scholarly journals Platelet-Derived Microvesicles Promote VSMC Dedifferentiation After Intimal Injury via Src/Lamtor1/mTORC1 Signaling

2021 ◽  
Vol 9 ◽  
Author(s):  
Ji-Ting Liu ◽  
Han Bao ◽  
Yang-Jing Fan ◽  
Zi-Tong Li ◽  
Qing-Ping Yao ◽  
...  
Keyword(s):  
Intimal Hyperplasia ◽  
Phenotypic Switch ◽  
Proteomic Data ◽  
Activated Platelets ◽  
Mtorc1 Signaling ◽  
Intimal Injury ◽  
Underlying Mechanisms ◽  
Interfering Rna

Phenotypic switch of vascular smooth muscle cells (VSMCs) is important in vascular remodeling which causes hyperplasia and restenosis after intimal injury. Platelets are activated at injured intima and secrete platelet-derived microvesicles (PMVs). Herein, we demonstrated the role of PMVs in VSMC phenotypic switch and the potential underlying mechanisms. In vivo, platelets were locally adhered and activated at intimal injury site, while Lamtor1 was promoted and VSMCs were dedifferentiated. PMVs, collected from collagen-activated platelets in vitro which mimicked collagen exposure during intimal injury, promoted VSMC dedifferentiation, induced Lamtor1 expression, and activated mTORC1 signaling, reflected by the phosphorylation of two downstream targets, i.e., S6K and 4E-BP1. Knockdown of Lamtor1 with small interfering RNA attenuated these processes induced by PMVs. Based on the previously published proteomic data, Ingenuity Pathway Analysis revealed that Src may participate in regulating effects of PMVs. Src inhibitor significantly reversed the effects of PMVs on VSMC dedifferentiation, Lamtor1 expression and mTORC1 activation. Furthermore, in SMC-specific Lamtor1 knockout mice, intimal hyperplasia was markedly attenuated after intimal injury compared with the wild type. Our data suggested that PMVs secreted by activated platelets promoted VSMC dedifferentiation via Src/Lamtor1/mTORC1 signaling pathway. Lamtor1 may be a potential therapeutic target for intimal hyperplasia after injury.

scholarly journals Platelet-Derived Extracellular Vesicles Increase Col8a1 Secretion and Vascular Stiffness in Intimal Injury

2021 ◽  
Vol 9 ◽  
Author(s):  
Han Bao ◽  
Zi-Tong Li ◽  
Lei-Han Xu ◽  
Tong-Yue Su ◽  
Yue Han ◽  
...  
Keyword(s):  
Carotid Artery ◽  
Extracellular Vesicles ◽  
Neointimal Hyperplasia ◽  
Vascular Stiffness ◽  
Akt Pathway ◽  
Activated Platelets ◽  
Injury Model ◽  
Intimal Injury

The arterial mechanical microenvironment, including stiffness, is a crucial pathophysiological feature of vascular remodeling, such as neointimal hyperplasia after carotid endarterectomy and balloon dilatation surgeries. In this study, we examined changes in neointimal stiffness in a Sprague-Dawley rat carotid artery intimal injury model and revealed that extracellular matrix (ECM) secretion and vascular stiffness were increased. Once the endothelial layer is damaged in vivo, activated platelets adhere to the intima and may secrete platelet-derived extracellular vesicles (pEVs) and communicate with vascular smooth muscle cells (VSMCs). In vitro, pEVs stimulated VSMCs to promote collagen secretion and cell adhesion. MRNA sequencing analysis of a carotid artery intimal injury model showed that ECM factors, including col8a1, col8a2, col12a1, and elastin, were upregulated. Subsequently, ingenuity pathway analysis (IPA) was used to examine the possible signaling pathways involved in the formation of ECM, of which the Akt pathway played a central role. In vitro, pEVs activated Akt signaling through the PIP3 pathway and induced the production of Col8a1. MicroRNA (miR) sequencing of pEVs released from activated platelets revealed that 14 of the top 30 miRs in pEVs targeted PTEN, which could promote the activation of the Akt pathway. Further research showed that the most abundant miR targeting PTEN was miR-92a-3p, which promoted Col8a1 expression. Interestingly, knockdown of Col8a1 expression in vivo abrogated the increase in carotid artery stiffness and simultaneously increased the degree of neointimal hyperplasia. Our results revealed that pEVs may deliver miR-92a-3p to VSMCs to induce the production and secretion of Col8a1 via the PTEN/PIP3/Akt pathway, subsequently increasing vascular stiffness. Therefore, pEVs and key molecules may be potential therapeutic targets for treating neointimal hyperplasia.

A Comparison of the Effect of Decorsin and Two Disintegrins, Albolabrin and Eristostatin, on Platelet Function

1995 ◽  
Vol 74 (05) ◽  
pp. 1316-1322 ◽  
Author(s):  
Mary Ann McLane ◽  
Jagadeesh Gabbeta ◽  
A Koneti Rao ◽  
Lucia Beviglia ◽  
Robert A Lazarus ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Platelet Function ◽  
Sequence Similarity ◽  
Platelet Aggregation Inhibitors ◽  
Antiplatelet Drug ◽  
Rgd Sequence ◽  
Fibrinogen Receptor ◽  
Activated Platelets

SummaryNaturally-occurring fibrinogen receptor antagonists and platelet aggregation inhibitors that are found in snake venom (disintegrins) and leeches share many common features, including an RGD sequence, high cysteine content, and low molecular weight. There are, however, significant selectivity and potency differences. We compared the effect of three proteins on platelet function: albolabrin, a 7.5 kDa disintegrin, eristostatin, a 5.4 kDa disintegrin in which part of the disintegrin domain is deleted, and decorsin, a 4.5 kDa non-disintegrin derived from the leech Macrobdella decora, which has very little sequence similarity with either disintegrin. Decorsin was about two times less potent than albolabrin and six times less potent than eristostatin in inhibiting ADP- induced human platelet aggregation. It had a different pattern of interaction with glycoprotein IIb/IIIa as compared to the two disintegrins. Decorsin bound with a low affinity to resting platelets (409 nM) and to ADP-activated platelets (270 nM), and with high affinity to thrombin- activated platelets (74 nM). At concentrations up to 685 nM, it did not cause expression of a ligand-induced binding site epitope on the (β3 subunit of the GPIIb/IIIa complex. It did not significantly inhibit isolated GPIIb/IIIa binding to immobilized von Willebrand Factor. At low doses (1.5-3.0 μg/mouse), decorsin protected mice against death from pulmonary thromboembolism, showing an effect similar to eristostatin. This suggested that decorsin is a much more potent inhibitor of platelet aggregation in vivo than in vitro, and it may have potential as an antiplatelet drug.

SiRNA technology, the gene therapy of the future?

2008 ◽  
Vol 149 (4) ◽  
pp. 153-159 ◽  
Author(s):  
Zsuzsanna Rácz ◽  
Péter Hamar
Keyword(s):  
Gene Therapy ◽  
Short Interfering Rna ◽  
The Future ◽  
Interfering Rna

A genetikában új korszak kezdődött 17 éve, amikor a petúniában felfedezték a koszuppressziót. Később a koszuppressziót azonosították a növényekben és alacsonyabb rendű eukariótákban megfigyelt RNS-interferenciával (RNSi). Bár a növényekben ez ősi vírusellenes gazdaszervezeti védekezőmechanizmus, emlősökben az RNSi élettani szerepe még nincs teljesen tisztázva. Az RNSi-t rövid kettős szálú interferáló RNS-ek (short interfering RNA, siRNS) irányítják. A jelen cikkben összefoglaljuk az RNSi történetét és mechanizmusát, az siRNS-ek szerkezete és hatékonysága közötti összefüggéseket, a célsejtbe való bejuttatás virális és nem virális módjait. Az siRNS-ek klinikai alkalmazásának legfontosabb akadálya az in vivo alkalmazás. Bár a hidrodinamikus kezelés állatokban hatékony, embereknél nem alkalmazható. Lehetőséget jelent viszont a szervspecifikus katéterezés. A szintetizált siRNS-ek ismert mellékhatásait szintén tárgyaljuk. Bár a génterápia ezen új területén számos problémával kell szembenézni, a sikeres in vitro és in vivo kísérletek reményt jelentenek emberi betegségek siRNS-sel történő kezelésére.

Phytosomal Curcumin Elicits Anti-tumor Properties Through Suppression of Angiogenesis, Cell Proliferation and Induction of Oxidative Stress in Colorectal Cancer

2019 ◽  
Vol 24 (39) ◽  
pp. 4626-4638 ◽  
Author(s):  
Reyhaneh Moradi-Marjaneh ◽  
Seyed M. Hassanian ◽  
Farzad Rahmani ◽  
Seyed H. Aghaee-Bakhtiari ◽  
Amir Avan ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Colorectal Cancer ◽  
Therapeutic Potential ◽  
Vegf Signaling ◽  
Anticancer Effects ◽  
Inhibition Of Angiogenesis ◽  
Underlying Mechanisms ◽  
Apoptotic Activity

Background: Colorectal cancer (CRC) is one of the most common causes of cancer-associated mortality in the world. Anti-tumor effect of curcumin has been shown in different cancers; however, the therapeutic potential of novel phytosomal curcumin, as well as the underlying molecular mechanism in CRC, has not yet been explored. Methods: The anti-proliferative, anti-migratory and apoptotic activity of phytosomal curcumin in CT26 cells was assessed by MTT assay, wound healing assay and Flow cytometry, respectively. Phytosomal curcumin was also tested for its in-vivo activity in a xenograft mouse model of CRC. In addition, oxidant/antioxidant activity was examined by DCFH-DA assay in vitro, measurement of malondialdehyde (MDA), Thiol and superoxidedismutase (SOD) and catalase (CAT) activity and also evaluation of expression levels of Nrf2 and GCLM by qRT-PCR in tumor tissues. In addition, the effect of phytosomal curcumin on angiogenesis was assessed by the measurement of VEGF-A and VEGFR-1 and VEGF signaling regulatory microRNAs (miRNAs) in tumor tissue. Results: Phytosomal curcumin exerts anti-proliferative, anti-migratory and apoptotic activity in-vitro. It also decreases tumor growth and augmented 5-fluorouracil (5-FU) anti-tumor effect in-vivo. In addition, our data showed that induction of oxidative stress and inhibition of angiogenesis through modulation of VEGF signaling regulatory miRNAs might be underlying mechanisms by which phytosomal curcumin exerted its antitumor effect. Conclusion: Our data confirmed this notion that phytosomal curcumin administrates anticancer effects and can be used as a complementary treatment in clinical settings.

Novel Findings of Anti-cancer Property of Propofol

2018 ◽  
Vol 18 (2) ◽  
pp. 156-165 ◽  
Author(s):  
Jiaqiang Wang ◽  
Chien-shan Cheng ◽  
Yan Lu ◽  
Xiaowei Ding ◽  
Minmin Zhu ◽  
...  
Keyword(s):  
General Anesthesia ◽  
Cancer Progression ◽  
Molecular Mechanisms ◽  
Intravenous Anesthetic ◽  
The Past ◽  
Anti Cancer ◽  
Underlying Mechanisms ◽  
Recent Attention

Background: Propofol, a widely used intravenous anesthetic agent, is traditionally applied for sedation and general anesthesia. Explanation: Recent attention has been drawn to explore the effect and mechanisms of propofol against cancer progression in vitro and in vivo. Specifically, the proliferation-inhibiting and apoptosis-inducing properties of propofol in cancer have been studied. However, the underlying mechanisms remain unclear. Conclusion: This review focused on the findings within the past ten years and aimed to provide a general overview of propofol's malignance-modulating properties and the potential molecular mechanisms.

Studies on the mechanism of acute inhibition of thyroglobulin hydrolysis by iodine

1985 ◽  
Vol 108 (4) ◽  
pp. 511-517 ◽  
Author(s):  
Nandalal Bagchi ◽  
Birdie Shivers ◽  
Thomas R. Brown
Keyword(s):  
Time Course ◽  
Period 2 ◽  
Iodotyrosine Deiodinase ◽  
Rate Of Hydrolysis ◽  
Underlying Mechanisms ◽  
Excess Iodide ◽  
Sites Of Action ◽  
Hydrolysis Of

Abstract. Iodine in excess is known to acutely inhibit thyroidal secretion. In the present study we have characterized the time course of the iodine effect in vitro and investigated the underlying mechanisms. Labelled thyroid glands were cultured in vitro in medium containing mononitrotyrosine, an inhibitor of iodotyrosine deiodinase. The rate of hydrolysis of labelled thyroglobulin was measured as the proportion of labelled iodotyrosines and iodothyronines recovered at the end of culture and was used as an index of thyroidal secretion. Thyrotrophin (TSH) administered in vivo acutely stimulated the rate of thyroglobulin hydrolysis. Addition of Nal to the culture medium acutely inhibited both basal and TSH-stimulated thyroglobulin hydrolysis. The effect of iodide was demonstrable after 2 h, maximal after 6 h and was not reversible upon removal of iodide. Iodide abolished the dibutyryl cAMP induced stimulation of thyroglobulin hydrolysis. Iodide required organic binding of iodine for its effect but new protein or RNA synthesis was not necessary. The inhibitory effects of iodide and lysosomotrophic agents such as NH4C1 and chloroquin on thyroglobulin hydrolysis were additive suggesting different sites of action. Iodide added in vitro altered the distribution of label in prelabelled thyroglobulin in a way that suggested increased coupling in the thyroglobulin molecule. These data indicate that 1) the iodide effect occurs progressively over a 6 h period, 2) continued presence of iodide is not necessary once the inhibition is established, 3) iodide exerts its action primarily at a post cAMP, prelysosomal site and 4) the effect requires organic binding of iodine, but not new RNA or protein synthesis. Our data are consistent with the hypothesis that excess iodide acutely inhibits thyroglobulin hydrolysis by increasing the resistance of thyroglobulin to proteolytic degradation through increased iodination and coupling.

scholarly journals USP9X-mediated KDM4C deubiquitination promotes lung cancer radioresistance by epigenetically inducing TGF-β2 transcription

2021 ◽  
Author(s):  
Xiaohua Jie ◽  
William Pat Fong ◽  
Rui Zhou ◽  
Ye Zhao ◽  
Yingchao Zhao ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Affinity Purification ◽  
Smad Signaling ◽  
Lung Cancer Patients ◽  
Lysine Specific Demethylase ◽  
Underlying Mechanisms ◽  
H3k9me3 Level ◽  
Critical Binding

AbstractRadioresistance is regarded as the main barrier to effective radiotherapy in lung cancer. However, the underlying mechanisms of radioresistance remain elusive. Here, we show that lysine-specific demethylase 4C (KDM4C) is overexpressed and correlated with poor prognosis in lung cancer patients. We provide evidence that genetical or pharmacological inhibition of KDM4C impairs tumorigenesis and radioresistance in lung cancer in vitro and in vivo. Moreover, we uncover that KDM4C upregulates TGF-β2 expression by directly reducing H3K9me3 level at the TGF-β2 promoter and then activates Smad/ATM/Chk2 signaling to confer radioresistance in lung cancer. Using tandem affinity purification technology, we further identify deubiquitinase USP9X as a critical binding partner that deubiquitinates and stabilizes KDM4C. More importantly, depletion of USP9X impairs TGF-β2/Smad signaling and radioresistance by destabilizing KDM4C in lung cancer cells. Thus, our findings demonstrate that USP9X-mediated KDM4C deubiquitination activates TGF-β2/Smad signaling to promote radioresistance, suggesting that targeting KDM4C may be a promising radiosensitization strategy in the treatment of lung cancer.

scholarly journals Molecular and Cellular Mechanisms of Metformin in Cervical Cancer

Cancers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2545
Author(s):  
Ya-Hui Chen ◽  
Po-Hui Wang ◽  
Pei-Ni Chen ◽  
Shun-Fa Yang ◽  
Yi-Hsuan Hsiao
Keyword(s):  
Cervical Cancer ◽  
Potential Role ◽  
Treatment Options ◽  
Cellular Mechanisms ◽  
Anticancer Effects ◽  
Clinical Benefits ◽  
Underlying Mechanisms

Cervical cancer is one of the major gynecologic malignancies worldwide. Treatment options include chemotherapy, surgical resection, radiotherapy, or a combination of these treatments; however, relapse and recurrence may occur, and the outcome may not be favorable. Metformin is an established, safe, well-tolerated drug used in the treatment of type 2 diabetes; it can be safely combined with other antidiabetic agents. Diabetes, possibly associated with an increased site-specific cancer risk, may relate to the progression or initiation of specific types of cancer. The potential effects of metformin in terms of cancer prevention and therapy have been widely studied, and a number of studies have indicated its potential role in cancer treatment. The most frequently proposed mechanism underlying the diabetes–cancer association is insulin resistance, which leads to secondary hyperinsulinemia; furthermore, insulin may exert mitogenic effects through the insulin-like growth factor 1 (IGF-1) receptor, and hyperglycemia may worsen carcinogenesis through the induction of oxidative stress. Evidence has suggested clinical benefits of metformin in the treatment of gynecologic cancers. Combining current anticancer drugs with metformin may increase their efficacy and diminish adverse drug reactions. Accumulating evidence is indicating that metformin exerts anticancer effects alone or in combination with other agents in cervical cancer in vitro and in vivo. Metformin might thus serve as an adjunct therapeutic agent for cervical cancer. Here, we reviewed the potential anticancer effects of metformin against cervical cancer and discussed possible underlying mechanisms.

scholarly journals CircFAM13B promotes the proliferation of hepatocellular carcinoma by sponging miR-212, upregulating E2F5 expression and activating the P53 pathway

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ying Xie ◽  
Xiaofeng Hang ◽  
Wensheng Xu ◽  
Jing Gu ◽  
Yuanjing Zhang ◽  
...  
Keyword(s):  
Gene Expression ◽  
Hepatocellular Carcinoma ◽  
Gene Expression Omnibus ◽  
Differentially Expressed ◽  
In Vivo Studies ◽  
Circular Rnas ◽  
Novel Target ◽  
Underlying Mechanisms

Abstract Background Most of the biological functions of circular RNAs (circRNAs) and the potential underlying mechanisms in hepatocellular carcinoma (HCC) have not yet been discovered. Methods In this study, using circRNA expression data from HCC tumor tissues and adjacent tissues from the Gene Expression Omnibus database, we identified out differentially expressed circRNAs and verified them by qRT-PCT. Functional experiments were performed to evaluate the effects of circFAM13B in HCC in vitro and in vivo. Results We found that circFAM13B was the most significantly differentially expressed circRNA in HCC tissue. Subsequently, in vitro and in vivo studies also demonstrated that circFAM13B promoted the proliferation of HCC. Further studies revealed that circFAM13B, a sponge of miR-212, is involved in the regulation of E2F5 gene expression by competitively binding to miR-212, inhibits the activation of the P53 signalling pathway, and promotes the proliferation of HCC cells. Conclusions Our findings revealed the mechanism underlying the regulatory role played by circFAM13B, miR-212 and E2F5 in HCC. This study provides a new theoretical basis and novel target for the clinical prevention and treatment of HCC.

scholarly journals YAP1 overexpression contributes to the development of enzalutamide resistance by induction of cancer stemness and lipid metabolism in prostate cancer

Oncogene ◽  
2021 ◽  
Author(s):  
Hsiu-Chi Lee ◽  
Chien-Hui Ou ◽  
Yun-Chen Huang ◽  
Pei-Chi Hou ◽  
Chad J. Creighton ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Lipid Metabolism ◽  
Critical Issue ◽  
Castration Resistant Prostate Cancer ◽  
Cancer Stemness ◽  
New Treatment ◽  
Underlying Mechanisms ◽  
Transcriptional Complex

AbstractMetastatic castration-resistant prostate cancer (mCRPC) is a malignant and lethal disease caused by relapse after androgen-deprivation (ADT) therapy. Since enzalutamide is innovated and approved by US FDA as a new treatment option for mCRPC patients, drug resistance for enzalutamide is a critical issue during clinical usage. Although several underlying mechanisms causing enzalutamide resistance were previously identified, most of them revealed that drug resistant cells are still highly addicted to androgen and AR functions. Due to the numerous physical functions of AR in men, innovated AR-independent therapy might alleviate enzalutamide resistance and prevent production of adverse side effects. Here, we have identified that yes-associated protein 1 (YAP1) is overexpressed in enzalutamide-resistant (EnzaR) cells. Furthermore, enzalutamide-induced YAP1 expression is mediated through the function of chicken ovalbumin upstream promoter transcription factor 2 (COUP-TFII) at the transcriptional and the post-transcriptional levels. Functional analyses reveal that YAP1 positively regulates numerous genes related to cancer stemness and lipid metabolism and interacts with COUP-TFII to form a transcriptional complex. More importantly, YAP1 inhibitor attenuates the growth and cancer stemness of EnzaR cells in vitro and in vivo. Finally, YAP1, COUP-TFII, and miR-21 are detected in the extracellular vesicles (EVs) isolated from EnzaR cells and sera of patients. In addition, treatment with EnzaR-EVs induces the abilities of cancer stemness, lipid metabolism and enzalutamide resistance in its parental cells. Taken together, these results suggest that YAP1 might be a crucial factor involved in the development of enzalutamide resistance and can be an alternative therapeutic target in prostate cancer.

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