Familial adenomatous polyposis: a case report.

BACKGROUND: Familial adenomatous polyposis is characterized by the presence of multiple colorectal adenomatous polyps and caused by germline mutations in the tumor suppressor gene and adenomatous polyposis coli, located on chromosome 5q21-q22. Familial adenomatous polyposis occurs in approximately 1/10,000 to 1/30,000 live births, and accounts for less than 1% of all colorectal cancers in the USA. It affects both sexes equally and has a worldwide distribution. The incidence of colon cancer in low- and middle-income countries is rising. In addition to the increasing incidence, lack of early detection and impeded access to optimal multidisciplinary treatment may worsen survival outcomes. Developing quality diagnostic services in the proper health context is crucial for early diagnosis and successful therapy of patients with colorectal cancer, and applying a resource-sensitive approach to prioritize essential treatments on the basis of effectiveness and cost-effectiveness is key to overcoming barriers in low- and middle-income countries. We report a case of familial adenomatous polyposis presenting as adenocarcinoma with multiple colorectal adenomatous polyps. The diagnosis of familial adenomatous polyposis was made by the presence of numerous colorectal adenomatous polyps and family history of colonic adenocarcinoma. Due to its rarity, we decided to report it. CASE PRESENTATION: A 22-year-old Ethiopian female patient presented to Addis Ababa University College of Health science, Addis Ababa, Ethiopia with rectal bleeding. Abdominopelvic computed tomography scan was done and showed distal rectal asymmetric anterior wall thickening in keeping with rectal tumor. Colonoscopy was done and she was diagnosed to have familial adenomatous polyposis with severe dysplasia. In the meantime, colonoscopy guided biopsy was taken and the diagnosis of adenocarcinoma with familial adenomatous polyposis was rendered. For this, total proctocolectomy was carried out. On laparotomy there was also incidental finding of left ovarian deposition for which left salpingo-oophorectomy was done, and 4 weeks after surgical resection, the patient was started on oxaliplatin, leucovorin, fluorouracil chemotherapy regimen. CONCLUSION: In the clinical evaluation of a patient with rectal bleeding, familial adenomatous polyposis must be considered as a differential diagnosis in subjects having family history of colonic adenocarcinoma for early diagnostic workup, management, family genetic counseling, and testing.

Differential Regulation of Wingless-Wnt/c-Jun N-Terminal Kinase Crosstalk via Oxidative Eustress in Primary and Metastatic Colorectal Cancer Cells.

In the tumor microenvironment (TME), ROS production affects survival, progression, and therapy resistance in colorectal cancer (CRC). H2O2-mediated oxidative stress can modulate Wnt/ß-catenin signaling and metabolic reprogramming of the TME. Currently, it is unclear how mild/moderate oxidative stress (eustress) modulates Wnt/ß-catenin/APC and JNK signaling relationships in primary and metastatic CRC cells. In this study, we determined the effects of the H2O2 concentration inducing eustress on isogenic SW480 and SW620 cells, also in combination with JNK inhibition. We assessed cell viability, mitochondrial respiration, glycolysis, and Wnt/ß-catenin/APC/JNK gene and protein expression. Primary CRC cells were more sensitive to H2O2 eustress combined with JNK inhibition, showing a reduction in viability compared to metastatic cells. JNK inhibition under eustress reduced both glycolytic and respiratory capacity in SW620 cells, indicating a greater capacity to adapt to TME. In primary CRC cells, H2O2 alone significantly increased APC, LEF1, LRP6, cMYC and IL8 gene expression, whereas in metastatic CRC cells, this effect occurred after JNK inhibition. In metastatic but not in primary tumor cells, eustress and inhibition of JNK reduced APC, ß-catenin, and pJNK protein. The results showed differential cross-regulation of Wnt/JNK in primary and metastatic tumor cells under environmental eustress conditions. Further studies would be useful to validate these findings and explore their therapeutic potential.

Enhanced ApcMin/+ adenoma formation after epithelial CUL4B deletion by recruitment of myeloid-derived suppressor cells.

Colorectal cancer (CRC) stands as a prevalent malignancy globally. A pivotal event in CRC pathogenesis involves the loss-of-function mutation in the APC gene, leading to the formation of benign polyps. Despite the well-established role of APC, the contribution of CUL4B to CRC initiation in the pre-tumorous stage remains poorly understood. In this investigation, we generated a murine model by crossing ApcMin/+ mice with Cul4bΔIEC mice to achieve specific deletion of Cul4b in the gut epithelium against an ApcMin/+ background. By employing histological methods, RNA-sequencing (RNA-seq), and flow cytometry, we assessed alterations and characterized the immune microenvironment. Our results unveiled that CUL4B deficiency in gut epithelium expedited ApcMin/+ adenoma formation. Notably, CUL4B in adenomas restrained the accumulation of tumor-infiltrating myeloid-derived suppressor cells (MDSCs). In vivo inhibition of MDSCs significantly delayed the growth of CUL4B deleted ApcMin/+ adenomas. Furthermore, the addition of MDSCs to in vitro cultured ApcMin/+; Cul4bΔIEC adenoma organoids mitigated their alterations. Mechanistically, CUL4B directly interacted with the promoter of Csf3, the gene encoding granulocyte-colony stimulating factor (G-CSF) by coordinating with PRC2. Inhibiting CUL4B epigenetically activated the expression of G-CSF, promoting the recruitment of MDSCs. These findings offer novel insights into the tumor suppressor-like roles of CUL4B in regulating ApcMin/+ adenomas, suggesting a potential therapeutic strategy for CRC initiation and progression in the context of activated Wnt signaling.

Surgical Decision-Making in Familial Adenomatous Polyposis.

Familial adenomatous polyposis (FAP) is an autosomal dominant disorder affecting patients with germline mutations of the adenomatous polyposis coli (APC) tumor suppressor gene. The surgical treatment of colorectal disease in FAP, which has the goal of colorectal cancer prevention, varies based on both patient and disease factors but can include the following: total colectomy with ileorectal anastomosis, proctocolectomy with stapled or hand-sewn ileal pouch-anal anastomosis, or total proctocolectomy with end ileostomy. The operative options and extent of resection, as well as the use of endoscopy and chemoprevention for the management of polyposis, will be discussed in detail in this article. In addition, commonly debated management decisions related to the treatment of patients with FAP, including the timing of prophylactic colorectal resections for patients with FAP and management of the polyp burden in the rectum, will be discussed. Finally, genotype considerations and the impact of desmoid disease on operative decisions in the setting of FAP will also be reviewed.

Ehrlichia chaffeensis TRP120 ubiquitinates tumor suppressor APC to modulate Hippo and Wnt signaling.

Ehrlichia chaffeensis: TRP120 is a multifunctional effector that acts as a ligand mimic to activate evolutionary conserved eukaryotic signaling pathways Notch, Wnt, Hedgehog and Hippo. In addition, TRP120 is also a HECT E3 ubiquitin ligase known to ubiquitinate several host cell regulatory proteins (FBW7, PCGF5 and ENO-1) for degradation. We previously determined that TRP120 ubiquitinates the Notch negative regulator, FBW7, to maintain Notch signaling and promote infection. In this study, we investigated a potential mechanism used by Ehrlichia chaffeensis to maintain Hippo and Wnt signaling by ubiquitinating the tumor suppressor, adenomatous polyposis coli (APC), a negative regulator of Wnt and Hippo signaling. We determined that APC was rapidly degraded during E. chaffeensis infection despite increased APC transcription. Moreover, RNAi knockdown of APC significantly increased E. chaffeensis infection and coincided with increased active Yap and ß-catenin in the nucleus. We observed strong nuclear colocalization between TRP120 and APC in E. chaffeensis-infected THP-1 cells and after ectopic expression of TRP120 in HeLa cells. Additionally, TRP120 interacted with both APC full length and truncated isoforms via co-immunoprecipitation. Further, TRP120 ubiquitination of APC was demonstrated in vitro and confirmed by ectopic expression of a TRP120 HECT Ub ligase catalytic site mutant. This study identifies APC as a TRP120 HECT E3 Ub ligase substrate and demonstrates that TRP120 ligase activity promotes ehrlichial infection by degrading tumor suppressor APC to positively regulate Hippo and Wnt signaling.

Microenvironmental changes in familial adenomatous polyposis during colorectal cancer carcinogenesis.

Familial adenomatous polyposis (FAP) is a heritable disease that increases the risk of colorectal cancer (CRC) development because of heterozygous mutations in APC. Little is known about the microenvironment of FAP. Here, single-cell RNA sequencing was performed on matched normal tissues, adenomas, and carcinomas from four patients with FAP. We analyzed the transcriptomes of 56,225 unsorted single cells, revealing the heterogeneity of each cell type, and compared gene expression among tissues. Then we compared the gene expression with that of sporadic CRC. Furthermore, we analyzed specimens of 26 FAP patients and 40 sporadic CRC patients by immunohistochemistry. Immunosuppressiveness of myeloid cells, fibroblasts, and regulatory T cells was upregulated even in the early stages of carcinogenesis. CD8+ T cells became exhausted only in carcinoma, although the cytotoxicity of CD8+ T cells was gradually increased according to the carcinogenic step. When compared with those in the sporadic CRC microenvironment, the composition and function of each cell type in the FAP-derived CRC microenvironment had differences. Our findings indicate that an immunosuppressive microenvironment is constructed from a precancerous stage in FAP.

Gene-specific ACMG/AMP classification criteria for germline APC variants: Recommendations from the ClinGen InSiGHT Hereditary Colorectal Cancer/Polyposis Variant Curation Expert Panel.

PURPOSE: The Hereditary Colorectal Cancer/Polyposis Variant Curation Expert Panel (VCEP) was established by the International Society for Gastrointestinal Hereditary Tumours and the Clinical Genome Resource, who set out to develop recommendations for the interpretation of germline APC variants underlying Familial Adenomatous Polyposis, the most frequent hereditary polyposis syndrome. METHODS: Through a rigorous process of database analysis, literature review, and expert elicitation, the APC VCEP derived gene-specific modifications to the ACMG/AMP (American College of Medical Genetics and Genomics and Association for Molecular Pathology) variant classification guidelines and validated such criteria through the pilot classification of 58 variants. RESULTS: The APC-specific criteria represented gene- and disease-informed specifications, including a quantitative approach to allele frequency thresholds, a stepwise decision tool for truncating variants, and semiquantitative evaluations of experimental and clinical data. Using the APC-specific criteria, 47% (27/58) of pilot variants were reclassified including 14 previous variants of uncertain significance (VUS). CONCLUSION: The APC-specific ACMG/AMP criteria preserved the classification of well-characterized variants on ClinVar while substantially reducing the number of VUS by 56% (14/25). Moving forward, the APC VCEP will continue to interpret prioritized lists of VUS, the results of which will represent the most authoritative variant classification for widespread clinical use.

Clinical study on risk factors and characteristics of Traditional Chinese Medicine syndrome of advanced adenomatous large intestine polyps / 国际中医中药杂志

Objective:To investigate the risk factors of adenomatous colorectal polyps in advanced stage.Methods:Retrospective cross-sectional study. A total of 400 hospitalized patients with colorectal polypectomy and pathological diagnosis of adenomatous polyps (Aps) were selected from December 2020 to December 2022 in Shenzhen Hospital of Beijing University of Chinese Medicine (Longgang), of which 107 patients with progressive adenomas and 293 patients with common adenomas were selected. General information of patients (name, gender, age, BMI), history of smoking, alcohol consumption, history of hypertension, history of diabetes mellitus, and results of 13C urea breath test were collected to analyze the risk factors for the development of adenomas in patients with progressive adenomas and their syndromic characteristics. Results:The distribution of male patients with advanced adenoma was significantly higher than that of common adenoma patients [70.09% (75/107) vs. 57.34% (168/293), P=0.021], and the ages were [(52.25±9.81) years vs. (48.41±10.23) years, P=0.001], BMI [(24.37±3.19) kg/m 2vs. (23.38±3.25) kg/m 2, P=0.007] significantly higher than those of ordinary adenoma patients. Intestinal damp-heat syndrome was the common witness type in both advanced and common adenomas, and the distribution of intestinal damp-heat syndrome in advanced adenomas was significantly higher than that in common adenomas [43.0% (46/107) vs. 32.1% (94/293); χ2=4.10, P=0.043]. The distribution of patients with alcohol drinking history in advanced adenomas was significantly higher than that in common adenomas [61.7% (66/107) vs. 39.3% (115/293); χ2=15.92, P<0.001]. The distribution of diabetic patients with advanced adenoma was significantly higher than that of common adenoma patients [29.9% (32/107) vs. 14.7% (43/293); χ2=19.94, P<0.001]. The infection rate of Hp in advanced adenoma patients was significantly higher than that in common adenoma patients [66.4% (71/107) vs. 44.7% (131/293); χ2=14.69, P<0.001]. Logistic regression analysis showed that age, BMI, male, intestinal damp-heat syndrome, drinking history, diabetes history and Hp infection were risk factors for the development of patients with progressive adenomas ( P<0.05 or P<0.01). Conclusion:Intestinal damp-heat syndrome is the key syndrome in patients with progressive adenoma, and age, BMI, male, history of alcohol consumption, history of diabetes mellitus and Hp infection are the risk factors for its development.

Improved Drug-Response Prediction Model of APC Mutant Colon Cancer Patient-Derived Organoids for Precision Medicine.

Colorectal cancer is the third most common cancer in the world, with an annual incidence of 2 million cases. The success of first-line chemotherapy plays a crucial role in determining the disease outcome. Therefore, there is an increasing demand for precision medicine to predict drug responses and optimize chemotherapy in order to increase patient survival and reduce the related side effects. Patient-derived organoids have become a popular in vitro screening model for drug-response prediction for precision medicine. However, there is no established correlation between oxaliplatin and drug-response prediction. Here, we suggest that organoid culture conditions can increase resistance to oxaliplatin during drug screening, and we developed a modified medium condition to address this issue. Notably, while previous studies have shown that survivin is a mechanism for drug resistance, our study observed consistent survivin expression irrespective of the culture conditions and oxaliplatin treatment. However, clusterin induced apoptosis inhibition and cell survival, demonstrating a significant correlation with drug resistance. This study's findings are expected to contribute to increasing the accuracy of drug-response prediction in patient-derived APC mutant colorectal cancer organoids, thereby providing reliable precision medicine and improving patient survival rates.

Trabid patient mutations impede the axonal trafficking of adenomatous polyposis coli to disrupt neurite growth.

ZRANB1 (human Trabid) missense mutations have been identified in children diagnosed with a range of congenital disorders including reduced brain size, but how Trabid regulates neurodevelopment is not understood. We have characterized these patient mutations in cells and mice to identify a key role for Trabid in the regulation of neurite growth. One of the patient mutations flanked the catalytic cysteine of Trabid and its deubiquitylating (DUB) activity was abrogated. The second variant retained DUB activity, but failed to bind STRIPAK, a large multiprotein assembly implicated in cytoskeleton organization and neural development. Zranb1 knock-in mice harboring either of these patient mutations exhibited reduced neuronal and glial cell densities in the brain and a motor deficit consistent with fewer dopaminergic neurons and projections. Mechanistically, both DUB-impaired and STRIPAK-binding-deficient Trabid variants impeded the trafficking of adenomatous polyposis coli (APC) to microtubule plus-ends. Consequently, the formation of neuronal growth cones and the trajectory of neurite outgrowth from mutant midbrain progenitors were severely compromised. We propose that STRIPAK recruits Trabid to deubiquitylate APC, and that in cells with mutant Trabid, APC becomes hyperubiquitylated and mislocalized causing impaired organization of the cytoskeleton that underlie the neuronal and developmental phenotypes.

Integrated genotype-phenotype analysis of familial adenomatous polyposis-associated hepatocellular adenomas.

Familial adenomatous polyposis (FAP) is an autosomal dominant syndrome caused by a germline mutation in the adenomatous polyposis coli (APC) gene, characterized by numerous colorectal adenomas. In addition, FAP patients may develop extraintestinal manifestations. Several cases of hepatocellular adenomas (HCA) detected accidentally in FAP patients have raised the so-far unsolved question of whether they represent a specific manifestation of FAP or a mere coincidence. To investigate the incidence of liver tumors in FAP patients, we analyzed our diagnostic database from 1991 to 2021. Among the 58 hepatic mass lesions identified, five HCAs occurring in three patients with FAP were identified, and comprehensive morphological, immunohistological, and molecular analysis employing targeted next-generation sequencing was conducted for characterization. The HCAs in this study showed no cytological or histological atypia. They displayed a diffuse, strong positivity for glutamine synthetase but no nuclear beta-catenin immunostaining. In two patients, the adenomas showed moderate immunoreactivity against serum amyloid A. Consistent with the diagnosis of FAP, molecular profiling revealed a pathogenic germline mutation of the APC gene in all analyzed adenomas as well as deleterious somatic second hits. All somatic mutations were localized between codons 1345 and 1577. No mutations were found in the catenin beta 1 gene. HCA in FAP patients can be a specific, although rare, neoplastic manifestation of this inborn disease and represents a distinct subgroup of HCAs. These benign tumors represent an important differential diagnosis for hepatic metastases in FAP patients and require adequate clinical and molecular (diagnostic) assessments for optimal patient guidance.

Usefulness of genotyping APC gene for individualizing management of patients with familial adenomatous polyposis.

BACKGROUND: Colorectal polyp burden is crucial for the management of patients with familial adenomatous polyposis (FAP). However, accurate evaluation of polyp burden is difficult to standardize. This study aimed to examine the possible utility of genotype-oriented management of colorectal neoplasms in patients with FAP. METHODS: Clinicopathological data from genetically proven patients with FAP was analyzed using the database of a nationwide retrospective Japanese multicenter study. The cumulative incidence of CRC was evaluated between different genotype groups. Genotype-1 were defined as germline variants on attenuated FAP-associated regions (codons 1-177, alternative splice site of exon 10 (codon 312), 1581-2843) and Genotype-2 as the other variants. Weibull and Joinpoint analyses were performed to determine the annual percentage changes in CRC risk. RESULTS: Overall, 69 men and 102 women were included. Forty-eight patients underwent colorectal resection for the first CRC, and five patients underwent resection for first cancer in the remnant anorectal segment after prophylactic surgery. The 70-year cumulative incidence of CRC in all patients was 59.3%. Patients with Genotype-1 (n = 23) demonstrated a lower risk of CRC stages II-IV than those with Genotype-2 (n = 148, P = 0.04). The risk of stage II-IV CRC was estimated to increase markedly at the age of 49 years in the Genotype-1 patients and 34 years in the Genotype-2 patients, respectively. CONCLUSIONS: Different interventional strategies based on genotypes may be proposed for the clinical management of patients with FAP. This policy needs to be validated in further prospective studies focusing on long-term endoscopic intervention and optimal age at prophylactic (procto)colectomy.

Genotype-phenotype correlation for extracolonic aggressive phenotypes in patients with familial adenomatous polyposis.

Familial adenomatous polyposis (FAP) patients develop various life-threatening extracolonic comorbidities that appear individually or within a family. This diversity can be explained by the localization of the adenomatous polyposis coli (APC) variant, but few reports provide definitive findings about genotype-phenotype correlations. Therefore, we investigated FAP patients and the association between the severe phenotypes and APC variants. Of 247 FAP patients, 126 patients from 85 families identified to have APC germline variant sites were extracted. These sites were divided into six groups (Regions A to F), and the frequency of severe comorbidities was compared among the patient phenotypes. Of the 126 patients, the proportions of patients with desmoid tumor stage ≥III, number of FGPs ≥1000, multiple gastric neoplasms, gastric neoplasm with high-grade dysplasia, and Spigelman stage ≥III were 3%, 16%, 21%, 12%, and 41%, respectively, while the corresponding rates were 30%, 50%, 70%, 50%, and 80% in patients with Region E (codons 1398-1580) variants. These latter rates were significantly higher than those for patients with variants in other regions. Moreover, the proportion of patients with all three indicators (desmoid tumor stage ≥III, number of FGPs ≥1000, and Spigelman stage ≥III) was 20% for those with variants in Region E and 0% for those with variants in other regions. Variants in Region E indicate aggressive phenotypes, and more intensive management is required.

When You Come to a Fork in the Road, Take It: Wnt Signaling Activates Multiple Pathways through the APC/Axin/GSK-3 Complex.

The Wnt signaling pathway is a highly conserved regulator of metazoan development and stem cell maintenance. Activation of Wnt signaling is an early step in diverse malignancies. Work over the past four decades has defined a "canonical" Wnt pathway that is initiated by Wnt proteins, secreted glycoproteins that bind to a surface receptor complex and activate intracellular signal transduction by inhibiting a catalytic complex composed of the classical tumor suppressor Adenomatous Polyposis Coli (APC), Axin, and Glycogen Synthase Kinase-3 (GSK-3). The best characterized effector of this complex is ß-catenin, which is stabilized by inhibition of GSK-3, allowing ß-catenin entrance to the nucleus and activation of Wnt target gene transcription, leading to multiple cancers when inappropriately activated. However, canonical Wnt signaling through the APC/Axin/GSK-3 complex impinges on other effectors, independently of ß-catenin, including the mechanistic Target of Rapamycin (mTOR), regulators of protein stability, mitotic spindle orientation, and Hippo signaling. This review focuses on these alternative effectors of the canonical Wnt pathway and how they may contribute to cancers.

T cell migration and effector function differences in familial adenomatous polyposis patients with APC gene mutations.

Familial adenomatous polyposis (FAP) is an inherited disease characterized by the development of large number of colorectal adenomas with high risk of evolving into colorectal tumors. Mutations of the Adenomatous polyposis coli (APC) gene is often at the origin of this disease, as well as of a high percentage of spontaneous colorectal tumors. APC is therefore considered a tumor suppressor gene. While the role of APC in intestinal epithelium homeostasis is well characterized, its importance in immune responses remains ill defined. Our recent work indicates that the APC protein is involved in various phases of both CD4 and CD8 T cells responses. This prompted us to investigate an array of immune cell features in FAP subjects carrying APC mutations. A group of 12 FAP subjects and age and sex-matched healthy controls were studied. We characterized the immune cell repertoire in peripheral blood and the capacity of immune cells to respond ex vivo to different stimuli either in whole blood or in purified T cells. A variety of experimental approaches were used, including, pultiparamater flow cytometry, NanosString gene expression profiling, Multiplex and regular ELISA, confocal microscopy and computer-based image analyis methods. We found that the percentage of several T and natural killer (NK) cell populations, the expression of several genes induced upon innate or adaptive immune stimulation and the production of several cytokines and chemokines was different. Moreover, the capacity of T cells to migrate in response to chemokine was consistently altered. Finally, immunological synapses between FAP cytotoxic T cells and tumor target cells were more poorly structured. Our findings of this pilot study suggest that mild but multiple immune cell dysfunctions, together with intestinal epithelial dysplasia in FAP subjects, may facilitate the long-term polyposis and colorectal tumor development. Although at an initial discovery phase due to the limited sample size of this rare disease cohort, our findings open new perspectives to consider immune cell abnormalities into polyposis pathology.

Identification of a novel CNV at the APC gene in a Chinese family with familial adenomatous polyposis.

Introduction: Familial adenomatous polyposis (FAP) is the second most commonly inherited colorectal cancer (CRC) predisposition caused by germline mutations within the adenomatous polyposis coli (APC) gene. The molecular defects and clinical manifestations of two FAP families were analyzed, and individual prevention strategies suitable for mutation carriers in different families were proposed. Methods and results: The pathogenic gene mutations were identified among the two families using whole-exome sequencing and verified with Sanger sequencing or quantitative polymerase chain reaction (qPCR). One novel (GRCh37:Chr5: 112145676-112174368, del, 28,692 bp) and a known (c.C847T:p.R283X) mutation in the APC gene were pathogenic mutations for FAP, according to the sequencing data and tumorigenesis pattern among the family members. The two mutations led to a premature translational stop signal, synthesizing an absent or disrupted protein product. Conclusion: Our findings expand the known germline mutation spectrum of the APC gene among the Chinese population. This reaffirms the importance of genetic testing in FAP. Genetic consultation and regular follow-ups are necessary for the individualized treatment of cancer-afflicted families with APC expression deficiency. Additional work is required to develop safe and effective chemotherapy and immunotherapy for FAP based on the mutation type.

First Evidence of Familial Transmission of Hereditary Gastrointestinal Polyposis Associated with Germline APC Variant in Jack Russell Terriers.

Jack Russell terriers (JRTs) with gastrointestinal (GI) neoplastic polyps have been recently reported to harbor an identical germline variant in the adenomatous polyposis coli (APC) gene, c.[462_463delinsTT], in the heterozygous state, which indicates that this disease is an autosomal dominant hereditary disorder. Many individual cases of this disease have been observed in clinical practice; however, familial transmission has not been demonstrated due to the difficulty in tracing the family members of household dogs, especially after the disease's onset in adulthood. Recently, we encountered two cases of GI polyposis in maternal half sisters. These two cases facilitated the identification of additional relatives spanning three generations, including parents, full and half siblings of the dam (aunt and uncle), littermate and non-littermate siblings, and a nephew. Genetic analysis revealed that 11 of the 14 examined JRTs in this family carried the heterozygous germline APC variant, and eight dogs with the variant already had a current and/or past medical history of GI neoplastic polyps. Some cases in the family showed significantly more severe disease phenotypes than those initially reported, suggesting that the severity of this disease can vary considerably among individuals. Moreover, familial aggregation of severe cases suggested that the genetic modifier involved in increasing severity may have been transmitted in this family in addition to the germline APC variant. Furthermore, in addition to this family, we reported two other families of JRTs affected by hereditary GI polyposis that consisted of five full and half siblings and a mother-daughter pair, respectively. These findings unequivocally establish the transgenerational transmission of hereditary GI polyposis associated with the germline APC variant in JRT lineages.

[Hereditary colorectal carcinogenesis]. / Hereditäre kolorektale Karzinogenese.

Hereditary cancer is characterized by the development of certain cancer types in combination with pathogenic germline mutations in genes known to predispose to these cancer types. Familial cancer differs from hereditary cancer in that no predisposing germline mutation is detected in affected families. However, familial cancer may have a genetic background of as yet unknown origin. Colorectal cancer is unique among human tumors since almost all cancers derive from macroscopically visible benign polypoid precursors. Molecular mechanisms of precursor development differ from that of malignant transformation. Hereditary colorectal cancer can be categorized into polypous and non-polypous predispositions. While the former elevate cancer risk by increasing the number of cancer precursors, the latter elevate cancer risk by increasing the likeliness of malignant transformation. It is the pathologist's responsibility to use morphologic criteria in combination with clinical data in order to raise suspicion of hereditary tumorigenesis and recommend genetic counselling. This article summarizes the current knowledge on hereditary colorectal cancer.

The preventive and therapeutic effects of anthocyanins on colorectal cancer: A comprehensive review based on up-to-date experimental studies.

Colorectal cancer (CRC) is the second most lethal and the third most diagnosed type of cancer worldwide. More than 75% of CRC cases are sporadic and lifestyle-related. Risk factors include diet, physical inactivity, genetics, smoking, alcohol, changes in the intestinal microbiota, and inflammation-related diseases such as obesity, diabetes, and inflammatory bowel diseases. The limits of conventional treatments (surgery, chemotherapy, radiotherapy), as demonstrated by the side effects and resistance of many CRC patients, are making professionals search for new chemopreventive alternatives. In this context, diets rich in fruits and vegetables or plant-based products, which contain high levels of phytochemicals, have been postulated as complementary therapeutic options. Anthocyanins, phenolic pigments responsible for the vivid colors of most red, purple, and blue fruits and vegetables, have been shown protective effects on CRC. Berries, grapes, Brazilian fruits, and vegetables such as black rice and purple sweet potato are examples of products rich in anthocyanins, which have been able to reduce cancer development by modulating signaling pathways associated with CRC. Therefore, this review has as main objective to present and discuss the potential preventive and therapeutic effects of anthocyanins present in fruits and vegetables, in plant extracts, or in their pure form on CRC, taking into account up-to-date experimental studies (2017-2023). Additionally, a highlight is given towards the mechanisms of action of anthocyanins on CRC.

Future therapeutic implications of new molecular mechanism of colorectal cancer.

High incidence (10.2%) and mortality (9.2%) rates led to the ranking of colorectal cancer (CRC) as the second most malignant tumor spectrum worldwide in 2020. Treatment strategies are becoming highly dependent on the molecular characteristics of CRC. The classical theories accept two models depicting the origin of CRC: The progression of adenoma to cancer and transformation from serrated polyps to cancer. However, the molecular mechanism of CRC development is very complex. For instance, CRCs originating from laterally spreading tumors (LST) do not adhere to any of these models and exhibit extremely serious progression and poor outcomes. In this article, we present another possible pathway involved in CRC development, particularly from LST, with important molecular characteristics, which would facilitate the design of a novel strategy for targeted therapy.