Effects of borneol combined with astragaloside IV and Panax notoginseng saponins regulation of microglia polarization to promote neurogenesis after cerebral ischaemia.

OBJECTIVE: To study the effect of borneol combined with astragaloside IV and Panax notoginseng saponins (BAP) on promoting neurogenesis by regulating microglia polarization after cerebral ischaemia-reperfusion(CI/R) in rats. METHODS: A focal CI/R injury model was established. Evaluated the effects of BAP on ischaemic brain injury, on promoting neurogenesis, on inhibiting Inflammatory microenvironment and TLR4/MyD88/NFκB signalling pathway. A microglia oxygen-glucose deprivation reoxygenation (OGD/R) model was established that evaluated the effects of BAP on regulating the polarization of microglia and inflammatory microenvironment. RESULTS: BAP can inhibit the expression of TLR4, MyD88 and NFκB proteins, reduce IL-1ß and increase IL-10, reduce M1 type microglia and increase M2 microglia. The proliferation of neural stem cells increased, synaptic gap decreased, synaptic interface curvature increased, expression of SYN and PSD95 proteins increased, which improved the neurological dysfunction and reduced the volume of cerebellar infarction and nerve cell injury. CONCLUSION: BAP can reduce CI/R injury and promote neurogenesis, the effect is related to inhibition of the activation of TLR4/MyD88/NFκB, regulating the polarization of microglia from M1 type to M2 type and inhibition of inflammatory response.

Monomeric C-reactive protein evokes TCR Signaling-dependent bystander activation of CD4+ T cells.

Bystander activation of T cells is defined as induction of effector responses by innate cytokines in the absence of cognate antigens and independent of T cell receptor (TCR) signaling. Here we show that C-reactive protein (CRP), a soluble pattern-recognition receptor assembled noncovalently by five identical subunits, can instead trigger bystander activation of CD4 + T cells by evoking allosteric activation and spontaneous signaling of TCR in the absence of cognate antigens. The actions of CRP depend on pattern ligand-binding induced conformational changes that result in the generation of monomeric CRP (mCRP). mCRP binds cholesterol in plasma membranes of CD4 + T cells, thereby shifting the conformational equilibrium of TCR to the cholesterol-unbound, primed state. The spontaneous signaling of primed TCR leads to productive effector responses manifested by upregulation of surface activation markers and release of IFN-γ. Our results thus identify a novel mode of bystander T cell activation triggered by allosteric TCR signaling, and reveal an interesting paradigm wherein innate immune recognition of CRP transforms it to a direct activator that evokes immediate adaptive immune responses.

Cholesterol-binding sequence is a key regulatory motif of cellular folding and conformational activation for C-reactive protein.

Human, rat, and mouse C-reactive protein (CRP) possess distinct expression patterns, but have similar conformations and conserved in vivo functions. We have previously demonstrated that this level-function mismatch is delicately tuned by the hidden activities of unfolded CRP. The cholesterol-binding sequence (CBS; a.a. 35-47) is a major functional motif exposed on monomeric CRP, which is the unfolded and activated conformation of CRP. We replaced the CBS of rat CRP with that of either mouse or human CRP, yielding two grafting mutants with unaffected pentameric assembly. However, these mutants exhibited altered cellular foldability and conformational activation efficiency that matched those of the CRP that provided the grafted CBS. These results indicate that CBS is a critical regulatory motif, whose variation maintains the pentameric assembly of CRP but derives distinct cellular foldabilities and conformational activation efficiencies, therefore helping to ensure that CRPs with various expression patterns exhibit overall conserved functions.

Ultrasound-based radiomics analysis for differentiating benign and malignant breast lesions: From static images to CEUS video analysis.

Background: Continuous contrast-enhanced ultrasound (CEUS) video is a challenging direction for radiomics research. We aimed to evaluate machine learning (ML) approaches with radiomics combined with the XGBoost model and a convolutional neural network (CNN) for discriminating between benign and malignant lesions in CEUS videos with a duration of more than 1 min. Methods: We gathered breast CEUS videos of 109 benign and 81 malignant tumors from two centers. Radiomics combined with the XGBoost model and a CNN was used to classify the breast lesions on the CEUS videos. The lesions were manually segmented by one radiologist. Radiomics combined with the XGBoost model was conducted with a variety of data sampling methods. The CNN used pretrained 3D residual network (ResNet) models with 18, 34, 50, and 101 layers. The machine interpretations were compared with prospective interpretations by two radiologists. Breast biopsies or pathological examinations were used as the reference standard. Areas under the receiver operating curves (AUCs) were used to compare the diagnostic performance of the models. Results: The CNN model achieved the best AUC of 0.84 on the test cohort with the 3D-ResNet-50 model. The radiomics model obtained AUCs between 0.65 and 0.75. Radiologists 1 and 2 had AUCs of 0.75 and 0.70, respectively. Conclusions: The 3D-ResNet-50 model was superior to the radiomics combined with the XGBoost model in classifying enhanced lesions as benign or malignant on CEUS videos. The CNN model was superior to the radiologists, and the radiomics model performance was close to the performance of the radiologists.

Neck and mediastinal hematoma caused by a foreign body in the esophagus with diagnostic difficulties: A case report.

BACKGROUND: Esophageal foreign body (FB) is a common clinical emergency. Clinically, computed tomography (CT) scans are important in the diagnosis of FBs in the esophagus. Here, we report a case of esophageal perforation and cervical hematoma, caused by a FB, whose uniqueness made rapid diagnosis difficult. CASE SUMMARY: A 42-year-old man was transferred to our hospital with esophageal perforation, which was accompanied by cervical and mediastinal hematoma. CT scans only revealed a black shadow, approximately 2.5 cm in diameter, in the upper esophagus. After multidisciplinary discussion, he was quickly subjected to mediastinal hematoma resection, peripheral nerve compression release, esophageal FB removal and esophagectomy. Eventually, we removed a small crab with a pointed tip from his esophagus. CONCLUSION: This was an unusual case of occurrence of sharp polygonal esophageal FBs caused by a small crab. Rapid diagnosis of this FB was difficult, mainly due to its translucent nature. Occurrence of sharp FBs, with cavities that sometimes only appear as black shadows on CT scans, can easily be mistaken for esophageal lumens. More attention should be paid to such sharp polygonal FBs.

Secretory quality control constrains functional selection-associated protein structure innovation.

Biophysical models suggest a dominant role of structural over functional constraints in shaping protein evolution. Selection on structural constraints is linked closely to expression levels of proteins, which together with structure-associated activities determine in vivo functions of proteins. Here we show that despite the up to two orders of magnitude differences in levels of C-reactive protein (CRP) in distinct species, the in vivo functions of CRP are paradoxically conserved. Such a pronounced level-function mismatch cannot be explained by activities associated with the conserved native structure, but is coupled to hidden activities associated with the unfolded, activated conformation. This is not the result of selection on structural constraints like foldability and stability, but is achieved by folding determinants-mediated functional selection that keeps a confined carrier structure to pass the stringent eukaryotic quality control on secretion. Further analysis suggests a folding threshold model which may partly explain the mismatch between the vast sequence space and the limited structure space of proteins.

Effects of dietary leucine and valine levels on growth performance, glycolipid metabolism and immune response in Tilapia GIFT Oreochromis niloticus.

An 8-week feeding trial was performed to evaluate the effects of dietary leucine (Leu) and valine (Val) levels on growth performance, glycolipid metabolism and immune response in Oreochromis niloticus. Fish (15.23 ± 0.05 g) were randomly fed four diets containing two Leu levels (1.2% and 2.3%) and two Val levels (0.7% and 1.4%) as a 2 × 2 experimental design (LL-LV, LL-HV, HL-LV and HL-HV). Compared with LL-LV group, the growth parameters (final weight, daily growth coefficient (DGC) and growth rate per metabolic body weight (GRMBW)), feed conversion rate (FCR), the activities of intestinal amylase, lipase, creatine kinase (CK) and Na+, K+-ATPase, liver NAD+/NADH ratio, as well as the expression of SIRT1, GK, PK, FBPase, PPARα, CPT IA, ACO and IL10 all increased significantly in the HL-LV group; however, in the high Val group, final weight, DGC, GRMBW, intestinal enzyme activities, as well as the expression of PEPCK, SREBP1, FAS, IL8 and IL10 of the HL-HV group were significantly lower than those of the LL-HV group, while the opposite was true for the remaining indicators. Significant interactions between dietary Leu and Val were observed in final weight, DGC, GRMBW, plasma IL1ß and IL6 levels, intestinal amylase and CK activities, liver NAD+/NADH ratio, as well as the expression of SIRT1, PK, PEPCK, FBPase, SREBP1, FAS, PPARα, CPT IA, ACO, NF-κB1, IL1ß, IL6 and IL10. The highest values of growth parameters, intestinal enzyme activities and expression of SIRT1, FBPase, PPARα, CPT IA and ACO were observed in the HL-LV group, while the opposite was true for the expression of SREBP1, FAS, PPARα, NF-κB1, IL1ß and IL6. Overall, our findings indicated that dietary Leu and Val can effect interactively, and fish fed with diets containing 2.3% Leu with 0.7% Val had the best growth performance and hepatic health status of O. niloticus.

Purification of Recombinant Mouse C-Reactive Protein from Pichia Pastoris GS115 by Nickel Chelating Sepharose Fast-Flow Affinity Chromatography and P-Aminophenyl Phosphoryl Choline Agarose Resin Affinity Chromatography in Tandem.

C-reactive protein (CRP) is a circulating marker of inflammation yet with ill-defined biological functions. This is partly due to the uncharacterized activities of endogenous CRP in mice, the major animal model used to define protein function. The hurdles for purification and characterization of mouse CRP are its low circulating levels and the lack of specific antibodies. To clear these hurdles, here we developed an efficient expression system by constructing recombinant Pichia pastoris cells for secretion of native conformation mouse CRP. The recombinant expression of mouse CRP in Escherichia coli failed to yield sufficient amount of native protein, reflecting the importance of post-translational modification of glycosylation in aiding proper folding. By contrast, sufficient amount of native mouse CRP was successfully purified from P. pastoris. Preliminary purification was performed by Nickel Chelating Sepharose Fast-Flow affinity chromatography with 6 × His tags attached to the protein. Subsequently, p-Aminophenyl Phosphoryl Choline Agarose resin affinity chromatography was used for tandem purification. The purified mouse CRP showed native pentamer and capabilities of PC binding. Moreover, the 6 × His tag provides a convenient tool for detecting the interactions of mouse CRP with ligands.

Borneol enhances the protective effect against cerebral ischemia/reperfusion injury by promoting the access of astragaloside IV and the components of Panax notoginseng saponins into the brain.

BACKGROUND: Astragalus and Panax notoginseng are significant traditional Chinese medicines for treating ischemic stroke, with astragaloside IV (AST IV) and Panax notoginseng saponins (PNS) being the major effective compounds, respectively. These compounds can also be used in combination. We have previously shown that AST IV and PNS have an antagonistic effect on cerebral ischemia/reperfusion (I/R) injury, and the combination of these two drugs can elevate this effect; unfortunately, AST IV and PNS cannot easily enter the brain tissues through the blood brain barrier (BBB). Previous studies have confirmed that the combination of borneol with other agents could promote the penetration of the drug components through the BBB. However, it remains unclear whether borneol can promote entry of the active components of AST IV and PNS into the brain tissues and enhance their effect against cerebral ischemia. OBJECTIVE: This study aimed to investigate the effects of a combination of borneol with AST IV and PNS against I/R injury and explore the mechanisms of borneol-promoting penetration of drug components into the BBB based on the drug transport of brain tissues. METHODS: A rat model of focal cerebral I/R injury was established, and drugs, including borneol, AST IV, and PNS, as well as their combinations were intragastrically administered. Subsequently, drug efficacy was assessed, and the condition of AST IV and PNS active components (Rg1, Rb1, R1) delivered into the brain was analyzed. Moreover, BBB permeability was determined, and the expression of related drug transporters and their genes were evaluated. RESULTS: After treatment with borneol, AST IV, PNS, AST Ⅳ+PNS, and borneol+AST Ⅳ+PNS after cerebral I/R, the neurological function deficit scores, cerebral infarct rate, and brain water content markedly decreased. The effects of the three-drug-combination were better than those of the drugs used alone and those of AST Ⅳ+PNS. Moreover, after I/R in rats, AST IV and the components of PNS (Rg1, Rb1, R1) were mainly found in the cerebral cortex and in the cerebellum, respectively, when used alone. Borneol combined with AST IV and PNS increased the contents of AST IV, Rb1, Rg1, and R1 in the cerebral cortex and in the cerebellum, thus, promoting the enrichment of active components to the cerebral cortex, especially to the affected side. In addition, following I/R, diffuse distribution of lanthanum particles in the basement membrane, intercellular and intracellular locations of rat brain tissues indicated BBB destruction and increase in permeability, which were alleviated in each drug group. The effects of borneol combined with AST IV and PNS were stronger than those of the drug single-used and those of the AST IV+PNS group. Finally, the expression of effluent transporters (ET) and their genes, including P-glycoprotein (P-gp), multidrug resistance protein (MRP)-1, MRP-2, MRP-4, and MRP-5 in brain tissues, strikingly increased after I/R. Borneol remarkedly down-regulated the protein expression of P-gp, MRP-2, and MRP-4 in the brain, whereas PNS down-regulated MRP-4 and MRP-5 protein expression. AST IV, AST IV+PNS, and bornoel+AST IV+PNS effectively decreased the expression of P-gp, MRP-2, MRP-4, and MRP-5 proteins. The effects of the three-drug combination were significantly greater than those of the drug single-used and AST IV+PNS groups. The expression of each ET gene manifested corresponding results. Meanwhile, PNS, AST IV+PNS, and bornoel+AST IV+PNS significantly inhibited the down-regulation of the uptake transporter organic anion transporting polypeptide (OATP)-2 expression, and the effect of bornoel+AST IV+PNS was stronger than that of other groups. CONCLUSION: After I/R, the brain tissues were injured, BBB permeability increased, expression of critical ET and their genes were markedly up-regulated, and the main uptake transporters were down-regulated. We propose that the combination of borneol, AST IV and PNS could enhance the effect against cerebral I/R injury and protect BBB integrity. The potential mechanism might be the delivery of AST IV and active components of PNS to the brain tissues after treatment in combination with borneol, which could be effectively promoted by down-regulating the expression of ETs and up-regulating the expression of uptake transporters in the brain tissues. This study was the first to demonstrate that borneol combined with AST IV+PNS enhanced the effect against cerebral I/R injury through promoting the entry of AST and PNS active components to the brain tissues. Thus, this study proposes an instructive role in developing effective active ingredients combination of Chinese medicine with clear ingredients and synergistic effects in terms of the characteristic of borneol.

Traceability of the geographical origin of Siraitia grosvenorii based on multielement contents coupled with chemometric techniques.

Siraitia grosvenorii (LHG) is widely used as a medicinal and edible material around the world. The objective of this study was to develop an effective method for the authentication of the geographical origin of LHG in its main producing area Guangxi, China, which is identified as Chinese Protected Designation of Origin product, against other producing regions in China. The content of 14 elements (K, Na, Ca, P, Mg, Al, B, Ba, Cu, Fe, Mn, Ni, Zn, and Sr) of 114 LHG samples was determined by inductively coupled plasma optical emission spectrometry. Multivariate analysis was then performed to classify the geographical origin of LHG samples. The contents of multielement display an obvious trend of clustering according to the geographical origin of LHG samples based on radar plot and principal component analysis. Finally, three supervised statistical techniques, including linear discriminant analysis (LDA), k-nearest neighbours (k-NN), and support vector machine (SVM), were applied to develop classification models. Finally, 40 unknown LHG samples were used to evaluate the predictive ability of model and discrimination rate of 100%, 97.5% and 100% were obtained for LDA, k-NN, and SVM, respectively. This study indicated that it is feasible to attribute unknown LHG samples to its geographical origin based on its multielement content coupled with chemometric techniques.

Molecular characterization of thioredoxin-interacting protein (TXNIP) from Megalobrama amblycephala and its potential roles in high glucose-induced inflammatory response.

This study aimed to characterize the full-length cDNA of thioredoxin-interacting protein (TXNIP) from Megalobrama amblycephala, and investigate its roles in high glucose (HC)-induced inflammatory response. The cDNA obtained covered 2706-bp with an open reading frame of 1203-bp encoding 400 amino acids, compared to Cyprinus carpio, it showed 89.96% homology. The highest expression of txnip was observed in head kidney followed by spleen and liver. After a 12-week feeding trial, high-carbohydrate diet remarkably increased txnip expression in liver and white muscle. Glucose administration resulted in a remarkably increased liver txnip expression, which peaked at 1 h. Thereafter, the expression decreased remarkably to the basal value at 12 h. However, insulin injection resulted in a significant decrease in txnip expression with minimum values attained at 2 h. Subsequently, it gradually increased to the normal values. Moreover, in the in-vitro study, over-expression of txnip along with remarkably increased il-1ß and il-6 expression in hepatocytes, and its knockdown led to remarkably reduced il-1ß expression. Furthermore, metformin treatment remarkably increased the cell viability and trx expression of hepatocytes under high glucose, while the opposite was true for ROS levels, LDH activity, the ALT/AST ratio, Txnip protein content and the transcriptions of txnip, tnfα and il-1ß.

MicroRNA-361-5p Inhibits Tumorigenesis and the EMT of HCC by Targeting Twist1.

MicroRNA-361-5p (miR-361-5p) is a tumor suppressor miRNA that is dysregulated in several types of human cancer. However, the functional significance of miR-361-5p in hepatocellular carcinoma (HCC) is unclear. This study explored the biological function of miR-361-5p in regulating the progression of HCC and the underlying molecular mechanism. RT-qPCR analysis showed that miR-361-5p was downregulated in HCC tissues and cell lines. Functional analysis revealed that miR-361-5p acted as a tumor suppressor, inhibiting cell proliferation, migration, and invasion in HCC cell lines. Bioinformatics analyses identified Twist1 as a direct target of miR-361-5p, which was validated by dual-luciferase reporter assays, RT-qPCR, and western blotting. Rescue experiments indicated that Twist1 may mediate the tumor-suppressive effect of miR-361-5p in HCC cells, and this was supported by the effect of miR-361-5p on inhibiting the epithelial-mesenchymal transition (EMT) by targeting Twist1. This study is the first to suggest that miR-361-5p inhibits tumorigenesis and EMT in HCC by targeting Twist1. These findings are valuable for the diagnosis and clinical management of HCC.

Longevity and sustainability of tropical and subtropical restored seagrass beds among Atlantic, Pacific, and Indian Oceans.

Seagrass longevity up to 47 years in well-restored, well-sited seagrass restorations are demonstrated from 253 trials at 83 regional sites in tropical and subtropical portions of three oceans (Atlantic, Pacific, Indian Oceans). These trials include over 3.04 million planted units into 306.3 ha. Approximately 12% of the total global tropical restored seagrass by Van Katwijk, Thorhaug et al. (2016) calculations from 1786 trials are included. Almost all projects herein reviewed persisted since date of planting except several cases with harsh anthropogenic impact or forceful natural events in first post-planting months. The oldest tropical/subtropical restoration continually observed is 47 yrs, many are 35 yrs. An array of observed and/or measured restored services accompanied these. This review may provide informational background for government resource managers, legislators, scientists, and citizens concerning tropical/subtropical seagrass longevity. This data from these trials may substantiate future seagrass restoration investments. Public outreach, national & regional government training,and outreach occurred, needing continuation.

Five Active Components Compatibility of Astragali Radix and Angelicae Sinensis Radix Protect Hematopoietic Function Against Cyclophosphamide-Induced Injury in Mice and t-BHP-Induced Injury in HSCs.

Although the compatibility of Astragali Radix (AR) and Angelicae Sinensis Radix (ASR) has favorable effect on promoting hematopoiesis in traditional Chinese medicine (TCM), the main active components and pharmacological mechanism are unknown. We investigated the five active components and its mechanisms in vitro and in vivo. Five active components of Astragalus glycosides (AST), Formononetin (FRM), Ferulic acid (FRA), Calycosin (CAL), and Calycosin-7-glucoside (CLG), which could be absorbed in intestinal tract, were detected in this study. The peripheral blood, hematopoietic growth factors (HGFs), and hematopoietic progenitor cells (HPCs) colony were observed to evaluate the effect of these five active components promoting hematopoiesis. Furthermore, hematopoietic stem cell (HSC) proliferation, aging, cycle, and related proteins were detected to explore the mechanism of these five components promoting HSC proliferation. i) The in vivo experiments showed that the combination of the five active components could remarkably increase the number of RBCs, WBCs, PLTs, and content of Hb in peripheral blood and the area of bone marrow hematopoietic tissue, as well as thrombopoietin (TPO), erythropoietin (EPO), granulocyte-macrophage colony stimulating factor (GM-CSF), and colony of CFU-GM, CFU-MK, CFU-E, and BFU-E in serum. Each of these five components promoted the recovery of RBCs and Hb, and increased TPO, CFU-MK, and CFU-E. All components except for AST increased the CFU-GM. FRA increased the number of WBCs, the area of bone marrow hematopoietic tissue, and BFU-E. FRA and AST promoted PLT recovery. FRA and CAL improved the content of GM-CSF. FRA, CAL, and CLG improved the content of EPO. ii) The in vitro experiments showed that FRA, FRM, and AST significantly promoted cell proliferation, reduced the positive rate and G0/G1 cells, and increased G2/M + S cells and the expression of cyclin D1 and CDK4 proteins in aging HSCs. Furthermore, the combination of five components had the best effect. Taken together, the five active components of AST, FRM, FRA, CAL, and CLG were the main pharmacodynamic substances of the AR-ASR compatibility, which promoted hematopoiesis. The combination of them had a synergistic effect. The mechanism of promoting hematopoiesis may be relevant to regulating cyclin-related proteins, promoting cell cycle transformation, and promoting HSC proliferation.

Dose Escalation of Lobaplatin Concurrent with IMRT for the Treatment of Stage III-IVb NPC: A Phase I Clinical Trial.

The maximum tolerated dose (MTD) of lobaplatin as a single agent chemotherapy concurrent with intensity-modulated radiotherapy (IMRT) in Asian population with nasopharyngeal carcinoma (NPC) remains unclear. From June 2016 to December 2017, 17 patients diagnosed with stage III-IVb NPC from an Asian population were prospectively enrolled. Patients were administered lobaplatin with 25-50 mg/m2 escalation of dosage on day 1. Every 21 days (days 1, 22, and 43) during radiotherapy, cycles were repeated. We administered radiotherapy as 2.12-2.27 Gy per fraction with five daily fractions each week for 6 to 7 weeks. The evaluation of lobaplatin-related toxic effects was based on the Common Terminology Criteria for Adverse Events version 4.0. During the weekly treatment period, complete blood counts and biochemistry were performed. Dose-limiting toxicities (DLTs) were determined by the following events during any cycle in which lobaplatin was administered. Each dose group consisted of at least three cases. We proceeded to the subsequent dose group in the absence of DLT with a dose increment of 5 mg/m2 until DLT occurred. Periods from 1 week prior to the chemotherapy initiation to 3 weeks after the last chemotherapy were defined as DLT observation periods. MTD was determined by the dose that was immediately below the dose that produced DLT. After analysis, DLT occurred in three patients, including a group with two of three patients in 45 mg/m2 lobaplatin and another group with one of five patients in 40 mg/m2 lobaplatin. No grade 3-4 toxicity was observed in patients treated with lobaplatin <40 mg/m2. The tumor response rate at 12 weeks after treatment was 100%. In summary, lobaplatin concurrent with IMRT was active in stage III-IVb NPC, and the MTD for the lobaplatin as single-agent chemotherapy was 40 mg/m2 when combined with IMRT in an Asian population. This trial is registered with ClinicalTrials.gov, number NCT03188497.

Cell surface expression of nucleolin mediates the antiangiogenic and antitumor activities of kallistatin.

Kallistatin is a unique serine proteinase inhibitor and heparin-binding protein. A previous study conducted by our group indicated that kallistatin has antiangiogenic and antitumoral activities. In the present study, we report that kallistatin specifically binds to membrane surface-expressed nucleolin with high affinity. Antibody-mediated neutralization or siRNA-induced nucleolin knockdown results in loss of kallistatin suppression of endothelial cell proliferation and migration in vitro and tumor angiogenesis and growth in vivo. In addition, we show that kallistatin is internalized and transported into cell nuclei of endothelial cells via nucleolin. Within the nucleus, kallistatin inhibits the phosphorylation of nucleolin, which is a critical step required for cell proliferation. Thus, we demonstrate that nucleolin is a novel functional receptor of kallistatin that mediates its antiangiogenic and antitumor activities. These findings provide mechanistic insights into the inhibitory effects of kallistatin on endothelial cell growth, tumor cell proliferation, and tumor-related angiogenesis.

Entinostat reverses cisplatin resistance in esophageal squamous cell carcinoma via down-regulation of multidrug resistance gene 1.

Cisplatin resistance frequently occurs in esophageal squamous cell carcinoma (ESCC). The underlying mechanism for cisplatin resistance in ESCC remains largely obscure. Here we report that entinostat reversed cisplatin resistance in ESCC both in vitro and in vivo by induction of apoptosis and inhibition of cell proliferation, accompanied by a decrease of multidrug resistance gene 1 (MDR1), P-Src, Mcl-1, Cyclin D1 and an increase of cleaved PARP. MDR1 expression was associated with worsen survival of ESCC patients with cisplatin-based chemotherapy. Dasatinib potentiated entinostat to overcome cisplatin resistance. By inhibiting Src, dasatinib reduced the expression of MDR1 and Mcl-1. Furthermore, Obatoclax, an inhibitor of Mcl-1, obviously decreased the expression of MDR1, suggesting that entinostat might surmount cisplatin resistance in ESCC via a Src-Mcl-1-MDR1 pathway. Interestingly, cisplatin also enhanced the effect of entinostat both in vitro and in vivo. Our data disclose a molecular basis that entinostat reverses cisplatin resistance, and provide a promising strategy with combinatorial drugs to treat cisplatin resistant ESCC patients.