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1.
PLoS Pathog ; 19(10): e1011721, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37812645

RESUMEN

V-ATPase, which comprises 13-14 subunits, is essential for pH homeostasis in all eukaryotes, but its proper function requires a regulator to assemble its subunits. While RAVE (regulator of H+-ATPase of vacuolar and endosomal membranes) and Raboconnectin-3 complexes assemble V-ATPase subunits in Saccharomyces cerevisiae and humans, respectively, the function of the RAVE complex in fungal pathogens remains largely unknown. In this study, we identified two RAVE complex components, Rav1 and Wdr1, in the fungal meningitis pathogen Cryptococcus neoformans, and analyzed their roles. Rav1 and Wdr1 are orthologous to yeast RAVE and human Rabconnectin-3 counterparts, respectively, forming the hybrid RAVE (hRAVE) complex. Deletion of RAV1 caused severe defects in growth, cell cycle control, morphogenesis, sexual development, stress responses, and virulence factor production, while the deletion of WDR1 resulted in similar but modest changes, suggesting that Rav1 and Wdr1 play central and accessary roles, respectively. Proteomics analysis confirmed that Wdr1 was one of the Rav1-interacting proteins. Although the hRAVE complex generally has V-ATPase-dependent functions, it also has some V-ATPase-independent roles, suggesting a unique role beyond conventional intracellular pH regulation in C. neoformans. The hRAVE complex played a critical role in the pathogenicity of C. neoformans, and RAV1 deletion attenuated virulence and impaired blood-brain barrier crossing ability. This study provides comprehensive insights into the pathobiological roles of the fungal RAVE complex and suggests a novel therapeutic strategy for controlling cryptococcosis.


Asunto(s)
Criptococosis , Cryptococcus neoformans , Proteínas de Saccharomyces cerevisiae , ATPasas de Translocación de Protón Vacuolares , Humanos , Proteínas de Saccharomyces cerevisiae/metabolismo , Cryptococcus neoformans/genética , Cryptococcus neoformans/metabolismo , ATPasas de Translocación de Protón Vacuolares/genética , Saccharomyces cerevisiae/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
2.
Curr Issues Mol Biol ; 44(11): 5139-5152, 2022 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-36354662

RESUMEN

Tumor budding (TB) is a small cluster of malignant cells at the invasive front of a tumor. Despite being an adverse prognosis marker, little research has been conducted on the tumor immune microenvironment of tumor buddings, especially in cervical cancer. Therefore, RNA sequencing was performed using 21 formalin-fixed, paraffin-embedded slides of cervical tissues, and differentially expressed genes (DEGs) were analyzed. Immune Pathway and Gene Database (IMPAGT) was generated for immune profiling. "Pathway in Cancer" was identified as the most enriched pathway for both up- and downregulated DEGs. Kyoto Encyclopedia of Genes and Genomes Mapper and Gene Ontology further revealed the activation of the PI3K/Akt signaling pathway. An IMPAGT analysis revealed immune dysregulation even at the tumor budding stage, especially in the PI3K/Akt/mTOR axis, with a high efficiency and integrity. These findings emphasized the clinical significance of tumor buddings and the necessity of blocking the overactivation of the PI3K/Akt/mTOR pathway to improve targeted therapy in cervical cancer.

3.
Phys Chem Chem Phys ; 24(19): 11782-11790, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35506867

RESUMEN

The ground and excited electronic states of the titled species are investigated with multi-reference configuration interaction and diffuse basis sets. We found that in addition to the valence orbitals, the inclusion of the 4s, 4p, and especially 3d orbitals (although with minimal population) of silicon in the active space of the reference complete active space self-consistent field wavefunction are necessary for the proper convergence of the calculations. We also demonstrate that the aug-cc-pVTZ basis set provides quite accurate results compared to both larger basis sets and basis set limit results at a lower computational cost. The excited states involve excitations within the 3s and 3p orbitals of silicon (especially for the mono- and di-hydrides), followed by excitations from the Si-H bonding orbitals to either silicon valence or Rydberg (4s, 4p) orbitals. The number of electronic states per energy unit decrease as we add hydrogen atoms, and the first excited state of SiH4 is at 9.0 eV and leads to SiH3 + H. All species have stable ground state structures with all hydrogen atoms bound to silicon, except for SiH4+ and SiH4-. The former dissociates to SiH2+ + H2, while the latter loses an electron or can dissociate forming H2 as well.

4.
J Phys Chem A ; 126(17): 2677-2689, 2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-35452242

RESUMEN

The rate coefficients for 52 hydrogen shift reactions for silicon nitrides containing up to 6 atoms of silicon and nitrogen have been calculated using the G3//B3LYP composite method and statistical thermodynamics. The overall reaction of substituted acyclic and cyclic silylenes to their respective silene and imine species by a 1,2-hydrogen shift reaction was sorted by three different types of H shift reactions using overall reaction thermodynamics: (1) endothermic H shift between N and Si:, (2) endothermic H shift between Si and Si:, and (3) exothermic H shift between Si and Si:. Endothermic H shift reactions between Si atoms have one dominant activation barrier where the exothermic H shift reaction between Si atoms has two barriers and a stable intermediate. The rate-determining step was determined to be from the intermediate to the substituted silene, and then kinetic parameters for the overall reaction were calculated for the two-step pathway. The single event pre-exponential factors, Ã, and activation energies, Ea, for the three different classes of hydrogen shift reactions of silicon nitrides were computed. The hydrogen shift reaction was explored for acyclic and cyclic monofunctional silicon nitrides, and the type of hydrogen shift reaction gives the most significant influence on the kinetic parameters. Using a supervised machine learning approach, the models for predicting the energy barrier of three different hydrogen shift reactions were generalized and suggested based on selected descriptors.

5.
Chemphyschem ; 21(22): 2627-2642, 2020 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-32853448

RESUMEN

With its high strength, high thermal stability, low density, and high electrical resistance, silicon-nitride-based ceramics have been widely used as gate insulating layers, oxidation masks, and passivation layers. Employing SiN nanomaterials in anode applications also improves rate performances and cycling stability of the lithium-ion batteries. However, a fundamental understanding of the SiN synthetic process remains elusive. SiN gas-phase synthesis can be tailored with a comprehensive understanding of the underlying thermodynamics. In comparison to the characterization data available for solid-state SiN materials, high-level theoretical studies on gas-phase materials possessing Si-N bonds and comprehensive investigation of the SiN chemistry, particularly for nanoclusters, are very uncommon. Thus, we performed a theoretical study of Si and SiN alloy acyclic hydrides and polycyclic clusters to predict electronic structures and thermochemistry using quantum chemical calculation and statistical thermodynamics. Electronic properties by way of highest and lowest occupied molecular orbital energy gap and natural bonding orbitals analysis were calculated to explore the influence of elemental composition and geometry on the stability. Our studies provide characteristic data of SiN species for a data-driven approach to map the design space for discovery of novel silicon-nitride-based ceramic materials for advanced electronic and coating applications.

6.
J Phys Chem A ; 122(51): 9851-9868, 2018 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-30484641

RESUMEN

There are limited studies available that predict the properties of hydrogenated silicon-germanium (SiGe) clusters. For this purpose, we conducted a computational study of 46 hydrogenated SiGe clusters (Si xGe yH z, 1 < X + Y ≤ 6) to predict the structural, thermochemical, and electronic properties. The optimized geometries of the Si xGe yH z clusters were investigated using quantum chemical calculations and statistical thermodynamics. The clusters contained 6 to 9 fused Si-Si, Ge-Ge, or Si-Ge bonds, i.e., bonds participating in more than one 3- to 4-membered rings, and different degrees of hydrogenation, i.e., the ratio of hydrogen to Si/Ge atoms varied depending on cluster size and degree of multifunctionality. Our studies have established trends in standard enthalpy of formation, standard entropy, and constant pressure heat capacity as a function of cluster composition and structure. A novel bond additivity correction model for SiGe chemistry was regressed from experimental data on seven acyclic Si/Ge/SiGe species to improve the accuracy of the standard enthalpy of formation predictions. Electronic properties were investigated by analysis of the HOMO-LUMO energy gap to study the effect of elemental composition on the electronic stability of Si xGe yH z clusters. These properties will be discussed in the context of tailored nanomaterials design and generalized using a machine learning approach.

7.
mSphere ; 9(1): e0055723, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38085018

RESUMEN

The N6-threonylcarbamoyl adenosine (t6A) tRNA modification is critical for ensuring translation fidelity across three domains of life. Our prior work highlighted the KEOPS complex, organized in a Pcc1-Kae1-Bud32-Cgi121 linear arrangement, not only serves an evolutionarily conserved role in t6A tRNA modification but also exerts diverse functional impacts on pathobiological characteristics in Cryptococcus neoformans, a leading cause of fungal meningitis worldwide. However, the extent to which the pleiotropic functions of the KEOPS complex are specifically tied to tRNA modification remains uncertain. To address this, we undertook a functional characterization of Sua5, responsible for generating the precursor threonylcarbamoyl-adenylate (TC-AMP) for t6A tRNA modification, using a reverse genetics approach. Comparative phenotypic analyses with KEOPS mutants revealed that Sua5 plays a vital role in multiple cellular processes, such as t6A tRNA modification, growth, sexual development, stress response, and virulence factor production, thus reflecting the multifaceted functions of the KEOPS complex. In support of this, sua5Δ bud32Δ double mutants showed phenotypes comparable to those of the corresponding single mutants. Intriguingly, a SUA5 allele lacking a mitochondria targeting sequence (SUA5MTSΔ) was sufficient to restore the wild-type phenotypes in the sua5Δ mutant, suggesting that Sua5's primary functional locus may be cytosolic, akin to the KEOPS complex. Further supporting this, the deletion of Qri7, a mitochondrial paralog of Kae1, had no discernible phenotypic impact on C. neoformans. We concluded that cytosolic t6A tRNA modifications, orchestrated by Sua5 and the KEOPS complex, are central to the regulation of diverse pathobiological functions in C. neoformans.IMPORTANCEUnderstanding cellular functions at the molecular level is crucial for advancing disease treatments. Our research reveals a critical connection between the KEOPS complex and Sua5 in Cryptococcus neoformans, a significant cause of fungal meningitis. While the KEOPS complex is known for its versatile roles in cellular processes, Sua5 is specialized in t6A tRNA modification. Our key finding is that the diverse roles of the KEOPS complex, ranging from cell growth and stress response to virulence, are fundamentally linked to its function in t6A tRNA modification. This conclusion is supported by the remarkable similarities between the impacts of Sua5 and KEOPS on these processes, despite their roles in different steps of the t6A modification pathway. This newfound understanding deepens our insight into fungal biology and opens new avenues for developing potential therapies against dangerous fungal diseases.


Asunto(s)
Cryptococcus neoformans , Meningitis Fúngica , Cryptococcus neoformans/genética , Cryptococcus neoformans/metabolismo , Adenosina/metabolismo , ARN de Transferencia/genética , ARN de Transferencia/metabolismo
8.
Front Cell Infect Microbiol ; 14: 1369301, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38774630

RESUMEN

Dual-specificity LAMMER kinases are highly evolutionarily conserved in eukaryotes and play pivotal roles in diverse physiological processes, such as growth, differentiation, and stress responses. Although the functions of LAMMER kinase in fungal pathogens in pathogenicity and stress responses have been characterized, its role in Cryptococcus neoformans, a human fungal pathogen and a model yeast of basidiomycetes, remains elusive. In this study, we identified a LKH1 homologous gene and constructed a strain with a deleted LKH1 and a complemented strain. Similar to other fungi, the lkh1Δ mutant showed intrinsic growth defects. We observed that C. neoformans Lkh1 was involved in diverse stress responses, including oxidative stress and cell wall stress. Particularly, Lkh1 regulates DNA damage responses in Rad53-dependent and -independent manners. Furthermore, the absence of LKH1 reduced basidiospore formation. Our observations indicate that Lkh1 becomes hyperphosphorylated upon treatment with rapamycin, a TOR protein inhibitor. Notably, LKH1 deletion led to defects in melanin synthesis and capsule formation. Furthermore, we found that the deletion of LKH1 led to the avirulence of C. neoformans in a systemic cryptococcosis murine model. Taken together, Lkh1 is required for the stress response, sexual differentiation, and virulence of C. neoformans.


Asunto(s)
Criptococosis , Cryptococcus neoformans , Proteínas Fúngicas , Virulencia , Animales , Femenino , Humanos , Ratones , Pared Celular/metabolismo , Criptococosis/microbiología , Cryptococcus neoformans/patogenicidad , Cryptococcus neoformans/genética , Cryptococcus neoformans/enzimología , Modelos Animales de Enfermedad , Daño del ADN , Cápsulas Fúngicas/metabolismo , Cápsulas Fúngicas/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Eliminación de Gen , Regulación Fúngica de la Expresión Génica , Melaninas/metabolismo , Ratones Endogámicos BALB C , Estrés Oxidativo , Fosforilación , Sirolimus/farmacología , Esporas Fúngicas/crecimiento & desarrollo , Estrés Fisiológico
9.
Life (Basel) ; 14(4)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38672714

RESUMEN

Tumor-associated macrophages (TAMs) play a pivotal role in the tumor microenvironment, influencing cancer progression and contributing to poor prognosis. However, in cervical cancer (CC), their significance and involvement are relatively less studied than in other gynecological cancers such as ovarian and endometrial cancer. This review aims to provide an overview of TAMs, covering their origins and phenotypes and their impact on CC progression, along with major TAM-targeted therapeutic approaches. Furthermore, we advocate for the integration of cutting-edge research methodologies, such as single-cell RNA sequencing and spatial RNA sequencing, to enable in-depth and comprehensive investigations into TAMs in CC, which would be beneficial in leading to more personalized and effective immunotherapy strategies for patients with CC.

10.
mBio ; 15(2): e0327523, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38193728

RESUMEN

The casein kinase 2 (CK2) complex has garnered extensive attention over the past decades as a potential therapeutic target for diverse human diseases, including cancer, diabetes, and obesity, due to its pivotal roles in eukaryotic growth, differentiation, and metabolic homeostasis. While CK2 is also considered a promising antifungal target, its role in fungal pathogens remains unexplored. In this study, we investigated the functions and regulatory mechanisms of the CK2 complex in Cryptococcus neoformans, a major cause of fungal meningitis. The cryptococcal CK2 complex consists of a single catalytic subunit, Cka1, and two regulatory subunits, Ckb1 and Ckb2. Our findings show that Cka1 plays a primary role as a protein kinase, while Ckb1 and Ckb2 have major and minor regulatory functions, respectively, in growth, cell cycle control, morphogenesis, stress response, antifungal drug resistance, and virulence factor production. Interestingly, triple mutants lacking all three subunits (cka1Δ ckb1Δ ckb2Δ) exhibited more severe phenotypic defects than the cka1Δ mutant alone, suggesting that Ckb1/2 may have Cka1-independent functions. In a murine model of systemic cryptococcosis, cka1Δ and cka1Δ ckb1Δ ckb2Δ mutants showed severely reduced virulence. Transcriptomic, proteomic, and phosphoproteomic analyses further revealed that the CK2 complex controls a wide array of effector proteins involved in transcriptional regulation, cell cycle control, nutrient metabolisms, and stress responses. Most notably, CK2 disruption led to dysregulation of key signaling cascades central to C. neoformans pathogenicity, including the Hog1, Mpk1 MAPKs, cAMP/PKA, and calcium/calcineurin signaling pathways. In summary, our study provides novel insights into the multifaceted roles of the fungal CK2 complex and presents a compelling case for targeting it in the development of new antifungal drugs.IMPORTANCEThe casein kinase 2 (CK2) complex, crucial for eukaryotic growth, differentiation, and metabolic regulation, presents a promising therapeutic target for various human diseases, including cancer, diabetes, and obesity. Its potential as an antifungal target is further highlighted in this study, which explores CK2's functions in C. neoformans, a key fungal meningitis pathogen. The CK2 complex in C. neoformans, comprising the Cka1 catalytic subunit and Ckb1/2 regulatory subunits, is integral to processes like growth, cell cycle, morphogenesis, stress response, drug resistance, and virulence. Our findings of CK2's role in regulating critical signaling pathways, including Hog1, Mpk1 MAPKs, cAMP/PKA, and calcium/calcineurin, underscore its importance in C. neoformans pathogenicity. This study provides valuable insights into the fungal CK2 complex, reinforcing its potential as a target for novel antifungal drug development and pointing out a promising direction for creating new antifungal agents.


Asunto(s)
Criptococosis , Cryptococcus neoformans , Diabetes Mellitus , Meningitis Fúngica , Neoplasias , Animales , Ratones , Humanos , Quinasa de la Caseína II/genética , Quinasa de la Caseína II/metabolismo , Cryptococcus neoformans/metabolismo , Antifúngicos/metabolismo , Calcio/metabolismo , Calcineurina/metabolismo , Proteómica , Transducción de Señal , Criptococosis/microbiología , Obesidad
11.
Genes Genomics ; 46(8): 881-898, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38847972

RESUMEN

BACKGROUND: Since most of the commonly known oral diseases are explained in link with balance of microbial community, an accurate bacterial taxonomy profiling for determining bacterial compositional network is essential. However, compared to intestinal microbiome, research data pool related to oral microbiome is small, and general 16S rRNA screening method has a taxonomy misclassification issue in confirming complex bacterial composition at the species level. OBJECTIVE: Present study aimed to explore bacterial compositional networks at the species level within saliva of 39 oral disease patients (Dental Caries group: n = 26 and Periodontitis group: n = 13) through comparison with public Korean-specific healthy oral microbiome data. METHODS: Here, we applied comprehensive molecular diagnostics based on qRT-PCR and Sanger sequencing methods to complement the technical limitations of NGS-based 16S V3-V4 amplicon sequencing technology. RESULTS: As a result of microbiome profiling at the genus level, relative frequencies of many nitrate-reducing bacteria within each oral disease group were found to be significantly low compared to the healthy group. In addition, the molecular diagnostics-based bacterial identification method allowed the determination of the correct taxonomy of screened primary colonizers (Streptococcus and Actinomyces unclassification clusters) for each oral disease. Finally, as with the results of microbiome profiling at the genus level, many core-species classified within the saliva of each oral disease group were also related to nitrate-reduction, and it was estimated that various pathogens associated with each disease formed a bacterial network with the core-species. CONCLUSION: Our study introduced a novel approach that can compensate for the difficulty of identifying an accurate bacterial compositional network at the species level due to unclear taxonomy classification by using the convergent approach of NGS-molecular diagnostics. Ultimately, we suggest that our experimental approach and results could be potential reference materials for researchers who intend to prevent oral disease by determining the correlation between oral health and bacterial compositional network according to the changes in the relative frequency for nitrate-reducing species.


Asunto(s)
Microbiota , ARN Ribosómico 16S , Saliva , Humanos , Saliva/microbiología , ARN Ribosómico 16S/genética , Femenino , Masculino , Microbiota/genética , Adulto , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Persona de Mediana Edad , Caries Dental/microbiología , Caries Dental/diagnóstico , Periodontitis/microbiología , Periodontitis/diagnóstico , Bacterias/genética , Bacterias/clasificación , Bacterias/aislamiento & purificación
12.
Oncol Lett ; 28(6): 588, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39411203

RESUMEN

Cervical adenocarcinoma (AC), a subtype of uterine cervical cancer (CC), poses a challenge due to its resistance to therapy and poor prognosis compared with squamous cervical carcinoma. Streptococcus agalactiae [group B Streptococcus (GBS)], a Gram-positive coccus, has been associated with cervical intraepithelial neoplasia in CC. However, the underlying mechanism interaction between GBS and CC, particularly AC, remains elusive. Leveraging The Cancer Genome Atlas public data and time-series transcriptomic data, the present study investigated the interaction between GBS and AC, revealing activation of two pivotal pathways: 'MAPK signaling pathway' and 'mTORC1 signaling'. Western blotting, reverse transcription-quantitative PCR and cell viability assays were performed to validate the activation of these pathways and their role in promoting cancer cell proliferation. Subsequently, the present study evaluated the efficacy of two anticancer drugs targeting these pathways (binimetinib and ridaforolimus) in AC cell treatment. Binimetinib demonstrated a cytostatic effect, while ridaforolimus had a modest impact on HeLa cells after 48 h of treatment, as observed in both cell viability and cytotoxicity assays. The combination of binimetinib and ridaforolimus resulted in a significantly greater cytotoxic effect compared to binimetinib or ridaforolimus monotherapy, although the synergy score indicated an additive effect. In general, the MAPK and mTORC1 signaling pathways were identified as the main pathways associated with GBS and AC cells. The combination of binimetinib and ridaforolimus could be a potential AC treatment.

13.
Biosci Microbiota Food Health ; 43(1): 73-80, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38188664

RESUMEN

The reasons for sex-associated gut microbiota differences have not been determined, and although sex hormones, diet, and other factors are considered to contribute to them, many of these factors are age related. To shed light on this complex interplay, our study aimed to investigate and compare the gut microbial compositions of males and females across a broad range of ages, aiming to identify sex-associated disparities and potential causal factors. Our study encompassed a comprehensive analysis of gut microbiota data obtained from 444 Japanese individuals, ranging from newborns to centenarians, sourced from the DNA Data Bank of Japan. We categorized the subjects into 13 distinct age groups and examined their relative microbial abundances, as well as alpha and beta diversities, in relation to sex and age. No difference was observed between gut microbiota relative abundances or alpha diversities between men and women at any age. However, the study showed that the heterogeneity of gut microbiota among women in their 20s was greater than in men. To confirm the general occurrence of this difference, we conducted additional analyses using seven datasets: three from Japan and four from other countries. Interestingly, this variance was particularly noticeable within Japanese women. We also showed a potential link between the observed heterogeneity and dietary fiber intake. It is hoped this study will provide clues that aid in the identification of factors responsible for sex-associated differences in gut microbiota compositions.

14.
Microbiol Spectr ; 11(3): e0068523, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37036370

RESUMEN

Blocking of nutrient uptake and amino acid biosynthesis are considered potential targets for next-generation antifungal drugs against pathogenic fungi, including Cryptococcus neoformans. In this regard, the sulfate assimilation pathway is particularly attractive, as it is only present in eukaryotes such as plants and fungi, yet not in mammals. Here, we demonstrated that the adenylyl sulfate kinase (Met14) in the sulfate assimilation pathway is not essential yet is required for the viability of C. neoformans due to its involvement in biosynthesis of two sulfur-containing amino acids, cysteine and methionine. Met14-dependent cysteine and methionine biosynthesis was found to significantly contribute to a diverse range of pathobiological processes in C. neoformans. Met14-dependent cysteine rather than methionine biosynthesis was also found to play pivotal roles in cell growth and tolerance to environmental stresses and antifungal drugs. In contrast, the Met14-dependent methionine biosynthesis was found to be more important than cysteine biosynthesis for the production of major cryptococcal virulence factors of melanin pigments and polysaccharide capsules. Finally, we also found that despite its attenuated virulence in an insect model, Galleria mellonella, the met14Δ mutant yielded no difference in virulence in a murine model of systemic cryptococcosis. Hence, clinical inhibition of Met14-dependent amino acid biosynthetic pathways may not be advantageous for the treatment of systemic cryptococcosis. IMPORTANCE Current antifungal drugs have several limitations, such as drug resistance, severe side effects, and a narrow spectrum. Therefore, novel antifungal targets are urgently needed. To this end, fungal sulfur amino acid biosynthetic pathways are considered potential targets for development of new antifungal agents. Here, we demonstrated that Met14 in the sulfate assimilation pathway promotes growth, stress response, and virulence factor production in C. neoformans via synthesis of sulfur-containing amino acids methionine and cysteine. Met14-dependent cysteine rather than methionine synthesis was found to be critical for growth and stress responses, whereas Met14-dependent methionine synthesis was more important for the production of antiphagocytic capsules and antioxidant melanin in C. neoformans. Surprisingly, deletion of the MET14 gene was found to attenuate cryptococcal virulence in an insect model, yet not in a murine model. Collectively, our results showed that Met14-dependent cysteine and methionine biosynthesis play roles that are distinct from each other in C. neoformans. Moreover, Met14 is unlikely to be a suitable anticryptococcal drug target.


Asunto(s)
Criptococosis , Cryptococcus neoformans , Animales , Ratones , Cryptococcus neoformans/genética , Cisteína/metabolismo , Antifúngicos/farmacología , Antifúngicos/metabolismo , Modelos Animales de Enfermedad , Melaninas/metabolismo , Melaninas/farmacología , Cápsulas/metabolismo , Cápsulas/farmacología , Criptococosis/microbiología , Factores de Virulencia/metabolismo , Metionina/metabolismo , Metionina/farmacología , Azufre/metabolismo , Sulfatos/metabolismo , Sulfatos/farmacología , Mamíferos
15.
Life (Basel) ; 13(12)2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38137942

RESUMEN

Lymphovascular space invasion (LVSI) is the presence of tumor emboli in the endothelial-lined space at the tumor body's invasive edge. LVSI is one of three Sedlis criteria components-a prognostic tool for early cervical cancer (CC)-essential for indicating poor prognosis, such as lymph node metastasis, distant metastasis, or shorter survival rate. Despite its clinical significance, an in-depth comprehension of the molecular mechanisms or immune dynamics underlying LVSI in CC remains elusive. Therefore, this study investigated tumor-immune microenvironment (TIME) dynamics of the LVSI-positive group in CC. RNA sequencing included formalin-fixed paraffin-embedded (FFPE) slides from 21 CC patients, and differentially expressed genes (DEGs) were analyzed. Functional analysis and immune deconvolution revealed aberrantly enriched PI3K/Akt pathway activation and a heterogenic immune composition with a low abundance of regulatory T cells (Treg) between LVSI-positive and LVSI-absent groups. These findings improve the comprehension of LSVI TIME and immune mechanisms, benefiting targeted LVSI therapy for CC.

16.
Cancer Genomics Proteomics ; 20(1): 75-87, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36581343

RESUMEN

BACKGROUND/AIM: Cervical cancer is the fourth most common type of cancer in women worldwide and it is a major cause of cancer-related deaths in developing countries. Despite the marked reduction observed in the rates of the disease as a result of screening programs, it is necessary to develop robust biomarkers that can detect the neoplastic progression early in HPV-related cervical lesions. MATERIALS AND METHODS: We performed comparative mRNA sequencing from exfoliative cervical cytology samples from nine Korean women using the Illumina NovaSeq6000 platform. Each pathological tissue was matched to the corresponding cytological sample. The pathologic diagnosis was scrutinized with ancillary immunohistochemistry and was considered a confirmative (endpoint) diagnosis. The pathological diagnoses consisted of three cases of chronic cervicitis, 2 high-grade squamous intraepithelial lesions (HSILs), 2 squamous cell carcinomas in situ (CIS), and 2 invasive squamous cell carcinomas (SQCCs), respectively. Using bioinformatic analyses, differentially expressed genes (DEGs; fold change ≥1.5; p<0.05) were applied for Gene Ontology (GO), Gene Set Enrichment Analysis (GSEA), and protein-protein interaction (PPI) networks. RESULTS: From a total of 55,882 genes, 438 DEGs were pinpointed; 282 genes were up-regulated and 156 genes down-regulated. These transcriptomic profiles were clearly divided into neoplastic (HSIL, CIS, and SQCC; ≥HSILs) and non-neoplastic lesions. The up-regulated DEGs were HIF-1a, EDN1, PIK3R3, PPP1CA and AKR1C1. GO, GSEA, and PPI network analyses showed marked associations with metabolism, proteolysis, or proteoglycan process pathways in cervical carcinogenesis. CONCLUSION: The transcriptomic analysis using exfoliative cervical cells was more likely representative of its corresponding histopathological diagnosis, thus emphasizing its potential utility in clinical practice. This study provides comprehensive transcriptomic network analyses for robust biomarkers that might present a high potential risk of progression to cancer in the exfoliative cervical cytology; our findings support their clinical utility for improved cervical cancer screening.


Asunto(s)
Carcinoma de Células Escamosas , Infecciones por Papillomavirus , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patología , Displasia del Cuello del Útero/diagnóstico , Displasia del Cuello del Útero/metabolismo , Displasia del Cuello del Útero/patología , Proyectos Piloto , Transcriptoma , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/diagnóstico , Detección Precoz del Cáncer , Carcinoma de Células Escamosas/genética , Papillomaviridae/genética , Fosfatidilinositol 3-Quinasas/metabolismo
17.
Indian J Med Microbiol ; 46: 100426, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37945119

RESUMEN

PURPOSE: Group B Streptococcus (GBS) colonization and vaginal microbiome (VMB) dysbiosis are associated with adverse perinatal outcomes. However, the role of GBS colonization in maternal VMB remains unclear. Herein, we aimed to investigate this relationship and identify additional pathogens associated with GBS colonization for potential implications in understanding their clinical significance. MATERIALS AND METHODS: Vaginal swab samples were obtained before delivery from nine women with normal pregnancies for GBS detection and 16S rRNA gene sequencing. The diversity analysis and community state types clustering were used to compare the GBS-positive vs. GBS-negative groups. ANCOM-BC was implemented to identify differentially abundant microbes (DAMs) associated with GBS colonization. The correlation and receiver operating characteristic analysis were used to evaluate the relationship between DMAs and clinical parameters. RESULTS: There were 6/9 (66,7%) GBS-negative pregnant women. The α-diversity index (p â€‹= â€‹0.71 for observed operational taxonomic units and p â€‹= â€‹0.90 for Shannon diversity), ß-diversity index (p â€‹= â€‹0.583), and community state types clustering (p â€‹= â€‹0.23) were not significantly different between the GBS-positive and -negative groups. Four DAMs, namely, Actinomyces, Shigella, Fenollaria, and Gemella, were significantly associated with GBS colonization, reflecting the dynamicity of the gestational VMB. Their abundances were negatively correlated with birth weight and had acceptable discriminating ability in premature membrane rupture (area under the curve, 0.9). CONCLUSIONS: Despite the absence of significant effects on overall VMB composition, our preliminary results investigated that maternal GBS colonization related to high abundance of four pathogens with potential clinical utility as microbial signatures.


Asunto(s)
Microbiota , Complicaciones Infecciosas del Embarazo , Infecciones Estreptocócicas , Embarazo , Femenino , Humanos , Proyectos Piloto , ARN Ribosómico 16S/genética , Streptococcus agalactiae/genética
18.
Microorganisms ; 11(6)2023 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-37374919

RESUMEN

Uterine cervical cancer (CC) is a complex, multistep disease primarily linked to persistent infection with high-risk human papillomavirus (HR-HPV). However, it is widely acknowledged that HR-HPV infection alone cannot account for the formation and progression of CC. Emerging evidence suggests that the cervicovaginal microbiome (CVM) also plays a significant role in HPV-related CC. Certain bacteria, such as Fusobacterium spp., Porphyromonas, Prevotella, and Campylobacter, are currently being considered as potential microbiomarkers for HPV-positive CC. However, the composition of the CVM in CC is inconsistent; thus, further studies are needed. This review comprehensively discusses the complex interplay between HPV and the CVM in cervical carcinogenesis. It is postulated that the dynamic interaction between HPV and the CVM creates an imbalanced cervicovaginal microenvironment that triggers dysbiosis, enhances HPV persistence, and promotes cervical carcinogenesis. Moreover, this review aims to provide updated evidence on the potential role of bacteriotherapy, particularly probiotics, in the treatment of CC.

19.
Microorganisms ; 10(12)2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36557651

RESUMEN

Group B Streptococcus (GBS, Streptococcus agalactiae) is a Gram-positive bacterium that is commonly found in the gastrointestinal and urogenital tracts. However, its colonization during pregnancy is an important cause of maternal and neonatal morbidity and mortality worldwide. Herein, we specifically looked at GBS in relation to the field of Obstetrics (OB) along with the field of Gynecology (GY). In this review, based on the clinical significance of GBS in the field of OBGY, topics of how GBS is being detected, treated, and should be prevented are addressed.

20.
Diagnostics (Basel) ; 12(7)2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35885476

RESUMEN

A rapid method for obtaining group B streptococcus (GBS) screening results has been required in the obstetric field. We aimed to determine the diagnostic performance of the Loop-Mediated Isothermal Amplification (LAMP) assay is acceptable compared to the existing polymerase chain reaction (PCR) assay. The study involved 527 pregnant women aged 19 to 44 years. Rectovaginal swabs were collected between 35 and 37 weeks of gestation or prior to impending preterm births or term labor without GBS screening. We presented the diagnostic performance of the LAMP assay with a 95% confidence interval (CI) compared to the PCR and microbiological culture. In total, 115 (21.8%), 115 (21.8%) and 23 (4.4%) patients showed positive results using the LAMP, PCR assay and microbiological culture method, respectively. The LAMP assay showed 100% sensitivity (95% CI, 96.8-100.0), 100% specificity (95% CI, 99.1-100.0) and 100% diagnostic accuracy (95% CI, 99.3-100.0) with the reference being the PCR assay. Meanwhile, the LAMP assay showed 87.0% sensitivity (95% CI, 71.0-100.0), 81.2% specificity (95% CI, 77.6-84.7), and 81.4% diagnostic accuracy (95% CI, 78.0-84.8) with the microbiological culture as a reference. This study presented the LAMP assay as an acceptable method for GBS screening with a similar performance to the existing PCR method.

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