Adenomatous Polyposis Coli Research Articles

POLIPOSE ADENOMATOSA FAMILIAR: UMA ABORDAGEM ABRANGENTE SOBRE A MANIFESTAÇÃO CLÍNICA, RASTREAMENTO, ABORDAGEM CIRÚRGICA E QUIMIOPREVENÇÃO

Familial Adenomatous Polyposis (FAP) is an autosomal dominant hereditary disease caused by pathogenic variants in the Adenomatous Polyposis Coli (APC) gene. The clinical picture manifests with 100 or more adenomatous colorectal polyps and is 100% associated with the risk of developing colorectal cancer (CRC). Patients with this pathology also have an increased risk of extra-colonic manifestations, such as desmoid tumors, osteomas, duodenal adenomas, including gastric cancer, and thyroid cancer. The treatment to prevent RCC is prophylactic colectomy, which has many complications and interferes with the patient's quality of life. This disease can take two forms: the classic form and the attenuated form. The classic form is represented by the presence of hundreds to thousands of adenomatous polyps in the colon and rectum, which appear in adolescence at small sizes and progressively increase in size. On the other hand, the attenuated form of familial adenomatous polyposis (FAP) manifests itself with few adenomas in the colon, starting later in life and presenting an 80% risk of malignant transformation, as well as an increased risk of extra-colonic manifestations. For this reason, the aim of this work is to discuss FAP so that it is possible to disseminate its knowledge and conduct according to the latest literature. For this reason, the aim of this work is to discuss FAP so that it is possible to disseminate its knowledge and conduct in accordance with the latest literature. An integrative literature review was therefore carried out, using a quantitative, qualitative and descriptive approach and searching the PubMed, Scielo and BVSdatabases with the descriptors: “familial adenomatous polyposis”, “Chemoprevention”, “treatment”. As a result, she was able to understand the basic concept of the disease and how it should be treated and managed on a daily basis.

The eIF3a translational control axis in the Wnt/β-catenin signaling pathway and colon tumorigenesis

Translational initiation in protein synthesis is an important regulatory step in gene expression and its dysregulation may result in diseases such as cancer. Translational control by eIF4E/4E-BP has been well studied and contributes to mTOR signaling in various biological processes. Here, we report a novel translational control axis in the Wnt/β-catenin signaling pathway in colon tumorigenesis by eIF3a, a Yin-Yang factor in tumorigenesis and prognosis. We show that eIF3a expression is upregulated in human colon cancer tissues, pre-cancerous adenoma polyps, and associates with β-catenin level and APC mutation in human samples, and that eIF3a overexpression transforms intestinal epithelial cells. We also show that eIF3a expression is regulated by the Wnt/β-catenin signaling pathway with an active TCF/LEF binding site in its promoter and that eIF3a knockdown inhibits APC mutation-induced spontaneous colon tumorigenesis in APCmin/+ mice. Together, we conclude that eIF3a upregulation in colon cancer is due to APC mutation and it participates in colon tumorigenesis by adding a translational control axis in Wnt/β-catenin signaling pathway and that it can serve as a potential target for colon cancer intervention.

Homologous recombination deficiency score is an independent prognostic factor in esophageal squamous cell carcinoma.

Homologous recombination deficiency (HRD) represents an impairment in the homologous recombination repair (HRR) pathway, crucial for repairing DNA double-strand breaks and contributing to genomic instability in cancer. The HRD score may be a more reliable biomarker than HRR-related gene mutations for identifying patients sensitive to poly(ADP-ribose) polymerase inhibitors. Despite its relevance in various cancers, the HRD score remains underexplored in esophageal squamous cell carcinoma (ESCC). We retrospectively analyzed HRD scores in 96 ESCC patients, examining correlations with clinical characteristics and survival outcomes, and validated our findings using the TCGA dataset. Genomic sequencing utilized a custom superHRD next-generation sequencing panel, and HRD scores were calculated from 54,000 single-nucleotide polymorphisms using Kruskal-Wallis rank-sum tests and two cut-off points for analysis. Higher HRD scores correlated with advanced tumor stages, recurrence, and mutations in TP53 and ABCB1, while APC mutations were linked to lower HRD scores. Patients with high HRD scores had significantly shorter disease-free survival (p = 0.013) and a trend toward shorter overall survival (OS) (p = 0.005), particularly those not receiving adjuvant therapy. Conversely, HRD-high patients undergoing adjuvant therapy showed a trend toward longer OS (p = 0.015). Multivariate analysis identified HRD as an independent prognostic factor (hazard ratio = 2.814 for recurrence, p = 0.015). Validation with the TCGA dataset supported these findings. This study highlights the associations between HRD scores, clinical characteristics, and genomic mutations in ESCC, suggesting HRD as a potential prognostic biomarker. HRD assessment may aid in patient stratification and personalized treatment strategies, warranting further investigation to validate the therapeutic implications of HRD scores in ESCC.

Cancer Risks in Attenuated and Classical Familial Adenomatous Polyposis: A Nationwide Cohort with Matched, Non-Exposed Individuals: Cancer and surgery in AFAP and FAP patients.

Familial adenomatous polyposis (FAP) is caused by pathogenic variants in the APC gene. FAP is usually categorized according to phenotype: classical FAP (CFAP) and attenuated FAP (AFAP); the latter is considered to have a milder disease course. We aimed to assess the risk of overall and specific cancers in CFAP and AFAP patients compared to matched, non-exposed individuals. All known Danish FAP patients were classified as either CFAP or AFAP and assigned four matched, non-exposed individuals. The risk of overall and specific cancers, and mortality were analyzed. The analysis included 311 CFAP patients, 134 AFAP patients, and 1,600 non-exposed individuals. The overall cancer risk was significantly higher for both CFAP and AFAP patients than for non-exposed individuals, with hazard ratios (HR) of 4.77 (95% confidence interval (CI), 3.61-6.32; P<0.001) for CFAP and 3.22 (95% CI, 2.16-4.80; P<0.001) for AFAP. No significant difference was observed when comparing CFAP and AFAP (HR=1.48; 95% CI, 0.98-2.25; P=0.0646). The HR of colonic cancer was 2.16 (95% CI, 0.99-7.72; P=0.0522) and 2.72 (95% CI, 1.19-6.22; P=0.0177 for CFAP and AFAP), respectively compared to non-exposed and did not differ between CFAP and AFAP patients (HR=0.80; 95% CI, 0.32-2.00; P=0.6278). Mortality was significantly higher in CFAP (HR=2.96; 95% CI, 2.04-4.28; P<0.001), but not in AFAP (HR=1.40; 95% CI, 0.73-2.69; P=0.311). Nationwide data reveal differing risk profiles for specific cancers and mortality in AFAP and CFAP compared to non-exposed individuals. The cancer burden of AFAP necessitates consistent monitoring of these patients.

Polyclonality overcomes fitness barriers in Apc-driven tumorigenesis.

Loss-of-function mutations in the tumour suppressor APC are an initial step in intestinal tumorigenesis1,2. APC-mutant intestinal stem cells outcompete their wild-type neighbours through the secretion of Wnt antagonists, which accelerates the fixation and subsequent rapid clonal expansion of mutants3-5. Reports of polyclonal intestinal tumours in human patients and mouse models appear at odds with this process6,7. Here we combine multicolour lineage tracing with chemical mutagenesis in mice to show that a large proportion of intestinal tumours have a multiancestral origin. Polyclonal tumours retain a structure comprising subclones with distinct Apc mutations and transcriptional states, driven predominantly by differences in KRAS and MYC signalling. These pathway-level changes are accompanied by profound differences in cancer stem cell phenotypes. Of note, these findings are confirmed by introducing an oncogenic Kras mutation that results in predominantly monoclonal tumour formation. Further, polyclonal tumours have accelerated growth dynamics, suggesting a link between polyclonality and tumour progression. Together, these findings demonstrate the role of interclonal interactions in promoting tumorigenesis through non-cell autonomous pathways that are dependent on the differential activation of oncogenic pathways between clones.

Cutaneous Metastasis of Rectal Cancer as a Diagnostic Challenge: A Clinical Case and Literature Review

Background/Objectives: Metastatic colorectal cancer remains a fatal disease, with a 5-year survival rate lower than 15%. The most common metastatic sites are the lungs and the liver, while skin metastases are very rare and often indicate a poor prognosis with a lower survival rate. Methods. Herein, we present the clinical case of a 62-year-old female patient with rectal cancer metastases to the skin of the anogenital and abdominal regions, diagnosed 2 years after completion of treatment of the underlying disease. Results: Histological examination of the skin lesions revealed adenocarcinoma, and expression of the same immunohistochemical markers was also found in the primary tumor and in the cutaneous metastases. However, next-generation sequencing demonstrated differences in the mutational profiles of the primary tumor and metastasis to the skin. Somatic mutations in the APC, TP53, and PTPN11 genes were revealed in primary rectal adenocarcinoma, but another pathogenic TP53 mutation and a frameshift variant in the DYNC1I1 gene were found in cutaneous metastases. The patient underwent several courses of FOLFOX6 chemotherapy in combination with bevacizumab, but the treatment was unsuccessful. An analysis of 50 clinical cases from the literature concerning various manifestations of cutaneous metastases of rectal cancer showed a median survival of 8.5 months from the time of detection of the skin lesions. Conclusions: In this regard, careful skin examination of patients with rectal cancer and timely detection of cutaneous metastases are essential steps in the follow-up of patients who have undergone treatment of the primary tumor.

Expression of Concern: Apc gene suppresses intracranial aneurysm formation and rupture through inhibiting the NF-κB signaling pathway mediated inflammatory response.

Expression of Concern: Apc gene suppresses intracranial aneurysm formation and rupture through inhibiting the NF-κB signaling pathway mediated inflammatory response.

Polyclonal-to-monoclonal transition in colorectal precancerous evolution.

Unravelling the origin and evolution of precancerous lesions is crucial for effectively preventing malignant transformation, yet our current knowledge remains limited1-3. Here we used a base editor-enabled DNA barcoding system4 to comprehensively map single-cell phylogenies in mouse models of intestinal tumorigenesis induced by inflammation or loss of the Apc gene. Through quantitative analysis of high-resolution phylogenies including 260,922 single cells from normal, inflamed and neoplastic intestinal tissues, we identified tens of independent celllineages undergoing parallel clonal expansions within each lesion. We also found polyclonal origins of human sporadic colorectal polyps through bulk whole-exome sequencing and single-gland whole-genome sequencing. Genomic and clinical data support a model of polyclonal-to-monoclonal transition, with monoclonal lesions representing a more advanced stage. Single-cell RNA sequencing revealed extensive intercellular interactions in early polyclonal lesions, but there was significant loss of interactions during monoclonal transition. Therefore, our data suggest that colorectal precancer is often founded by many different lineages and highlight their cooperative interactions in the earliest stages of cancer formation. These findings provide insights into opportunities for earlier intervention in colorectal cancer.

Effect of anti-inflammatory molecules from food on organoids derived from adenomatous polyps of FAP subjects.

Individuals with Familial Adenomatous Polyposis (FAP) or APC-associated polyposis, an autosomal dominant inherited condition, develop multiple adenomatous polyps and have an increased colorectal cancer (CRC) risk. A change in diet can help reduce cancer risk, and several dietary components have an antitumor effect. We aimed to evaluate the potential of the anti-inflammatory and anticancer substances quercetin (QER), epigallocatechin gallate (EGG) and fisetin (FIS) in decreasing the risk of CRC by reducing the growth of polyps in an organoid model. Patient-derived organoid (PDO) lines were generated from polyps obtained from patients with FAP undergoing prophylactic colectomy. PDOs were treated with QER, EGG, or FIS to determine their effect on cell growth. Changes in caspase 3/7 activity and expression of inflammation and apoptosis mediators were assessed by luminescent and colorimetric assays. Three PDO lines with different inactivating pathogenic variants in the APC gene were developed using a combinatorial approach. FIS was the most active of the three substances tested, presenting the lowest IC50 in all PDO lines (range: 42.6-9.2 uM). The IC50 was defined as the concentration required to halve the number of cells after 72 hours. All molecules tested induced apoptosis through activation of caspases 3/7. QER, EGG, and FIS can be easily taken from foods or dietary supplements, show toxicity on PDOs derived from adenomatous polyps, while they are known to be harmless on normal cells. Diets enriched with these substances could be potential supplemental treatments to reduce the risk of CRC in individuals with FAP.

Comparative Analysis of Commercial and Home-Made Media on RSPO1/S6R Axis in Organoids with Different Wnt Backgrounds: A Methodological Guide for the Selection of Intestinal Patient-Derived Organoids Culture Media

WNT3A is an intestinal ligand triggering the Wnt/β-catenin (Wnt) pathway, which can be enhanced by R-spondin 1 (RSPO1) through the RSPO1–LGR axis or antagonized by the adenomatous polyposis coli (APC) protein supporting β-catenin-degradation. Wnt interplays with several pathways including PI3K/mTOR (mTOR). In this study, we evaluated the influence of WNT3A-commercial and home-made culture media and RSPO1 protein on the Wnt and mTOR interplay in non-APC and APC-mutated intestinal patient-derived organoids (PDOs). Normal mucosa (NM) of sporadic CRC and FAP PDOs were cultured with: WNT3A-lacking/containing commercial (A/A+B) or home-made (BASAL/WNT3A-conditioned medium (CM)±RSPO1) media. In non-APC-mutated-PDOs (CRC-NM), WNT3A-CM, over commercial A+B, strongly activated Wnt-target-genes CCND1 and c-MYC. Most importantly, the addition of RSPO1 to home-made WNT3A-CM or A+B led to the downregulation of the mTOR-downstream-effector phospho-S6 ribosomal protein (p-S6R), highlighting the activation of the RSPO1–pS6R in both non-APC (CRC-NM) and APC-mutated (FAP-NM) PDOs, independently from LGR5 gene expression modulation. Our work demonstrates that home-made WNT3A-CM strongly impacts the crosstalk between Wnt and mTOR over commercial media, and proposes RSPO1 as a key regulator of the RSPO1–p-S6R axis in both non-APC and APC-mutated PDOs. Together, these findings represent an important methodological guide for scientists working in these fields to select the most appropriate intestinal PDO media.

Polygenic anti-cancer activity of Indigofera macrophylla in prostate cancer induced animal model

BackgroundProstate cancer (Pca) is a deadly disease prevalent among men, and it accounts for about 7–8 % of mortality globally. Synthetic drugs have proved effective but have limitations and severe side effects. There is, therefore, a need to discover a less expensive, natural therapeutic agent with no side effects in treating the ailment. AimThe study aims to investigate the anti-prostate cancer activity of extracts of Indigofera macrophylla (I. macrophylla) at the physiological and molecular levels in experimental animals. MethodPolyphenol-rich extract of I. macrophylla was subjected to HPLC analysis to identify the plant's phytochemical constituent. Adult Wistar rats were orally administered 2mls of 50, 100 and 200 PPM of the cacodylic acid solution for 28 days to induce prostate cancer, while treatment was carried out by orally administering extract of I. macrophylla at doses of 50, 100 and 200 mg/kg for up to 28 days. The anti-inflammatory and apoptotic properties of the extract in experimental animals were investigated by the expression levels of various genetic biomarkers such as Bax-2, TNF-α, IL-6, COX2, IL-1β, β-Catenin, APC, Bcl2, CEA, Caspase 3 and β-Catenin using reverse transcriptase polymerase chain reaction (RT-PCR). ResultHPLC analysis shows that I. macrophylla has 21 bioactive components which are categorized into seven groups: flavonoid, terpenes, phenols, isoflavonoid, phytosterols, quinone and glycosides. Administration of the drug shows inconsistencies in the mean body weights of the experimental animals. Further investigation revealed that I. macrophylla increased TNF-α upregulation and expression, significantly downregulated IL-1β, significantly decreased IL-6 expression, ameliorated COX2 expression, downregulated β-catenin expression and significantly reduced the expression of the APC gene. These results show that the drug activity modulates the investigated inflammatory and apoptotic genes in the prostate gland of PCa-induced rats, thus demonstrating its anti-PCa potential. ConclusionThe results of this study suggest the potential of a novel treatment protocol of I. macrophylla plant extract to improve therapeutic outcomes for patients with aggressive PCa, which reportedly claims hundreds of thousands of lives yearly.

Adenomatous Polyposis Coli (APC) Promoter Gene Methylation in Urine-Derived DNA: A Non-invasive Biomarker for Early Bladder Cancer Detection and Tumor Aggressiveness

Adenomatous Polyposis Coli (APC) Promoter Gene Methylation in Urine-Derived DNA: A Non-invasive Biomarker for Early Bladder Cancer Detection and Tumor Aggressiveness

Two-hit model for the development of aldosterone-producing adenoma: supporting from two new cases.

Recently, a two-hit model for the development of aldosterone-producing adenoma (APA) was proposed but until now, only two cases supporting the model have been reported. Here, we present two new cases of primary aldosteronism (PA), both of which had large functional adenomas with somatic mutations in aldosterone-driving genes. Furthermore, the first patient, who had a history of colorectal cancer, was found to have a germline and an additional somatic mutation in APC, and APC inactivation was confirmed by immunohistochemistry. The other patient had pathogenic somatic mutation inCTNNB1. These pro-proliferation mutations resulted in abnormal activation of the Wnt/β-catenin pathway. Two consecutive events apparent in these patients, namely, the first event leading to cell proliferation and the second driving hormonal hypersecretion, supported the two-hit model of APA development. The two-hit model usually occurs in the larger adenomas, and the driving factors of the first hit that promote cell proliferation still require further research and exploration.

The terrestrial flatworm Microplana scharffi (Geoplanidae, Microplaninae): mitochondrial genome, phylogenetic proximity to the Bipaliinae and genes related to regeneration

A genome skimming approach of sequencing was undertaken on a subfamily of terrestrial flatworms that had been neglected in genomic studies until now, namely the Microplaninae as represented here by Microplana scharffi. A single run of short-read sequencing enabled retrieval of the complete mitogenome, the two paralogous versions of the 18S gene, the elongation factor gene EF1α, plus two genes involved in the regeneration process, namely those coding for ß-CATENIN-1 and adenomatous polyposis coli (APC). The 15,297 bp mitogenome lacks a functional tRNA-Ala and has a mandatory alternative TTG start codon in its cox1 gene. The multiprotein phylogeny, inferred from mitogenome proteins, positions M. scharffi as sister-group to the Bipaliinae with maximum support, although the organisation of the mitogenomes shows features previously never observed among Bipaliinae, such as the conserved 32 bp overlap between ND4 and ND4L. Similarly to what has been observed in recent publications on other species of Geoplanidae, the two types of 18S genes display strongly different coverages and are only 90.57% identical. Additionally, alien DNA was identified in the pool of contigs in the form of the complete mitochondrial genome of Lumbricus rubellus, confirming previous observations on the feeding habits of M. scharffi.

Innovative Oral Nano/Gene Delivery System Based on Engineered Modified Saccharomyces cerevisiae for Colorectal Cancer Therapy.

The efficient delivery of RNA-based drugs to solid tumors remains a formidable obstacle. We aim to develop a safe and efficient oral drug delivery system compatible with RNA-based drugs that is urgently needed to overcome challenges such as enzymatic degradation and gastrointestinal barriers to facilitate effective treatment for treating colorectal cancer (CRC). To address these challenges, we utilized engineered modified Saccharomyces cerevisiae to evaluate the delivery efficacy of miR21-antagomir for treating CRC in preclinical mouse models, including adenomatosis polyposis coli mutant transgenic mice ApcMin/+ and in situ tumor-bearing mice. An orally deliverable gene delivery system, YS@NPs21, was designed. This gene delivery system demonstrated effectively suppressed tumor growth in both ApcMin/+ and in situ tumor-bearing mice models. This system exhibited tumor-targeting capability, effective inhibition of tumor growth, and low toxicity toward nontumor cells. Successful implementation of this innovative oral drug delivery system could offer a straightforward, safe, and RNA drug-compatible approach to CRC treatment, ultimately improving patient outcomes and reducing medical costs.

Familial adenomatous polyposis gene MUTYH mutations are identified in anaplastic thyroid carcinoma

Abstract Introduction/Objective Anaplastic thyroid carcinoma (ATC) is a rare aggressive disease unresponsive to treatment. Next-Generation Sequencing (NGS) allows identification of targets for precision therapies, such as BRAF, with implications in treating ATC. Our prior work identified ATC clusters with characteristic gene mutations and multiple previously unreported mutations. One of these is MUTYH, which is associated with colon (CRC), ovarian, breast, bladder, and duodenal carcinomas in MUTYH-associated polyposis (MAP). Its association with ATC is not defined. Methods/Case Report Exploratory analysis of pathogenic mutations in 727 ATC cases using a 324-gene panel (FoundationOneCDx) and an interactive visualization of association rules was conducted for informative maximal frequent patterns among mutated gene combinations to identify gene clusters including genes not commonly associated with ATC. TCGA database was reviewed for frequency of MUTYH mutations. My Cancer Genome and the Drug-Gene Interaction Database were used to identify potential targeted drugs for MUTYH gene-mutated cancers. Results (if a Case Study enter NA) NGS showed MUTYH short-variant mutations in 17 cases (2.34%). Germline MUTYH variants incidence is 1.43% in normal samples. 5 cases harbored only Y165C and 7 had only G382D, with 1 case having both Y165C and G382D. The other 4 cases contained sporadic truncating events in MUTYH. All instances of Y165C and G382D were predicted to be germline. 6 patients (35%) had BRAF co-mutations, correlating with expected frequency of ATC thought to transform from papillary carcinoma (PC). One case had only MUTYH mutation while a second had MUTYH with TERT and TP53. TCGA database contained 6(0.2%) cases of PC with MUTYH mutations (total 2871 MUTYH-mutated carcinomas), but no cases of ATC or other thyroid tumors were described. Conclusion MUTYH is a DNA repair enzyme linked to CRC and other cancers. MUTYH mutations occur in 6.7% of MAP patients and 1–2.2% of sporadic CRC cases that are mutually exclusive of BRAF mutations. While MAP increases the lifetime risk of CRC by over 60%, the link of MUTYH mutations to PC has only been observed in MAP and not been described outside of it. To our knowledge this is the first description of MUTYH mutations in ATC, especially without concurrent BRAF mutation (11 cases), suggesting MUTYH may independently contribute to pathogenesis of ATC. PARP inhibitors, PD-1/PD-L1 inhibitors, and ATR inhibitors demonstrate promising results in clinical trials of MUTYH-mutated cancers, warranting further research.

Características genéticas y manifestaciones fenotípicas extracolónicas en pacientes con poliposis adenomatosa familiar

IntroductionFamilial adenomatous polyposis (FAP) is a hereditary disease caused by mutations in the APC gene, which is also associated with extracolonic manifestations. The objective was to characterize the extracolonic manifestations in a cohort of patients with classic FAP and the possible genotype-phenotype association. Materials and methodsThe study design was observational and descriptive. Demographic, clinical, and genetic variables were collected based on the type of mutation (frameshift, nonsense, splicing, rearrangement, and others). ResultsWe included 45 patients with FAP (mean age 47years, range 21-78; 51% female), belonging to 21 families, with a median of 2 (range 0-6) manifestations per patient. Eighty percent (n=36) had upper digestive tract involvement, with duodenal adenomas (73%), fundic gland polyposis (56%), and ampullary adenoma (36%) being the most frequent findings. The most common extraintestinal manifestations were desmoid tumors (16%) and papillary thyroid carcinoma (13%). Thirty eight percent of the patients presented an aggressive phenotype (SpigelmanIII-IV, high-grade dysplasia, invasive neoplasia, desmoid tumor, and papillary thyroid carcinoma). The most common genetic mutations were frameshift (56%), nonsense (26%), and splicing (16%), primarily located in exon15 (50%). No significant correlation was found between the type of genetic mutation and the severity or location of phenotypic manifestations. ConclusionsOne-third of patients with FAP present an aggressive phenotype, without a demonstrated correlation between the type of genetic alteration and the phenotypic manifestations.

Adenomatous Polyposis Coli Gene Mutations, Risk Factors, and Long-term Outcomes Associated With Desmoid Tumors in Patients With Familial Adenomatous Polyposis After Colectomy in Japan

Goals: To clarify the characteristics of desmoid tumors in Japanese patients with familial adenomatous polyposis after colectomy. Background: Few comprehensive reports have been published on desmoid tumors in Asian patients with familial adenomatous polyposis. Study: This retrospective study included the data of 81 patients with familial adenomatous polyposis who underwent surgery between 1978 and 2021. The adenomatous polyposis coli gene mutation sites, risk factors, and long-term outcomes associated with desmoid tumors in Japanese patients with familial adenomatous polyposis after colectomy were analyzed. Results: No association was observed between the gene mutation sites and desmoid tumor development in 40 patients who underwent genetic analyses. The rate of desmoid tumor development was 30.3% in 66 patients. Multivariate analysis revealed that age below 32 years at colectomy (hazard ratio = 5.491, 95% confidence interval 1.820-16.50, P &lt; 0.001) and familial adenomatous polyposis-related malignancies other than colorectal cancer (hazard ratio = 5.574, 95% confidence interval 2.075-14.98, P &lt; 0.001) were independent risk factors for desmoid tumor development following colectomy. The 10-year disease-specific survival and overall survival rates for desmoid tumors were 92.9% and 76.9%, respectively. The median surveillance duration was 90 months. Conclusions: Adenomatous polyposis coli gene mutation sites alone were not considered a factor for delaying or avoiding colectomy to prevent desmoid tumors in Japanese patients with familial adenomatous polyposis. The timing of colectomy and careful surveillance should be considered for managing patients at a high risk of developing desmoid tumors. Desmoid tumors in patients with familial adenomatous polyposis did not significantly impact prognosis, and pharmacological treatments are important for disease control.

Mutational analysis differentiating sporadic carcinomas from colitis-associated colorectal carcinomas

BackgroundUlcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) that is associated with increased risk of developing colitis-associated carcinoma (CAC). The genetic profile of CACs is fairly similar to the sporadic colorectal carcinomas (sCRCs), although showing certain differences in the timing and sequence of alterations that contribute to carcinogenesis. Also, both cancer types typically show a strong histological resemblance, which complicates the pathologists’ diagnosis. Due to the different clinical consequences, it is of utmost importance to categorize the corresponding cancer type correctly.MethodsIn this study, we determined the mutation profiles of 64 CACs and sCRCs in the hotspot regions of 50 cancer-associated genes and compared them to 29 controls to identify genetic gene variants that can facilitate the pathologists’ diagnosis. Pearson Chi-Square or Fisher’s exact tests were used for statistical analyses.ResultsWe found that sCRCs tend to mutate more frequently in APC and PIK3CA genes than CACs and that mainly males were affected. Our CAC cohort identified the KRAS G12D mutation as group-specific variant that was not detected in the sCRCs. When separating conventional from non-conventional CACs, it was discovered that the conventional type shows significantly more mutations for ATM.ConclusionsTaken together, our data highlights genetic differences between sCRC and CAC and enables the possibility to utilize specific gene alterations to support the pathologist’s diagnosis.

MSH6-proficient crypt foci in MSH6 constitutional mismatch repair deficiency: reversion of a frameshifted coding microsatellite to its wild-type sequence.

The discovery of "mismatch repair deficient (MMRd)-crypt foci" in non-neoplastic intestinal mucosa in Lynch syndrome (LS) has significantly enhanced our understanding of how tumors and tumor immunity form and evolve in LS. In this study, we report the frequent presence of "mismatch repair proficient (MMRp)-crypt foci" in both non-neoplastic and neoplastic intestinal mucosa in a patient with constitutional MMR deficiency (CMMRD), who carried a germline MSH6 pathogenic variant (c.3261dupC) in trans with an MSH6 likely pathogenic variant (c.3724_3726del) and whose tissues were otherwise deficient in MMR globally. The MMRp-crypts occurred at a rate of 1.1/100 crypts in non-neoplastic intestinal mucosa and were readily discernible in adenomas > 1cm. Sequencing analysis revealed normalization of the MSH6c.3261dupC variant in MMRp-adenoma crypts, indicating reverse frameshifting of the exon 5 C8 microsatellite. Interestingly but not surprisingly, the MMRp-adenoma crypts remained microsatellite-instability-high (MSI-H), and shared oncogenic APC mutations with the background MMRd-adenoma. Contrasting with MSH6-CMMRD, no PMS2-CMMRD individuals (0/5) harbored MMRp-crypts. In conclusion, our study documents distinct MMRp-crypts in MSH6-CMMRD, a phenomenon in keeping with MSH6 being a frequent target of MSI-H due to its coding microsatellite and suggesting that MSH6-CMMRD can potentially serve as a unique model system to further our understanding of MSH6's role in MSI-H tumor formation and evolution. Our findings also bear diagnostic implications; when using MMR immunohistochemistry as an ancillary tool in detecting CMMRD, awareness of these MMRp crypts can help avoid diagnostic pitfalls.