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1.
Nature ; 615(7950): 158-167, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36634707

RESUMO

Despite the success of PD-1 blockade in melanoma and other cancers, effective treatment strategies to overcome resistance to cancer immunotherapy are lacking1,2. Here we identify the innate immune kinase TANK-binding kinase 1 (TBK1)3 as a candidate immune-evasion gene in a pooled genetic screen4. Using a suite of genetic and pharmacological tools across multiple experimental model systems, we confirm a role for TBK1 as an immune-evasion gene. Targeting TBK1 enhances responses to PD-1 blockade by decreasing the cytotoxicity threshold to effector cytokines (TNF and IFNγ). TBK1 inhibition in combination with PD-1 blockade also demonstrated efficacy using patient-derived tumour models, with concordant findings in matched patient-derived organotypic tumour spheroids and matched patient-derived organoids. Tumour cells lacking TBK1 are primed to undergo RIPK- and caspase-dependent cell death in response to TNF and IFNγ in a JAK-STAT-dependent manner. Taken together, our results demonstrate that targeting TBK1 is an effective strategy to overcome resistance to cancer immunotherapy.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Evasão da Resposta Imune , Imunoterapia , Proteínas Serina-Treonina Quinases , Humanos , Evasão da Resposta Imune/genética , Evasão da Resposta Imune/imunologia , Imunoterapia/métodos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Organoides , Fatores de Necrose Tumoral/imunologia , Interferon gama/imunologia , Esferoides Celulares , Caspases , Janus Quinases , Fatores de Transcrição STAT
2.
EMBO J ; 43(3): 391-413, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38225406

RESUMO

Cristae membrane state plays a central role in regulating mitochondrial function and cellular metabolism. The protein Optic atrophy 1 (Opa1) is an important crista remodeler that exists as two forms in the mitochondrion, a membrane-anchored long form (l-Opa1) and a processed short form (s-Opa1). The mechanisms for how Opa1 influences cristae shape have remained unclear due to lack of native three-dimensional views of cristae. We perform in situ cryo-electron tomography of cryo-focused ion beam milled mouse embryonic fibroblasts with defined Opa1 states to understand how each form of Opa1 influences cristae architecture. In our tomograms, we observe a variety of cristae shapes with distinct trends dependent on s-Opa1:l-Opa1 balance. Increased l-Opa1 levels promote cristae stacking and elongated mitochondria, while increased s-Opa1 levels correlated with irregular cristae packing and round mitochondria shape. Functional assays indicate a role for l-Opa1 in wild-type apoptotic and calcium handling responses, and show a compromised respiratory function under Opa1 imbalance. In summary, we provide three-dimensional visualization of cristae architecture to reveal relationships between mitochondrial ultrastructure and cellular function dependent on Opa1-mediated membrane remodeling.


Assuntos
Fibroblastos , Membranas Mitocondriais , Animais , Camundongos , Fibroblastos/metabolismo , Membranas Mitocondriais/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo
3.
Br J Cancer ; 130(9): 1463-1476, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38438589

RESUMO

BACKGROUND: Uterine serous cancer (USC) comprises around 10% of all uterine cancers. However, USC accounts for approximately 40% of uterine cancer deaths, which is attributed to tumor aggressiveness and limited effective treatment. Galectin 3 (Gal3) has been implicated in promoting aggressive features in some malignancies. However, Gal3's role in promoting USC pathology is lacking. METHODS: We explored the relationship between LGALS3 levels and prognosis in USC patients using TCGA database, and examined the association between Gal3 levels in primary USC tumors and clinical-pathological features. CRISPR/Cas9-mediated Gal3-knockout (KO) and GB1107, inhibitor of Gal3, were employed to evaluate Gal3's impact on cell function. RESULTS: TCGA analysis revealed a worse prognosis for USC patients with high LGALS3. Patients with no-to-low Gal3 expression in primary tumors exhibited reduced clinical-pathological tumor progression. Gal3-KO and GB1107 reduced cell proliferation, stemness, adhesion, migration, and or invasion properties of USC lines. Furthermore, Gal3-positive conditioned media (CM) stimulated vascular tubal formation and branching and transition of fibroblast to cancer-associated fibroblast compared to Gal3-negative CM. Xenograft models emphasized the significance of Gal3 loss with fewer and smaller tumors compared to controls. Moreover, GB1107 impeded the growth of USC patient-derived organoids. CONCLUSION: These findings suggest inhibiting Gal3 may benefit USC patients.


Assuntos
Proteínas Sanguíneas , Cistadenocarcinoma Seroso , Galectina 3 , Neoplasias Uterinas , Humanos , Feminino , Neoplasias Uterinas/patologia , Neoplasias Uterinas/genética , Neoplasias Uterinas/metabolismo , Galectina 3/genética , Galectina 3/metabolismo , Cistadenocarcinoma Seroso/patologia , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/metabolismo , Proliferação de Células , Linhagem Celular Tumoral , Prognóstico , Animais , Camundongos , Galectinas/genética , Galectinas/metabolismo , Movimento Celular
4.
J Immunol ; 202(6): 1704-1714, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30710045

RESUMO

Glycine is a simple nonessential amino acid known to have neuroprotective properties. Treatment with glycine results in reduced infarct volume of the brain, neurologic function scores, and neuronal and microglial death in ischemic stroke injury. Neuroinflammation has been considered a major contributor to cerebral ischemia-induced brain damage. However, the role of glycine in neuroinflammation following ischemic stroke is unclear. The present study aimed to determine whether neuroinflammation is involved in the neuroprotective effects of glycine in cerebral ischemia injury. Ischemic stroke promotes M1 microglial polarization. Interestingly, we found that the injection of glycine in rats after injury can inhibit ischemia-induced inflammation and promote M2 microglial polarization in vivo (Sprague-Dawley rats) and in vitro (cortical microglia and BV-2 cells). We show that glycine suppresses Hif-1α by inhibiting the upregulation of NF-κB p65 after ischemia-reperfusion injury, resulting in the inhibition of proinflammatory activity. The activation of AKT mediates the inhibition of NF-κB p65/Hif-1α signaling by glycine. Moreover, we confirm that glycine-regulated AKT activation is mediated by the inhibition of PTEN in a PTEN depletion cell line, U251 cells. Glycine modulates microglial polarization after ischemic stroke, which indirectly inhibits ischemia-induced neuronal death and functional recovery. Taken together, our findings provide a new understanding of glycine in neuroprotection by inhibiting M1 microglial polarization and promoting anti-inflammation by suppressing NF-κB p65/Hif-1α signaling.


Assuntos
Encéfalo/efeitos dos fármacos , Glicina/farmacologia , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Acidente Vascular Cerebral/imunologia , Animais , Encéfalo/imunologia , Encéfalo/patologia , Isquemia Encefálica/imunologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Feminino , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia , Fator de Transcrição RelA/metabolismo
5.
BMC Neurol ; 20(1): 149, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321464

RESUMO

BACKGROUND: Cavernous hemangioma of the orbit is a benign tumor mostly located behind the eye globe, but it rarely spread into the brain, which is called cerebral cavernous malformation as well, the lesion in the brain is irregular and enlarged blood. Here we report one particular case of craniorbital cavernous hemangioma. CASE PRESENTATION: A 53-year-old woman presented with exophthalmos of the right eye and reduced vision. Computerized tomographical (CT) scan showed osteolytic honeycomb radial changes of the outer plate of the skull. A magnetic resonance imaging (MRI) scan was performed to obtain further details. T1-weighted (T1W) imaging showed slightly low signal mixed with small patchy high signal. T2-weighted (T2W) imaging showed uneven high signal. There was obvious enhancement in the middle and no enhancement in the peripheral bars. A surgically manage was performed using a left frontotemporal approach, the tumor excised fully, and the histopathology results revealed a cavernous hemangioma. The patient recovered well in the follow-up. Post-operative CT scan identified the lesion was successfully resected, MRI scan also showed full resection and enhanced signal from the presence of fat. CONCLUSIONS: Craniorbital cavernous hemangioma is uncommon, however within the cranium, they can lead to numerous complications particularly if affecting the visual apparatus. it could be diagnosed by imaging, which CT scan shows osteolytic honeycomb radial changes of the outer plate of the skull, T1W imaging shows slightly low signal mixed with small patchy high signal, T2W imaging shows uneven high signal, it is obvious enhancement in the middle and no enhancement in the peripheral bars. The surgically manage is the ideally treatment when there are some symptoms.


Assuntos
Hemangioma Cavernoso , Órbita/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
6.
Neurochem Res ; 44(11): 2658-2669, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31612303

RESUMO

Subarachnoid hemorrhage (SAH) is a form of stroke associated with high mortality and morbidity. Despite advances in treatment for SAH, the prognosis remains poor. We have previously demonstrated that glycine, a non-essential amino acid is involved in neuroprotection following intracerebral hemorrhage via the Phosphatase and tensin homolog (PTEN)/protein kinase B (AKT) signaling pathway. However, whether it has a role in inducing neuroprotection in SAH is not known. The present study was designed to investigate the role of glycine in SAH. In this study, we show that glycine can reduce brain edema and protect neurons in SAH via a novel pathway. Following a hemorrhagic episode, there is evidence of downregulation of S473 phosphorylation of AKT (p-AKT), and this can be reversed with glycine treatment. We also found that administration of glycine can reduce neuronal cell death in SAH by activating the AKT pathway. Glycine was shown to upregulate miRNA-26b, which led to PTEN downregulation followed by AKT activation, resulting in inhibition of neuronal death. Inhibition of miRNA-26b, PTEN or AKT activation suppressed the neuroprotective effects of glycine. Glycine treatment also suppressed SAH-induced M1 microglial polarization and thereby inflammation. Taken together, we conclude that glycine has neuroprotective effects in SAH and is mediated by the miRNA-26b/PTEN/AKT signaling pathway, which may be a therapeutic target for treatment of SAH injury.


Assuntos
Glicina/farmacologia , MicroRNAs/fisiologia , Fármacos Neuroprotetores/farmacologia , PTEN Fosfo-Hidrolase/fisiologia , Transdução de Sinais/fisiologia , Hemorragia Subaracnóidea/fisiopatologia , Animais , Encéfalo/patologia , Linhagem Celular Tumoral , Humanos , Masculino , Ratos Sprague-Dawley , Hemorragia Subaracnóidea/patologia
7.
J Neural Transm (Vienna) ; 126(12): 1589-1597, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31707461

RESUMO

Microglia are the resident mononuclear immune cells of the central nervous system (CNS) and the activation of microglia contributes to the production of excessive neurotoxic factors. In particular, the overproduction of neurotoxic factors has critical effects on the development of brain injuries and neurodegenerative diseases. The human bone marrow-derived mesenchymal stem cells (hBM-MSCs) have blossomed into an effective approach with great potential for the treatment of neurodegenerative diseases and gliomas. The present study aimed to investigate the mechanism behind the therapeutic effect of hBM-MSCs on the activation of microglia in vitro. Specifically, the hBM-MSCs significantly inhibited the proliferation of lipopolysaccharide-activated microglial cells (LPS)-activated microglial cells. Additionally, we investigated whether the adenosine-monophosphate-activated protein kinase signaling (AMPK) pathway was involved in this process. Our data demonstrated that hBM-MSCs significantly increased the phosphorylated AMPK in LPS-activated microglial cells. In addition, our study indicated the inhibitory effect of hBM-MSCs on the pro-inflammatory mediators and oxidative stress by the AMPK pathway in LPS-activated microglial cells. These results could shed light on the understanding of the molecular basis for the inhibition of hBM-MSCs on LPS-activated microglial cells and provide a molecular mechanism for the hBM-MSCs implication in brain injuries and neurodegenerative diseases.


Assuntos
Adenilato Quinase/metabolismo , Células-Tronco Mesenquimais , Microglia , Animais , Células Cultivadas , Inflamação/induzido quimicamente , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Estresse Oxidativo/fisiologia , Ratos , Ratos Sprague-Dawley
8.
Biochem Biophys Res Commun ; 501(1): 85-91, 2018 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-29698679

RESUMO

Glycine has been shown to protect against ischemic stroke through various mechanisms. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) which antagonize Akt-dependent cell survival has been linked to neuronal damage. However, whether glycine has a neuroprotective property in intracerebral hemorrhage (ICH) was unknown. This study aimed to determine the protective effect of glycine in rats ICH. Adult male Sprague-Dawley (SD) rats were subjected to left striatum infusion of autologous blood. ICH animals received glycine (0.2-3 mg/kg, icv) at 1 h after ICH with or without pre-injection of Akt Inhibitor IV (100 µM, 2 µl, icv) 0.5 h prior to glycine treatment. Our results showed that in the perihematomal area PTEN was up-regulated in the early stage after ICH. However, glycine treatment decreased PTEN protein level and increased the phosphorylation level of AKT (p-AKT) in the perihematomal area. With the administration of glycine, neuronal death was significantly reduced and Evans blue leakage was alleviated as well as the brain edema after ICH. Moreover, hematoma volume was decreased and neurobehavioral outcome was improved. Nevertheless, Akt Inhibitor IV abolished the neuroprotective effects of glycine after ICH. Together, our findings demonstrate, for the first time, the protective role of glycine on ICH rats, and suggest that the neuroprotective effect of glycine was mediated through PTEN/Akt signal pathway.


Assuntos
Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/metabolismo , Glicina/farmacologia , Neuroproteção/efeitos dos fármacos , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Benzimidazóis/farmacologia , Benzotiazóis/farmacologia , Edema Encefálico/tratamento farmacológico , Edema Encefálico/metabolismo , Edema Encefálico/patologia , Morte Celular/efeitos dos fármacos , Hemorragia Cerebral/patologia , Modelos Animais de Doenças , Masculino , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , PTEN Fosfo-Hidrolase/antagonistas & inibidores , Fosforilação , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
9.
Neurochem Res ; 43(4): 775-784, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29460119

RESUMO

Curcumin, a phenolic pigment, plays an inhibitory role in astrocytes activation, a key step for neuropathic pain (NP). The present study aimed to investigate the mechanism behind the therapeutic effect of Curcumin on NP in vitro. Specifically, we investigated the inhibitory effect of Curcumin on tumor necrosis factor-α (TNF-α)-induced astrocyte migration. We also studied the effects of Curcumin on monocyte chemoattractant protein-1(MCP-1) expression and activity, as well as super oxide dismutase-2 (SOD2) expression and activity in TNF-α-induced astrocytes. Additionally, we investigated whether the adenosine-monophosphate-activated protein kinase signaling (AMPK) pathway was involved in this process. Our data demonstrated that Curcumin inhibited TNF-α-induced astrocytes migration, decreased MCP-1 expression, and up-regulated SOD2 expression in TNF-α-induced astrocytes in vitro. Our study also indicated that this process was mediated through the AMPK signaling pathway, as addition of Curcumin significantly increased the level of phosphorylated AMPK protein. Furthermore, the specific AMPK activator AICAR (5-aminoimidazole-4-carboxamide 1-D-ribofuranoside) mimicked the effects of Curcumin, whereas a selective AMPK inhibitor Compound C (also called dorsomorphin) partially blocked its function. These results could shed light on understanding of the molecular basis for the inhibition of Curcumin on MCP-1 expression during the process of astrocyte activation, and provide a molecular mechanism for using Curcumin in neuropathic pain.


Assuntos
Astrócitos/efeitos dos fármacos , Quimiocina CCL2/antagonistas & inibidores , Quimiocina CCL2/biossíntese , Curcumina/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fator de Necrose Tumoral alfa/toxicidade , Animais , Animais Recém-Nascidos , Antioxidantes/farmacologia , Astrócitos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Expressão Gênica , Sistema de Sinalização das MAP Quinases/fisiologia , Ratos , Ratos Sprague-Dawley
10.
Neurochem Res ; 43(7): 1424-1438, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29882124

RESUMO

Bisperoxovanadium (pyridine-2-carboxyl) [bpV(pic)] is a commercially available PTEN inhibitor. Previous studies from us and others have shown that bpV(pic) confers neuroprotection in cerebral ischemia injury. We set up to determine whether ERK 1/2 activation plays a role in bpV(pic)-induced neuroprotective effect in cerebral ischemia injury. We found that the phosphorylation levels of Akt (p-AKT) and ERK1/2 (p-ERK 1/2) were down-regulated after cerebral ischemia-reperfusion injury. The injection of bpV(pic) after injury not only increased the level of p-AKT but also the level of p-ERK 1/2. While the inhibition of PTEN mediated the up-regulatation of p-AKT and p-ERK 1/2 by bpV(pic). Interestingly, the ERK 1/2 activation induced by bpV(pic) was also independent of the inhibition of PTEN. Our results indicate that bpV(pic) protects against OGD-induced neuronal death and promotes the functional recovery of stroke animals through PTEN inhibition and ERK 1/2 activation, respectively. This study suggests that the effect of bpV(pic) on ERK 1/2 signaling should be considered while using bpV(pic) as a PTEN inhibitor.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Compostos de Vanádio/farmacologia , Animais , Modelos Animais de Doenças , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos
11.
Cyborg Bionic Syst ; 5: 0062, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38188984

RESUMO

Tumors significantly impact individuals' physical well-being and quality of life. With the ongoing advancements in optical technology, information technology, robotic technology, etc., laser technology is being increasingly utilized in the field of tumor treatment, and laser ablation (LA) of tumors remains a prominent area of research interest. This paper presents an overview of the recent progress in tumor LA therapy, with a focus on the mechanisms and biological effects of LA, commonly used ablation lasers, image-guided LA, and robotic-assisted LA. Further insights and future prospects are discussed in relation to these aspects, and the paper proposed potential future directions for the development of tumor LA techniques.

12.
bioRxiv ; 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36711707

RESUMO

Cristae membrane state plays a central role in regulating mitochondrial function and cellular metabolism. The protein Optic atrophy 1 (Opa1) is an important crista remodeler that exists as two forms in the mitochondrion, a membrane-anchored long form (l-Opa1) and a processed short form (s-Opa1). The mechanisms for how Opa1 influences cristae shape have remained unclear due to lack of native three-dimensional views of cristae. We perform in situ cryo-electron tomography of cryo-focused ion beam milled mouse embryonic fibroblasts with defined Opa1 states to understand how each form of Opa1 influences cristae architecture. In our tomograms, we observe a variety of cristae shapes with distinct trends dependent on s-Opa1:l-Opa1 balance. Increased l-Opa1 levels promote cristae stacking and elongated mitochondria while increased s-Opa1 levels correlated with irregular cristae packing and round mitochondria shape. Functional assays indicate a role for l-Opa1 in wild-type apoptotic and calcium handling responses, and compromised respiratory function under Opa1 imbalance. In summary, we provide three-dimensional visualization of cristae architecture to reveal relationships between mitochondrial ultrastructure and cellular function dependent on Opa1-mediated membrane remodeling.

13.
Cancer Res ; 83(20): 3442-3461, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37470810

RESUMO

Although external beam radiotherapy (xRT) is commonly used to treat central nervous system (CNS) tumors in patients of all ages, young children treated with xRT frequently experience life-altering and dose-limiting neurocognitive impairment (NI) while adults do not. The lack of understanding of mechanisms responsible for these differences has impeded the development of neuroprotective treatments. Using a newly developed mouse model of xRT-induced NI, we found that neurocognitive function is impaired by ionizing radiation in a dose- and age-dependent manner, with the youngest animals being most affected. Histologic analysis revealed xRT-driven neuronal degeneration and cell death in neurogenic brain regions in young animals but not adults. BH3 profiling showed that neural stem and progenitor cells, neurons, and astrocytes in young mice are highly primed for apoptosis, rendering them hypersensitive to genotoxic damage. Analysis of single-cell RNA sequencing data revealed that neural cell vulnerability stems from heightened expression of proapoptotic genes including BAX, which is associated with developmental and mitogenic signaling by MYC. xRT induced apoptosis in primed neural cells by triggering a p53- and PUMA-initiated, proapoptotic feedback loop requiring cleavage of BID and culminating in BAX oligomerization and caspase activation. Notably, loss of BAX protected against apoptosis induced by proapoptotic signaling in vitro and prevented xRT-induced apoptosis in neural cells in vivo as well as neurocognitive sequelae. On the basis of these findings, preventing xRT-induced apoptosis specifically in immature neural cells by blocking BAX, BIM, or BID via direct or upstream mechanisms is expected to ameliorate NI in pediatric patients with CNS tumor. SIGNIFICANCE: Age- and differentiation-dependent apoptotic priming plays a pivotal role in driving radiotherapy-induced neurocognitive impairment and can be targeted for neuroprotection in pediatric patients.


Assuntos
Proteínas Reguladoras de Apoptose , Apoptose , Animais , Criança , Pré-Escolar , Humanos , Camundongos , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose/metabolismo , Proteína X Associada a bcl-2/metabolismo , Morte Celular , Transdução de Sinais , Proteína Supressora de Tumor p53/genética
14.
Theranostics ; 13(14): 4711-4729, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37771768

RESUMO

Background: The introduction of magnetic resonance (MR)-guided radiation treatment planning has opened a new space for theranostic nanoparticles to reduce acute toxicity while improving local control. In this work, second-generation AGuIX® nanoparticles (AGuIX-Bi) are synthesized and validated. AGuIX-Bi are shown to maintain MR positive contrast while further amplifying the radiation dose by the replacement of some Gd3+ cations with higher Z Bi3+. These next-generation nanoparticles are based on the AGuIX® platform, which is currently being evaluated in multiple Phase II clinical trials in combination with radiotherapy. Methods: In this clinically scalable methodology, AGuIX® is used as an initial chelation platform to exchange Gd3+ for Bi3+. AGuIX-Bi nanoparticles are synthesized with three ratios of Gd/Bi, each maintaining MR contrast while further amplifying radiation dose relative to Bi3+. Safety, efficacy, and theranostic potential of the nanoparticles were evaluated in vitro and in vivo in a human non-small cell lung cancer model. Results: We demonstrated that increasing Bi3+ in the nanoparticles is associated with more DNA damage and improves in vivo efficacy with a statistically significant delay in tumor growth and 33% complete regression for the largest Bi/Gd ratio tested. The addition of Bi3+ by our synthetic method leads to nanoparticles that present slightly altered pharmacokinetics and lengthening of the period of high tumor accumulation with no observed evidence of toxicity. Conclusions: We confirmed the safety and enhanced efficacy of AGuIX-Bi with radiation therapy at the selected ratio of 30Gd/70Bi. These results provide crucial evidence towards patient translation.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Nanopartículas , Humanos , Medicina de Precisão , Meios de Contraste , Imageamento por Ressonância Magnética/métodos , Doses de Radiação , Nanomedicina Teranóstica/métodos
15.
J Gastroenterol Hepatol ; 27(8): 1395-404, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22497484

RESUMO

BACKGROUND AND AIM: Aplasia ras homolog member I (ARHI) is a maternally imprinted tumor suppressor gene. ARHI protein is widely expressed in many types of human tissues; however, its expression is frequently reduced or absent in various tumors and plays a tumor suppressor role for in vitro study. In this study, we investigated the expression level of ARHI in gastric cancer in order to investigate the function of ARHI and signaling pathways that might be linked during gastric cancer development. METHODS: ARHI mRNA and protein expression levels were analyzed in primary gastric cancer tissues, adjacent noncancerous gastric tissues and gastric cancer cell lines using semi-quantitative polymerase chain reaction, western blotting and immunohistochemistry, respectively. RESULTS: Our results showed that both mRNA and protein expression levels of the ARHI gene were significantly downregulated (P < 0.05) in gastric cancer tissues and cell lines compared to the corresponding normal control groups. The protein expression level of ARHI was not associated with age, gender, location of tumor, tumor size or metastasis in patients with gastric cancer. However, a significant correlation between the level of ARHI protein expression and the degree of tumor differentiation and Tumor-Node-Metastasis stage was observed (P < 0.05). Furthermore, results of the methyl thiazolyl tetrazolium and Transwell assays and flow cytometric analysis showed increased cell proliferation, migration and anti-apoptotic capacities in the well-differentiated gastric cancer MKN-28 cell line, which has stably silenced ARHI protein expression. CONCLUSION: Our data indicate that ARHI expression is downregulated in human gastric cancer and it may be a novel tumor suppressive target for gastric cancer therapy.


Assuntos
Proliferação de Células , Inativação Gênica , Neoplasias Gástricas/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Apoptose , Western Blotting , Diferenciação Celular , Linhagem Celular Tumoral , Movimento Celular , Regulação para Baixo , Ativação Enzimática , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fosforilação , Interferência de RNA , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Transfecção , Proteínas rho de Ligação ao GTP/genética
16.
Sci Adv ; 8(45): eabn6579, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36351019

RESUMO

Although major organ toxicities frequently arise in patients treated with cytotoxic or targeted cancer therapies, the mechanisms that drive them are poorly understood. Here, we report that vascular endothelial cells (ECs) are more highly primed for apoptosis than parenchymal cells across many adult tissues. Consequently, ECs readily undergo apoptosis in response to many commonly used anticancer agents including cytotoxic and targeted drugs and are more sensitive to ionizing radiation and BH3 mimetics than parenchymal cells in vivo. Further, using differentiated isogenic human induced pluripotent stem cell models of ECs and vascular smooth muscle cells (VSMCs), we find that these vascular cells exhibit distinct drug toxicity patterns, which are linked to divergent therapy-induced vascular toxicities in patients. Collectively, our results demonstrate that vascular cells are highly sensitive to apoptosis-inducing stress across life span and may represent a "weakest link" vulnerability in multiple tissues for development of toxicities.


Assuntos
Células-Tronco Pluripotentes Induzidas , Neoplasias , Adulto , Humanos , Músculo Liso Vascular/fisiologia , Células Endoteliais , Longevidade , Células-Tronco Pluripotentes Induzidas/fisiologia , Células Cultivadas , Neoplasias/etiologia
17.
iScience ; 25(10): 105064, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36147946

RESUMO

Poration of the outer mitochondrial membrane by the effector BCL-2 proteins BAK and BAX initiates apoptosis. BH3-only initiators BID and BIM trigger conformational changes in BAK and BAX transforming them from globular dormant proteins to oligomers of the apoptotic pores. Small molecules that can directly activate effectors are being sought for applications in cancer treatment. Here, we describe the small molecule SJ572946, discovered in a fragment-based screen that binds to the activation groove of BAK and selectively triggers BAK activation over that of BAX in liposome and mitochondrial permeabilization assays. SJ572946 independently kills BAK-expressing BCL2allKO HCT116 cells revealing on target cellular activity. In combination with apoptotic inducers and BH3 mimetics, SJ572946 kills experimental cancer cell lines. SJ572946 also cooperates with the endogenous BAK activator BID in activating a misfolded BAK mutant substantially impaired in activation. SJ572946 is a proof-of-concept tool for probing BAK-mediated apoptosis in preclinical cancer research.

18.
Nat Commun ; 13(1): 5789, 2022 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-36184661

RESUMO

Immunoglobulin light chain (AL) amyloidosis is an incurable hematologic disorder typically characterized by the production of amyloidogenic light chains by clonal plasma cells. These light chains misfold and aggregate in healthy tissues as amyloid fibrils, leading to life-threatening multi-organ dysfunction. Here we show that the clonal plasma cells in AL amyloidosis are highly primed to undergo apoptosis and dependent on pro-survival proteins MCL-1 and BCL-2. Notably, this MCL-1 dependency is indirectly targeted by the proteasome inhibitor bortezomib, currently the standard of care for this disease and the related plasma cell disorder multiple myeloma, due to upregulation of pro-apoptotic Noxa and its inhibitory binding to MCL-1. BCL-2 inhibitors sensitize clonal plasma cells to multiple front-line therapies including bortezomib, dexamethasone and lenalidomide. Strikingly, in mice bearing AL amyloidosis cell line xenografts, single agent treatment with the BCL-2 inhibitor ABT-199 (venetoclax) produces deeper remissions than bortezomib and triples median survival. Mass spectrometry-based proteomic analysis reveals rewiring of signaling pathways regulating apoptosis, proliferation and mitochondrial metabolism between isogenic AL amyloidosis and multiple myeloma cells that divergently alter their sensitivity to therapies. These findings provide a roadmap for the use of BH3 mimetics to exploit endogenous and induced apoptotic vulnerabilities in AL amyloidosis.


Assuntos
Antineoplásicos , Amiloidose de Cadeia Leve de Imunoglobulina , Mieloma Múltiplo , Amiloide/uso terapêutico , Animais , Antineoplásicos/farmacologia , Bortezomib/farmacologia , Bortezomib/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Humanos , Cadeias Leves de Imunoglobulina , Amiloidose de Cadeia Leve de Imunoglobulina/tratamento farmacológico , Lenalidomida/farmacologia , Lenalidomida/uso terapêutico , Camundongos , Mieloma Múltiplo/tratamento farmacológico , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Inibidores de Proteassoma , Proteômica , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sulfonamidas
19.
Asian Pac J Cancer Prev ; 22(1): 119-123, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33507688

RESUMO

OBJECTIVES: The association of angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and the development of type 2 diabetes mellitus (T2DM) has been debated vigorously but still remains controversial. Therefore, the current study was designed to determine the possible association between ACE I/D polymorphism and T2DM and hypertension (HTN) in a population of Saudi Arabian participants. METHODS: A total of 143 individuals were recruited for the study, consisting of 74 controls and 69 patients with T2DM. Genotyping was performed via polymerase chain reaction. RESULTS: The genotype frequencies for DD, ID and II in controls were 52.7%, 39.2% and 8.1%, whereas in T2D patients it was 52.2%, 40.6% and 7.2% respectively. The DD frequency was highest out of the three genotypes in both the controls and the T2DM patients. CONCLUSION: There was no significant difference found in the genotype and allele frequencies between cases and controls, suggesting that insertion/deletion polymorphism in the ACE gene may not be associated with an increased susceptibility to type 2 diabetes in our study population.


Assuntos
Biomarcadores/análise , Diabetes Mellitus Tipo 2/patologia , Mutação INDEL , Peptidil Dipeptidase A/genética , Polimorfismo Genético , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Arábia Saudita
20.
Tissue Eng Part C Methods ; 27(9): 497-511, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34445889

RESUMO

Skeletal muscle tissue engineering (SMTE) is of great significance in the study of skeletal muscle physiology and pathology, which could be used in skeletal muscle graft. The scientometric analysis of SMTE can help researchers to quickly understand the evolutive history, status, novelties, and trend of this field. In this study, we performed a scientometric study that can be used to construct and visualize networks of SMTE using VOSviewer. A total of 1384 documents published between 1994 and 2020 were retrieved and analyzed. Our results showed that number of publications in SMTE has increased slowly from 1994 to 2014 and has increased rapidly from 2015 to 2020. The geographical distribution of publications in terms of total publications about SMTE is concentrated in Europe and the United States. The most productive institution was University of Michigan, while Harvard University and the University of Pittsburgh were ranked the second and third places. SMTE influenced a wide spectrum of disciplines, including Biology and Medicine and Physical Sciences. In addition, the research hotspot of SMTE was expanding from seed cells to the combination with advanced strategies (electrostatic spinning, bioprinting, and materials) for emulating the highly bionic engineered skeletal muscle tissues. This study provided a unique perspective for understanding the history and trends of SMTE, which could help to promote the rapid development of the field. Impact statement Skeletal muscle tissue engineering (SMTE), which acts as an important branch of tissue engineering, hold a great promise in the study of skeletal muscle physiology and pathology. The field of SMTE has developed rapidly in recent decades while still lacking studies based on scientometric methods. This article provided the first scientometric study of SMTE from development trends and evolution of the field. The results indicated that the field of SMTE was experiencing rapid growth and had a significant impact on multiple fields, particularly in Biology and Medicine and Physical Sciences.


Assuntos
Bioimpressão , Engenharia Tecidual , Humanos , Músculo Esquelético
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