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1.
Proc Natl Acad Sci U S A ; 121(41): e2321378121, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39352925

RESUMO

Progerin causes Hutchinson-Gilford progeria syndrome (HGPS), but how progerin accelerates aging is still an interesting question. Here, we provide evidence linking nuclear envelope (NE) budding and accelerated aging. Mechanistically, progerin disrupts nuclear lamina to induce NE budding in concert with lamin A/C, resulting in transport of chromatin into the cytoplasm where it is removed via autophagy, whereas emerin antagonizes this process. Primary cells from both HGPS patients and mouse models express progerin and display NE budding and chromatin loss, and ectopically expressing progerin in cells can mimic this process. More excitingly, we screen a NE budding inhibitor chaetocin by high-throughput screening, which can dramatically sequester progerin from the NE and prevent this NE budding through sustaining ERK1/2 activation. Chaetocin alleviates NE budding-induced chromatin loss and ameliorates HGPS defects in cells and mice and significantly extends lifespan of HGPS mice. Collectively, we propose that progerin-induced NE budding participates in the induction of progeria, highlight the roles of chaetocin and sustained ERK1/2 activation in anti-aging, and provide a distinct avenue for treating HGPS.


Assuntos
Lamina Tipo A , Membrana Nuclear , Proteínas Nucleares , Progéria , Progéria/metabolismo , Progéria/tratamento farmacológico , Progéria/patologia , Progéria/genética , Animais , Lamina Tipo A/metabolismo , Lamina Tipo A/genética , Camundongos , Humanos , Membrana Nuclear/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Envelhecimento/metabolismo , Envelhecimento/efeitos dos fármacos , Cromatina/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Modelos Animais de Doenças , Autofagia/efeitos dos fármacos
2.
J Virol ; : e0143524, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39360826

RESUMO

The respiratory syncytial virus (RSV) matrix (M) protein plays an important role in infection as it can interact with viral components as well as the host cell actin microfilaments. The M-actin interaction may play a role in facilitating the transportation of virion components to the apical surface, where RSV is released. We show that M protein's association with actin is facilitated by palladin, an actin-binding protein. Cells were infected with RSV or transfected to express full-length M as a green fluorescent protein (GFP)-tagged protein, followed by removal of nuclear and cytosolic proteins to enrich for cytoskeleton and its associated proteins. M protein was present in inclusion bodies tethered to microfilaments in infected cells. In transfected cells, GFP-M was presented close to microfilaments, without association, suggesting the possible involvement of an additional protein in this interaction. As palladin can bind to proteins that also bind actin, we investigated its interaction with M. Cells were co-transfected to express GFP-M and palladin as an mCherry fluorescent-tagged protein, followed by cytoskeleton enrichment. M and palladin were observed to colocalize towards microfilaments, suggesting that palladin is involved in the M-actin interaction. In co-immunoprecipitation studies, M was found to associate with two isoforms of palladin, of 140 and 37 kDa. Interestingly, siRNA downregulation of palladin resulted in reduced titer of released RSV, while cell associated RSV titer increased, suggesting a role for palladin in virus release. Together, our data show that the M-actin interaction mediated by palladin is important for RSV budding and release.IMPORTANCERespiratory syncytial virus is responsible for severe lower respiratory tract infections in young children under 5 years old, the elderly, and the immunosuppressed. The interaction of the respiratory syncytial virus matrix protein with the host actin cytoskeleton is important in infection but has not been investigated in depth. In this study, we show that the respiratory syncytial virus matrix protein associates with actin microfilaments and the actin-binding protein palladin, suggesting a role for palladin in respiratory syncytial virus release. This study provides new insight into the role of the actin cytoskeleton in respiratory syncytial virus infection, a key host-RSV interaction in assembly. Understanding the mechanism by which the RSV M protein and actin interact will ultimately provide a basis for the development of therapeutics targeted at RSV infections.

3.
J Physiol ; 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39367867

RESUMO

Communication within the nervous system relies on the calcium-triggered release of neurotransmitter molecules by exocytosis of synaptic vesicles (SVs) at defined active zone release sites. While decades of research have provided detailed insight into the molecular machinery for SV fusion, much less is known about the mechanisms that form functional SVs during the development of synapses and that control local SV reformation following exocytosis in the mature nervous system. Here we review the current state of knowledge in the field, focusing on the pathways implicated in the formation and axonal transport of SV precursor organelles and the mechanisms involved in the local reformation of SVs within nerve terminals in mature neurons. We discuss open questions and outline perspectives for future research.

4.
Proc Natl Acad Sci U S A ; 121(41): e2316450121, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39356672

RESUMO

Deciphering the dynamic mechanism of ferroptosis can provide insights into pathogenesis, which is valuable for disease diagnosis and treatment. However, due to the lack of suitable time-resolved mechanosensitive tools, researchers have been unable to determine the membrane tension and morphology of the plasma membrane and the nuclear envelope during ferroptosis. With this research, we propose a rational strategy to develop robust mechanosensitive fluorescence lifetime probes which can facilitate simultaneous fluorescence lifetime imaging of the plasma membrane and nuclear envelope. Fluorescence lifetime imaging microscopy using the unique mechanosensitive probes reveal a dynamic mechanism for ferroptosis: The membrane tension of both the plasma membrane and the nuclear envelope decreases during ferroptosis, and the nuclear envelope exhibits budding during the advanced stage of ferroptosis. Significantly, the membrane tension of the plasma membrane is always larger than that of the nuclear envelope, and the membrane tension of the nuclear envelope is slightly larger than that of the nuclear membrane bubble. Meanwhile, the membrane lesions are repaired in the low-tension regions through exocytosis.


Assuntos
Membrana Celular , Ferroptose , Corantes Fluorescentes , Microscopia de Fluorescência , Membrana Nuclear , Ferroptose/fisiologia , Humanos , Corantes Fluorescentes/química , Membrana Celular/metabolismo , Membrana Nuclear/metabolismo , Microscopia de Fluorescência/métodos , Exocitose/fisiologia , Células HeLa
5.
Clin Oral Investig ; 28(11): 580, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39379623

RESUMO

OBJECTIVES: This study aimed to determine whether elective neck dissection can help improve outcomes in early-stage tongue and floor squamous cell carcinoma (SCC) by statistically analysing the relationship between information obtained from biopsy specimens and the incidence and prognosis of cervical lymph node metastasis (CLM). MATERIALS AND METHODS: Biopsy specimens of 103 patients diagnosed with early cT1-T2 cancer of the tongue and floor of the mouth were included. RESULTS: Multivariate analysis showed that the three parameters significantly correlated with CLM, and univariate analyses showed that budding score (BS) ≥ 5 and pathological depth of invasion (pDOI) ≥ 5 mm were independent risk factors for CLM. There were significant differences in the 5-year cumulative disease-specific survival between the BS < 5 and BS ≥ 5 groups, the pDOI < 5 mm and pDOI ≥ 5 mm groups, and the positive and negative budding and depth of invasion (BD) score groups. CONCLUSION: In early-stage tongue and floor of the mouth cancers with maximum tumour diameter ≤ 20 mm, it may be necessary to treat occult CLM during initial surgery based on the following preoperative criteria: pDOI ≥ 5 mm or BS ≥ 5 in biopsy specimens and DOI ≥ 8 mm on imaging. The BD model exhibited the highest specificity and proved helpful for CLM prediction. CLINICAL RELEVANCE: pDOI ≥ 5 mm and BS ≥ 5 were independent predictors of CLM and prognosis in early-stage tongue and floor of the mouth cancers with a maximum tumour diameter of 20 mm.


Assuntos
Carcinoma de Células Escamosas , Metástase Linfática , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasias da Língua , Humanos , Masculino , Feminino , Metástase Linfática/patologia , Pessoa de Meia-Idade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/secundário , Neoplasias da Língua/patologia , Neoplasias da Língua/cirurgia , Idoso , Adulto , Prognóstico , Esvaziamento Cervical , Soalho Bucal/patologia , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia , Fatores de Risco , Biópsia , Idoso de 80 Anos ou mais , Estudos Retrospectivos
6.
J Lipid Res ; : 100663, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39369791

RESUMO

Plasma membrane (PM) domains and order phases have been shown to play a key role in the assembly, release, and entry of several lipid-enveloped viruses. In the present study, we provide a mechanistic understanding of the Ebola virus (EBOV) matrix protein VP40 interaction with PM lipids and their effect on VP40 oligomerization, a crucial step for viral assembly and budding. VP40 matrix formation is sufficient to induce changes in the PM fluidity. We demonstrate that the distance between the lipid headgroups, the fatty acid tail saturation and the PM order are important factors for the stability of VP40 binding and oligomerization at the PM. Use of FDA-approved drugs to fluidize the PM, destabilizes the viral matrix assembly leading to a reduction in budding efficiency. Overall, these findings support an EBOV assembly mechanism that reaches beyond lipid headgroup specificity by using ordered PM lipid regions independent of cholesterol.

7.
Curr Med Sci ; 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39390217

RESUMO

OBJECTIVE: After endoscopic resection of colorectal cancer with submucosal invasion (pT1 CRC), additional surgical treatment is recommended if deep submucosal invasion (DSI) is present. This study aimed to further elucidate the risk factors for lymph node metastasis (LNM) in patients with pT1 CRC, especially the effect of DSI on LNM. METHODS: Patients with pT1 CRC who underwent lymph node dissection were selected. The Chi-square test and multivariate logistic regression were used to analyze the relationship between clinicopathological characteristics and LNM. The submucosal invasion depth (SID) was measured via 4 methods and analyzed with 3 cut-off values. RESULTS: Twenty-eight of the 239 patients presented with LNM (11.7%), and the independent risk factors for LNM included high histological grade (P=0.003), lymphovascular invasion (LVI) (P=0.004), intermediate to high budding (Bd 2/3) (P=0.008), and cancer gland rupture (CGR) (P=0.008). Moreover, the SID, width of submucosal invasion (WSI), and area of submucosal invasion (ASI) were not significantly different. When one, two, three or more risk factors were identified, the LNM rates were 1.1% (1/95), 12.5% (7/56), and 48.8% (20/41), respectively. CONCLUSION: Indicators such as the SID, WSI, and ASI are not risk factors for LNM and are subjective in their measurement, which renders them relatively inconvenient to apply in clinical practice. In contrast, histological grade, LVI, tumor budding and CGR are relatively straightforward to identify and have been demonstrated to be statistically significant. It would be prudent to focus on these histological factors rather than subjective measurements.

8.
Front Microbiol ; 15: 1467397, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39328910

RESUMO

The fission yeast Schizosaccharomyces pombe produces the hydroxamate-type siderophore ferrichrome (Fc). The biosynthesis of Fc requires the Fc synthase Sib1, the ornithine-N5-oxygenase Sib2, and the N5-hydroxyornithine-N5-transacetylase Sib3. In this study, we demonstrate the critical importance of the His248 residue of Sib3 in Fc production. Cells expressing a sib3H248A mutant allele fail to grow in iron-poor media without Fc supplementation. These sib3H248A mutant cells are consistently unable to promote Fc-dependent growth of Saccharomyces cerevisiae cells in cross-feeding experiments. Green fluorescent protein (GFP)-tagged wild-type Sib3 and mutant Sib3H248A exhibit a pancellular distribution. Coimmunoprecipitation assays revealed that both wild-type and Sib3H248A physically interact with Sib2. Further analysis identified a minimal C-terminal region from amino acids 290-334 of Sib3 that is required for interaction with Sib2. Deletion mapping analysis identified two regions of Sib2 as being required for its association with Sib3. The first region encompasses amino acids 1-135, and the second region corresponds to amino acids 281-358 of Sib2. Taken together, these results describe the first example of a physical interaction between an ornithine-N5-oxygenase and an N5-hydroxyornithine-N5-transacetylase controlling the biosynthesis of a hydroxamate-type siderophore.

9.
Ecotoxicol Environ Saf ; 285: 117112, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39332202

RESUMO

OBJECTIVE: Our research aims to investigate the specific mechanisms by which copper inhibits the asexual proliferation of Aurelia coerulea polyps. METHODS: Aurelia coerulea polyps were exposed to various CuSO4 concentrations to study metamorphosis and budding proliferation. Oxidative stress markers (ROS, MDA, CAT, H2O2, T-AOC, SOD) were measured in polyps and early strobilae. Transcriptomic analysis were used to compare differences in gene expression and enrichment pathways between untreated and copper-exposed polyps. Additionally, RT-qPCR was used to analyze the expression of key molecules. Antioxidant L-Ascorbic acid was applied to determine the role of oxidative stress in asexual reproduction of Aurelia coerulea polyps when exposed to copper. RESULTS: Copper inhibited strobilization and budding of Aurelia coerulea polyps in a dose-dependent manner, in which oxidative stress was involved. Transcriptomic data suggested that the DNA replication pathway was significantly enriched in early strobilae compared to polyps. However, copper treatment repealed the difference of DNA replication pathway between early strobilae compared and polyps. Transcriptomic data suggested that alanine, aspartate, and glutamate metabolism pathways were enriched in untreated budding polyps compared to copper-exposed polyps. After applying the antioxidant L-Ascorbic acid to copper-exposed polyps, various oxidative indicators changed to different extents, with increases in ROS, MDA, CAT, H2O2, and SOD and a decrease in T-AOC. Further more, the time required for polyps to develop into early strobila was shortened, indicating that the delay in metamorphosis caused by copper exposure was effectively alleviated. And the budding rate increased, indicating that the inhibition of budding proliferation caused by copper exposure was effectively alleviated. The expression of key genes were consist with the transcriptomic sequencing results. CONCLUSION: Copper exposure causes oxidative stress resulting in the inhibition of asexual reproduction in Aurelia coerulea polyps, including metamorphosis and budding.

10.
Cancers (Basel) ; 16(18)2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39335115

RESUMO

Both esophageal squamous cell carcinoma (ESQCC) and adenocarcinoma (EAC) are known to have poor prognosis. We aimed to investigate the invasion front areas of 57 ESQCC and 43 EAC cases to find histological signs of metastatic progression. Tumor cell clusters with different cell counts, including tumor buds (TBs) and poorly differentiated clusters (PDCs), were assessed. The presence of the recently described Stroma AReactive Invasion Front Area (SARIFA) phenomenon, which defines a direct contact between tumor cells and adipocytes, was more frequently observed in EAC than in ESQCC (p = 0.004). In adenocarcinomas, a higher prevalence of SARIFA was observed in tumors with a higher number of small clusters (TBs and small PDCs; p < 0.001); furthermore, both the high number of TBs (p = 0.016) and the presence of SARIFA (p = 0.001) correlated with a higher pT stage. SARIFA positivity in EAC (p = 0.011) and high TB in ESQCC (p = 0.0006) were found to be independent prognostic factors for lymph node metastases. Moreover, in ESQCC, the higher absolute number of both TBs and PDCs was associated with shorter overall survival (p = 0.0269 and p = 0.0377, respectively). Our results suggest that the histological subtypes of esophageal cancer behave differently, namely, that different features of the invasion front are of prognostic significance.

11.
J Fungi (Basel) ; 10(9)2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39330421

RESUMO

Eukaryotic cells must accurately transfer their genetic material and cellular components to their daughter cells. Initially, cells duplicate their chromosomes and subsequently segregate them toward the poles. The actomyosin ring, a crucial molecular machinery normally located in the middle of the cells and underneath the plasma membrane, then physically divides the cytoplasm and all components into two daughter cells, each ready to start a new cell cycle. This process, known as cytokinesis, is conserved throughout evolution. Defects in cytokinesis can lead to the generation of genetically unstable tetraploid cells, potentially initiating uncontrolled proliferation and cancer. This review focuses on the molecular mechanisms by which budding yeast cells build the actomyosin ring and the preceding steps involved in forming a scaffolding structure that supports the challenging structural changes throughout cytokinesis. Additionally, we describe how cells coordinate actomyosin ring contraction, plasma membrane ingression, and extracellular matrix deposition to successfully complete cytokinesis. Furthermore, the review discusses the regulatory roles of Cyclin-Dependent Kinase (Cdk1) and the Mitotic Exit Network (MEN) in ensuring the precise timing and execution of cytokinesis. Understanding these processes in yeast provides insights into the fundamental aspects of cell division and its implications for human health.

12.
Front Cell Dev Biol ; 12: 1464337, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39291266

RESUMO

After the endocytic and biosynthetic pathway converge, they partially share the route to the lysosome/vacuole. Similarly, the endocytic recycling and secretory pathways also partially share the route to the plasma membrane. The interaction of these transport pathways is mediated by endosomes and the trans-Golgi network (TGN), which act as sorting stations in endocytic and biosynthesis pathway, and endosomes has a bidirectional transport to and from the TGN. In mammalian cells endosomes can be largely classified as early/sorting, late, and recycling endosomes, based on their morphological features and localization of Rab family proteins, which are key factors in vesicular trafficking. However, these endosomes do not necessarily represent specific compartments that are comparable among different species. For instance, Rab5 localizes to early endosomes in mammalian cells but is widely localized to early-to-late endosomes in yeast, and to pre-vacuolar endosomes and the TGN in plant cells. The SNARE complexes are also key factors widely conserved among species and localized specifically to the endosomal membrane, but the localization of respective homologs is not necessarily consistent among species. These facts suggest that endosomes should be classified more inclusively across species. Here we reconsider the mammalian endosome system based on findings in budding yeast and other species and discuss the differences and similarities between them.

13.
Genome Biol Evol ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39293000

RESUMO

The genus Asparagus arose approximately 9-15 million years ago (Ma) and transitions from hermaphroditism to dioecy (separate sexes) occurred ∼3-4 Ma. Roughly 27% of extant Asparagus species are dioecious, while the remaining are bisexual with monoclinous flowers. As such, Asparagus is an ideal model taxon for studying early stages of dioecy and sex chromosome evolution in plants. Until now, however, understanding of diversification and shifts from hermaphroditism to dioecy in Asparagus has been hampered by the lack of robust species tree estimates for the genus. In this study, a genus-wide phylogenomic analysis including 1726 nuclear loci and comprehensive species sampling supports two independent origins of dioecy in Asparagus-first in a widely distributed Eurasian clade, then again in a clade restricted to the Mediterranean Basin. Modeling of ancestral biogeography indicates that both dioecy origins were associated with range expansion out of southern Africa. Our findings also revealed several bursts of diversification across the phylogeny, including an initial radiation in southern Africa that gave rise to 12 major clades in the genus, and more recent radiations that have resulted in paraphyly and polyphyly among closely related species, as expected given active speciation processes. Lastly, we report that the geographic origin of domesticated garden asparagus (Asparagus officinalis L.) was likely in western Asia near the Mediterranean Sea. The presented phylogenomic framework for Asparagus is foundational for ongoing genomic investigations of diversification and functional trait evolution in the genus and contributes to its utility for understanding the origin and early evolution of dioecy and sex chromosomes.

14.
J Gastrointest Oncol ; 15(4): 1545-1555, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39279933

RESUMO

Background: Tumor budding (TB) has been shown to be a poor prognostic indicator after colorectal cancer (CRC) surgery. The aim of the present study is to evaluate the predictive role of morphological features (e.g., the number, structure, and location of tumor buds, and their reaction with the extracellular mesenchyme) in postoperative adjuvant chemotherapy in surgically resectable stage II CRC. Methods: Between 2016 and 2019, 336 patients with stage II CRC who underwent radical surgery were enrolled in this study. TB status was determined according to the criteria adopted at the 2016 International Tumor Budding Consensus Conference (ITBCC). We retrospectively recorded all the clinical and pathological data and assessed the effect of different types of TB status on patients' recurrence-free survival (RFS) and overall survival (OS). Results: Of the 336 patients, 173, 88, and 75 were budding grade 1 (BD1), BD2, and BD3, respectively. The 5-year RFS rates were 84.6%, 81.2%, and 68.0% (P=0.01), and the 5-year OS rates were 91.0%, 83.3%, and 76.2% (P=0.007) in BD1, BD2, and BD3, respectively. TB grade was strongly associated with vascular invasion status and mucinous adenocarcinoma, and BD3 was detected in 51.7% of patients with positive vascular invasion. The multivariate analysis showed that only age, perineural invasion, and TB grade [BD2 vs. BD1, hazard ratio (HR) =1.468, 95% confidence interval (CI): 0.703-3.063, P=0.30; BD3 vs. BD1, HR =2.310, 95% CI: 1.154-4.625, P=0.01] had an independent effect on RFS. In addition, the Kaplan-Meier curve analysis showed that BD3 patients had the worst RFS (P=0.01). The OS of the adjuvant chemotherapy group was significantly improved compared to that of the surgery-only group in the BD1/2 patients (HR =0.278, 95% CI: 0.114-0.676, P=0.005) but not in the BD3 patients with significant interaction (Pinteraction=0.03). Conclusions: Our results indicate that TB could play a subsidiary role in selecting stage II CRC patients who could achieve a favorable prognosis with chemotherapy.

15.
Ann Diagn Pathol ; 73: 152375, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39312865

RESUMO

Growth pattern (GP), tumor budding (TB), poorly differentiated clusters (PDC), desmoplastic reaction pattern (DRP) and tumor-stroma ratio (TSR) are prognostic histomorphological parameters in colorectal cancer (CRC). Correlations between these parameters, their individual prognostic values, and their relationship with KRAS/NRAS/BRAF mutations have not been comprehensively examined. We aimed to investigate these associations, which have not been previously explored in this combination. 126 CRC cases were included. GP, TB, PDC, DRP and TSR were evaluated by two experienced pathologists. KRAS/NRAS/BRAF mutation profile were determined using qPCR. Demographic, clinicopathological and survival data were recorded. Interrelations were investigated by statistical analysis. Infiltrative GP was more frequent in high-score TB, PDC-G3, and stroma-high tumors (p < 0.05). High-score TB was more common in PDC-G3 and stroma-high tumors (p < 0.05). Immature DRP was more frequent in stroma-high tumors (p = 0.014). Among histomorphological parameters, a significant relationship was found only between infiltrative GP and the presence of KRAS mutation (p = 0.023). Moreover, GP was significantly associated with pT, lymphatic invasion, perineural invasion (p < 0.05). Effects on survival were assessed using Kaplan-Meier method and Cox proportional hazards model. TB and PDC were identified as independent predictors of overall survival. Higher TB score (p = 0.008) and higher PDC grade (p = 0.013) lead to worse survival. Interestingly, GP, DRP, TSR or KRAS/NRAS/BRAF mutations were not associated with overall survival. Our results highlight the prognostic significance of TB and PDC. We suggest incorporating TB and PDC into routine CRC reports. The association of KRAS mutation with infiltrative GP supports its role in the acquisition of invasive behavior.

16.
EMBO J ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39271795

RESUMO

To maintain protein homeostasis in changing nutrient environments, cells must precisely control the amount of their proteins, despite the accompanying changes in cell growth and biosynthetic capacity. As nutrients are major regulators of cell cycle length and progression, a particular challenge arises for the nutrient-dependent regulation of 'cell cycle genes', which are periodically expressed during the cell cycle. One important example are histones, which are needed at a constant histone-to-DNA stoichiometry. Here we show that budding yeast achieves histone homeostasis in different nutrients through a decoupling of transcript and protein abundance. We find that cells downregulate histone transcripts in poor nutrients to avoid toxic histone overexpression, but produce constant amounts of histone proteins through nutrient-specific regulation of translation efficiency. Our findings suggest that this allows cells to balance the need for rapid histone production under fast growth conditions with the tight regulation required to avoid toxic overexpression in poor nutrients.

17.
Eur J Surg Oncol ; 50(12): 108668, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39265415

RESUMO

BACKGROUND AND OBJECTIVE: Tumor budding is associated with the prognosis of several solid cancers, but further evidence is needed to identify its relation with esophageal cancer. Our study aims to assess the relationship between tumor budding and overall survival, disease-free survival, and clinicopathologic variables in EC. METHODS: Multiple electronic databases were searched and 20 relevant studies containing 3370 patients were identified. The fixed effects and a random-effects model were used to perform a meta-analysis. RESULT: Tumor budding was associated with poor overall survival in EC in both univariate analyses (HR:2.63; 95 % CI 2.06-3.38; p < 0.001) and multivariate analysis (HR: 2.00; 95 % CI 1.68 to 2.39; P < 0.001). Tumor budding was also associated with poor overall survival in subtypes of EC in subgroup analyses i.e. ESCC (HR:3.26; 95 % CI 2.48 to 4.29; P < 0.001), and EAC (HR:2.00; 95 % CI 1.36 to 2.95; P < 0.001) in univariate analysis and ESCC (HR: 2.95; 95 % CI 2.18 to 3.99; P < 0.001) and EAC (HR: 1.65; 95 % CI 1.33 to 2.04; P < 0.001) in multivariate analyses. In addition, tumor budding was also associated with poor DFS (HR: 3.39; 95 % CI 2.1 to 5.48; P < 0.001). Furthermore, tumor budding was associated with poor clinicopathologic factors like advanced T-stage, lymph node metastasis, lymphatic invasion, and venous invasion. CONCLUSION: The findings of our study suggest that tumor budding is a promising independent prognostic factor and is correlated with poor clinicopathologic variables of esophageal carcinoma. The inclusion of tumor budding in future grading systems may help in improving currently available staging systems of esophageal carcinoma.

18.
Cancer ; 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39239786

RESUMO

BACKGROUND: Currently, tumor budding (TB) is defined as an important factor for a poor prognosis in various types of cancers. The authors identified a significant presence of TB-like structures at the tumor invasive front in giant cell tumor of bone (GCTB), which may have the same biologic function as TB. The objective of this report was to describe the distribution of TB in GCTB and investigate its correlation with clinicopathologic characteristics, the immune microenvironment, survival prognosis, and response to denosumab treatment. METHODS: This multicenter cohort study included 426 patients with GCTB who received treatment between 2012 and 2021 at four centers. Two independent pathologists performed visual assessments of TBL structures in hematoxylin-and-eosin-stained tumor sections. Immunohistochemistry was used to evaluate tumor-infiltrating lymphocyte subtypes (CD3-positive, CD4-positive, CD8-positive, CD20-positive, programmed cell death protein-1-positive, programmed cell death-ligand 1positive, and FoxP3-positive) as well as Ki-67 expression levels in 426 tissue samples. These parameters were then analyzed for associations with patient outcomes (local recurrence-free survival [LRFS] and overall survival [OS]), clinicopathologic characteristics, and response to denosumab treatment. RESULTS: High-grade TB was associated with poorer LRFS and OS in both patient groups. In addition, TB was correlated with various clinicopathologic features, tumor-infiltrating lymphocyte expression, and response to denosumab treatment. TB outperformed the traditional Enneking and Campanacci staging systems in predicting patient LRFS and OS. CONCLUSIONS: The current data support the assessment of TBL structures as a reliable prognostic tool in GCTB, potentially aiding in the development of personalized treatment strategies for patients.

19.
Comput Methods Programs Biomed ; 257: 108352, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39241330

RESUMO

As the global incidence of cancer continues to rise rapidly, the need for swift and precise diagnoses has become increasingly pressing. Pathologists commonly rely on H&E-panCK stain pairs for various aspects of cancer diagnosis, including the detection of occult tumor cells and the evaluation of tumor budding. Nevertheless, conventional chemical staining methods suffer from notable drawbacks, such as time-intensive processes and irreversible staining outcomes. The virtual stain technique, leveraging generative adversarial network (GAN), has emerged as a promising alternative to chemical stains. This approach aims to transform biopsy scans (often H&E) into other stain types. Despite achieving notable progress in recent years, current state-of-the-art virtual staining models confront challenges that hinder their efficacy, particularly in achieving accurate staining outcomes under specific conditions. These limitations have impeded the practical integration of virtual staining into diagnostic practices. To address the goal of producing virtual panCK stains capable of replacing chemical panCK, we propose an innovative multi-model framework. Our approach involves employing a combination of Mask-RCNN (for cell segmentation) and GAN models to extract cytokeratin distribution from chemical H&E images. Additionally, we introduce a tailored dynamic GAN model to convert H&E images into virtual panCK stains, integrating the derived cytokeratin distribution. Our framework is motivated by the fact that the unique pattern of the panCK is derived from cytokeratin distribution. As a proof of concept, we employ our virtual panCK stains to evaluate tumor budding in 45 H&E whole-slide images taken from breast cancer-invaded lymph nodes . Through thorough validation by both pathologists and the QuPath software, our virtual panCK stains demonstrate a remarkable level of accuracy. In stark contrast, the accuracy of state-of-the-art single cycleGAN virtual panCK stains is negligible. To our best knowledge, this is the first instance of a multi-model virtual panCK framework and the utilization of virtual panCK for tumor budding assessment. Our framework excels in generating dependable virtual panCK stains with significantly improved efficiency, thereby considerably reducing turnaround times in diagnosis. Furthermore, its outcomes are easily comprehensible even to pathologists who may not be well-versed in computer technology. We firmly believe that our framework has the potential to advance the field of virtual stain, thereby making significant strides towards improved cancer diagnosis.

20.
Asian Pac J Cancer Prev ; 25(9): 3143-3149, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39342593

RESUMO

OBJECTIVE: The aim of this study was to analyze the expression of Snail in the colorectal adenocarcinoma. METHODS: This study used a cross-sectional design. Seventy four paraffin embedded block of Colorectal Adenocarcinoma were assessed using Snail rabbit polyclonal antibody and their expression were performed using Olympus CX-43 light microscope. The relationship between Snail expression with histopathological grading, tumor budding grading, lymphovascular invasion and metastases of colorectal adenocarcinoma ability were statistically analyzed by Mann Whitney tests and presented in tables using SPSS 27. RESULT: From 74 samples examined, in samples with low grade tumor budding (n=11), there were 9 samples (81.8%) with weak expression, while those with strong expression were 2 samples (18.2%). In samples with intermediate grade tumor budding (n=28), there were 17 samples (60.7%) with weak expression, while those with strong expression were 11 samples (39.3%). In samples with high grade tumor budding (n=35), there were 13 samples (37.1%) with weak expression, while those with strong expression were 22 samples (62.9%). In samples with lymphovascular invasion (n=14), there were 10 samples (71.4%) with strong expression, while those with weak expression were 4 samples (28.6%). In samples with metastases (n=23), there were 16 samples (69.6%) with strong expression, while those with weak expression were 7 samples (30.4%). There was a significant relationship between the expression of Snail with tumor budding grade (p=0.003), lymphovascular invasion and metastases (p=<0.001), but there was no significant relationship with histopathological grade (p=0.942). CONCLUSION: The Snail expression can be used as a prognostic factor in colorectal adenocarcinoma.


Assuntos
Adenocarcinoma , Biomarcadores Tumorais , Neoplasias Colorretais , Fatores de Transcrição da Família Snail , Humanos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/metabolismo , Prognóstico , Masculino , Feminino , Biomarcadores Tumorais/metabolismo , Pessoa de Meia-Idade , Estudos Transversais , Idoso , Seguimentos , Invasividade Neoplásica , Metástase Linfática , Adulto , Gradação de Tumores , Idoso de 80 Anos ou mais
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