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Background: Familial adenomatous polyposis (FAP) is an autosomal dominant colorectal tumour syndrome characterised by the formation of multiple adenomatous polyps throughout the colon. It is important to understand the extracolonic phenotype that characterizes FAP. Most previous case reports of patients with both FAP and intellectual disability (ID) have described deletions in all or part of chromosome 5q, including the APC locus. However, it remains unclear whether the ID phenotype in patients with FAP is due to APC disruption or another genetic defect in the deleted 5q region. Case presentation: Patient of family 1 is a 32-year-old woman presented with > 500 colorectal adenomatous polyps, gastric fundic gland polyposis, several duodenal adenomas, and mild intellectual disability (ID). She had no known family history of the FAP phenotype or ID. By copy number trio analysis, a 15.4 Mb interstitial heterozygous de novo deletion including APC region was observed in 5q21.2. q22.3. The patient in family 2 was a 29-year-old man with approximately 50 colorectal adenomatous polyps, fundic gland polyposis in the stomach, non-ampullary adenomas in the duodenum, and mild ID. He had no family history of the FAP phenotype or ID. Using copy number trio analysis, a de novo 9.8 Mb heterozygous deletion was identified on 5q22.1. q23.1 which includes the APC region. Conclusions: Based on previous reports and the present study, we narrowed down the 5p deletion region associated with ID in FAP. Further investigation is required to understand ID due to 5q stromal deletion. [ABSTRACT FROM AUTHOR]

Abstract Background Familial adenomatous polyposis (FAP) is an autosomal dominant colorectal tumour syndrome characterised by the formation of multiple adenomatous polyps throughout the colon. It is important to understand the extracolonic phenotype that characterizes FAP. Most previous case reports of patients with both FAP and intellectual disability (ID) have described deletions in all or part of chromosome 5q, including the APC locus. However, it remains unclear whether the ID phenotype in patients with FAP is due to APC disruption or another genetic defect in the deleted 5q region. Case presentation Patient of family 1 is a 32-year-old woman presented with > 500 colorectal adenomatous polyps, gastric fundic gland polyposis, several duodenal adenomas, and mild intellectual disability (ID). She had no known family history of the FAP phenotype or ID. By copy number trio analysis, a 15.4 Mb interstitial heterozygous de novo deletion including APC region was observed in 5q21.2. q22.3. The patient in family 2 was a 29-year-old man with approximately 50 colorectal adenomatous polyps, fundic gland polyposis in the stomach, non-ampullary adenomas in the duodenum, and mild ID. He had no family history of the FAP phenotype or ID. Using copy number trio analysis, a de novo 9.8 Mb heterozygous deletion was identified on 5q22.1. q23.1 which includes the APC region. Conclusions Based on previous reports and the present study, we narrowed down the 5p deletion region associated with ID in FAP. Further investigation is required to understand ID due to 5q stromal deletion.

Simple Summary: Myelodysplastic syndromes with isolated del(5q) constitute the only MDS subtype defined by a cytogenetic alteration. The results of several clinical studies and the advances in new technologies have provided a better understanding of the biological basis of this disease. Specific genetic alterations have been found to be associated with prognosis and response to treatments. This review intends to summarize the current knowledge of the molecular background of MDS with isolated del(5q), focusing on the clinical and prognostic relevance of cytogenetic alterations and somatic mutations. Myelodysplastic syndromes (MDS) are a group of clonal hematological neoplasms characterized by ineffective hematopoiesis in one or more bone marrow cell lineages. Consequently, patients present with variable degrees of cytopenia and dysplasia. These characteristics constitute the basis for the World Health Organization (WHO) classification criteria of MDS, among other parameters, for the current prognostic scoring system. Although nearly half of newly diagnosed patients present a cytogenetic alteration, and almost 90% of them harbor at least one somatic mutation, MDS with isolated del(5q) constitutes the only subtype clearly defined by a cytogenetic alteration. The results of several clinical studies and the advances of new technologies have allowed a better understanding of the biological basis of this disease. Therefore, since the first report of the "5q- syndrome" in 1974, changes and refinements have been made in the definition and the characteristics of the patients with MDS and del(5q). Moreover, specific genetic alterations have been found to be associated with the prognosis and response to treatments. The aim of this review is to summarize the current knowledge of the molecular background of MDS with isolated del(5q), focusing on the clinical and prognostic relevance of cytogenetic alterations and somatic mutations. [ABSTRACT FROM AUTHOR]

PI-PLCβ1 is involved in cell proliferation, differentiation, and myelodysplastic syndrome (MDS) pathogenesis. Moreover, the increased activity of PI-PLCβ1 reduces the expression of PKC-α, which, in turn, delays the cell proliferation and is linked to erythropoiesis. Lenalidomide is currently used in low-risk patients with MDS and del(5q), where it can suppress the del(5q) clone and restore normal erythropoiesis. In this study, we analyzed the effect of lenalidomide on 16 patients with low-risk del(5q) MDS, as well as del(5q) and non-del(5q) hematopoietic cell lines, mainly focusing on erythropoiesis, cell cycle, and PI-PLCβ1/PKC-α signaling. Overall, 11 patients were evaluated clinically, and 10 (90%) had favorable responses; the remaining case had a stable disease. At a molecular level, both responder patients and del(5q) cells showed a specific induction of erythropoiesis, with a reduced γ/β-globin ratio, an increase in glycophorin A, and a nuclear translocation of PKC-α. Moreover, lenalidomide could induce a selective G0/G1 arrest of the cell cycle in del(5q) cells, slowing down the rate proliferation in those cells. Altogether, our results could not only better explain the role of PI-PLCβ1/PKC-α signaling in erythropoiesis but also lead to a better comprehension of the lenalidomide effect on del(5q) MDS and pave the way to innovative, targeted therapies. [ABSTRACT FROM AUTHOR]

The long-term hematological response in a patient with 5q- syndrome after lenalidomide suspension and the further improvement observe while she was receiving deferasirox alone is reported.

Abstract: Lenalidomide is known to be effective in myelodysplastic syndromes (MDS) with del(5q) in improving anemia and suppressing del(5q) cells. MDS with del(5q) shows increase of nonlobulated megakaryocytes. However, histopathology of MDS with del(5q) treated with lenalidomide has not been fully studied. We investigated the morphologic changes in lenalidomide treated low- or intermediate-1-risk MDS with del(5q). All of evaluable patients showed high proportion of nonlobulated megakaryocytes. The nonlobulated megakaryocytes were markedly decreased in 6 patients during therapy in parallel with suppression of del(5q) cells. Our analysis suggests that single allele deletion of common deleted region inhibits nuclear lobulation of megakaryocytes. [Copyright &y& Elsevier]

Lenalidomide is an immunomodulatory agent recently reported to be effective in the treatment of transfusion-dependent anemia due to low- or intermediate-1 risk myelodysplastic syndromes (MDS) associated with a deletion 5q (del 5q) cytogenetic abnormality. We conducted a multicenter, single-arm clinical trial to evaluate the safety and efficacy of lenalidomide in Japanese patients with anemia in low- or intermediate-1 risk MDS associated with the del 5q cytogenetic abnormality. Eleven patients (5 with transfusion-dependent anemia; 6 with transfusion-independent symptomatic anemia) received once daily oral administrations of 10 mg of lenalidomide for 21 consecutive days in a 28-day treatment cycle. The efficacy was assessed by the IWG criteria. At an interim analysis after > or =24 weeks of therapy, hemoglobin increase was noted in all 11 patients, with a median increase of 6.0 g/dL (range, 0.9-10.9) from the baseline. All transfusion-dependent patients achieved transfusion independence. Histopathologic and cytogenetic improvement was also noted. Neutropenia and thrombocytopenia were the most common adverse events related to lenalidomide. The adverse events were manageable, and no patients experienced serious adverse events or adverse events requiring treatment discontinuation. The results indicate that lenalidomide can be a useful agent for treating Japanese patients with anemia associated with low- or intermediate-1 risk MDS with the del 5q cytogenetic abnormality. [ABSTRACT FROM AUTHOR]