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1.
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Background

Tyro3, Axl, and Mertk (TAMs) are a family of three conserved receptor tyrosine kinases that have pleiotropic roles in innate immunity and homeostasis and when overexpressed in cancer cells can drive tumorigenesis.

Methods

In the present study, we engineered EGFR/TAM chimeric receptors (EGFR/Tyro3, EGFR/Axl, and EGF/Mertk) with the goals to interrogate post-receptor functions of TAMs, and query whether TAMs have unique or overlapping post-receptor activation profiles. Stable expression of EGFR/TAMs in EGFR-deficient CHO cells afforded robust EGF inducible TAM receptor phosphorylation and activation of downstream signaling.

Results

Using a series of unbiased screening approaches, that include kinome-view analysis, phosphor-arrays, RNAseq/GSEA analysis, as well as cell biological and in vivo readouts, we provide evidence that each TAM has unique post-receptor signaling platforms and identify an intrinsic role for Axl that impinges on cell motility and invasion compared to Tyro3 and Mertk.

Conclusion

These studies demonstrate that TAM show unique post-receptor signatures that impinge on distinct gene expression profiles and tumorigenic outcomes.
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3.

Background

Knockdown of Akt1 promotes Epithelial-to-Mesenchymal Transition in breast cancer cells. However, the mechanisms are not completely understood.

Methods

Western blotting, immunofluorescence, luciferase assay, real time PCR, ELISA and Matrigel invasion assay were used to investigate how Akt1 inhibition promotes breast cancer cell invasion in vitro. Mouse model of lung metastasis was used to measure in vivo efficacy of Akt inhibitor MK2206 and its combination with Gefitinib.

Results

Knockdown of Akt1 stimulated β-catenin nuclear accumulation, resulting in breast cancer cell invasion. β-catenin nuclear accumulation induced by Akt1 inhibition depended on the prolonged activation of EGFR signaling pathway in breast cancer cells. Mechanistic experiments documented that knockdown of Akt1 inactivates PIKfyve via dephosphorylating of PIKfyve at Ser318 site, resulting in a decreased degradation of EGFR signaling pathway. Inhibition of Akt1 using MK2206 could induce an increase in the expression of EGFR and β-catenin in breast cancer cells. In addition, MK2206 at a low dosage enhance breast cancer metastasis in a mouse model of lung metastasis, while an inhibitor of EGFR tyrosine kinase Gefitinib could potentially suppress breast cancer metastasis induced by Akt1 inhibition.

Conclusion

EGFR-mediated β-catenin nuclear accumulation is critical for Akt1 inhibition-induced breast cancer metastasis.
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4.

Objectives

Copper oxide nanoparticles (CuO NPs) promoting anticancer activity may be due to the regulation of various classes of histone deacetylases (HDACs).

Results

Green-synthesized CuO NPs significantly arrested total HDAC level and also suppressed class I, II and IV HDACs mRNA expression in A549 cells. A549 cells treated with CuO NPs downregulated oncogenes and upregulated tumor suppressor protein expression. CuO NPs positively regulated both mitochondrial and death receptor-mediated apoptosis caspase cascade pathway in A549 cells.

Conclusion

Green-synthesized CuO NPs inhibited HDAC and therefore shown apoptosis mediated anticancer activity in A549 lung cancer cell line.
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5.

Objectives

To examine the potential of ferulic acid and 4-vinylguaiacol for inhibiting epidermal growth factor receptor (EGFR) in human breast cancer cells in vitro.

Results

Ferulic acid and 4-vinylguaiacol limit the EGF (epidermal growth factor)-induced breast cancer proliferation and new DNA synthesis. Western blot analysis revealed both ferulic acid and 4-vinylguaiacol exhibit sustained inhibition of EGFR activation through down-regulation of Tyr 1068 autophosphorylation. Molecular docking analysis shows ferulic acid forming hydrogen bond interaction with Lys 745 and Met 793 whereas, 4-vinylguaiacol forms two hydrogen bonds with Phe 856 and exhibits stronger hydrophobic interactions with multiple amino acid residues at the EGFR kinase domain.

Conclusions

Ferulic acid and 4-vinylguaiacol could serve as a potential structure for the development of new small molecule therapeutics against EGFR.
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6.

Background

The heterogeneity of response to treatment in patients with glioblastoma multiforme suggests that the optimal therapeutic approach incorporates an individualized assessment of expected lesion progression. In this work, we develop a novel computational model for the proliferation and necrosis of glioblastoma multiforme.

Methods

The model parameters are selected based on the magnetic resonance imaging features of each tumor, and the proposed technique accounts for intrinsic cell division, tumor cell migration along white matter tracts, as well as central tumor necrosis. As a validation of this approach, tumor growth is simulated in the brain of a healthy adult volunteer using parameters derived from the imaging of a patient with glioblastoma multiforme. A mutual information metric is calculated between the simulated tumor profile and observed tumor.

Results

The tumor progression profile generated by the proposed model is compared with those produced by existing models and with the actual observed tumor progression. Both qualitative and quantitative analyses show that the model introduced in this work replicates the observed progression of glioblastoma more accurately relative to prior techniques.

Conclusions

This image-driven model generates improved tumor progression profiles and may contribute to the development of more reliable prognostic estimates in patients with glioblastoma multiforme.
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7.

Background

Genomic instability is a hallmark of cancer cells, and this cellular phenomenon can emerge as a result of replicative stress. It is possible to take advantage of replicative stress, and enhance it in a targeted way to fight cancer cells. One of such strategies involves targeting the cell division cycle 7-related protein kinase (CDC7), a protein with key roles in regulation of initiation of DNA replication. CDC7 overexpression is present in different cancers, and small molecule inhibitors of the CDC7 have well-documented anti-tumor effects. Here, we aimed to test the potential of CDC7 inhibition as a new strategy for glioblastoma treatment.

Methods

PHA-767491 hydrochloride was used as the CDC7 inhibitor. Two glioblastoma cell lines (U87-MG and U251-MG) and a control cell line (3T3) were used to characterize the effects of CDC7 inhibition. The effect of CDC7 inhibition on cell viability, cell proliferation, apoptosis, migration, and invasion were analyzed. In addition, real-time PCR arrays were used to identify the differentially expressed genes in response to CDC7 inhibition.

Results

Our results showed that CDC7 inhibition reduces glioblastoma cell viability, suppresses cell proliferation, and triggers apoptosis in glioblastoma cell lines. In addition, we determined that CDC7 inhibition also suppresses glioblastoma cell migration and invasion. To identify molecular targets of CDC7 inhibition, we used real-time PCR arrays, which showed dysregulation of several mRNAs and miRNAs.

Conclusions

Taken together, our findings suggest that CDC7 inhibition is a promising strategy for treatment of glioblastoma.
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8.

Objectives

To investigate the biological functions of microRNA-144-3p with respect to proliferation and apoptosis of human salivary adenoid carcinoma cell lines via mTOR.

Results

After transfection of microRNA-144-3p agomir, cell viability assays confirmed that the salivary adenoid carcinoma cell (SACC) proliferation was inhibited and apoptosis was induced. Dual luciferase reporter assay validated that the mammalian target of rapamycin (mTOR) was a direct target of miR-144-3p. Western blot, immunofluorescent analysis and a xenograft mouse model of adenoid cystic carcinoma indicated that miR-144-3p was a tumor suppressor and repressed mTOR expression and signaling in SACCs.

Conclusions

MicroRNA-144-3p inhibits proliferation and induces apoptosis of human salivary adenoid carcinoma cells by downregulating mTOR expression in vitro and in vivo.
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9.

Background

Glioblastoma multiforme, the most prevalent and aggressive brain tumour, has a poor prognosis. The molecular mechanisms underlying gliomagenesis remain poorly understood. Therefore, molecular research, including various markers, is necessary to understand the occurrence and development of glioma.

Method

Weighted gene co-expression network analysis (WGCNA) was performed to construct a gene co-expression network in TCGA glioblastoma samples. Gene ontology (GO) and pathway-enrichment analysis were used to identify significance of gene modules. Cox proportional hazards regression model was used to predict outcome of glioblastoma patients.

Results

We performed weighted gene co-expression network analysis (WGCNA) and identified a gene module (yellow module) related to the survival time of TCGA glioblastoma samples. Then, 228 hub genes were calculated based on gene significance (GS) and module significance (MS). Four genes (OSMR + SOX21?+?MED10?+?PTPRN) were selected to construct a Cox proportional hazards regression model with high accuracy (AUC?=?0.905). The prognostic value of the Cox proportional hazards regression model was also confirmed in GSE16011 dataset (GBM: n?=?156).

Conclusion

We developed a promising mRNA signature for estimating overall survival in glioblastoma patients.
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10.

Objectives

To evaluate the effects of dexamethasone on the aging of mesenchymal stem cells from human gingiva using next-generation sequencing.

Results

Four mRNAs were upregulated and 12 were downregulated when the results of dexamethasone at 24 h were compared with the control at 24 h. Expressions of SIRT1 and IL6 were decreased in dexamethasone at 24 h but expression of EDN1 was increased.

Conclusions

Application of dexamethasone reduced the expression of SIRT1 and IL6 but enhanced the expression of EDN1 of stem cells.
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11.

Objective

To measure clusterin expression in pancreatic cancer tissues and cell lines and to evaluate whether clusterin confers resistance to gmcitabine in pancreatic cancer cells.

Methods

Immunohistochemistry for clusterin was performed on 50 primary pancreatic cancer tissues and 25 matched backgrounds, and clusterin expression in 5 pancreatic cancer cell lines was quantified by Western blot and PT-PCR. The correlation between clusterin expression level and gmcitabine IC50 in pancreatic cancer cell lines was evaluated. The effect of an antisense oligonucleotide (ASO) against clusterin(OGX-011) on gmcitabine resistance was evaluated by MTT assays. Xenograft model was used to demonstrate tumor growth.

Results

Pancreatic cancer tissues expressed significantly higher levels of clusterin than did normal pancreatic tissues (P < 0.01). Clusterin expression levels were correlated with gmcitabine resistance in pancreatic cancer cell lines, and OGX-011 significantly decreased BxPc-3 cells resistance to gmcitabine (P < 0.01). In vivo systemic administration of AS clusterin and gmcitabine significantly decreased the s.c. BxPC-3 tumor volume compared with mismatch control ODN plus gmcitabine.

Conclusion

Our finding that clusterin expression was significantly higher in pancreatic cancer than in normal pancreatic tissues suggests that clusterin may confer gmcitabine resistance in pancreatic cancer cells.
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12.
13.

Objectives

To investigate the roles of miR-149 in the progression of human osteosarcoma (OS).

Results

miR-149 level was upregulated in tissues from OS patients more than in normal subjects. Cell proliferation and apoptosis assays revealed that miR-149 increased cell proliferation and inhibited cell apoptosis in OS cell line (MG63). An increase of Bcl-2 gene expression and a decrease of cleaved-caspase-3, and cleaved-PARP expression were observed in MG63 cells with transfection of miR-149. Additionally, bone morphogenetic protein 9 (BMP9) was identified as a target of miR-149 in MG63 cells, and BMP9 expression was negatively correlated with miR149 level in OS clinical samples. Co-overexpression of BMP9 with miR-149 in MG63 cells prohibited miR-149-mediated promotive effects on OS progression. Importantly, overexpression of miR-149 conferred chemoresistance in MG63 cells.

Conclusions

miR-149 promotes OS progression via targeting BMP9.
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14.

Background

RAC3 coactivator overexpression has been implicated in tumorigenesis, contributing to inhibition of apoptosis and autophagy. Both mechanisms are involved in resistance to treatment with chemotherapeutic agents. The aim of this study was to investigate its role in chemoresistance of colorectal cancer.

Methods

The sensitivity to 5-fluorouracil and oxaliplatin in colon cancer cells HT-29, HCT 116 and Lovo cell lines, expressing high or low natural levels of RAC3, was investigated using viability assays.

Results

In HCT 116 cells, we found that although 5-fluorouracil was a poor inducer of apoptosis, autophagy was strongly induced, while oxaliplatin has shown a similar ability to induce both of them. However, in HCT 116 cells expressing a short hairpin RNA for RAC3, we found an increased sensitivity to both drugs if it is compared with control cells. 5-Fluorouracil and oxaliplatin treatment lead to an enhanced caspase 3-dependent apoptosis and produce an increase of autophagy. In addition, both process have shown to be trigged faster than in control cells, starting earlier after stimulation.

Conclusions

Our results suggest that RAC3 expression levels influence the sensitivity to chemotherapeutic drugs. Therefore, the knowledge of RAC3 expression levels in tumoral samples could be an important contribution to design new improved therapeutic strategies in the future.
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15.

Objectives

To investigate the potential of recombinant phytaspase loaded manganese (Mn) doped zinc sulphide (ZnS) quantum dots embedded chitosan nanoparticles for augmenting cisplatin induced chemotherapy of HeLa cells.

Results

The recombinant phytaspase was cloned into bacterial expression vector PGEX-4T-2. The expressed and purified recombinant plant phytaspase protein from Escherichia coli BL21 was immobilized onto the cationic nanocomposite. Confocal microscopy elucidated the delivery of these luminescent nanocomposites inside cervical cancer HeLa cells. A 50% reduction in the viability of HeLa cells was achieved only in the case of phytaspase–nanocomposites–cisplatin combination at a dose of phytaspase (42 nM), nanocomposites (56.3 μg/ml) and cisplatin (0.44 μg/ml).

Conclusion

Luminescent cationic nanocomposites were developed for intracellular delivery of recombinant phytaspase, which due to its caspase-like activity assisted in substantiating the chemotherapeutic activity of apoptosis inducing drug-cisplatin.
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16.

Background

The cell source for transplantation therapy is always a prerequisite question to be solved in clinical applications. Neural cells are considered non-regenerable, which highly restrict their application in the treatment for nerve injury. Therefore, neural trans-differentiation based on gene transfection provides a new solution to this issue. Compared to viral strategy, non-viral gene delivery systems are considered as a more promising way to achieve this aim. This study centers on a novel application of Porphyra yezoensis polysaccharide as a non-viral gene carrier for the neural trans-differentiation of mouse fibroblasts.

Results

Ethanediamine modified P. yezoensis polysaccharide (Ed-PYP) served as a gene carrier and a group of plasmids that encode Ascl1, Brn4, and Tcf3 (pABT) self-assembled into nanoparticles. Results demonstrated that Ed-PYP–pABT nanoparticles at Ed-PYP: pABT weight ratio of 40:1 was the optimal candidate for gene delivery. ELISA assay revealed the highest expression levels of NGF, BDNF and SHH at 14 days after last transfection. Immunofluorescence and western blot assays also showed robust expression of neural markers including Nestin, GFAP, β-3tubulin, NF200, GAP43 and MAP2, in induced 3T6 cells at this time point.

Conclusion

Overall, these findings indicated that the P. yezoensis polysaccharide-based non-viral gene co-delivery system is a promising strategy for the generation of neural cells, which might facilitate the developments in the recovery of neural injuries.
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17.

Introduction

Amphiphilic copolymer nanoparticle-encapsulated multi-target chemotherapeutic drugs have attracted considerable attention due to their favorable drug efficiency and potential application prospect. Studies have shown that an amphiphilic copolymer, methoxypoly(ethylene glycol)-poly(lactide-co-glycolide) modified with ε-polylysine, and encapsulated with hydrophilic doxorubicin, hydrophobic paclitaxel and survivin siRNA profoundly improved the therapeutic effect both in vitro and in vivo.

Objectives

To investigate how MCF-7 cells would response to the exposure of these nanoparticles over with time and assess the biological effects of these nanoparticles and their encapsulated drugs in a holistic manner.

Methods

MCF-7 cells were treated with PBS, nanocarrier and three encapsulated drugs, respectively. Metabolic alterations associated with nano-drugs exposure were investigated by performing untargeted NMR metabolomics with combination of targeted fatty acids analysis by GC-MS on cell extracts. Altered metabolic pathways were further validated by qRT-PCR approach.

Results

Copolymers showed great biocompatibility with cells as it induced transit metabolic disruptions without affecting cell survival rate. The rapid release of encapsulated doxorubicin resulted in inhibition of glycolysis and DNA synthesis, active proteolysis; these metabolic alternations were recovered after 10 h exposure. However, the combination use of multiple drugs consistently induced cell cycle arrest and apoptosis evidenced by reduction in glycolysis, active proteolysis, stimulated O-GlcNAcylation, reduced the PC:GPC ratio and fatty acids accumulation. Prolonged exposure to encapsulated-multiple-drugs also induced oxidative stress to cells.

Conclusion

These findings provide important insight into the biological effects of nanoparticles and their encapsulated drugs while demonstrate that metabolomics is a powerful approach to evaluate the biological effects of nano-drugs.
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18.

Background

Compared to the design of a traditional multi-radius (MR) total knee arthroplasty (TKA), the single-radius (SR) implant investigated has a fixed flexion/extension center of rotation. The biomechanical effectiveness of an SR for functional daily activities, i.e., sit-to-stand, is not well understood. The purpose of the study was to compare the biomechanics underlying functional performance of the sit-to-stand (STS) movement between the limbs containing an MR and an SR TKA of bilateral TKA participants.

Methods

Sagittal plane kinematics and kinetics, and EMG data for selected knee flexor and extensor muscles were analyzed for eight bilateral TKA patients, each with an SR and an MR TKA implant.

Results

Compared to the MR limb, the SR limb demonstrated greater peak antero-posterior (AP) ground reaction force, higher AP ground reaction impulse, less vastus lateralis and semitendinosus EMG during the forward-thrust phase of the STS movement. No significant difference of knee extensor moment was found between the two knees.

Conclusion

Some GRF and EMG differences were evident between the MR and SR limbs during STS movement. Compensatory adaptations may be used to perform the STS.
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19.
20.

Background

Human adipose-derived stem cells (hADSCs) are capable of differentiating into many cells such as cardiac cells. Different types of inducers are used for cardiac cell differentiation, but this question still remains to be investigated, which one is the best. The aim of this paper was to investigate the effect of combination of fibrin scaffold and trichostatin A (TSA), for differentiation of hADSCs into cardiomyocyte-like cells.

Methods

After approval of characteristics of hADSCs and fibrin scaffold, hADSCs were cultured in fibrin scaffold with 10 µM TSA for 72 h and kept in standard conditions for 4 weeks. QRT-PCR and immunostaining assay were performed for evaluating the expression pattern of special cardiac genes and proteins.

Results

In particular, our study showed that fibrin scaffold alongside TSA enhanced expression of the selected genes and proteins.

Conclusions

We concluded that the TSA alone or with fibrin scaffold can lead to the generation of cardiac like cells in a short period of time.
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