Nonsense suppression induces read-through of a novel BMPR1A variant in a Chinese family with hereditary colorectal cancer

BACKGROUND

BMPR1A-mediated signaling transduction plays an essential role in intestinal growth. Variations of BMPR1A lead to a rare autosomal dominant inherited juvenile polyposis syndrome (JPS) with high probability of developing into colorectal cancer (CRC). Nonsense and frameshift variations, generating premature termination codons (PTCs), are the most pathogenic variants in the BMPR1A gene.

OBJECTIVE

This study aimed to investigate the molecular genetic etiology in a Chinese family with three generations of CRC.

METHODS

Pathogenic variants of 18 known CRC susceptibility genes were examined in a Chinese CRC family through multigene panel testing using the next-generation sequencing platform. The candidate gene variant was validated in the family members by Sanger sequencing. Potential biological functions of the gene variant were further investigated in the RKO colon cancer cell line.

RESULTS

A novel nonsense variant (c.1114A > T, p.Lys372*) of BMPR1A was identified in the CRC family. This variant generated a PTC at the kinase domain and caused nonsense-mediated mRNA decay. Read-through inducing reagents G418 and PTC124 partially restored BMPR1A expression and its following signaling pathway.

CONCLUSION

The identification of the novel BMPR1A variant enriched the genotype-phenotype spectrum of BMPR1A. Meanwhile, our finding also provided support for future PTC-targeting therapy for BMPR1A-mediated JPS and CRC.

Cancer risk and mortality in patients with solitary juvenile polyps-A nationwide cohort study with matched controls

INTRODUCTION

The risk of cancer in patients with solitary colorectal juvenile polyps (JPs) is poorly investigated and several studies have reported polyps with dysplastic and adenomatous alterations. We aimed to investigate the long-term risk of cancer and mortality in these patients by merging data from national registers and comparing them to a matched control cohort.

MATERIALS AND METHODS

Patients with a solitary JP were identified in The Danish National Pathology Register and Data Bank (DNPR). The included patients were matched on sex, age, and place of birth with 50 controls. The groups were then analyzed for risk of cancer using the Danish Cancer Registry and mortality using the Danish Cause of Death Registry.

RESULTS

We identified 1781 patients with solitary JPs and matched them with 83,713 controls. The mean follow-up time was 7.65 years for cases and 7.36 years for controls. The risk of cancer, including colorectal cancer, did not differ for the two groups and when adjusting for sex and year of birth, the hazard ratio (HR) was 1.15 (confidence interval [CI] 95% 0.94-1.41, p = 0.162). There was no increased risk of death (HR: 1.07, CI 95% 0.88-1.30, p = 0.486). The risk did not differ for different age groups or sex.

CONCLUSION

There is no increased risk of cancer or mortality for patients with solitary colorectal JPs. Thus, endoscopic follow-up may be safely omitted in these patients.

A novel germline SMAD4 variant detected in a Japanese family with juvenile polyposis syndrome and hereditary hemorrhagic telangiectasia

Juvenile polyposis syndrome (JPS) is an autosomal dominant, inherited disorder caused by pathogenic germline variants of mainly SMAD4 or BMPR1A genes. Some patients with JPS, especially with SMAD4 variants, also develop hereditary, hemorrhagic telangiectasia (HHT). HHT is also an autosomal dominant inherited disorder. Herein, we identified a novel germline pathogenic variant of the SMAD4 in a Japanese family with JPS and HHT. A six-base pair deletion in the SMAD4 gene (NM_005359.6:c.1495_1500delTGCATA) was identified in the patients. Two amino acids are deleted from SMAD4 protein (p.Cys499_Ile500del), which are located in MSH2 domain essential for the binding with SMAD3. This is a novel variant that has not been registered in any database surveyed. Amino acid structural analysis predicted significant changes in the secondary and three-dimensional structures in the vicinity of the two amino acids' deletion. The variant is classified as 'Likely Pathogenic' according to the American College of Medical Genetics and Genomics guidelines.

Gastrointestinal Bleeding in the Setting of Juvenile Polyposis Syndrome Due to SMAD4 Mutation

A 27-year-old female presented at 13 weeks' gestation with epigastric pain and anemia requiring blood and iron transfusions but no family history of gastrointestinal malignancy. Upper endoscopy revealed a giant circumferential polyp and associated hyperplastic-appearing polyps in the proximal stomach. Biopsies revealed hyperplasia with lamina propria eosinophils. She was supported with intermittent transfusions until labor was induced at 34 weeks' gestation. Total gastrectomy was performed at seven weeks post-partum. Final pathology revealed multiple hamartomatous polyps without malignancy. Her anemia resolved postoperatively. Genetic testing revealed mutation of the SMAD4 gene and Juvenile Polyposis Syndrome. JPS is caused by germline mutations in the SMAD4 or BMPR1A genes and is characterized by hamartomatous polyps in the gastrointestinal tract. While most polyps are benign, malignant transformation can occur. One should have low threshold to send patients for genetic screening when multiple polyps are found in a young patient, even without family history.

Re-recognition of BMPR1A-related polyposis: beyond juvenile polyposis and hereditary mixed polyposis syndrome

Background

Bone morphogenetic protein receptor type 1A (BMPR1A) is responsible for two individual Mendelian diseases: juvenile polyposis syndrome and hereditary mixed polyposis syndrome 2, which have overlapping phenotypes. This study aimed to elucidate whether these two syndromes are just two subtypes of a single syndrome rather than two isolated syndromes.

Methods

We sequenced the BMPR1A gene in 186 patients with polyposis and colorectal cancer, and evaluated the clinicopathological features and phenotypes of the probands and their available relatives with BMPR1A mutations.

Results

BMPR1A germline mutations were found in six probands and their three available relatives. The numbers of frameshift, nonsense, splice-site, and missense mutations were one, one, two, and two, respectively; two of the six mutations were novel. Typical juvenile polyps were found in only three patients. Two patients had colorectal cancer rather than any polyps.

Conclusions

Diseases in BMPR1A germline mutation carriers vary from mixed polyposis to sole colorectal cancer, and typical juvenile polyps do not always occur in these carriers. The variety of phenotypes reflected the features of BMPR1A-mutation carriers, which should be recognized as a spectrum of one syndrome. Genetic testing may be a good approach to identifying BMPR1A-related syndromes.

Juvenile polyposis syndrome: A case report

Juvenile polyposis syndrome (JPS) is an autosomal dominant disease that is characterized by multiple hamartomatous polyps. Patients with JPS are at increased risk for developing colorectal and gastric cancer. JPS was diagnosed by endoscopy and histology, and the patient underwent surgery, total proctocolectomy and ileal pouch-anal anastomosis.

A case report of adult juvenile polyposis syndrome with SMAD4 pathogenic variant

Background

Juvenile polyposis syndrome (JPS) is a rare autosomal dominant disorder that is a type of hamartomatous polyp syndrome, and its incidence rate is approximately 1/100000. The main clinical feature is the presence of multiple juvenile polyps in the gastrointestinal tract, most often in the colorectal tract. We present a case of juvenile polyposis syndrome with massive gastric polyposis.

Case presentation

A 50-year-old male was admitted to the hospital due to abdominal distension and poor appetite. Gastroscopy revealed a large number of gastric polyps. Pathological findings revealed gastric juvenile polyps. Genetic testing revealed that he and his brother both carried SMAD4: c.266_269del germline pathogenic variant. The final diagnosis was juvenile polyposis syndrome of the stomach. He once suffered from colon cancer and bladder cancer. One of his brothers died of colon cancer, and the other brother suffered from colon polyps.

Conclusions

Gastric involvement in juvenile polyposis syndrome is relatively rare. When massive gastric polyposis is found, gene detection should be carried out as soon as possible, so that rapid diagnosis and treatment can be obtained.

Clinical Guidelines for Diagnosis and Management of Juvenile Polyposis Syndrome in Children and Adults-Secondary Publication

Juvenile polyposis syndrome (JPS) is a rare disease characterized by multiple hamartomatous polyps within the gastrointestinal tract. SMAD4 or BMPR1A is known as a causative gene of JPS. Approximately 75% of newly diagnosed cases have an autosomal-dominantly inherited condition, whereas 25% are sporadic without previous history of polyposis in the family pedigree. Some patients with JPS develop gastrointestinal lesions in childhood and require continuous medical care until adulthood. JPS is classified into three categories according to phenotypic features of polyp distributions, including generalized juvenile polyposis, juvenile polyposis coli, and juvenile polyposis of the stomach. Juvenile polyposis of the stomach is caused by germline pathogenic variants of SMAD4 with a high risk leading to gastric cancer. Pathogenic variants of SMAD4 are also associated with hereditary hemorrhagic telangiectasia-JPS complex, inducing regular cardiovascular survey. Despite growing concerns regarding the managing JPS in Japan, there are no practical guidelines. To address this situation, the guideline committee was organized by the Research Group on Rare and Intractable Diseases granted by the Ministry of Health, Labor and Welfare involving specialists from multiple academic societies. The present clinical guidelines explain the principles in the diagnosis and management of JPS with three clinical questions and corresponding recommendations based on a careful review of the evidence and involve incorporating the concept of the Grading of Recommendations, Assessment, Development, and Evaluation system. Herein, we present the clinical practice guidelines of JPS to promote seamless implementation of accurate diagnosis and appropriate management of pediatric, adolescent, and adult patients with JPS.

Hereditary hemorrhagic telangiectasis with juvenile polyposis syndrome: a case report

Hereditary hemorrhagic telangiectasis (HHT) and juvenile polyposis syndrome (JPS) are both relatively rare hereditary disorders. It has been reported that patients with SMAD4 mutations may suffer from both HHT and JPS, defined as JPS/HHT. To improve the understanding and diagnosis of these diseases, we herein report a case of a 17-year-old male with abdominal pain and hematochezia. Low-tension computed tomography (CT) of the small intestine showed intussusception. Combined with the patient's medical history of nasal bleeding and pulmonary arteriovenous fistula (pAVF) embolism, a final diagnosis of JPS/HHT was reached, according to the Curaçao Diagnostic Criteria. The possibility of JPS/HHT should be considered in patients with epistaxis and intussusception.

A New SMAD4 Splice Site Variant in a Three-Generation Italian Family with Juvenile Polyposis Syndrome

Juvenile polyposis syndrome (JPS) is an autosomal dominant disorder characterized by hyperplastic polyps in the upper and lower gastrointestinal (GI) tract with a high risk of developing GI cancers. We have described a three-generation Italian family with all the spectrum of SMAD4 phenotype. A multigene panel test was performed on the genomic DNA of the proband by next-generation sequencing, including genes related to hereditary GI tumor syndromes. Molecular analysis revealed the presence of the c.1140-2A>G substitution in the SMAD4 gene, a novel splice variant that has never been described before. Our family is remarkable in that it illustrates the variable expressivity of the SMAD4 phenotype within the same family. The possibility of phenotype variability should also be considered within family members carrying the same mutation. In JPS, a timely genetic diagnosis allows clinicians to better manage patients and to provide early surveillance and intervention for their asymptomatic mutated relatives in the early decades of life.

Endoscopic Surveillance in Patients with the Highest Risk of Gastric Cancer: Challenges and Solutions

Gastric cancer is one of the most significant causes of cancer-related morbidity and mortality worldwide. Recognized modifiable risk factors include Helicobacter pylori infection, geographic location, select dietary factors, tobacco use and alcohol consumption. In addition, multiple hereditary cancer predisposition syndromes are associated with significantly elevated gastric cancer risk. Endoscopic surveillance in hereditary gastric cancer predisposition syndromes has the potential to identify gastric cancer at earlier and more treatable stages, as well as to prevent development of gastric cancer through identification of precancerous lesions. However, much uncertainty remains regarding use of endoscopic surveillance in hereditary gastric cancer predisposition syndromes, including whether or not it should be routinely performed, the surveillance interval and age of initiation, cost-effectiveness, and whether surveillance ultimately improves survival from gastric cancer for these high-risk individuals. In this review, we outline the hereditary gastric cancer predisposition syndromes associated with the highest gastric cancer risks. Additionally, we cover current evidence and guidelines addressing hereditary gastric cancer risk and surveillance in these syndromes, along with current challenges and limitations that emphasize a need for continued research in this field.

A Rare Case of Juvenile Polyposis Syndrome Mimicking Ménétrier's Disease

There is a wide differential diagnosis within polyposis syndromes. Our case represents an interesting and diagnostically challenging diagnosis involving a 41-year-old male who presented with an incidental gastric mass on imaging and a colonic mass seen on colonoscopy. Following multiple endoscopic evaluations, histological analysis, and genetic testing, the patient was ultimately diagnosed with juvenile polyposis syndrome (JPS)/hereditary hemorrhagic telangiectasia (HHT) despite the initial suspicion for Ménétrier's disease. His disease course was complicated by an acute upper extremity thrombus and diagnosis of colorectal carcinoma. This case highlights the importance of a thorough evaluation when polyposis syndromes are suspected. Prompt and accurate diagnosis can aid in the treatment, surveillance, and prevention of colorectal carcinoma.

A novel BMPR1A mutation affects mRNA splicing in juvenile polyposis syndrome

BACKGROUND

Juvenile polyposis syndrome (JPS) is one of the hereditary polyposis syndromes caused by abnormal regulation of transforming growth factor β signaling because of mutations in BMPR1A and SMAD4. Juvenile polyposis syndrome patients with SMAD4 mutations develop cardiovascular events, whereas those with BMPR1A usually do not. Analysis of genetic mutations in JPS patients can be helpful in devising suitable strategies for medical management. In this study, we demonstrate the pathogenicity of a novel intronic mutation in BMPR1A using mRNA extracted from colonic mucosa of a boy with JPS.

METHODS

Genomic DNA extracted from peripheral blood and total RNA isolated from the colonic mucosa were used for DNA sequencing and reverse transcription polymerase chain reaction (RT-PCR) analyses, respectively.

RESULTS

A 13-year-old boy, with no previous medical history, presented to the hospital complaining of bloody stools. Colonoscopy revealed multiple polyps in the colon, and the resected polyps were compatible with juvenile polyps. Sequencing analysis revealed a novel intronic mutation (c.778+5G>C) in BMPR1A. Reverse transcription polymerase chain reaction analysis of RNA extracted from the colonic mucosa showed an aberrant splicing form of BMPR1A. Trio analysis showed that his mother also had the same BMPR1A mutation. She was diagnosed with cancer of the cecum and polyposis of the colon at the age of 41.

CONCLUSION

We demonstrate the presence of a novel BMPR1A intronic mutation that exhibits splicing abnormality in a family with JPS. Further research and development will help elucidate the genotype-phenotype relationship in JPS.

Importance of early detection of juvenile polyposis syndrome: A case report and literature review

RATIONALE

Juvenile polyposis syndrome (JPS) is a rare genetic gastrointestinal disorder with hidden and variable clinical features. Early detection is crucial for good prognosis.

PATIENT CONCERNS

A 20-year-old female went to hospital for fever, and was unexpectedly diagnosed as JPS during treatment. She reported no clinical signs or family history of JPS.

DIAGNOSIS

Blood routine examination on hospital admission suggested a moderate anemia. Bone marrow cytology and leukemia fusion gene test were performed to rule out leukemia. Other examinations including ultrasound and computed tomography were also conducted for differential diagnosis. Further electronic colonoscopy identified more than 20 pedicle polyps located at her ileocecum and rectum. Mutation analysis detected a novel de novo pathogenic variant, c.910C>T (p.Gln304Ter) within bone morphogenetic protein receptor type 1A gene, establishing the diagnosis of JPS.

INTERVENTIONS

The patient was treated with endoscopic interventions. We also provided a genetic counseling for this family.

OUTCOMES

The patient's polyps were removed, some of which already had adenomatous changes. The patient received surveillance of hereditary colorectal cancer according to guidelines.

LESSONS

Variable features and lack of family history probably lead to a great underestimation of potential JPS population. It is recommended to perform genetic testing by a multigene panel in individuals who have suspected symptoms of polyposis.

Non-familial Juvenile Polyposis Syndrome Presenting as Rectal Prolapse: An Unusual Presentation of a Rare Disease

Juvenile polyposis syndrome is a rare inherited disorder that afflicts the gastrointestinal system. It usually occurs as a result of gene mutations; to date, several gene mutations, including those involving the bone morphogenetic protein receptor type IA (BMPR1A) gene, have been implicated in heralding the onset of the ailment. The disease is characterized by the infiltration of the gastrointestinal system with numerous hamartomas, which are predominantly benign. However, if left untreated, the hamartomas can undergo malignant transformations. Timely diagnosis and prompt surgical intervention are, therefore, imperative in portending favorable disease outcomes. We hereby delineate the case of a patient who presented with rectal prolapse and bleeding per rectum. Further diagnostic workup revealed the presence of polyps throughout the colon and the rectum, thereby insinuating a diagnosis of non-familial juvenile polyposis syndrome. The patient was managed through open surgery and continues to do well with no indications of disease recurrence. 

Chromosomal translocation disrupting the SMAD4 gene resulting in the combined phenotype of Juvenile polyposis syndrome and Hereditary Hemorrhagic Telangiectasia

Background

Patients with germline variants in SMAD4 can present symptoms of both juvenile polyposis syndrome (JPS) and Hereditary Hemorrhagic Telangiectasia (HHT): JP‐HHT syndrome. Next‐Generation Sequencing (NGS) techniques disclose causative sequence variants in around 90% of HHT patients fulfilling the Curaçao criteria. Here we report a translocation event involving SMAD4 resulting in JP‐HHT.

Methods

A patient fulfilling the Curaçao criteria was analyzed for variants in ENG, ACVRL1, and SMAD4 using standard techniques. Whole‐genome sequencing (WGS) using both short‐read NGS technology and long‐read Oxford Nanopore technology was performed to define the structural variant and exact breakpoints.

Results

No pathogenic variant was detected in ENG, ACVRL1, or SMAD4 in DNA extracted from blood. Due to abortus habitualis, the proband´s daughter was submitted for chromosomal analysis, and a cytogenetically balanced chromosomal reciprocal translocation t(1;18)(p36.1;q21.1) was detected in the daughter and the patient. The balanced translocation segregated with both gastrointestinal cancer and HHT in the family. WGS provided the exact breakpoints of the reciprocal translocation proving disruption of the SMAD4 gene.

Discussion

A disease‐causing reciprocal translocation between chromosome 1 and 18 with a breakpoint in the SMAD4 locus co‐segregated with JP‐HHT in an extended family. This observation warrants further analysis for chromosomal rearrangements in individuals with clinical HHT or JP‐HHT of unknown cause.

A novel germline BMPR1A variant (c.72_73delGA) in a Japanese family with hereditary mixed polyposis syndrome

Hereditary mixed polyposis syndrome (HMPS) is a rare autosomal dominant disorder characterized by a mixture of typical and/or atypical juvenile polyps, adenomas and hyperplastic polyps, resulting in an increased risk of colorectal cancer. In HMPS, four different germline BMPR1A variants from five unrelated families have been reported. This study is the first to report HMPS within a Japanese family. The proband underwent repeated colonoscopic polypectomies over a 5-year period, since the age of 67. Histological examination of these resected polyps revealed adenomas, juvenile-like polyps and hyperplastic changes. Genetic testing was conducted to identify the causative genes for hereditary gastrointestinal cancer syndromes, including BMPR1A. We detected a germline variant, c.72_73delGA, in BMPR1A. The proband’s elder brother, younger sister and nephew have also undergone repeated colonoscopic polypectomies at other clinics. His sister and nephew underwent genetic testing, and the same BMPR1A variant was identified.

Disease expression in juvenile polyposis syndrome: a retrospective survey on a cohort of 221 European patients and comparison with a literature-derived cohort of 473 SMAD4/BMPR1A pathogenic variant carriers

Purpose

Juvenile polyposis syndrome (JPS) is a rare, autosomal-dominantly inherited cancer predisposition caused in approximately 50% of cases by pathogenic germline variants in SMAD4 and BMPR1A. We aimed to gather detailed clinical and molecular genetic information on JPS disease expression to provide a basis for management guidelines and establish open access variant databases.

Methods

We performed a retrospective, questionnaire-based European multicenter survey on and established a cohort of SMAD4/BMPR1A pathogenic variant carriers from the medical literature.

Results

We analyzed questionnaire-based data on 221 JPS patients (126 kindreds) from ten European centers and retrieved literature-based information on 473 patients. Compared with BMPR1A carriers, SMAD4 carriers displayed anemia twice as often (58% vs. 26%), and exclusively showed overlap symptoms with hemorrhagic telangiectasia (32%) and an increased prevalence (39% vs. 13%) of gastric juvenile polyps. Cancer, reported in 15% of JPS patients (median age 41 years), mainly occurred in the colorectum (overall: 62%, SMAD4: 58%, BMPR1A: 88%) and the stomach (overall: 21%; SMAD4: 27%, BMPR1A: 0%).

Conclusion

This comprehensive retrospective study on genotype–phenotype correlations in 694 JPS patients corroborates previous observations on JPS in general and SMAD4 carriers in particular, facilitates recommendations for clinical management, and provides the basis for open access variant SMAD4 and BMPR1A databases.

Polyp Characteristics of Nonsyndromic and Potentially Syndromic Juvenile Polyps: A Retrospective Cohort Analysis

BACKGROUND

Juvenile polyps (JPs) are the most common gastrointestinal polyps diagnosed in children. There is paucity of evidence differentiating polyp burden groups and the presence and significance of neoplastic changes.

METHODS

A retrospective chart review of patients, ages birth through 18 years with nonsyndromic JPs was performed from 2003 to 2017. Abstracted data included basic demographics, age, clinical presentation, colonoscopy findings, and pathology report. Slides of polyps with neoplasia were reviewed by a pathologist.

RESULTS

A total of 213 subjects underwent 326 procedures and 435 polypectomies. Subjects with positive family history, positive gene mutations, or numerous (>10) polyps were excluded. Groups were defined by polyp number (1, 2-4, 5-10). Polyp recurrence on repeat colonoscopy was significantly related to polyp burden (1 polyp: 1.5%/2-4 polyps 19.2%/5-10 polyps 82.6%: P < 0.001). Polyp distribution was significantly different amongst different groups with isolated polyps favoring a distal distribution. JPs harboring adenomatous foci were reported in 26 (12%) patients. JPs harboring adenomatous foci were significantly more likely to be proximally distributed but the presence of adenomatous transformation within the polyps did not correlate with polyp number or the likelihood of polyp recurrence on repeat colonoscopy.

CONCLUSIONS

JP recurrence is positively and significantly related to polyp burden. JP harbored adenomatous changes independent of polyp number, underscoring a possible malignant potential in JPs. In the absence of a consistent genotype or pedigree, the presence of adenomatous transformation within JPs cannot be construed as a biomarker for syndromic juvenile polyposis.

Gastrointestinal Polyposis in Pediatric Patients

Gastrointestinal polyps are mucosal overgrowths that, if unchecked, can undergo malignant transformation. Although relatively uncommon in the pediatric age group, they can be the harbingers of multiorgan cancer risk and require close management and follow-up. Additionally, as many polyposis syndromes are inherited, appropriate genetic testing and management of relatives is vital for the health of the entire family. In this review, we discuss both common and uncommon childhood gastrointestinal polyposis syndromes in terms of clinical presentation, management, and surveillance. We also detail any additional malignancy risk and surveillance required in the pediatric age group (<21 years old). Through this review, we provide a framework for gastroenterologists to manage the multifaceted nature of pediatric polyposis syndromes.

A case report of hamartomatous polyposis in an individual with Neurofibromatosis type 1

Even in well-described genetic syndromes, such as neurofibromatosis type 1, expansion of the phenotype should be considered as a possible explanation for atypical presentations. However, it is critical to complete the evaluation for a potential dual diagnosis, as there could be significant prognostic and management implications.

Bone morphogenetic protein receptor signal transduction in human disease

Bone morphogenetic proteins (BMPs) are secreted cytokines that were initially discovered on the basis of their ability to induce bone. Several decades of research have now established that these proteins function in a large variety of physiopathological processes. There are about 15 BMP family members, which signal via three transmembrane type II receptors and four transmembrane type I receptors. Mechanistically, BMP binding leads to phosphorylation of the type I receptor by the type II receptor. This activated heteromeric complex triggers intracellular signaling that is initiated by phosphorylation of receptor‐regulated SMAD1, 5, and 8 (also termed R‐SMADs). Activated R‐SMADs form heteromeric complexes with SMAD4, which engage in specific transcriptional responses. There is convergence along the signaling pathway and, besides the canonical SMAD pathway, BMP‐receptor activation can also induce non‐SMAD signaling. Each step in the pathway is fine‐tuned by positive and negative regulation and crosstalk with other signaling pathways. For example, ligand bioavailability for the receptor can be regulated by ligand‐binding proteins that sequester the ligand from interacting with receptors. Accessory co‐receptors, also known as BMP type III receptors, lack intrinsic enzymatic activity but enhance BMP signaling by presenting ligands to receptors. In this review, we discuss the role of BMP receptor signaling and how corruption of this pathway contributes to cardiovascular and musculoskeletal diseases and cancer. We describe pharmacological tools to interrogate the function of BMP receptor signaling in specific biological processes and focus on how these agents can be used as drugs to inhibit or activate the function of the receptor, thereby normalizing dysregulated BMP signaling. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Juvenile Idiopathic Arthritis Associated with Combined JP-HHT Syndrome: A Novel Phenotype Associated with a Novel Variant in SMAD4

Juvenile polyposis (JP) syndrome is characterized by multiple hamartomatous polyps of the gastrointestinal tract. Hereditary hemorrhagic telangiectasia (HHT) is a vascular dysplasia characterized by telangiectasia in the skin, mucous membranes, and arteriovenous malformations in other organs. Individuals with JP-HHT syndrome have variable features of both rare disorders, attributed to heterozygous mutations in the SMAD4 gene. Systemic juvenile idiopathic arthritis (JIA) is a severe, chronic disease marked by arthritis and systemic inflammation for which the cause remains unknown. JIA has never been described in association with SMAD4 -related disease. We describe a case of JP-HHT syndrome with a novel SMAD4 variant, c.1052A > T (p.D351V), in which the child also had JIA manifestation.

Mosaicism: Implications for Genetic Counseling and Medical Management

Mosaicism describes the presence of two or more populations of cells with different genotypes in one individual that have developed from a single fertilized egg. This article reviews the various clinical presentations of mosaicism associated with hereditary cancer syndromes and the challenges in providing patients and their families with appropriate genetic testing, as well as provides recommendations for cancer presentation and early detection. Management of mosaicism is based on personal and family history, along with genetic testing results. 
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Juvenile polyposis syndrome: An unusual case report of anemia and gastrointestinal bleeding in young infant

BACKGROUND

Juvenile polyposis syndrome, a rare disorder in children, is characterized with multiple hamartomatous polyps in alimentary tract. A variety of manifestations include bleeding, intussusception, or polyp prolapse. In this study, we present an 8-month-old male infant of juvenile polyposis syndrome initially presenting with chronic anemia. To the best of our knowledge, this is the youngest case reported in the literature.

METHODS

We report a rare case of an 8-month-old male infant who presented with chronic anemia and gastrointestinal bleeding initially. Panendoscopy and abdominal computed tomography showed multiple polyposis throughout the entire alimentary tract leading to intussusception. Technetium-99m-labeled red blood cell (RBC) bleeding scan revealed the possibility of gastrointestinal tract bleeding in the jejunum. Histopathological examination on biopsy samples showed Peutz-Jeghers syndrome was excluded, whereas the diagnosis of juvenile polyposis syndrome was established.

RESULTS

Enteroscopic polypectomy is the mainstay of the treatment. However, polyps recurred and occupied the majority of the gastrointestinal tract in 6 months. Supportive management was given. The patient expired for severe sepsis at the age of 18 months.

CONCLUSION

Juvenile polyposis syndrome is an inherited disease, so it is not possible to prevent it. Concerning of its poor outcome and high mortality rate, it is important that we should increase awareness and education of the parents at its earliest stages.

Prevalence of thoracic aortopathy in patients with juvenile Polyposis Syndrome-Hereditary Hemorrhagic Telangiectasia due to SMAD4

Hereditary hemorrhagic telangiectasia (HHT) is characterized by abnormal vascular structures that may present as epistaxis, telangiectasias, and/or arteriovenous malformations. The genes associated with HHT (ACVRL1, ENG, and SMAD4) are members of the TGFβ pathway. Other syndromes associated with abnormalities in TGFβ signaling include Marfan syndrome, Loeys-Dietz syndrome and related disorders. These disorders have aortic disease as a prominent finding. While there are case reports of patients with HHT and aortopathy (dilatation/aneurysm, dissection, and rupture), this has not been systematically investigated. We conducted a retrospective chart review to determine the prevalence of aortopathy in an HHT cohort. Patients from a single institution were identified who met the Curacao Criteria for a clinical diagnosis of HHT and/or had a mutation in ACVRL1, ENG, or SMAD4 and underwent echocardiogram. Two-dimensional echocardiograms were reviewed by a single pediatric cardiologist, and data were collected on demographics, genotype, HHT features, aortic root measurements, past medical history, and family history. Z scores and nomograms were utilized to identify abnormal results. Twenty-six patients from 15 families (one ACVRL1, four ENG, eight SMAD4, and two clinical diagnoses) were included in the analysis. Aortopathy was found in 6/26 (23%) patients; all had SMAD4 mutations. In our cohort, 6/16 (38%) SMAD4 mutation carriers had evidence of aortopathy. These data suggest that aortopathy could be part of the spectrum of SMAD4-induced HHT manifestations. Routine aortic imaging, including measurements of the aorta, should be considered in patients with SMAD4 mutations to allow for appropriate medical and surgical recommendations.

Identification of coding exon 3 duplication in the BMPR1A gene in a patient with juvenile polyposis syndrome

Juvenile polyposis syndrome is an autosomal dominant inherited disorder characterized by multiple juvenile polyps arising in the gastrointestinal tract and an increased risk of gastrointestinal cancers, specifically colon cancer. BMPR1A and SMAD4 germline mutations have been found in patients with juvenile polyposis syndrome. We identified a BMPR1A mutation, which involves a duplication of coding exon 3 (c.230+452_333+441dup1995), on multiple ligation dependent probe amplification in a patient with juvenile polyposis syndrome. The mutation causes a frameshift, producing a truncated protein (p.D112NfsX2). Therefore, the mutation is believed to be pathogenic. We also identified a duplication breakpoint in which Alu sequences are located. These results suggest that the duplication event resulted from recombination between Alu sequences. To our knowledge, partial duplication in the BMPR1A gene has not been reported previously. This is the first case report to document coding exon 3 duplication in the BMPR1A gene in a patient with juvenile polyposis syndrome.

Juvenile polyposis syndrome

Juvenile polyposis syndrome (JPS) is an autosomal dominant predisposition to the occurrence of hamartomatous polyps in the gastrointestinal tract. Diagnosis of JPS is based on the occurrence of numerous colon and rectum polyps or any number of polyps with family history and, in the case of juvenile polyps, their occurrence also outside the large intestine. The JPS is caused by mutations in SMAD4 and BMPR1A. Products of the SMAD4 gene are involved in signal transduction in the transforming growth factor β pathway and BMPR1A protein is a receptor belonging to the family of transmembrane serine/threonine kinases. Both proteins are responsible for processes determining appropriate development of colonic mucosa. The JPS belongs to the group of hamartomatous polyposes. The hamartomatous polyposis syndromes constitute a group of diseases in which manifestations differ slightly and only molecular diagnostics gives the possibility of verifying the clinical diagnosis.

Prevalence of germline PTEN, BMPR1A, SMAD4, STK11, and ENG mutations in patients with moderate-load colorectal polyps

BACKGROUND & AIMS

Gastrointestinal polyposis is a common clinical problem, yet there is no consensus on how to best manage patients with moderate-load polyposis. Identifying genetic features of this disorder could improve management and especially surveillance of these patients. We sought to determine the prevalence of hamartomatous polyposis-associated mutations in the susceptibility genes PTEN, BMPR1A, SMAD4, ENG, and STK11 in individuals with ≥5 gastrointestinal polyps, including at least 1 hamartomatous or hyperplastic/serrated polyp.

METHODS

We performed a prospective, referral-based study of 603 patients (median age: 51 years; range, 2-89 years) enrolled from June 2006 through January 2012. Genomic DNA was extracted from peripheral lymphocytes and analyzed for specific mutations and large rearrangements in PTEN, BMPR1A, SMAD4, and STK11, as well as mutations in ENG. Recursive partitioning analysis was used to determine cutoffs for continuous variables. The prevalence of mutations was compared using Fisher's exact test. Logistic regression analyses were used to determine univariate and multivariate risk factors.

RESULTS

Of 603 patients, 119 (20%) had a personal history of colorectal cancer and most (n = 461 [76%]) had <30 polyps. Seventy-seven patients (13%) were found to have polyposis-associated mutations, including 11 in ENG (1.8%), 13 in PTEN (2.2%), 13 in STK11 (2.2%), 20 in BMPR1A (3.3%), and 21 in SMAD4 (3.5%). Univariate clinical predictors for risk of having these mutations included age at presentation younger than 40 years (19% vs 10%; P = .008), a polyp burden of ≥30 (19% vs 11%; P = .014), and male sex (16% vs 10%; P = .03). Patients who had ≥1 ganglioneuroma (29% vs 2%; P < .001) or presented with polyps of ≥3 histologic types (20% vs 2%; P = .003) were more likely to have germline mutations in PTEN.

CONCLUSIONS

Age younger than 40 years, male sex, and specific polyp histologies are significantly associated with risk of germline mutations in hamartomatous-polyposis associated genes. These associations could guide clinical decision making and further investigations.

Distinguishing Ménétrier's disease from its mimics

OBJECTIVE

Ménétrier's disease (MD) is a rare hypertrophic gastropathy characterised by giant rugal folds, hypochlorhydria, protein loss and a classic constellation of symptoms (nausea, vomiting, abdominal pain and peripheral oedema). It is considered a clinical diagnosis that may at times be difficult to establish. Firm diagnostic criteria for MD are proposed by delineating the clinicopathological features that best differentiate MD from its mimics.

METHOD

48 patients referred to Vanderbilt University Medical Center for consideration of enrolment in a clinical trial of treatment of patients with MD with cetuximab were evaluated for a definitive diagnosis by assessing the clinical presentation, pertinent laboratory values and histopathological features.

RESULTS

MD was confirmed in 25 of the 48 patients (52%). The remaining 23 patients were considered to be mimics of MD, the most common diagnoses being gastric polyps or polyposis syndromes (13/23, 57%). Gastric slides were available from 40 of the 48 patients for detailed histological analysis (22/25 MD and 18/23 non-MD). Foveolar hyperplasia, glandular tortuosity and dilation, and a marked reduction in parietal cell number were present in all 22 cases of MD. Lamina propria smooth muscle hyperplasia and oedema characterised most cases (18/22 and 19/22, respectively). More than half had prominent eosinophils (11/22) and/or plasma cells (12/22) in the lamina propria. The clinical presentation of patients with MD was characterised by significantly younger age of onset, male predominance and increased vomiting compared with non-MD patients, and a lower prevalence of anaemia compared with MD patients with polyps. There was a trend towards increased frequency of peripheral oedema in patients with MD compared with non-MD patients.

CONCLUSIONS

MD is most accurately diagnosed by clinicohistopathological analysis including oesophagogastroduodenoscopy with gastric pH, appropriate laboratory tests (complete blood count, serum albumin, serum gastrin, Helicobacter pylori and cytomegalovirus serology) and full-thickness mucosal biopsy of the involved gastric mucosa.

Hereditary hamartomatous polyposis syndromes: understanding the disease risks as children reach adulthood

Hamartomatous polyposis syndromes are a rare group of hereditary autosomal dominant disorders that comprise less than 1% of all hereditary colorectal cancers. Hamartomatous polyps, in and of themselves, are benign entities; however, these hamartomatous polyposis syndromes have a malignant potential for the development of colorectal cancer as well as extracolonic cancers. Early detection and proper surveillance are vital to minimizing the risk of carcinoma. This article provides a critical review of the clinical presentation, pathology, genetics, and screening and surveillance guidelines of juvenile polyposis syndrome, PTEN hamartoma tumor syndrome, and Peutz-Jeghers syndrome.

Matrix metalloproteinases in the urine and tissue of patients with juvenile polyps: potential biomarkers for the presence of polyps

BACKGROUND AND AIMS

Juvenile polyps are the most common type of pediatric gastrointestinal polyp and are typically characterized as hamartomatous overgrowths. Juvenile polyps are highly vascularized tissues and display a markedly increased mucosal microcirculation. Matrix metalloproteinases (MMPs) are a family of zinc-dependent enzymes that play an essential role in the physiological degradation of the extracellular matrix in normal development, tumor invasion, and metastasis, as well as angiogenesis. We hypothesized that the presence of these enzymes in urine may serve as clinical biomarkers of juvenile polyps.

PATIENTS AND METHODS

In this preliminary study, we analyzed 32 urine samples collected prospectively from 16 subjects with known or suspected juvenile polyps who presented to the endoscopy unit for colonoscopic evaluation and 16 age- and sex-matched controls. Urinary MMPs were analyzed by zymography and their localized tissue expression was assayed via immunohistochemistry of tissue sections.

RESULTS

MMPs were detected in the urine of patients with juvenile polyps with significantly higher frequency when compared with urine of control subjects. In addition, immunohistochemistry demonstrated that high levels of MMPs were localized in the epithelium and lamina propria of polyp tissue when compared with colonic tissue collected from healthy control subjects.

CONCLUSIONS

These data are the first to demonstrate that MMPs are present in the urine and tissue of patients with juvenile polyps, and these enzymes have the potential to serve as surrogate markers for the presence of polyps.

Juvenile polyposis syndrome

AIM

Report of a series of 12 cases of juvenile polyposis coli.

METHODS

The study period was from 1995 to 2005. All the patients were treated by total colectomy with rectal mucosectomy and endorectal ileoanal pullthrough with or without ileal pouch formation. Covering ileostomy was avoided in all the cases. Time taken for the surgery, postoperative complications and continence were documented.

RESULTS

The mean operating time was 4.2 h (range: 4-5 h). The mean duration of hospital stay was 16.3 days (range: 15-18 days). The most common postoperative complication was pouchitis and perianal excoriation. Initially, all the patients were passing stools at an interval of 2 h, and after 3 weeks, the frequency has reduced to 6-8 stools per day. In the follow-up after 3 months, the frequency was 3-5 per day with minimal soiling.

CONCLUSIONS

Single-stage total colectomy with rectal mucosectomy and endorectal ileoanal pull-through without covering ileostomy and pouch formation is a safe and definitive treatment for juvenile polyposis coli if the patient selection is appropriate.