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The variable dosage forms of most traditional Chinese medicines (TCMs) could be disadvantaged by low selectivity, poor biological distribution, limited bioavailability with low efficacy, and some adverse effects. These issues limit the control of clinical pharmacodynamics of the antitumor active components. With the progress of science and technology, many new polymer materials and new technologies have emerged, such as nanotechnology, cyclodextrin inclusion, solid dispersion, microcapsule and microsphere technologies. These new technologies provide a good basis for exploring novel TCM dosage forms for overcoming the shortcomings. The increased numbers of new technologies have been used to study TCM dosage forms with remarkable achievements. In this review paper, we will provide a systematic overview of the new dosage forms of nano-formulations and co-medications in relation to nano-delivery systems in an attempt to provide useful references for practical application of active antitumor ingredients from the TCMs.

Piper longum L., an herbal medicine used in India and other Asian countries, is prescribed routinely for a range of diseases, including tumor. Piperlongumine, a natural product isolated from Piper longum L., has received widespread attention due to its various pharmacological activities, such as anti-inflammatory, antimicrobial, and antitumor effects.Chronic myelogenous leukemia (CML) is a hematopoietic disease caused by Bcr-Abl fusion gene, with an incidence of 15% in adult leukemias. Targeting Bcr-Abl by imatinib provides a successful treatment approach for CML. However, imatinib resistance is an inevitable issue for CML treatment. In particular, T315I mutant is the most stubborn of the Bcr-Abl point mutants associated with imatinib resistance. Therefore, it is urgent to find an alternative approach to conquer imatinib resistance. This study investigated the role of a natural product piperlongumine in overcoming imatinib resistance in CML.Cell viability and apoptosis were evaluated by MTS assay and Annexin V/propidium iodide counterstaining assay, respectively. Levels of intracellular signaling proteins were assessed by Western blots. Mitochondrial membrane potential was reflected by the fluorescence intensity of rhodamine-123. The function of proteasome was detected using 20S proteasomal activity assay, proteasomal deubiquitinase activity assay, and deubiquitinase active-site-directed labeling. The antitumor effects of piperlongumine were assessed with mice xenografts.We demonstrate that (i) Piperlongumine inhibits proteasome function by targeting 20S proteasomal peptidases and 19S proteasomal deubiquitinases (USP14 and UCHL5) in Bcr-Abl-WT and Bcr-Abl-T315I CML cells; (ii) Piperlongumine inhibits the cell viability of CML cell lines and primary CML cells; (iii) Proteasome inhibition by piperlongumine leads to cell apoptosis and downregulation of Bcr-Abl; (iv) Piperlongumine suppresses the tumor growth of CML xenografts.These results support that blockade of proteasome activity by piperlongumine provides a new therapeutic strategy for treating imatinib-resistant CML.

Background: Combination of the prodrug technique with an albumin nanodrug-loaded system is a novel promising approach for cancer treatment. However, the long-lasting and far-reaching challenge for the treatment of cancers lies in how to construct the albumin nanometer drug delivery system with lead compounds and their derivatives. Results: In this study, we reported the preparation of injectable albumin nanoparticles (NPs) with a high and quantitative drug loading system based on the NabTM technology of paclitaxel palmitate (PTX-PA). Our experimental study on drug tissue distribution in vivo demonstrated that the paclitaxel palmitate albumin NPs (Nab-PTX-PA) remained in the tumor for a longer time post injection. Compared with saline and Abraxane® (nanoparticle albumin-bound (nab)-paclitaxel), intravenous injection of Nab-PTX-PA not only reduced the toxicity of the drug in normal organs and increased the body weight of the animals but maintained sustained release of paclitaxel (PTX) in the tumor, thereby displaying an excellent antitumor activity. Blood routine analysis showed that Nab-PTX-PA had fewer adverse effects or less toxicity to the normal organsand more importantly it inhibited tumor cell proliferation more effectively as compared with commercial Abraxane®.Conclusions: This carrier strategy for small molecule drugs is based on naturally evolved interactions between LCFAs(Long Chain Fatty Acids) and HSA(human serum albumin), demonstrated here for PTX. Nab-PTX-PA shows higher maximum tolerated doses and increased efficacy in vivo in breast cancer models, as compared to Abraxane for FDA-approved clinical formulations. This novel injectable Nab-PTX-PA platform has great potential as an effective drug delivery system in the treatment of breast cancer.

Bone-metastasis prostate cancer (BMPCa)-targeting gene therapy is gaining increasing concern in recent years. The peptide T7-modified polypeptide nanoparticles for delivery DNA (CRD-PEG-T7/pPMEPA1) was prepared as our previous study. However, the feasibility of CRD-PEG-T7/pPMEPA1 for BMPCa treatment, the mechanisms underlying cellular uptake, anti-BMPCa effect, and administration safety requires further research. LNCaP cells treated with endocytosis inhibitors and excessive T7 under different culture condition were carried out to investigate the mechanisms of cellular uptake of the CRD-PEG-T7-pPMEPA1. A transwell assay was applied to evaluate the cell migration ability. Besides, the tumor volume and survival rates of the PCa xenograft mice model were recorded to estimate the anti-tumor effect. In addition, the weight profiles of the PCa tumor-bearing mice, the blood chemistry, and the HE analysis of visceral organs and tumor was conducted to investigate the administration safety of CRD-PEG-T7/pPMEPA1. The results showed that PCa cellular uptake was decreased after treating with excessive free T7, endocytosis inhibitors and lower incubation temperature. Besides, CRD-PEG-T7/pPMEPA1 could inhibit the LNCaP cells chemotaxis and tumor growth. In addition, the survival duration of the PCa tumor-bearing mice treating with CRD-PEG-T7/pPMEPA1 was significantly prolonged with any systemic toxicity or damage to the organs. In conclusion, this research proposes a promising stratagem for treatment BMPCa by providing the biocompatible and effective carrier for delivery DNA therapeutic agents.

Background Positioning stent in head and neck radiotherapy seems to have benefit to prevent oral complications but it hasn’t been summarized by an evidence-based method. Objectives This review aims to evaluate the efficacy of positioning stents in preventing oral complications after radiotherapy. Methods We conducted an electronic search in MEDLINE, EMBASE, Cochrane CDSR, and Cochrane CENTRAL database for randomized-controlled clinical trials, controlled clinical trials and cohort studies that assessed oral complications after head and neck radiotherapy with positioning stents. Two reviewers extracted information on radiotherapy, follow-up period, oral complications and assessments independently. Results Three RCTs and two cohort studies were included in this review. Oral complications such as mucositis, xerostomia, taste alteration, trismus, salivary changes, dysphagia and pain on swallowing were assessed by different methods in these studies. Conclusions Oral complications were common in patients after head and neck radiotherapy. There is insufficient evidence that positioning stents have a preventive effect against xerostomia, and it needs more high-quality and prospective trials with long-term follow-up to support it.

AIM The objectives of this laboratory-based study were to investigate the effects of GH12 on Enterococcus faecalis biofilm and virulence. METHODOLOGY Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of GH12 against E. faecalis were first determined. A time-kill assay was further conducted. The effects of GH12 on the expression of virulence and stress genes in E. faecalis were evaluated by RT-qPCR. Crystal violet stain was used to investigate the effects of GH12 on E. faecalis biofilm formation and 1-day-old biofilm. Finally, an ex vivo tooth model contaminated with E. faecalis was used to evaluate the antimicrobial activity of GH12 as an irrigant by CFU counting, SEM and CLSM. One-way anova and Tukey's multiple comparisons test were used to compare the differences amongst groups (α = 0.05). RESULTS The MICs and MBCs of GH12 against E. faecalis were 8.0 ± 0.0 and 16.0 ± 0.0 mg L-1 , respectively, and GH12 at 32.0 mg L-1 reduced the bacterial numbers by more than 99.9% within 1 min. Various virulence genes (efaA, esp and gelE) and stress genes (dnaK, groEL, ctsR and clpPBCEX) in E. faecalis were significantly downregulated by GH12 at sub-MIC levels (P

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. The prognosis of HCC remains very poor; thus, an effective treatment remains urgent. Herein, a type of nanomedicine is developed by conjugating Fe@Fe3 O4 nanoparticles with ginsenoside Rg3 (NpRg3), which achieves an excellent coupling effect. In the dimethylnitrosamine-induced HCC model, NpRg3 application significantly prolongs the survival of HCC mice. Further research indicates that NpRg3 application significantly inhibits HCC development and eliminates HCC metastasis to the lung. Notably, NpRg3 application delays HCC-induced ileocecal morphology and gut microbial alterations more than 12 weeks during HCC progression. NpRg3 administration elevates the abundance of Bacteroidetes and Verrucomicrobia, but decreases Firmicutes. Twenty-nine predicted microbial gene functions are enriched, while seven gene functions are reduced after NpRg3 administration. Moreover, the metabolomics profile presents a significant progression during HCC development, but NpRg3 administration corrects tumor-dominant metabolomics. NpRg3 administration decreases 3-indolepropionic acid and urea, but elevates free fatty acids. Importantly, NpRg3 application remodels the unbalanced correlation networks between gut microbiota and metabolism during HCC therapy. In conclusion, nanoparticle conjugation of ginsenoside Rg3 inhibits HCC development and metastasis via the remodeling of unbalanced gut microbiota and metabolism in vivo, providing an antitumor therapy strategy.

Aim. Microvessel density is a marker of tumor angiogenesis activity for development and metastasis. Our preliminary study showed that ginsenoside Rg3 (Rg3) induces apoptosis in hepatocellular carcinoma (HCC) in vitro. The aim of this study was to investigate the cross-link for apoptosis induction and antiangiogenesis effect of Rg3 on orthotopic HCC in vivo. Methods. The murine HCC cells Hep1-6 were implanted in the liver of mouse. With oral feeding of Rg3 (10 mg/kg once a day for 30 days), the quantitative analysis of apoptosis was performed by using pathology and a transmission electron microscope and microvessel density was quantitatively measured by immunohistochemical staining of the CD105 antibody. The mice treated with Rg3 (n=10) were compared with the control (n=10) using Kaplan-Meier analysis. Animal weight and tumor weight were measured to determine the toxicity of Rg3 and antitumor effect on an orthotopic HCC tumor model. Results. With oral feeding of Rg3 daily in the first 30 days on tumor implantation, Rg3 significantly decreased the orthotopic tumor growth and increased the survival of animals (P<0.05). Rg3-treated mice showed a longer survival than the control (P<0.05). Rg3 treatment induced apoptosis and inhibited angiogenesis. They contributed to the tumor shrinkage. Rg3 initialized the tumor apoptotic progress, which then weakened the tumor volume and its capability to produce the vascularized network for further growth of the tumor and remote metastasis. Conclusion. Rg3 inhibited the activation of microtumor vessel formation in vivo besides its apoptosis induction. Rg3 may be used as an adjuvant agent in the clinical HCC treatment regimen.

Aim The aim was to evaluate the incidence and type of defects that occurred with K3 rotary nickel–titanium instruments during routine clinical use. Methodology A total of 2397 K3 (G-PACKS, SybronEndo, West Collins, Orange, CA, USA) instruments were collected from a graduate endodontic clinic over 21 months. All the instruments were limited to a maximum use of 30 canal preparations. The collected instruments were measured by a digital caliper to determine whether any fractures had occurred and then were visually inspected for deformation and fracture under a stereomicroscope. The surfaces of fractured instruments were further evaluated under a scanning electron microscope. Data were analysed using chi-square test and Kruskal–Wallis test. Results The incidence of instrument defect was 5.63%, consisting of 3.59% fractures and 2.05% deformations. The defect rates of 0.04 and 0.06 files were statistically higher than the other taper groups (P 0.05). For the fractured instruments, 63.95% failed from flexural fatigue, whilst 36.05% failed from torsion. Conclusion Flexural fracture was the major mode of fracture for instruments with larger taper. A routine check for instrument integrity particularly for 0.04 and 0.06 files at high magnification is recommended after each clinical use.

Convergence factor and steady-state error are a pair of inherent contradictions in fixed step size LMS algorithm. For a long time, how to balance the two has been the focus of research. This paper analyzed the fixed step LMS algorithm, proposed a variable step LMS algorithm, and combined them with the multiscale wavelet transform algorithm to propose a new algorithm to solve this problem. From the Maltab simulation results, it can be seen that the new algorithm solved the problem between them to a certain extent, and had stronger noise suppression ability and faster convergence speed.

Although increasing evidence has documented the association of exposure to air pollution and childhood obesity, a limited number of studies have reported the relationship of air pollution exposure to early childhood body mass index (BMI) growth trajectories, which are strong predictors of future health. We aimed to examine the associations of prenatal and postnatal (first-year and second-year) exposure to nitrogen dioxide (NO2) and indicators of exposure to major roadways with obesity at 2 years old and BMI-for-age Z-score (BMIZ) growth trajectories between 0 and 2 years old. The length and weight of the children were repeatedly measured at birth and at 1 year (±1 month) and 2 years (±1 month) of age. Sex-specific BMIZs were calculated, and children with BMIZs greater than the 95th percentile were identified as cases of obesity (BMIZ cut-offs of childhood obesity were 1.78 for boys and 1.60 for girls). Exposure to NO2 was evaluated using a land use regression model. Two indicators for major roadways exposure (length of major roadways surrounding the residence and residential distance to the nearest major roadway) were calculated according to the residential address during pregnancy. We explored the prenatal NO2 exposure windows associated with incident obesity at 2 years old and found that the third trimester was the prenatal NO2 exposure window with the significant higher risk. Each 10 μg/m3 incremental change in prenatal exposure to NO2 was associated with a relative risk (RR) of 1.10 for childhood obesity (95% confidence interval: 1.01, 1.20). However, postnatal (first-year and second-year) exposure to NO2 was not associated with obesity risk at 2 years old. No significant associations were observed between indicators of exposure to major roadways and risk of obesity at 2 years old. In addition, prenatal exposure to the highest quartile of NO2 was significantly associated with a faster overall growth rate of the BMIZ from birth to the age of 2 years old (the slope of the BMIZ trajectories, β3 (standard error), for the 4th quartile vs. the 1st quartile: 0.88 (0.15), P value

Drug-induced gene expression patterns that invert disease profiles have recently been illustrated to be a new strategy for drug-repositioning. In the present study, we validated this approach and focused on prediction of novel drugs for lung adenocarcinoma (AC), for which there is a pressing need to find novel therapeutic compounds. Firstly, connectivity map (CMap) analysis computationally predicted bezafibrate as a putative compound against lung AC. Then this hypothesis was verified by in vitro assays of anti-proliferation and cell cycle arrest. In silico docking evidence indicated that bezafibrate could target cyclin dependent kinase 2(CDK2), which regulates progression through the cell cycle. Furthermore, we found that bezafibrate can significantly down-regulate the expression of CDK2 mRNA and p-CDK2. Using a nude mice xenograft model, we also found that bezafibrate could inhibit tumor growth of lung AC in vivo. In conclusion, this study proposed bezafibrate as a potential therapeutic option for lung AC patients, illustrating the potential of in silico drug screening.

A new surgical approach (subadventitial cystectomy) has been developed for liver hydatid disease. We retrospectively compared clinical outcomes and immune status 24 months after a subadventitial cystectomy with traditional surgical approaches. Patients with liver hydatid cysts were treated with a subadventitial cystectomy (N = 11), pericystectomy (N = 16), partial pericystectomy (N = 18), or hepatic resection (N = 12). By the end of the follow-up period, the subadventitial cystectomy group had the fewest post-operative complications and shortest hospital stays. Two recurrences occurred: one recurrence after partial pericystectomy and one recurrence after pericystectomy. The total immunoglobulin E (IgE) level decreased significantly in the subadventitial cystectomy group. The post-surgery IgG level was lower in the subadventitial cystectomy than the pericystectomy and partial pericystectomy groups. In conclusion, subadventitial cystectomy completely removes the parasite, causing lower complication rates and lower immune reactions.

Background Residential surrounding green spaces can affect human health. However, limited studies have examined their impacts on maternal blood glucose homeostasis outcomes. Objective We examined the associations of residential exposure to green space with maternal blood glucose levels, gestational impaired glucose tolerance (IGT), and gestational diabetes mellitus (GDM). Methods Pregnant women were recruited from a prospective birth cohort between October 2012 and September 2015. Exposure to green space was calculated as the mean value of the normalized difference vegetation index (NDVI) within a 300-m circular buffer area surrounding each residence. Maternal glucose was measured between 24 and 28 weeks of gestation, and gestational IGT and GDM were diagnosed using valid methods. We estimated the associations of residential NDVI with maternal glucose levels using multiple linear regression models with adjustment for age, education, BMI, passive smoking during pregnancy, parity, season of conception, income, and urbancity. We estimated the relative risks of residential NDVI with IGT and GDM using a generalized estimating equation model with modified Poisson regression. The mediation effects of residential exposure to air pollution and maternal physical activity were assessed using causal mediation analysis. Results Of 6807 pregnant women, 751 (11.3%) and 604 (8.8%) were diagnosed with IGT and GDM, respectively. One SD increment of residential NDVI was associated with a decrease of 0.06 mmol/L (95% CI: −0.07, −0.05), 0.09 mmol/L (95% CI: −0.13, −0.05), and 0.06 mmol/L (95% CI: −0.09, −0.03) in maternal fasting glucose levels, 1-h glucose levels, and 2-h glucose levels, respectively, as well as reduced risks of incident IGT (RR: 0.92, 95% CI: 0.86, 0.99) and GDM (RR: 0.85, 95% CI: 0.79, 0.92). The association between residential NDVI and maternal fasting glucose levels was partly mediated by maternal exposure to PM2.5. Conclusion Living with higher levels of green space was significantly associated with decreased maternal glucose levels and attenuated risks of incident maternal IGT and GDM. Our findings provide evidence linking green space to better maternal glucose outcomes. More studies are needed to further explore the maternal and child health benefits related to our findings.

The tree mortality model plays an important role in simulating stand dynamic processes. Past work has shown that the disaggregation method was successful in improving tree survival prediction. This method was used in this study to forecast tree survival probability of Chinese pine (Pinus tabulaeformis Carrière) in Beijing. Outputs from the tree survival model were adjusted from either the stand-level model prediction or the combined estimator from the forecast combination method. Our results show that the disaggregation approach improved the performance of tree survival models. We also showed that stand-level prediction played a crucial role in refining outputs from a tree survival model, especially when it is a very simple model. Because the forecast combination method produced better stand-level prediction, we prefer the use of this method in conjunction with the disaggregation approach, even though the performance gain in using the forecast combination method shown for this data set was modest.

Carbonaceous aerosol is one of the main ingredients of the atmospheric aerosol, which includes black carbon and organic carbon. The numerical simulations from 1960 to 2000 are aimed at the direct radiative effects on climate induced by carbonaceous aerosol in East Asia using NCAR Community Atmospheric Model version 3.1 (CAM). The mean radiative forcing(RF) under all sky in Chinese mainland at TOA and surface are 0.38 and −5.31W/m2 respectively. This distinct RF leads to −0.1K surface temperature decrease in Chinese mainland, which includes −0.26K drop of daily maximum and 0.07K rise of minimum temperature. Air column temperature has also been increased 0.11K in Chinese mainland. Significant vapor and precipitation increase can be resulted from RF of carbonaceous aerosol in north China and the Yellow and Huai River basin, accompanied by the decrease in northeast China, far-east region, and Tibet Plateau.

Like many other receptor tyrosine kinases (RTKs), platelet-derived growth factor (PDGF) receptor beta (PDGFR-beta) is internalized and degraded in lysosomes in response to PDGF stimulation, which regulates many aspects of cell signalling. However, little is known about the regulation of PDGFR-beta endocytosis. Given that ligand binding is essential for the rapid internalization of RTKs, the events induced by the ligand binding likely contribute to the regulation of ligand-induced RTK internalization. These events include receptor dimerization, activation of intrinsic tyrosine kinase activity and autophosphorylation. In this communication, we examined the role of PDGFR-beta kinase activity, PDGFR-beta dimerization and PDGFR-beta C-terminal motifs in PDGF-induced PDGFR-beta internalization. We showed that inhibition of PDGFR-beta kinase activity by chemical inhibitor or mutation did not block PDGF-induced PDGFR-beta endocytosis, suggesting that the kinase activity is not essential. We further showed that dimerization of PDGFR-beta is essential and sufficient to drive PDGFR-beta internalization independent of PDGFR-beta kinase activation. Moreover, we showed that the previously reported 14 amino acid sequence 952-965 is required for PDGF-induced PDGFR-beta internalization. Most importantly, we showed that this PDGFR-beta internalization motif is exchangeable with the EGFR internalization motif (1005-1017) in mediating ligand-induced internalization of both PDGFR-beta and EGFR. This indicates a common mechanism for the internalization of both PDGFR-beta and EGFR.

A recent study has shown that nanosecond pulsed electric fields (nsPEF) can affect the intracellular structures of melanoma within weeks. nsPEF is a non-drug, non-thermal treatment using ultrashort, intense pulsed electric fields with nanosecond durations. In the current study we followed up melanoma histopathology and metastasis with tissue micro-array 5 months post-nsPEF. After nsPEF treatment, tumor growth, tumor histology, metastasis, peri-tumor vessel and micro-vessel density were examined for the effect of nsPEF treatment on melanoma in vivo. The 17 nsPEF-treated mice were tumor-free for 169 days, significantly longer than those 19 control mice bearing melanoma without nsPEF. Histopathology follow-up showed that melanoma did not recur to the primary injection place after complete elimination. Compared with the control tumor, nsPEF-treated tumors present decreased micro-vessel density in a time-course manner in this survival study. Treatment with nsPEF caused continuous histopathological changes in melanomas, eliminated melanoma without recurrence at the primary site and prolonged animal survival time by inhibiting tumor blood supply and leading to tumor infarction. Thus, nsPEF could be applied in a non-ionizing therapeutic approach, without other agents, to locally treat tumors within a defined boundary.

Unresectable hepatocellular carcinoma (HCC) needs locoregional ablation as a curative or downstage therapy. Microsecond Pulsed Electric Fields (μsPEFs) is an option. A xenograft tumor model was set up on 48 nude mice by injecting human hepatocellular carcinoma Hep3B cells subcutaneously. The tumor-bearing mice were randomly divided into 3 groups: μsPEFs treated, sham and control group. μsPEFs group was treated by μsPEFs twice in 5 days. Tumor volume, survival, pathology, mitochondria function and cytokines were followed up. μsPEFs was also conducted on 3 swine to determine impact on organ functions. The tumors treated by μsPEFs were completely eradicated while tumors in control and sham groups grew up to 2 cm3 in 3 weeks. The μsPEFs-treated group indicated mitochondrial damage and tumor necrosis as shown in JC-1 test, flow cytometry, H&E staining and TEM. μsPEFs activates CD56+ and CD68+ cells and inhibits tumor proliferating cell nuclear antigen. μsPEFs inhibits HCC growth in the nude mice by causing mitochondria damage, tumor necrosis and non-specific inflammation. μsPEFs treats porcine livers without damaging vital organs. μsPEFs is a feasible minimally invasive locoregional ablation option.

We have shown that epidermal growth factor (EGF) receptor (EGFR) endocytosis is controlled by EGFR dimerization. However, it is not clear how the dimerization drives receptor internalization. We propose that EGFR endocytosis is driven by dimerization, bringing two sets of endocytic codes, one contained in each receptor monomer, in close proximity. Here, we tested this hypothesis by generating specific homo- or hetero-dimers of various receptors and their mutants. We show that ErbB2 and ErbB3 homodimers are endocytosis-deficient due to the lack of endocytic codes. Interestingly, EGFR-ErbB2 or EGFR-ErbB3 heterodimers are also endocytosis-deficient. Moreover, the heterodimer of EGFR and the endocytosis-deficient mutant EGFRΔ1005–1017 is also impaired in endocytosis. These results indicate that two sets of endocytic codes are required for receptor endocytosis. We found that an EGFR/PDGFR heterodimer is endocytosis-deficient, although both EGFR and PDGFR homodimers are endocytosis-competent, indicating that two compatible sets of endocytic codes are required. Finally, we found that to mediate the endocytosis of the receptor dimer, the two sets of compatible endocytic codes, one contained in each receptor molecule, have to be spatially coordinated.

Background To identify the chemical structure of Coreopsis tinctoria extracts and their effect and mechanism on reducing blood lipid in hyperlipemia mice. Methods The flavonoids were extracted from Coreopsis tinctoria. The chemical structure was identified by HPLC. 59 mice were divided randomly into 5 groups. (group 1: normal diet control; group 2: hyperlipemia model; group 3: hyperlipemia mice treated with Coreopsis tinctoria, low dose 100 mg/kg; group 4: hyperlipemia mice treated with Coreopsis tinctoria high dose group 200 mg/kg; group 5 hyperlipemia mice treated with Fenofibrate. After 2 week of hyperlipid diet, the treatment of Coreopsis tinctoria and Fenofibrate were given for another 6 weeks with continuous hyperlipid diet. The TC, TG, HDL, histology, adipose differentiation-related protein (ADRP) expression in different groups were compared. Results Compared with normal diet group, TC, TG in hyperlipemia model group increased ( P

In spite of intensified efforts to understand cell signaling from endosomes, there is no direct evidence demonstrating that endosomal signaling is sufficient to activate signal transduction pathways and no evidence to demonstrate that endosomal signaling is able to produce a biological outcome. The lack of breakthrough is due in part to the lack of means to generate endosomal signals without plasma membrane signaling. In this paper, we report the establishment of a system to specifically activate epidermal growth factor (EGF) receptor (EGFR) when it endocytoses into endosomes. We treated cells with EGF in the presence of AG-1478, a specific EGFR tyrosine kinase inhibitor, and monensin, which blocks the recycling of EGFR. This treatment led to the internalization of nonactivated EGF-EGFR complexes into endosomes. The endosome-associated EGFR was then activated by removing AG-1478 and monensin. During this procedure we did not observe any surface EGFR phosphorylation. We also achieved specific activation of endosome-associated EGFR without using monensin. By using this system, we provided original evidence demonstrating that (i) the endosome can serve as a nucleation site for the formation of signaling complexes, (ii) endosomal EGFR signaling is sufficient to activate the major signaling pathways leading to cell proliferation and survival, and (iii) endosomal EGFR signaling is sufficient to suppress apoptosis induced by serum withdrawal.

Introduction One of the main reasons for disease recurrence in the curative breast cancer treatment setting is the development of drug resistance. Microtubule targeted agents (MTAs) are among the most commonly used drugs for the treatment of breaset cancer and therefore overcoming taxane resistance is of primary clinical importance. Our group has previously demonstrated that the microtubule dynamics of docetaxel-resistant MCF-7TXT cells are insensitivity to docetaxel due to the distinct expression profiles of β-tubulin isotypes in addition to the high expression of p-glycoprotein (ABCB1). In the present investigation we examined whether taxane-resistant breast cancer cells are more sensitive to microtubule destabilizing agents including vinca alkaloids and colchicine-site binding agents (CSBAs) than the non-resistant cells. Methods Two isogenic MCF-7 breast cancer cell lines were selected for resistance to docetaxel (MCF-7TXT) and the wild type parental cell line (MCF-7CC) to examine if taxane-resistant breast cancer cells are sensitive to microtubule-destabilizing agents including vinca alkaloids and CSBAs. Cytotoxicity assays, immunoblotting, indirect immunofluorescence and live imaging were used to study drug resistance, apoptosis, mitotic arrest, microtubule formation, and microtubule dynamics. Results MCF-7TXT cells were demonstrated to be cross resistant to vinca alkaloids, but were more sensitive to treatment with colchicine compared to parental non-resistant MCF-7CC cells. Cytotoxicity assays indicated that the IC50 of MCF-7TXT cell to vinorelbine and vinblastine was more than 6 and 3 times higher, respectively, than that of MCF-7CC cells. By contrast, the IC50 of MCF-7TXT cell for colchincine was 4 times lower than that of MCF-7CC cells. Indirect immunofluorescence showed that all MTAs induced the disorganization of microtubules and the chromatin morphology and interestingly each with a unique pattern. In terms of microtubule and chromain morphology, MCF-7TXT cells were more resistant to vinorelbine and vinblastine, but more sensitive to colchicine compared to MCF-7CC cells. PARP cleavage assay further demonstrated that all of the MTAs induced apoptosis of the MCF-7 cells. However, again, MCF-7TXT cells were more resistant to vinorelbine and vinblastine, and more sensitive to colchicine compared to MCF-7CC cells. Live imaging demonstrated that the microtubule dynamics of MCF-7TXT cells were less sensitive to vinca alkaloids, and more sensitive to colchicine. MCF-7TXT cells were also noted to be more sensitive to other CSBAs including 2MeOE2, ABT-751 and phosphorylated combretastatin A-4 (CA-4P). Conclusion Docetaxel-resistant MCF-7TXT cells have demonstrated cross-resistance to vinca alkaloids, but appear to be more sensitive to CSBAs (colchicine, 2MeOE2, ABT-751 and CA-4P) compared to non-resistant MCF-7CC cells. Taken together these results suggest that CSBAs should be evaluated further in the treatment of taxane resistant breast cancer.

The Epidermal Growth Factor Receptor (EGFR)-mediated signaling cascades have been intensely studied, especially as to how they relate to many cancers. It has been proposed that the G0 to S interval is the only portion of the cell cycle regulated by the EGF, and that the activation of the EGFR is inhibited during mitosis (M-phase) so to preserve energy needs required for mitotic structural changes. Here we show that all the major tyrosine residues in the EGFR C-terminus that are phosphorylated in interphase are also phosphorylated in nocodazole-induced M-phase in response to EGF, indicating full activation of EGFR. We further studied EGF-induced activation of downstream signaling pathways in M-phase in comparison to interphase. Some signaling proteins such as PLC-γ1 and CBL are strongly phosphorylated in M-phase. While two isoforms of AKT were phosphorylated in interphase, only the AKT2 isoform was phosphorylated in M-phase. p38 MAPK was constitutively phosphorylated in M-phase regardless of EGF stimulatio...

Background Chemoresistance is a major factor involved in a poor response and reduced overall survival in patients with advanced breast cancer. Although extensive studies have been carried out to understand the mechanisms of chemoresistance, many questions remain unanswered. Methods In this research, we used two isogenic MCF-7 breast cancer cell lines selected for resistance to doxorubicin (MCF-7DOX) or docetaxel (MCF-7TXT) and the wild type parental cell line (MCF-7CC) to study mechanisms underlying acquired resistance to taxanes in MCF-7TXT cells. Cytotoxicity assay, immunoblotting, indirect immunofluorescence and live imaging were used to study the drug resistance, the expression levels of drug transporters and various tubulin isoforms, apoptosis, microtubule formation, and microtubule dynamics. Results MCF-7TXT cells were cross resistant to paclitaxel, but not to doxorubicin. MCF-7DOX cells were not cross-resistant to taxanes. We also showed that multiple mechanisms are involved in the resistance to taxanes in MCF-7TXT cells. Firstly, MCF-7TXT cells express higher level of ABCB1. Secondly, the microtubule dynamics of MCF-7TXT cells are weak and insensitive to the docetaxel treatment, which may partially explain why docetaxel is less effective in inducing M-phase arrest and apoptosis in MCF-7TXT cells in comparison with MCF-7CC cells. Moreover, MCF-7TXT cells express relatively higher levels of β2- and β4-tubulin and relatively lower levels of β3-tubulin than both MCF-7CC and MCF-7DOX cells. The subcellular localization of various β-tubulin isoforms in MCF-7TXT cells is also different from that in MCF-7CC and MCF-7DOX cells. Conclusion Multiple mechanisms are involved in the resistance to taxanes in MCF-7TXT cells. The high expression level of ABCB1, the specific composition and localization of β-tubulin isoforms, the weak microtubule dynamics and its insensitivity to docetaxel may all contribute to the acquired resistance of MCF-7TXT cells to taxanes.

The cytotoxicity of Taxol represents both inhibition of cell proliferation and cell death. The drug blocked cells in the G2/M phase of the cell cycle. It has also been reported that Taxol induced cell apoptosis; however, the mode of action of Taxol is far from clear. In this communication, the cytotoxicity of Taxol in various breast cancer cell lines was carefully examined. We showed that Taxol treatment induced a biphasic decrease of viable cells. While the first phase of decrease occurred over concentrations ranging from 0.005 to 0.05 microM and the second phase of decrease occurred at concentrations ranging from 5 to 50 microM, there was a plateau between these ranges. We determined that the biphasic response was due to two different mechanisms. In the lower concentration range (0.005-0.05 microM), Taxol stabilized the spindle during mitosis, thereby blocking mitosis. This mitotic block led to the inhibition of cell proliferation and the induction of apoptosis. In the higher concentration range (5-50 microM), Taxol mainly increased the polymerization of microtubule and stimulated the formation of microtubule bundles, which blocked entry into S phase. This inhibition of S phase entry led to the inhibition of cell proliferation and the induction of necrosis. These findings may have profound clinical implications.