare case of neuroendocrine cell tumor (NET) having both conventional and mucinous components was reported. Mucinous NET is rarely encountered in the pathological diagnosis of gastrointestinal (GI) tumors. Here we examined the mechanism for transformation of conventional NETs into mucinous NETs. Case presentation: Macroscopic examination revealed a tumor with ulceration in the ampulla of Vater that measured 1.7 cm in its largest diameter. Histologically, the tumor comprised two components: a tubular/ribbon-like feature and small nests floating in a mucinous lake. The tumor nests showed sheet, nest and ribbon-like structures of small cells having eosinophilic cytoplasm as well as small-sized nuclei with dense hyperchromatin. Immunohistochemical analysis showed tumor cells positive for pan-endocrine markers (synaptophysin, CD56, INSM1 and chromogranin). Based on the histological findings, the solid and mucinous components were diagnosed as conventional and mucinous NETs, respectively. Grading was NET G2 based on 12.8% and 13.2% Ki-67-positive cells in the solid and mucinous components, respectively. Immunohistochemically, the mucin phenotype of this tumor was gastric and intestinal. Only the mucinous NET component had cytoplasmic CD10 expression. Examination using a customized gene panel detected only a DPC4 mutation, which was limited to the mucinous component. Conclusions: Coexistence of conventional and mucinous NETs could provide important insight into evaluating the NET subtype histogenesis. Moreover, molecular alterations including cytoplasmic expression of CD10 and the DPC4 mutation can contribute to interpretation of tumor pathogenesis.

Genomic and Pathologic Profiling of Very Well-Differentiated Gastric Adenocarcinoma of Intestinal Type: A Study With Emphasis on Diffuse-Type Transformation.

Very well-differentiated adenocarcinoma of intestinal type is a distinct subtype of gastric cancer characterized by anastomosing glands with a hand-in-hand pattern and low-grade cytologic atypia resembling intestinal metaplasia. This is a slow-growing neoplasm with an indolent clinical course; however, a subset demonstrates transformation into adenocarcinoma with higher-grade histology, typically diffuse-type carcinoma, and behaves aggressively. This study aimed to better characterize the genomic and pathologic features, with a focus on factors associated with diffuse-type transformation. A total of 58 cases with (n=31) and without (n=27) diffuse-type transformation were analyzed for molecular and pathologic features. First, comprehensive deep DNA sequencing was conducted in 18 cases (discovery cohort), followed by a digital droplet polymerase chain reaction of hot spot RHOA mutations in 40 cases (validation cohort). In total, RHOA mutations were the most common alteration (34%), followed by loss of ARID1A (12%), p53 alterations (10%), and CLDN18 :: ARHGAP26/6 fusions (3.4%). FGFR2 amplification was identified in an advanced case with a p53 alteration. Altered p53 expression was recognized only in higher-grade components and was significantly associated with advanced disease ( P =0.0015) and diffuse-type transformation ( P =0.026). A mixed mucin phenotype was also strongly correlated with advanced disease ( P <0.001) and diffuse-type transformation ( P <0.001). Decreased E-cadherin expression was frequently observed (74%) in poorly cohesive components. This study demonstrated that a subset of RHOA -mutant diffuse-type gastric cancers develops through the transformation of very well-differentiated adenocarcinoma of intestinal type. Our observations suggest a mixed mucin phenotype as a risk factor and alterations in p53 and E-cadherin as drivers of diffuse-type transformation.

Abstract 1756: Characterizing the mutational spectrum of metastatic mucinous adenocarcinoma of the appendix

Abstract Background: Appendiceal cancer (AC) is an orphan malignancy with only 1-2 cases per 100,000 people in the US. The genomic composition of metastatic, mucinous AC is yet to be resolved at the whole exome level and few groups have assessed the clinical actionability of target genes. Here we performed whole-exome sequencing (WES) on AC specimens to 1) elucidate the mutational spectrum of AC, 2) identify recurrent mutations at frequencies unique to AC or in common with colorectal cancer (CRC), and 3) uncover recurrent AC mutations that are associated with patient survival outcomes. Methodology: Twenty-four FFPE samples, one from each of 24 AC patients treated at our institution with cytoreductive surgery (CRS) followed by heated intraperitoneal chemotherapy (HIPEC), were collected from our tumor bank with IRB approval. DNA from tumor and corresponding normal tissue (PBMCs) was extracted, assessed for integrity and quantity, then analyzed by WES using the Illumina NextSeq 6000 platform. The resulting data were processed using both GATK and DRAGEN pipelines. The frequencies of recurrent mutations in AC were compared with those of CRC from cBioPortal and statistically compared by Fisher’s Exact Test. Logrank test was performed to estimate survival associations based off mutation status. Mutational signatures derived from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium were cross-compared to our cohort to identify previously unknown mutational processes in AC. Results: The most frequent mutations were found in MUC6 (63%), KRAS (58%), HLA-B (54%), PABPC1 (50%), and MUC5AC (50%). Distinct from a 534-patient CRC cohort, AC had lower rates of alteration in APC (4% vs 73% CRC, p&amp;lt;0.001) and TP53 (21% vs. 62%, p&amp;lt;0.001), with higher rates of alteration in HLA-B (54% vs 3%, p&amp;lt;0.001), GNAS (38% vs 5%, p&amp;lt;0.001), and ABCA1 (29% vs 7%, p=0.001). Notably, ABCA1 mutation frequency was higher in mucinous CRC (n=56) when compared to non-mucinous CRC (n=478, 20% vs 7%; p&amp;lt;0.001), suggesting that ABCA1 may be uniquely altered in bowel cancers of mucinous phenotype. Alterations in Rho-A were a statistically significant predictor of poor survival in both AC (p&amp;lt;0.001) and CRC (p=0.05). PCAWG analysis showed that the predominant mutational signature in AC most resembles SBS5, suggesting that the mutational etiology of AC may be linked to age and/or smoking status. Discussion: Here we present the largest whole-exome sequencing analysis of AC analyzed to date and identify previously undescribed recurrently mutated genes unique to AC as compared to CRC. We demonstrate novel associations between altered genes and patient survival, which opens discussion regarding the clinical utility of molecular markers in AC for assisting treatment decision making. Citation Format: Daniel J. Gironda, Ming Leung, Guangxu Jin, Liang Liu, Konstantinos I. Votanopoulos, Edward A. Levine, Lance D. Miller. Characterizing the mutational spectrum of metastatic mucinous adenocarcinoma of the appendix [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1756.

Mucin phenotype and genetic alterations in non-V600E BRAF-mutated colorectal cancer

Colorectal cancer (CRC) is a heterogeneous disease that develops through stepwise accumulation of genetic alterations and progresses via several distinct pathways. However, the tumorigenesis of CRCs with BRAF non-V600E mutations remains unclear. Here, we aimed to elucidate the tumorigenesis of CRCs with BRAF non-V600E mutations, focusing on differences in mucin phenotype and genetic alterations between CRCs with non-V600E and V600E mutations. We investigated 201 patients with CRC and performed panel testing of 415 genes to identify BRAF mutations. Patients were classified into five mucin phenotypes – large-intestinal, small-intestinal, gastric, mixed, and unclassified – using immunohistochemistry for CD10, MUC2, MUC5AC, and MUC6. BRAF mutations were identified in 24 of 201 patients’ samples, of which 13 (6.5%) had a V600E mutation (V600E-mutant) and 11 (5.5%) had non-V600E mutations (non-V600E-mutant). MUC5AC expression was significantly associated with V600E mutations (P = 0.040), while CD10 expression was significantly associated with non-V600E mutations (P = 0.010). The small-intestinal mucin phenotype was significantly associated with non-V600E mutations (P = 0.031), while the mixed mucin phenotype was significantly associated with V600E mutations (P = 0.027). Regarding genetic alterations, focusing on the WNT signaling pathway, APC mutation was significantly associated with non-V600E mutations (P < 0.001), while RNF43 mutation was significantly associated with V600E mutations (P = 0.020). Considering the differences in mucin phenotype and genetic alterations, different modes of tumorigenesis are assumed for CRC with BRAF V600E mutation and non-V600E mutations. These findings are important in understanding the biology and treatment strategies for BRAF-mutant CRC.

NNMT enriches for AQP5+ cancer stem cells to drive malignant progression in early gastric cardia adenocarcinoma

ObjectiveEarly gastric cardia adenocarcinoma (EGCA) is a highly heterogeneous cancer, and the understanding of its classification and malignant progression is limited. This study explored the cellular and molecular heterogeneity in...

Relationship Between Immunophenotypes, Genetic Profiles, and Clinicopathologic Characteristics in Small Bowel Adenocarcinoma.

Small bowel adenocarcinoma (SBA) is rare, and scant data exist regarding its molecular and clinicopathologic characteristics. This study aimed to clarify the correlation between immunophenotypes, DNA mismatch repair status, genomic profiling, and clinicopathologic characteristics in patients with SBA. We examined 68 surgical resections from patients with primary SBA for immunohistochemical analyses of CK7, CK20, CD10, CDX2, MUC1, MUC2, MUC4, MUC5AC, and MUC6 expression as well as mismatch repair status. Genomic profiling was performed on 30 cases using targeted next-generation sequencing. Tumor mucin phenotypes were classified as gastric, intestinal, gastrointestinal, or null based on MUC2, MUC5AC, MUC6, and CD10 immunostaining. The expression of these proteins was categorized into 3 classifications according to their relationship to: (1) tumor location: CK7/CK20, MUC4, and MUC6; (2) histologic type: mucinous adenocarcinoma was positive for MUC2 and negative for MUC6; and (3) TNM stage: CD10 was downregulated, whereas MUC1 was upregulated in advanced TNM stages. CDX2 was a specific marker for SBA generally expressed in the small intestine. MUC1 and MUC4 expression was significantly associated with worse prognosis. MUC2 expression correlated with better prognosis, except for mucinous adenocarcinoma. Although the difference was not statistically significant, gastric-type tumors were more frequently located in the duodenum and were absent in the ileum. APC and CTNNB1 mutations were not found in the gastric-type tumors. The SBA immunophenotype correlated with tumor location, biological behavior, and genomic alterations. Our results suggest that the molecular pathway involved in carcinogenesis of gastric-type SBA differs from that of intestinal-type SBA.

Kinesin Family Member B18 Is Related to Gastric Mucin Phenotype and Contributes to Gastric Cancer Progression by Regulating Epithelial-Mesenchymal Transition

Introduction: Gastric cancer (GC) remains a common health concern worldwide and is the third leading cause of death in Japan. It can be broadly classified into gastric and intestinal mucin phenotypes using immunohistochemistry. We previously reported numerous associations of kinesin family member (KIF) genes and mucin phenotypes with GC. However, no previous studies have reported on the importance of KIF18B in GC using immunostaining. Thus, in this study, we investigated the expression and functions of KIF18B, which is highly expressed in gastric mucin phenotype GC. Methods: We performed RNA-seq of gastric and intestinal mucin type GCs, and clinicopathological studies of the KIF18B we found were performed using 96 GC cases. We also performed functional analysis using GC-derived cell lines. Result: RNA-seq showed the upregulation of matrisome-associated genes in gastric mucin phenotype GC and a high expression of KIF18B. KIF18B was detected in 52 of the 96 GC cases (54%) through immunohistochemistry. Low KIF18B expression was significantly associated with poor overall survival (p < 0.01). Other molecules that were significantly associated with KIF18B were MUC5AC and claudin 18; these were also significantly associated with the gastric mucin phenotype. KIF18B small interfering RNA (siRNA)-transfected GC cells showed greater growth and spheroid colony formation than the negative control siRNA-transfected cells. Furthermore, expression of snail family transcriptional repressor 1 and cadherin 2 was significantly increased and that of cadherin 1 was significantly decreased in KIF18B siRNA-transfected GC cells. Conclusion: These findings not only suggest that KIF18B may be a useful prognostic marker, but also provide insight into the pathogenesis of the GC phenotype.

Mucin-Phenotype and Expression of the Protein V-Set and Immunoglobulin Domain Containing 1 (VSIG1): New Insights into Gastric Carcinogenesis.

In gastric cancer (GC), intestinal metaplasia (IM) is a common precursor lesion, but its relationship to the MUC2/MUC5AC/CDX2 axis is not completely understood. Although V-set and immunoglobulin domain containing 1 (VSIG1) is supposed to be a specific marker for gastric mucosa and GC, respectively, no data about its relationship with IM or mucin phenotype have been published. The aim of our study was to explore the possible linkage between IM and these four molecules. The clinicopathological features of 60 randomly selected GCs were examined in association with VSIG1, MUC2, MUC5AC and CDX2. Two online database platforms were also used to establish the transcription factors (TFs) network involved in MUC2/MUC5AC/CDX2 cascade. IM was more frequently encountered in females (11/16 cases) and in patients below 60 years old (10/16 cases). Poorly differentiated (G3) carcinomas tended to show a loss of CDX2 (27/33 cases) but not of MUC2 and MUC5AC. MUC5AC and CDX2 were lost in parallel with the depth of invasion of the pT4 stage (28/35 and 29/35 cases), while an advanced Dukes-MAC-like stage was only correlated with CDX2 and VSIG1 loss (20/37 and 30/37 cases). VSIG1 was directly correlated with MUC5AC (p = 0.04) as an indicator of gastric phenotype. MUC2-negative cases showed a propensity towards lymphatic invasion (37/40 cases) and distant metastases, while CDX2-negative cases tended to associate with hematogenous dissemination (30/40 cases). Regarding the molecular network, only 3 of the 19 TFs involved in this carcinogenic cascade (SP1, RELA, NFKB1) interacted with all targeted genes. In GC, VSIG1 can be considered an indicator of gastric phenotype carcinomas, where carcinogenesis is mainly driven by MUC5AC. Although infrequently encountered in GC, CDX2 positivity might indicate a locally advanced stage and risk for vascular invasion, especially in tumors developed against the background of IM. The loss of VSIG1 indicates a risk for lymph node metastases.

Mucin-microbiome signatures shape the tumor microenvironment in gastric cancer

Background and aimsWe aimed to identify mucin-microbiome signatures shaping the tumor microenvironment in gastric adenocarcinomas and clinical outcomes.MethodsWe performed high-throughput profiling of the mucin phenotypes present in 108 gastric adenocarcinomas and 20 functional dyspepsia cases using validated mucin-based RT-qPCRs with subsequent immunohistochemistry validation and correlated the data with clinical outcome parameters. The gastric microbiota was assessed by 16S rRNA gene sequencing, taxonomy, and community composition determined, microbial networks analyzed, and the metagenome inferred in association with mucin phenotypes and expression.ResultsGastric adenocarcinomas with an intestinal mucin environment or high-level MUC13 expression are associated with poor survival. On the contrary, gastric MUC5AC or MUC6 abundance was associated with a more favorable outcome. The oral taxa Neisseria, Prevotella, and Veillonella had centralities in tumors with intestinal and mixed phenotypes and were associated with MUC13 overexpression, highlighting their role as potential drivers in MUC13 signaling in GC. Furthermore, dense bacterial networks were observed in intestinal and mixed mucin phenotype tumors whereas the lowest community complexity was shown in null mucin phenotype tumors due to higher Helicobacter abundance resulting in a more decreased diversity. Enrichment of oral or intestinal microbes was mucin phenotype dependent. More specifically, intestinal mucin phenotype tumors favored the establishment of pro-inflammatory oral taxa forming strong co-occurrence networks.ConclusionsOur results emphasize key roles for mucins in gastric cancer prognosis and shaping microbial networks in the tumor microenvironment. Specifically, the enriched oral taxa associated with aberrant MUC13 expression can be potential biomarkers in predicting disease outcomes.1rhtBaudS52tVmHFZhoS5HVideo

Comparison of clinical and pathological features between early-stage gastric-type and intestinal-type differentiated adenocarcinoma: a retrospective study

BackgroundThe clinicopathological features and endoscopic characteristics under magnifying endoscopy with narrow band imaging (ME-NBI) between early-stage gastric-type differentiated adenocarcinoma (GDA) and intestinal-type differentiated adenocarcinoma (IDA) remain controversial.MethodsEarly gastric adenocarcinomas that underwent endoscopic submucosal dissection (ESD) in Nanjing Drum Tower Hospital between August 2017 and August 2021 were included in the present study. GDA cases and IDA cases were selected based on morphology and immunohistochemistry staining of CD10, MUC2, MUC5AC, and MUC6. Clinicopathological data and endoscopic findings in ME-NBI were compared between GDAs and IDAs.ResultsThe mucin phenotypes of 657 gastric cancers were gastric (n = 307), intestinal (n = 109), mixed (n = 181) and unclassified (n = 60). No significant difference was observed in terms of gender, age, tumor size, gross type, tumor location, background mucosa, lymphatic invasion, and vascular invasion between patients with GDA and IDA. GDA cases were associated with deeper invasion than IDA cases (p = 0.007). In ME-NBI, GDAs were more likely to exhibit an intralobular loop patten, whereas IDAs were more likely to exhibit a fine network pattern. In addition, the proportion of none-curative resection in GDAs was significantly higher than that in IDAs (p = 0.007).ConclusionThe mucin phenotype of differentiated early gastric adenocarcinoma has clinical significance. GDA was associated with less endoscopically resectability than IDA.

Current status and perspectives for endoscopic diagnosis of superficial nonampullary duodenal epithelial tumors.

In recent years, there have been significant advances in the endoscopic resection (ER) procedures of superficial nonampullary duodenal epithelial tumors (SNADETs). A preoperative endoscopic diagnosis is thus deemed necessary in determining the indication for subsequent ER. For the histologic and endoscopic diagnosis of SNADETs, understanding the mucin phenotype is inevitable. Recently, two diagnostic algorithms for the differential diagnosis of SNADETs from nonneoplastic lesions under magnifying endoscopy with narrow-band imaging have been proposed. In addition, various endoscopic approaches have been proposed to differentiate low- and high-grade adenomas/carcinomas, including white light endoscopy, magnifying image-enhanced endoscopy, and endocytoscopy. These methods, however, have not been standardized with respect to the classification of their findings and the validation of their diagnostic accuracy. Moreover, there are still concerns with respect to the histologic criteria required to establish a SNADETs diagnosis. Standardization in the histologic and endoscopic diagnosis of SNADETs is needed.

Antitumor activity of intraperitoneal (IP) paclitaxel to mucinous appendiceal adenocarcinoma in orthotopic patient-derived xenograft model.

151 Background: Appendiceal adenocarcinomas (AAs) are a rare and heterogeneous mix of tumors for which only few preclinical models exist for drug discovery. These tumors are commonly treated with chemotherapy like those for colorectal cancer despite clear evidence that the two cancers are distinctly different in their clinical behavior and molecular profiles. Taxanes such as paclitaxel (PTX) and docetaxel have been used in the systemic treatment of gastric cancer with peritoneal metastases. IP administration of PTX has been considered a promising treatment for eliminating peritoneal metastasis, as IP delivery of PTX can attain a higher drug exposure in the peritoneal cavity with reduced systemic toxicity because of high local concentrations over a long period of time due to its hydrophobic property. The purpose of this study was to test the efficacy of IP PTX treatment in orthotopic AA PDX models. Methods: AA tumors TM00351, PMP-2 and PMCA-3 were implanted in the peritoneal cavity of NSG mice. PDX models were treated with PTX (6.25, 12.5 or 25.0 mg/kg, IP) with weekly (3 weekly treatments and 1 week off, for two cycles) or biweekly (biweekly treatments for up to 12 weeks) schedule. The peritoneal tumor burden was monitored by MRI. Solid tumor size was evaluated by modified peritoneal Response Evaluation Criteria In Solid Tumors (mpRECIST) method using ImageJ software and mucinous tumor volume was quantified by OsiriX Lite software. Results: TM00351, taken from a high-grade tumor (Grade 3), formed mucin-rich solid tumors with mucinous ascites. PDX models PMP-2 (Grade 2) and PMCA-3 (Grade 3), both with GNASR201C mutation, had a mucinous phenotype similar to GNAS mutant appendiceal tumors in humans. Weekly 25.0 mg/kg of IP PTX treatment reduced AA tumor growth of TM00351 (77.9% reduction vs. control), PMP-2 (98.6% reduction vs. control), and PMCA-3 (85.6% reduction vs. control). Similarly, biweekly 25.0 mg/kg of IP PTX treatment was effective on PMCA-3 (66.2% reduction vs. control). Survival of PMCA-3 PDX mice was significantly improved by 12.5 mg/kg (p=0.0254, log-rank test) and 25.0 mg/kg (p=0.0038) of IP PTX. At 25.0 mg/kg IP PTX treatment induced 12.0% body weight loss of PMCA-3 PDX mice 1 week after the treatment. Lower doses of IP PTX treatment, 6.25 and 12.5 mg/kg, did not induce significant body weight loss or any noticeable adverse effects on mice. Comparing the efficacy of IV to IP administration, neither 6.25 or 12.5 mg/kg of IV PTX reduced growth of PMCA-3, 25.0 mg/kg of IV PTX was lethal to mice shortly after administration. Conclusions: IP PTX is a therapeutically active for mucinous AA tumors.

Single-cell profiling reveals differences between human classical adenocarcinoma and mucinous adenocarcinoma

Colorectal cancer is a highly heterogeneous disease. Most colorectal cancers are classical adenocarcinoma, and mucinous adenocarcinoma is a unique histological subtype that is known to respond poorly to chemoradiotherapy. The difference in prognosis between mucinous adenocarcinoma and classical adenocarcinoma is controversial. Here, to gain insight into the differences between classical adenocarcinoma and mucinous adenocarcinoma, we analyse 7 surgical tumour samples from 4 classical adenocarcinoma and 3 mucinous adenocarcinoma patients by single-cell RNA sequencing. Our results indicate that mucinous adenocarcinoma cancer cells have goblet cell-like properties, and express high levels of goblet cell markers (REG4, SPINK4, FCGBP and MUC2) compared to classical adenocarcinoma cancer cells. TFF3 is essential for the transcriptional regulation of these molecules, and may cooperate with RPS4X to eventually lead to the mucinous adenocarcinoma mucus phenotype. The observed molecular characteristics may be critical in the specific biological behavior of mucinous adenocarcinoma.