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1.
Cell ; 184(20): 5215-5229.e17, 2021 09 30.
Article in English | MEDLINE | ID: mdl-34559986

ABSTRACT

Estrogen receptor α (ERα) is a hormone receptor and key driver for over 70% of breast cancers that has been studied for decades as a transcription factor. Unexpectedly, we discover that ERα is a potent non-canonical RNA-binding protein. We show that ERα RNA binding function is uncoupled from its activity to bind DNA and critical for breast cancer progression. Employing genome-wide cross-linking immunoprecipitation (CLIP) sequencing and a functional CRISPRi screen, we find that ERα-associated mRNAs sustain cancer cell fitness and elicit cellular responses to stress. Mechanistically, ERα controls different steps of RNA metabolism. In particular, we demonstrate that ERα RNA binding mediates alternative splicing of XBP1 and translation of the eIF4G2 and MCL1 mRNAs, which facilitates survival upon stress conditions and sustains tamoxifen resistance of cancer cells. ERα is therefore a multifaceted RNA-binding protein, and this activity transforms our knowledge of post-transcriptional regulation underlying cancer development and drug response.


Subject(s)
Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Drug Resistance, Neoplasm , Estrogen Receptor alpha/metabolism , RNA-Binding Proteins/metabolism , Animals , Base Sequence , Breast Neoplasms/genetics , Cell Line, Tumor , Cell Survival/drug effects , Cell Survival/genetics , Disease Progression , Drug Resistance, Neoplasm/drug effects , Drug Resistance, Neoplasm/genetics , Estrogen Receptor alpha/chemistry , Eukaryotic Initiation Factor-4G/genetics , Eukaryotic Initiation Factor-4G/metabolism , Female , Gene Expression Regulation, Neoplastic/drug effects , Genomics , Humans , Mice, Inbred NOD , Myeloid Cell Leukemia Sequence 1 Protein/genetics , Myeloid Cell Leukemia Sequence 1 Protein/metabolism , Oncogenes , Protein Binding/drug effects , Protein Domains , RNA Splicing/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Stress, Physiological/drug effects , Stress, Physiological/genetics , Tamoxifen/pharmacology , X-Box Binding Protein 1/metabolism
2.
Mol Cell ; 82(14): 2536-2538, 2022 07 21.
Article in English | MEDLINE | ID: mdl-35868253

ABSTRACT

In this issue of Molecular Cell, Liu et al. (2022) report that 5'-tRFCys, a stress-induced transfer RNA-derived RNA fragment (tRF) derived from the 5' halves of cysteine tRNAs, regulates post-transcriptional gene expression, enabling the survival and lung metastasis formation of breast cancers.


Subject(s)
Breast Neoplasms , RNA-Binding Proteins , Breast Neoplasms/genetics , Female , Humans , Phosphoproteins/genetics , Phosphoproteins/metabolism , RNA, Transfer/genetics , RNA, Transfer/metabolism , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism , Nucleolin
3.
Mol Cell ; 75(5): 967-981.e9, 2019 09 05.
Article in English | MEDLINE | ID: mdl-31300274

ABSTRACT

Post-transcriptional regulation of RNA stability is a key step in gene expression control. We describe a regulatory program, mediated by the RNA binding protein TARBP2, that controls RNA stability in the nucleus. TARBP2 binding to pre-mRNAs results in increased intron retention, subsequently leading to targeted degradation of TARBP2-bound transcripts. This is mediated by TARBP2 recruitment of the m6A RNA methylation machinery to its target transcripts, where deposition of m6A marks influences the recruitment of splicing regulators, inhibiting efficient splicing. Interactions between TARBP2 and the nucleoprotein TPR then promote degradation of these TARBP2-bound transcripts by the nuclear exosome. Additionally, analysis of clinical gene expression datasets revealed a functional role for TARBP2 in lung cancer. Using xenograft mouse models, we find that TARBP2 affects tumor growth in the lung and that this is dependent on TARBP2-mediated destabilization of ABCA3 and FOXN3. Finally, we establish ZNF143 as an upstream regulator of TARBP2 expression.


Subject(s)
Lung Neoplasms/metabolism , Neoplasm Proteins/metabolism , RNA Splicing , RNA Stability , RNA, Neoplasm/metabolism , RNA-Binding Proteins/metabolism , ATP-Binding Cassette Transporters/genetics , ATP-Binding Cassette Transporters/metabolism , Animals , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Line, Tumor , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/metabolism , Humans , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Mice , Mice, Inbred NOD , Mice, SCID , Neoplasm Proteins/genetics , RNA, Neoplasm/genetics , RNA-Binding Proteins/genetics , Trans-Activators/genetics , Trans-Activators/metabolism
4.
Article in English | MEDLINE | ID: mdl-38641368

ABSTRACT

BACKGROUND: Rapid eye movement (REM) sleep behaviour disorder (RBD) is one of the most common sleep problems and represents a key prodromal marker in Parkinson's disease (PD). It remains unclear whether and how basal ganglia nuclei, structures that are directly involved in the pathology of PD, are implicated in the occurrence of RBD. METHOD: Here, in parallel with whole-night video polysomnography, we recorded local field potentials from two major basal ganglia structures, the globus pallidus internus and subthalamic nucleus, in two cohorts of patients with PD who had varied severity of RBD. Basal ganglia oscillatory patterns during RBD and REM sleep without atonia were analysed and compared with another age-matched cohort of patients with dystonia that served as controls. RESULTS: We found that beta power in both basal ganglia nuclei was specifically elevated during REM sleep without atonia in patients with PD, but not in dystonia. Basal ganglia beta power during REM sleep positively correlated with the extent of atonia loss, with beta elevation preceding the activation of chin electromyogram activities by ~200 ms. The connectivity between basal ganglia beta power and chin muscular activities during REM sleep was significantly correlated with the clinical severity of RBD in PD. CONCLUSIONS: These findings support that basal ganglia activities are associated with if not directly contribute to the occurrence of RBD in PD. Our study expands the understanding of the role basal ganglia played in RBD and may foster improved therapies for RBD by interrupting the basal ganglia-muscular communication during REM sleep in PD.

5.
J Fluoresc ; 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39052155

ABSTRACT

A kind of nitrogen and sulfur co-doped CDs (N, S-CDs) was facilely synthesized using thiourea and citric acid as precursors, which established an "on-off-on" fluorescence probe to sequential detecting mercury and iodine ions inside water and biology samples. Under 360 nm excitation, CDs emit blue fluorescence with an optimal emission peak of 425 nm (on). The fluorescence of CDs experiences a significant quenching effect upon interaction with Hg2+ ions due to the electron transfer between CDs and Hg2+. This quenching effect is subsequently recovered upon the addition of I- owing to the formation of complexes between Hg2+ and I-. The probe exhibits high selectivity and sensitivity toward Hg2+ and I- with broad linearity in the range of 5-50 µM and 15-60 µM, respectively, and a low detection limit of 14.336 nM and 38.213 nM, respectively. The constructed fluorescence probe N, S-CDs has been successfully applied to the detection of Hg2+ and I- in water and biological samples with great recoveries. More importantly, the bioimaging study demonstrated that N, S-CDs are suitable for live monitoring in biological imaging scenarios of Hg2+ and I- in living cells.

6.
Phytother Res ; 38(3): 1313-1328, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38194947

ABSTRACT

5-Fluorouracil is a commonly used chemotherapy drug for colorectal cancer. Resistance to 5-Fluorouracil remains a challenge. This research aimed to explore the mechanism of 5-Fluorouracil resistance in colorectal cancer. RT-qPCR and Western blot were used to determine the RNA and protein expression in both cells and exosome. Assays in vitro and in vivo were performed to measure the role of miR-149-5p in colorectal cancer cells. RIP, luciferase activity report, and RNA pulldown assay were applied to detect the association of PTOV1-AS1, SUV39H1, miR-149-5p, and FOXM1. MiR-149-5p was down-expressed in 5-Fluorouracil-resistant cells. MiR-149-5p enhanced the effectiveness of 5-Fluorouracil both in vitro and in vivo. Sensitive colorectal cancer cells released exosomal miR-149-5p to sensitize resistant cells to chemotherapy. Mechanistically, miR-149-5p targeted the FOXM1 to inactivate Wnt/ß-catenin pathway, and PTOV1-AS1 recruited SUV39H1 to suppress miR-149-5p transcription, in turn activating Wnt/ß-catenin pathway, and forming a positive feedback loop with FOXM1. PTOV1-AS1 inhibits miR-149-5p by a positive feedback loop with FOXM1-mediated Wnt/ß-catenin pathway, which provides insights into a potential novel target for enhancing the effectiveness of chemotherapy in colorectal cancer patients.


Subject(s)
Colorectal Neoplasms , MicroRNAs , RNA, Long Noncoding , Humans , MicroRNAs/genetics , beta Catenin/metabolism , Cell Line, Tumor , Feedback , Cell Proliferation , Wnt Signaling Pathway , Fluorouracil , Colorectal Neoplasms/genetics , Gene Expression Regulation, Neoplastic , RNA, Long Noncoding/genetics , Neoplasm Proteins/metabolism , Biomarkers, Tumor/therapeutic use
7.
Int J Mol Sci ; 25(6)2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38542087

ABSTRACT

Currently, coronary artery bypass and reperfusion therapies are considered the gold standard in long-term treatments to restore heart function after acute myocardial infarction. As a drawback of these restoring strategies, reperfusion after an ischemic insult and sudden oxygen exposure lead to the exacerbated synthesis of additional reactive oxidative species and the persistence of increased oxidation levels. Attempts based on antioxidant treatment have failed to achieve an effective therapy for cardiovascular disease patients. The controversial use of vitamin C as an antioxidant in clinical practice is comprehensively systematized and discussed in this review. The dose-dependent adsorption and release kinetics mechanism of vitamin C is complex; however, this review may provide a holistic perspective on its potential as a preventive supplement and/or for combined precise and targeted therapeutics in cardiovascular management therapy.


Subject(s)
Ascorbic Acid , Myocardial Infarction , Humans , Reactive Oxygen Species , Ascorbic Acid/pharmacology , Ascorbic Acid/therapeutic use , Antioxidants/pharmacology , Antioxidants/therapeutic use , Vitamin E/therapeutic use , Oxidative Stress , Vitamins , Myocardial Infarction/drug therapy
8.
Neurobiol Dis ; 182: 106143, 2023 06 15.
Article in English | MEDLINE | ID: mdl-37146835

ABSTRACT

BACKGROUND: Sleep disturbances are highly prevalent in movement disorders, potentially due to the malfunctioning of basal ganglia structures. Pallidal deep brain stimulation (DBS) has been widely used for multiple movement disorders and been reported to improve sleep. We aimed to investigate the oscillatory pattern of pallidum during sleep and explore whether pallidal activities can be utilized to differentiate sleep stages, which could pave the way for sleep-aware adaptive DBS. METHODS: We directly recorded over 500 h of pallidal local field potentials during sleep from 39 subjects with movement disorders (20 dystonia, 8 Huntington's disease, and 11 Parkinson's disease). Pallidal spectrum and cortical-pallidal coherence were computed and compared across sleep stages. Machine learning approaches were utilized to build sleep decoders for different diseases to classify sleep stages through pallidal oscillatory features. Decoding accuracy was further associated with the spatial localization of the pallidum. RESULTS: Pallidal power spectra and cortical-pallidal coherence were significantly modulated by sleep-stage transitions in three movement disorders. Differences in sleep-related activities between diseases were identified in non-rapid eye movement (NREM) and REM sleep. Machine learning models using pallidal oscillatory features can decode sleep-wake states with over 90% accuracy. Decoding accuracies were higher in recording sites within the internus-pallidum than the external-pallidum, and can be precited using structural (P < 0.0001) and functional (P < 0.0001) whole-brain neuroimaging connectomics. CONCLUSION: Our findings revealed strong sleep-stage dependent distinctions in pallidal oscillations in multiple movement disorders. Pallidal oscillatory features were sufficient for sleep stage decoding. These data may facilitate the development of adaptive DBS systems targeting sleep problems that have broad translational prospects.


Subject(s)
Deep Brain Stimulation , Dystonia , Dystonic Disorders , Parkinson Disease , Humans , Globus Pallidus , Parkinson Disease/complications , Parkinson Disease/therapy , Deep Brain Stimulation/methods , Sleep
9.
Biomacromolecules ; 24(2): 797-806, 2023 02 13.
Article in English | MEDLINE | ID: mdl-36642871

ABSTRACT

At-home tooth whitening solutions with good efficacy and biosafety are highly desirable to meet the ever-growing demand for aesthetic dentistry. As a promising alternative to the classic peroxide bleaching that may damage tooth enamel and gums, piezocatalysis has been recently proposed to realize non-destructive whitening by toothbrushing with piezoelectrical particles. However, traditional particles either pose potential threats to human health or exhibit low piezoresponse to weak mechanical stimuli in the toothbrushing. Here, biocompatible and biodegradable polylactide particles constructed from interlocking crystalline lamellae have been hierarchically designed as next-generation whitening materials with ultra-high piezocatalytic activity and biosafety. By simultaneously controlling the chain conformation within lamellae and the porosity of such unique lamellae network at the nano- and microscales, the particles possessing unprecedented piezoelectricity have been successfully prepared due to the markedly increased dipole alignment, mechanical deformability, and specific surface area. The piezoelectric output can reach as high as 18.8 V, nearly 50 times higher than that of common solid polylactide particles. Consequently, their piezocatalytic effect can be readily activated by a toothbrush to rapidly clean the teeth stained with black tea and coffee, without causing detectable enamel damage. Furthermore, these particles have no cytotoxicity. This work presents a paradigm for achieving high piezoelectric activity in polylactide, which enables its practical application in tooth whitening.


Subject(s)
Tooth Bleaching , Tooth Discoloration , Tooth , Humans , Containment of Biohazards , Hydrogen Peroxide
10.
Int J Mol Sci ; 24(9)2023 May 06.
Article in English | MEDLINE | ID: mdl-37176085

ABSTRACT

Extracellular collagen remodeling is one of the central mechanisms responsible for the structural and compositional coherence of myocardium in patients undergoing myocardial infarction (MI). Activated primary cardiac fibroblasts following myocardial infarction are extensively investigated to establish anti-fibrotic therapies to improve left ventricular remodeling. To systematically assess vitamin C functions as a potential modulator involved in collagen fibrillogenesis in an in vitro model mimicking heart tissue healing after MI. Mouse primary cardiac fibroblasts were isolated from wild-type C57BL/6 mice and cultured under normal and profibrotic (hypoxic + transforming growth factor beta 1) conditions on freshly prepared coatings mimicking extracellular matrix (ECM) remodeling during healing after an MI. At 10 µg/mL, vitamin C reprogramed the respiratory mitochondrial metabolism, which is effectively associated with a more increased accumulation of intracellular reactive oxygen species (iROS) than the number of those generated by mitochondrial reactive oxygen species (mROS). The mRNA/protein expression of subtypes I, III collagen, and fibroblasts differentiations markers were upregulated over time, particularly in the presence of vitamin C. The collagen substrate potentiated the modulator role of vitamin C in reinforcing the structure of types I and III collagen synthesis by reducing collagen V expression in a timely manner, which is important in the initiation of fibrillogenesis. Altogether, our study evidenced the synergistic function of vitamin C at an optimum dose on maintaining the equilibrium functionality of radical scavenger and gene transcription, which are important in the initial phases after healing after an MI, while modulating the synthesis of de novo collagen fibrils, which is important in the final stage of tissue healing.


Subject(s)
Ascorbic Acid , Myocardial Infarction , Mice , Animals , Ascorbic Acid/pharmacology , Ascorbic Acid/metabolism , Reactive Oxygen Species/metabolism , Mice, Inbred C57BL , Myocardial Infarction/metabolism , Myocardium/metabolism , Collagen/metabolism , Fibroblasts/metabolism , Vitamins/metabolism , Ventricular Remodeling/physiology
11.
J Biol Chem ; 296: 100417, 2021.
Article in English | MEDLINE | ID: mdl-33587951

ABSTRACT

Induction of fetal hemoglobin to overcome adult ß-globin gene deficiency is an effective therapeutic strategy to ameliorate human ß-hemoglobinopathies. Previous work has revealed that fetal γ-globin can be translationally induced via integrated stress signaling, but other studies have indicated that activating stress may eventually suppress γ-globin expression transcriptionally. The mechanism by which γ-globin expression is regulated at the translational level remains largely unknown, limiting our ability to determine whether activating stress is a realistic therapeutic option for these disorders. In this study, we performed a functional CRISPR screen targeting protein arginine methyltransferases (PRMTs) to look for changes in γ-globin expression in K562 cells. We not only discovered that several specific PRMTs may block γ-globin transcription, but also revealed PRMT1 as a unique family member that is able to suppress γ-globin synthesis specifically at the translational level. We further identified that a non-AUG uORF within the 5' untranslated region of γ-globin serves as a barrier for translation, which is bypassed upon PRMT1 deficiency. Finally, we found that this novel mechanism of γ-globin suppression could be pharmacologically targeted by the PRMT1 inhibitor, furamidine dihydrochloride. These data raise new questions regarding methyltransferase function and may offer a new therapeutic direction for ß-hemoglobinopathies.


Subject(s)
Protein-Arginine N-Methyltransferases/metabolism , Repressor Proteins/metabolism , gamma-Globins/metabolism , Fetal Hemoglobin/biosynthesis , Fetal Hemoglobin/genetics , Fetal Hemoglobin/pharmacology , Gene Expression/genetics , Gene Expression Regulation/genetics , HEK293 Cells , Humans , K562 Cells , Methyltransferases/metabolism , Protein Biosynthesis/genetics , Protein-Arginine N-Methyltransferases/antagonists & inhibitors , Protein-Arginine N-Methyltransferases/genetics , Protein-Arginine N-Methyltransferases/physiology , Repressor Proteins/genetics , Repressor Proteins/physiology , beta-Globins/metabolism , gamma-Globins/genetics
12.
Int J Mol Sci ; 23(23)2022 Nov 23.
Article in English | MEDLINE | ID: mdl-36498897

ABSTRACT

Myocardial infarction is remains the leading cause of death in developed countries. Recent data show that the composition of the extracellular matrix might differ despite similar heart function and infarction sizes. Because collagen is the main component of the extracellular matrix, we hypothesized that changes in inflammatory cell recruitment influence the synthesis of different collagen subtypes in myofibroblasts, thus changing the composition of the scar. We found that neutrophils sustain the proliferation of fibroblasts, remodeling, differentiation, migration and inflammation, predominantly by IL-1 and PPARγ pathways (n = 3). They also significantly inhibit the mRNA expression of fibrillar collagen, maintaining a reduced stiffness in isolated myofibroblasts (n = 4-5). Reducing the neutrophil infiltration in CCR1-/- resulted in increased mRNA expression of collagen 11, moderate expression of collagen 19 and low expression of collagen 13 and 26 in the scar 4 weeks post infarction compared with other groups (n = 3). Mononuclear cells increased the synthesis of all collagen subtypes and upregulated the NF-kB, angiotensin II and PPARδ pathways (n = 3). They increased the synthesis of collagen subtypes 1, 3, 5, 16 and 23 but reduced the expression of collagens 5 and 16 (n = 3). CCR2-/- scar tissue showed higher levels of collagen 13 (n = 3), in association with a significant reduction in stiffness (n = 4-5). Upregulation of the inflammation-related genes in myofibroblasts mostly modulated the fibrillar collagen subtypes, with less effect on the FACIT, network-forming and globular subtypes (n = 3). The upregulation of proliferation and differentiation genes in myofibroblasts seemed to be associated only with the fibrillar collagen subtype, whereas angiogenesis-related genes are associated with fibrillar, network-forming and multiplexin subtypes. In conclusion, although we intend for our findings to deepen the understanding of the mechanism of healing after myocardial infarction and scar formation, the process of collagen synthesis is highly complex, and further intensive investigation is needed to put together all the missing puzzle pieces in this still incipient knowledge process.


Subject(s)
Myocardial Infarction , Humans , Myocardial Infarction/metabolism , Cicatrix/pathology , Collagen/genetics , Collagen/metabolism , Extracellular Matrix/metabolism , Myofibroblasts/metabolism , Fibroblasts/metabolism , Collagen Type I/metabolism , RNA, Messenger/metabolism , Myocardium/metabolism
13.
Molecules ; 27(9)2022 Apr 21.
Article in English | MEDLINE | ID: mdl-35566032

ABSTRACT

Brain tumors are the most widespread malignancies in children around the world. Chemotherapy plays a critical role in the treatment of these tumors. Although the current chemotherapy process has a remarkable outcome for a certain subtype of brain tumor, improving patient survival is still a major challenge. Further intensive treatment with conventional non-specific chemotherapy could cause additional adverse reactions without significant advancement in survival. Recently, patient derived brain tumor, xenograft, and whole genome analysis using deep sequencing technology has made a significant contribution to our understanding of cancer treatment. This realization has changed the focus to new agents, targeting the molecular pathways that are critical to tumor survival or proliferation. Thus, many novel drugs targeting epigenetic regulators or tyrosine kinase have been developed. These selective drugs may have less toxicity in normal cells and are expected to be more effective than non-specific chemotherapeutics. This review will summarize the latest novel targets and corresponding candidate drugs, which are promising chemotherapy for brain tumors according to the biological insights.


Subject(s)
Antineoplastic Agents , Brain Neoplasms , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Brain Neoplasms/drug therapy , Brain Neoplasms/genetics , Child , Humans , Protein-Tyrosine Kinases
14.
Bull Environ Contam Toxicol ; 106(5): 825-831, 2021 May.
Article in English | MEDLINE | ID: mdl-33247787

ABSTRACT

Monitoring water environmental quality of large rivers is the basis of river evaluation and local environmental protection worldwide. This study compared the water quality of the Rhine and the Yangtze River, two of the world's most important arteries, based on monitoring data collected from their monitor stations from 2007 to 2018. Dissolved oxygen (DO), pH, chemical oxygen demand (COD)/dissolved organic carbon (DOC) and ammonia-nitrogen (NH3-N) were used to evaluate their water quality. The changing trend, the temporal and special patterns were also analyzed. It was found that the overall water quality of the Rhine in the last decade (p = 0.95) was better than the Yangtze (p = 1.01). Notably, CODMn and NH3-N were identified as main pollution factors of the Rhine and the Yangtze, respectively. This study provided information for water quality modelling, therefore might be helpful for the water quality management of China.


Subject(s)
Rivers , Water Pollutants, Chemical , Biological Oxygen Demand Analysis , China , Environmental Monitoring , Water Pollutants, Chemical/analysis , Water Quality
15.
Opt Lett ; 43(11): 2563-2566, 2018 Jun 01.
Article in English | MEDLINE | ID: mdl-29856430

ABSTRACT

We report a high-energy single-frequency deep-ultraviolet (DUV) solid-state laser at 167.079 nm by the eighth-harmonic generation of a diode-pumped Nd:LGGG laser. A maximum DUV laser output energy of 1.5 µJ at a 5 Hz repetition rate with a 200 µs pulse duration is achieved. The central wavelength of the DUV laser is located at 167.079 nm and can be finely tuned from 167.075 to 167.083 nm. The linewidth is estimated to be 0.025 pm. To the best of our knowledge, this is the first Letter reporting a high-energy single-frequency solid-state DUV laser below 170 nm. The successful demonstration of the high-energy single-frequency DUV laser source with the unique wavelength is useful for direct detection of a Al+27 ion via resonance fluorescence in a multi-ion optical clock.

16.
Cell Physiol Biochem ; 43(3): 1126-1139, 2017.
Article in English | MEDLINE | ID: mdl-28977798

ABSTRACT

BACKGROUND/AIMS: Although small cell lung cancer (SCLC) is sensitive to initial chemotherapy, patients experience tumor recurrence and metastasis, leading to treatment failure. Autophagy as a protective pattern for cell survival in the harsh environment plays an important role in chemoresistance. However, the role of Beclin-1, a key regulator of autophagy in the drug-resistance of SCLC cells is still poorly understood. In the current study, we focused on the effect and regulation of Beclin-1 in chemoresistance of SCLC cells. METHODS: We analyzed the levels of Beclin-1 in etoposide/cisplatin (EP) -resistant and -sensitive cell lines, as well as the relationship between Beclin-1 and patients' chemosensitivity. The function of Beclin-1 in chemoresistant SCLC cells in vitro was measured by MTT, WB, colony formation and flow cytometric analysis. Further rescue experiment was performed after co-transfected with siBeclin-1 and miR-30a mimics or inhibitor. RESULTS: Beclin-1 was upregulated in drug-resistant cells and patients with lower sensitivity to etoposide/cisplatin therapy. Downregulated Beclin-1 attenuated drug sensitivity and colony formation ability of chemoresistant cells. Moreover, inhibition of Beclin-1 resulted in a dramatic decline of autophagy and increase of apoptosis in drug-resistant cells, accompanied by a remarkable reduction in S phase and a raise in G2/M phase of cell cycle. The transfection with miR-30a-5p mimics exhibited an opposite effect. In addition, inhibition of Beclin-1 could partly reverse the effect induced by miR-30a-5p suppression in drug-sensitive cells. CONCLUSION: Beclin-1 regulated by miR-30a-5p plays a notable role in the drug-resistance of SCLC. Inhibition of Beclin-1 by induction of miR-30a-5p may improve the therapeutic outcome via resensitizing the drug-resistant cells to chemotherapy in SCLC.


Subject(s)
Beclin-1/metabolism , Lung Neoplasms/pathology , MicroRNAs/metabolism , Small Cell Lung Carcinoma/pathology , 3' Untranslated Regions , Antagomirs/metabolism , Apoptosis/drug effects , Base Sequence , Beclin-1/antagonists & inhibitors , Beclin-1/genetics , Cell Line, Tumor , Cisplatin/pharmacology , Cisplatin/therapeutic use , Drug Resistance, Neoplasm/drug effects , Etoposide/pharmacology , Etoposide/therapeutic use , Female , G2 Phase Cell Cycle Checkpoints/drug effects , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , M Phase Cell Cycle Checkpoints/drug effects , Male , MicroRNAs/antagonists & inhibitors , MicroRNAs/genetics , Middle Aged , RNA Interference , RNA, Small Interfering/metabolism , Sequence Alignment , Small Cell Lung Carcinoma/drug therapy , Small Cell Lung Carcinoma/genetics , Up-Regulation/drug effects
17.
Mol Cell Proteomics ; 14(9): 2479-92, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26089344

ABSTRACT

Tyrosine kinases (TKs) are central regulators in cellular activities and perturbations of TK signaling contribute to oncogenesis. However, less than half of the TKs have been thoroughly studied and a global functional analysis of their proteomic portrait is lacking. Here we conducted a combined approach of RNA interference (RNAi) and stable isotope labeling with amino acids in cell culture (SILAC)-based quantitative proteomics to decode the TK-regulated proteome and associated signaling dynamics. As a result, a broad proteomic repertoire modulated by TKs was revealed, upon silencing of the 65 TKs expressed in MCF7 breast cancer cells. This yielded 10 new distinctive TK clusters according to similarity in TK-regulated proteome, each characterized by a unique signaling signature in contrast to previous classifications. We provide functional analyses and identify critical pathways for each cluster based on their common downstream targets. Analysis of different breast cancer subtypes showed distinct correlations of each cluster with clinical outcome. From the significantly up- and down-regulated proteins, we identified a number of markers of drug sensitivity and resistance. These data supports the role of TKs in regulating major aspects of cellular activity, but also reveals redundancy in signaling, explaining why kinase inhibitors alone often fail to achieve their clinical aims. The TK-SILACepedia provides a comprehensive resource for studying the global function of TKs in cancer.


Subject(s)
Breast Neoplasms/metabolism , Isotope Labeling/methods , Protein-Tyrosine Kinases/metabolism , Proteome/analysis , Proteomics/methods , RNA Interference , Amino Acids/chemistry , Cell Culture Techniques , Cell Line, Tumor , Doxorubicin/pharmacology , Drug Resistance, Neoplasm , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , MCF-7 Cells , Signal Transduction
18.
Breast Cancer Res Treat ; 151(3): 555-68, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26022350

ABSTRACT

Kinase suppressor of Ras 1 (KSR1) has been implicated in tumorigenesis in multiple cancers, including skin, pancreatic and lung carcinomas. However, our recent study revealed a role of KSR1 as a tumour suppressor in breast cancer, the expression of which is potentially correlated with chemotherapy response. Here, we aimed to further elucidate the KSR1-regulated signalling in response to genotoxic agents in breast cancer. Stable isotope labelling by amino acids in cell culture (SILAC) coupled to high-resolution mass spectrometry (MS) was implemented to globally characterise cellular protein levels induced by KSR1 in the presence of doxorubicin or etoposide. The acquired proteomic signature was compared and GO-STRING analysis was subsequently performed to illustrate the activated functional signalling networks. Furthermore, the clinical associations of KSR1 with identified targets and their relevance in chemotherapy response were examined in breast cancer patients. We reveal a comprehensive repertoire of thousands of proteins identified in each dataset and compare the unique proteomic profiles as well as functional connections modulated by KSR1 after doxorubicin (Doxo-KSR1) or etoposide (Etop-KSR1) stimulus. From the up-regulated top hits, several proteins, including STAT1, ISG15 and TAP1 are also found to be positively associated with KSR1 expression in patient samples. Moreover, high KSR1 expression, as well as high abundance of these proteins, is correlated with better survival in breast cancer patients who underwent chemotherapy. In aggregate, our data exemplify a broad functional network conferred by KSR1 with genotoxic agents and highlight its implication in predicting chemotherapy response in breast cancer.


Subject(s)
Breast Neoplasms/metabolism , Mutagens/pharmacology , Protein Kinases/metabolism , Proteome , Proteomics , Signal Transduction/drug effects , Antineoplastic Agents/pharmacology , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Breast Neoplasms/mortality , Cell Line, Tumor , Cluster Analysis , Doxorubicin/pharmacology , Etoposide/pharmacology , Female , Gene Expression , Gene Expression Regulation, Neoplastic , Gene Regulatory Networks , Humans , Prognosis , Protein Kinases/genetics , Proteomics/methods , Survival Analysis
19.
Expert Rev Proteomics ; 11(6): 713-31, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25345469

ABSTRACT

Large-scale transcriptome and epigenome analyses have been widely utilized to discover gene alterations implicated in cancer development at the genetic level. However, mapping of signaling dynamics at the protein level is likely to be more insightful and needed to complement massive genomic data. Stable isotope labeling with amino acids in cell culture (SILAC)-based proteomic analysis represents one of the most promising comparative quantitative methods that has been extensively employed in proteomic research. This technology allows for global, robust and confident identification and quantification of signal perturbations important for the progress of human diseases, particularly malignancies. The present review summarizes the latest applications of in vitro and in vivo SILAC-based proteomics in identifying global proteome/phosphoproteome and genome-wide protein-protein interactions that contribute to oncogenesis, highlighting the recent advances in dissecting signaling dynamics in cancer.


Subject(s)
Neoplasms/metabolism , Proteome/metabolism , Amino Acids/chemistry , Animals , Carcinogenesis/metabolism , Cell Culture Techniques , Disease Progression , Humans , Isotope Labeling , Phosphorylation , Protein Interaction Maps , Proteome/chemistry , Proteomics , Signal Transduction
20.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(9): 1064-8, 2014 Sep.
Article in Zh | MEDLINE | ID: mdl-25335329

ABSTRACT

OBJECTIVE: To study the effect of Shugan Jiangu Recipe (SJR) on bone mineral density (BMD) and serum bone metabolic biochemical markers in postmenopausal breast cancer patients with osteopenia. METHODS: Totally 38 patients of postmenopausal women with breast cancer, who received aromatase inhibitors (AIs), were assigned to the treatment group (21 cases) and the control group (17 cases) by using random digit table. All patients took Caltrate D Tablet (containing Ca 600 mg and Vit D3 125 IU), one tablet daily. Patients in the treatment group took SJR, 6 g each time, twice daily for 6 successive months. The bone mineral density (BMD) level was detected before treatment and at months 6 after treatment. Levels of bone alkaline phosphatase (BALP), bone gla protein (BGP), tartrate-resistant acid phosphatase (TRAP), and C-terminal telopeptide of type II collagen (CTX-II) were detected by enzyme linked immunosorbent assay (ELISA). The drug safety was also assessed. RESULTS: Compared with before treatment, BMD of L2-4 and femur neck obviously increased in the treatment group at month 6 after treatment (P < 0.01), serum BALP and TRAP decreased (P < 0.05). Compared with before treatment, BMD of L2-4 and femur neck obviously decreased in the control group at month 6 after treatment (P < 0.05), serum BALP and TRAP increased (P < 0.01). Compared with the control group, lumbar and femur neck BMD obviously increased, serum levels of BGP and BALP obviously decreased, and serum levels of CTX-II and TRAP obviously increased in the treatment group at month 6 after treatment (P < 0.01). No serious adverse event occurred during the treatment period. Bone fracture occurred in one case of the control group (5.8%). CONCLUSION: SJR could attenuate bone loss of postmenopausal women with breast cancer who received AIs, increase BMD and improve abnormal bone metabolism.


Subject(s)
Aromatase Inhibitors/adverse effects , Bone Density/drug effects , Drugs, Chinese Herbal/therapeutic use , Osteoporosis, Postmenopausal/prevention & control , Acid Phosphatase/blood , Aged , Alkaline Phosphatase/blood , Bone and Bones/drug effects , Bone and Bones/metabolism , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Collagen Type II/blood , Female , Humans , Isoenzymes/blood , Middle Aged , Osteocalcin/blood , Osteoporosis, Postmenopausal/chemically induced , Peptide Fragments/blood , Tartrate-Resistant Acid Phosphatase
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