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1.
Nucleus ; 15(1): 2339214, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38597409

RESUMO

The nuclear lamina (NL) changes composition for regulation of nuclear events. We investigated changes that occur in Drosophila oogenesis, revealing switches in NL composition during germ cell differentiation. Germline stem cells (GSCs) express only LamB and predominantly emerin, whereas differentiating nurse cells predominantly express LamC and emerin2. A change in LamC-specific localization also occurs, wherein phosphorylated LamC redistributes to the nuclear interior only in the oocyte, prior to transcriptional reactivation of the meiotic genome. These changes support existing concepts that LamC promotes differentiation, a premise that was tested. Remarkably ectopic LamC production in GSCs did not promote premature differentiation. Increased LamC levels in differentiating germ cells altered internal nuclear structure, increased RNA production, and reduced female fertility due to defects in eggshell formation. These studies suggest differences between Drosophila lamins are regulatory, not functional, and reveal an unexpected robustness to level changes of a major scaffolding component of the NL.


Assuntos
Proteínas de Drosophila , Lâmina Nuclear , Animais , Feminino , Drosophila melanogaster/genética , Proteínas de Drosophila/genética , Drosophila , Diferenciação Celular , Células Germinativas
2.
Development ; 151(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38607588

RESUMO

The germline provides the genetic and non-genetic information that passes from one generation to the next. Given this important role in species propagation, egg and sperm precursors, called primordial germ cells (PGCs), are one of the first cell types specified during embryogenesis. In fact, PGCs form well before the bipotential somatic gonad is specified. This common feature of germline development necessitates that PGCs migrate through many tissues to reach the somatic gonad. During their journey, PGCs must respond to select environmental cues while ignoring others in a dynamically developing embryo. The complex multi-tissue, combinatorial nature of PGC migration is an excellent model for understanding how cells navigate complex environments in vivo. Here, we discuss recent findings on the migratory path, the somatic cells that shepherd PGCs, the guidance cues somatic cells provide, and the PGC response to these cues to reach the gonad and establish the germline pool for future generations. We end by discussing the fate of wayward PGCs that fail to reach the gonad in diverse species. Collectively, this field is poised to yield important insights into emerging reproductive technologies.


Assuntos
Células Germinativas , Sêmen , Masculino , Humanos , Espermatozoides , Sinais (Psicologia) , Movimento Celular
3.
Int J Mol Sci ; 25(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38612451

RESUMO

Reproduction is the important process of transmitting one's genetic information to the next generation [...].


Assuntos
Células Germinativas , Neoplasias , Genitália , Reprodução , Biologia
4.
Cancer Med ; 13(7): e7166, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38572926

RESUMO

BACKGROUND: Studies have shown that some single nucleotide polymorphisms (SNPs) could serve as excellent markers in foretelling the treatment outcome of interferon (IFN) in myeloproliferative neoplasms (MPN). However, most work originated from western countries, and data from different ethnic populations have been lacking. METHODS: To gain insights, targeted sequencing was performed to detect myeloid-associated mutations and SNPs in eight loci across three genes (IFNL4, IFN-γ, and inosine triphosphate pyrophosphatase [ITPA]) to explore their predictive roles in our cohort of 21 ropeginterferon alpha-2b (ROPEG)-treated MPN patients, among whom real-time quantitative PCR was also performed periodically to monitor the JAK2V617F allele burden in 19 JAK2V617F-mutated cases. RESULTS: ELN response criteria were adopted to designate patients as good responders if they achieved complete hematological responses (CHR) within 1 year (CHR1) or attained major molecular responses (MMR), which occurred in 70% and 45% of the patients, respectively. IFNL4 and IFN-γ gene SNPs were infrequent in our population and were thus excluded from further analysis. Two ITPA SNPs rs6051702 A>C and rs1127354 C>A were associated with an inferior CHR1 rate and MMR rate, respectively. The former seemed to be linked to grade 2 or worse hepatotoxicity as well, although the comparison was of borderline significance only (50%, vs. 6.7% in those with common haplotype, p = 0.053). Twelve patients harbored 19 additional somatic mutations in 12 genes, but the trajectory of these mutations varied considerably and was not predictive of any response. CONCLUSIONS: Overall, this study provided valuable information on the ethnics- and genetics-based algorithm in the treatment of MPN.


Assuntos
Transtornos Mieloproliferativos , Neoplasias , Humanos , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/genética , Resultado do Tratamento , Haplótipos , Células Germinativas , Interferon lambda , Interleucinas/genética
5.
Int J Dev Biol ; 68(1): 9-17, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38591693

RESUMO

The megasporangium serves as a model system for understanding the concept of individual cell identity, and cell-to-cell communication in angiosperms. As development of the ovule progresses, three distinct layers, the epidermal (L1), the subepidermal or the hypodermal (L2) and the innermost layers (L3) are formed along the MMC (megaspore mother cell). The MMC, which is the primary female germline cell, is initiated as a single subepidermal cell amongst several somatic cells. MMC development is governed by various regulatory pathways involving intercellular signaling, small RNAs and DNA methylation. The programming and reprograming of a single nucellar cell to enter meiosis is governed by 'permissive' interacting processes and factors. Concomitantly, several nucellar sister cells are prevented from germline fate also by a set of 'repressive' factors. However, in certain angiosperms, anomalies in development of the female gametophyte have been observed. The sporophytic tissue surrounding the female gametophyte affects the gametophyte in multiple ways. The role of genes and transcription factors in the development of the MMC and in the regulation of various processes studied in selected model plants such as Arabidopsis is explained in detail in this paper. However, as angiosperms display enormous diversity, it is important to investigate early stages of megasporogenesis in other plant systems as well. Such studies provide valuable insights in understanding the regulation of megasporogenesis and the evolution of the female gametophyte from gymnosperms to flowering plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/genética , Gametogênese Vegetal/genética , Óvulo Vegetal/genética , Óvulo Vegetal/metabolismo , Células Germinativas/metabolismo , Regulação da Expressão Gênica de Plantas
6.
BMC Genomics ; 25(1): 344, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580899

RESUMO

BACKGROUND: Genome-wide DNA demethylation occurs in mammalian primordial germ cells (PGCs) as part of the epigenetic reprogramming important for gametogenesis and resetting the epigenetic information for totipotency. Dppa3 (also known as Stella or Pgc7) is highly expressed in mouse PGCs and oocytes and encodes a factor essential for female fertility. It prevents excessive DNA methylation in oocytes and ensures proper gene expression in preimplantation embryos: however, its role in PGCs is largely unexplored. In the present study, we investigated whether or not DPPA3 has an impact on CG methylation/demethylation in mouse PGCs. RESULTS: We show that DPPA3 plays a role in genome-wide demethylation in PGCs even before sex differentiation. Dppa3 knockout female PGCs show aberrant hypermethylation, most predominantly at H3K9me3-marked retrotransposons, which persists up to the fully-grown oocyte stage. DPPA3 works downstream of PRDM14, a master regulator of epigenetic reprogramming in embryonic stem cells and PGCs, and independently of TET1, an enzyme that hydroxylates 5-methylcytosine. CONCLUSIONS: The results suggest that DPPA3 facilitates DNA demethylation through a replication-coupled passive mechanism in PGCs. Our study identifies DPPA3 as a novel epigenetic reprogramming factor in mouse PGCs.


Assuntos
Desmetilação do DNA , Epigênese Genética , Camundongos , Feminino , Animais , Metilação de DNA , Células Germinativas/metabolismo , Genoma , Mamíferos/genética , Proteínas Cromossômicas não Histona/metabolismo
7.
Sci Rep ; 14(1): 7892, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570611

RESUMO

Haplotype-resolved genome assembly plays a crucial role in understanding allele-specific functions. However, obtaining haplotype-resolved assembly for auto-polyploid genomes remains challenging. Existing methods can be classified into reference-based phasing, assembly-based phasing, and gamete binning. Nevertheless, there is a lack of cost-effective and efficient methods for haplotyping auto-polyploid genomes. In this study, we propose a novel phasing algorithm called PolyGH, which combines Hi-C and gametic data. We conducted experiments on tetraploid potato cultivars and divided the method into three steps. Firstly, gametic data was utilized to bin non-collapsed contigs, followed by merging adjacent fragments of the same type within the same contig. Secondly, accurate Hi-C signals related to differential genomic regions were acquired using unique k-mers. Finally, collapsed fragments were assigned to haplotigs based on combined Hi-C and gametic signals. Comparing PolyGH with Hi-C-based and gametic data-based methods, we found that PolyGH exhibited superior performance in haplotyping auto-polyploid genomes when integrating both data types. This approach has the potential to enhance haplotype-resolved assembly for auto-polyploid genomes.


Assuntos
Células Germinativas , Poliploidia , Humanos , Análise de Sequência de DNA/métodos , Haplótipos/genética , Alelos
8.
PLoS One ; 19(4): e0301271, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38573891

RESUMO

OBJECTIVE: To assess the cost-effectiveness and budget impact of olaparib as a maintenance therapy in platinum-responsive, metastatic pancreatic cancer patients harboring a germline BRCA1/2 mutation, using the Swiss context as a model. METHODS: Based on data from the POLO trial, published literature and local cost data, we developed a partitioned survival model of olaparib maintenance including full costs for BRCA1/2 germline testing compared to FOLFIRI maintenance chemotherapy and watch-and-wait. We calculated the incremental cost-effectiveness ratio (ICER) for the base case and several scenario analyses and estimated 5-year budget impact. RESULTS: Comparing olaparib with watch-and wait and maintenance chemotherapy resulted in incremental cost-effectiveness ratios of CHF 2,711,716 and CHF 2,217,083 per QALY gained, respectively. The 5-year costs for the olaparib strategy in Switzerland would be CHF 22.4 million, of which CHF 11.4 million would be accounted for by germline BRCA1/2 screening of the potentially eligible population. This would amount to a budget impact of CHF 15.4 million (USD 16.9 million) versus watch-and-wait. CONCLUSIONS: Olaparib is not a cost-effective maintenance treatment option. Companion diagnostics are an equally important cost driver as the drug itself.


Assuntos
Neoplasias Ovarianas , Neoplasias Pancreáticas , Piperazinas , Feminino , Humanos , Proteína BRCA1/genética , Neoplasias Ovarianas/genética , Platina/uso terapêutico , Proteína BRCA2/genética , Ftalazinas/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Células Germinativas/patologia , Análise Custo-Benefício
9.
Sci Adv ; 10(15): eadg7894, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608012

RESUMO

During Drosophila oogenesis, the Oskar (OSK) RNA binding protein (RBP) determines the amount of germ plasm that assembles at the posterior pole of the oocyte. Here, we identify mechanisms that subsequently regulate germ plasm assembly in the early embryo. We show that the Smaug (SMG) RBP is transported into the germ plasm of the early embryo where it accumulates in the germ granules. SMG binds to and represses translation of the osk messenger RNA (mRNA) as well as the bruno 1 (bru1) mRNA, which encodes an RBP that we show promotes germ plasm production. Loss of SMG or mutation of SMG's binding sites in the osk or bru1 mRNA results in excess translation of these transcripts in the germ plasm, accumulation of excess germ plasm, and budding of excess primordial germ cells (PGCs). Therefore, SMG triggers a posttranscriptional regulatory pathway that attenuates the amount of germ plasm in embryos to modulate the number of PGCs.


Assuntos
Drosophila , Lagartos , Animais , Citoplasma , Células Germinativas , RNA Mensageiro/genética , Contagem de Células
10.
Cancer Res Commun ; 4(4): 1004-1015, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38592450

RESUMO

Asbestos and BAP1 germline mutations are risk factors for malignant mesothelioma (MM). While it is well accepted that amphibole asbestos is carcinogenic, the role of serpentine (chrysotile) asbestos in MM has been debated. To address this controversy, we assessed whether minimal exposure to chrysotile could significantly increase the incidence and rate of MM onset in germline Bap1-mutant mice. With either crocidolite or chrysotile, and at each dose tested, MMs occurred at a significantly higher rate and earlier onset time in Bap1-mutant mice than in wild-type littermates. To explore the role of gene-environment interactions in MMs from Bap1-mutant mice, we investigated proinflammatory and protumorigenic factors and the tumor immune microenvironment (TIME). IHC and immunofluorescence staining showed an increased number of macrophages in granulomatous lesions and MMs. The relative number of CD163-positive (CD163+) M2 macrophages in chrysotile-induced MMs was consistently greater than in crocidolite-induced MMs, suggesting that chrysotile induces a more profound immunosuppressive response that creates favorable conditions for evading immune surveillance. MMs from Bap1-mutant mice showed upregulation of CD39/CD73-adenosine and C-C motif chemokine ligand 2 (Ccl2)/C-C motif chemokine receptor 2 (Ccr2) pathways, which together with upregulation of IL6 and IL10, promoted an immunosuppressive TIME, partly by attracting M2 macrophages. Interrogation of published human MM RNA sequencing (RNA-seq) data implicated these same immunosuppressive pathways and connections with CD163+ M2 macrophages. These findings indicate that increased M2 macrophages, along with upregulated CD39/CD73-adenosine and Ccl2/Ccr2 pathways, contribute to an immunosuppressive TIME in chrysotile-induced MMs of Bap1-mutant mice, suggesting that immunotherapeutic strategies targeting protumorigenic immune pathways could be beneficial in human BAP1 mutation carriers who develop MM. SIGNIFICANCE: We show that germline Bap1-mutant mice have enhanced susceptibility to MM upon minimal exposure to chrysotile asbestos, not only amphibole fibers. Chrysotile induced a more profound immune tumor response than crocidolite in Bap1-mutant mice by upregulating CD39/CD73-adenosine and Ccl2/Ccr2 pathways and recruiting more M2 macrophages, which together contributed to an immunosuppressive tumor microenvironment. Interrogation of human MM RNA-seq data revealed interconnected immunosuppressive pathways consistent with our mouse findings.


Assuntos
Mesotelioma Maligno , Mesotelioma , Neoplasias Mesoteliais , Humanos , Animais , Camundongos , Asbestos Serpentinas , Amiantos Anfibólicos , Asbesto Crocidolita/toxicidade , Microambiente Tumoral/genética , Mesotelioma/induzido quimicamente , Adenosina , Imunossupressores , Células Germinativas
11.
Sci Rep ; 14(1): 8073, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580653

RESUMO

The fishing cat, Prionailurus viverrinus, faces a population decline, increasing the importance of maintaining healthy zoo populations. Unfortunately, zoo-managed individuals currently face a high prevalence of transitional cell carcinoma (TCC), a form of bladder cancer. To investigate the genetics of inherited diseases among captive fishing cats, we present a chromosome-scale assembly, generate the pedigree of the zoo-managed population, reaffirm the close genetic relationship with the Asian leopard cat (Prionailurus bengalensis), and identify 7.4 million single nucleotide variants (SNVs) and 23,432 structural variants (SVs) from whole genome sequencing (WGS) data of healthy and TCC cats. Only BRCA2 was found to have a high recurrent number of missense mutations in fishing cats diagnosed with TCC when compared to inherited human cancer risk variants. These new fishing cat genomic resources will aid conservation efforts to improve their genetic fitness and enhance the comparative study of feline genomes.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Gatos , Animais , Humanos , Genoma/genética , Neoplasias da Bexiga Urinária/patologia , Carcinoma de Células de Transição/patologia , Genômica , Células Germinativas/patologia
12.
JCO Precis Oncol ; 8: e2300355, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38564682

RESUMO

PURPOSE: Pancreatic cancer (PC) is a deadly disease most often diagnosed in late stages. Identification of high-risk subjects could both contribute to preventative measures and help diagnose the disease at earlier timepoints. However, known risk factors, assessed independently, are currently insufficient for accurately stratifying patients. We use large-scale data from the UK Biobank (UKB) to identify genetic variant-smoking interaction effects and show their importance in risk assessment. METHODS: We draw data from 15,086,830 genetic variants and 315,512 individuals in the UKB. There are 765 cases of PC. Crucially, robust resampling corrections are used to overcome well-known challenges in hypothesis testing for interactions. Replication analysis is conducted in two independent cohorts totaling 793 cases and 570 controls. Integration of functional annotation data and construction of polygenic risk scores (PRS) demonstrate the additional insight provided by interaction effects. RESULTS: We identify the genome-wide significant variant rs77196339 on chromosome 2 (per minor allele odds ratio in never-smokers, 2.31 [95% CI, 1.69 to 3.15]; per minor allele odds ratio in ever-smokers, 0.53 [95% CI, 0.30 to 0.91]; P = 3.54 × 10-8) as well as eight other loci with suggestive evidence of interaction effects (P < 5 × 10-6). The rs77196339 region association is validated (P < .05) in the replication sample. PRS incorporating interaction effects show improved discriminatory ability over PRS of main effects alone. CONCLUSION: This study of genome-wide germline variants identified smoking to modify the effect of rs77196339 on PC risk. Interactions between known risk factors can provide critical information for identifying high-risk subjects, given the relative inadequacy of models considering only main effects, as demonstrated in PRS. Further studies are necessary to advance toward comprehensive risk prediction approaches for PC.


Assuntos
Predisposição Genética para Doença , Neoplasias Pancreáticas , Humanos , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Fumar/genética , Fumar/efeitos adversos , Fatores de Risco , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Células Germinativas
13.
Development ; 151(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38546617

RESUMO

Abscission is the final step of cytokinesis that allows the physical separation of sister cells through the scission of the cellular membrane. This deformation is driven by ESCRT-III proteins, which can bind membranes and form dynamic helices. A crucial step in abscission is the recruitment of ESCRT-III proteins at the right time and place. Alix is one of the best characterized proteins that recruits ESCRT-III proteins from yeast to mammals. However, recent studies in vivo have revealed that pathways acting independently or redundantly with Alix are also required at abscission sites in different cellular contexts. Here, we show that Lgd acts redundantly with Alix to properly localize ESCRT-III to the abscission site in germline stem cells (GSCs) during Drosophila oogenesis. We further demonstrate that Lgd is phosphorylated at multiple sites by the CycB/Cdk1 kinase. We found that these phosphorylation events potentiate the activity of Shrub, a Drosophila ESCRT-III, during abscission of GSCs. Our study reveals that redundancy between Lgd and Alix, and coordination with the cell cycle kinase Cdk1, confers robust and timely abscission of Drosophila germline stem cells.


Assuntos
Proteínas de Drosophila , Complexos Endossomais de Distribuição Requeridos para Transporte , Animais , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Proteína Quinase CDC2/genética , Citocinese/genética , Células Germinativas/metabolismo , Drosophila/metabolismo , Células-Tronco , Mamíferos/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Ciclina B
14.
Gan To Kagaku Ryoho ; 51(3): 231-236, 2024 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-38494798

RESUMO

Return of individual genomic results(ROGR)to participants in population-based biobank has been rarely conducted in research settings, and the procedure of ROGR performed in foreign countries may not be simply applied to Japanese participants, because of the difference in social background. The Tohoku Medical Megabank Project, which was launched in 2012 aiming to build a foundation of personalized genomic medicine, obtained the consent from research participants by explaining the future possibility of ROGR. After careful consideration of appropriate procedure for ROGR, individual genomic results were returned to 111 pathogenic variant(PV)carriers of hereditary breast and ovarian cancer syndrome(HBOC)or Lynch syndrome(LS)based on 50,000 whole genome sequencing(WGS)data in FY 2022. Since majority of the participants has no cancer diagnosis, participants' right to not know was carefully considered. In addition, the variants to be returned were carefully evaluated by using multiple databases, and the WGS results of the participants were further confirmed by the single- site analysis. When the genomic results were returned, the participants were informed about clinical risk surveillance at the hospital. Seventy-eight and 33 PV carriers of HBOC and LS, respectively, participated in the study. Most participants were in their 30s or 40s. Unexpectedly, validation testing results of 12 LS participants were found to be negative or variant of uncertain significance, because detecting these variants by WGS were technically challenging. Twenty-eight participants (HBOC 20, LS 8)had been diagnosed as cancer, and 6 females who had breast cancer were genetically diagnosed as HBOC and underwent or planned risk-reducing surgery. Eighteen participants refused to undergo clinical risk surveillance because of the medical expense that is not covered by health insurance and the burden of visiting the hospital. The opportunity to undergo medical surveillance should be provided to population-based cohort participants who carry actionable pathogenic variants, and ROGR to general population should be promoted to create the base of personalized genomic medicine.


Assuntos
Síndrome Hereditária de Câncer de Mama e Ovário , Feminino , Humanos , Estudos de Coortes , Predisposição Genética para Doença , Genômica , Células Germinativas
15.
JCO Precis Oncol ; 8: e2300539, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38484211

RESUMO

PURPOSE: Paired tumor-germline sequencing can identify somatic variants for targeted therapy and germline pathogenic variants (GPVs) causative of hereditary cancer/tumor predisposition syndromes. It is unknown how patients/families in pediatric oncology use information about an identified GPV. We assessed recall of germline results and actions taken on the basis of findings. METHODS: We completed phone surveys with patients (and/or their parent) with GPVs identified via a single academic medical center's paired tumor-germline sequencing study. Seven hundred forty pediatric (aged 0-25 years) oncology patients were enrolled in this sequencing study between May 2012 and August 2021. Ninety-six participants (13.0%) had at least one GPV identified and were therefore eligible for this survey. The parent/guardian (for patients younger than 18 years or deceased patients) or patients themselves (if 18 years or older) were contacted. Survey topics included germline result recall, experience with genetic counseling, changes to patient's cancer treatment/screening, sharing of results with family members, and lifestyle changes. RESULTS: Fifty-three surveys (response rate, 55.2%) were completed between October 2021 and June 2022. Thirty-seven (69.8%) respondents correctly recalled the identified GPV. Discussing results with a genetic counselor (P = .0001), having a GPV related to the cancer/tumor diagnosis (P = .002), and non-Hispanic White race/ethnicity (P = .02) were associated with accurate recall. Twenty-five respondents (47.2%) reported a change in the child's cancer treatment and/or screening recommendations, 17 respondents (32.1%) made a lifestyle change on the basis of the results, and 44 respondents (83.0%) shared results with at least one family member. CONCLUSION: While most respondents remembered that a GPV was identified in the patient, some did not recall having a GPV found, and others recalled germline findings incorrectly. Future work may determine patient/family preferences for timing/method of result return to optimize patient recall and use of germline results.


Assuntos
Predisposição Genética para Doença , Síndromes Neoplásicas Hereditárias , Humanos , Criança , Predisposição Genética para Doença/genética , Oncologia , Mutação em Linhagem Germinativa/genética , Células Germinativas
16.
J Investig Med High Impact Case Rep ; 12: 23247096241240176, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38504422

RESUMO

Gastric cancer ranks as the fifth leading cause of global cancer incidences, exhibiting varied prevalence influenced by geographical, ethnic, and lifestyle factors, as well as Helicobacter pylori infection. The ATM gene on chromosome 11q22 is vital for genomic stability as an initiator of the DNA damage response, and mutations in this gene have been associated with various cancers. Poly ADP-ribose polymerase (PARP) inhibitors, such as olaparib, have shown efficacy in cancers with homologous recombination repair deficiencies, notably in those with ATM mutations. Here, we present a case of a 66-year-old patient with germline ATM-mutated metastatic gastric cancer with very high CA 19-9 (48 000 units/mL) who demonstrated an exceptional response to the addition of olaparib to chemo-immunotherapy and subsequent olaparib maintenance monotherapy for 12 months. CA 19-9 was maintained at low level for 18 months. Despite the failure of a phase II clinical trial on olaparib in gastric cancer (NCT01063517) to meet its primary endpoint, intriguing findings emerged in the subset of ATM-mutated patients, who exhibited notable improvements in overall survival. Our case underscores the potential clinical utility of olaparib in germline ATM-mutated gastric cancer and emphasizes the need for further exploration through larger clinical trials. Ongoing research and clinical trials are essential for optimizing the use of PARP inhibitors, identifying biomarkers, and advancing personalized treatment strategies for gastric cancer.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Ftalazinas , Piperazinas , Neoplasias Gástricas , Humanos , Idoso , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Helicobacter pylori/metabolismo , Células Germinativas/metabolismo , Células Germinativas/patologia , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo
17.
Life Sci Alliance ; 7(6)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38499329

RESUMO

Primordial germ cells (PGCs) are the embryonic precursors of sperm and oocytes, which transmit genetic/epigenetic information across generations. Mouse PGC and subsequent gamete development can be fully reconstituted in vitro, opening up new avenues for germ cell studies in biomedical research. However, PGCs show molecular differences between rodents and humans. Therefore, to establish an in vitro system that is closely related to humans, we studied PGC development in vivo and in vitro in the common marmoset monkey Callithrix jacchus (cj). Gonadal cjPGCs at embryonic day 74 express SOX17, AP2Ɣ, BLIMP1, NANOG, and OCT4A, which is reminiscent of human PGCs. We established transgene-free induced pluripotent stem cell (cjiPSC) lines from foetal and postnatal fibroblasts. These cjiPSCs, cultured in defined and feeder-free conditions, can be differentiated into precursors of mesendoderm and subsequently into cjPGC-like cells (cjPGCLCs) with a transcriptome similar to human PGCs/PGCLCs. Our results not only pave the way for studying PGC development in a non-human primate in vitro under experimentally controlled conditions, but also provide the opportunity to derive functional marmoset gametes in future studies.


Assuntos
Callithrix , Células-Tronco Pluripotentes , Masculino , Camundongos , Animais , Sêmen , Células Germinativas/metabolismo , Células-Tronco Embrionárias/metabolismo
18.
Neuropathol Appl Neurobiol ; 50(2): e12970, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38504418

RESUMO

PTEN hamartoma tumour syndrome (PHTS) comprises different hereditary conditions caused by germline PTEN mutations, predisposing to the development of multiple hamartomas in many body tissues and also increasing the risk of some types of cancer. Cerebellar involvement in PHTS patients has been long known due to the development of a pathognomonic cerebellar hamartoma (known as dysplastic gangliocytoma of the cerebellum or Lhermitte-Duclos disease). Recently, a crucial role of the cerebellum has been highlighted in the pathogenesis of autism spectrum disorders, now recognised as a phenotype expressed in a variable percentage of PHTS children. In addition, rare PTEN variants are indeed identified in medulloblastoma as well, even if they are less frequent than other germline gene mutations. The importance of PTEN and its downstream signalling enzymatic pathways, PI3K/AKT/mTOR, has been studied at different levels in both human clinical settings and animal models, not only leading to a better understanding of the pathogenesis of different disorders but, most importantly, to identify potential targets for specific therapies. In particular, PTEN integrity makes an important contribution to the normal development of tissue architecture in the nervous system, including the cerebellum. Thus, in patients with PTEN germline mutations, the cerebellum is an affected organ that is increasingly recognised in different disorders, whereas, in animal models, cerebellar Pten loss causes a variety of functional and histological alterations. In this review, we summarise the range of cerebellar involvement observed in PHTS and its relationships with germline PTEN mutations, along with the phenotypes expressed by murine models with PTEN deficiency in cerebellar tissue.


Assuntos
Neoplasias Cerebelares , Síndrome do Hamartoma Múltiplo , Criança , Humanos , Animais , Camundongos , Mutação em Linhagem Germinativa , Fosfatidilinositol 3-Quinases , PTEN Fosfo-Hidrolase/genética , Cerebelo/patologia , Síndrome do Hamartoma Múltiplo/genética , Síndrome do Hamartoma Múltiplo/patologia , Fenótipo , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/patologia , Células Germinativas/patologia , Mutação
19.
Proc Natl Acad Sci U S A ; 121(11): e2316118121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38442152

RESUMO

Retinitis pigmentosa (RP) is a common form of retinal dystrophy that can be caused by mutations in any one of dozens of rod photoreceptor genes. The genetic heterogeneity of RP represents a significant challenge for the development of effective therapies. Here, we present evidence for a potential gene-independent therapeutic strategy based on targeting Nr2e3, a transcription factor required for the normal differentiation of rod photoreceptors. Nr2e3 knockout results in hybrid rod photoreceptors that express the full complement of rod genes, but also a subset of cone genes. We show that germline deletion of Nr2e3 potently protects rods in three mechanistically diverse mouse models of retinal degeneration caused by bright-light exposure (light damage), structural deficiency (rhodopsin-deficient Rho-/- mice), or abnormal phototransduction (phosphodiesterase-deficient rd10 mice). Nr2e3 knockout confers strong neuroprotective effects on rods without adverse effects on their gene expression, structure, or function. Furthermore, in all three degeneration models, prolongation of rod survival by Nr2e3 knockout leads to lasting preservation of cone morphology and function. These findings raise the possibility that upregulation of one or more cone genes in Nr2e3-deficient rods may be responsible for the neuroprotective effects we observe.


Assuntos
Fármacos Neuroprotetores , Distrofias Retinianas , Retinite Pigmentosa , Animais , Camundongos , Células Fotorreceptoras Retinianas Cones , Retinite Pigmentosa/genética , Modelos Animais de Doenças , Células Germinativas , Receptores Nucleares Órfãos
20.
JCO Precis Oncol ; 8: e2300552, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38452310

RESUMO

PURPOSE: Germline genetic testing (GT) is important for prostate cancer (PCA) management, clinical trial eligibility, and hereditary cancer risk. However, GT is underutilized and there is a shortage of genetic counselors. To address these gaps, a patient-driven, pretest genetic education webtool was designed and studied compared with traditional genetic counseling (GC) to inform strategies for expanding access to genetic services. METHODS: Technology-enhanced acceleration of germline evaluation for therapy (TARGET) was a multicenter, noninferiority, randomized trial (ClinicalTrials.gov identifier: NCT04447703) comparing a nine-module patient-driven genetic education webtool versus pretest GC. Participants completed surveys measuring decisional conflict, satisfaction, and attitudes toward GT at baseline, after pretest education/counseling, and after GT result disclosure. The primary end point was noninferiority in reducing decisional conflict between webtool and GC using the validated Decisional Conflict Scale. Mixed-effects regression modeling was used to compare decisional conflict between groups. Participants opting for GT received a 51-gene panel, with results delivered to participants and their providers. RESULTS: The analytic data set includes primary outcome data from 315 participants (GC [n = 162] and webtool [n = 153]). Mean difference in decisional conflict score changes between groups was -0.04 (one-sided 95% CI, -∞ to 2.54; P = .01), suggesting the patient-driven webtool was noninferior to GC. Overall, 145 (89.5%) GC and 120 (78.4%) in the webtool arm underwent GT, with pathogenic variants in 15.8% (8.7% in PCA genes). Satisfaction did not differ significantly between arms; knowledge of cancer genetics was higher but attitudes toward GT were less favorable in the webtool arm. CONCLUSION: The results of the TARGET study support the use of patient-driven digital webtools for expanding access to pretest genetic education for PCA GT. Further studies to optimize patient experience and evaluate them in diverse patient populations are warranted.


Assuntos
Aconselhamento Genético , Neoplasias da Próstata , Humanos , Masculino , Aconselhamento Genético/métodos , Testes Genéticos , Células Germinativas , Conhecimentos, Atitudes e Prática em Saúde , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/terapia
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