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1.
Apoptosis ; 23(5-6): 255-264, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29556906

RESUMO

As an evolutionarily conserved serine/threonine kinase of the phosphoinositide 3-kinase (PI3K) related kinase family, the mechanistic/mammalian target of rapamycin (mTOR) plays vital roles in the PI3K/AKT/mTOR pathway, participating in different cellular processes including cell survival, metabolism and proliferation. Aberrant activity of this signaling pathway may lead to oncogenesis. Over the last two decades, great progress has been made in the understanding of mTOR activation and how its response is counteracted for maintaining tissue homeostasis. Besides regulatory proteins and microRNAs, long noncoding RNA (lncRNA) is another emerging critical layer of the intricate modulatory architecture for the control of the mTOR signaling circuit. Also, the production of numerous lncRNAs is induced by mTOR treatment. These findings offer new perspectives for designing novel diagnostic and therapeutic strategies. In this review, we summarize the interactions between the mTOR signaling pathway and lncRNAs in the development and progression of various types of tumors, focusing on the mechanisms of these interactions, and also discuss the potential use of lncRNAs as biomarkers and therapeutic targets for malignancies.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias/metabolismo , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Antineoplásicos/farmacologia , Humanos , Neoplasias/tratamento farmacológico
2.
Entropy (Basel) ; 20(6)2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-33265529

RESUMO

Automatic question answering (QA), which can greatly facilitate the access to information, is an important task in artificial intelligence. Recent years have witnessed the development of QA methods based on deep learning. However, a great amount of data is needed to train deep neural networks, and it is laborious to annotate training data for factoid QA of new domains or languages. In this paper, a distantly supervised method is proposed to automatically generate QA pairs. Additional efforts are paid to let the generated questions reflect the query interests and expression styles of users by exploring the community QA. Specifically, the generated questions are selected according to the estimated probabilities they are asked. Diverse paraphrases of questions are mined from community QA data, considering that the model trained on monotonous synthetic questions is very sensitive to variants of question expressions. Experimental results show that the model solely trained on generated data via the distant supervision and mined paraphrases could answer real-world questions with the accuracy of 49.34%. When limited annotated training data is available, significant improvements could be achieved by incorporating the generated data. An improvement of 1.35 absolute points is still observed on WebQA, a dataset with large-scale annotated training samples.

3.
Sci Rep ; 14(1): 2367, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287125

RESUMO

Multiple primary cancer (MPC) denotes individuals with two or more malignant tumors occurring simultaneously or successively. Herein, a total of 11,000 pancancer patients in TCGA database (1993-2013) were divided into MPC or non-MPC groups based on their history of other malignant tumors. The incidence of MPC has risen to 8.5-13.1% since 2000. Elderly individuals, males, early-stage cancer patients, and African Americans and Caucasians are identified as independent risk factors (p < 0.0001). Non-MPC patients exhibit significantly longer overall survival (OS) and disease-free survival (DFS) (p = 0.0038 and p = 0.0014). Age (p < 0.001) and tumor staging at initial diagnosis (p < 0.001) contribute to this difference. In our center, MPC was identified in 380 out of 801 tumor events based on SEER criteria. The peak occurrence of secondary primary was about 1-5 years after the first primary tumor, with a second small peak around 10-15 years. Multiple tumors commonly occur in the same organ (e.g., breast and lung), constituting 12.6%. Certain cancer types, notably skin cutaneous melanoma (SKCM), exhibit significantly higher tumor mutational burden (TMB) in the MPC group (17.31 vs. 6.55 mutations/MB, p < 0.001), with high TMB associated with improved survival (p < 0.001). High TMB in MPC may serve as a predictor for potential immunotherapy application.


Assuntos
Melanoma , Neoplasias Primárias Múltiplas , Neoplasias Cutâneas , Masculino , Humanos , Idoso , Melanoma/patologia , Neoplasias Cutâneas/patologia , Estadiamento de Neoplasias , Genômica , Neoplasias Primárias Múltiplas/epidemiologia , Mutação , Biomarcadores Tumorais
4.
Front Oncol ; 12: 841977, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371995

RESUMO

Background: Programmed death receptor-1 (PD-1) blockade shows little benefit in patients with microsatellite-stable colorectal cancer (MSS-CRC). Fruquintinib is a China-made anti-angiogenic drug which is approved for the third line therapy in mCRC. This study investigates the effect of the combination of fruquintinib and PD-1 blockade on MSS-CRC and its relative mechanisms. Methods: The mouse allograft tumor models that represent MSS and microsatellite instability (MSI) CRC were established using murine CT26 and MC38 colon cancer cells, respectively, to assess the treatment efficacy. The percentages of immune cells were detected in the peripheral blood, spleen and tumor tissues in the tumor-bearing mice by flow cytometry analysis. Angiogenesis in tumor tissues was detected by immunofluorescence. The safety of drug treatment was evaluated by histopathology analysis in murine main organs. The efficacy of the combination of fruquintinib and sintilimab were verified in the treatment of MSS-CRC patients. Results: Our results showed that the combination of fruquintinib and sintilimab exhibited the strongest inhibition of tumor growth and achieved the longest survival time in mice bearing MC38 or CT26 xenograft tumors, compared to fruquintinib and sintilimab alone. Mechanistically, the combination of fruquintinib and sintilimab reduced angiogenesis, reprogramed the vascular structure, enhanced the infiltration of CD8+T cells (p<0.05), CD8+TNFα+ (p<0.05) T cells and CD8+IFNγ+ (p<0.05) T cells and reduced the ratios of MDSCs and macrophages in mice. There was no obvious toxicity observed in the main organs of the tumor-bearing mice with the combined treatment. Moreover, the treatment using the combination of fruquintinib and sintilimab achieved effective response in five patients with refractory advanced MSS CRC. Conclusion: Our results show that the combination of fruquintinib and sintilimab greatly inhibits CRC growth by altering tumor immune microenvironment. This study provides the rational for using the combination of fruquintinib and anti-PD-1 antibody for the treatment of advanced CRC.

5.
Oncoimmunology ; 11(1): 2131084, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36268178

RESUMO

Myeloid-derived suppressor cells (MDSCs) have been demonstrated to suppress antitumor immunity and induce resistance to PD-1/PD-L1 blockade immunotherapy in gastric and colon cancer patients. Herein, we found that MDSCs accumulate in mice bearing syngeneic gastric cancer and colon cancer. Death receptor 5 (DR5), a receptor of TNF-related apoptosis-inducing ligand (TRAIL), was highly expressed on MDSCs and cancer cells; targeting DR5 using agonistic anti-DR5 antibody (MD5-1) specifically depleted MDSCs and induced enrichment of CD8+ T lymphocytes in tumors and exhibited stronger tumor inhibition efficacy in immune-competent mice than in T-cell-deficient nude mice. Importantly, the combination of MD5-1 and anti-PD-L1 antibody showed synergistic antitumor effects in gastric and colon tumor-bearing mice, resulting in significantly suppressed tumor growth and extended mice survival, whereas single-agent treatment had limited effect. Moreover, the combination therapy induced sustained memory immunity in mice that exhibited complete tumor regression. The enhanced antitumor effect was associated with increased intratumoral CD8+ T-cell infiltration and activation, and a more vigorous tumor-inhibiting microenvironment. In summary, our findings highlight the therapeutic potential of combining PD-L1 blockade therapy with agonistic anti-DR5 antibody that targets MDSCs in gastric and colon cancers.


Assuntos
Neoplasias do Colo , Células Supressoras Mieloides , Camundongos , Animais , Células Supressoras Mieloides/patologia , Receptor de Morte Celular Programada 1 , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Camundongos Nus , Receptores do Ligante Indutor de Apoptose Relacionado a TNF , Microambiente Tumoral , Neoplasias do Colo/tratamento farmacológico
6.
Bioact Mater ; 6(7): 2158-2172, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33511314

RESUMO

Tumor vasculature constitutes a formidable hurdle for the efficient delivery of cancer nanomedicine into tumors. The leverage of passive pathway through inter-endothelial gaps in tumor blood vessels might account for limited extravasation of nanomedicine into tumor microenvironment (TME). Herein, Annexin A1 antibody-installed mesoporous organosilica nanoplatforms carrying immunotherapeutics of anti-PD-L1 antibody (aPD-L1) and Indoximod are developed to target at caveolar Annexin-A1 protein of luminal endothelial cells and to trigger the active trans-endothelial transcytosis of nanomedicine mediated by caveolae. Such strategy enables rapid nanomedicine extravasation across tumor endothelium and relatively extensive accumulation in tumor interstitium. aPD-L1 and Indoximod release from aPD/IND@MON-aANN in a reduction-responsive manner and synergistically facilitate the intratumoral infiltration of cytotoxic T lymphocytes and reverse the immunosuppressive TME, thus demonstrating substantial anti-tumor efficacy in subcutaneous 4T1 breast tumors and remarkable anti-metastatic capacity to extend the survival of 4T1 tumor metastasis model. Moreover, aPD/IND@MON-aANN nanomedicine also exhibits distinct superiority over the combination therapy of free drugs to potently attenuate the progression of urethane-induced orthotopic lung cancers. Collectively, aPD/IND@MON-aANN nanoplatforms with boosted delivery efficiency via antibody-activated trans-endothelial pathway and enhanced immunotherapeutic efficacy provides perspectives for the development of cancer nanomedicines.

7.
Cell Death Dis ; 12(4): 338, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795638

RESUMO

Utidelone (UTD1), a novel microtubule stabilizing agent, is an epothilone B analogue which was produced by genetic engineering. UTD1 has exhibited broad antitumor activity in multiple solid tumors. However, its activity and mechanism in colorectal cancer (CRC) remain to be studied. In this study, UTD1 dramatically inhibited CRC cell proliferation (with 0.38 µg/ml, 0.77 µg/ml IC50 in RKO and HCT116, respectively) in vitro. Immunofluorescence staining showed that UTD1 induced the formation of microtubule bundling and asters in RKO cells. Flow cytometry analysis demonstrated that UTD1 induced cell cycle to arrest in G2/M phase, subsequent apoptosis. Significantly, UTD1 exhibited stronger effect on inducing apoptosis than paclitaxel and 5-FU, especially in HCT15 cells which is ABCB1 high-expression. UTD1 exposure cleaved caspase-3 and poly ADP-ribose polymerase (PARP), decreased mitochondrial membrane potential, released cytochrome c, increased the production of active oxygen and activated c-Jun N-terminal kinase (JNK), suggesting ROS/JNK pathway was involved in this process. Moreover, UTD1 inhibited tumor growth and was more effective and safer compared with paclitaxel and 5-FU in RKO xenograft in nude mice. Taken together, our findings first indicate that UDT1 inhibits tumor growth in CRC xenograft model and may be a promising agent for CRC treatment.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Epotilonas/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Nus , Paclitaxel/farmacologia
8.
Front Immunol ; 12: 619209, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33790893

RESUMO

Cancer-associated fibroblasts (CAFs) has been recognized as one cause of tumor resistance to immune checkpoint blockade therapy, but the underlying mechanisms still remain elusive. In the present study, a bone marrow-derived CAF (BMF) -rich tumor model is successfully established by subcutaneously mixed inoculation of BMFs and tumor cells into mice and the BMF-mixed tumor xenografts are demonstrated to be resistant to anti-PD-L1 antibody immunotherapy compared to the mere tumor xenografts. In vitro assays via the co-culture system of BMFs and tumor cells indicate that the co-cultured BMFs are induced to overexpress PD-L1, while there is no such a phenomenon in the co-cultured cancer cells. The further knock-out of PD-L1 in BMFs rescues the sensitivity of BMF-mixed tumor xenografts to PD-L1 blockade therapy. Mechanistically, via the microarray assay, we identify that the upregulation of PD-L1 in BMFs stimulated by cancer cells is medicated by the activation of the Wnt/ß-catenin signaling pathway in BMFs. Moreover, the administration of Wnt/ß-catenin signaling inhibitors, including XAV-939 and Wnt-C59, distinctly inhibits the upregulation of PD-L1 expression in the co-cultured BMFs. The further combination administration of XAV-939 significantly potentiates the therapeutic outcome of PD-L1 blockade therapy in BMF-mixed tumors. In summary, our study demonstrates that Wnt inhibition augments PD-L1 blockade efficacy by overcoming BMF-mediated immunotherapy resistance.


Assuntos
Antígeno B7-H1/antagonistas & inibidores , Fibroblastos Associados a Câncer/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores de Checkpoint Imunológico/farmacologia , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Proteínas Wnt/antagonistas & inibidores , Animais , Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/patologia , Linhagem Celular Tumoral , Células Cultivadas , Modelos Animais de Doenças , Expressão Gênica , Genes Reporter , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Imuno-Histoquímica , Camundongos , Miofibroblastos/imunologia , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Via de Sinalização Wnt/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Cancer Lett ; 523: 182-194, 2021 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-34627950

RESUMO

Rab1A overexpression has been observed in several cancer types, however, its significance and the underlying mechanisms in non-small cell lung cancer (NSCLC) remain largely unexplored. This study demonstrated that Rab1A overexpression in NSCLC was significantly correlated to short survival and metastasis. Rab1A overexpression promoted cancer cell migration, invasion, and metastasis both in vitro and in vivo, by activating JAK1/STAT6 signaling through stabilizing IL-4Rα protein. Strikingly, high Rab1A level was associated with sensitivity to JAK1 inhibitor, and Rab1A overexpression rendered cancer cells vulnerable to JAK1-targeted agents. JAK1 inhibitor, Itacitinib adipate, dramatically inhibited high Rab1A NSCLC metastasis, in both cell line and patient derived xenograft models. Collectively, these findings demonstrated that Rab1A plays a critical role in the aggressive properties of NSCLC, revealing a unique mechanism by which it promotes metastasis. In addition, we found that Rab1A is a determinant of JAK1 inhibitor sensitivity, which could be explored for improving JAK1-targeted cancer therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Janus Quinase 1/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Receptores de Interleucina-4/fisiologia , Fator de Transcrição STAT6/fisiologia , Proteínas rab1 de Ligação ao GTP/fisiologia , Animais , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular , Humanos , Janus Quinase 1/fisiologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Invasividade Neoplásica , Metástase Neoplásica , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Cell Death Dis ; 11(10): 821, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009367

RESUMO

Dysregulation of free acid metabolism is a major contributor to the development of insulin resistance and diabetes. Mitochondrial trifunctional enzyme subunit (MTPα) has a critical role in fatty acid ß-oxidation. However, the association between MTPα and insulin resistance is not definitively known. Here, we aimed to determine how MTPα affects insulin resistance. We tested how MTPα affected glucose uptake in insulin-resistant 3T3-L1 adipocytes and white adipose tissue (WAT) of db/db diabetic mice. We also measured how acetylation and ubiquitylation modifications regulated MTPα activation and stability, using quantitative real-time polymerase chain reactions, immunoblotting, and immunoprecipitation. We found that MTPα overexpression promoted glucose uptake via Glut4 translocation to the plasma membrane in 3T3-L1 adipocytes. Moreover, MTPα upregulation decreased glycemia in db/db mice. Deacetylation increased MTPα protein stability and its ability to reduce insulin resistance. The activation of SIRT1, a major deacetylase, prevented MTPα degradation by decreasing its acetylation in adipocytes. Our study demonstrates a new role for MTPα in reducing insulin resistance. Acetylation and ubiquitylation modifications of MTPα were crucial to regulating its function in glucose metabolism.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo Branco/metabolismo , Resistência à Insulina/fisiologia , Sirtuína 1/metabolismo , Ubiquitinação/fisiologia , Células 3T3-L1 , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Camundongos
11.
Comput Intell Neurosci ; 2016: 3506261, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27698659

RESUMO

Word embedding, a lexical vector representation generated via the neural linguistic model (NLM), is empirically demonstrated to be appropriate for improvement of the performance of traditional language model. However, the supreme dimensionality that is inherent in NLM contributes to the problems of hyperparameters and long-time training in modeling. Here, we propose a force-directed method to improve such problems for simplifying the generation of word embedding. In this framework, each word is assumed as a point in the real world; thus it can approximately simulate the physical movement following certain mechanics. To simulate the variation of meaning in phrases, we use the fracture mechanics to do the formation and breakdown of meaning combined by a 2-gram word group. With the experiments on the natural linguistic tasks of part-of-speech tagging, named entity recognition and semantic role labeling, the result demonstrated that the 2-dimensional word embedding can rival the word embeddings generated by classic NLMs, in terms of accuracy, recall, and text visualization.


Assuntos
Linguística , Modelos Estatísticos , Semântica , Aprendizagem Verbal/fisiologia , Vocabulário , Simulação por Computador , Humanos
12.
Aging (Albany NY) ; 8(11): 2790-2798, 2016 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-27902464

RESUMO

Rab1A expression is associated with malignant phenotypes in several human tumors; however, the role of Rab1A in lung cancer is still unclear. In this study, we attempted to establish the role of Rab1A in major human lung cancer subtypes. Rab1A expression in different histological types of human lung cancer was analyzed in lung cancer tissues with paired adjacent noncancerous tissues and a large panel of lung cancer cell lines. The effect of Rab1A expression on multiple cancer-associated signaling pathways was also examined. The results demonstrated that Rab1A was significantly overexpressed in the different histological types of lung cancer as compared to non-cancerous tissues, and Rab1A expression was correlated with tumor volume and stage. In a large panel of lung cancer cell lines, high Rab1A expression was observed as compared to a normal lung/bronchus epithelial cell line. However, Rab1A protein levels were not correlated with mTORC1 (P-S6K1), mTORC2 (P-AKT), MEK (P-ERK), JNK (P-c-Jun) or p38MAPK (P-MK2) signaling. Rab1A knockdown had no effect on mTOR signaling or cell growth. These data suggested that Rab1A may be involved in the pathogenesis of human lung cancer in an mTOR- and MAPK-independent manner.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Transdução de Sinais , Proteínas rab1 de Ligação ao GTP/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Carcinoma Broncogênico/genética , Carcinoma Broncogênico/metabolismo , Carcinoma Broncogênico/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Serina-Treonina Quinases TOR , Proteínas rab1 de Ligação ao GTP/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-18002433

RESUMO

An structure is proposed for fabricating a portable prototype apparatus, using the embedded control technique based on ARM core, which has a simple structure and small size. The hardware is easily updated and maintained due to its modular structure, the software has a visualized interface and hierarchical design mode, so the apparatus has a good peculiarity like compact structure and control. Moreover, the build-in PID algorithm for temperature control and the power driver element for ultrasonic output power have been optimized the experiment results demonstrate that using this structure and optimization method. Due to the speed of data collecting by parallel interface is much quick than the speed of data collecting by serial interface, so a reliable performance of this apparatus can be achieved, which can meet with the need of clinical application.


Assuntos
Hipertermia Induzida/instrumentação , Hipertermia Induzida/métodos , Transdutores , Terapia por Ultrassom/instrumentação , Ultrassom , Algoritmos , Computadores , Compressão de Dados , Desenho de Equipamento , Modelos Estatísticos , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador , Software , Temperatura , Terapia por Ultrassom/métodos
14.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 6368-71, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17281724

RESUMO

High intensity focused ultrasound (HIFU) is one of promising non invasive thermal ablation techniques of tumor, and the demand of imaging for guidance the HIFU procedure is becoming important. We choose ultrasound imaging method based on sequence images to locate the focal position of the HIFU. To the characteristic of ultrasound sequence images, we adopt a diffusion stick method for speckle noise suppression in ultrasonic images, and improve the discrete active contour method by adding external force in segmenting sequence ultrasonic images. The experiments of clinical ultrasonic images show that the techniques are effective. The next work is to reconstruct the processed sequence images into volume data for visualization and guidance the therapy procedure.

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