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1.
Nature ; 579(7798): 284-290, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32103175

RESUMEN

Cancer recurrence after surgery remains an unresolved clinical problem1-3. Myeloid cells derived from bone marrow contribute to the formation of the premetastatic microenvironment, which is required for disseminating tumour cells to engraft distant sites4-6. There are currently no effective interventions that prevent the formation of the premetastatic microenvironment6,7. Here we show that, after surgical removal of primary lung, breast and oesophageal cancers, low-dose adjuvant epigenetic therapy disrupts the premetastatic microenvironment and inhibits both the formation and growth of lung metastases through its selective effect on myeloid-derived suppressor cells (MDSCs). In mouse models of pulmonary metastases, MDSCs are key factors in the formation of the premetastatic microenvironment after resection of primary tumours. Adjuvant epigenetic therapy that uses low-dose DNA methyltransferase and histone deacetylase inhibitors, 5-azacytidine and entinostat, disrupts the premetastatic niche by inhibiting the trafficking of MDSCs through the downregulation of CCR2 and CXCR2, and by promoting MDSC differentiation into a more-interstitial macrophage-like phenotype. A decreased accumulation of MDSCs in the premetastatic lung produces longer periods of disease-free survival and increased overall survival, compared with chemotherapy. Our data demonstrate that, even after removal of the primary tumour, MDSCs contribute to the development of premetastatic niches and settlement of residual tumour cells. A combination of low-dose adjuvant epigenetic modifiers that disrupts this premetastatic microenvironment and inhibits metastases may permit an adjuvant approach to cancer therapy.


Asunto(s)
Epigénesis Genética , Terapia Genética , Células Supresoras de Origen Mieloide/fisiología , Neoplasias/terapia , Microambiente Tumoral , Animales , Azacitidina/farmacología , Benzamidas/farmacología , Diferenciación Celular , Movimiento Celular/efectos de los fármacos , Quimioterapia Adyuvante , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Ratones , Células Supresoras de Origen Mieloide/citología , Metástasis de la Neoplasia/terapia , Neoplasias/cirugía , Piridinas/farmacología , Receptores CCR2/genética , Receptores de Interleucina-8B/genética , Microambiente Tumoral/efectos de los fármacos
2.
Blood ; 140(9): 1038-1051, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35767715

RESUMEN

Protein tyrosine phosphatase nonreceptor type 22 (PTPN22) is a protein tyrosine phosphatase that negatively regulates T-cell signaling. However, whether it is expressed and functions in platelets remains unknown. Here we investigated the expression and role of PTPN22 in platelet function. We reported PTPN22 expression in both human and mouse platelets. Using PTPN22-/- mice, we showed that PTPN22 deficiency significantly shortened tail-bleeding time and accelerated arterial thrombus formation without affecting venous thrombosis and the coagulation factors VIII and IX. Consistently, PTPN22-deficient platelets exhibited enhanced platelet aggregation, granule secretion, calcium mobilization, lamellipodia formation, spreading, and clot retraction. Quantitative phosphoproteomic analysis revealed the significant difference of phosphodiesterase 5A (PDE5A) phosphorylation in PTPN22-deficient platelets compared with wild-type platelets after collagen-related peptide stimulation, which was confirmed by increased PDE5A phosphorylation (Ser92) in collagen-related peptide-treated PTPN22-deficient platelets, concomitant with reduced level and vasodilator-stimulated phosphoprotein phosphorylation (Ser157/239). In addition, PTPN22 interacted with phosphorylated PDE5A (Ser92) and dephosphorylated it in activated platelets. Moreover, purified PTPN22 but not the mutant form (C227S) possesses intrinsic serine phosphatase activity. Furthermore, inhibition of PTPN22 enhanced human platelet aggregation, spreading, clot retraction, and increased PDE5A phosphorylation (Ser92). In conclusion, our study shows a novel role of PTPN22 in platelet function and arterial thrombosis, identifying new potential targets for future prevention of thrombotic or cardiovascular diseases.


Asunto(s)
Hemostasis , Proteína Tirosina Fosfatasa no Receptora Tipo 22 , Trombosis , Animales , Plaquetas/metabolismo , Humanos , Ratones , Ratones Noqueados , Activación Plaquetaria , Agregación Plaquetaria , Pruebas de Función Plaquetaria , Proteína Tirosina Fosfatasa no Receptora Tipo 22/metabolismo , Trombosis/genética
3.
J Fluoresc ; 34(1): 425-436, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37284963

RESUMEN

A novel reagent named 4-(N-methyl-1,3-dioxo-benzoisoquinolin-6-yl-oxy)benzene sulfonyl chloride (MBIOBS-Cl) for the determination of estrogens in food samples by high-performance liquid chromatography (HPLC) with fluorescence detection has been developed. Estrogens could be easily labeled by MBIOBS-Cl in Na2CO3-NaHCO3 buffer solution at pH 10.0. The complete labeling reaction for estrogens could be accomplished within five minutes, the corresponding derivatives exhibited strong fluorescence with the maximum excitation and emission wavelengths at 249 nm and 443 nm, respectively. The derivatization conditions, such as the molar ratio of reagent to estrogens, derivatization time, pH, temperature, and buffers were optimized. Derivatives were sufficiently stable to be efficiently analyzed by HPLC with a reversed-phase Agilent ZORBAX 300SB-C18 column with a good baseline resolution. Excellent linear correlations were obtained for all estrogen derivatives with correlation coefficients greater than 0.9998. Ultrasonic-Assisted extraction was used to optimize the extraction of estrogens from meat samples with a recovery higher than 82%. The detection limits (LOD, S/N = 3) of the method ranged from 0.95 to 3.3 µg· kg-1. The established method, which is fast, simple, inexpensive, and environment friendly, can be successfully applied for the detection of four steroidal estrogens from meat samples with little matrix interference.


Asunto(s)
Estrógenos , Carne , Estrógenos/análisis , Cromatografía Líquida de Alta Presión/métodos , Carne/análisis
4.
Proc Natl Acad Sci U S A ; 118(47)2021 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-34789566

RESUMEN

We report a molecular switching ensemble whose states may be regulated in synergistic fashion by both protonation and photoirradiation. This allows hierarchical control in both a kinetic and thermodynamic sense. These pseudorotaxane-based molecular devices exploit the so-called Texas-sized molecular box (cyclo[2]-(2,6-di(1H-imidazol-1-yl)pyridine)[2](1,4-dimethylenebenzene); 14+, studied as its tetrakis-PF6- salt) as the wheel component. Anions of azobenzene-4,4'-dicarboxylic acid (2H+•2) or 4,4'-stilbenedicarboxylic acid (2H+•3) serve as the threading rod elements. The various forms of 2 and 3 (neutral, monoprotonated, and diprotonated) interact differently with 14+, as do the photoinduced cis or trans forms of these classic photoactive guests. The net result is a multimodal molecular switch that can be regulated in synergistic fashion through protonation/deprotonation and photoirradiation. The degree of guest protonation is the dominating control factor, with light acting as a secondary regulatory stimulus. The present dual input strategy provides a complement to more traditional orthogonal stimulus-based approaches to molecular switching and allows for the creation of nonbinary stimulus-responsive functional materials.

5.
J Integr Plant Biol ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961693

RESUMEN

Dwarfing is a pivotal agronomic trait affecting both yield and quality. Citrus species exhibit substantial variation in plant height, among which internode length is a core element. However, the molecular mechanism governing internode elongation remains unclear. Here, we unveiled that the transcriptional cascade consisting of B-BOX DOMAIN PROTEIN 22 (BBX22) and ELONGATED HYPOCOTYL 5 (HY5) finely tunes plant height and internode elongation in citrus. Loss-of-function mutations of BBX22 in an early-flowering citrus (Citrus hindsii "SJG") promoted internode elongation and reduced pigment accumulation, whereas ectopic expression of BBX22 in SJG, sweet orange (C. sinensis), pomelo (C. maxima) or heterologous expression of BBX22 in tomato (Solanum lycopersicum) significantly decreased internode length. Furthermore, exogenous application of gibberellin A3 (GA3) rescued the shortened internode and dwarf phenotype caused by BBX22 overexpression. Additional experiments revealed that BBX22 played a dual role in regulation internode elongation and pigmentation in citrus. On the one hand, it directly bound to and activated the expression of HY5, GA metabolism gene (GA2 OXIDASE 8, GA2ox8), carotenoid biosynthesis gene (PHYTOENE SYNTHASE 1, PSY1) and anthocyanin regulatory gene (Ruby1, a MYB DOMAIN PROTEIN). On the other hand, it acted as a cofactor of HY5, enhancing the ability of HY5 to regulate target genes expression. Together, our results reveal the critical role of the transcriptional cascade consisting of BBX22 and HY5 in controlling internode elongation and pigment accumulation in citrus. Unraveling the crosstalk regulatory mechanism between internode elongation and fruit pigmentation provides key genes for breeding of novel types with both dwarf and health-beneficial fortification in citrus.

6.
Chin J Cancer Res ; 36(1): 90-102, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38455367

RESUMEN

Objective: There is an ongoing debate about whether the management of gastroenteropancreatic (GEP) neuroendocrine carcinoma (NEC) should follow the guidelines of small-cell lung cancer (SCLC). We aim to identify the genetic differences of GEPNEC and its counterpart. Methods: We recruited GEPNEC patients as the main cohort, with lung NEC and digestive adenocarcinomas as comparative cohorts. All patients undergone next-generation sequencing (NGS). Different gene alterations were compared and analyzed between GEPNEC and lung NEC (LNEC), GEPNEC and adenocarcinoma to yield the remarkable genes. Results: We recruited 257 patients, including 99 GEPNEC, 57 LNEC, and 101 digestive adenocarcinomas. Among the mutations, KRAS, RB1, TERT, IL7R, and CTNNB1 were found to have different gene alterations between GEPNEC and LNEC samples. Specific genes for each site were revealed: gastric NEC ( TERT amplification), colorectal NEC ( KRAS mutation), and bile tract NEC ( ARID1A mutation). The gene disparities between small-cell NEC (SCNEC) and large-cell NEC (LCNEC) were KEAP1 and CDH1. Digestive adenocarcinoma was also compared with GEPNEC and suggested RB1, APC, and KRAS as significant genes. The TP53/ RB1 mutation pattern was associated with first-line effectiveness. Putative targetable genes and biomarkers in GEPNEC were identified in 22.2% of the patients, and they had longer progression-free survival (PFS) upon targetable treatment [12.5 months vs. 3.0 months, HR=0.40 (0.21-0.75), P=0.006]. Conclusions: This work demonstrated striking gene distinctions in GEPNEC compared with LNEC and adenocarcinoma and their clinical utility.

7.
Lancet Oncol ; 24(10): 1134-1146, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37797632

RESUMEN

BACKGROUND: Immune checkpoint inhibitors targeting PD-1 or CTLA-4 individually have shown substantial clinical benefits in the treatment of malignancies. We aimed to assess the safety and antitumour activity of cadonilimab monotherapy, a bispecific PD-1/CTLA-4 antibody, in patients with advanced solid tumours. METHODS: This multicentre, open-label, phase 1b/2 trial was conducted across 30 hospitals in China. Patients aged 18 years or older with histologically or cytologically confirmed, unresectable advanced solid tumours, unsuccessful completion of at least one previous systemic therapy, and an Eastern Cooperative Oncology Group performance status of 0 or 1 were eligible for inclusion. Patients who had previously received anti-PD-1, anti-PD-L1, or anti-CTLA-4 treatment were not eligible for inclusion. In the dose escalation phase of phase 1b, patients received intravenous cadonilimab at 6 mg/kg and 10 mg/kg every 2 weeks. In the dose expansion phase of phase 1b, cadonilimab at 6 mg/kg and a fixed dose of 450 mg were given intravenously every 2 weeks. In phase 2, cadonilimab at 6 mg/kg was administered intravenously every 2 weeks in three cohorts: patients with cervical cancer, oesophageal squamous cell carcinoma, and hepatocellular carcinoma. The primary endpoints were the safety of cadonilimab in phase 1b and objective response rate in phase 2, based on the Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1. The safety analysis was done in all patients who received at least one dose of cadonilimab. Antitumour activity was assessed in the full analysis set for the cervical cancer cohort, and in all patients with measurable disease at baseline and who received at least one dose of cadonilimab in the oesophageal squamous cell carcinoma and hepatocellular carcinoma cohorts. The study is registered on ClinicalTrial.gov, NCT03852251, and closed to new participants; follow-up has been completed. FINDINGS: Between Jan 18, 2019, and Jan 8, 2021, 240 patients (83 [43 male and 40 female] in phase 1b and 157 in phase 2) were enrolled. Phase 2 enrolled 111 female patients with cervical cancer, 22 patients with oesophageal squamous cell carcinoma (15 male and seven female), and 24 patients with hepatocellular carcinoma (17 male and seven female). During dose escalation, no dose-limiting toxicities occurred. Grade 3-4 treatment-related adverse events occurred in 67 (28%) of 240 patients; the most frequent grade 3 or worse treatment-related adverse events were anaemia (seven [3%]), increased lipase (four [2%]), decreased bodyweight (three [1%]), decreased appetite (four [2%]), decreased neutrophil count (three [1%]), and infusion-related reaction (two [1%]). 17 (7%) patients discontinued treatment due to treatment-related adverse events. 54 (23%) of 240 patients reported serious treatment-related adverse events, including five patients who died (one due to myocardial infarction; cause unknown for four). In phase 2, in the cervical cancer cohort, with a median follow-up of 14·6 months (IQR 13·1-17·5), the objective response rate was 32·3% (32 of 99; 95% CI 23·3-42·5). In the oesophageal squamous cell carcinoma cohort, with a median follow-up of 17·9 months (IQR 4·0-15·1), the objective response rate was 18·2% (four of 22; 95% CI 5·2-40·3). In the hepatocellular carcinoma cohort, with a median follow-up of 19·6 months (IQR 8·7-19·8), the objective response rate was 16·7% (four of 24; 95% CI 4·7-37·4). INTERPRETATION: Cadonilimab showed an encouraging tumour response rate, with a manageable safety profile, suggesting the potential of cadonilimab for the treatment of advanced solid tumours. FUNDING: Akeso Biopharma. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Asunto(s)
Antineoplásicos Inmunológicos , Carcinoma Hepatocelular , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Neoplasias Hepáticas , Neoplasias del Cuello Uterino , Humanos , Masculino , Femenino , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Antígeno CTLA-4 , Receptor de Muerte Celular Programada 1 , Empatía , Anticuerpos Monoclonales Humanizados , Antineoplásicos Inmunológicos/efectos adversos , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/inducido químicamente , Neoplasias Hepáticas/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
8.
Anal Chem ; 2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36629754

RESUMEN

Programmed cell death (PCD) is a precisely controlled physiological process to sustain tissue homeostasis. Even though the PCD pathways have been explicitly subdivided, the individual cell death process seems to synergistically operate to eliminate cells rather than separately execute signal transduction. Apoptosis is the dominant intracellular PCD subtype, which is intimately regulated and controlled by mitochondria, thus tracing mitochondrial actions could reveal the dynamic changes of apoptosis, which may provide important tools for screening preclinical therapeutic agents. Herein, we exploited an innovative fluorophore Cy496 based on the light-initiated cleavage reaction. Cy496 bears the typical D-π-A structure and serves as a versatile building block for chemosensor construction through flexible side chains. By regulating lipophilicity and basicity through bis-site substitution, we synthesized a series of fluorescence probes and screened a novel mitochondria-targeted ratiometric probe Cy1321, which can real-time evaluate the dynamic changes of mitochondrial micropolarity mediated by bis-cholesterol anchoring. Cy1321 has realized two-color quantification and real-time visualization of polarity fluctuations on chemotherapy agent (cisplatin)-induced apoptosis through flow cytometry and confocal imaging and also achieved the purpose of detecting mitochondria-related apoptosis at the level of tissues. It is envisioned that Cy1321 has sufficient capability as a promising and facile tool for the evaluation of apoptosis and contributing to therapeutic drug screening.

9.
Anal Chem ; 95(46): 17089-17098, 2023 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-37940603

RESUMEN

Molecular diffusion and leakage impede the long-term retention of probes/drugs and may cause potential adverse effects in theranostic fields. Spatiotemporally manipulating the organelle-immobilization behavior of probes/drugs for prolonged tumor retention is indispensable to achieving effective cancer diagnosis and therapy. Herein, we propose a rational strategy that could realize near-infrared light-activated ribonucleic acids (RNAs) cross-linking for prolonged tumor retention and simultaneously endogenous hydrogen sulfide (H2S) monitoring in colorectal tumors. Profiting from efficient singlet oxygen (1O2) generation from Cy796 under 808 nm light irradiation, the 1O2-animated furan moiety in Cy796 could covalently cross-link with cytoplasmic RNAs via a cycloaddition reaction and realize organelle immobilization. Subsequently, specific thiolysis of Cy796 assisted with H2S resulted in homologous product Cy644 with reduced 1O2 generation yields and enhanced absolute fluorescence quantum yields (from 7.42 to 27.70%) with blue-shifted absorption and emission, which avoided the molecular oxidation fluorescence quenching effect mediated by 1O2 and validated fluorescence imaging. Furthermore, studies have demonstrated that our proposed strategy possessed adequate capacity for fluorescence imaging and endogenous H2S detection in HCT116 cells, particularly accumulated at the tumor sites, and retained long-term imaging with excellent biocompatibility. The turn-on fluorescence mode and turn-off 1O2 generation efficiency in our strategy successfully realized a diminished fluorescence cross-talk and oxidation quenching effect. It is adequately envisioned that our proposed strategy for monitoring biomarkers and prolonged tumor retention will contribute tremendous dedication in the clinical, diagnostic, and therapeutic fields.


Asunto(s)
Neoplasias Colorrectales , Sulfuro de Hidrógeno , Humanos , ARN Mitocondrial , Colorantes Fluorescentes , Neoplasias Colorrectales/diagnóstico por imagen , Imagen Óptica/métodos
10.
Eur Radiol ; 33(1): 380-390, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35927466

RESUMEN

OBJECTIVE: To investigate the performance of quantitative CT analysis in predicting the prognosis of patients with locally advanced oesophageal squamous cell carcinoma (ESCC) after two cycles of induction chemotherapy before definitive chemoradiotherapy/radiotherapy. METHODS: A total of 110 patients with locally advanced ESCC were retrospectively analysed. Baseline chest CT and CT after two cycles of induction chemotherapy were analysed. A multivariate Cox proportional-hazard regression model was used to identify independent prognostic markers for survival analysis. Then, a CT scoring system was established. Time-dependent receiver operating characteristic (ROC) curve analysis and the Kaplan-Meier method were employed for analysing the prognostic value of the CT scoring system. RESULTS: Body mass index, treatment strategy, change ratios of thickness (ΔTHmax), CT value of the primary tumour (ΔCTVaxial) and the short diameter (ΔSD-LN), and the presence of an enlarged small lymph node (ESLN) after two cycles of chemotherapy were noted as independent factors for predicting overall survival (OS). The specificity of the presence of ESLN for death after 12 months was up to 100%. Areas under the curve value of the CT scoring system for predicting OS and progression-free survival (PFS) were higher than that of the RECIST (p < 0.05). Responders had significantly longer OS and PFS than non-responders. CONCLUSION: Quantitative CT analysis after two cycles of induction chemotherapy could predict the outcome of locally advanced ESCC patients treated with definitive chemoradiotherapy/radiotherapy. The CT scoring system could contribute to the development of an appropriate strategy for patients with locally advanced ESCC. KEY POINTS: • Quantitative CT evaluation after two cycles of induction chemotherapy can predict the long-term outcome of locally advanced oesophageal cancer treated with definitive chemoradiotherapy/radiotherapy. • A CT scoring system provides valuable imaging support for indicating the prognosis at the early stage of therapy. • Quantitative CT evaluation can assist clinicians in personalising treatment plans.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/diagnóstico por imagen , Carcinoma de Células Escamosas de Esófago/terapia , Quimioterapia de Inducción , Estudios Retrospectivos , Quimioradioterapia , Pronóstico , Tomografía Computarizada por Rayos X , Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/terapia
11.
Heart Vessels ; 38(1): 40-48, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35915265

RESUMEN

This study was designed to assess coronary microvascular obstruction (MVO) in patients with acute ST-segment elevation myocardial infarction (STEMI) by cardiac magnetic resonance T2-weighted short tau inversion recovery (T2-STIR) image and layer-specific analysis of 2-dimensional speckle tracking echocardiography combined with low-dose dobutamine stress echocardiography (LDDSE-LS2D-STE). 32 patients were enrolled to perform cardiac magnetic resonance and echocardiography 5-7 days after primary percutaneous coronary intervention. Infarcted myocardium was categorized into MVO+ group and MVO- group by late gadolinium enhancement as gold standard. At T2-weighted image, the area of hyper-intense region and hypo-intense core inside were marked as A1, A2 and A2/A1 > 0 represented MVO. Strain parameters were composed of longitudinal strain (LS), circumferential strain and radial strain at rest and dobutamine stress. There were 94 MVO+ segments, 136 MVO- segments according to gold standard. 96 segments had hypo-intense core at T2-STIR image. The sensitivity and specificity of T2-STIR in detecting MVO were 91.49 and 92.65%. Endocardial LS was superior to other parameters, and stress endocardial LS was higher than that of resting endocardial LS (sensitivity: 77.11% vs 72.29%, specificity: 93.28% vs 83.19%, AUC: 0.87 vs 0.82, P < 0.05). The combination of T2-STIR and stress endocardial LS in parallel test could improve sensitivity significantly (98.05% vs 91.49%). T2-STIR has higher diagnostic value in detecting MVO with some limitations. However, LDDSE-LS2D-STE with cost-effective and handling may be a good alternative to T2-STIR. It provides additional and reliable diagnostic tools to identify MVO in STEMI patients after reperfusion.


Asunto(s)
Oclusión Coronaria , Infarto del Miocardio , Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST , Humanos , Infarto del Miocardio con Elevación del ST/diagnóstico , Infarto del Miocardio con Elevación del ST/terapia , Ecocardiografía de Estrés , Infarto del Miocardio/patología , Medios de Contraste , Gadolinio , Ecocardiografía/métodos , Espectroscopía de Resonancia Magnética , Imagen por Resonancia Cinemagnética
12.
Sensors (Basel) ; 23(14)2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37514625

RESUMEN

China is the largest producer and consumer of rice, and the classification of filled/unfilled rice grains is of great significance for rice breeding and genetic analysis. The traditional method for filled/unfilled rice grain identification was generally manual, which had the disadvantages of low efficiency, poor repeatability, and low precision. In this study, we have proposed a novel method for filled/unfilled grain classification based on structured light imaging and Improved PointNet++. Firstly, the 3D point cloud data of rice grains were obtained by structured light imaging. And then the specified processing algorithms were developed for the single grain segmentation, and data enhancement with normal vector. Finally, the PointNet++ network was improved by adding an additional Set Abstraction layer and combining the maximum pooling of normal vectors to realize filled/unfilled rice grain point cloud classification. To verify the model performance, the Improved PointNet++ was compared with six machine learning methods, PointNet and PointConv. The results showed that the optimal machine learning model is XGboost, with a classification accuracy of 91.99%, while the classification accuracy of Improved PointNet++ was 98.50% outperforming the PointNet 93.75% and PointConv 92.25%. In conclusion, this study has demonstrated a novel and effective method for filled/unfilled grain recognition.

13.
J Am Chem Soc ; 144(51): 23691-23697, 2022 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-36520955

RESUMEN

Free phosphaborenes (R-P═B-R) are PB analogues of alkynes, and their isolation is a long-sought-after goal. Herein, we demonstrate that the combination of a π-donating and a π-accepting substituent with bulky flanking arene rings enables the isolation of a crystalline free phosphaborene 5 at room temperature. This electron push-pull cooperation, combined with the kinetic protection, hinders its inherent tendency to oligomerize. This species features a PB double bond consisting of a conventional σ bond and a delocalized π bond. The lone pair of electrons at P slightly contributes to the PB bonding. Preliminary reactivity studies show that 5 undergoes facile (cyclo)addition reactions with p-methyl benzaldehyde, p-fluoroacetophenone, and carbon disulfide, the last of which results in facile PB double bond cleavage. Our strategy has a significant impact on the future synthesis of ambiphilic heterodiatomic multiply bonded main group species.


Asunto(s)
Alquinos , Electrones , Temperatura , Alquinos/química
14.
Cancer Immunol Immunother ; 71(1): 111-120, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34028566

RESUMEN

Immunotherapy has emerged as an effective therapeutic strategy for various cancers, including colorectal cancer (CRC), but only a subset of MSI-H patients can benefit from such therapy. Patched1 (PTCH1) is a frequently altered gene in CRCs and its mutations contribute to unregulated Hedgehog (Hh) signaling. In the study, we evaluated the association of PTCH1 mutations with CRC immunity based on our single-center cohort and multiple cancer genomic datasets. Among 21 enrolled patients, six (28.6%) harbored a PTCH1 mutation based on WES analyses. In CRC patients, the PTCH1 mutation subgroup experienced a higher durable clinical benefit rate than the PTCH1 wild-type subgroup (100% vs. 40%, P = 0.017). In addition, patients with the PTCH1 mutation experienced greater progression-free survival (PFS, P = 0.037; HR, 0.208) and overall survival (OS, P = 0.045; HR, 0.185). A validation cohort from the MSKCC also confirmed the correlation between PTCH1 mutation and better prognosis (P = 0.022; HR, 0.290). Mechanically, diverse antitumor immune signatures were more highly enriched in PTCH1-mutated tumors than in PTCH1 wild-type tumors. Furthermore, PTCH1-mutated tumors had higher proportions of CD8 + T cells, activated NK cells, and M1 type macrophage infiltration, as well as elevated gene signatures of several steps in the cancer-immunity cycle. Notably, the PTCH1 mutation was correlated with tumor mutational burden (TMB), loss of heterozygosity score, and copy number variation burden. Our results show that the mutation of PTCH1 is a potential biomarker for predicting the response of CRC patients to immunotherapy.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Colorrectales/inmunología , Inhibidores de Puntos de Control Inmunológico/química , Mutación , Receptor Patched-1/genética , Adolescente , Adulto , Anciano , Biomarcadores de Tumor , Antígeno CTLA-4/inmunología , Variaciones en el Número de Copia de ADN , Análisis Mutacional de ADN , Femenino , Genómica , Proteínas Hedgehog/genética , Humanos , Inmunoterapia/métodos , Macrófagos/metabolismo , Masculino , Inestabilidad de Microsatélites , Persona de Mediana Edad , Pronóstico , Supervivencia sin Progresión , Estudios Retrospectivos , Adulto Joven
15.
BMC Cancer ; 22(1): 355, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35365123

RESUMEN

BACKGROUND: We aimed to investigate response and prognostic factors in patients with human epidermal growth factor receptor 2 (HER2) positive metastatic colorectal cancer (mCRC) and compare the curative effect on patients who received different therapy regimens (including chemotherapy and chemotherapy combined with targeted drugs). METHODS: We retrospectively analyzed all HER2 positive mCRC patients treated at Peking University Cancer Hospital between September 2011 and February 2021. We divided 63 HER2 positive mCRC into group A and group B according to the use of trastuzumab or not. Besides, we assigned four subgroups according to the first-line therapies of KRAS/NRAS/BRAF WT patients. The Kaplan-Meier estimator was used to calculate PFS and OS. Univariable analysis and Cox proportional hazards models were used to analyze the association between clinicopathological features and survival outcomes. RESULTS: Among 63 patients, 54 (85.7%) were KRAS/NRAS/BRAF wild-type (WT). Univariate analysis showed that the male sex, primary lesions in the right colon, simultaneous metastasis, and unresectable primary lesions were significant risk factors for poor survival of HER2 positive mCRC (P < 0.05). Using Cox proportional hazards models, we found that the two factors of gender and resection of primary lesions were independent prognostic factors (P < 0.05). The median PFS and median OS of HER2-positive patients with mCRC who received first-line treatment were 8.4 months [95% confidence interval (CI): 5.0-11.7] and 48.2 months (95% CI: 23.5-72.8), respectively. The log-rank test revealed a significant difference in median OS survival between group A and group B (χ2 = 5.852, P = 0.016), and the two groups were divided according to the use or absence of trastuzumab treatment. In KRAS/NRAS/BRAF WT patients, there was a significant difference in median PFS and median OS between the fourth group patients (chemotherapy plus trastuzumab) and each of the other three groups (P < 0.05). CONCLUSIONS: The two factors of gender and resection for primary lesion may be independent prognostic factors of advanced HER2 positive colorectal cancer patients. For patients with HER2-positive mCRC, patients in the chemotherapy combined with trastuzumab group have better efficacy than those without trastuzumab.


Asunto(s)
Neoplasias Colorrectales , Receptor ErbB-2 , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Humanos , Masculino , Modelos de Riesgos Proporcionales , Receptor ErbB-2/uso terapéutico , Estudios Retrospectivos
16.
Gastric Cancer ; 25(5): 943-955, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35778636

RESUMEN

BACKGROUND: In solid tumor Phase 1/2 trials (NCT02407990; NCT04068519), tislelizumab demonstrated clinical benefit, including in advanced gastroesophageal adenocarcinoma (GEA). However, the majority of patients with GEA did not respond, highlighting the need to understand mechanisms of resistance and identify predictive biomarkers for response. METHODS: All tislelizumab-treated patients with GEA from the Phase 1/2 trials were included (N = 105). Programmed death-ligand 1 (PD-L1) expression (Tumor Area Positivity [TAP] ≥ 5%), interferon gamma (IFNγ)-related gene signature, gene expression profile, tumor mutational burden (TMB), and gene hyperamplification (HA) were analyzed for correlation with tislelizumab. RESULTS: A moderate association was observed between PD-L1 TAP ≥ 5%, IFNγ gene signature, TMB-high and efficacy. A potential correlation between hyperamplification (HA +) and worse outcomes with programmed cell death protein 1 (PD-1) inhibition was identified. Hyperamplified genes were mainly enriched in cancer progression pathways, including cell cycle and RTK-RAS-PI3K pathways. Joint PD-L1 TAP ≥ 5% and lack of hyperamplification showed the most favorable benefit with an objective response rate of 29.4%, and median progression-free survival and overall survival of 4.1 and 14.7 months, respectively. Tumors with TAP ≥ 5% and HA - had inflamed immune signatures with increased immune cell infiltration, enhanced anti-tumor cytotoxic activity and antigen presentation signatures. Findings were validated in two independent gastric and gastrointestinal cancer cohorts treated with immune checkpoint inhibitors. CONCLUSIONS: In GEA, PD-L1 positivity, IFNγ-related gene signature and TMB-high status were positively associated with tislelizumab clinical benefit, whereas HA was associated with worse clinical outcomes. Combining PD-L1 positivity and HA - may help identify patients more likely to benefit from PD-1 blockade.


Asunto(s)
Adenocarcinoma , Neoplasias Pulmonares , Neoplasias Gástricas , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/genética , Anticuerpos Monoclonales Humanizados , Antígeno B7-H1 , Biomarcadores de Tumor/genética , Ensayos Clínicos Fase I como Asunto , Ensayos Clínicos Fase II como Asunto , Neoplasias Esofágicas , Unión Esofagogástrica/patología , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Mutación , Fosfatidilinositol 3-Quinasas/genética , Receptor de Muerte Celular Programada 1/genética , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética
17.
J Sci Food Agric ; 102(8): 3435-3445, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34837649

RESUMEN

BACKGROUND: Molluscan shellfish, including oysters, often cause allergic reactions in sensitive people throughout the world. It has been demonstrated that arginine kinase (AK) is one of the major allergens of oyster. The present study aimed to evaluate the immunoreactivity and structure of oyster AK as affected by heat treatment, pH change, and in vitro digestion. What is more, the immunoglobulin E-binding epitopes of this allergen were also predicted and validated. RESULTS: Thermal and pH assays revealed that AK was unstable at temperature >40 °C or pH ≤5.0 by sodium dodecyl sulfate polyacrylamide gel electrophoresis and circular dichroism, and the digestibility assays suggested that AK was more easily digested by pepsin than by trypsin and chymotrypsin. The potential epitopes were predicted through immunoinformatics tools, and seven linear epitopes were identified by indirect competition enzyme-linked immunosorbent assay with pooled sera and individual serum from oyster-allergic patients. The critical amino acids in each epitope were also confirmed using mutant peptides. These linear epitopes and critical amino acids were apt to distribute on the outer surface of homology-based AK model. Moreover, the three denaturants (sodium dodecyl sulfate, ß-mercaptoethanol, and urea) can destroy the spatial structure of AK and increase or reduce its allergenicity by denaturation treatments. CONCLUSION: Processing conditions lay the foundation for the variation of allergenicity. Seven linear epitopes and their critical amino acids were identified by indirect competitive enzyme-linked immunosorbent assay. These findings will be helpful in allergy diagnosis and development of hypoallergenic products in the near future. © 2021 Society of Chemical Industry.


Asunto(s)
Arginina Quinasa , Crassostrea , Alérgenos/química , Secuencia de Aminoácidos , Aminoácidos , Animales , Arginina Quinasa/química , Arginina Quinasa/metabolismo , Epítopos/química , Humanos , Dodecil Sulfato de Sodio
18.
Clin Immunol ; 212: 108345, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31953149

RESUMEN

BACKGROUND: Biomarkers in non-colorectal gastrointestinal (GI) cancer patients receiving immune checkpoint blockades (ICBs) are still limited. METHODS: Data were prospectively collected from a discovery cohort (n = 53) and a validation cohort (n = 107) in patients with non-colorectal GI cancer receiving ICB, as well as a chemotherapy-only cohort (n = 171). System inflammatory markers and derived neutrophil-to-lymphocyte ratio (dNLR) were determined as biomarkers by univariate and multivariate analyses. RESULTS: A higher level of dNLR (cutoff = 3) was associated with shorter overall survival (OS) in discovery and validation cohorts. In pooled cohort, disease control rate (DCR) (28% vs. 48.1%) was associated with dNLR (p = .017). In univariate analysis, original tumor site, tumor histopathology, number of metastases, and dNLR were correlated with OS. In multivariate analysis, higher dNLR level was correlated with reduced OS (10.43 months vs. 4.20 months, p < .001). In chemotherapy-only cohort, dNLR was also correlated with DCR and OS. CONCLUSION: Higher dNLR level was correlated with worse outcomes, suggesting that dNLR may help risk-group stratification and assist disease management strategies as a prognostic biomarker for non-colorectal GI patients receiving ICB.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Antineoplásicos Inmunológicos/uso terapéutico , Carcinoma de Células Escamosas/tratamiento farmacológico , Neoplasias Esofágicas/tratamiento farmacológico , Recuento de Linfocitos , Neutrófilos , Neoplasias Gástricas/tratamiento farmacológico , Adenocarcinoma/sangre , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/metabolismo , Biomarcadores , Antígeno CTLA-4/antagonistas & inhibidores , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/patología , Neoplasias del Sistema Digestivo/sangre , Neoplasias del Sistema Digestivo/tratamiento farmacológico , Neoplasias del Sistema Digestivo/patología , Neoplasias Esofágicas/sangre , Neoplasias Esofágicas/patología , Femenino , Neoplasias de la Vesícula Biliar/sangre , Neoplasias de la Vesícula Biliar/tratamiento farmacológico , Neoplasias de la Vesícula Biliar/patología , Humanos , Recuento de Leucocitos , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Masculino , Inestabilidad de Microsatélites , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pronóstico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Supervivencia sin Progresión , Estudios Retrospectivos , Neoplasias Gástricas/sangre , Neoplasias Gástricas/patología , Tasa de Supervivencia , Adulto Joven
19.
Med Sci Monit ; 26: e924671, 2020 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-33077705

RESUMEN

BACKGROUND Despite the promising results of immunotherapy in cancer treatment, new response patterns, including pseudoprogression and hyperprogression, have been observed. Radiomics is the automated extraction of high-fidelity, high-dimensional imaging features from standard medical images, allowing comprehensive visualization and characterization of the tissue of interest and corresponding microenvironment. This study assessed whether radiomics can predict response to immunotherapy in patients with malignant tumors of the digestive system. MATERIAL AND METHODS Computed tomography (CT) images of patients with malignant tumors of the digestive system obtained at baseline and after immunotherapy were subjected to radiomics analyses. Radiomics features were extracted from each image. The formula of the screened features and the final predictive model were obtained using the Least Absolute Shrinkage and Selection Operator (LASSO) algorithm. RESULTS Imaging analysis was feasible in 87 patients, including 3 with pseudoprogression and 7 with hyperprogression. One hundred ten radiomics features were obtained before and after treatment, including 109 features of the target lesions and 1 of the aorta. Four models were constructed, with the model constructed from baseline and post-treatment CT features having the best classification performance, with a sensitivity, specificity, and AUC of 83.3%, 88.9%, and 0.806, respectively. CONCLUSIONS Radiomics can predict the response of patients with malignant tumors of the digestive system to immunotherapy and can supplement conventional evaluations of response.


Asunto(s)
Carcinoma , Neoplasias del Sistema Digestivo , Tomografía Computarizada por Rayos X , Carcinoma/diagnóstico por imagen , Carcinoma/terapia , Neoplasias del Sistema Digestivo/diagnóstico por imagen , Neoplasias del Sistema Digestivo/terapia , Femenino , Humanos , Inmunoterapia , Masculino , Estudios Retrospectivos
20.
BMC Cancer ; 19(1): 705, 2019 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-31315610

RESUMEN

BACKGROUND: Immune checkpoint inhibitors (ICIs) were approved to have a significant antitumor activity in various tumor types. In practice, some patients do not seem to benefit from ICIs but rather to have accelerating disease. The aim of this study was to evaluate hyperprogression in patients with malignant tumors of digestive system treated with ICIs. METHODS: Medical records from consecutive patients with malignant tumors of digestive system treated with ICIs in Peking University Cancer Hospital were retrospectively collected. Tumor growth kinetics (TGK) on immunotherapy and TGK pre-immunotherapy were collected and TGK ratio (TGKR) was calculated. Hyperprogression was defined as TGKR≥2. RESULTS: From August 2016 to May 2017, 25 evaluable patients were identified from 45 patients with malignant tumors of digestive system. Five patients were considered as having hyperprogression. Three of 5 were neuroendocrine carcinomas (NECs) and the other 2 were adenocarcinomas. Four of 5 were treated with programmed cell death ligand 1 (PD-L1) inhibitor, the other one was treated with PD-L1 inhibitor combined with cytotoxic T lymphocyte associated antigen-4 (CTLA-4) inhibitor. Pseudoprogression was observed in 2 patients. CONCLUSIONS: Hyperprogression was observed in a fraction of patients with malignant tumors of digestive system treated with ICIs. Further investigation is urgently needed.


Asunto(s)
Adenocarcinoma/terapia , Carcinoma Neuroendocrino/terapia , Neoplasias del Sistema Digestivo/terapia , Progresión de la Enfermedad , Inmunoterapia/efectos adversos , Adulto , Anciano , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/farmacología , Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos/efectos adversos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antígeno B7-H1/antagonistas & inhibidores , Antígeno CTLA-4/antagonistas & inhibidores , Quimioterapia Combinada , Resultado Fatal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
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