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1.
Planta ; 259(2): 39, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38265504

RESUMO

MAIN CONCLUSION: The nuclear localized TaWZY1-2 helps plants resist abiotic stress by preserving the cell's ability to remove reactive oxygen species and decrease lipid oxidation under such conditions. In light of the unpredictable environmental conditions in which food crops grow, precise strategies must be developed by crops to effectively cope with abiotic stress and minimize damage over their lifespan. A key component in this endeavor is the group II of late embryogenesis abundant (LEA) proteins, known as dehydrins, which play crucial roles in enhancing the tolerance of plants to abiotic stress. Tawzy1-2 is a dehydrin-encoding gene which is constitutively expressed in various tissues of wheat. However, the biological function of TaWZY1-2 is not yet fully understood. In this study, TaWZY1-2 was isolated and identified in the wheat genome, and its functional role in conferring tolerance to abiotic stresses was detected in both prokaryotic and eukaryotic cells. Results showed that TaWZY1-2 is a nuclear localized hydrophilic protein that accumulates in response to multiple stresses. Escherichia coli cells expressing TaWZY1-2 showed enhanced tolerance to multiple stress conditions. Overexpression of TaWZY1-2 in Nicotiania benthamiana improved growth, germination and survival rate of the transgenic plants exposed to four kinds of abiotic stress conditions. Our results show that Tawzy1-2 transgenic plants exhibit improved capability in clearing reactive oxygen species and reducing lipid degradation, thereby enhancing their resistance to abiotic stress. This demonstrates a significant role of TaWZY1-2 in mitigating abiotic stress-induced damage. Consequently, these findings not only establish a basis for future investigation into the functional mechanism of TaWZY1-2 but also contribute to the expansion of functional diversity within the dehydrin protein family. Moreover, they identify potential candidate genes for crop optimization.


Assuntos
Produtos Agrícolas , Escherichia coli , Nicotiana , Lipídeos , Proteínas Nucleares , Plantas Geneticamente Modificadas , Espécies Reativas de Oxigênio , Estresse Fisiológico
2.
Mol Biol Rep ; 50(7): 5777-5789, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37219670

RESUMO

BACKGROUND: Promoters play key roles in plant gene expression in complex and varied natural environments. The type and amount of cis-acting elements in the promoter sequence tend to indicate the response of genes to induction factors. WRAB18 is a group III member of the late embryogenesis abundant (LEA) protein family that performs multiple functions in plant stress physiology. To elucidate the particularly biological effects of WRAB18 on stress, exploration of its promoter sequence is necessary. METHODS AND RESULTS: In this study, the full-length and promoter sequences of Wrab18 were isolated from the Zhengyin 1 cultivar of Triticum aestivum. The gene sequences and cis-acting elements in the promoter were analyzed using the Plant Promoter Database and bioinformatics methods. The results showed that Wrab18 possessed one intron with 100 bp, the promoter sequence contained various stress-related cis-acting elements, and the functionality of the promoter was checked using green fluorescent protein (GFP) marker protein expression by transient assay in Nicotiana benthamiana. Furthermore, based on promoter prediction analysis, quantitative real-time fluorescent PCR results confirmed the response of gene expression levels to stress factors. CONCLUSIONS: In summary, the promoter sequence of Wrab18 plays a role in plant stress responses, contains multiple cis-acting elements, and provides insights into the role of WRAB18 in plant resilience to stress. This study has guiding significance for further studies of gene function and mechanism of action, and lays a theoretical foundation for improving wheat quality.


Assuntos
Proteínas de Plantas , Triticum , Triticum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Genes de Plantas , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas/genética , Filogenia
3.
Parasitol Res ; 122(5): 1107-1126, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36933066

RESUMO

The identification of additional Echinococcus granulosus sensu lato (s.l.) complex species/genotypes in recent years raises the possibility that there might be more variation among this species in China than is currently understood. The aim of this study was to explore intra- and inter-species variation and population structure of Echinococcus species isolated from sheep in three areas of Western China. Of the isolates, 317, 322, and 326 were successfully amplified and sequenced for cox1, nad1, and nad5 genes, respectively. BLAST analysis revealed that the majority of the isolates were E. granulosus s.s., and using the cox1, nad1, and nad5 genes, respectively, 17, 14, and 11 isolates corresponded to Elodea canadensis (genotype G6/G7). In the three study areas, G1 genotypes were the most prevalent. There were 233 mutation sites along with 129 parsimony informative sites. A transition/transversion ratio of 7.5, 8, and 3.25, respectively, for cox1, nad1, and nad5 genes was obtained. Every mitochondrial gene had intraspecific variations, which were represented in a star-like network with a major haplotype with observable mutations from other distant and minor haplotypes. The Tajima's D value was significantly negative in all populations, indicating a substantial divergence from neutrality and supporting the demographic expansion of E. granulosus s.s. in the study areas. The phylogeny inferred by the maximum likelihood (ML) method using nucleotide sequences of cox1-nad1-nad5 further confirmed their identity. The nodes assigned to the G1, G3, and G6 clades as well as the reference sequences utilized had maximal posterior probability values (1.00). In conclusion, our study confirms the existence of a significant major haplotype of E. granulosus s.s. where G1 is the predominant genotype causing of CE in both livestock and humans in China.


Assuntos
Equinococose , Echinococcus granulosus , Animais , Humanos , Ovinos , Echinococcus granulosus/genética , Tibet , Equinococose/epidemiologia , Equinococose/veterinária , China , Genótipo , Haplótipos , Mutação , Filogenia , Variação Genética
4.
J Biol Chem ; 297(6): 101357, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34756887

RESUMO

It has been shown that phages have evolved anti-CRISPR (Acr) proteins to inhibit host CRISPR-Cas systems. Most acr genes are located upstream of anti-CRISPR-associated (aca) genes, which is instrumental for identifying these acr genes. Thus far, eight Aca families (Aca1-Aca8) have been identified, all proteins of which share low sequence homology and bind to different target DNA sequences. Recently, Aca1 and Aca2 proteins were discovered to function as repressors by binding to acr-aca promoters, thus implying a potential anti-anti-CRISPR mechanism. However, the structural basis for the repression roles of Aca proteins is still unknown. Here, we elucidated apo-structures of Aca1 and Aca2 proteins and their complex structures with their cognate operator DNA in two model systems, the Pseudomonas phage JBD30 and the Pectobacterium carotovorum template phage ZF40. In combination with biochemical and cellular assays, our study unveils dimerization and DNA-recognition mechanisms of Aca1 and Aca2 family proteins, thus revealing the molecular basis for Aca1-and Aca2-mediated anti-CRISPR repression. Our results also shed light on understanding the repression roles of other Aca family proteins and autoregulation roles of acr-aca operons.


Assuntos
Bacteriófagos/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Óperon , Pectobacterium carotovorum/virologia , Pseudomonas aeruginosa/virologia , Proteínas Virais/metabolismo , Bacteriófagos/química , Bacteriófagos/genética , Modelos Moleculares , Pectobacterium carotovorum/genética , Pectobacterium carotovorum/metabolismo , Conformação Proteica , Multimerização Proteica , Fagos de Pseudomonas/química , Fagos de Pseudomonas/genética , Fagos de Pseudomonas/metabolismo , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Proteínas Virais/química , Proteínas Virais/genética
5.
Langmuir ; 38(39): 11873-11881, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36125335

RESUMO

A comprehensive understanding of the slip phenomenon on liquid/solid interfaces is essential for multiple real-world applications of superhydrophobic materials, especially those involving drag reduction. In the current contribution, the so-called "slip-length" on an irregularly structured superhydrophobic surface was systematically evaluated, with respect to varying liquid surface tension and viscosity. The superhydrophobic polymer-nanoparticle composite (SPNC) material used exhibits a dual-scale surface roughness and was fabricated via coating a surface with a mixture of polydimethylsiloxane solution and functionalized silica particles. A cone-and-plate rheometric device was employed to quantify the slip length. To independently study the impact of surface tension and viscosity, three types of aqueous solutions were used: sodium dodecyl sulfate, ethanol, and polyethylene glycol. Our experimental results demonstrate that a decreasing surface tension results in a decreasing slip length when the fluid viscosity is held constant. Meanwhile, the slip length is shown to increase with increasing viscosity when the surface tension of the various liquids is matched to isolate effects. The study reveals a linear relationship between slip length and both capillary length and viscosity providing a reference to potentially predict the degree of achievable drag reduction for differing fluids on SPNC surfaces.

6.
Parasitol Res ; 121(12): 3455-3466, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36149499

RESUMO

Parasitic infection is one of the many challenges facing livestock production globally. Cysticercosis tenuicollis is a common parasitic disease in domestic and wild ruminants (intermediate host) caused by the larval stage of Taenia hydatigena that primarily infects dogs (definitive host). Although genetic studies on this parasite exist, only a few describe the genetic variation of this parasite in Mongolia. Our aim was thus, to identify the mitochondrial differences in ovine isolates of Cysticercus tenuicollis entering China from Mongolia and comparison with existing Chinese isolates from sheep and goats based on the recently described PCR-RFLP method and mitochondrial genes of NADH dehydrogenase subunit 4 (nad4) and the NADH dehydrogenase subunit 5 (nad5). Sixty-nine isolates were collected during routine veterinary meat inspections from sheep that originated from Mongolia, at the modern slaughterhouses in Erenhot City, Inner Mongolia. Additional 114 cysticerci were also retrieved from sheep and goats from northern (Inner Mongolia Autonomous Region, Ningxia Hui Autonomous Region, and Gansu Province), western (Tibet Autonomous Region), and southern (Jiangxi Province and Guangxi Province) China. The PCR-RFLP approach of the nad5 showed nine mitochondrial subclusters A1, A2, A3, A5, A8, A9, A10, A11, and B of T. hydatigena isolates from sheep and goats from Mongolia and China. Meanwhile, haplogroup A1 RFLP profile was more widespread than other variants. These data supplements existing information on the molecular epidemiology of T. hydatigena in China and Mongolia and demonstrate the occurrence of similar genetic population structures in both countries.


Assuntos
Cisticercose , Doenças dos Ovinos , Taenia , Ovinos , Animais , Cães , Taenia/genética , Cysticercus/genética , Mongólia/epidemiologia , Variação Genética , Filogenia , China , Cisticercose/epidemiologia , Cisticercose/veterinária , Cisticercose/parasitologia , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Cabras
7.
Parasitology ; 148(7): 879-886, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33757604

RESUMO

Echinococcus shiquicus is currently limited to the Qinghai­Tibet plateau, a large mountainous region in China. Although the zoonotic potential remains unknown, progress is being made on the distribution and intermediate host range. In this study, we report E. shiquicus within Gansu and Qinghai provinces in regions located not only around the central areas but also the southeast edge of the plateau and describe their genetic relationship with previous isolates from the plateau. From 1879 plateau pikas examined, 2.39% (95% CI 1.79­3.18) were infected with E. shiquicus. The highest prevalence of 10.26% (4.06­23.58) was recorded in Makehe town, Qinghai province. Overall the prevalence was marginally higher in Qinghai (2.5%, CI 1.82­3.43) than in Gansu (2%, CI 1.02­3.89). The cox1 and nad1 genes demonstrated high and low haplotype and nucleotide diversities, respectively. The median-joining network constructed by the cox1­nad1 gene sequences demonstrated a star-like configuration with a median vector (unsampled haplotype) occupying the centre of the network. No peculiar distinction or common haplotype was observed in isolates originating from the different provinces. The presence of E. shiquicus in regions of the southeast and northeast edges of the Qinghai­Tibet plateau and high genetic variation warrants more investigation into the haplotype distribution and genetic polymorphism by exploring more informative DNA regions of the mitochondrial genome to provide epidemiologically useful insight into the population structure of E. shiquicus across the plateau and its axis.


Assuntos
Distribuição Animal , Equinococose/veterinária , Echinococcus/isolamento & purificação , Lagomorpha , Animais , Equinococose/epidemiologia , Equinococose/parasitologia , Dinâmica Populacional , Prevalência , Tibet
8.
J Cutan Pathol ; 48(2): 302-308, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32592167

RESUMO

Primary cutaneous Ewing sarcoma is a very rare entity with less than 100 cases reported in the literature, sharing the same morphological and immunohistochemical characteristics as their osseous counterparts. Herein, to the best of our knowledge, we report the first case in English literature of a molecularly confirmed Ewing sarcoma with diffuse and strong SOX10 immunoreactivity. This exceedingly rare immunohistochemical finding along with the rarity of this tumor could easily lead to a misdiagnosis with significant repercussions. Our case highlights the difficulty in diagnosing primary cutaneous Ewing sarcoma as well as the pivotal role molecular diagnostics can play in specific scenarios.


Assuntos
Proteínas de Neoplasias/metabolismo , Fatores de Transcrição SOXE/metabolismo , Sarcoma de Ewing , Neoplasias Cutâneas , Adulto , Humanos , Masculino , Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/metabolismo , Sarcoma de Ewing/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
9.
BMC Plant Biol ; 20(1): 259, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503498

RESUMO

BACKGROUND: As functional proteins, dehydrins are found in many maturing seeds and vegetable tissues under adverse environmental conditions. However, the regulation of dehydrin expression remains unclear. RESULTS: In this study, a novel drought stress-related bHLH transcription factor, TabHLH49, was isolated from a wheat cDNA library treated with the drought and cold stress by using yeast one-hybrid system. TabHLH49 protein possesses a typical conserved bHLH domain and is a Myc-type bHLH transcription factor. TabHLH49 was detected in the nucleus of tobacco epidermal cells, and the amino acid sequences at the C-terminus (amino acids 323-362) is necessary for its transactivation activity. Real-time PCR analyses revealed the tissue-specific expression and drought stress-responsive expression of TabHLH49 in wheat. In addition, the verification in Y1H and electrophoretic mobility shift assays illustrated that TabHLH49 protein can bind and interact with the promoter of the wheat WZY2 dehydrin. Furthermore, the dual-luciferase assays showed that TabHLH49 can positively regulate the expression of WZY2 dehydrin. The transient expression and BSMV-mediated gene silencing of TabHLH49 also showed that TabHLH49 positively regulates the expression of WZY2 dehydrin and improves drought stress resistance in wheat. CONCLUSIONS: These results provide direct evidences that TabHLH49 positively regulates expression level of dehydrin WZY2 gene and improves drought tolerance of wheat.


Assuntos
Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Triticum/metabolismo , Clorofila/metabolismo , Desidratação , Regulação da Expressão Gênica de Plantas , Malondialdeído/metabolismo , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Transcrição/genética , Transcriptoma , Triticum/genética , Triticum/fisiologia , Técnicas do Sistema de Duplo-Híbrido
10.
Oncologist ; 23(10): 1127-1132, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29739898

RESUMO

With the advent of precision medicine, medical oncology is undergoing a transcendental change. These molecular studies have allowed us to learn about potential targeted therapies for patients with advanced cancers. Perhaps the best-known example of success in precision medicine is chronic myeloid leukemia and its response to tyrosine kinase inhibitors targeting the BCR-ABL kinase. Since that original discovery, the role of molecular therapeutics has expanded, and it now presents us with treatment options for common malignancies and rare atypical tumors. In this article, we present a case of a 61-year-old female with a recurrent pulmonary inflammatory myofibroblastic tumor. Subsequent molecular studies revealed an ALK rearrangement. The significance of this alteration in this tumor type and its therapeutic implications are discussed herein. KEY POINTS: This case exemplifies the heterogeneous behavior of inflammatory myofibroblastic tumors (IMTs) and the current role of targeted therapy in the therapeutic armamentarium of neoplastic processes.As evidenced by the different mutations found in IMTs, it is of great importance to perform next-generation sequencing in uncommon neoplasms.These studies can find different potential targets and therapeutic options for patients devoid of standard effective therapies.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias de Tecido Muscular/genética , Proteínas de Fusão Oncogênica/genética , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias de Tecido Muscular/metabolismo , Neoplasias de Tecido Muscular/patologia
12.
J Cutan Pathol ; 45(12): 933-939, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30175468

RESUMO

A subset of soft tissue sarcomas often harbors recurrent fusions involving protein kinases. While some of these fusion events have shown utility in arriving at a precise diagnosis, novel fusions in otherwise difficult to classify sarcomas continue to be identified. We present a case of a 40-year-old female who noted a lower back nodule in 2010 that was initially labeled as a dermatofibrosarcoma protuberans with fibrosarcomatous transformation. The lesion recurred the following year and metastasized to the groin 6 years later. Because of some morphologic peculiarities, molecular characterization was pursued in the metastatic focus, which revealed the neoplasm was negative for the COL1A1-PDGFB fusion. However, anchored multiplex polymerase chain reaction for targeted next-generation sequencing (Archer Dx) detected an EML4-NTRK3 fusion, which was confirmed by reverse transcription-PCR, Sanger sequencing and RNA sequencing analysis of the recurrent and metastatic specimens. Although various soft tissue neoplasms involving fusions with NTRK genes are well-reported, the current case could not be easily classified in any of the established entities. Nevertheless, it raises interesting questions regarding the importance of classification, prognosis, and treatment for some of these tyrosine kinase fusion-driven sarcomas.


Assuntos
Proteínas de Ciclo Celular , Dermatofibrossarcoma , Receptor com Domínio Discoidina 2 , Proteínas Associadas aos Microtúbulos , Proteínas de Fusão Oncogênica , Serina Endopeptidases , Neoplasias Cutâneas , Adulto , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Dermatofibrossarcoma/genética , Dermatofibrossarcoma/metabolismo , Dermatofibrossarcoma/patologia , Receptor com Domínio Discoidina 2/genética , Receptor com Domínio Discoidina 2/metabolismo , Feminino , Humanos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
13.
Int J Mol Sci ; 19(11)2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-30384475

RESUMO

Abiotic stress affects the growth and development of crops tremendously, worldwide. To avoid adverse environmental effects, plants have evolved various efficient mechanisms to respond and adapt to harsh environmental factors. Stress conditions are associated with coordinated changes in gene expressions at a transcriptional level. Dehydrins have been extensively studied as protectors in plant cells, owing to their vital roles in sustaining the integrity of membranes and lactate dehydrogenase (LDH). Dehydrins are highly hydrophilic and thermostable intrinsically disordered proteins (IDPs), with at least one Lys-rich K-segment. Many dehydrins are induced by multiple stress factors, such as drought, salt, extreme temperatures, etc. This article reviews the role of dehydrins under abiotic stress, regulatory networks of dehydrin genes, and the physiological functions of dehydrins. Advances in our understanding of dehydrin structures, gene regulation and their close relationships with abiotic stresses demonstrates their remarkable ability to enhance stress tolerance in plants.


Assuntos
Membrana Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Estresse Fisiológico , Membrana Celular/genética , Proteínas de Plantas/genética , Plantas/genética
14.
Funct Integr Genomics ; 14(1): 111-25, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24363037

RESUMO

Dehydrins (DHNs), which are stress-related proteins, are important for plant survival under various abiotic and biotic stresses. To elucidate the regulatory mechanisms of wheat-derived DHNs under these stresses, we characterized the DHN wzy2 promoter of the wheat cultivar Zhengyin 1 and studied its contribution to stress tolerance. Sequence analysis indicated that the wzy2 gene contains one 109-bp intron inserted in the nucleotide sequence encoding the S-motif and characterized by a GT-AG border. The wzy2 promoter was revealed to contain several potential stress-related cis-acting regulatory elements, including elements responsive to abscisic acid (ABA; ABREs), anoxia (GC motifs), low temperature (LTREs), auxin (TGA elements), methyl jasmonate (MeJA; TGACG motifs), and gibberellin (TATC boxes). Quantitative real-time PCR analysis showed that transcript accumulation occurred in response to low temperature, anoxia, indoleacetic acid, MeJA, ABA, and gibberellin (GA) treatments. Histochemical analysis of GUS expression demonstrated that wzy2 promoter activity could be upregulated by low temperature, anoxia, ABA, and GA treatments. Interestingly, wzy2 promoter element-driven ß-glucuronidase expression was first observed in meristemoids rather than calli of wheat seeds subjected to anoxia. Taken together, these results indicate that YSK2-type wzy2 can be induced directly by ABA, low temperature, anoxia, and GA treatments and indirectly by drought, implying that different cis-acting elements interact in stress response cross talk.


Assuntos
Triticum , Triticum/genética
15.
Lab Med ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001691

RESUMO

Genetic alterations that affect the function of p53 tumor suppressor have been extensively investigated in myeloid neoplasms, revealing their significant impact on disease progression, treatment response, and patient outcomes. The identification and characterization of TP53 mutations play pivotal roles in subclassifying myeloid neoplasms and guiding treatment decisions. Starting with the presentation of a typical case, this review highlights the complicated nature of genetic alterations involving TP53 and provides a comprehensive analysis of TP53 mutations and other alterations in myeloid neoplasms. Currently available methods used in clinical laboratories to identify TP53 mutations are discussed, focusing on the importance of establishing a robust testing protocol within clinical laboratories to ensure the delivery of accurate and reliable results. The treatment implications of TP53 mutations in myeloid neoplasms and clinical trial options are reviewed. Ultimately, we hope that this review provides valuable insights into the patterns of TP53 alterations in myeloid neoplasms and offers guidance to establish practical laboratory testing protocols to support the best practices of precision oncology.

16.
Cancers (Basel) ; 16(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38339265

RESUMO

Myelofibrosis (MF) is an essential element of primary myelofibrosis, whereas secondary MF may develop in the advanced stages of other myeloid neoplasms, especially polycythemia vera and essential thrombocythemia. Over the last two decades, advances in molecular diagnostic techniques, particularly the integration of next-generation sequencing in clinical laboratories, have revolutionized the diagnosis, classification, and clinical decision making of myelofibrosis. Driver mutations involving JAK2, CALR, and MPL induce hyperactivity in the JAK-STAT signaling pathway, which plays a central role in cell survival and proliferation. Approximately 80% of myelofibrosis cases harbor additional mutations, frequently in the genes responsible for epigenetic regulation and RNA splicing. Detecting these mutations is crucial for diagnosing myeloproliferative neoplasms (MPNs), especially in cases where no mutations are present in the three driver genes (triple-negative MPNs). While fibrosis in the bone marrow results from the disturbance of inflammatory cytokines, it is fundamentally associated with mutation-driven hematopoiesis. The mutation profile and order of acquiring diverse mutations influence the MPN phenotype. Mutation profiling reveals clonal diversity in MF, offering insights into the clonal evolution of neoplastic progression. Prognostic prediction plays a pivotal role in guiding the treatment of myelofibrosis. Mutation profiles and cytogenetic abnormalities have been integrated into advanced prognostic scoring systems and personalized risk stratification for MF. Presently, JAK inhibitors are part of the standard of care for MF, with newer generations developed for enhanced efficacy and reduced adverse effects. However, only a minority of patients have achieved a significant molecular-level response. Clinical trials exploring innovative approaches, such as combining hypomethylation agents that target epigenetic regulators, drugs proven effective in myelodysplastic syndrome, or immune and inflammatory modulators with JAK inhibitors, have demonstrated promising results. These combinations may be more effective in patients with high-risk mutations and complex mutation profiles. Expanding mutation profiling studies with more sensitive and specific molecular methods, as well as sequencing a broader spectrum of genes in clinical patients, may reveal molecular mechanisms in cases currently lacking detectable driver mutations, provide a better understanding of the association between genetic alterations and clinical phenotypes, and offer valuable information to advance personalized treatment protocols to improve long-term survival and eradicate mutant clones with the hope of curing MF.

17.
Hematol Rep ; 16(2): 308-316, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38921179

RESUMO

EBV-positive nodal T- and NK-cell lymphoma (EBV+ NT/NKCL) is a recently recognized entity in the 5th edition of the WHO Classification of Tumors of Hematopoietic and Lymphoid Tissues. Notably, CD30 positivity is frequently observed in (EBV+ NT/NKCL), creating diagnostic challenges to distinguish it from ALK-negative anaplastic large cell lymphoma (ALCL). Furthermore, cases of EBV+ ALCL have been documented in the literature, predating the inclusion of EBV+ nodal cytotoxic T-cell lymphoma as a variant of peripheral T-cell lymphoma. We present a case of a 47-year-old male presenting with multiple lymphadenopathies. The histomorphologic and immunophenotypic features of the lymph node closely resemble ALK-negative ALCL, characterized by uniform CD30 expression and a subcapsular distribution of lymphoma cells. However, the lymphoma cells exhibit diffuse positivity for EBV, consistent with EBV+ NT/NKCL. A case of ALK-negative ALCL with an immunophenotype identical to the EBV-positive case is included for comparison. Given that EBV+ NT/NKCL represents an aggressive neoplasm requiring unique clinical management compared to ALK-negative ALCL, it is critical to accurately differentiate EBV+ NT/NKCL from ALK-negative ALCL with a cytotoxic T-cell immunophenotype.

18.
Cancers (Basel) ; 16(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38672585

RESUMO

Myelodysplastic Neoplasms (MDS) have been traditionally studied through the assessment of blood counts, cytogenetics, and morphology. In recent years, the introduction of molecular assays has improved our ability to diagnose MDS. The role of Measurable (minimal) Residual Disease (MRD) in MDS is evolving, and molecular and flow cytometry techniques have been used in several studies. In this review, we will highlight the evolving concept of MRD in MDS, outline the various techniques utilized, and provide an overview of the studies reporting MRD and the correlation with outcomes.

19.
CNS Oncol ; 13(1): 2357535, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38864818

RESUMO

Primary effusion lymphoma (PEL) is an uncommon B-cell lymphoma associated with human herpesvirus 8 and comprises 3-4% of all HIV-related lymphomas. It traditionally presents as a pleural, pericardial, and/or peritoneal effusion, though it can occasionally manifest as an extracavitary or solid mass in the absence of an effusion. The extracavitary or solid variant of primary effusion lymphoma has been reported in the skin, gastrointestinal tract, lung, and lymph nodes. However, very few cases have been reported in the central nervous system. We describe a case of extracavitary or solid variant of primary effusion lymphoma presenting as a brain mass in an HIV-positive man, highlighting the clinicopathologic and immunophenotypic findings of a rare entity.


Primary effusion lymphoma (PEL) is an uncommon and aggressive form of large B-cell lymphoma with a grim outlook, making up less than 1% of all lymphomas. PEL is linked to human herpesvirus 8 and predominantly impacts individuals with HIV or weakened immune systems. The typical presentation of PEL involves cancerous fluid accumulating in the chest or abdominal cavities. Occasionally, PEL can appear as a solid mass outside these cavities, termed extracavitary PEL (EC-PEL). The case we are describing highlights the difficulties in diagnosing PEL/EC-PEL. It is crucial for healthcare providers to consider EC-PEL when dealing with human herpesvirus 8-positive B-cell lymphomas, especially when patients have weakened immune systems and an unusual clinical scenario involving a solid mass, as seen in this case.


Assuntos
Neoplasias Encefálicas , Linfoma de Efusão Primária , Humanos , Linfoma de Efusão Primária/patologia , Linfoma de Efusão Primária/diagnóstico , Masculino , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico , Pessoa de Meia-Idade
20.
Arch Pathol Lab Med ; 148(3): 310-317, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37327205

RESUMO

CONTEXT.­: Genetic profiling data of prostatic adenocarcinoma are derived from predominantly White patients. In African Americans, prostatic adenocarcinoma has a poorer prognosis, raising the possibility of distinct genetic alterations. OBJECTIVE.­: To investigate the genomic alterations of prostatic adenocarcinoma metastatic to regional lymph nodes in African American patients, with an emphasis on SPOP mutation. DESIGN.­: We retrospectively reviewed African American patients with pN1 prostatic adenocarcinoma managed with radical prostatectomy and lymph node dissection. Comprehensive molecular profiling was performed, and androgen receptor signaling scores were calculated. RESULTS.­: Nineteen patients were included. The most frequent genetic alteration was SPOP mutations (5 of 17; 29.4% [95% CI: 10.3-56.0]). While most alterations were associated with a high androgen receptor signaling score, mutant SPOP was exclusively associated with a low median and interquartile range (IQR) androgen receptor signaling score (0.788 [IQR 0.765-0.791] versus 0.835 [IQR 0.828-0.842], P = .003). In mutant SPOP, mRNA expression of SPOP inhibitor G3BP1 and SPOP substrates showed a significantly decreased expression of AR (33.40 [IQR 28.45-36.30] versus 59.53 [IQR 53.10-72.83], P = .01), TRIM24 (3.95 [IQR 3.28-5.03] versus 9.80 [IQR 7.39-11.70], P = .008), and NCOA3 (15.19 [IQR 10.59-15.93] versus 21.88 [IQR 18.41-28.33], P = .046). CONCLUSIONS.­: African American patients with metastatic prostate adenocarcinoma might have a higher prevalence of mutant SPOP (30%), compared to ∼10% in unselected cohorts with lower expressions of SPOP substrates. In our study, in patients with mutant SPOP, the mutation was associated with decreased SPOP substrate expression and androgen receptor signaling, raising concern for suboptimal efficacy of androgen deprivation therapy in this subset of patients.


Assuntos
Adenocarcinoma , Proteínas de Transporte , Neoplasias da Próstata , Humanos , Masculino , Adenocarcinoma/genética , Adenocarcinoma/patologia , Antagonistas de Androgênios , Negro ou Afro-Americano/genética , DNA Helicases , Linfonodos/patologia , Proteínas Nucleares/genética , Projetos Piloto , Proteínas de Ligação a Poli-ADP-Ribose , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Receptores Androgênicos/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Estudos Retrospectivos , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA
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