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1.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33602823

RESUMO

Many cancers evade immune rejection by suppressing major histocompatibility class I (MHC-I) antigen processing and presentation (AgPP). Such cancers do not respond to immune checkpoint inhibitor therapies (ICIT) such as PD-1/PD-L1 [PD-(L)1] blockade. Certain chemotherapeutic drugs augment tumor control by PD-(L)1 inhibitors through potentiation of T-cell priming but whether and how chemotherapy enhances MHC-I-dependent cancer cell recognition by cytotoxic T cells (CTLs) is not entirely clear. We now show that the lysine acetyl transferases p300/CREB binding protein (CBP) control MHC-I AgPPM expression and neoantigen amounts in human cancers. Moreover, we found that two distinct DNA damaging drugs, the platinoid oxaliplatin and the topoisomerase inhibitor mitoxantrone, strongly up-regulate MHC-I AgPP in a manner dependent on activation of nuclear factor kappa B (NF-κB), p300/CBP, and other transcription factors, but independently of autocrine IFNγ signaling. Accordingly, NF-κB and p300 ablations prevent chemotherapy-induced MHC-I AgPP and abrogate rejection of low MHC-I-expressing tumors by reinvigorated CD8+ CTLs. Drugs like oxaliplatin and mitoxantrone may be used to overcome resistance to PD-(L)1 inhibitors in tumors that had "epigenetically down-regulated," but had not permanently lost MHC-I AgPP activity.


Assuntos
Apresentação de Antígeno/imunologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Antígenos de Histocompatibilidade Classe I/imunologia , Inibidores de Checkpoint Imunológico/farmacologia , NF-kappa B/metabolismo , Neoplasias/tratamento farmacológico , Fatores de Transcrição de p300-CBP/metabolismo , Animais , Antineoplásicos/farmacologia , Apoptose , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linfócitos T CD8-Positivos , Proliferação de Células , Quimioterapia Combinada , Humanos , Imunoterapia/métodos , Camundongos , NF-kappa B/genética , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Oxaliplatina/farmacologia , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Fatores de Transcrição de p300-CBP/genética
2.
Biochem Biophys Res Commun ; 464(1): 118-25, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26106824

RESUMO

After demonstrating bradykinin (BK) could increase the permeability of blood-tumor barrier (BTB) via opening the tight junction (TJ), and that the possible mechanism is unclear, we demonstrated that BK could increase the expressions of eNOS and nNOS and promote ZONAB translocation into nucleus. NOS inhibitors l-NAME and 7-NI could effectively block the effect of BK on increasing BTB permeability, decreasing the expressions of claudin-5 and occludin and promoting the translocation of ZONAB. Overexpression of ZONAB could significantly enhance BK-mediating BTB permeability. Meanwhile, chromatin immunoprecipitation verified ZONAB interacted with the promoter of claudin-5 and occludin respectively. This study indicated NOS/NO/ZONAB pathway might be involved in BK's increasing the permeability of BTB.


Assuntos
Bradicinina/farmacologia , Neoplasias Encefálicas/metabolismo , Regulação Neoplásica da Expressão Gênica , Glioma/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico/metabolismo , Vasodilatadores/farmacologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Claudina-5/antagonistas & inibidores , Claudina-5/genética , Claudina-5/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Glioma/genética , Glioma/patologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase Tipo I/genética , Óxido Nítrico Sintase Tipo III/genética , Ocludina/antagonistas & inibidores , Ocludina/genética , Ocludina/metabolismo , Permeabilidade/efeitos dos fármacos , Regiões Promotoras Genéticas , Ligação Proteica , Transporte Proteico , Ratos , Ratos Wistar , Transdução de Sinais , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
Adv Sci (Weinh) ; : e2402450, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38952061

RESUMO

Discovering new treatments for melanoma will benefit human health. The mechanism by which deoxyhypusine synthase (DHPS) promotes melanoma development remains elucidated. Multi-omics studies have revealed that DHPS regulates m6A modification and maintains mRNA stability in melanoma cells. Mechanistically, DHPS activates the hypusination of eukaryotic translation initiation factor 5A (eIF5A) to assist METTL3 localizing on its mRNA for m6A modification, then promoting METTL3 expression. Structure-based design, synthesis, and activity screening yielded the hit compound GL-1 as a DHPS inhibitor. Notably, GL-1 directly inhibits DHPS binding to eIF5A, whereas GC-7 cannot. Based on the clarification of the mode of action of GL-1 on DHPS, it is found that GL-1 can promote the accumulation of intracellular Cu2+ to induce apoptosis, and antibody microarray analysis shows that GL-1 inhibits the expression of several cytokines. GL-1 shows promising antitumor activity with good bioavailability in a xenograft tumor model. These findings clarify the molecular mechanisms by which DHPS regulates melanoma proliferation and demonstrate the potential of GL-1 for clinical melanoma therapy.

4.
Mol Ther Oncolytics ; 28: 212-229, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36860815

RESUMO

Breast cancer is the leading cause of cancer-related deaths in females worldwide, and the liver is one of the most common sites of distant metastases in breast cancer patients. Patients with breast cancer liver metastases face limited treatment options, and drug resistance is highly prevalent, leading to a poor prognosis and a short survival. Liver metastases respond extremely poorly to immunotherapy and have shown resistance to treatments such as chemotherapy and targeted therapies. Therefore, to develop and to optimize treatment strategies as well as to explore potential therapeutic approaches, it is crucial to understand the mechanisms of drug resistance in breast cancer liver metastases patients. In this review, we summarize recent advances in the research of drug resistance mechanisms in breast cancer liver metastases and discuss their therapeutic potential for improving patient prognoses and outcomes.

5.
Antiviral Res ; 219: 105720, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37748652

RESUMO

Immune checkpoint blockade-based therapies are effective against a sorts of cancers. However, drug resistance is a problem that cannot be ignored. This review intends to elucidate the mechanisms underlying drug tolerance induced by PD-1/PD-L1 inhibitors, as well as to outline proposed mechanism-based combination therapies and small molecule drugs that target intrinsic immunity and immune checkpoints. According to the differences of patients and types of cancer, the optimization of individualized combination therapy will help to enhance PD-1/PD-L1-mediated immunoregulation, reduce chemotherapy resistance, and provide new ideas for chemotherapy-resistant cancer.


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Receptor de Morte Celular Programada 1 , Neoplasias/tratamento farmacológico
6.
Mol Ther Oncolytics ; 31: 100752, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38130701

RESUMO

Extracellular vesicles (EVs) carry DNA, RNA, protein, and other substances involved in intercellular crosstalk and can be used for the targeted delivery of drugs. Triple-negative breast cancer (TNBC) is rich in recurrent and metastatic disease and lacks therapeutic targets. Studies have proved the role of EVs in the different stages of the genesis and development of TNBC. Cancer cells actively secrete various biomolecules, which play a significant part establishing the tumor microenvironment via EVs. In this article, we describe the roles of EVs in the tumor immune microenvironment, metabolic microenvironment, and vascular remodeling, and summarize the application of EVs for objective delivery of chemotherapeutic drugs, immune antigens, and cancer vaccine adjuvants. EVs-based therapy may represent the next-generation tool for targeted drug delivery for the cure of a variety of diseases lacking effective drug treatment.

7.
Front Cell Dev Biol ; 10: 893490, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35784467

RESUMO

Small-cell lung cancer (SCLC) is a highly proliferative, invasive lung cancer with poor prognosis. Chemotherapy is still the standard first-line treatment for SCLC, but many patients relapse due to chemoresistance. Along with advances in immunology, it is essential to investigate potential indicators of the immune response and the prognosis of SCLC. Using bioinformatics analysis, we identified 313 differentially expressed genes (DEGs) in SCLC and normal lung samples, and we found that four upregulated genes (TOP2A, CDKN2A, BIRC5, and MSH2) were associated with platinum resistance, while immune-related genes (HLA family genes) were downregulated in SCLC. Then, a prognostic prediction model was constructed for SCLC based on those genes. Immune cell infiltration analysis showed that antigen presentation was weak in SCLC, and TOP2A expression was negatively correlated with CD8+ T cells, while HLA-ABC expression was positively correlated with M1 macrophages, memory B cells, and CD8+ T cells. We also found that TOP2A was related to poor prognosis and inversely correlated with HLA-ABC, which was verified with immunohistochemical staining in 151 SCLC specimens. Our study findings indicated that TOP2A may be a potential prognosis indicator and a target to reverse the immunosuppressive tumor microenvironment of SCLC.

8.
Br J Nutr ; 99(6): 1330-4, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17961293

RESUMO

We aimed to describe the vitamin D status of young women living in two Chinese cities in the spring--Beijing in the north (latitude 39 degrees north) and Hong Kong (latitude 22 degrees north) in the south. We also examined the relationship between serum 25-hydroxyvitamin D and parathyroid hormone (PTH) concentrations to determine a threshold for serum 25-hydroxyvitamin D above which there is no further suppression of PTH. Finally, we examined whether dietary Ca intake influences this relationship. Non-pregnant women aged 18-40 years (n 441) were recruited between February and June. Fasting blood was collected and dietary intakes were assessed using 5 d food records. Mean serum 25-hydroxyvitamin D concentration was lower in Beijing than Hong Kong women (29 v. 34 nmol/l; P < 0.001). Vitamin D deficiency (< or = 25 nmol/l) was indicated in 40% of Beijing and 18% of Hong Kong women, and over 90% of women in both cities were insufficient (< or = 50 nmol/l). Mean Ca and vitamin D intakes were 478 mg/d and 2.0 microg/d, respectively. The relationship between 25-hydroxyvitamin D concentration and PTH was linear throughout the range with a slope of -0.36 (different from 0; P < 0.001; R 0.26), with no apparent threshold. There was no influence of Ca intake on the relationship between 25-hydroxyvitamin D and PTH concentration. Vitamin D deficiency is common and insufficiency is very common in non-pregnant women in Hong Kong and Beijing during spring. Serum 25-hydroxyvitamin D was inversely associated with PTH with no apparent threshold. Strategies such as vitamin D fortification or supplementation may be required.


Assuntos
Estações do Ano , Deficiência de Vitamina D/epidemiologia , Adulto , Cálcio da Dieta/administração & dosagem , China/epidemiologia , Registros de Dieta , Feminino , Hong Kong/epidemiologia , Humanos , Modelos Lineares , Estado Nutricional , Hormônio Paratireóideo/sangue , Prevalência , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/sangue
9.
Zhonghua Liu Xing Bing Xue Za Zhi ; 33(10): 1031-5, 2012 Oct.
Artigo em Zh | MEDLINE | ID: mdl-23290845

RESUMO

OBJECTIVE: To understand the intention on marriage and the related influence factors among men who have sex with men (MSM). METHODS: Using the snowball sampling method, an anonymous questionnaire survey was achieved by recruiting MSM. RESULTS: A total number of 308 people were included in this survey, the numbers of 'planning to get married' was 34.4%, intended not to get married accounted for 65.6%; and the average age of intending to marry was (28.1 ± 3.3) years old. The intended marriage partners were ordinary women accounted for 83.8%, while another 16.2% were lesbians. Reasons for getting married were under social pressure (65.1%), under family pressure (12.3%), and under personal desire (22.6%). Those who intended to remain contact with gay after marriage accounted for 66.7%, with 16.2% did not and those were not sure accounted for 17.1%. Using the multivariate analysis method, results showed that the independent factors for intention of marriage were: age, sexual orientation, registration for residency, cumulative numbers of regular sexual partners, number of anal sex in the last week, proportion of intention to get married was relatively low among those who were over 35 years of age and their residence of registration were in the city. However those who were bisexual, with uncertain sexual orientation, and with low cumulative numbers of regular sexual partners as well as less anal sex in the past week, occupied higher proportions. CONCLUSION: MSM population under our current study showed a high percentage on marriage intention which posed serious challenges to the society and families. AIDS prevention on this population seemed to be impacted by demographic characteristics and sexual behavior.


Assuntos
Homossexualidade Masculina/psicologia , Intenção , Casamento/psicologia , Pessoa Solteira , Adolescente , Adulto , China/epidemiologia , Fatores Epidemiológicos , Humanos , Masculino , Adulto Jovem
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