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1.
Int J Mol Sci ; 23(15)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35897675

RESUMO

Approximately 75% of diagnosed breast cancer tumors are estrogen-receptor-positive tumors and are associated with a better prognosis due to response to hormonal therapies. However, around 40% of patients relapse after hormonal therapies. Genomic analysis of gene expression profiles in primary breast cancers and tamoxifen-resistant cell lines suggested the potential role of miR-489 in the regulation of estrogen signaling and development of tamoxifen resistance. Our in vitro analysis showed that loss of miR-489 expression promoted tamoxifen resistance, while overexpression of miR-489 in tamoxifen-resistant cells restored tamoxifen sensitivity. Mechanistically, we found that miR-489 is an estrogen-regulated miRNA that negatively regulates estrogen receptor signaling by using at least the following two mechanisms: (i) modulation of the ER phosphorylation status by inhibiting MAPK and AKT kinase activities; (ii) regulation of nuclear-to-cytosol translocation of estrogen receptor α (ERα) by decreasing p38 expression and consequently ER phosphorylation. In addition, miR-489 can break the positive feed-forward loop between the estrogen-Erα axis and p38 MAPK in breast cancer cells, which is necessary for its function as a transcription factor. Overall, our study unveiled the underlying molecular mechanism by which miR-489 regulates an estrogen signaling pathway through a negative feedback loop and uncovered its role in both the development of and overcoming of tamoxifen resistance in breast cancers.


Assuntos
Neoplasias da Mama , MicroRNAs , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Receptor alfa de Estrogênio/metabolismo , Estrogênios/farmacologia , Retroalimentação , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/metabolismo , Recidiva Local de Neoplasia/genética , Transdução de Sinais , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
2.
Adv Funct Mater ; 31(30)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34421476

RESUMO

Recently discovered "Trim-Away" mechanism opens a new window for fast and selective degradation of endogenous proteins. However, the in vivo and clinical application of this approach is stuck by the requirement of special skills and equipment needed for the intracellular delivery of antibodies. Hereby, an antibody conjugated polymer nanogel system, Nano-ERASER, for intracellular delivery and release of antibody, and degradation of a specific endogenous protein has been developed. After being delivered into cells, the antibody is released and forms complex with its target protein, and subsequently binds to the Fc receptor of TRIM21. The resulted complex of target protein/antibody/TRIM21 is then degraded by the proteasome. The efficacy of Nano-ERASER has been validated by depleting GFP protein in a GFP expressing cell line. Furthermore, Nano-ERASER successfully degrades COPZ1, a vital protein for cancer cells, and kills those cells while sparing normal cells. Benefit from its convenience and targeted delivery merit, Nano-ERASER technique is promising in providing a reliable tool for endogenous protein function study as well as paves the way for novel antibody-based Trim-Away therapeutic modalities for cancer and other diseases.

3.
Biochem Biophys Res Commun ; 526(3): 592-598, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32247607

RESUMO

Extracellular acidification, playing a promoting role in the process of acute pancreatitis, has been reported to activate Cl- channels in several types of cells. However, whether extracellular acidification aggravates acute pancreatitis via activating Cl- channels remains unclear. Here, we investigated the effects of extracellular acidification on Cl- channels in rat pancreatic acinar AR42J cells using whole-cell patch-clamp recordings. We found that extracellular acidification induced a moderately outward-rectified Cl- current, with a selectivity sequence of I- > Br- ≥ Cl- > gluconate-, while intracellular acidification failed to induce the currents. The acid-sensitive currents were inhibited by Cl- channel blockers, 4,4'-Diisothiocyanatostilbene-2,2'-disulfonic acid disodium salt hydrate and 5-Nitro-2-(3-phenylpropylamino) benzoic acid. After ClC-3 was silenced by ClC-3 shRNA, the acid-sensitive Cl- currents were attenuated significantly, indicating that ClC-3 plays a vital role in the induction of acid-sensitive Cl- currents. Extracellular acid elevated the intracellular level of reactive oxygen species (ROS) significantly, prior to inducing Cl- currents. When ROS production was scavenged, the acid-sensitive Cl- currents were abolished. Whereas, the level of acid-induced ROS was unaffected with silence of ClC-3. Our findings above demonstrate that extracellular acidification induces a Cl- current in pancreatic acinar cells via promoting ROS generation, implying an underlying mechanism that extracellular acidification might aggravate acute pancreatitis through Cl- channels.


Assuntos
Células Acinares/metabolismo , Canais de Cloreto/metabolismo , Pâncreas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células Acinares/citologia , Animais , Linhagem Celular , Cloretos/metabolismo , Espaço Extracelular/metabolismo , Concentração de Íons de Hidrogênio , Pâncreas/citologia , Técnicas de Patch-Clamp , Ratos
4.
Small ; 16(38): e2003398, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32797711

RESUMO

Photothermal therapy (PTT) has attracted tremendous attention due to its noninvasiveness and localized treatment advantages. However, heat shock proteins (HSPs) associated self-preservation mechanisms bestow cancer cells thermoresistance to protect them from the damage of PTT. To minimize the thermoresistance of cancer cells and improve the efficacy of PTT, an integrated on-demand nanoplatform composed of a photothermal conversion core (gold nanorod, GNR), a cargo of a HSPs inhibitor (triptolide, TPL), a mesoporous silica based nanoreservoir, and a photothermal and redox di-responsive polymer shell is developed. The nanoplatform can be enriched in the tumor site, and internalized into cancer cells, releasing the encapsulated TPL under the trigger of intracellular elevated glutathione and near-infrared laser irradiation. Ultimately, the liberated TPL could diminish thermoresistance of cancer cells by antagonizing the PTT induced heat shock response via multiple mechanisms to maximize the PTT effect for cancer treatment.


Assuntos
Ouro , Terapia Fototérmica , Diterpenos , Compostos de Epóxi , Oxirredução , Fenantrenos , Fototerapia , Temperatura
5.
Biochem J ; 476(9): 1323-1333, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30992317

RESUMO

Nutrient deficiency develops frequently in nasopharyngeal carcinoma cell (CNE-2Z) due to the characteristics of aggregation and uncontrolled proliferation. Therefore, starvation can induce autophagy in these cells. Chloride channel 3 (ClC-3), a member of the chloride channel family, is involved in various biological processes. However, whether ClC-3 plays an important role in starvation-induced autophagy is unclear. In this study, Earle's balanced salt solution (EBSS) was used to induce autophagy in CNE-2Z cells. We found that autophagy and the chloride current induced by EBSS were inhibited by chloride channel blockers. ClC-3 knockdown inhibited the degradation of LC3-II and P62. Furthermore, when reactive oxygen species (ROS) generation was suppressed by antioxidant N-acetyl-l-cysteine (L-NAC) pretreatment, EBSS-induced autophagy was inhibited, and the chloride current was unable to be activated. Nevertheless, ClC-3 knockdown had little effect on ROS levels, indicating that ROS acted upstream of ClC-3 and that both ROS and ClC-3 participated in EBSS-induced autophagy regulation in CNE-2Z.


Assuntos
Morte Celular Autofágica , Canais de Cloreto/metabolismo , Regulação Neoplásica da Expressão Gênica , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Proteínas de Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima , Acetilcisteína/farmacologia , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Transporte de Íons/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologia , Proteínas de Ligação a RNA/metabolismo
6.
Adv Funct Mater ; 29(50)2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-33041742

RESUMO

Clinical application of drug cocktails for cancer therapy is limited by their severe systemic toxicity. To solve a catch-22 dilemma between safety and efficacy for drug cocktails, a hetero-targeted nano-cocktail (PPPDMA) with traceless linkers has been developed. In the PPPDMA nanogel, a hetero-targeting strategy is employed to improve its tumor selective targeting efficacy by overcoming the cancer cell mono-ligand density limitation. Benefit from its glutathione and reactive oxygen species responsiveness, the loaded paclitaxel and doxorubicin can be quickly and tracelessly released into the cytoplasm in their original form, which bestows PPPDMA nanogels the capability to overwhelm the processing capacity of cancer cell's P-glycoprotein efflux pump allows, and ultimately kill them without inducing side effects. The PPPDMA treatment reduced its tumor burden over 99% (in tumor weight) and 96% (in tumor number). Most importantly, no detectable tumor in more than half of the PPPDMA treated mice. We conclude that traceless linker and hetero-targeted nano-cocktail strategy could be a safe and effective approach for cancer treatment.

7.
Mol Pharm ; 14(5): 1591-1600, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28335600

RESUMO

One hallmark of neuroinflammation is the activation of microglia, which triggers the production and release of reactive oxygen species (ROS), nitrate, nitrite, and cytokines. N-Acetyl cysteine (NAC) is a free radical scavenger that is involved in the intracellular and extracellular detoxification of reactive oxygen species in the brain. However, the clinical application of NAC is limited by its low bioavailability and short half-life. Herein, NAC was conjugated to a polymer through a disulfide bond to form a NAC-prodrug nanoparticle (NAC-NP). Dynamic light scattering found that the NAC-NP has a size of around 50 nm. In vitro studies revealed that the release of NAC from NAC-NP is responsive to its environmental redox potential. For mimicking neuroinflammation in vitro, microglial cells were stimulated by a lipopolysaccharide (LPS), and the effect of NAC-NP on activated microglia was investigated. The study found that the morphology as well as the expression of microgliosis marker Iba-1 of the cells treated with NAC-NPs and LPS were close to those of control cells, indicating that NAC-NPs can inhibit the activation of microglia stimulated by LPS. Compared with free NAC, the production of ROS, NO3-, NO2-, tumor necrosis factor-α (TNF-α), and interleukin (IL)-1ß from the LPS-stimulated microglia was considerably decreased when the cells were pretreated with NAC-NPs. Furthermore, LPS-induced microglial phagocytocis of neurons was inhibited in the presence of NAC-NPs. These results indicated that NAC-NPs are more effective than free NAC for reversing the effect of LPS on microglia and subsequently protecting neurons.


Assuntos
Acetilcisteína/química , Microglia/citologia , Microglia/efeitos dos fármacos , Nanopartículas/química , Neurônios/citologia , Neurônios/efeitos dos fármacos , Pró-Fármacos/química , Animais , Antioxidantes/metabolismo , Linhagem Celular , Imuno-Histoquímica , Interleucina-1beta/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Microglia/metabolismo , Neurônios/metabolismo , Oxirredução/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
8.
Mol Pharm ; 11(6): 1897-905, 2014 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-24779647

RESUMO

Ideal "smart" nanoparticles for drug delivery should enhance therapeutic efficacy without introducing side effects. To achieve that, we developed a drug delivery system (HCN) based on a polymer-drug conjugate of poly[2-(pyridin-2-yldisulfanyl)]-graft-poly(ethylene glycol) and camptothecin with an intracellularly cleavable linker and human epidermal growth factor receptor 2 (HER2) targeting ligands. An in vitro drug release study found that HCN was stable in the physiological environment and supersensitive to the stimulus of elevated intracellular redox potential, releasing all payloads in less than 30 min. Furthermore, confocal microscopy revealed that HCN could specifically enter HER2-positive cancer cells. As a consequence, HCN could effectively kill HER2-positive cancer cells while not affecting HER2-negative cells.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Camptotecina/administração & dosagem , Camptotecina/química , Nanopartículas/administração & dosagem , Nanopartículas/química , Receptor ErbB-2/genética , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Feminino , Células HCT116 , Humanos , Células KB , Oxirredução , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Polímeros/administração & dosagem , Polímeros/química
9.
Exp Neurol ; 378: 114821, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38782349

RESUMO

Neonatal hypoxia-ischemia (HI) results in behavioral deficits, characterized by neuronal injury and retarded myelin formation. To date, limited treatment methods are available to prevent or alleviate neurologic sequelae of HI. Intermittent theta-burst stimulation (iTBS), a non-invasive therapeutic procedure, is considered a promising therapeutic tool for treating some neurocognitive disorders and neuropsychiatric diseases. Hence, this study aims to investigate whether iTBS can prevent the negative behavioral manifestations of HI and explore the mechanisms for associations. We exposed postnatal day 10 Sprague-Dawley male and female rats to 2 h of hypoxia (6% O2) following right common carotid artery ligation, resulting in oligodendrocyte (OL) dysfunction, including reduced proliferation and differentiation of oligodendrocyte precursor cells (OPCs), decreased OL survival, and compromised myelin in the corpus callosum (CC) and hippocampal dentate gyrus (DG). These alterations were concomitant with cognitive dysfunction and depression-like behaviors. Crucially, early iTBS treatment (15 G, 190 s, seven days, initiated one day post-HI) significantly alleviated HI-caused myelin damage and mitigated the neurologic sequelae both in male and female rats. However, the late iTBS treatment (initiated 18 days after HI insult) could not significantly impact these behavioral deficits. In summary, our findings support that early iTBS treatment may be a promising strategy to improve HI-induced neurologic disability. The underlying mechanisms of iTBS treatment are associated with promoting the differentiation of OPCs and alleviating myelin damage.


Assuntos
Animais Recém-Nascidos , Hipóxia-Isquemia Encefálica , Bainha de Mielina , Ratos Sprague-Dawley , Animais , Masculino , Feminino , Ratos , Hipóxia-Isquemia Encefálica/terapia , Hipóxia-Isquemia Encefálica/patologia , Bainha de Mielina/patologia , Bainha de Mielina/metabolismo , Estimulação Magnética Transcraniana/métodos , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Células Precursoras de Oligodendrócitos
10.
bioRxiv ; 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38746389

RESUMO

Tumor-associated macrophages exhibit high heterogeneity and contribute to the establishment of an immunosuppressive tumor microenvironment (TME). Although numerous studies have demonstrated that extracellular factors promote macrophage proliferation and polarization, the regulatory mechanisms governing the differentiation process to generate phenotypically, and functionally diverse macrophage subpopulations remain largely unexplored. In this study, we examined the influence of interleukin 1α (IL-1α) on the development of an immunosuppressive TME using orthotopic transplantation murine models of breast cancer. Deletion of host Il1α led to the rejection of inoculated congenic tumors. Single-cell sequencing analysis revealed that CX3CR1+ macrophage cells were the primary sources of IL-1α in the TME. The absence of IL-1α reprogrammed the monocyte-to-macrophage differentiation process within the TME, characterized by a notable decrease in the subset of CX3CR+ ductal-like macrophages and an increase in iNOS-expressing inflammatory cells. Comparative analysis of gene signatures in both human and mouse macrophage subsets suggested that IL-1α deficiency shifted the macrophage polarization from M2 to M1 phenotypes, leading to enhanced cytotoxic T lymphocyte activity in the TME. Importantly, elevated levels of IL-1α in human cancers were associated with worse prognosis following immunotherapy. These findings underscore the pivotal role of IL-1α in shaping an immune-suppressive TME through the regulation of macrophage differentiation and activity, highlighting IL-1α as a potential target for breast cancer treatment.

11.
Biomater Sci ; 11(16): 5641-5652, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37409576

RESUMO

Our previous research discovered that combining the PDA-PEG polymer with copper ions can selectively kill cancer cells. However, the precise mechanism by which this combination functions was not fully understood. This study revealed that the PDA-PEG polymer and copper ions form complementary PDA-PEG/copper (Poly/Cu) nanocomplexes by facilitating copper ion uptake and lysosomal escape. An in vitro study found that Poly/Cu killed 4T1 cells through a lysosome cell death pathway. Furthermore, Poly/Cu inhibited both the proteasome function and autophagy pathway and induced immunogenic cell death (ICD) in 4T1 cells. The Poly/Cu induced ICD coupled with the checkpoint blockade effect of the anti-PD-L1 antibody (aPD-L1) synergistically promoted immune cell penetration into the tumor mass. Benefiting from the tumor-targeting effect and cancer cell-selective killing effect of Poly/Cu complexes, the combinatory treatment of aPD-L1 and Poly/Cu effectively suppressed the progression of triple-negative breast cancer without inducing systemic side effects.


Assuntos
Polímeros , Neoplasias de Mama Triplo Negativas , Humanos , Polímeros/uso terapêutico , Cobre/farmacologia , Cobre/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Imunoterapia , Lisossomos , Morte Celular , Linfócitos , Linhagem Celular Tumoral
12.
Res Sq ; 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36711780

RESUMO

Trim-Away is a versatile intracellular protein degradation pathway that has been extensively explored in vitro. However, the in vivo application of Trim-Away is limited at oocyte and zygote stages due to the lack of an in vivo practical approach for intracellular antibody delivery. To broaden the application of Trim-Away, especially for clinical use, we developed a nanogel-based Nano-ERASER system. Here, we demonstrated that the intracellular delivery of anti-programmed cell death ligand 1 (PD-L1) antibody through Nano-ERASER could effectively deplete PD-L1 in triple negative breast cancer (TNBC) cells and induce cancer cell death. Furthermore, with the help of a tumor tissue-targeted nanogel, anti-PD-L1 antibody-loaded Nano-ERASER effectively inhibited tumor progression in a TNBC mouse model. These results confirmed that Nano-ERASER realized Trim-Away in adult animals for the first time, which could be an effective tool for disease treatment and studying gene/protein function both in vitro and in vivo.

13.
Mol Pharm ; 9(9): 2719-29, 2012 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-22876763

RESUMO

To mimic the clinic dosing pattern, initially administering high loading dose and then low maintenance dose, we designed a novel poly(2-(pyridin-2-yldisulfanyl)ethyl acrylate) (PDS) based nanoparticle delivery system. Side chain functional PDS was synthesized by free radical polymerization. Polyethylene glycol and cyclo(Arg-Gly-Asp-d-Phe-Cys) (cRGD) peptide was conjugated to PDS through thiol-disulfide exchange reaction to achieve RPDSG polymer. RPDSG/DOX, RPDSG nanoparticle loaded with doxorubicin, was fabricated by cosolvent dialysis method. The size of the nanoparticles was 50.13 ± 0.5 nm in PBS. The RPDSG/DOX nanoparticle is stable in physiological condition while quickly releasing doxorubicin with the trigger of acidic pH and redox potential. Furthermore, it shows a two-phase release kinetics, providing both loading dose and maintenance dose for cancer therapy. The conjugation of RGD peptide enhanced the cellular uptake and nuclear localization of the RPDSG/DOX nanoparticles. RPDSG/DOX exhibits IC(50) close to that of free doxorubicin for HCT-116 colon cancer cells. Due to the synergetic effect of RGD targeting effect and its two-phase release kinetics, RPDSG/DOX nanoparticles display significantly higher anticancer efficacy than that of free DOX at concentrations higher than 5 µM. These results suggest that RPDSG/DOX could be a promising nanotherapeutic for tumor-targeted chemotherapy.


Assuntos
Doxorrubicina/química , Nanopartículas/administração & dosagem , Nanopartículas/química , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Células HCT116 , Humanos , Concentração de Íons de Hidrogênio , Cinética , Oligopeptídeos/administração & dosagem , Oligopeptídeos/química , Oxirredução , Tamanho da Partícula , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Polímeros/administração & dosagem , Polímeros/química
14.
Adv Drug Deliv Rev ; 191: 114619, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36372301

RESUMO

Despite its prevalence in the management of peripheral tumors, compared to surgery and radiation therapy, chemotherapy is still a suboptimal intervention in fighting against brain cancer and cancer brain metastases. This discrepancy is mainly derived from the complicatedly physiological characteristic of intracranial tumors, including the presence of blood-brain barrier (BBB) and limited enhanced permeability and retention (EPR) effect attributed to blood-brain tumor barrier (BBTB), which largely lead to insufficient therapeutics penetrating to tumor lesions to produce pharmacological effects. Therefore, dependable methodologies that can boost the efficacy of chemotherapy for brain tumors are urgently needed. Recently, nanomedicines have shown great therapeutic potential in brain tumors by employing various transcellular strategies, paracellular strategies, and their hybrids, such as adsorptive-mediated transcytosis, receptor-mediated transcytosis, BBB disruption technology, and so on. It is compulsory to comprehensively summarize these practices to shed light on future directions in developing therapeutic regimens for brain tumors. In this review, the biological and pathological characteristics of brain tumors, including BBB and BBTB, are illustrated. After that, the emerging delivery strategies for brain tumor management are summarized into different classifications and supported with detailed examples. Finally, the potential challenges and prospects for developing and clinical application of brain tumor-oriented nanomedicine are discussed.


Assuntos
Neoplasias Encefálicas , Nanopartículas , Humanos , Barreira Hematoencefálica , Neoplasias Encefálicas/tratamento farmacológico , Transcitose , Nanomedicina , Sistemas de Liberação de Medicamentos/métodos
15.
Nanomicro Lett ; 14(1): 114, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35482117

RESUMO

Early-stage brain metastasis of breast cancer (BMBC), due to the existence of an intact blood-brain barrier (BBB), is one of the deadliest neurologic complications. To improve the efficacy of chemotherapy for BMBC, a Trojan horse strategy-based nanocarrier has been developed by integrating the cell membrane of a brain-homing cancer cell and a polymeric drug depot. With the camouflage of a MDA-MB-231/Br cell membrane, doxorubicin-loaded poly (D, L-lactic-co-glycolic acid) nanoparticle (DOX-PLGA@CM) shows enhanced cellular uptake and boosted killing potency for MDA-MB-231/Br cells. Furthermore, DOX-PLGA@CM is equipped with naturally selected molecules for BBB penetration, as evidenced by its boosted capacity in entering the brain of both healthy and early-stage BMBC mouse models. Consequently, DOX-PLGA@CM effectively reaches the metastatic tumor lesions in the brain, slows down cancer progression, reduces tumor burden, and extends the survival time for the BMBC animal. Furthermore, the simplicity and easy scale-up of the design opens a new window for the treatment of BMBC and other brain metastatic cancers.

16.
Anal Chem ; 83(22): 8816-20, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21967571

RESUMO

The manipulation of cells inside water-in-oil droplets is essential for high-throughput screening of cell-based assays using droplet microfluidics. Cell transfection inside droplets is a critical step involved in functional genomics studies that examine in situ functions of genes using the droplet platform. Conventional water-in-hydrocarbon oil droplets are not compatible with chemical transfection due to its damage to cell viability and extraction of organic transfection reagents from the aqueous phase. In this work, we studied chemical transfection of cells encapsulated in picoliter droplets in fluorocarbon oil. The use of fluorocarbon oil permitted high cell viability and little loss of the transfection reagent into the oil phase. We varied the incubation time inside droplets, the DNA concentration, and the droplet size. After optimization, we were able to achieve similar transfection efficiency in droplets to that in the bulk solution. Interestingly, the transfection efficiency increased with smaller droplets, suggesting effects from either the microscale confinement or the surface-to-volume ratio.


Assuntos
Fluorocarbonos/química , Óleos/química , Transfecção , Animais , Células CHO , Sobrevivência Celular , Células Cultivadas , Cricetinae , DNA/análise , Microfluídica , Água/química
17.
Oncol Lett ; 22(2): 583, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34122634

RESUMO

The aim of the present study was to investigate the expression and prognostic value of microRNA-135a (miR-135a) and matrix metalloproteinase-13 (MMP-13) in serum of colon cancer (CC). A total of 117 cases of patients admitted to Sheng Li Oil Field Central Hospital from May 2015 to May 2017 were enrolled in the research group (RG), and 120 cases of subjects undergoing normal health examination were included in the control group (CG). The expression of miR-135 and MMP-13 in peripheral blood of the two groups were compared, and their values were analyzed. It was found that miR-135a was decreased and MMP-13 was increased in the RG (P<0.050), both of which were closely related to the pathological features and prognosis of CC (P<0.050), and was also significantly correlated with CEA (P<0.001). ROC curve analysis showed that both of them had great predictive value for the occurrence, prognosis and death of CC. In conclusion, miR-135a was low expressed in CC, while MMP-13 was increased in CC, suggesting that the combined detection of the two had a good diagnostic effect on the occurrence of CC, and was closely related to the prognosis of CCC patients, which might be an excellent potential indicator for the diagnosis and treatment of CC in the future.

18.
Adv Nanobiomed Res ; 1(11)2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34870282

RESUMO

Triptolide (TPL) is a small molecule isolated from a traditional Chinese herb Tripterygium wilfordii Hook F and shows excellent anticancer effect for pancreatic cancer cells. However, the poor water solubility and severe liver toxicity of TPL hindered its clinical application. In this study, TPL was covalently conjugated to a polymer and entrapped inside the core of the TPL nanogel (nTPL) to protect it from premature leakage during blood circulation. With the help of lactobionic acid (LBA), nTPL-LBA could selectively target the tumors in an orthotopic pancreatic cancer mouse model. TPL could be subsequently released intracellularly in its original form due to the presence of elevated intracellular esterase and GSH, and eventually kills cancer cells. nTPL-LBA treatment reduced tumor burden by 99% while not introducing TPL associated liver and kidney toxicities. Most importantly, more than half of the nTPL-LBA treated animals were tumor-free, suggesting that nTPL-LBA is an effective approach in eradicating pancreatic cancer.

19.
J Alzheimers Dis ; 83(4): 1415-1429, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34219711

RESUMO

BACKGROUND: Anxious-depressive-like behavior has been recognized as an early endophenotype in Alzheimer's disease (AD). Recent studies support early treatment of anxious-depressive-like behavior as a potential target to alleviate memory loss and reduce the risk of developing dementia. We hypothesize that photobiomodulation (PBM) could be an effective method to alleviate depression and anxiety at the early stage of AD pathogenesis. OBJECTIVE: To analyze the effect of PBM treatment on anxious-depressive-like behavior at the early stage of AD. METHODS: Using a novel transgenic AD rat model, animals were divided into wild-type, AD+sham PBM, and AD+PBM groups. Two-minute daily PBM (irradiance: 25 mW/cm2 and fluence: 3 J/cm2 at the cortical level) was applied transcranially to the brain of AD animals from 2 months of age to 10 months of age. After completing PBM treatment at 10 months of age, behavioral tests were performed to measure learning, memory, and anxious-depressive-like behavior. Neuronal apoptosis, neuronal degeneration, neuronal damage, mitochondrial function, neuroinflammation, and oxidative stress were measured to test the effects of PBM on AD animals. RESULTS: Behavioral tests showed that: 1) no spatial memory deficits were detected in TgF344 rats at 10 months of age; 2) PBM alleviated anxious-depressive-like behavior in TgF344 rats; 3) PBM attenuated neuronal damage, degeneration, and apoptosis; and 4) PBM suppresses neuroinflammation and oxidative stress. CONCLUSION: Our findings support our hypothesis that PBM could be an effective method to alleviate depression and anxiety during the early stage of AD development. The mechanism underlying these beneficial effects may be due to the improvement of mitochondria function and integrity and the inhibition of neuroinflammation and oxidative stress.


Assuntos
Ansiedade/prevenção & controle , Depressão/prevenção & controle , Terapia com Luz de Baixa Intensidade , Ratos Transgênicos , Doença de Alzheimer/radioterapia , Animais , Apoptose , Modelos Animais de Doenças , Humanos , Masculino , Aprendizagem em Labirinto , Mitocôndrias/efeitos da radiação , Neurônios/efeitos da radiação , Estresse Oxidativo/efeitos da radiação , Ratos
20.
Biosens Bioelectron ; 181: 113134, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33761415

RESUMO

The coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread into a global pandemic. Early and accurate diagnosis and quarantine remain the most effective mitigation strategy. Although reverse transcriptase polymerase chain reaction (RT-qPCR) is the gold standard for COVID-19 diagnosis, recent studies suggest that nucleic acids were undetectable in a significant number of cases with clinical features of COVID-19. Serologic assays that detect human antibodies to SARS-CoV-2 serve as a complementary method to diagnose these cases, as well as to identify asymptomatic cases and qualified convalescent serum donors. However, commercially available enzyme-linked immunosorbent assays (ELISA) are laborious and non-quantitative, while point-of-care assays suffer from low detection accuracy. To provide a serologic assay with high performance and portability for potential point-of-care applications, we developed DNA-assisted nanopore sensing for quantification of SARS-CoV-2 related antibodies in human serum. Different DNA structures were used as detection reporters for multiplex quantification of immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies against the nucleocapsid protein of SARS-CoV-2 in serum specimens from patients with conformed or suspected infection. Comparing to a clinically used point-of-care assay and an ELISA assay, our technology can reliably quantify SARS-CoV-2 antibodies with higher accuracy, large dynamic range, and potential for assay automation.


Assuntos
Anticorpos Antivirais/análise , Técnicas Biossensoriais , Teste para COVID-19/métodos , COVID-19/diagnóstico , Nanoporos , DNA , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/análise , Imunoglobulina M/análise , SARS-CoV-2 , Sensibilidade e Especificidade
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