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1.
EClinicalMedicine ; 73: 102656, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38828130

RESUMO

Background: Gastrointestinal stromal tumors (GISTs) represent the most prevalent type of subepithelial lesions (SELs) with malignant potential. Current imaging tools struggle to differentiate GISTs from leiomyomas. This study aimed to create and assess a real-time artificial intelligence (AI) system using endoscopic ultrasonography (EUS) images to differentiate between GISTs and leiomyomas. Methods: The AI system underwent development and evaluation using EUS images from 5 endoscopic centers in China between January 2020 and August 2023. EUS images of 1101 participants with SELs were retrospectively collected for AI system development. A cohort of 241 participants with SELs was recruited for external AI system evaluation. Another cohort of 59 participants with SELs was prospectively enrolled to assess the real-time clinical application of the AI system. The AI system's performance was compared to that of endoscopists. This study is registered with Chictr.org.cn, Number ChiCT2000035787. Findings: The AI system displayed an area under the curve (AUC) of 0.948 (95% CI: 0.921-0.969) for discriminating GISTs and leiomyomas. The AI system's accuracy (ACC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) reached 91.7% (95% CI 87.5%-94.6%), 90.3% (95% CI 83.4%-94.5%), 93.0% (95% CI 87.2%-96.3%), 91.9% (95% CI 85.3%-95.7%), and 91.5% (95% CI 85.5%-95.2%), respectively. Moreover, the AI system exhibited excellent performance in diagnosing ≤20 mm SELs (ACC 93.5%, 95% CI 0.900-0.969). In a prospective real-time clinical application trial, the AI system achieved an AUC of 0.865 (95% CI 0.764-0.966) and 0.864 (95% CI 0.762-0.966) for GISTs and leiomyomas diagnosis, respectively, markedly surpassing endoscopists [AUC 0.698 (95% CI 0.562-0.834) for GISTs and AUC 0.695 (95% CI 0.546-0.825) for leiomyomas]. Interpretation: We successfully developed a real-time AI-assisted EUS diagnostic system. The incorporation of the real-time AI system during EUS examinations can assist endoscopists in rapidly and accurately differentiating various types of SELs in clinical practice, facilitating improved diagnostic and therapeutic decision-making. Funding: Science and Technology Commission Foundation of Shanghai Municipality, Science and Technology Commission Foundation of the Xuhui District, the Interdisciplinary Program of Shanghai Jiao Tong University and the Research Funds of Shanghai Sixth people's Hospital.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38940773

RESUMO

Objective: The objective of this study is to develop a prediction model for the pathological upgrading of low-grade dysplasia (LGD) in gastric mucosa. The study aims to compare the performance of a traditional model based on clinical and endoscopic factors with an enhanced model that incorporates AMACR staining of biopsy tissues. Methods: The study utilized a training dataset of 405 LGD cases to establish and compare the traditional and enhanced prediction models. Factors associated with upgrading were identified, and the traditional model was based on these factors. The enhanced model incorporated AMACR staining. The models' performances were evaluated using the area under the curve (AUC), bootstrap resampling, and decision curve analysis. External validation was performed using 171 LGD cases. Statistical techniques such as logistic regression and resampling methods were employed to assess the models' predictive abilities and robustness. Results: In the training dataset, the traditional model achieved an AUC of 0.824 (95% confidence interval [CI]: 0.783-0.865) for predicting pathological upgrading. However, the enhanced model, which incorporated AMACR staining, exhibited a significantly improved performance with an AUC of 0.878 (95% CI: 0.843-0.913). This increase in AUC by 0.054 (95% CI: 0.015-0.093) demonstrates a statistically significant enhancement provided by the inclusion of AMACR staining in the prediction model for pathological upgrading of LGD lesions in gastric mucosa. Conclusion: The findings of this study highlight the practical implications of the enhanced prediction model incorporating AMACR staining for low-grade gastric mucosal dysplasia (LGD). The significantly improved performance of the enhanced model in predicting pathological upgrading emphasizes its potential to revolutionize the management and treatment strategies for patients with LGD. By providing a more accurate prediction of upgrading, the enhanced model enables early intervention and timely decision-making, leading to improved outcomes and prognosis for patients. The incorporation of AMACR staining in the prediction model holds promise for enhancing diagnostic strategies and reducing the incidence of postoperative pathological upgrading. This research underscores the importance of leveraging advanced techniques to improve the early detection rate of gastric cancer and ultimately benefit patient care.

4.
Langmuir ; 39(36): 12649-12661, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37651421

RESUMO

Noncovalent interactions play a crucial role in driving the formation of diverse self-assembled structures in surfactant systems. Surfactants containing a benzene ring structure are an important subset of surfactants. These surfactants exhibit unique colloid and interfacial properties, which give rise to fascinating transformations in the aggregate structures. These transformations are directly influenced by specific noncovalent interactions facilitated by the benzene ring structure including cation-π and π-π interactions. Investigating catanionic surfactant systems that incorporate benzene ring structures provides valuable insights into the distinct noncovalent interactions observed in mixed surfactant systems. Our approach involved studying the enthalpy change ΔH during the titration process, utilizing isothermal titration calorimetry (ITC). Simultaneously, we employed cryogenic transmission electron microscopy (cryo-TEM) to observe the corresponding self-assembly structures. To gain further insight, we delved into the noncovalent interactions of the mixed systems by analyzing the molecular environments variations through chemical shifts of the aggregates using proton magnetic resonance (1H NMR). The intermolecular interaction was also confirmed by the two-dimensional nuclear Overhauser enhancement spectroscopy (2D NOESY). We conducted a systematic study of the effects of NaCl concentrations, molar ratios, and molecular structures of surfactants on aggregate structures. The existence forms of surfactants are closely linked to the shape of the titration curve and the transition of the aggregate structures. When cationic surfactants were titrated into sodium dodecylbenzenesulfonate (SDBS) micelle solutions, the dominant cation-π interaction leads to the direct formation of vesicle structures. Conversely, when the SDBS system is titrated into benzyldimethyldodecylammonium chloride (DDBAC) micelles, a delicate balance of multiple noncovalent interactions, including cation-π, π-π, hydrophobic, and electrostatic forces, results in a range of aggregate structure transformations such as worm-like micelles and vesicular structures.

5.
Digestion ; 103(1): 69-75, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34666330

RESUMO

BACKGROUND: With the development of new technologies such as magnifying endoscopy with narrow band imaging, endoscopists achieved better accuracy for diagnosis of gastric cancer (GC) in various aspects. However, to master such skill takes substantial effort and could be difficult for inexperienced doctors. Therefore, a novel diagnostic method based on artificial intelligence (AI) was developed and its effectiveness was confirmed in many studies. AI system using convolutional neural network has showed marvelous results in the ongoing trials of computer-aided detection of colorectal polyps. SUMMARY: With AI's efficient computational power and learning capacities, endoscopists could improve their diagnostic accuracy and avoid the overlooking or over-diagnosis of gastric neoplasm. Several systems have been reported to achieved decent accuracy. Thus, AI-assisted endoscopy showed great potential on more accurate and sensitive ways for early detection, differentiation, and invasion depth prediction of gastric lesions. However, the feasibility, effectiveness, and safety in daily practice remain to be tested. Key messages: This review summarizes the current status of different AI applications in early GC diagnosis. More randomized controlled trails will be needed before AI could be widely put into clinical practice.


Assuntos
Neoplasias Gástricas , Inteligência Artificial , Endoscopia Gastrointestinal , Humanos , Imagem de Banda Estreita , Sobrediagnóstico , Neoplasias Gástricas/diagnóstico por imagem
6.
ACS Med Chem Lett ; 11(9): 1766-1772, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32944145

RESUMO

Efforts aimed at increasing the in vivo potency and reducing the elimination half-life of 1 and 2 led to the identification of aryl ether and thioether-derived bicyclic S1P1 differentiated modulators 3-6. The effects of analogs 3-6 on lymphocyte reduction in the rat (desired pharmacology) along with pulmonary- and cardiovascular-related effects (undesired pharmacology) are described. Optimization of the overall properties in the aryl ether series yielded 3d, and the predicted margin of safety against the cardiovascular effects of 3d would be large enough for human studies. Importantly, compared to 1 and 2, compound 3d had a better profile in both potency (ED50 < 0.05 mg/kg) and predicted human half-life (t 1/2 ∼ 5 days).

7.
Oncol Lett ; 13(5): 3379-3386, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28521443

RESUMO

Previous studies have investigated the mechanisms of immune evasion of tumor cells in numerous types of advanced solid malignant tumor, and several types of immune preparations have been administered as antitumor adjuvant therapies. However, in the majority of studies, the efficacy of therapies has been revealed to be limited. The present study aimed to investigate the immune evasion mechanisms employed by early colorectal cancer cells and the expression of the molecules associated with immune evasion during the malignant transformation process of normal colorectal epithelial cells to measure the effects of immune intervention for early colorectal cancer, and to improve the efficacy of immunotherapy. A total of 60 colorectal tissues, including 15 normal mucosa, 15 adenoma, 15 early cancer and 15 advanced cancer tissues, from patients undergoing endoscopic procedures in Huadong Hospital Affiliated to Fudan University (Shanghai, China) were collected. A comparison of baseline characteristics among these four groups was performed. The expression levels of human leukocyte antigen-A (HLA-A), apoptosis antigen 1 (Fas), c-c chemokine receptor type 5 (CCR5), Fas ligand (FasL) and HLA-E in each group were detected by immunohistochemical analysis. Furthermore, 15 patients with advanced colorectal cancer were enrolled into the present study. Advanced cancer and paracancer tissues (normal mucosal tissues 3 cm away from the margin of cancer tissues) were collected from each patient by colonoscopic biopsy. The expression levels of HLA-A, Fas, CCR5, FasL and HLA-E in each group were detected by western blot analysis. During the malignant transformation process of normal colorectal epithelial cells, the expression levels of CCR5, FasL and HLA-E increased significantly (P<0.001), whilst the expression levels of Fas reduced significantly (P=0.0271). In the early cancer group, the expression levels of Fas reduced significantly (P=0.0239), whilst the expression levels of HLA-E increased significantly (P<0.001) compared with adenoma group. In conclusion, a loss of Fas expression and high expression levels of HLA-E may promote the immune evasion of early colorectal cancer cells.

8.
Bioorg Med Chem Lett ; 23(24): 6902-4, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24169233

RESUMO

Anti-microtubule agents such as paclitaxel and docetaxel have played an important role in the treatment of cancer for many years. Recently, a small molecule that has a taxol-like mode of action (5HPP-33) was reported. Herein, the detailed structure-activity relationship (SAR) studies of 5HPP-33 analogs that are substituted at the isoindole and phenyl rings are described. Bulky substitutions (such as di-isopropyl groups) on the phenyl ring result in the isoindole and phenyl rings being perpendicular to each other. It was found that this conformation is critical for anti-microtubule activity. These studies have provided valuable information, which will be helpful in the design of more potent analogs.


Assuntos
Isoindóis/química , Microtúbulos/química , Paclitaxel/química , Talidomida/análogos & derivados , Talidomida/farmacologia , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Isoindóis/síntese química , Isoindóis/farmacologia , Microtúbulos/metabolismo , Relação Estrutura-Atividade , Talidomida/síntese química , Moduladores de Tubulina/síntese química
9.
Anticancer Res ; 27(6B): 3801-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18225535

RESUMO

BACKGROUND: The mammary glands of adult female animals are remarkably sensitive to keratinocyte growth factor (KGF). KGF acts at the KGF receptor (KGFR) to produce a rapid and profound stimulation of breast cancer cell proliferation and motility. Further, KGF-induced motility in breast cancer cells is mediated via the Erk1/2 signaling pathway. Thus, enhancement of KGF/KGFR signal transduction may be an early step in the metastatic progression of breast cancer. Receptor modeling of KGFR was used to identify selective KGFR tyrosine kinase inhibitor (TKI) molecules with high receptor affinity. The present study describes the synthesis and biological activity of three of the KGFR TKI compounds. MATERIALS AND METHODS: Computer modeling of the KGFR was used to create a virtual library of compounds that have the potential to bind with high affinity to the KGFR. Three of these compounds were synthesized and tested in this study. The compounds were tested for their ability to inhibit KGF-mediated breast cancer cell proliferation and motility using a culture wounding assay. In addition, the effect of the most potent KGFR TKI compound on the relative density of cell membrane KGFR was measured using immunocytochemistry. RESULTS: It was observed that the KGFR TKIs decreased KGF-mediated activity as predicted by computer modeling. In addition, the most potent inhibitor also reduced the density of the KGFR on the membrane of the cancer cells. CONCLUSION: The novel inhibitors identified in this project are selective KGFR inhibitors which appear to reduce the expression of KGFR on cancer cells. These results may lead to the development of a novel class of anticancer agents for the chemoprevention of metastatic cancer development and provide a new approach in the treatment of breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Desenho de Fármacos , Humanos , Imuno-Histoquímica , Quinolonas/síntese química , Quinolonas/farmacologia
10.
Bioorg Med Chem Lett ; 15(24): 5382-5, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16213720

RESUMO

A series of compounds originally derived from the vascular endothelial growth factor receptor tyrosine kinase inhibitor, SU5416, was synthesized and evaluated. The most potent compound in this series, compound 7, structurally resembles the potent anti-microtubule agent Combretastatin A-4, inhibited tubulin polymerization, and showed potent growth inhibitory activities on both prostate and breast cancer lines with IC(50) values in low to subnanomolar range.


Assuntos
Indóis/química , Pirróis/química , Estilbenos/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Divisão Celular/efeitos dos fármacos , Modelos Moleculares , Conformação Molecular , Suínos , Tubulina (Proteína)/efeitos dos fármacos , Tubulina (Proteína)/metabolismo
11.
Bioorg Med Chem Lett ; 13(6): 1187-9, 2003 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-12643940

RESUMO

The synthesis and anti-angiogenic activities of linomide and its analogues are reported. Three of the analogues are 3.3-69 times more potent than linomide at inhibiting blood vessel formation in the CAM angiogenesis assay. These compounds possessed considerable anti-proliferative activity against isolated HUVEC cells with no activity against epithelial-derived prostate tumor cells.


Assuntos
Inibidores da Angiogênese/síntese química , Inibidores da Angiogênese/farmacologia , Hidroxiquinolinas/síntese química , Hidroxiquinolinas/farmacologia , Alantoína/química , Animais , Divisão Celular/efeitos dos fármacos , Embrião de Galinha , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Humanos , Masculino , Membranas/efeitos dos fármacos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Neoplasias da Próstata/irrigação sanguínea , Neoplasias da Próstata/patologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
12.
Steroids ; 67(10): 821-6, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12231117

RESUMO

The enzyme steryl sulfatase may help support the growth of hormone-dependent tumors, including prostate cancers, by facilitating the conversion of circulating precursor steroids to active hormones. We sought to determine the presence of steryl sulfatase activity in the androgen-dependent human prostate cancer cell line LNCaP, and to determine if this activity was inhibited by known steryl sulfatase inhibitors. Intact LNCaP cultures had steryl sulfatase activity, as determined by conversion of [3H]estrone sulfate (E(1)S) to unconjugated steroids. The level of steryl sulfatase activity was relatively low (4.6 pmol/18 h/million cells) compared to MDA-MB-231 breast cancer cells (284.0 pmol/18 h/million cells). The observed activity in both cell lines was blocked by addition of 1 microM estrone sulfamate (EMATE), an active-site-directed, steroidal inhibitor of steryl sulfatase. Steryl sulfatase activity was also inhibited by Danazol, and by (p-O-sulfamoyl)-tetradecanoyl tyramine (C2-14), a non-steroidal inhibitor. Microsomes prepared from LNCaP cultures also showed steryl sulfatase activity, as determined by hydrolysis of [3H]E(1)S and [3H]dehydroepiandrosterone sulfate (DHEAS) to unconjugated forms. LNCaP and MDA-MB-231 microsomes both hydrolyzed E(1)S about two times faster than DHEAS. Hydrolysis of E(1)S in LNCaP and MDA-MB-231 microsomes was blocked by steryl sulfatase inhibitors with the following relative potencies: EMATE>C2-14>Danazol. These data demonstrate that LNCaP prostate cancer cells contain a steryl sulfatase with properties similar to that found in human breast cancer cells, and that the activity of this enzyme can be blocked by known steryl sulfatase inhibitors. Steryl sulfatase inhibitors may be useful as an adjuvant to androgen deprivation therapy for prostate cancer.


Assuntos
Arilsulfatases/antagonistas & inibidores , Estrona/análogos & derivados , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/patologia , Tiramina/análogos & derivados , Arilsulfatases/metabolismo , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Danazol/farmacologia , Sulfato de Desidroepiandrosterona/metabolismo , Inibidores Enzimáticos/farmacologia , Estrona/metabolismo , Estrona/farmacologia , Feminino , Humanos , Cinética , Masculino , Microssomos/metabolismo , Esteril-Sulfatase , Sulfonamidas/farmacologia , Células Tumorais Cultivadas , Tiramina/farmacologia
13.
Biol Pharm Bull ; 25(5): 597-604, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12033499

RESUMO

Angiogenesis, in particular anti-angiogenesis, is an area of particular therapeutic interest in cancer treatment. Several anti-angiogenic agents are in the final stages of clinical trials. One of these agents, thalidomide, best known for its teratogenic potential, is showing promise against several tumor types. Thalidomide has been shown previously to require bio-activation to exert its anti-angiogenic effect in isolated blood vessels and endothelial cells. In this work, we confirmed these findings using the in utero chicken embryo chorioallantoic membrane (CAM) system. In particular, the anti-angiogenic effect of thalidomide is significantly enhanced by activation by human but not by rat liver microsomes. We also showed in the CAM assay that hydroxylation of thalidomide at either the 1'- or 5-position retained anti-angiogenic activity whereas its hydroxylation at the 4-position led to an inactive compound. We further demonstrated that thalidomide shows weak anti-proliferative activity against MDA-MB-231 human breast cancer cells in culture. Thalidomide showed slightly more anti-proliferative activity, however, against the SH-SY5Y human neuroblastoma and human umbilical vein endothelial cell (HUVEC) types. Furthermore, incubation of thalidomide with human liver microsomes added no additional anti-proliferative effect in these cell types versus thalidomide given alone. Finally, we report that none of the thalidomide metabolites tested had any anti-proliferative effect against the breast or neuroblastoma cells, but do possess appreciable anti-proliferative activity against the endothelial cells. In summary, this work suggests that hydroxylated thalidomide analogs based on putative metabolites of the drug possess significant anti-angiogenic activity and that exploring further derivatives of these as potential anti-angiogenic agents warrants further merit.


Assuntos
Inibidores da Angiogênese , Vasos Sanguíneos/efeitos dos fármacos , Córion/irrigação sanguínea , Endotélio Vascular/citologia , Talidomida/farmacologia , Animais , Antimetabólitos/farmacologia , Bromodesoxiuridina/farmacologia , Divisão Celular/efeitos dos fármacos , Embrião de Galinha , Endotélio Vascular/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Humanos , Hidroxilação , Técnicas In Vitro , Microssomos Hepáticos/metabolismo , Ratos , Fluxo Sanguíneo Regional , Talidomida/metabolismo , Células Tumorais Cultivadas
14.
J Comb Chem ; 4(2): 149-53, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11886289

RESUMO

A novel solid-phase synthesis of thalidomide and its metabolites and analogues is described. The synthetic strategy involves the coupling of hydroxymethyl polystyrene with phthalic anhydride to form the resin-linked acid. The acid is then reacted with primary amines followed by acid or base treatment to form thalidomide and its analogues with either open or closed phthalimide rings. Most of the analogues are synthesized with high yields (40.3-98.1% in three steps) and purities (92.3-98.9%).


Assuntos
Inibidores da Angiogênese/síntese química , Talidomida/análogos & derivados , Talidomida/síntese química , Técnicas de Química Combinatória , Humanos , Talidomida/farmacologia
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