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1.
Appl Opt ; 62(33): 8905-8910, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-38038036

RESUMEN

We propose a polarization insensitive, flexible ultra-broadband terahertz (THz) metamaterial absorber. It consists of a chromium composite resonator on the top, a polyimide (PI) dielectric layer in the middle, and a chromium substrate. The simulation results show that the absorption achieves more than 90% ultra-wideband absorption in the range of 1.92-4.34 THz. The broadband absorption is produced by the combination of electric dipole resonance and magnetic resonance, as well as impedance matching with free space. Due to the rotational symmetry of the unit structure, the absorber is insensitive to polarization of the THz wave and has a larger range of incident angles. The total thickness of the absorber is only 13.4 µm, showing highly flexible and excellent high-temperature resistance characteristics. Therefore, it has potential applications in THz wave stealth and electromagnetic shielding.

2.
Appl Opt ; 62(4): 1103-1108, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36821170

RESUMEN

Actively controlling the phase of a terahertz (THz) wave is of great significance for beaming, tunable focusing, and holography. We present a THz phase modulator based on an electrically triggered vanadium dioxide (V O 2) reconfigurable metasurface. The unit cell of the device consists of two split-ring resonators embedded with a V O 2 ribbon. By electrically triggering the insulator-to-metal transition of V O 2, the resonance mode and resonance intensity of the unit cell can be dynamically controlled. The simulation results show that the structure can achieve a phase shift of about 360° in the range of 1.03-1.13 THz, and the reflection amplitude can reach 80%. The device has potential applications in THz imaging, radar, broadband wireless communications, and array phase control.

3.
Biosci Biotechnol Biochem ; 87(1): 63-73, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36367541

RESUMEN

Antimicrobial peptides (AMPs) show broad-spectrum microbicidal activity against bacteria, fungi, and viruses, and have been considered as one of the most promising candidates to overcome bacterial antimicrobial resistance. Structural modification of AMPs is an effective strategy to develop high-efficiency and low-toxicity antibacterial agents. A series of peptides GHaR6R, GHaR7R, GHaR8R, and GHaR9W with arginine replacement of histidine (His) derived from temporin-GHa of Hylarana guentheri were designed and synthesized. These derived peptides exhibit antibacterial activity against Staphylococcus aureus, and GHaR8R exerts bactericidal effect within 15 min at 4 × MIC (25 µm). The derived peptides caused rapid depolarization of bacteria, and the cell membrane damage was monitored using quartz crystal microbalance with dissipation assay, which suggests that they target cell membranes to exert antibacterial effects. The derived peptides can effectively eradicate mature biofilms of S. aureus. Taken together, the derived peptides are promising antibacterial agent candidates against S. aureus.


Asunto(s)
Antiinfecciosos , Infecciones Estafilocócicas , Humanos , Staphylococcus aureus , Histidina/farmacología , Arginina/farmacología , Pruebas de Sensibilidad Microbiana , Antiinfecciosos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Antibacterianos/farmacología , Antibacterianos/química , Biopelículas , Bacterias
4.
Med Sci Monit ; 28: e934282, 2022 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-35124688

RESUMEN

BACKGROUND This study compared the effects of peritoneal dialysis and hemodialysis on cognitive dysfunction and health-related quality of life (HRQOL) in end-stage renal disease (ESRD) patients and analyzed other potential influencing factors. MATERIAL AND METHODS A total of 265 patients who received dialysis at our hospital were included and divided into the hemodialysis group (n=115) and the peritoneal dialysis group (n=150). The cognitive performance was assessed by the Beijing version of the Montreal Cognitive Assessment. The Kidney Disease Quality of 36-Item Short Form Survey and a kidney disease-related quality of life assessment were used for evaluating HRQOL. Univariate and multivariate linear regression analyses were used to explore the effects of dialysis on cognitive dysfunction and HRQOL. RESULTS As compared with the hemodialysis group, the peritoneal dialysis group had lower scores on the Montreal Cognitive Assessment (ß=-8.35, 95% CI: -9.85 to -6.86), 36-Item Short Form Survey (ß=-10.20, 95% CI: -11.94 to -8.45), and kidney disease-related quality of life assessment (ß=-8.67, 95% CI: -10.10 to -7.23). After adjustment for sex, age, BMI, marital status, educational level, income level, presence of diabetes, duration of kidney disease, duration of dialysis, and dialysis frequency, the results were consistent with that of the crude model. CONCLUSIONS In the present study, patients receiving peritoneal dialysis had worse cognitive dysfunction and worse HRQOL compared to patients receiving hemodialysis, which might lead to poorer outcomes of ESRD patients. The related factors affecting cognitive dysfunction and HRQOL were also explored, which could help clinicians to determine the optimal treatment for ESRD patients.


Asunto(s)
Disfunción Cognitiva/epidemiología , Encuestas Epidemiológicas/métodos , Fallo Renal Crónico/epidemiología , Fallo Renal Crónico/terapia , Diálisis Peritoneal/métodos , Calidad de Vida/psicología , Diálisis Renal/métodos , Beijing/epidemiología , Disfunción Cognitiva/psicología , Estudios Transversales , Femenino , Humanos , Fallo Renal Crónico/psicología , Masculino , Persona de Mediana Edad , Diálisis Peritoneal/psicología , Diálisis Renal/psicología
5.
Plant Cell Environ ; 41(7): 1539-1550, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29532482

RESUMEN

One of the ways in which plants can respond to temperature is via alternative splicing (AS). Previous work showed that temperature changes affected the splicing of several circadian clock gene transcripts. Here, we investigated the role of RNA-binding splicing factors (SFs) in temperature-sensitive AS of the clock gene LATE ELONGATED HYPOCOTYL (LHY). We characterized, in wild type plants, temperature-associated isoform switching and expression patterns for SF transcripts from a high-resolution temperature and time series RNA-seq experiment. In addition, we employed quantitative RT-PCR of SF mutant plants to explore the role of the SFs in cooling-associated AS of LHY. We show that the splicing and expression of several SFs responds sufficiently, rapidly, and sensitively to temperature changes to contribute to the splicing of the 5'UTR of LHY. Moreover, the choice of splice site in LHY was altered in some SF mutants. The splicing of the 5'UTR region of LHY has characteristics of a molecular thermostat, where the ratio of transcript isoforms is sensitive to temperature changes as modest as 2 °C and is scalable over a wide dynamic range of temperature. Our work provides novel insight into SF-mediated coupling of the perception of temperature to post-transcriptional regulation of the clock.


Asunto(s)
Empalme Alternativo , Arabidopsis/genética , Proteínas de Unión al ADN/genética , Factores de Transcripción/genética , Empalme Alternativo/genética , Empalme Alternativo/fisiología , Arabidopsis/fisiología , Ritmo Circadiano/genética , Proteínas de Unión al ADN/fisiología , Regulación de la Expresión Génica de las Plantas , Isoformas de ARN/genética , Isoformas de ARN/fisiología , Reacción en Cadena en Tiempo Real de la Polimerasa , Temperatura , Factores de Transcripción/fisiología
6.
Opt Lett ; 43(1): 17-20, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-29328226

RESUMEN

We experimentally demonstrated a tunable terahertz bandpass filter based on microelectromechanical systems (MEMS) reconfigurable metamaterials. The unit cell of the filter consists of two split-ring resonators (SRRs) and a movable bar. Initially, the movable bar situates at the center of the unit cell, and the filter has two passbands whose central frequencies locate at 0.65 and 0.96 THz. The intensity of the two passbands can be actively modulated by the movable bar, and a maximum modulation depth of 96% is achieved at 0.96 THz. The mechanism of tunability is investigated using the finite-integration time-domain method. The result shows that the image currents induced on the movable bar are opposite the resonance currents induced on the SRRs and, thus, weaken the oscillating intensity of the resonance currents. This scheme paves the way to dynamically control and switch the terahertz wave at some constant frequencies utilizing induced image currents.

7.
Proc Natl Acad Sci U S A ; 112(43): 13178-83, 2015 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-26460029

RESUMEN

Glacial-interglacial changes in the distribution of C3/C4 vegetation on the Chinese Loess Plateau have been related to East Asian summer monsoon intensity and position, and could provide insights into future changes caused by global warming. Here, we present δ(13)C records of bulk organic matter since the Last Glacial Maximum (LGM) from 21 loess sections across the Loess Plateau. The δ(13)C values (range: -25‰ to -16‰) increased gradually both from the LGM to the mid-Holocene in each section and from northwest to southeast in each time interval. During the LGM, C4 biomass increased from <5% in the northwest to 10-20% in the southeast, while during the mid-Holocene C4 vegetation increased throughout the Plateau, with estimated biomass increasing from 10% to 20% in the northwest to >40% in the southeast. The spatial pattern of C4 biomass in both the LGM and the mid-Holocene closely resembles that of modern warm-season precipitation, and thus can serve as a robust analog for the contemporary East Asian summer monsoon rain belt. Using the 10-20% isolines for C4 biomass in the cold LGM as a reference, we derived a minimum 300-km northwestward migration of the monsoon rain belt for the warm Holocene. Our results strongly support the prediction that Earth's thermal equator will move northward in a warmer world. The southward displacement of the monsoon rain belt and the drying trend observed during the last few decades in northern China will soon reverse as global warming continues.


Asunto(s)
Clima , Calentamiento Global , Migración Humana , Lluvia , Asia , Humanos
9.
Heliyon ; 10(6): e28172, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38560664

RESUMEN

The MTCH2 protein is located on the mitochondrial outer membrane and regulates mitochondria-related cell death. This study set out to investigate the role of MTCH2 in the underlying pathophysiological mechanisms of breast cancer (BC). MTCH2 expression levels in BC were analyzed using bioinformatics prior to verification by cell lines in vitro. Experiments of over-expression and siRNA-mediated knockdown of MTCH2 were conducted to assess its biological functions, including its effects on cellular proliferation and cycle progression. Xenografts were utilised for in vivo study and signaling pathway alterations were examined to identify the mechanisms driven by MTCH2 in BC proliferation and cell-cycle regulation. MTCH2 was up-regulated in BC and correlated with patients' overall survival. Over-expression of MTCH2 promoted cellular proliferation and cycle progression, while silencing MTCH2 had the opposite effect. Xenograft experiments were utilised to confirm the in vitro cellular findings and it was identified that the PI3K/Akt signaling pathway was activated by MTCH2 over-expression and suppressed by its silencing. Moreover, the activation of IGF-1R rescued cellular growth and cycle arrest induced by MTCH2-silencing. Overall, this study reveals that expression of MTCH2 in BC is upregulated and potentiates cellular proliferation and cycle progression via the PI3K/Akt pathway.

10.
Eur J Pharmacol ; 977: 176737, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38866362

RESUMEN

The prevalence of nonalcoholic fatty liver disease (NAFLD) has been increasing worldwide in recent years, causing severe economic and social burdens. Therefore, the lack of currently approved drugs for anti-NAFLD has gradually gained attention. SIRT1, as a member of the sirtuins family, is now the most widely studied in the pathophysiology of many metabolic diseases, and has great potential for preventing and treating NAFLD. Natural products such as Diosgenin (DG) have the potential to be developed as clinical drugs for the treatment of NAFLD due to their excellent multi-target therapeutic effects. In this study, we found that DG can activate the SIRT1/PGC-1α pathway and upregulate the expression of its downstream targets nuclear respiratory factor 1 (NRF1), complex IV (COX IV), mitofusin-2 (MFN2), and PPARα (perox-isome proliferator-activated receptor α) in SD rats induced by high-fat diet (HFD) and HepG2 cells caused by free fatty acids (FFAs, sodium oleate: sodium palmitate = 2:1). Conversely, the levels of dynamin-related protein 1 (DRP1) and inflammatory factors, including NF-κB p65, IL6, and TNFα, were downregulated both in vitro and in vivo. This improved mitochondrial dysfunction, fatty acid oxidation (FAO), lipid accumulation, steatosis, oxidative stress, and hepatocyte inflammation. Subsequently, we applied SIRT1 inhibitor EX527 and SIRT1 agonist SRT1720 to confirm further the necessity of activating SIRT1 for DG to exert therapeutic effects on NAFLD. In summary, these results further demonstrate the potential therapeutic role of DG as a SIRT1 natural agonist for NAFLD. (Graphical Abstracts).


Asunto(s)
Diosgenina , Hígado , Enfermedad del Hígado Graso no Alcohólico , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Transducción de Señal , Sirtuina 1 , Animales , Humanos , Masculino , Ratas , Dieta Alta en Grasa/efectos adversos , Diosgenina/farmacología , Diosgenina/uso terapéutico , Diosgenina/análogos & derivados , Células Hep G2 , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Estrés Oxidativo/efectos de los fármacos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Sirtuina 1/metabolismo
11.
Aging (Albany NY) ; 16(4): 3674-3693, 2024 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-38364254

RESUMEN

Head and neck squamous cell carcinoma (HNSCC) ranks as the eighth most prevalent malignancy globally and has the eighth greatest fatality rate when compared to all other forms of cancer. The inhibitor of apoptosis protein (IAP) family comprises a collection of apoptosis-negative modulators characterized by at least one single baculovirus IAP repeat (BIR) domain in its N-terminal region. While the involvement of the IAP family is associated with the initiation and progression of numerous tumours, its specific role in HNSCC remains poorly understood. Thus, this study aimed to comprehensively examine changes in gene expression, immunomodulatory effects, prognosis, and functional enrichment of HNSCC utilising bioinformatics analysis. Elevated levels of distinct IAP family members were observed to varying degrees in HNSCC, with high BIRC2 expression indicating a worse prognosis. Additionally, Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to probe the enrichment of gene expression and biological processes related to the IAP family in HNSCC. The infiltration levels of immune cells were shown to be strongly associated with the IAP gene expression, as determined by subsequent analysis. Hence, BIRC2 could be an effective immunotherapy target for HNSCC. Collectively, novel knowledge of the biological roles and prognostic implications of IAP family members in HNSCC is presented in this study.


Asunto(s)
Neoplasias de Cabeza y Cuello , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Pronóstico , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/terapia , Biomarcadores de Tumor/genética , Proteínas Inhibidoras de la Apoptosis/genética , Regulación Neoplásica de la Expresión Génica
12.
Int Immunopharmacol ; 138: 112581, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38944952

RESUMEN

Metabolic-associated fatty liver disease (MAFLD) is one of the most common liver diseases worldwide; however, its pathogenesis and treatment methods have not been perfected. NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) is a promising therapeutic target for MAFLD. Diosgenin (DG) is a natural compound that was identified in a traditional Chinese herbal medicine, which has pharmacological effects, such as anti-inflammatory, antioxidant, hepatoprotective, and hypolipidemic activities. In this study, we examined the effects and molecular mechanisms of DG on MAFLD in vitro and in vivo. We established a rat model by administering a high-fat diet (HFD). We also generated an in vitro MAFLD model by treating HepG2 cells with free fatty acids (FFAs). The results indicated that DG attenuated lipid accumulation and liver injury in both in vitro and in vivo models. DG downregulated the expression of NLRP3, apoptosis-associated speckle-like protein (ASC), cysteinyl aspartate specific proteinase-1 (caspase-1), gasdermin D (GSDMD), GSDMD-n, and interleukin-1ß (IL-1ß). In addition, we silenced and overexpressed NLRP3 in vitro to determine the effects of DG on antiMAFLD. Silencing NLRP3 enhanced the effect of DG on the treatment of MAFLD, whereas NLRP3 overexpression reversed its beneficial effects. Taken together, the results show that DG has a favorable effect on attenuating MAFLD through the hepatic NLRP3 inflammasome-dependent signaling pathway. DG represents a natural NLRP3 inhibitor for the MAFLD treatment.

13.
Clin Chim Acta ; 556: 117849, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38417779

RESUMEN

Colorectal cancer (CRC) is a type of gastrointestinal cancer with high morbidity and mortality rates, and is often accompanied by distant metastases. Metastasis is a major cause of shortened survival time and poor treatment outcomes for patients with CRC. However, the molecular mechanisms underlying the metastasis of CRC remain unclear. Exosomes are a class of small extracellular vesicles that originate from almost all human cells and can transmit biological information (e.g., nucleic acids, lipids, proteins, and metabolites) from secretory cells to target recipient cells. Recent studies have revealed that non-coding RNAs (ncRNAs) can be released by exosomes into the tumour microenvironment or specific tissues, and play a pivotal role in tumorigenesis by regulating a series of key molecules or signalling pathways, particularly those involved in tumour metastasis. Exosomal ncRNAs have potential as novel therapeutic targets for CRC metastasis, and can also be used as liquid biopsy biomarkers because of their specificity and sensitivity. Therefore, further investigations into the biological function and clinical value of exosomal ncRNAs will be of great value for the prevention, early diagnosis, and treatment of CRC metastasis.


Asunto(s)
Neoplasias Colorrectales , Exosomas , Vesículas Extracelulares , Humanos , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/diagnóstico , ARN no Traducido/genética , Exosomas/metabolismo , Vesículas Extracelulares/patología , Transducción de Señal , Microambiente Tumoral
14.
Transl Cancer Res ; 12(4): 859-872, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37180657

RESUMEN

Background: RTN4IP1 interacts with a membranous protein of endoplasmic reticulum (RTN4), this study was to explore the role RTN4IP1 involved in breast cancer (BC). Methods: After RNAseq data of The Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) project were downloaded, correlations between RTN4IP1 expression and clinicopathologic variables, as well as expression levels between cancerous samples and non-cancerous ones were tested. Differentially expressed genes (DEGs) and functional enrichment, gene set enrichment analysis (GSEA) and immune infiltration analysis were conduct for bioinformatics analysis. After logistic regression, Kaplan-Meier curve of disease-specific survival (DSS), univariate and multivariate COX analysis, a nomogram was established for prognosis. Results: RTN4IP1 expression was up-regulated in BC tissue, significantly associated with estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) status (P<0.001). The 771 DEGs linked RTN4IP1 to glutamine metabolism and mitoribosome-associated quality control. Functional enrichment pointed to DNA metabolic process, mitochondrial matrix and inner membrane, ATPase activity, cell cycle and cellular senescence; whereas GSEA indicated regulation of cellular cycle, G1_S DNA damage checkpoints, drug resistance and metastasis. Eosinophil cells, natural killer (NK) cells and Th 2 cells were found to be correlated with RTN4IP1 expression (R=-0.290, -0.277 and 0.266, respectively, P<0.001). RTN4IP1high BC had worse DSS than RTN4IP1low ones [hazard ratio (HR) =2.37, 95% confidential interval (CI): (1.48-3.78), P<0.001], which has independent prognostic value (P<0.05). Conclusions: Overexpressed in BC tissue, RTN4IP1 predicts adverse prognosis for patients with BC, especially in infiltrating ductal carcinoma, infiltrating lobular carcinoma, Stage II, Stages III&IV and luminal A subtype.

15.
Int J Gen Med ; 16: 2519-2530, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37346812

RESUMEN

Background: Hepatocellular carcinoma (HCC) is a major cause of cancer death in the world. The aim of this study was to establish a new model to predict the prognosis of HCC. Materials and Methods: The mRNA, miRNA and lncRNA expression profiles of early (stage I-II) and late (stage III-IV) stage HCC patients were acquired from The Cancer Genome Atlas (TCGA) database. The differentially expressed mRNAs (DEmRNAs), miRNAs (DEmiRNAs) and lncRNAs (DElncRNAs) were identified between early and late stage HCC. Key molecules associated with the prognosis, and important immune cell types in HCC were identified. The nomogram based on incorporating age, gender, stage, and all important factors was constructed to predict the survival of HCC. Results: A total of 1516 DEmRNAs, 97 DEmiRNAs and 87 DElncRNAs were identified. A DElncRNA-DEmiRNA-DEmRNA regulatory network including 78 mRNAs, 50 miRNAs and 1 lncRNA was established. Among the regulatory network, 11 molecules were significantly correlated with the prognosis of HCC based on Lasso regression analysis. Then, Preadipocytes and 3 survival-associated DEmRNAs were identified as crucial biomarkers. Subsequently, a nomogram with a differentiation degree of 0.758, including 1 immune cell, 11 mRNAs and 3 miRNAs, was generated. Conclusion: Our study constructed a model by incorporating clinical information, significant biomarkers and immune cells to predict the survival of HCC, which achieved a good performance.

16.
Cancer Med ; 12(24): 21861-21872, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38083903

RESUMEN

OBJECTIVE: To generate an image-driven biomarker (Rad_score) to predict tumor-infiltrating regulatory T lymphocytes (Treg) in breast cancer (BC). METHODS: Overall, 928 BC patients were enrolled from the Cancer Genome Atlas (TCGA) for survival analysis; MRI (n = 71 and n = 30 in the training and validation sets, respectively) from the Cancer Imaging Archive (TCIA) were retrieved and subjected to repeat least absolute shrinkage and selection operator for feature reduction. The radiomic scores (rad_score) for Treg infiltration estimation were calculated via support vector machine (SVM) and logistic regression (LR) algorithms, and validated on the remaining patients. RESULTS: Landmark analysis indicated Treg infiltration was a risk factor for BC patients in the first 5 years and after 10 years of diagnosis (p = 0.007 and 0.018, respectively). Altogether, 108 radiomic features were extracted from MRI images, 4 of which remained for model construction. Areas under curves (AUCs) of the SVM model were 0.744 (95% CI 0.622-0.867) and 0.733 (95% CI 0.535-0.931) for training and validation sets, respectively, while for the LR model, AUCs were 0.771 (95% CI 0.657-0.885) and 0.724 (95% CI 0.522-0.926). The calibration curves indicated good agreement between prediction and true value (p > 0.05), and DCA shows the high clinical utility of the radiomic model. Rad_score was significantly correlated with immune inhibitory genes like CTLA4 and PDCD1. CONCLUSIONS: High Treg infiltration is a risk factor for patients with BC. The Rad_score formulated on radiomic features is a novel tool to predict Treg abundance in the tumor microenvironment.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/diagnóstico por imagen , Linfocitos T Reguladores , Microambiente Tumoral , Radiómica , Algoritmos
17.
Front Pharmacol ; 14: 1255809, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37900156

RESUMEN

Colon adenocarcinoma (COAD) is among the most prevalent cancers worldwide, ranking as the third most prevalent malignancy in incidence and mortality. The somatostatin receptor (SSTR) family comprises G-protein-coupled receptors (GPCRs), which couple to inhibitory G proteins (Gi and Go) upon binding to somatostatin (SST) analogs. GPCRs are involved in hormone release, neurotransmission, cell growth inhibition, and cancer suppression. However, their roles in COAD remain unclear. This study used bioinformatics to investigate the expression, prognosis, gene alterations, functional enrichment, and immunoregulatory effects of the SSTR family members in COAD. SSTR1-4 are differentially downregulated in COAD, and low SSTR2 expression indicates poor survival. Biological processes and gene expression enrichment of the SSTR family in COAD were further analyzed using the Kyoto Encyclopedia of Genes and Genomes and Gene Ontology. A strong correlation was observed between SSTR expression and immune cell infiltration. We also quantified SSTR2 expression in 25 COAD samples and adjacent normal tissues using quantitative real-time polymerase chain reaction. We analyzed its correlation with the dendritic cell-integrin subunit alpha X marker gene. The biomarker exploration of the solid tumors portal was used to confirm the correlation between SSTR2 with immunomodulators and immunotherapy responses. Our results identify SSTR2 as a promising target for COAD immunotherapy. Our findings provide new insights into the biological functions of the SSTR family and their implications for the prognosis of COAD.

18.
J Cancer ; 14(15): 2848-2866, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37781078

RESUMEN

Hepatocellular carcinoma (HCC) is a malignant tumor with high morbidity and mortality rates. The inhibitors of apoptosis (IAP) family act as oncogenes in various tumor types; however, their functions in HCC remain unclear. Here, we used integrated bioinformatics analysis and experimental verification to assess the expression and the prognostic and clinical value of the IAP family in HCC. Using the University of Alabama at Birmingham Cancer Data Analysis Portal (UALCAN) and the Tumor Immune Estimation Resource (TIMER), we analyzed the expression profiles of IAP family members in HCC tissue, normal tissues, and in patients with different stages and grades of HCC. We further verified the expression level of BIRC2 in 25 HCC samples and matched adjacent normal tissues using quantitative real-time PCR (qRT-PCR), and analyzed its correlation with the marker gene of T-helper type 1 cells (Th1)-STAT1. Meanwhile, the association between BIRC2 and the immunotherapeutic response or immunomodulators was confirmed using the Biomarker Exploration of Solid Tumors (BEST) database. The results showed that NAIP, BIRC2, BIRC3, XIAP, BIRC5, and BIRC6 mRNAs were overexpressed in HCC. The clinical stages, pathological grades, and other clinicopathological features of HCC were closely related to the expression levels of the IAP family members, especially the BIRC2 and BIRC5, which were found to be potential prognostic biomarkers for HCC. Expression of the IAPs was strongly associated with immune cell infiltration. Based on the infiltrative status of various immune cells, HCC patients with high BIRC2 and BIRC5 expression demonstrated poor overall survival (OS) rates. In patients with HCC, BIRC2 expression was noticeably elevated. Concurrently, the expression levels of BIRC2 and STAT1 showed a favorable correlation. BEST database analysis revealed that BIRC2 was a negative predictor of responsiveness to anti-programmed cell death ligand 1 (PD-L1)/cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) inhibitor treatment in HCC, and BIRC2 mRNA expression levels were positively correlated with the expression levels of the immune checkpoint genes programmed cell death protein 1 (PD-1), PD-L1, and CTLA-4 in HCC. Consequently, the IAP family may play a role in carcinogenesis and cancer-immune system interactions in HCC. Our results demonstrate that IAP family members may be viable predictive biomarkers and therapeutic targets for HCC.

19.
Protein Pept Lett ; 30(2): 183-192, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36476441

RESUMEN

BACKGROUND: Temporin is one family of the shortest antimicrobial peptides found in Ranidae frogs. Staphylococcus aureus is one of the main pathogens of suppurative diseases and food contamination, causing severe local or systemic infections in humans. Temporin-GHa (GHa) was previously obtained from Hylarana guentheri, showing weak antibacterial activity against S. aureus. Most temporin peptides are positively charged by arginine and lysine; however, GHa contains histidine. OBJECTIVE: In order to investigate the impact of positively charged amino acid on its antibacterial and antibiofilm activity, GHa4R was designed and synthesized by replacing histidine with arginine in GHa. METHODS: The antibacterial activity and efficacy against S. aureus were detected by minimum inhibitory concentration, minimum bactericidal concentration, and time-killing kinetics assays. The action mechanism was determined by propidium iodide uptake and scanning electron microscopy assays. The antibiofilm activity was measured by the MTT method. Eradication of biofilm was observed by fluorescence microscope. RESULTS: Compared to GHa, GHa4R had stronger antibacterial activity and bactericidal efficacy against S. aureus. Impressively, GHa4R presented antibacterial activity against methicillin-resistant S. aureus (MRSA). It was barely affected by temperature, pH, and storage period, showing high stability. Furthermore, it increased the permeability of the cell membrane and damaged the membrane integrity, leading to cell death. In addition, GHa4R did not induce antibiotic resistance in S. aureus in 30 days, but the MIC of vancomycin was doubled. It not only inhibited S. aureus biofilm formation but also eradicated 24 h-biofilms. CONCLUSION: The above-mentioned characteristics make GHa4R a promising candidate for the treatment of S. aureus infections.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Staphylococcus aureus , Humanos , Histidina , Antibacterianos/farmacología , Antibacterianos/química , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Biopelículas , Pruebas de Sensibilidad Microbiana
20.
Nat Commun ; 14(1): 5590, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37696831

RESUMEN

Male breast cancer (MBC) is a rare but aggressive malignancy with cellular and immunological characteristics that remain unclear. Here, we perform transcriptomic analysis for 111,038 single cells from tumor tissues of six MBC and thirteen female breast cancer (FBC) patients. We find that that MBC has significantly lower infiltration of T cells relative to FBC. Metastasis-related programs are more active in cancer cells from MBC. The activated fatty acid metabolism involved with FASN is related to cancer cell metastasis and low immune infiltration of MBC. T cells in MBC show activation of p38 MAPK and lipid oxidation pathways, indicating a dysfunctional state. In contrast, T cells in FBC exhibit higher expression of cytotoxic markers and immune activation pathways mediated by immune-modulatory cytokines. Moreover, we identify the inhibitory interactions between cancer cells and T cells in MBC. Our study provides important information for understanding the tumor immunology and metabolism of MBC.


Asunto(s)
Neoplasias de la Mama Masculina , Humanos , Femenino , Masculino , Análisis de Expresión Génica de una Sola Célula , Terapia de Inmunosupresión , Metabolismo de los Lípidos/genética , Ácidos Grasos
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