Genetic Heterogeneity in Cellular Angiofibromas.

BACKGROUND: Cellular angiofibroma, a rare benign mesenchymal neoplasm, is classified within the 13q/RB1 family of tumors due to morphological, immunohistochemical, and genetic similarities with spindle cell lipoma. Here, genetic data reveal pathogenetic heterogeneity in cellular angiofibroma. METHODS: Three cellular angiofibromas were studied using G-banding/Karyotyping, array comparative genomic hybridization, RNA sequencing, and direct cycling sequencing. RESULTS: The first tumor carried a del(13)(q12) together with heterozygous loss and minimal expression of the RB1 gene. Tumors two and three displayed chromosome 8 abnormalities associated with chimeras of the pleomorphic adenoma gene 1 (PLAG1). In tumor 2, the cathepsin B (CTSB) fused to PLAG1 (CTSB::PLAG1) while in tumor 3, the mir-99a-let-7c cluster host gene (MIR99AHG) fused to PLAG1 (MIR99AHG::PLAG1), both leading to elevated expression of PLAG1 and insulin growth factor 2. CONCLUSION: This study uncovers two genetic pathways contributing to the pathogenetic heterogeneity within cellular angiofibromas. The first aligns with the 13q/RB1 family of tumors and the second involves PLAG1-chimeras. These findings highlight the diverse genetic landscape of cellular angiofibromas, providing insights into potential diagnostic strategies.

Trends in the survival of patients with trisomy 13 from 1995 to 2021: A population study in Japan.

It remains unclear whether recent changes in the prognosis and management of patients with trisomy 13 impact patient survival. We investigated changes in survival of patients with trisomy 13 in Japan. Data from the Vital Statistics Database in Japan was retrieved to examine the association of sex, surgical history, and years of birth and death with changes in survival patterns in 1164 patients with trisomy 13 between 1995 and 2021. The rates of deaths due to trisomy 13 increased from 9.8% to 23.1% in those over 1 year of age and from 7.3% to 19.2% in those within 24 h of birth between 1995 and 2021. The median survival time was longer in 2009-2021 than in 1996-2008 (40 vs. 84 days, p < 0.001). The median survival time and the rate of patients with surgical history increased from 91 days and 16.0% in 1996-2008 to 179 days and 28.0% in 2009-2021, respectively. Median survival time among patients with trisomy 13 has increased over the last 26 years, with almost 1 in 3 patients currently surviving for more than 1 year. The increased surgical intervention rate might have contributed to this improvement.

Specific Deletions of Chromosomes 3p, 5q, 13q, and 21q among Patients with G2 Grade of Non-Small Cell Lung Cancer.

Non-small cell lung cancer (NSCLC) leads as a primary cause of cancer-related premature mortality in Western populations. This study leverages cutting-edge gene-expression-profiling technologies to perform an in-depth molecular characterization of NSCLC specimens, with the objective of uncovering tumor-specific genomic alterations. By employing DNA microarray analysis, our research aims to refine the classification of NSCLC for early detection, guide molecular-targeted treatment approaches, enhance prognostication, and broaden the scientific understanding of the disease's biology. We identified widespread genomic abnormalities in our samples, including the recurrent loss of chromosomal regions 3p, 5q, 13q, and 21q and the gain of 12p. Furthermore, utilizing Metascape for bioinformatic analysis revealed critical biological pathways disrupted in NSCLC, offering promising leads for novel therapeutic interventions.

miR-15a/16-1 deletion in activated B cells promotes plasma cell and mature B-cell neoplasms.

Chromosome 13q deletion [del(13q)], harboring the miR-15a/16-1 cluster, is one of the most common genetic alterations in mature B-cell malignancies, which originate from germinal center (GC) and post-GC B cells. Moreover, miR-15a/16 expression is frequently reduced in lymphoma and multiple myeloma (MM) cells without del(13q), suggesting important tumor-suppressor activity. However, the role of miR-15a/16-1 in B-cell activation and initiation of mature B-cell neoplasms remains to be determined. We show that conditional deletion of the miR-15a/16-1 cluster in murine GC B cells induces moderate but widespread molecular and functional changes including an increased number of GC B cells, percentage of dark zone B cells, and maturation into plasma cells. With time, this leads to development of mature B-cell neoplasms resembling human extramedullary plasmacytoma (EP) as well as follicular and diffuse large B-cell lymphomas. The indolent nature and lack of bone marrow involvement of EP in our murine model resembles human primary EP rather than MM that has progressed to extramedullary disease. We corroborate human primary EP having low levels of miR-15a/16 expression, with del(13q) being the most common genetic loss. Additionally, we show that, although the mutational profile of human EP is similar to MM, there are some exceptions such as the low frequency of hyperdiploidy in EP, which could account for different disease presentation. Taken together, our studies highlight the significant role of the miR-15a/16-1 cluster in the regulation of the GC reaction and its fundamental context-dependent tumor-suppression function in plasma cell and B-cell malignancies.

[Prenatal genetic diagnosis of a case with ring chromosome 13].

OBJECTIVE: To carry out cyto- and molecular genetic analysis for a fetus with a ring chromosome identified through non-invasive prenatal testing (NIPT). METHODS: A pregnant woman presented at the Shengjing Hospital Affiliated to China Medical University on May 11, 2021 was selected as the study subject. Maternal peripheral blood sample was screened by NIPT, and G-banded chromosomal karyotyping was carried out on amniotic fluid and peripheral blood samples from the couple. The fetus and the pregnant woman were also subjected to genomic copy number variation sequencing (CNV-seq), chromosomal microarray analysis (CMA), and fluorescence in situ hybridization (FISH) assay. RESULTS: NIPT result suggested that the fetus had monomeric mosaicism or fragment deletion on chromosome 13. G banded chromosomal analysis showed that both the fetus and its mother had a karyotype of 47,XX,der(13)(pter→p11::q22→q10),+r(13)(::p10::q22→qter::), whilst her husband had a normal karyotype. FISH has verified the above results. No abnormality was detected with CNV-seq and CMA in both the fetus and the pregnant woman. CONCLUSION: The ring chromosome 13 in the fetus has derived from its mother without any deletion, duplication and mosaicism. Both the fetus and the pregnant woman were phenotypically normal.

13q12.2 deletions in acute lymphoblastic leukemia lead to upregulation of FLT3 through enhancer hijacking.

Mutations in the FMS-like tyrosine kinase 3 (FLT3) gene in 13q12.2 are among the most common driver events in acute leukemia, leading to increased cell proliferation and survival through activation of the phosphatidylinositol 3-kinase/AKT-, RAS/MAPK-, and STAT5-signaling pathways. In this study, we examine the pathogenetic impact of somatic hemizygous 13q12.2 microdeletions in B-cell precursor (BCP) acute lymphoblastic leukemia (ALL) using 5 different patient cohorts (in total including 1418 cases). The 13q12.2 deletions occur immediately 5' of FLT3 and involve the PAN3 locus. By detailed analysis of the 13q12.2 segment, we show that the deletions lead to loss of a topologically associating domain border and an enhancer of FLT3. This results in increased cis interactions between the FLT3 promoter and another enhancer located distally to the deletion breakpoints, with subsequent allele-specific upregulation of FLT3 expression, expected to lead to ligand-independent activation of the receptor and downstream signaling. The 13q12.2 deletions are highly enriched in the high-hyperdiploid BCP ALL subtype (frequency 3.9% vs 0.5% in other BCP ALL) and in cases that subsequently relapsed. Taken together, our study describes a novel mechanism of FLT3 involvement in leukemogenesis by upregulation via chromatin remodeling and enhancer hijacking. These data further emphasize the role of FLT3 as a driver gene in BCP ALL.

High-grade glioma with pleomorphic and pseudopapillary features (HPAP): a proposed type of circumscribed glioma in adults harboring frequent TP53 mutations and recurrent monosomy 13.

Tumors of the central nervous system (CNS) often display a wide morphologic spectrum that has, until recently, been the sole basis for tumor classification. The introduction of the integrated histomolecular diagnostic approach in CNS tumors has facilitated a classification system that is increasingly data-driven and with improved alignment to clinical outcome. Here, we report a previously uncharacterized glioma type (n = 31) using unsupervised clustering analysis of DNA methylation array data from approximately 14,000 CNS tumor samples. Histologic examination revealed circumscribed growth and morphologic similarities to pleomorphic xanthoastrocytoma (PXA), astroblastoma, ependymoma, polymorphous neuroepithelial tumor of the young (PLNTY), and IDH-wildtype glioblastoma (GBM). Median age (46.5 years) was significantly older than other circumscribed gliomas and younger than GBM. Dimensionality reduction with uniform manifold approximation and projection (UMAP) and hierarchical clustering confirmed a methylation signature distinct from known tumor types and methylation classes. DNA sequencing revealed recurrent mutations in TP53 (57%), RB1 (26%), NF1 (26%), and NF2 (14%). BRAF V600E mutations were detected in 3/27 sequenced cases (12%). Copy number analysis showed increased whole chromosome aneuploidy with recurrent loss of chromosome 13 (28/31 cases, 90%). CDKN2A/B deletion (2/31, 6%) and MGMT promoter methylation (1/31, 3%) were notably rare events. Most tumors showed features of a high-grade glioma, yet survival data showed significantly better overall survival compared to GBM (p < 0.0001). In summary, we describe a previously uncharacterized glioma of adults identified by a distinct DNA methylation signature and recurrent loss of chromosome 13.

Severe recalcitrant hidradenitis suppurativa in a 2-year-old boy with partial trisomy 13.

We report the case of a 2-year-old boy with mosaic trisomy 13 and immunodeficiency who developed severe hidradenitis suppurativa beginning at the age of 18 months. Unresponsive to standard therapies, he exhibited a partial response to immunoglobulin replacement therapy.

Cytogenetic and molecular characterization of a patient having infertility and mild intellectual disability with a very rare unstable ring chromosome 13.

INTRODUCTION: Ring chromosomes arise from breakage and fusion at distal regions of short and long arms of the chromosomes. The effect of the ring chromosome on the phenotype may vary widely depending on the amount of the deletion in the chromosomal areas and genes implicated in these regions. CASE PRESENTATION: We present a 35-year-old male patient with infertility and mild intellectual disability (MID) who has de novo ring 13 (r(13)) chromosomes. To determine chromosomal abnormality, we performed karyotype analysis, Y chromosome microdeletion analysis, FISH, and aCGH techniques. CONCLUSION: The patient's karyotype analysis result was mos46,XY,r(13)(p13q34)[75]/45,XY,-13[14]/46,XY,dic (13;13)[8]/47,XY,r(13), + r(13)[2]/46,XY,tetrac r(13;13;13;13)[1]. FISH analysis supported the findings of the cytogenetic analysis. Y microdeletion analysis showed that the AZF region was intact. On aCGH analysis, we detected a 1.5 megabase deletion at the end of chromosome 13, including the CHAMP1 gene. The loss of the CHAMP1 gene, in particular, may explain our patient's MID, and the other deleted genes at 13q34 may explain our patient's infertility.

Dinosaur Tail Appendix in Trisomy 13.

BackgroundAmong the many malformations associated with trisomy 13, one of the less recognized is dinosaur tail appendix. Case report: We illustrate a dinosaur-tail appendix from an autopsy in a newborn female with trisomy 13. This malformation has a frequency between 0.014% and 3.7% in general population. Conclusion: Trisomy 13 is a relatively well-known chromosomal disorder in which dinosaur tail appendix can be found. This entity should be considered element of a complete morphological diagnosis.

Karyotype patterns, clinical features, and parental ages of three predominant live born autosomal trisomies of Northeast Malaysia.

Chromosomal abnormality is one of the causes of congenital disorders among newborns. Despite aneuploidy being the major cause of first trimester miscarriages, very few aneuploidies such as trisomies of chromosomes 13, 18 and 21 survive to birth. The results of 4,064 patients referred for cytogenetic analysis at Human Genome Centre, Universiti Sains Malaysia, Kelantan, Malaysia between 2008 and 2019 were reviewed. We retrospectively investigated the karyotype patterns, clinical features and parental ages of the three common live-born autosomal trisomies such as trisomy 13, trisomy 18 and trisomy 21. The relative frequency of cases with the total sample received and cultured was calculated in each group and compared with those reported elsewhere. Between 2008 and 2019, a total of 1034 live-born trisomic cases which accounted for 25.4% of the 4064 total referred cases and 73.7% of 1403 suspected trisomy cases, were identified, with age ranging from newborns to 57 years. Down syndrome was the commonest aneuploidy (857 cases; 21.1%) followed by Edwards syndrome (133 cases; 3.3%) and Patau syndrome (44 cases; 1.1%). The number of diagnosed cases for each of the trisomies was fairly stable from year to year. About two-thirds of both maternal and paternal ages were ≥ 35 years. This is the first cytogenetic report on the common live-born autosomal trisomies in the North-Eastern region of Malaysia. The prevalence of trisomies 21 was found to be higher compared to an earlier study in the North-Western region of Malaysia, wherein also, advanced maternal age was a significant risk factor.

Molecular mechanism for the multiple sclerosis risk variant rs17594362.

Multiple sclerosis (MS) is known as an autoimmune demyelinating disease of the central nervous system. However, its cause remains elusive. Given previous studies suggesting that dysfunctional oligodendrocytes (OLs) may trigger MS, we tested whether single nucleotide polymorphisms (SNPs) associated with MS affect OL enhancers, potentially increasing MS risk by dysregulating gene expression of OL lineage cells. We found that two closely spaced OL enhancers, which are 3 Kb apart on chromosome 13, overlap two MS SNPs in linkage disequilibrium-rs17594362 and rs12429256. Our data revealed that the two MS SNPs significantly up-regulate the associated OL enhancers, which we have named as Rgcc-E1 and Rgcc-E2. Analysis of Hi-C data and epigenome editing experiments shows that Rgcc is the primary target of Rgcc-E1 and Rgcc-E2. Collectively, these data indicate that the molecular mechanism of rs17594362 and rs12429256 is to induce Rgcc overexpression by potentiating the enhancer activity of Rgcc-E1 and Rgcc-E2. Importantly, the dosage of the rs17594362/rs12429256 risk allele is positively correlated with the expression level of Rgcc in the human population, confirming our molecular mechanism. Our study also suggests that Rgcc overexpression in OL lineage cells may be a key cellular mechanism of rs17594362 and rs12429256 for MS.

Multiregional sequencing and circulating tumour DNA analysis provide complementary approaches for comprehensive disease profiling of small lymphocytic lymphoma.

We aimed at molecularly dissecting the anatomical heterogeneity of small lymphocytic lymphoma (SLL), by analysing a cohort of 12 patients for whom paired DNA from a lymph node biopsy and circulating cells, as well as plasma-circulating tumour DNA (ctDNA) was available. Notably, the analyses of the lymph node biopsy and of circulating cells complement each other since a fraction of mutations (20·4% and 36·4%, respectively) are unique to each compartment. Plasma ctDNA identified two additional unique mutations. Consistently, the different synchronous sources of tumour DNA complement each other in informing on driver gene mutations in SLL harbouring potential prognostic and/or predictive value.

Identification of Chromosome 17 Trisomy in a Cynomolgus Monkey (Macaca fascicularis) by Multicolor FISH Techniques.

A female cynomolgus monkey (Macaca fascicularis) with facial features characteristic of Down syndrome showed abnormal behavior, unwariness toward humans, and poor concentration. The number of metaphase chromosomes in blood lymphocytes was examined and found to be 43, which indicated one extra chromosome to the normal diploid number (2n = 42). We then used Q-banding and multicolor FISH techniques to identify the extra chromosome. The results revealed an additional chromosome 17, with no other chromosomal rearrangements, such as translocations. Since no mosaicism or heterozygous variant chromosomes were observed, full trisomy 17 was assessed in this female cynomolgus monkey. Chromosome 17 corresponds to human chromosome 13, and human trisomy 13, known as Patau syndrome, results in severe clinical signs and, often, a short life span; however, this individual has reached an age of 10 years with only mild clinical signs. Although genomic differences exist between human and macaques, this individual's case could help to reveal the pathological and genetic mechanisms of Patau syndrome.

An Anomaly with Potential as a New Prognostic Marker in CLL with del(13q): Gain of 16p13.3.

Deletion 13q [del(13q)] is a favorable prognostic marker if it is detected as a sole abnormality in chronic lymphocytic leukemia (CLL). However the clinical courses of cases with isolated del(13q) are quite heterogeneous. In our study, we investigated copy number variations (CNVs), loss of heterozygosity (LOH), and the size of del(13q) in 30 CLL patients with isolated del(13q). We used CGH+SNP microarrays in order to understand the cause of this clinical heterogeneity. We detected del(13q) in 28/30 CLL cases. The size of the deletion varied from 0.34 to 28.81 Mb, and there was no clinical effect of the deletion size. We found new prognostic markers, especially the gain of 16p13.3. These markers have statistically significant associations with short time to first treatment and advanced disease stage. Detecting both CNVs and LOH at the same time is an advantageous feature of aCGH+SNP. However, it is very challenging for the array analysis to detect mosaic anomalies. Therefore, it is very important to confirm the results by FISH. In our study, we detected approximately 9% mosaic del(13q) by microarray. In addition, the gain of 16p13.3 may affect the disease prognosis in CLL. However, additional studies with more patients are needed to confirm these results.

Parent-reported histories of adults with trisomy 13 syndrome.

Clinical histories and outcome data of long-term survivors with trisomy 13 are rare. The goal of this study was to collect the medical histories of adult individuals (≥18 years old) with apparent non-mosaic trisomy 13/Patau syndrome to help gain further insight in to the clinical course for individuals with this condition and to characterize the manifestations for surveillance and management. We collected 11 families through a contact person with the LWT13 (Living with Trisomy 13) LIFE support group. We performed telephone interviews to gather their medical histories and report these data in system-based summaries, tables, and clinical vignettes. In instances where parents retained copies of genetic testing reports or clinicians currently taking care of the individual with trisomy 13 were able to provide documentation, we confirmed diagnosis. All clinical histories and reported manifestations were consistent with a diagnosis of trisomy 13. We also elicited comments from parents on their personal experiences of raising an individual with trisomy 13.

Lessons from a 30 year follow-up of monozygotic twins with discordant phenotype due to a ring 13 chromosomal mosaicism in one of them.

At the 43rd annual meeting of the ASHG in 1993, the senior author reported monozygotic twins with discordant phenotype due to a ring 13 chromosomal mosaic syndrome in one of them. Her major manifestations included: intrauterine growth restriction (IUGR), failure to thrive (FTT), delayed developmental milestones/intellectual disability (DDM/ID), left hemihypoplasia of her body with leg length discrepancy, left profound deafness due to inner ear malformation, telecanthus, dental anomalies mainly on the left side, congenital torticollis due to Klippel-Feil anomaly, 13 ribs, scoliosis, dislocation of the left hip, and distinctive left hand and feet. A blood karyotype at age 31/2 was normal. Silver-Russell syndrome was initially suspected; however, at age 4, a karyotype on skin fibroblasts showed a ring 13 chromosomal mosaicism, 46,XX,15s+/46,XX,-13,+r(13),15s+, with a higher frequency on the left side of the body. Since then, we have been involved in the management of this patient for 30 years. This has ultimately allowed us to compare her achievements with her normal monozygotic twin. In this long term follow-up, we want to emphasize the importance of: (a) early recognition of genetic syndromes, especially of mosaicisms, and of early intervention programs, (b) the involvement of different specialists in the management of patients with MCA, and (c) mentioning how familial and socioeconomic issues may limit or enhance the full potential of patients with some genetic disorders.

Feingold syndrome type 2 in a patient from China.

Feingold syndrome type 2 (FGLDS2, MIM614326) is a genetic congenital malformation syndrome, caused by germline heterozygous deletion of MIR17HG on chromosome 13q31, which is extremely rare worldwide. To date, less than 25 patients have been described in the literature. Here, we report on a 3-year-old girl presented with hip dysplasia, polysyndactyly of the left thumb, brachymesophalangy of the fifth digit, microcephaly, intellectual disability, and growth delay. This is likely to be the first case of Feingold syndrome type 2 ever discovered among Chinese population. Through genetic testing and pedigree analysis, she was identified to have a de novo 4.8-Mb microdeletion at chromosome 13q31.3-q32.1, encompassing MIR17HG, GPC5, and GPC6. Additionally, we detected two common compound heterozygous variants (c.919-2A>G and c.147C>G) in SLC26A4 encoding pendrin protein, as well as a novel heterozygous variant c.985_988del in COMP encoding cartilage oligomeric matrix protein. This case report aims to analyze the microdeletion and the three types of variant detected in the patient, and to explore the association between the genotype and phenotype in patients with Feingold syndrome type 2, which may contribute to further understanding and future diagnosis of this disorder.

Genetic variability in 13q33 and 9q34 is linked to aggressiveness patterns and a higher risk of progression of non-muscle-invasive bladder cancer at the time of diagnosis.

OBJECTIVE: To identify single nucleotide polymorphisms (SNPs) associated with patterns of aggressiveness of non-muscle-invasive bladder cancer (NMIBC). PATIENTS AND METHODS: From January 2011 to December 2018, 476 patients with NMIBC were prospectively included. The first step aimed to identify SNPs associated with aggressiveness patterns (e.g. ≥pT1or high-grade/Grade 3 or presence of carcinoma in situ) by analysing the data of a genome-wide association study (GWAS) on 165 patients with BC. The second step aimed to validate the SNPs previously identified, by genotyping the germline DNA of 311 patients with NMIBC. RESULTS: Overall, the median (interquartile range) age was 66 (58-75) years and the rate of patients with aggressive NMIBC was comparable between both groups (46% vs 46%, P = 1). GWAS data analysis identified four SNPs associated with an aggressive NMIBC (rs12615669, rs4976845, rs2989734, and rs2802288). In the validation cohort, the genotype CC of rs12615669, as well as age >70 years at the time of diagnosis were associated with aggressive NMIBC (P = 0.008 and P < 0.001, respectively). Genotyping of the entire cohort showed an association between aggressive NMIBC and the T allele of rs12615669 (P = 0.0007), the A allele of rs4976845 (P = 0.012), and the A allele of rs2989734 (P = 0.007). A significant association was also found for the entire cohort between the risk of progression and the A allele of rs4976845 (P = 0.04). CONCLUSION: This two-phase study identified three SNPs (rs12615669, rs4976845, and rs2989734) associated with aggressive NMIBC and one SNP (rs4976845) associated with a higher risk of progression.

Retinoblastoma management in 13q deletion syndrome patients using super-selective chemotherapies and other cancer-directed interventions.

BACKGROUND: This study aimed to identify best practices for treating 13q deletion syndrome (13q-) patients with retinoblastoma in the era of super-selective ophthalmic artery chemosurgery (OAC) and intravitreal injection therapy (IVIT). METHODS: Retrospective study of 21 eyes from 14 patients with retinoblastoma and 13q- who were treated at Memorial Sloan Kettering Cancer Center (MSKCC) between May 2006 and May 2020, with a mean follow up of 3.7 years. Ocular survival, patient survival, and treatment toxicities were assessed. RESULTS: Nine of the 12 eyes that underwent OAC/IVIT at MSKCC have been progression free for at least 1 year since their last treatments. Fifteen out of 26 OAC cycles resulted in grade 3-4 hematologic toxicity. There was one death from sepsis in the setting of intravenous chemotherapy (IVC) for metastatic disease that occurred after OAC/IVIT therapy. The 2-year Kaplan-Meier ocular survival estimate for the whole cohort was 75% and for the eyes that received OAC or IVIT at MSKCC 83%. For OAC hematologic toxicities, one platelet transfusion and two filgrastim doses were administered, and one patient was hospitalized for neutropenic fevers. CONCLUSIONS: The majority of 13q- eyes treated with OAC/IVIT-based regimens can be cured, and there were no deaths related to complications from OAC or IVIT. 13q- Patients did have increased risk of systemic treatment complications, even from super-selective chemotherapies. Despite these toxicities, only one patient developed febrile neutropenia, one patient required a blood product transfusion, and two patients received filgrastim for both OAC and IVC complications. PRÉCIS: Children with 13q deletion syndrome with retinoblastoma managed with intra-arterial and intravitreal chemotherapy have excellent patient and ocular survival with acceptable toxicity.