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2,700 result(s) for "Chromosome 7"
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Distribution of EGFR amplification, combined chromosome 7 gain and chromosome 10 loss, and TERT promoter mutation in brain tumors and their potential for the reclassification of IDHwt astrocytoma to glioblastoma
EGFR amplification ( EGFR amp), the combination of gain of chromosome 7 and loss of chromosome 10 (7+/10−), and TERT promoter mutation (p TERT mut) are alterations frequently observed in adult IDH -wild-type ( IDH wt) glioblastoma (GBM). In the absence of endothelial proliferation and/or necrosis, these alterations currently are considered to serve as a surrogate for upgrading IDH wt diffuse or anaplastic astrocytoma to GBM. Here, we set out to determine the distribution of EGFR amp, 7+/10−, and p TERT mut by analyzing high-resolution copy-number profiles and next-generation sequencing data of primary brain tumors. In addition, we addressed the question whether combinations of partial gains on chromosome 7 and partial losses on chromosome 10 exhibited a diagnostic and prognostic value similar to that of complete 7+/10−. Several such combinations proved relevant and were combined as the 7/10 signature. Our results demonstrate that EGFR amp and the 7/10 signature are closely associated with IDH wt GBM. In contrast, p TERT mut is less specific for IDH wt GBM. We conclude that, in the absence of endothelial proliferation and/or necrosis, the detection of EGFR amp is a very strong surrogate marker for the diagnosis of GBM in IDH wt diffuse astrocytic tumors. The 7/10 signature is also a strong surrogate marker. However, care should be taken to exclude pleomorphic xanthoastrocytoma. p TERT mut is less restricted to this entity and needs companion analysis by other molecular markers to serve as a surrogate for diagnosing IDH wt GBM. A combination of any two of EGFR amp, the 7/10 signature and p TERT mut, is highly specific for IDH wt GBM and the combination of all three alterations is frequent and exclusively seen in IDH wt GBM.
Maternal uniparental disomy of chromosome 7: how chromosome 7-encoded imprinted genes contribute to the Silver–Russell phenotype
Background Silver–Russell syndrome (SRS) is a rare congenital growth disorder which is associated with molecular alterations affecting imprinted regions on chromosome 11p15 and maternal uniparental disomy of chromosome 7 (upd(7)mat). In 11p15, imprinted regions contributing to the SRS phenotype could be identified, whereas on chromosome 7 at least two regions in 7q32 and 7p13 are in discussion as SRS candidate regions. We report on DNA and RNA data from upd(7)mat patients and a monozygotic twin pair with a postnatal SRS phenotype carrying a small intragenic deletion within GRB10 to delineate the contribution of upd(7)mat and imprinted genes on this chromosome to the SRS phenotype. Results Genome sequencing in the monozygotic twins revealed a 18 kb deletion within the paternal allele of the GRB10 gene. Expression of GRB10 in blood of the twins as well as in cells from upd(7)mat and upd(7q)mat patients was not altered, whereas RNAseq indicates noticeable changes of the expression of other genes encoded by chromosomes 7 and other genomic regions. Conclusions Our data indicate that intrauterine growth restriction as the prenatal phenotype of upd(7)mat is caused by defective paternal alleles of the 7q32 region, as well as by overexpression of the maternal GRB10 allele whereas a defective GRB10 paternal allele does not cause this feature. The altered expression of MEST in 7q32 by upd(7)mat is associated with the complete SRS phenotype, whereas maternalization or deletion of the paternal GRB10 copy and duplication of the chromosomal region 7p12 are associated with a postnatal SRS-like phenotype.
PEG10 loss of function causes Silver-Russell syndrome: a familial case with paternal deletion
Silver-Russell syndrome (SRS, MIM#180860) is an imprinting disorder characterized by prenatal and postnatal growth retardation, relative macrocephaly at birth, prominent forehead, feeding difficulties, and body asymmetry. Clinical diagnosis is based on at least 4 out of 6 clinical signs (Netchine-Harbison clinical scoring system). The main molecular mechanisms are loss of methylation at the paternal H19/IGF2:IG-DMR (30-60%) at the 11p15 chromosomal region and maternal uniparental disomy of chromosome 7 (5-10%). While it is well known that deregulation of 11p15 imprinted genes ( IGF2 , H19, and CDKN1C ) contributes to the SRS phenotype, those on chromosome 7 ( GRB10 , PEG10 , and MEST ) are still in discussion. We report two brothers clinically diagnosed with SRS (postnatal growth delay, relative macrocephaly at birth, feeding difficulties, and SRS facies). One patient also has distal tremors and a treated growth hormone deficiency. CGH-array revealed a deletion of 109 Kb including PEG10 and SGCE genes, inherited from their unaffected father. Whole Exome Sequencing did not disclose other causative variants. PEG10 functions as a transcriptional repressor of cyclin-dependent kinase inhibitors, including CDKN1C , for which maternal gain-of-function variants are linked to SRS. Real-time PCR studies showed a downregulation of PEG10 and an upregulation of CDKN1C expression only in the affected brothers. Interestingly, IGF2 was upregulated in the patient 1 under GH administration. Our findings provide the first evidence supporting the role of PEG10 in the pathogenesis of Silver-Russell Syndrome, mediated by a gain-of-function effect on the CDKN1C expression, offering new insights into the molecular mechanisms underlying this condition.
Revertant somatic mosaicism as a cause of cancer
Revertant (somatic) mosaicism is a spontaneous correction of a causative mutation in patients with congenital diseases. A relatively frequent event, revertant mosaicism may bring favorable outcomes that ameliorate disorders, and is therefore called “natural gene therapy.” However, it has been revealed recently that “overcorrection” of inherited bone marrow failure in patients with sterile alpha motif domain containing 9 (SAMD9)/9L syndromes by revertant mosaicism induces myelodysplastic syndrome (MDS) with monosomy 7 that occasionally proceeds to acute myelogenous leukemia (AML). In this review, we interpret very complex mechanisms underlying MDS/AML in patients with SAMD9/9L syndromes. This includes multiple myeloid tumor suppressors on the long arm of chromosome 7, all of which act in a haploinsufficient fashion, and a difference in sensitivity to interferon between cells carrying a mutation and revertants. Overcorrection of mutants by somatic mosaicism is likely a novel mechanism in carcinogenesis. A scheme of myelodysplastic syndrome (MDS) carrying ‐7/del(7q). In patients with SAMD9/9L syndromes, bone marrow cells with SAMD9/9L+/− (revertants) show a high sensitivity to growth factors and a low sensitivity to (the suppressive effects of) interferon (IFN). In addition, surrounding bone marrow cells (SAMD9/9L+/mut) have a high sensitivity to IFN. As a result, the rapid expansion of a ‐7/del(7q) clone causes an “overcorrection,” leading to MDS. This mechanism would be partially applied to sporadic MDS patients with ‐7/del(7q) in old age.
l-asparaginase as an efficient salvage therapy for refractory acute myeloid leukemia with chromosome 7 abnormalities: a case series
Acute myeloid leukemia (AML) with chromosome 7 abnormalities has a dismal prognosis due to a poor complete remission (CR) rate after induction chemotherapy. Although various salvage therapies for refractory AML have been developed for adults, few salvage therapies are available for children. Here, we report the cases of three patients with refractory AML with chromosome 7 abnormalities (Patient 1, with inv(3)(q21;3q26.2) and monosomy 7; Patient 2, with der(7)t(1;7)(?;q22); patient 3, with monosomy 7) who were successfully treated with l -asparaginase (L-ASP) as salvage therapy. All three patients achieved CR several weeks after L-ASP treatment, and two patients successfully underwent hematopoietic stem cell transplantation (HSCT). Patient 2 relapsed after the second HSCT in the form of an intracranial lesion, but achieved and sustained CR for 3 years with weekly L-ASP maintenance therapy. Immunohistochemical staining for asparagine synthetase (ASNS), whose gene is located at 7q21.3, was performed for each patient. The result was negative in all patients, which suggests that haploid 7q21.3 and other chromosome 7 abnormalities leading to haploinsufficiency of ASNS contribute to a high susceptibility to L-ASP. In conclusion, L-ASP is a promising salvage therapy for refractory AML with chromosome 7 abnormalities, which are associated with ASNS haploinsufficiency.
Deciphering the Clinical Implications of Concurrent Chromosome 7 Gain and Chromosome 10 Loss in Glioblastoma: A Scoping Review
Background/Objectives: Combined chromosome 7 gain and chromosome 10 loss (+7/−10) is the most frequent cytogenetic alteration and a defining diagnostic criterion for isocitrate dehydrogenase wild-type (IDHwt) glioblastoma. Despite the association with poor prognosis, its clinical and therapeutic significance remains unclear. We aim to systematically review its clinical significance, focusing on prevalence, prognostic value, and potential association with therapeutic resistance in adult patients. Methods: PubMed, Embase, CENTRAL, Scopus, EBSCOhost, and Web of Science were searched from inception to April 2025, using controlled vocabulary and free-text terms. Eligible studies included adult glioblastoma with molecular confirmation of combined chromosome 7 gain and chromosome 10 loss and reported survival or treatment response. Quality was assessed qualitatively, and findings were synthesized descriptively. Results: Of 3249 records, 5 observational studies (523 patients) were included. The signature was present in 60% to 70% of glioblastoma cases and frequently co-occurred with epidermal growth factor receptor amplification and telomerase reverse transcriptase promoter mutations. This alteration was consistently associated with shorter survival (mean, 8–70 weeks) compared with tumors lacking the alteration (19–170 weeks). In one study, the signature was more common in radioresistant tumors (9/20 vs. 1/10). Molecular evidence suggests that this alteration arises early in tumorigenesis. Conclusions: The +7/−10 cytogenetic alteration, common in glioblastoma, is frequently associated with aggressive clinical behavior. While exploratory data suggest a possible association with radiotherapy response, current evidence is insufficient to establish a predictive or therapeutic role. Its principal clinical value lies in diagnosis, molecular classification, and risk stratification. Incorporating cytogenetic testing for this alteration into routine glioblastoma workup may improve risk stratification and guide individualized management.
Whole Exome Sequencing Identifies Novel Recurrently Mutated Genes in Patients with Splenic Marginal Zone Lymphoma
The pathogenesis of splenic marginal zone lymphoma (SMZL) remains largely unknown. Recent high-throughput sequencing studies have identified recurrent mutations in key pathways, most notably NOTCH2 mutations in >25% of patients. These studies are based on small, heterogeneous discovery cohorts, and therefore only captured a fraction of the lesions present in the SMZL genome. To identify further novel pathogenic mutations within related biochemical pathways, we applied whole exome sequencing (WES) and copy number (CN) analysis to a biologically and clinically homogeneous cohort of seven SMZL patients with 7q abnormalities and IGHV1-2*04 gene usage. We identified 173 somatic non-silent variants, affecting 160 distinct genes. In additional to providing independent validation of the presence of mutation in several previously reported genes (NOTCH2, TNFAIP3, MAP3K14, MLL2 and SPEN), our study defined eight additional recurrently mutated genes in SMZL; these genes are CREBBP, CBFA2T3, AMOTL1, FAT4, FBXO11, PLA2G4D, TRRAP and USH2A. By integrating our WES and CN data we identified three mutated putative candidate genes targeted by 7q deletions (CUL1, EZH2 and FLNC), with FLNC positioned within the well-characterized 7q minimally deleted region. Taken together, this work expands the reported directory of recurrently mutated cancer genes in this disease, thereby expanding our understanding of SMZL pathogenesis. Ultimately, this work will help to establish a stratified approach to care including the possibility of targeted therapy.
Single cell T cell landscape and T cell receptor repertoire profiling of AML in context of PD-1 blockade therapy
In contrast to the curative effect of allogenic stem cell transplantation in acute myeloid leukemia via T cell activity, only modest responses are achieved with checkpoint-blockade therapy, which might be explained by T cell phenotypes and T cell receptor (TCR) repertoires. Here, we show by paired single-cell RNA analysis and TCR repertoire profiling of bone marrow cells in relapsed/refractory acute myeloid leukemia patients pre/post azacytidine+nivolumab treatment that the disease-related T cell subsets are highly heterogeneous, and their abundance changes following PD-1 blockade-based treatment. TCR repertoires expand and primarily emerge from CD8 + cells in patients responding to treatment or having a stable disease, while TCR repertoires contract in therapy - resistant patients. Trajectory analysis reveals a continuum of CD8 + T cell phenotypes, characterized by differential expression of granzyme B and a bone marrow-residing memory CD8 + T cell subset, in which a population with stem-like properties expressing granzyme K is enriched in responders. Chromosome 7/7q loss, on the other hand, is a cancer-intrinsic genomic marker of PD-1 blockade resistance in AML. In summary, our study reveals that adaptive T cell plasticity and genomic alterations determine responses to PD-1 blockade in acute myeloid leukemia. The response rate of relapsed/refractory acute myeloid leukemia patients to PD-1 checkpoint blockade is low and unpredictable. Authors here show by single cell RNA sequencing, T cell receptor profiling and genomic analysis that the phenotypes and repertoire of CD8 + T cells and loss of chromosome 7/7q are important determinants of response.
Monosomal karyotype predicts poor survival after allogeneic stem cell transplantation in chromosome 7 abnormal myelodysplastic syndrome and secondary acute myeloid leukemia
Treatment algorithms for poor cytogenetic-risk myelodysplastic syndrome (MDS), defined by chromosome 7 abnormalities or complex karyotype (CK), include allogeneic stem cell transplantation (alloSCT). We studied outcome of alloSCT in chromosome 7 abnormal MDS patients as this data are scarce in literature. We specifically focused on the impact of the extra presence of CK and monosomal karyotype (MK). The European Group for Blood and Marrow Transplantation database contained data on 277 adult MDS patients with a chromosome 7 abnormality treated with alloSCT. Median age at alloSCT was 45 years. Median follow-up of patients alive was 5 years. Five-year progression-free survival (PFS) and overall survival (OS) were 22% and 28%, respectively. In multivariate analysis, statistically significant predictors for worse PFS were higher MDS stages treated, but not in complete remission (CR) (hazards ratio (HR) 1.7), and the presence of CK (HR 1.5) or MK (HR 1.8). Negative predictive factors for OS were higher MDS stages treated, but not in CR (HR 1.8), and the presence of CK (HR 1.6) or MK (HR 1.7). By means of the cross-validated log partial likelihood, MK showed to have a better predictive value than CK. The results are relevant when considering alloSCT for higher-stage MDS patients having MK including a chromosome 7 abnormality.
Glioblastomas with primitive neuronal component harbor a distinct methylation and copy-number profile with inactivation of TP53, PTEN, and RB1
Glioblastoma IDH-wildtype presents with a wide histological spectrum. Some features are so distinctive that they are considered as separate histological variants or patterns for the purpose of classification. However, these usually lack defined (epi-)genetic alterations or profiles correlating with this histology. Here, we describe a molecular subtype with overlap to the unique histological pattern of glioblastoma with primitive neuronal component. Our cohort consists of 63 IDH-wildtype glioblastomas that harbor a characteristic DNA methylation profile. Median age at diagnosis was 59.5 years. Copy-number variations and genetic sequencing revealed frequent alterations in TP53, RB1 and PTEN, with fewer gains of chromosome 7 and homozygous CDKN2A/B deletions than usually described for IDH-wildtype glioblastoma. Gains of chromosome 1 were detected in more than half of the cases. A poorly differentiated phenotype with frequent absence of GFAP expression, high proliferation index and strong staining for p53 and TTF1 often caused misleading histological classification as carcinoma metastasis or primitive neuroectodermal tumor. Clinically, many patients presented with leptomeningeal dissemination and spinal metastasis. Outcome was poor with a median overall survival of only 12 months. Overall, we describe a new molecular subtype of IDH-wildtype glioblastoma with a distinct histological appearance and genetic signature.