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Drug resistance is a major problem in cancer therapy with cisplatin. It has not been reported that pleiotrophin, which is anti-apoptotic in some cancer cells, is associated with cisplatin resistance. Pleiotrophin was exogenously expressed in 293 cells. Viability and apoptosis of PC3 cells treated with different concentrations of cisplatin in the presence or absence of purified pleiotrophin were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry, respectively. PC3 cells transfected with shRNAs were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and western blotting 24 h after transfection. MTT assay data indicated that the EC50 value of cisplatin for PC3 cells was significantly increased in the presence of pleiotrophin. Flow cytometry data demonstrated the pleiotrophin dose-dependent anti-apoptosis in PC3 cells treated with cisplatin. Knockdown of pleiotrophin with sh-RNA, as justified by RT-PCR and western blotting analysis, led to increased cisplatin induced-apoptosis in PC3 cells with an increased level of the cleaved poly ADP-ribose polymerase protein. Pleiotrophin may be a potential antiapoptotic protein associated with cisplatin susceptibility, which warrants further study on the role of pleiotrophin in cisplatin resistance., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

This study aims to explore and evaluate the antitumor efficacy of doxorubicin (DOX)-loaded liposomes containing the novel tri-block polymer folate-poly (2-ethyl-2-oxazoline)-distearoyl phosphatidyl ethanolamine (F-PEOz-DSPE), compared with folate-polyethylene glycol-distearoyl phosphatidyl ethanolamine (F-PEG-DSPE) to offer an alternative for PEG decorated carriers. PEOz, a pH-sensitive polymer, exhibits similar solubility and segmental flexibility to PEG. In our previous study, PEOz was employed to an F-PEOz-DSPE which was segmentally similar to F-PEG-DSPE and exhibited selective targeting and pH-sensitivity in tumor cells. In this work, DOX-loaded liposomes containing F-PEOz-DSPE (F-PEOz liposome) or F-PEG-DSPE (F-PEG liposome) were prepared. In vivo/vitro antitumor efficacy and biodistribution were compared between the two liposomes. F-PEOz liposome showed higher in vitro antitumor activity and significantly stronger inhibition of tumor growth in HeLa tumor-bearing nude mice (tumor inhibition rate, 81.20 vs 52.99% with the treatment of 9 mg/kg DOX-loaded F-PEOz liposome/F-PEG liposome) and much less toxicity than free DOX. In vivo fluorescence imaging experiment confirmed that F-PEOz liposome accumulated much more than F-PEG liposome in tumor. Based on the above, F-PEOz liposome may be a promising carrier in tumor chemotherapy to achieve better therapeutic efficacy.

Cancer stem cells (CSCs) play pivotal roles in cancer metastasis, and strategies targeting cancer stemness may greatly reduce cancer metastasis and improve patients' survival. The canonical Wnt/β-catenin pathway plays critical roles in CSC generation and maintenance as well as in normal stem cells. Non-specifically suppressing the Wnt/β-catenin pathway for cancer therapy could be deleterious to normal cells. To achieve specific β-catenin attenuation in cancer cells, we report an integrin α5 (ITGA5)-targeting nanoparticle for treating metastatic triple negative breast cancer (TNBC). We found that ITGA5 is highly expressed in strongly migratory and invasive TNBC cells as well as their lung metastatic foci, which rationalizes active-targeted drug delivery to TNBC cells via ITGA5 ligands such as a commercialized ligand-RGD motif (Arg-Gly-Asp). We modified lipid-polymer hybrid (LPH) nanoparticle for TNBC-targeted delivery of diacidic norcantharidin (NCTD), a potent anti-cancer compound but with short half-life. Notably, in vivo imaging analysis showed that RGD-decorated LPH (RGD-LPH) accumulated more significantly and remained much longer than LPH in nude mouse orthotopic mammary TNBC tumor and lung metastatic tumor, which implicated the feasibility of ITGA5-targeting strategy for treating metastatic TNBC. Moreover, systemic administration of NCTD-loaded RGD-LPH (RGD-LPH-NCTD) reduced nude mouse orthotopic mammary TNBC tumor growth and metastasis more effectively than free NCTD and LPH-NCTD via down-regulating β-catenin. These findings suggest that ITGA5-targeting nanoparticles may provide a facil and unique strategy of specially attenuating β-catenin in vivo for treating metastatic TNBC., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Because of the insolubility of miriplatin in water, miriplatin and lipiodol suspension is the sole formulation of miriplatin approved in Japan to treat hepatocellular carcinoma by transcatheter arterial chemoembolization. Until now, there have been no reports of other pharmaceutical formulations of miriplatin except miriplatin/lipiodol suspension. In this study, we aimed not only to develop miriplatin-loaded liposomes (lipomiriplatins) which could be administrated systematically for tumors besides hepatocellular carcinoma but also to ascertain whether miriplatin, like its analog of NDDP, was a liposome-dependent antitumor agent. We found that miriplatin could be successfully incorporated into liposomes, and both the stability and antitumor activity of lipomiriplatins were independent of the liposomal compositions. Especially, HPLC was successfully established as the quantitative method for lipomiriplatins, which completely eliminated the interference of cholesterol. Lipomiriplatins possessed favorable colloidal properties (99.71 ± 0.56 nm, -50 mV), high drug-loading capacity (about 2.2 mg/mL), excellent entrapment efficiency (>95%), and robust stability. The remarkable antitumor activities of lipomiriplatin were proved to be mediated by inducing cell apoptosis and were comparable to that of the commercial cisplatin and oxaliplatin injections, indicating that lipomiriplatins showed great promise for future potential clinical application via systematic administration., (Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.)

Pancreatic ductal adenocarcinoma (PDAC) elicits a dense stromal response that blocks vascular access because of pericyte coverage of vascular fenestrations. In this way, the PDAC stroma contributes to chemotherapy resistance, and the small-sized nanocarrier loaded with platinum has been adopted to address this problem which is not suitable for loading docetaxel (DTX). In the present study, we used the poly(D,L-lactide)-b-polyethylene glycol-methoxy (mPEG-b-PDLLA) to encapsulate DTX and got a small-sized polymeric micelle (SPM); meanwhile we functionalized the SPM's surface with TAT peptide (TAT-PM) for a higher permeability. The diameters of both SPM and TAT-PM were in the range of 15-26 nm. In vitro experiments demonstrated that TAT-PM inhibited Capan-2 Luc PDAC cells growth more efficiently and induced more apoptosis compared to SPM and Duopafei. The in vivo therapeutic efficiencies of SPM and TAT-PM compared to free DTX was investigated on the orthotopic transplantation model of Capan-2 Luc. SPM exerted better therapeutic efficiency than free DTX, however, TAT-PM didn't outperformed SPM. Overall, these results disclosed that SPM could represent a new therapeutic approach against pancreatic cancer, but its permeability to PDAC was not the only decisive factor.

Background: The small size of ultra-small nanoparticles makes them suitable for lymphatic delivery, and many recent studies have examined their role in anti-metastasis therapy. However, the anti-metastatic efficacy of small-sized nanocarriers loaded with taxanes such as docetaxel has not yet been investigated in malignant breast cancer., Methods: We encapsulated docetaxel using poly(D,L-lactide)1300-b-(polyethylene glycol-methoxy)2000 (mPEG2000-b-PDLLA1300) to construct polymeric micelles with a mean diameter of 16.76 nm (SPM). Patient-like 4T1/4T1luc breast cancer models in Balb/c mice, with resected and unresected primary tumors, were used to compare the therapeutic efficacies of SPM and free docetaxel (Duopafei) against breast cancer metastasis using bioluminescent imaging, lung nodule examination, and histological examination., Result: SPM showed similar efficacy to Duopafei in terms of growth suppression of primary tumors, but greater chemotherapeutic efficacy against breast cancer metastasis. In addition, lung tissue inflammation was decreased in the SPM-treated group, while many tumor cells and neutrophils were found in the Duopafei-treated group., Conclusion: Small-sized mPEG2000-b-PDLLA1300 micelles could provide an enhanced method of docetaxel delivery in breast cancer metastasis, and may represent a valid chemotherapeutic strategy in breast cancer patients with resected primary tumors.

Recently, survivin has been attracting great attention because it plays an important role in inhibiting the apoptosis process of tumor cells. Down-regulating the expression of survivin gene by small interfering RNA (siRNA) offers a promising method for anti-tumor therapy. However, lack of appropriate siRNA delivery vector has significantly hindered the successful application of survivin-targeted siRNA in anti-tumor therapy. The purpose of this study was to use polysaccharide vector TAT-g-CS we synthesized to deliver functional siRNA and evaluate its in vivo anti-tumor activity. TAT-g-CS vector was firstly synthesized and well structurally characterized. MTT assay showed that TAT-g-CS vector exhibited good biocompatibility. TAT-g-CS complexed with siRNA offering nanoparticles with an average particle size of 212.2 nm and a polydispersity index of 0.121, and the zeta potential of the nanoparticles was +18.58 mV. Results from reporter gene assay suggested that luciferase-targeted siRNA when delivered by TAT-g-CS could down-regulate the expression of luciferase gene with 75.3% reduction. Most importantly, we use siRNA(Sur) targeting survivin gene to assess the in vitro and in vivo delivery capacity of TAT-g-CS and its anti-tumor effects. Our results demonstrated that TAT-g-CS/siRNA(Sur) nanoparticles not only strongly inhibited the in vitro proliferation of 4T1-Luc tumor cells via inducing cell apoptosis, but also effectively inhibited the in vivo growth and metastasis of malignant breast tumor, which suggested that TAT-g-CS/siRNA nanoparticle was a highly efficient non-viral system for siRNA delivery, especially for anti-tumor therapy based on siRNA therapeutics., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Docetaxel (DTX) is hydrophobic, and its available formulations (Taxotere(®) & Duopafei(®)) require Tween80 and ethanol vehicle to allow parental administration. DTX-loaded poly(D,L-lactide)-b-polyethylene glycol-methoxy (mPEG-b-PDLLA) polymeric micelle (PM) is a Tween80-free formulation of DTX, which has been extensively studied but rarely involved with industrialization issues. In this work, novel DTX-PM with improved loading capacity and well-reconsitution ability was developed. The freeze-dried DTX-PM was analyzed by HPLC, transmission electron microscopy (TEM) and dynamic light scattering (DLS) to determine the DTX loading, micelle morphology and size respectively. The in vitro cytotoxic activity of DTX-PM in 4T1 cells was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the corresponding in vivo study was assessed in BALB/c mice bearing 4T1 tumor through intravenous administration. The DTX-loading and efficiency into the micelles were 20.74±1.23% and 93.7±1.03% respectively, which was much higher than ever reported PM. The DTX-PM was spherical with a mean particle size of 16.62±0.31 nm, which suggested that they were able to selectively accumulate in solid tumors by enhanced permeability and retention (EPR) effect. Another important characteristic of DTX-PM is the long term storage and reuses as aqueous injection solution. Many kinds of lyoprotectants were also investigated and dextrose was found to an excellent one. Compared with Duopafei(®), DTX-PM showed better cytotoxicity and anti-metastasis ability against 4T1 cells in vitro and in vivo. In conclusion, DTX-PM significantly enhanced drug-loading capacity of DTX and had well-reconsitution ability, which could be a promising drug delivery system for clinic.

Vinigrol is a natural diterpenoid with unprecedented chemical structure, driving great efforts into its total synthesis in the past decades. Despite anti-hypertension and anti-clot ever reported, comprehensive investigations on bioactions and molecular mechanisms of Vinigrol are entirely missing. Here we firstly carried out a complete functional prediction of Vinigrol using a transcriptome-based strategy coupled with multiple bioinformatic analyses and identified "anti-cancer" as the most prominent biofunction ahead of anti-hypertension and anti-depression/psychosis. Broad cytotoxicity was subsequently confirmed on multiple cancer types. Further mechanistic investigation on several breast cancer cells revealed that its anti-cancer effect was mainly through activating PERK/eIF2α arm of unfolded protein response (UPR) and subsequent non-apoptotic cell death independent of caspase activities. The other two branches of UPR, IRE1α and ATF6, were functionally irrelevant to Vinigrol-induced cell death. Using CRISPR/Cas9-based gene activation, repression, and knockout systems, we identified the essential contribution of ATF4 and DDIT3, not ATF6, to the death process. This study unraveled a broad anti-cancer function of Vinigrol and its underlying targets and regulatory mechanisms. It paved the way for further inspection on the structure-efficacy relationship of the whole compound family, making them a novel cluster of PERK-specific stress activators for experimental and clinical uses. [Display omitted] • Chemical transcriptome allows for unbiased bioactivity prediction of Vinigrol. • Vinigrol exerts broad anti-cancer with mild toxicity to normal cells. • Vinigrol induces non-apoptotic cell death independent of caspases. • Activation of PERK, not IRE1α and ATF6 arm of UPR promotes the anti-cancer effect. • CRISPR systems pinpointed ATF4/DDIT3 not ATF6 as essential death mediators. [ABSTRACT FROM AUTHOR]

Hypofractionated radiotherapy (HFRT) or chemotherapy combined with programmed death-1 (PD-1) blockade has achieved good clinical control in advanced nonsmall cell lung cancer (NSCLC). However, the relative influence of HFRT + PD-1 blockade and chemo-immunotherapy on peripheral memory T cell subsets in NSCLC responders has not been evaluated in clinical practice. Thirty-nine patients with advanced NSCLC were enrolled. The frequencies of naive (Tn; CD45RA+CCR7+), central memory (Tcm; CD45RA–CCR7+), effector memory (Tem; CD45RA–CCR7–), and effector memory RA (TemRA; CD45RA+CCR7–) T cell subsets and PD-1 expression were analyzed in CD4+ and CD8+ T cells using flow cytometry from peripheral blood samples. The correlations of memory T cell subsets and PD-1 expression with overall survival in HFRT + PD-1 blockade group were examined using the Kaplan–Meier method. Patients with partial response to HFRT + PD-1 blockade showed reduction in Tn and expansion in TemRA cell subpopulations among CD8+ T cells and reduced PD-1+CD4+ and PD-1+CD8+ T cells, all of which were significantly correlated with overall survival. The responders to chemo-immunotherapy showed expansion of the TemRA and decrease of Tcm in CD8+ T cell subpopulation. Our findings show that HFRT+PD-1 blockade and chemo-immunotherapy combination therapies induce differential memory T cell subset differentiation, offering predictive markers for treatment response. Clinical Trial Information: https://clinicaltrials.gov/ct2/show/ChiCTR-1900027768. [ABSTRACT FROM AUTHOR]

Abstract: We studied copper-free Sonogashira reaction using 7-chloro camptothecins, and determined that rac-BINAP/Pd(OAc)2 was an efficient catalyst for the coupling reaction. With this process, a number of 7-substituted camptothecins with a wide range of functional groups are potentially accessible. Besides, two drugs, SN-38 and BNP-1350, could be prepared by this method. [Copyright &y& Elsevier]