当前位置: 首页 >> 检索结果
共有 7354 条符合本次的查询结果, 用时 2.2014408 秒

7041. Targeting abundant survivin expression in liposarcoma: subtype dependent therapy responses to YM155 treatment.

作者: Christian Vay.;Philipp M Schlünder.;Levent Dizdar.;Irene Esposito.;Markus P H Ghadimi.;Wolfram T Knoefel.;Andreas Krieg.
来源: J Cancer Res Clin Oncol. 2022年148卷3期633-645页
Liposarcoma (LPS) represent the largest group of malignant soft tissue tumours comprising a heterogeneous group of subtypes in which the degrees of chemoresistance and radiosensitivity strongly vary. Consequently, it is of utmost interest to establish novel therapeutic regimens based on molecular targets.

7042. Methyl p‑hydroxycinnamate exerts anti‑inflammatory effects in mouse models of lipopolysaccharide‑induced ARDS.

作者: Seong-Man Kim.;Jae-Hong Min.;Jung Hee Kim.;Jinseon Choi.;Jin-Mi Park.;Juhyun Lee.;Soo Hyeon Goo.;Jae Hoon Oh.;Seung-Ho Kim.;Wanjoo Chun.;Kyung-Seop Ahn.;Sukmo Kang.;Jae-Won Lee.
来源: Mol Med Rep. 2022年25卷1期
Methyl p‑hydroxycinnamate (MH), an esterified derivative of p‑Coumaric acid exerts anti‑inflammatory effects on lipopolysaccharide (LPS)‑stimulated RAW264.7 macrophages. Based on these effects, the present study investigated the protective role of MH in a mouse model of LPS‑induced acute respiratory distress syndrome (ARDS). The results demonstrated that administration of LPS (5 mg/kg intranasally) markedly increased the neutrophil/macrophage numbers and levels of inflammatory molecules (TNF‑α, IL‑6, IL‑1β and reactive oxygen species) in the bronchoalveolar lavage fluid (BALF) of mice. On histological examination, the presence of inflammatory cells was observed in the lungs of mice administered LPS. LPS also notably upregulated the secretion of monocyte chemoattractant protein‑1 and protein content in BALF as well as expression of inducible nitric oxide synthase in the lungs of mice; it also caused activation of p38 mitogen‑activated protein kinase (MAPK) and NF‑κB signaling. However, MH treatment significantly suppressed LPS‑induced upregulation of inflammatory cell recruitment, inflammatory molecule levels and p38MAPK/NF‑κB activation, and also led to upregulation of heme oxygenase‑1 (HO‑1) expression in the lungs of mice. In addition, the ability of MH to induce HO‑1 expression was confirmed in RAW264.7 macrophages. Taken together, the findings of the present study indicated that MH may exert protective effects against airway inflammation in ARDS mice by inhibiting inflammatory cell recruitment and the production of inflammatory molecules.

7043. Propofol induces apoptosis and ameliorates 5‑fluorouracil resistance in OSCC cells by reducing the expression and secretion of amphiregulin.

作者: Kung-Ssu Yang.;Pi-Cheng Che.;Ming-Ju Hsieh.;I-Neng Lee.;Yu-Ping Wu.;Ming-Shan Chen.;Jui-Chieh Chen.
来源: Mol Med Rep. 2022年25卷1期
Among the different types of oral cancer, >90% of cases are oral squamous cell carcinoma (OSCC). 5‑fluorouracil (5‑FU) is a commonly used treatment for OSCC, but cells typically display resistance to the drug. Propofol, an intravenous anesthetic agent, exhibits certain anticancer effects, including the inhibition of cancer cell proliferation, migration and invasion. Secreted proteins, such as growth factors and cytokines are involved in cancer development and progression, but the effect of propofol on secreted proteins in OSCC is not completely understood. An MTT assay, flow cytometry and western blotting were performed to determine the anticancer effects of propofol. The secretion profile of OSCC was determined using an antibody array, and clinical importance was assessed using the Gene Expression Profiling Interactive Analysis database. The results were verified by performing reverse transcription‑quantitative PCR (RT‑qPCR) and western blotting. 5‑FU‑resistant cells were established to determine the role of the gene of interest in drug resistance. The results demonstrated that propofol decreased cell viability and promoted cell apoptosis. The antibody array results showed that propofol attenuated the secretion of multiple growth factors. The bioinformatics results indicated that amphiregulin (AREG) was expressed at significantly higher levels in cancer tissues, which was also related to poor prognosis. The results of RT‑qPCR and western blotting revealed that propofol decreased AREG expression. Pretreatment with exogenous recombinant AREG increased EGFR activation and conferred propofol resistance. Moreover, the results indicated that the expression and activation of AREG was also related to 5‑FU resistance, but propofol ameliorated 5‑FU drug resistance. Therefore, the present study suggested that propofol combination therapy may serve as an effective treatment strategy for OSCC.

7044. Cyclometalated Ru(II)-isoquinoline complexes overcome cisplatin resistance of A549/DDP cells by downregulation of Nrf2 via Akt/GSK-3β/Fyn pathway.

作者: Lanmei Chen.;Jie Wang.;Xianhong Cai.;Suxiang Chen.;Jingjing Zhang.;Baojun Li.;Weigang Chen.;Xinhua Guo.;Hui Luo.;Jincan Chen.
来源: Bioorg Chem. 2022年119卷105516页
Both ruthenium (Ru) and isoquinoline (IQ) compounds are regarded as potential anticancer drug candidates. Here, we report the synthesis and characterization of three novel cyclometalated Ru(II)-isoquinoline complexes: RuIQ-3, RuIQ-4, and RuIQ-5, and evaluation of their in vitro cytotoxicities against a panel of cell lines including A549/DDP, a cisplatin-resistant human lung cancer cell line. A549/DDP 3D multicellular tumor spheroids (MCTSs) were also used to detect the drug resistance reversal effect of Ru(II)-IQ complexes. Our results indicated that the cytotoxic activities against cancer cells of Ru(II)-IQ complexes, especially RuIQ-5, were superior compared with cisplatin. In addition, RuIQ-5 exhibited low toxicity towards both normal HBE cells in vitro and zebrafish embryos in vivo. Further investigation on cellular mechanism of action indicated that after absorption by A549/DDP cells, RuIQ-5 was mainly distributed in the nucleus, which is different from cisplatin. Besides, RuIQ-5 could induce apoptosis through mitochondrial dysfunction, reactive oxygen species (ROS) accumulation, ROS-mediated DNA damage, and cycle arrest at both S and G2/M phases. Moreover, RuIQ-5 could inhibit the overexpression of Nrf2 through regulation of Akt/GSK-3β/Fyn signaling pathway and hindering the nuclear translocation of Nrf2. Based on these findings, we firmly believe that the studied Ru(II)-IQ complexes hold great promise as anticancer therapeutics with high effectiveness and low toxicity.

7045. Multifaceted epigenetic regulation of porcine testicular aromatase.

作者: Trish Berger.;Jens Vanselow.;Alan Conley.;Tana Jo Almand.;Barbara S Nitta-Oda.
来源: Mol Cell Endocrinol. 2022年541卷111526页
Testicular aromatase catalyzes the synthesis of estradiol, which contributes to regulation of porcine Sertoli cell proliferation and postpubertal maintenance of Sertoli cell numbers. Although aromatase enzymatic activity decreases with age and is persistently reprogrammed by prepubertal treatment with the aromatase inhibitor letrozole, the molecular bases for regulation have not been identified. DNA methylation was examined as a potential regulatory mechanism using DNA from Leydig cells isolated from 16-, 40-, and 68-week-old boars and from 68- week-old littermates treated with the aromatase inhibitor, letrozole. Methylation levels of individual CpG dinucleotides located in the distal untranslated exon 1 of the relevant aromatase encoding gene, CYP19A3, were quite high in Leydig cell DNA, and increased further with maturity of boar (P < 0.05), while aromatase activity and transcript abundance decreased more than two-fold. However, reduced aromatase activity following letrozole treatment was not accompanied by altered DNA methylation. Testicular expression of miR378 was altered by prepubertal treatment with letrozole. The data provide evidence for two different epigenetic mechanisms that regulate aromatase expression and enzymatic activity in the boar testis.

7046. A natural product, voacamine, sensitizes paclitaxel-resistant human ovarian cancer cells.

作者: Evelin Pellegrini.;Giuseppina Multari.;Francesca Romana Gallo.;Davide Vecchiotti.;Francesca Zazzeroni.;Maria Condello.;Stefania Meschini.
来源: Toxicol Appl Pharmacol. 2022年434卷115816页
Most women with ovarian cancer are treated with chemotherapy before or after surgery. Unfortunately, chemotherapy treatment can cause negative side effects and the onset of multidrug resistance (MDR). The aim of this study is to evaluate the chemosensitizing effect of a natural compound, voacamine (VOA), in ovarian (A2780 DX) and colon (LoVo DX) cancer drug-resistant cell lines which overexpress P-glycoprotein (P-gp), in combination with paclitaxel (PTX), or doxorubicin (DOX) or 5-fluorouracil (5-FU). VOA, a bisindole alkaloid extracted from Peschiera fuchsiaefolia, has already been shown to be effective in enhancing the effect of doxorubicin, because it interferes with the P-gp function. Ovarian cancer cytotoxicity test shows that single treatments with VOA, DOX and PTX do not modify cell viability, while pretreatment with VOA, and then PTX or DOX for 72 h, induces a decrease. In colon cancer, since 5-FU is not a-substrate for P-gp, VOA has no sensitizing effect while in VOA + DOX there is a decrease in viability. Annexin V/PI test, cell cycle analysis, activation of cleaved PARP1 confirm that VOA plus PTX induce apoptotic cell death. Confocal microscopy observations show the different localization of NF-kB after treatment with VOA + PTX, confirming the inhibition of nuclear translocation induced by VOA pretreatment. Our data show the specific effect of VOA which only works on drugs known to be substrates of P-gp.

7047. Interferon-induced transmembrane protein 2 promotes epithelial-mesenchymal transition by activating transforming growth factor-β1/small mother against decapentaplegic 2 signaling in gastric cancer.

作者: Yonggang Liu.;Minyu Zhou.;Jianhua Wu.;Zhaowei Wen.;Yisheng Fang.;Li Lin.;Meihua Luo.;Li Sun.;Wangjun Liao.
来源: Mol Biol Rep. 2022年49卷2期997-1006页
Gastric cancer (GC) is one of the most prevalent malignancy around the world. Primary tumor cells are enabled to invade and migrate into adjacent normal tissues to form secondary tumors. Epithelial-mesenchymal transitions (EMT) plays a pivotal role in facilitating tumor progression. Abundant evidence suggested that the transforming growth factor-β1 (TGF-β1) triggered the process of EMT. Nonetheless, the precise molecular mechanisms underlying EMT requires further elucidation, and there still lacks effective specific therapeutic target. In our recent research, we demonstrated that the interferon (IFN)-induced transmembrane protein 2 (IFITM2) promoted the growth and metastasis of GC. However, it remains unclear whether IFITM2 involves in TGF-β1 mediated EMT in GC.

7048. Investigating histidinylated highly branched poly(lysine) for siRNA delivery.

作者: Ali Alazzo.;Nurcan Gumus.;Pratik Gurnani.;Snjezana Stolnik.;Ruman Rahman.;Keith Spriggs.;Cameron Alexander.
来源: J Mater Chem B. 2022年10卷2期236-246页
The temporary silencing of disease-associated genes utilising short interfering RNA (siRNA) is a potent and selective route for addressing a wide range of life limiting disorders. However, the few clinically approved siRNA therapies rely on lipid based formulations, which although potent, provide limited chemical space to tune the stability, efficacy and tissue selectivity. In this study, we investigated the role of molar mass and histidinylation for poly(lysine) based non-viral vectors, synthesised through a fully aqueous thermal condensation polymerisation. Formulation and in vitro studies revealed that higher molar mass derivatives yielded smaller polyplexes attributed to a greater affinity for siRNA at lower N/P ratios yielding greater transfection efficiency, albeit with some cytotoxicity. Histidinylation had a negligible effect on formulation size, yet imparted a moderate improvement in biocompatibility, but did not provide any meaningful improvement over silencing efficiency compared to non-histidinylated derivatives. This was attributed to a greater degree of cellular internalisation for non-histidinylated analogues, which was enhanced with the higher molar mass material.

7049. Promising Therapeutic Targets in Kidney Renal Clear Cell Carcinoma: PLXNA1 and PLXNB3.

作者: Can-Xuan Li.;Dan Long.;Quan Meng.
来源: Cancer Biother Radiopharm. 2024年39卷4期276-290页
Aims: This study sets out to identify dysregulated plexins and investigate their roles in KIRC through an integrated bioinformatics approach. Methods: RNA-sequencing data and clinicopathological information of KIRC, extracted from The Cancer Genome Atlas (TCGA) database, were used to perform comprehensive bioinformatics analysis. Results: Almost all plexin gene family members were dysregulated in KIRC. Univariate and multivariate Cox regression analyses revealed that PLXNA1/B3 were independent prognostic factors of overall survival in patients with KIRC. Mechanically, PLXNA1/B3 may promote ccRCC progression through several cancer-related signaling pathways, tumor immunity, and angiogenesis. Drug sensitivity analysis suggested that vemurafenib was the potential drug for PLXNA1/B3. Conclusion: Herein, we found that PLXNA1/B3 were independent prognostic factors, making them attractive new targets for KIRC treatment.

7050. Mouse lung organoid responses to reduced, increased, and cyclic stretch.

作者: Rashika Joshi.;Matthew R Batie.;Qiang Fan.;Brian M Varisco.
来源: Am J Physiol Lung Cell Mol Physiol. 2022年322卷1期L162-L173页
Most lung development occurs in the context of cyclic stretch. Alteration of the mechanical microenvironment is a common feature of many pulmonary diseases, with congenital diaphragmatic hernia (CDH) and fetal tracheal occlusion (FETO, a therapy for CDH) being extreme examples with changes in lung structure, cell differentiation, and function. To address limitations in cell culture and in vivo mechanotransductive models, we developed two mouse lung organoid (mLO) mechanotransductive models using postnatal day 5 (PND5) mouse lung CD326-positive cells and fibroblasts subjected to increased, decreased, and cyclic strain. In the first model, mLOs were exposed to forskolin (FSK) and/or disrupted (DIS) and evaluated at 20 h. mLO cross-sectional area changed by +59%, +24%, and -68% in FSK, control, and DIS mLOs, respectively. FSK-treated organoids had twice as many proliferating cells as other organoids. In the second model, 20 h of 10.25% biaxial cyclic strain increased the mRNAs of lung mesenchymal cell lineages compared with static stretch and no stretch. Cyclic stretch increased TGF-β and integrin-mediated signaling, with upstream analysis indicating roles for histone deacetylases, microRNAs, and long noncoding RNAs. Cyclic stretch mLOs increased αSMA-positive and αSMA-PDGFRα-double-positive cells compared with no stretch and static stretch mLOs. In this PND5 mLO mechanotransductive model, cell proliferation is increased by static stretch, and cyclic stretch induces mesenchymal gene expression changes important in postnatal lung development.

7051. Corilagin induces apoptosis and inhibits autophagy of HL‑60 cells by regulating miR‑451/HMGB1 axis.

作者: Shu Jia.;Dongye He.;Xiao Liang.;Panpan Cheng.;Jilan Liu.;Mingtai Chen.;Cuiling Wang.;Hao Zhang.;Chunyang Meng.
来源: Mol Med Rep. 2022年25卷1期
Corilagin is the primary active component of the Euphorbia phyllanthus plant and has significant anti‑cancer properties. However, the biological effects and mechanisms of corilagin on acute myeloid leukemia (AML) have not been clarified. The Cell Counting Kit‑8 and Carboxyfluorescein Diacetate Succinimidyl Ester assay results showed that corilagin significantly inhibited proliferation of the AML cell line HL‑60 in a time‑ and dose‑dependent manner. Western blotting and flow cytometry analysis were performed to determine the levels of apoptosis in HL‑60 cells. The protein levels of cleaved caspase‑3 and Bak were upregulated, while Bcl‑xl was downregulated in cells treated with corilagin. The percentage of early‑ and late‑stage apoptotic cells increased following corilagin treatment in a dose‑dependent manner, indicating that the intrinsic mitochondrial apoptosis pathway was activated by corilagin. Simultaneously, western blotting and immunofluorescence results revealed that autophagy was suppressed; this was accompanied by a decrease in light chain 3‑II (LC3‑II) conversion and autophagosomes. MicroRNA (miRNA/miR) profile analysis showed that corilagin elevated the expression of the tumor suppressor miR‑451, while the mRNA and protein levels of high mobility group protein B1 (HMGB1), the target of miR‑451, decreased following exposure to corilagin. Knockdown of miR‑451 decreased the downregulation of HMGB1 caused by corilagin, indicating negative regulation of HMGB1 by miR‑451 during corilagin treatment. Furthermore, knockdown of miR‑451 also attenuated corilagin‑induced proliferation inhibition of HL‑60 cells, implying that miR‑451 was essential for the proliferation inhibitory effect of corilagin. In conclusion, these results indicated that corilagin induced apoptosis and inhibited autophagy in HL‑60 cells by regulating the miR‑451/HMGB1 axis, and corilagin may be a novel therapeutic drug for the treatment of AML.

7052. Crocetin ameliorates non-alcoholic fatty liver disease by modulating mitochondrial dysfunction in L02 cells and zebrafish model.

作者: Zijin Xu.;Susu Lin.;Zheren Tong.;Suhong Chen.;Yifeng Cao.;Qiaoqiao Li.;Yuli Jiang.;Weijie Cai.;Yingpeng Tong.;Bathaie S Zahra.;Ping Wang.
来源: J Ethnopharmacol. 2022年285卷114873页
Traditional Chinese medicine considers that the etiology and pathogenesis of non-alcoholic fatty liver disease (NAFLD) are related to liver depression and qi stagnation. Saffron and its active ingredient, crocetin (CCT), are used for the treatment of metabolic diseases owing to their "Liver deobstruent" and "Liver tonic" effects. However, the effect of CCT on NAFLD has not been fully elucidated. In the present study, the effect and potential molecular mechanism of CCT were explored in both in vivo and in vitro models of NAFLD.

7053. Beneficial effects of mijianchangpu decoction on ischemic stroke through components accessing to the brain based on network pharmacology.

作者: Xiaojun Zhao.;Jingjing Liu.;Lingling Yang.;Yang Niu.;Ruru Ren.;Chao Su.;Yingli Wang.;Jianyu Chen.;Xueqin Ma.
来源: J Ethnopharmacol. 2022年285卷114882页
To explore the effective components, potential targets and neuroprotective related mechanisms of Mijianchangpu decoction (MJCPD), a well-known TCM used by the Chinese Hui minorities to treat stroke, on the prevention and treatment of ischemic stroke (IS) by using experimental models combined with network pharmacology.

7054. Comparative study of estrogenic activities of phytoestrogens using OECD in vitro and in vivo testing methods.

作者: Kyu Sang Sim.;Song Park.;Huiwon Seo.;Seok-Hee Lee.;Hee-Seok Lee.;Yooheon Park.;Jun Ho Kim.
来源: Toxicol Appl Pharmacol. 2022年434卷115815页
With growing scientific interest in phytoestrogens, a number of studies have investigated the estrogenic potential of phytoestrogens in a wide variety of assay systems. However, evaluations of individual phytoestrogens with different assay systems make it difficult for predicting their relative estrogenic potency. The objective of this study was to compare estrogenic properties of fifteen known phytoestrogens using an estrogen receptor-α (ER-α) dimerization assay and Organization for Economic Cooperation and Development (OECD) standardized methods including in vitro estrogen receptor (ER) transactivation assay using VM7Luc4E2 cells and in vivo uterotrophic assay using an immature rat model. Human ER-α dimerization assay showed positive responses of eight test compounds and negative responses of seven compounds. These results were consistently found in luciferase reporter assay results for evaluating ER transactivation ability. Seven test compounds exhibiting relatively higher in vitro estrogenic activities were subjected to uterotrophic bioassays. Significant increases in uterine weights were only found after treatments with biochanin A, 8-prenylnaringenin, and coumestrol. Importantly, their uterotrophic effects were lost when animals were co-treated with antagonist of ER, indicating their ER-dependent effects in the uterus. In addition, analysis of estrogen responsive genes revealed that these phytoestrogens regulated uterine gene expressions differently compared to estrogens. Test methods used in this study provided a high consistency between in vitro and in vivo results. Thus, they could be used as effective screening tools for phytoestrogens, particularly focusing on their interactions with ER-α.

7055. Antidiabetic potential of soy protein/peptide: A therapeutic insight.

作者: Dibyendu Das.;Mir Ekbal Kabir.;Sanjib Sarkar.;Sawlang Borsingh Wann.;Jatin Kalita.;Prasenjit Manna.
来源: Int J Biol Macromol. 2022年194卷276-288页
Soybean (Glycine max) harbours high quality proteins which have been evident to exhibit therapeutic properties in alleviating many diseases including but not limited to diabetes and its related metabolic complications. Since diabetes is often manifested with hyperglycemia, impaired energy homeostasis and even low-grade chronic inflammation, plenty of information has raised the suggestion for soy protein supplementation in preventing and controlling these abnormalities. Moreover, clinical intervention studies have established a noteworthy correlation between soy protein intake and lower prevalence of diabetes. Besides soy protein, various soy-derived peptides also have been found to trigger antidiabetic response in different in vitro and in vivo models. Molecular mechanisms underlying the antidiabetic actions of soy protein and peptide have been predicted in many literatures. Results demonstrate that components of soy protein can act in diversified ways and modulate various cell signaling pathways to bring energy homeostasis and to regulate inflammatory parameters associated with diabetic pathophysiology. The main objective of the present review lies in a systemic understanding of antidiabetic role of soy protein and peptide in the context of impaired glucose and lipid metabolism, and inflammation.

7056. A heat shock protein 90 inhibitor reduces oncoprotein expression and induces cell death in heterogeneous glioblastoma cells with EGFR, PDGFRA, CDK4, and NF1 aberrations.

作者: Kuan-Ta Ho.;Pei-Fan Chen.;Jian-Ying Chuang.;Po-Wu Gean.;Yuan-Shuo Hsueh.
来源: Life Sci. 2022年288卷120176页
Glioblastoma (GBM) is a highly malignant brain tumor. After treatment with the first-line drug temozolomide, only 50% of patients are responsive. Recent literature shows that the difficulty in treating GBM is mainly due to the heterogeneity of its four major cellular states, which are characterized by differences in EGFR, PDGFRA, CDK4, and NF1. Therefore, development of a multitarget drug is a potential strategy for treating heterogeneous GBM.

7057. Dihydroartemisinin represses oral squamous cell carcinoma progression through downregulating mitochondrial calcium uniporter.

作者: Shen Zheng.;Ran Wu.;Yunlong Deng.;Qiang Zhang.
来源: Bioengineered. 2022年13卷1期227-241页
Dysregulation of mitochondrial calcium uniporter (MCU) exerts a carcinogenic effect in several cancers. Nevertheless, the roles of MCU in oral squamous cell carcinoma (OSCC) remain elusive. It has been reported that dihydroartemisinin (DHA) may suppress the progression of OSCC but its associated mechanisms have not been investigated. The purpose of our research was to observe the biological function of MCU on OSCC and its regulatory relationship with DHA. MCU, MICU1, MICU2, N-cadherin, TGF-β and vimentin expression was detected in OSCC and peritumoral tissues by immunohistochemistry and Western blot. Following DHA treatment, the expression of the aforementioned proteins was detected in CAL-27 cells transfected with shMCU or pcDNA3.1-MCU by Western blot or immunofluorescence. Furthermore, clone formation, mitochondrial membrane potential (MMP), wound healing and transwell assays were presented in CAL-27 cells treated with DHA, shMCU or pcDNA3.1-MCU. Our results showed that the members of MCU complex (MCU, MICU1 and MICU2) were overexpressed in OSCC than peritumoral tissues. Furthermore, TGF-β and epithelial to mesenchymal transition (EMT) proteins (N-cadherin and vimentin) exhibited higher expression in OSCC. DHA treatment significantly lowered the expression of MCU in CAL-27 cells. MCU overexpression reversed the inhibitory effects of DHA on MICU1, MICU2, N-cadherin, TGF-β and vimentin. MCU knockdown or DHA suppressed proliferation, MMP and migration of CAL-27 cells. DHA treatment could reverse the effects of MCU overexpression. Collectively, our study demonstrated that MCU was an oncogene of OSCC and DHA exerted a suppressive role on proliferation and migration of OSCC cells by suppressing MCU expression.

7058. β3-Adrenergic receptor downregulation leads to adipocyte catecholamine resistance in obesity.

作者: Joseph M Valentine.;Maryam Ahmadian.;Omer Keinan.;Mohammad Abu-Odeh.;Peng Zhao.;Xin Zhou.;Mark P Keller.;Hui Gao.;Ruth T Yu.;Christopher Liddle.;Michael Downes.;Jin Zhang.;Aldons J Lusis.;Alan D Attie.;Ronald M Evans.;Mikael Rydén.;Alan R Saltiel.
来源: J Clin Invest. 2022年132卷2期
The dysregulation of energy homeostasis in obesity involves multihormone resistance. Although leptin and insulin resistance have been well characterized, catecholamine resistance remains largely unexplored. Murine β3-adrenergic receptor expression in adipocytes is orders of magnitude higher compared with that of other isoforms. While resistant to classical desensitization pathways, its mRNA (Adrb3) and protein expression are dramatically downregulated after ligand exposure (homologous desensitization). β3-Adrenergic receptor downregulation also occurs after high-fat diet feeding, concurrent with catecholamine resistance and elevated inflammation. This downregulation is recapitulated in vitro by TNF-α treatment (heterologous desensitization). Both homologous and heterologous desensitization of Adrb3 were triggered by induction of the pseudokinase TRIB1 downstream of the EPAC/RAP2A/PI-PLC pathway. TRIB1 in turn degraded the primary transcriptional activator of Adrb3, CEBPα. EPAC/RAP inhibition enhanced catecholamine-stimulated lipolysis and energy expenditure in obese mice. Moreover, adipose tissue expression of genes in this pathway correlated with body weight extremes in a cohort of genetically diverse mice and with BMI in 2 independent cohorts of humans. These data implicate a signaling axis that may explain reduced hormone-stimulated lipolysis in obesity and resistance to therapeutic interventions with β3-adrenergic receptor agonists.

7059. Elevated expression of RIT1 hyperactivates RAS/MAPK signal and sensitizes hepatocellular carcinoma to combined treatment with sorafenib and AKT inhibitor.

作者: Liangzhan Sun.;Shaoyan Xi.;Zhengdong Zhou.;Feifei Zhang.;Pengchao Hu.;Yuzhu Cui.;Shasha Wu.;Ying Wang.;Shayi Wu.;Yanchen Wang.;Yuyang Du.;Jingyi Zheng.;Hui Yang.;Miao Chen.;Qian Yan.;Dandan Yu.;Chaoran Shi.;Yu Zhang.;Dan Xie.;Xin-Yuan Guan.;Yan Li.
来源: Oncogene. 2022年41卷5期732-744页
Hyperactivation of RAS/MAPK signaling is commonly observed in hepatocellular carcinoma (HCC). Gain-of-function mutations of canonical RAS genes, however, are rarely detected and it remains unclear how the activity of this pathway is turned on during hepatocarcinogenesis. We performed a comprehensive analysis of RAS superfamily genetic alterations across ten subfamilies, 152 members in 377 HCC patients from the Cancer Genome Atlas database. RIT1 (Ras-like without CAAX 1) was the most frequently altered RAS member amplified in 13% of the HCC cohort. Both genomic amplification and CREB-mediated transcriptional activation contributed to the elevated RIT1 expression, and its overexpression correlated with RAS/MAPK activation and poor prognosis. Then, we found that RIT1-induced angiogenesis via the MEK/ERK/EIF4E/HIF1-α/VEGFA axis. MAP3K11 and MAP3K12, in addition to CRAF, could mediate this process by binding to RIT1. Moreover, RIT1 increased the phosphorylation of p38 MAPK and AKT to promote cell survival under reactive oxygen species stress. Based on this mechanistic understanding, we treated RIT1-overexpressing HCC with combined regimen sorafenib plus AKT inhibitor, and achieved enhanced antitumor effects in vivo. Our study reveals RAS "orphan" member RIT1 as the most common genetic alteration of RAS family in HCC and combination of sorafenib with AKT inhibitor might be a promising treatment strategy for RIT1-overexpressing HCC.

7060. Thymidylate synthase O-GlcNAcylation: a molecular mechanism of 5-FU sensitization in colorectal cancer.

作者: Ninon Very.;Stéphan Hardivillé.;Amélie Decourcelle.;Julien Thévenet.;Madjid Djouina.;Adeline Page.;Gérard Vergoten.;Céline Schulz.;Julie Kerr-Conte.;Tony Lefebvre.;Vanessa Dehennaut.;Ikram El Yazidi-Belkoura.
来源: Oncogene. 2022年41卷5期745-756页
Alteration of O-GlcNAcylation, a dynamic posttranslational modification, is associated with tumorigenesis and tumor progression. Its role in chemotherapy response is poorly investigated. Standard treatment for colorectal cancer (CRC), 5-fluorouracil (5-FU), mainly targets Thymidylate Synthase (TS). TS O-GlcNAcylation was reported but not investigated yet. We hypothesize that O-GlcNAcylation interferes with 5-FU CRC sensitivity by regulating TS. In vivo, we observed that combined 5-FU with Thiamet-G (O-GlcNAcase (OGA) inhibitor) treatment had a synergistic inhibitory effect on grade and tumor progression. 5-FU decreased O-GlcNAcylation and, reciprocally, elevation of O-GlcNAcylation was associated with TS increase. In vitro in non-cancerous and cancerous colon cells, we showed that 5-FU impacts O-GlcNAcylation by decreasing O-GlcNAc Transferase (OGT) expression both at mRNA and protein levels. Reciprocally, OGT knockdown decreased 5-FU-induced cancer cell apoptosis by reducing TS protein level and activity. Mass spectrometry, mutagenesis and structural studies mapped O-GlcNAcylated sites on T251 and T306 residues and deciphered their role in TS proteasomal degradation. We reveal a crosstalk between O-GlcNAcylation and 5-FU metabolism in vitro and in vivo that converges to 5-FU CRC sensitization by stabilizing TS. Overall, our data propose that combining 5-FU-based chemotherapy with Thiamet-G could be a new way to enhance CRC response to 5-FU.
共有 7354 条符合本次的查询结果, 用时 2.2014408 秒