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2.
Nat Commun ; 12(1): 5238, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34475389

RESUMO

The most common events in breast cancer (BC) involve chromosome arm losses and gains. Here we describe identification of 1089 gene-centric common insertion sites (gCIS) from transposon-based screens in 8 mouse models of BC. Some gCIS are driver-specific, others driver non-specific, and still others associated with tumor histology. Processes affected by driver-specific and histology-specific mutations include well-known cancer pathways. Driver non-specific gCIS target the Mediator complex, Ca++ signaling, Cyclin D turnover, RNA-metabolism among other processes. Most gCIS show single allele disruption and many map to genomic regions showing high-frequency hemizygous loss in human BC. Two gCIS, Nf1 and Trps1, show synthetic haploinsufficient tumor suppressor activity. Many gCIS act on the same pathway responsible for tumor initiation, thereby selecting and sculpting just enough and just right signaling. These data highlight ~1000 genes with predicted conditional haploinsufficient tumor suppressor function and the potential to promote chromosome arm loss in BC.


Assuntos
Neoplasias da Mama/genética , Perda de Heterozigosidade/genética , Animais , Neoplasias da Mama/patologia , Transformação Celular Neoplásica , Elementos de DNA Transponíveis/genética , Feminino , Genes Supressores de Tumor , Humanos , Camundongos , Mutagênese Insercional , Neoplasias Experimentais , Transdução de Sinais
3.
Nat Commun ; 12(1): 4922, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389729

RESUMO

CRISPR-Cas9 is a promising technology for gene therapy. However, the ON-target genotoxicity of CRISPR-Cas9 nuclease due to DNA double-strand breaks has received little attention and is probably underestimated. Here we report that genome editing targeting globin genes induces megabase-scale losses of heterozygosity (LOH) from the globin CRISPR-Cas9 cut-site to the telomere (5.2 Mb). In established lines, CRISPR-Cas9 nuclease induces frequent terminal chromosome 11p truncations and rare copy-neutral LOH. In primary hematopoietic progenitor/stem cells, we detect 1.1% of clones (7/648) with acquired megabase LOH induced by CRISPR-Cas9. In-depth analysis by SNP-array reveals the presence of copy-neutral LOH. This leads to 11p15.5 partial uniparental disomy, comprising two Chr11p15.5 imprinting centers (H19/IGF2:IG-DMR/IC1 and KCNQ1OT1:TSS-DMR/IC2) and impacting H19 and IGF2 expression. While this genotoxicity is a safety concern for CRISPR clinical trials, it is also an opportunity to model copy-neutral-LOH for genetic diseases and cancers.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes/métodos , Globinas/genética , Células-Tronco Hematopoéticas/metabolismo , Perda de Heterozigosidade/genética , Deleção de Sequência , Células Cultivadas , Deleção Cromossômica , Cromossomos Humanos Par 11/genética , Metilação de DNA , Expressão Gênica , Células HEK293 , Células-Tronco Hematopoéticas/citologia , Humanos , Fator de Crescimento Insulin-Like II/genética , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante/genética
4.
HLA ; 98(3): 207-212, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34288574

RESUMO

Leukemia is a complex disease in which mutations and other genomic and epigenomic abnormalities play a role in both its initiation and progression. Acute lymphoid leukemia (ALL) patients with loss of heterozygosity (LOH) in the HLA region before transplantation have been described rarely. In this report, we described two ALL cases with LOH encompassing the HLA, wholly or partly. HLA molecular typing was performed on peripheral blood (PB) and somatic cell. Simultaneously, we performed whole-exome sequencing. Typing results on PB samples collected during blast crisis demonstrated complete or partial homozygosity at the -A, -B, -C, -DR, and -DQ loci. Two somatic samples demonstrated heterozygosity at all loci. LOH at the HLA gene locus may significantly influence the donor search, resulting in misidentification of homozygous donors. We recommend confirming the patients' HLA typing with hematological malignancies when homozygosity is detected at any locus by using somatic samples or alternatively from PB when remission is achieved.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Alelos , Teste de Histocompatibilidade , Humanos , Perda de Heterozigosidade
5.
Gene ; 801: 145851, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34274474

RESUMO

Sertoli cell only syndrome (SCOS) is characterized by complete absence of germ cells in seminiferous tubules of testis. SCOS is multifactorial but genetic factors play a major role in pathogenesis of the disorder with idiopathic origin. Genetic factors majorly include sex chromosomal aneuploidy and Yq Microdeletion. But a large number of cases are still idiopathic. The study aimed to evaluate the genomic imbalances (CNVs and LOH) in idiopathic SCOS patients. The study is based on 28 apparent idiopathic SCOS cases and 10 controls. Molecular cytogenetic techniques viz., FISH, STS-Multiplex PCR and Affymetrix cytoscan microarray (750 K) were used. The microarray screened whole genomic imbalances in DNA from peripheral blood of 25 cases (excluded Klinefelter syndrome patients) and testicular FNAC sample of 2 cases. High FSH and low Inhibin B were observed in cases as compared to control controls groups. Four cases of sex chromosomal abnormality (i.e., three non-mosaic 47, XXY males and one non-mosaic 46, XX male) as well as four cases of Yq microdeletion (i.e., three cases with AZFc deletion and one case with complete AZFa, b and c deletion) were identified. Microarray detected unbalanced translocation of two segments of Y-chromosome i.e., Yp11.31-p11.2 (~4.o mb region, involving SRY) and Yp11.2 (~2.5 mb region) on X-chromosome in XX male. Also, loss of segment on same X-chromosome involving PAR1 region was identified. We have identified both autosomal and sex chromosomal CNVs (recurrent as well as private) involving candidate genes like SYCE1, ZFPM2, SRPK1, DAZ1, BPY2, HSFY1, VCY1 etc. All these CNVs are possibly associated with SCOS pathogenesis. CNVs identified in cases were already reported as pathogenic variant in clinical database DECIPHER. Microarray also detected many LOH (all autosomal, >3.0 mb size) that covered genes with spermatogenesis related function. The mechanism of action of LOH in pathogenesis of SCOS still remains unravelled. CNVs and LOH related to spermatogenesis identified from two different sample types (blood vs. testicular tissue) were discordant. This study should be extended for larger cohort of patients.


Assuntos
Variações do Número de Cópias de DNA , Perda de Heterozigosidade , Síndrome de Células de Sertoli/genética , Aberrações dos Cromossomos Sexuais , Hormônio Antimülleriano/sangue , Azoospermia/genética , Estudos de Casos e Controles , Análise Citogenética/métodos , Humanos , Hibridização in Situ Fluorescente , Subunidades beta de Inibinas/sangue , Masculino , Testículo/fisiologia
6.
Eur J Endocrinol ; 185(4): 485-496, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34313605

RESUMO

Objective: Pituitary adenomas (PA) are rare in young patients, and additional studies are needed to fully understand their pathogenesis in this population. We describe the clinical and genetic characteristics of apparently sporadic PA in a cohort of young patients. Design: Clinical and molecular analysis of 235 patients (age ≤ 30 years) with PA. Clinicians from several Spanish and Chilean hospitals provided data. Methods: Genetic screening was performed via next-generation sequencing and comparative genomic hybridization array. Clinical variables were compared among paediatric, adolescent (<19 years) and young adults' (≥19-30 years) cohorts and types of adenomas. Phenotype-genotype associations were examined. Results: Among the total cohort, mean age was 17.3 years. Local mass effect symptoms were present in 22.0%, and prolactinomas were the most frequent (44.7%). Disease-causing germline variants were identified in 22 individuals (9.3%), more exactly in 13.1 and 4.7% of the populations aged between 0-19 and 19-30 years, respectively; genetically positive patients were younger at diagnosis and had larger tumour size. Healthy family carriers were also identified. Conclusions: Variants in genes associated with syndromic forms of PAs were detected in a large cohort of apparently sporadic pituitary tumours. We have identified novel variants in well-known genes and set the possibility of incomplete disease penetrance in carriers of MEN1 alterations or a limited clinical expression of the syndrome. Despite the low penetrance observed, screening of AIP and MEN1 variants in young patients and relatives is of clinical value.


Assuntos
Adenoma , Neoplasias Hipofisárias , Adenoma/diagnóstico , Adenoma/epidemiologia , Adenoma/genética , Adolescente , Adulto , Idade de Início , Criança , Pré-Escolar , Chile/epidemiologia , Estudos de Coortes , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Testes Genéticos , Mutação em Linhagem Germinativa , Humanos , Lactente , Recém-Nascido , Perda de Heterozigosidade , Masculino , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/epidemiologia , Neoplasias Hipofisárias/genética , Espanha/epidemiologia , Adulto Jovem
7.
Elife ; 102021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34159898

RESUMO

The dynamics and diversity of the appearance of genetic variants play an essential role in the evolution of the genome and the shaping of biodiversity. Recent population-wide genome sequencing surveys have highlighted the importance of loss of heterozygosity (LOH) events and have shown that they are a neglected part of the genetic diversity landscape. To assess the extent, variability, and spectrum, we explored the accumulation of LOH events in 169 heterozygous diploid Saccharomyces cerevisiae mutation accumulation lines across nine genetic backgrounds. In total, we detected a large set of 22,828 LOH events across distinct genetic backgrounds with a heterozygous level ranging from 0.1% to 1%. LOH events are very frequent with a rate consistently much higher than the mutation rate, showing their importance for genome evolution. We observed that the interstitial LOH (I-LOH) events, resulting in internal short LOH tracts, were much frequent (n = 19,660) than the terminal LOH (T-LOH) events, that is, tracts extending to the end of the chromosome (n = 3168). However, the spectrum, the rate, and the fraction of the genome under LOH vary across genetic backgrounds. Interestingly, we observed that the more the ancestors were heterozygous, the more they accumulated T-LOH events. In addition, frequent short I-LOH tracts are a signature of the lines derived from hybrids with low spore fertility. Finally, we found lines showing almost complete homozygotization during vegetative progression. Overall, our results highlight that the variable dynamics of the LOH accumulation across distinct genetic backgrounds might lead to rapid differential genome evolution during vegetative growth.


Assuntos
Patrimônio Genético , Genoma Fúngico , Perda de Heterozigosidade , Acúmulo de Mutações , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
8.
Nat Commun ; 12(1): 4019, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34188043

RESUMO

The vast majority of human tumors with p53 mutations undergo loss of the remaining wildtype p53 allele (loss-of-heterozygosity, p53LOH). p53LOH has watershed significance in promoting tumor progression. However, driving forces for p53LOH are poorly understood. Here we identify the repressive WTp53-HSF1 axis as one driver of p53LOH. We find that the WTp53 allele in AOM/DSS chemically-induced colorectal tumors (CRC) of p53R248Q/+ mice retains partial activity and represses heat-shock factor 1 (HSF1), the master regulator of the proteotoxic stress response (HSR) that is ubiquitously activated in cancer. HSR is critical for stabilizing oncogenic proteins including mutp53. WTp53-retaining CRC tumors, tumor-derived organoids and human CRC cells all suppress the tumor-promoting HSF1 program. Mechanistically, retained WTp53 activates CDKN1A/p21, causing cell cycle inhibition and suppression of E2F target MLK3. MLK3 links cell cycle with the MAPK stress pathway to activate the HSR response. In p53R248Q/+ tumors WTp53 activation by constitutive stress represses MLK3, thereby weakening the MAPK-HSF1 response necessary for tumor survival. This creates selection pressure for p53LOH which eliminates the repressive WTp53-MAPK-HSF1 axis and unleashes tumor-promoting HSF1 functions, inducing mutp53 stabilization enabling invasion.


Assuntos
Pontos de Checagem do Ciclo Celular/genética , Neoplasias Colorretais/patologia , Fatores de Transcrição de Choque Térmico/metabolismo , Perda de Heterozigosidade/genética , Proteína Supressora de Tumor p53/metabolismo , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Células HCT116 , Células HEK293 , Humanos , MAP Quinase Quinase Quinases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação/genética , Proteína Supressora de Tumor p53/genética
9.
Virchows Arch ; 479(1): 221-226, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34100114

RESUMO

Salivary gland cancers (SGCs) are rare malignancies with highly heterogeneous histological features. Patients affected with SGCs are at increased risk of secondary malignancies, including breast cancer (BC). Previous studies enlightened a possible link between SGCs and hereditary predisposition to BC. Here, we searched for SGC-affected patients in 1796 high-risk BC families recruited at the Genetic Unit of the Istituto Nazionale dei Tumori of Milan, 516 of which carried pathogenic variants in BRCA1 and/or BRCA2, the main genetic risk factors for BC. We detected five families with an individual affected with SGC, including two male patients, one carrying a constitutional mutation in BRCA1 and the other in BRCA2. Loss of heterozygosity of BRCA wild-type alleles was assessed in the patients' tumour DNA. We conclude that our observations support the hypothesis that genetic factors associated with BC susceptibility might play a role also in at least a subset of SGCs.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Mutação , Neoplasias das Glândulas Salivares/genética , Adulto , Bases de Dados Factuais , Feminino , Predisposição Genética para Doença , Hereditariedade , Humanos , Itália , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Linhagem
10.
BMC Cancer ; 21(1): 561, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001010

RESUMO

BACKGROUND: Oral Potentially Malignant Disorders (OPMD) have a non-negligible malignant transformation rate of up to 8%. Loss of heterozygosity (LOH) in critical chromosomal loci has proven to be the most effective marker in defining the risk of transformation and it is found in about 28% of OPMD and may therefore identify patients carrying higher risk. To date, clinical management of OPMD is limited to surgical excision and clinical surveillance, which however do not fully prevent oral cancer development. Immune system has been shown to play a key role in transformation surveillance mechanism and an immunosuppressive imbalance may be responsible for progression to cancer. Given all these considerations, we designed a clinical trial with the aim to prevent OPMD neoplastic transformation and revert the LOH status. METHODS: This is a phase II, open label, single arm, multicentric trial involving Italian referral centres and expected to enrol 80 patients out of a total of 175 screened. Patients who meet all inclusion criteria and test positive for LOH after an incisional biopsy of the OPMD will undergo a short course of immunotherapy with 4 administration of avelumab. After 6 months since treatment start, resection of the entire OPMD will be performed and LOH assessment will be repeated. The follow-up for malignant transformation and safety assessment will last 30 months from the end of treatment, for a total planned study duration of approximately 5.5 years. DISCUSSION: Restoring the activity of immune system through checkpoint inhibitor may play a crucial role against malignant transformation of OPMD by reverting the balance in favour of immune control and preventing cancer occurrence. TRIAL REGISTRATION: This trial was prospectively registered in ClinicalTrials.gov as NCT04504552 on 7th August 2020.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Inibidores de Checkpoint Imunológico/administração & dosagem , Neoplasias Bucais/epidemiologia , Lesões Pré-Cancerosas/tratamento farmacológico , Evasão Tumoral/efeitos dos fármacos , Adulto , Anticorpos Monoclonais Humanizados/efeitos adversos , Antígeno B7-H1/antagonistas & inibidores , Ensaios Clínicos Fase II como Assunto , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Itália/epidemiologia , Perda de Heterozigosidade , Masculino , Neoplasias Bucais/genética , Neoplasias Bucais/imunologia , Neoplasias Bucais/prevenção & controle , Estudos Multicêntricos como Assunto , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/imunologia , Lesões Pré-Cancerosas/mortalidade , Recidiva , Evasão Tumoral/genética , Evasão Tumoral/imunologia , Adulto Jovem
11.
BMC Cancer ; 21(1): 593, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34030643

RESUMO

BACKGROUND: ATLAS evaluated the efficacy and safety of the PARP inhibitor rucaparib in patients with previously treated locally advanced/unresectable or metastatic urothelial carcinoma (UC). METHODS: Patients with UC were enrolled independent of tumor homologous recombination deficiency (HRD) status and received rucaparib 600 mg BID. The primary endpoint was investigator-assessed objective response rate (RECIST v1.1) in the intent-to-treat and HRD-positive (loss of genome-wide heterozygosity ≥10%) populations. Key secondary endpoints were progression-free survival (PFS) and safety. Disease control rate (DCR) was defined post-hoc as the proportion of patients with a confirmed complete or partial response (PR), or stable disease lasting ≥16 weeks. RESULTS: Of 97 enrolled patients, 20 (20.6%) were HRD-positive, 30 (30.9%) HRD-negative, and 47 (48.5%) HRD-indeterminate. Among 95 evaluable patients, there were no confirmed responses. However, reductions in the sum of target lesions were observed, including 6 (6.3%) patients with unconfirmed PR. DCR was 11.6%; median PFS was 1.8 months (95% CI, 1.6-1.9). No relationship was observed between HRD status and efficacy endpoints. Median treatment duration was 1.8 months (range, 0.1-10.1). Most frequent any-grade treatment-emergent adverse events were asthenia/fatigue (57.7%), nausea (42.3%), and anemia (36.1%). Of 64 patients with data from tumor tissue samples, 10 (15.6%) had a deleterious alteration in a DNA damage repair pathway gene, including four with a deleterious BRCA1 or BRCA2 alteration. CONCLUSIONS: Rucaparib did not show significant activity in unselected patients with advanced UC regardless of HRD status. The safety profile was consistent with that observed in patients with ovarian or prostate cancer. TRIAL REGISTRATION: This trial was registered in ClinicalTrials.gov (NCT03397394). Date of registration: 12 January 2018. This trial was registered in EudraCT (2017-004166-10).


Assuntos
Carcinoma de Células de Transição/tratamento farmacológico , Indóis/administração & dosagem , Inibidores de Poli(ADP-Ribose) Polimerases/administração & dosagem , Neoplasias da Bexiga Urinária/tratamento farmacológico , Administração Oral , Idoso , Proteína BRCA1/genética , Proteína BRCA2/genética , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/secundário , Reparo do DNA , Feminino , Seguimentos , Humanos , Indóis/efeitos adversos , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Inibidores de Poli(ADP-Ribose) Polimerases/efeitos adversos , Intervalo Livre de Progressão , Critérios de Avaliação de Resposta em Tumores Sólidos , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
12.
Am Nat ; 197(6): 658-676, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33989142

RESUMO

AbstractInbreeding depression is often found in small, inbred populations, but whether it can be detected in and have evolutionary consequences for large, wide-ranging populations is poorly known. Here, we investigate the possibility of inbreeding in a large population to determine whether mild levels of inbreeding can still have genetic and phenotypic consequences and how genomically widespread these effects can be. We apply genome-wide methods to investigate whether individual and parental heterozygosity is related to morphological, growth, or life-history traits in a pelagic seabird, Leach's storm-petrel (Oceanodroma leucorhoa). Examining 560 individuals as part of a multiyear study, we found a substantial effect of maternal heterozygosity on chick traits: chicks from less heterozygous (relatively inbred) mothers were significantly smaller than chicks from more heterozygous (noninbred) mothers. We show that these heterozygosity-fitness correlations were due to general genome-wide effects and demonstrate a correlation between heterozygosity and inbreeding, suggesting inbreeding depression. We used population genetic models to further show that the variance in inbreeding was probably due to past demographic events rather than the current mating system and ongoing mate choice. Our findings demonstrate that inbreeding depression can be observed in large populations and illustrate how the integration of genomic techniques and fieldwork can elucidate its underlying causes.


Assuntos
Depressão por Endogamia , Endogamia , Perda de Heterozigosidade , Animais , Aves/classificação , Aves/genética , Tamanho Corporal/genética , Demografia , Genômica , Perda de Heterozigosidade/fisiologia
13.
Am J Hum Genet ; 108(6): 1069-1082, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34022130

RESUMO

BCAS3 microtubule-associated cell migration factor (BCAS3) is a large, highly conserved cytoskeletal protein previously proposed to be critical in angiogenesis and implicated in human embryogenesis and tumorigenesis. Here, we established BCAS3 loss-of-function variants as causative for a neurodevelopmental disorder. We report 15 individuals from eight unrelated families with germline bi-allelic loss-of-function variants in BCAS3. All probands share a global developmental delay accompanied by pyramidal tract involvement, microcephaly, short stature, strabismus, dysmorphic facial features, and seizures. The human phenotype is less severe compared with the Bcas3 knockout mouse model and cannot be explained by angiogenic defects alone. Consistent with being loss-of-function alleles, we observed absence of BCAS3 in probands' primary fibroblasts. By comparing the transcriptomic and proteomic data based on probands' fibroblasts with those of the knockout mouse model, we identified similar dysregulated pathways resulting from over-representation analysis, while the dysregulation of some proposed key interactors could not be confirmed. Together with the results from a tissue-specific Drosophila loss-of-function model, we demonstrate a vital role for BCAS3 in neural tissue development.


Assuntos
Mutação com Perda de Função , Perda de Heterozigosidade , Proteínas de Neoplasias/genética , Transtornos do Neurodesenvolvimento/etiologia , Adolescente , Adulto , Animais , Movimento Celular , Criança , Pré-Escolar , Drosophila , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Lactente , Masculino , Camundongos , Camundongos Knockout , Proteínas de Neoplasias/metabolismo , Transtornos do Neurodesenvolvimento/metabolismo , Transtornos do Neurodesenvolvimento/patologia , Linhagem , Proteoma/análise , Adulto Jovem
14.
Radiat Res ; 196(2): 225-234, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34046685

RESUMO

Neutron radiation, a high-linear energy transfer radiation, has a high relative biological effectiveness (RBE) for various end points. The age at exposure is an important modifier of the effects of radiation, including carcinogenesis, with infants being generally more radiosensitive. Ptch1+/- mice offer a unique experimental system for assessing radiation carcinogenesis. Spontaneous development of medulloblastoma tumors occurs in nonirradiated animals that lose their Ptch1+ allele, most frequently by a loss of heterozygosity (LOH) of chromosome 13 via recombination or non-disjunction (referred to as S-type tumors). In contrast, tumors occur in irradiated Ptch1+/- mice as a result of chromosome 13 LOH with an interstitial deletion (R-type), making spontaneous and radiation-induced tumors discernible. To elucidate the influence of age on the effect of fast neutrons, we irradiated Ptch1+/- mice with neutrons (mean energy, ∼2 MeV) or γ rays on embryonic day (E)14 and E17 and on postnatal day (P)1, 4 or 10 and classified the resulting medulloblastomas based on chromosome 13 aberrations. Instead of LOH, some tumors harbored mutations in their Ptch1+ gene via a nonirradiation-associated mechanism such as duplication, insertion, base substitution or deletion with microhomology-mediated end joining; thus, these tumors were classified as S-type. The RBE regarding the induction of R-type tumors was 12.9 (8.6, 17.2), 9.6 (6.9, 12.3), 21.5 (17.2, 25.8), and 7.1 (4.7, 9.5) (mean and 95% confidence interval) for mice irradiated on E14, E17, P1 and P4, respectively, with the highest value seen during the most active development of the tissue and P10 being completely resistant. These results indicate that the developmental stage at exposure of the tissue influences the RBE of neutrons.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 13/efeitos da radiação , Meduloblastoma/genética , Neoplasias Induzidas por Radiação/genética , Receptor Patched-1/genética , Animais , Cromossomos Humanos Par 13/genética , Relação Dose-Resposta à Radiação , Nêutrons Rápidos/efeitos adversos , Humanos , Perda de Heterozigosidade/genética , Perda de Heterozigosidade/efeitos da radiação , Meduloblastoma/etiologia , Meduloblastoma/patologia , Camundongos , Neoplasias Induzidas por Radiação/patologia , Tolerância a Radiação/genética , Tolerância a Radiação/efeitos da radiação , Eficiência Biológica Relativa
15.
Cancer Sci ; 112(7): 2921-2927, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33934450

RESUMO

Mature teratomas are usually benign tumors that rarely undergo malignant transformation. We report an advanced neuroblastoma arising in a mature teratoma of the ovary. Whole-exome sequencing identified extensive copy-neutral loss of heterozygosity (LOH) in both neuroblastoma and teratoma elements, suggesting that the neuroblastoma evolved from the teratoma. In addition, several truncating germline heterozygous variants in tumor suppressor genes, including RBL2 and FBXW12, became homozygous as a result of LOH. Collectively, we speculate that extensive LOH in teratoma cells may force heterozygous germline variants to become homozygous, which, in turn, may contribute to the development of neuroblastoma with the acquisition of additional chromosomal changes.


Assuntos
Mutação em Linhagem Germinativa , Perda de Heterozigosidade , Neoplasias Primárias Múltiplas/genética , Neuroblastoma/genética , Neoplasias Ovarianas/genética , Teratoma/genética , Adolescente , Proteínas F-Box/genética , Feminino , Homozigoto , Humanos , Neoplasias Primárias Múltiplas/tratamento farmacológico , Neoplasias Primárias Múltiplas/patologia , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Proteína p130 Retinoblastoma-Like/genética , Teratoma/tratamento farmacológico , Teratoma/patologia , Sequenciamento Completo do Exoma
16.
Cancer Sci ; 112(7): 2781-2791, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33960594

RESUMO

The prevalence of neuroendocrine prostate cancer (NEPC) arising from adenocarcinoma (AC) upon potent androgen receptor (AR) pathway inhibition is increasing. Deeper understanding of NEPC biology and development of novel therapeutic agents are needed. However, research is hindered by the paucity of research models, especially cell lines developed from NEPC patients. We established a novel NEPC cell line, KUCaP13, from tissue of a patient initially diagnosed with AC which later recurred as NEPC. The cell line has been maintained permanently in vitro under regular cell culture conditions and is amenable to gene engineering with lentivirus. KUCaP13 cells lack the expression of AR and overexpress NEPC-associated genes, including SOX2, EZH2, AURKA, PEG10, POU3F2, ENO2, and FOXA2. Importantly, the cell line maintains the homozygous deletion of CHD1, which was confirmed in the primary AC of the index patient. Loss of heterozygosity of TP53 and PTEN, and an allelic loss of RB1 with a transcriptomic signature compatible with Rb pathway aberration were revealed. Knockdown of PEG10 using shRNA significantly suppressed growth in vivo. Introduction of luciferase allowed serial monitoring of cells implanted orthotopically or in the renal subcapsule. Although H3K27me was reduced by EZH2 inhibition, reversion to AC was not observed. KUCaP13 is the first patient-derived, treatment-related NEPC cell line with triple loss of tumor suppressors critical for NEPC development through lineage plasticity. It could be valuable in research to deepen the understanding of NEPC.


Assuntos
Adenocarcinoma/patologia , Carcinoma Neuroendócrino/patologia , Linhagem Celular Tumoral/patologia , Neoplasias da Próstata/patologia , Animais , Proteínas Reguladoras de Apoptose/genética , Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/secundário , Linhagem Celular Tumoral/metabolismo , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Ensaios de Seleção de Medicamentos Antitumorais , Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Deleção de Genes , Expressão Gênica , Genes Neoplásicos , Genes do Retinoblastoma , Genes Supressores de Tumor , Genes p53 , Engenharia Genética , Xenoenxertos , Homozigoto , Humanos , Cariotipagem , Perda de Heterozigosidade , Masculino , Camundongos SCID , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Transplante de Neoplasias , PTEN Fosfo-Hidrolase/genética , Neoplasias Penianas/genética , Neoplasias Penianas/secundário , Neoplasias da Próstata/genética , Proteínas de Ligação a RNA/genética , Receptores Androgênicos
17.
Am J Hum Genet ; 108(6): 1115-1125, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34010605

RESUMO

Importin 8, encoded by IPO8, is a ubiquitously expressed member of the importin-ß protein family that translocates cargo molecules such as proteins, RNAs, and ribonucleoprotein complexes into the nucleus in a RanGTP-dependent manner. Current knowledge of the cargoes of importin 8 is limited, but TGF-ß signaling components such as SMAD1-4 have been suggested to be among them. Here, we report that bi-allelic loss-of-function variants in IPO8 cause a syndromic form of thoracic aortic aneurysm (TAA) with clinical overlap with Loeys-Dietz and Shprintzen-Goldberg syndromes. Seven individuals from six unrelated families showed a consistent phenotype with early-onset TAA, motor developmental delay, connective tissue findings, and craniofacial dysmorphic features. A C57BL/6N Ipo8 knockout mouse model recapitulates TAA development from 8-12 weeks onward in both sexes but most prominently shows ascending aorta dilatation with a propensity for dissection in males. Compliance assays suggest augmented passive stiffness of the ascending aorta in male Ipo8-/- mice throughout life. Immunohistological investigation of mutant aortic walls reveals elastic fiber disorganization and fragmentation along with a signature of increased TGF-ß signaling, as evidenced by nuclear pSmad2 accumulation. RT-qPCR assays of the aortic wall in male Ipo8-/- mice demonstrate decreased Smad6/7 and increased Mmp2 and Ccn2 (Ctgf) expression, reinforcing a role for dysregulation of the TGF-ß signaling pathway in TAA development. Because importin 8 is the most downstream TGF-ß-related effector implicated in TAA pathogenesis so far, it offers opportunities for future mechanistic studies and represents a candidate drug target for TAA.


Assuntos
Aneurisma da Aorta Torácica/etiologia , Mutação com Perda de Função , Perda de Heterozigosidade , Fenótipo , beta Carioferinas/genética , Adulto , Animais , Aneurisma da Aorta Torácica/metabolismo , Aneurisma da Aorta Torácica/patologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linhagem , Transdução de Sinais , Síndrome , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Adulto Jovem , beta Carioferinas/metabolismo
18.
Am J Hum Genet ; 108(6): 1126-1137, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34010604

RESUMO

Dysregulated transforming growth factor TGF-ß signaling underlies the pathogenesis of genetic disorders affecting the connective tissue such as Loeys-Dietz syndrome. Here, we report 12 individuals with bi-allelic loss-of-function variants in IPO8 who presented with a syndromic association characterized by cardio-vascular anomalies, joint hyperlaxity, and various degree of dysmorphic features and developmental delay as well as immune dysregulation; the individuals were from nine unrelated families. Importin 8 belongs to the karyopherin family of nuclear transport receptors and was previously shown to mediate TGF-ß-dependent SMADs trafficking to the nucleus in vitro. The important in vivo role of IPO8 in pSMAD nuclear translocation was demonstrated by CRISPR/Cas9-mediated inactivation in zebrafish. Consistent with IPO8's role in BMP/TGF-ß signaling, ipo8-/- zebrafish presented mild to severe dorso-ventral patterning defects during early embryonic development. Moreover, ipo8-/- zebrafish displayed severe cardiovascular and skeletal defects that mirrored the human phenotype. Our work thus provides evidence that IPO8 plays a critical and non-redundant role in TGF-ß signaling during development and reinforces the existing link between TGF-ß signaling and connective tissue defects.


Assuntos
Doenças Ósseas/etiologia , Doenças Cardiovasculares/etiologia , Doenças do Tecido Conjuntivo/etiologia , Imunidade Celular/imunologia , Mutação com Perda de Função , Perda de Heterozigosidade , beta Carioferinas/genética , Adolescente , Adulto , Animais , Doenças Ósseas/patologia , Doenças Cardiovasculares/patologia , Criança , Doenças do Tecido Conjuntivo/patologia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Transdução de Sinais , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Adulto Jovem , Peixe-Zebra , beta Carioferinas/metabolismo
19.
Lancet Oncol ; 22(6): 813-823, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34000245

RESUMO

BACKGROUND: The CATNON trial investigated the addition of concurrent, adjuvant, and both current and adjuvant temozolomide to radiotherapy in adults with newly diagnosed 1p/19q non-co-deleted anaplastic gliomas. The benefit of concurrent temozolomide chemotherapy and relevance of mutations in the IDH1 and IDH2 genes remain unclear. METHODS: This randomised, open-label, phase 3 study done in 137 institutions across Australia, Europe, and North America included patients aged 18 years or older with newly diagnosed 1p/19q non-co-deleted anaplastic gliomas and a WHO performance status of 0-2. Patients were randomly assigned (1:1:1:1) centrally using a minimisation technique to radiotherapy alone (59·4 Gy in 33 fractions; three-dimensional conformal radiotherapy or intensity-modulated radiotherapy), radiotherapy with concurrent oral temozolomide (75 mg/m2 per day), radiotherapy with adjuvant oral temozolomide (12 4-week cycles of 150-200 mg/m2 temozolomide given on days 1-5), or radiotherapy with both concurrent and adjuvant temozolomide. Patients were stratified by institution, WHO performance status score, age, 1p loss of heterozygosity, the presence of oligodendroglial elements on microscopy, and MGMT promoter methylation status. The primary endpoint was overall survival adjusted by stratification factors at randomisation in the intention-to-treat population. A second interim analysis requested by the independent data monitoring committee was planned when two-thirds of total required events were observed to test superiority or futility of concurrent temozolomide. This study is registered with ClinicalTrials.gov, NCT00626990. FINDINGS: Between Dec 4, 2007, and Sept 11, 2015, 751 patients were randomly assigned (189 to radiotherapy alone, 188 to radiotherapy with concurrent temozolomide, 186 to radiotherapy and adjuvant temozolomide, and 188 to radiotherapy with concurrent and adjuvant temozolomide). Median follow-up was 55·7 months (IQR 41·0-77·3). The second interim analysis declared futility of concurrent temozolomide (median overall survival was 66·9 months [95% CI 45·7-82·3] with concurrent temozolomide vs 60·4 months [45·7-71·5] without concurrent temozolomide; hazard ratio [HR] 0·97 [99·1% CI 0·73-1·28], p=0·76). By contrast, adjuvant temozolomide improved overall survival compared with no adjuvant temozolomide (median overall survival 82·3 months [95% CI 67·2-116·6] vs 46·9 months [37·9-56·9]; HR 0·64 [95% CI 0·52-0·79], p<0·0001). The most frequent grade 3 and 4 toxicities were haematological, occurring in no patients in the radiotherapy only group, 16 (9%) of 185 patients in the concurrent temozolomide group, and 55 (15%) of 368 patients in both groups with adjuvant temozolomide. No treatment-related deaths were reported. INTERPRETATION: Adjuvant temozolomide chemotherapy, but not concurrent temozolomide chemotherapy, was associated with a survival benefit in patients with 1p/19q non-co-deleted anaplastic glioma. Clinical benefit was dependent on IDH1 and IDH2 mutational status. FUNDING: Merck Sharpe & Dohme.


Assuntos
Glioma/tratamento farmacológico , Isocitrato Desidrogenase/genética , Temozolomida/administração & dosagem , Adolescente , Adulto , Idoso , Austrália , Quimioterapia Adjuvante , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 19/genética , Terapia Combinada , Dacarbazina/administração & dosagem , Dacarbazina/efeitos adversos , Europa (Continente) , Feminino , Glioma/genética , Glioma/patologia , Glioma/radioterapia , Humanos , Perda de Heterozigosidade/genética , Masculino , Pessoa de Meia-Idade , América do Norte , Radioterapia Conformacional , Adulto Jovem
20.
PLoS One ; 16(4): e0250856, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33914812

RESUMO

Glycolytic metabolism is closely involved in physiological homeostasis and pathophysiological states. Among glycolytic enzymes, phosphoglycerate mutase (PGAM) has been reported to exert certain physiological role in vitro, whereas its impact on glucose metabolism in vivo remains unclear. Here, we report the characterization of Pgam1 knockout mice. We observed that homozygous knockout mice of Pgam1 were embryonic lethal. Although we previously reported that both PGAM-1 and -2 affect global glycolytic profile of cancers in vitro, in vivo glucose parameters were less affected both in the heterozygous knockout of Pgam1 and in Pgam2 transgenic mice. Thus, the impact of PGAM on in vivo glucose metabolism is rather complex than expected before.


Assuntos
Genes Letais , Glucose/metabolismo , Fosfoglicerato Mutase/genética , Animais , Técnicas de Inativação de Genes , Glicólise , Perda de Heterozigosidade , Masculino , Camundongos , Camundongos Transgênicos
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