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Cembrane diterpenoids (cembranoids), characterized by a 14-membered carbon ring and wide variety of functional groups, found in marine and terrestrial organisms. Many studies have shown that cembrane diterpenoids have cytotoxic and anti-inflammatory activities and are widely used in the development of new drugs. This review covered publications from 2011 to 2022 and classified the cembrane-type diterpenoids into isopropyl (ene) type, γ-lactone or unsaturated five-membered ring, δ-lactone or unsaturated six-membered ring, ε-lactone or unsaturated seven-membered ring, and other cembrane diterpenes. In addition, the biological activity and structure-activity relationship were summarized. This will provide guidance for new cembrane-type diterpenes as lead compounds to explore their potential application for treating cancer and inflammatory diseases., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The cancer-associated fibroblast (CAF) barrier in pancreatic ductal adenocarcinoma (PDAC) greatly restricts clinical outcomes. Major obstacles to PDAC treatment include restricted immune cell infiltration and drug penetration and the immunosuppressive microenvironment. Here, we reported a "shooting fish in a barrel" strategy by preparing a lipid-polymer hybrid drug delivery system (PI/JGC/L-A) that could overcome the CAF barrier by turning it into a "barrel" with antitumor drug depot properties to alleviate the immunosuppressive microenvironment and increase immune cell infiltration. PI/JGC/L-A is composed of a pIL-12-loaded polymeric core (PI) and a JQ1 and gemcitabine elaidate coloaded liposomal shell (JGC/L-A) that has the ability to stimulate exosome secretion. By normalizing the CAF barrier to create a CAF "barrel" with JQ1, stimulating the secretion of gemcitabine-loaded exosomes from the CAF "barrel" to the deep tumor site, and leveraging the CAF "barrel" to secrete IL-12, PI/JGC/L-A realized effective drug delivery to the deep tumor site, activated antitumor immunity at the tumor site, and produced significant antitumor effects. In summary, our strategy of transforming the CAF barrier into antitumor drug depots represents a promising strategy against PDAC and might benefit the treatment of any tumors facing a drug delivery barrier.

In this study, 2-benzyl-10a-(1 H -pyrrol-2-yl)-2,3-dihydropyrazino[1,2- a ]indole-1,4,10(10a H )-trione (DHPITO), a previously identified inhibitor against hepatocellular carcinoma cells, is shown to exert its cytotoxic effects by suppressing the proliferation and growth of CRC cells. An investigation of its molecular mechanism confirmed that the cytotoxic activity of DHPITO is mediated through the targeting of microtubules with the promotion of subsequent microtubule polymerisation. With its microtubule-stabilising ability, DHPITO also consistently arrested the cell cycle of the CRC cells at the G2/M phase by promoting the phosphorylation of histone 3 and the accumulation of EB1 at the cell equator, reduced the levels of CRC cell migration and invasion, and induced cellular apoptosis. Furthermore, the compound could suppress both tumour size and tumour weight in a CRC xenograft model without any obvious side effects. Taken together, the findings of the present study reveal the antiproliferative and antitumour mechanisms through which DHPITO exerts its activity, indicating its potential as a putative chemotherapeutic agent and lead compound with a novel structure.

Protein tyrosine phosphatases function in dephosphorylating target proteins to regulate signaling pathways that control a broad spectrum of fundamental physiological and pathological processes. Detailed knowledge concerning the roles of classical PTPs in human cancer merits in-depth investigation. We comprehensively analyzed the regulatory mechanisms and clinical relevance of classical PTPs in more than 9000 tumor patients across 33 types of cancer. The independent datasets and functional experiments were employed to validate our findings. We exhibited the extensive dysregulation of classical PTPs and constructed the gene regulatory network in human cancer. Moreover, we characterized the correlation of classical PTPs with both drug-resistant and drug-sensitive responses to anti-cancer drugs. To evaluate the PTP activity in cancer prognosis, we generated a PTPscore based on the expression and hazard ratio of classical PTPs. Our study highlights the notable role of classical PTPs in cancer biology and provides novel intelligence to improve potential therapeutic strategies based on pTyr regulation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wang, Ba, Zhang, Zhang, Wang, Bai, Li, Zhao, Zhao, Yu and Wang.)

The development of inhibitors targeting the PI3K-Akt-mTOR signaling pathway has been greatly hindered by the on-target AEs, such as hyperglycemia and hepatotoxicities. In this study, a series of diaryl urea derivatives has been designed and synthesized based on clinical candidate gedatolisib (6aa), and most of the newly synthesized derivatives showed kinase inhibitory and antiproliferative activities within nanomolar and submicromolar level, respectively. The terminal l-prolineamide substituted derivative 6 ab showed 8.6-fold more potent PI3Kα inhibitory activity (0.7 nM) and 4.6-fold more potent antiproliferative effect against HCT116 cell lines (0.11 μM) compared with control 6aa. The potential antitumor mechanism and efficacy of 6 ab in HCT116 xenograft models have also been evaluated, and found 6 ab showed comparable in vivo antitumor activity with 6aa. The safety investigations revealed that compound 6 ab exhibited more safer profiles in the selectivity of liver cells (selectivity index: >6.6 vs 1.85) and blood glucose regulation than 6aa. In addition, the in vitro stability assays also indicated our developed compound 6 ab possessed good metabolic stabilities., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

Chloroethylnitrosoureas (CENUs) are an important family of chemotherapies in clinical treatment of cancers, which exert antitumor activity by inducing the formation of DNA interstrand crosslinks (dG-dC ICLs). However, the drug resistance mediated by O 6 -alkylguanine-DNA alkyltransferase (AGT) and absence of tumor-targeting ability largely decrease the antitumor efficacy of CENUs. In this study, we synthesized an azobenzene-based hypoxia-activated combi-nitrosourea prodrug, AzoBGNU, and evaluated its hypoxic selectivity and antitumor activity. The prodrug was composed of a CENU pharmacophore and an O 6 -benzylguanine (O 6 -BG) analog moiety masked by a N,N-dimethyl-4-(phenyldiazenyl)aniline segment as a hypoxia-activated trigger, which was designed to be selectively reduced via azo bond break in hypoxic tumor microenvironment, accompanied with releasing of an O 6 -BG analog to inhibit AGT and a chloroethylating agent to induce dG-dC ICLs. AzoBGNU exhibited significantly increased cytotoxicity and apoptosis-inducing ability toward DU145 cells under hypoxia compared with normoxia, indicating the hypoxia-responsiveness as expected. Predominant higher cytotoxicity was observed in the cells treated by AzoBGNU than those by traditional CENU chemotherapy ACNU and its combination with O 6 -BG. The levels of dG-dC ICLs in DU145 cells induced by AzoBGNU was remarkably enhanced under hypoxia, which was approximately 6-fold higher than those in the AzoBGNU-treated groups under normoxia and those in the ACNU-treated groups. The results demonstrated that azobenzene-based combi-nitrosourea prodrug possessed desirable tumor-hypoxia targeting ability and eliminated chemoresistance compared with the conventional CENUs., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Mitochondria are essential organelles that provide energy for mammalian cells and participate in multiple functions, such as signal transduction, cellular differentiation, and regulation of apoptosis. Compared with the mitochondria in somatic cells, oocyte mitochondria have an additional level of importance since they are required for germ cell maturation, dysfunction in which can lead to severe inherited disorders. Thus, a systematic proteomic profile of oocyte mitochondria is urgently needed to support the basic and clinical research, but the acquisition of such a profile has been hindered by the rarity of oocyte samples and technical challenges associated with capturing mitochondrial proteins from live oocytes. Here, in this work, using proximity labeling proteomics, we established a mitochondria-specific ascorbate peroxidase (APEX2) reaction in live GV-stage mouse oocytes and identified a total of 158 proteins in oocyte mitochondria. This proteome includes intrinsic mitochondrial structural and functional components involved in processes associated with "cellular respiration", "ATP metabolism", "mitochondrial transport", etc. In addition, mitochondrial proteome capture after oocyte exposure to the antitumor chemotherapeutic cisplatin revealed differential changes in the abundance of several oocyte-specific mitochondrial proteins. Our study provides the first description of a mammalian oocyte mitochondrial proteome of which we are aware, and further illustrates the dynamic shifts in protein abundance associated with chemotherapeutic agents., (© 2021. The Author(s).)

Twenty-nine 12 N-substituted aloperine derivatives were synthesized and screened for suppression on PD-L1 expression in H460 cells, as a continuation of our work. Systematic structural modifications led to the identification of compound 6b as the most active PD-L1 modulator. Compound 6b could significantly down-regulate both constitutive and inductive PD-L1 expression in NSCLC cells, and successively enhance the cytotoxicity of co-cultured T cells against tumor cells at the concentration of 20 μM. Also, it exhibited a moderate in vivo anticancer efficacy against Lewis tumor xenograft with a stable PK and safety profile. The mechanism study indicated that 6b mediated the degradation of PD-L1 through a proteasome pathway, rather than a lysosome route. These results provided the powerful information for cancer immunotherapy of aloperine derivatives with unique endocyclic skeleton by targeting PD-L1 to activate immune cells to kill cancer cells., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Two previously undescribed compounds, moranigrine A ( 1 ) and morusamine ( 2 ), along with 18 known compounds were isolated from the fruits of Morus nigra Linn. and structurally characterized using spectroscopic data and electronic circular dichroism analyses. All isolates were evaluated for their inhibitory effects on the 3-phosphoglycerate dehydrogenase (PHGDH) enzyme, which catalyzes the first committed step for the synthesis of glucose-derived serine and is associated with many kinds of cancers. Among these compounds, methyl caffeate ( 3 ) exhibited effective inhibition against PHGDH and was directly bound to PHGDH based on the microscale thermophoresis method and the cellular thermal shift assay. Further biochemical assays revealed that 3 was a noncompetitive inhibitor with respect to the substrate of 3-phosphoglycerate and exhibited a concentration-dependent inhibition. Molecular docking demonstrated that 3 coordinated in an allosteric site of PHGDH with low binding energy. Meanwhile, 3 was selectively toxic to high PHGDH-expressing cancer cell lines and could cause apoptosis of cervical cancer cells in micromolar concentrations and could obviously inhibit tumor growth in the HeLa xenograft mouse model with low toxicities. Therefore, 3 could be developed as a potential inhibitor of PHGDH for the treatment of cancers. Our present study provides information about M. nigra as a functional food or pharmaceutical supplement in the application of cancer prevention and treatment.

Background and Aim: Chemotherapy drugs do not work well in esophageal squamous cell carcinoma (ESCC), and none of the targeted drugs have been applied in clinic. This study aims to identify effective targeted drugs and related biomarkers for the treatment of ESCC., Methods: The effect of 40 Food and Drug Administration-approved small-molecule inhibitors was first tested in five ESCC cell lines. CCK8 assays and xenografts derived from ESCC cell lines were performed to evaluate the anti-ESCC effects of inhibitors or chemotherapeutic agents in vitro and in vivo, respectively. Immunohistochemistry was utilized to analyze the p-EGFR expression in tissues. Western blot combining with gray analysis was conducted to detect the expression of interest protein. Flow cytometry and immunofluorescence assay were used to analyze apoptosis, cell cycle, and mitotic changes after drug treatment., Results: Afatinib showed remarkable effects on inhibiting ESCC cells with higher expression of p-EGFR. Results from combinatorial screening in ESCC cells expressing lower phosphorylation level of EGFR showed that paclitaxel and afatinib presented a significant synergistic inhibitory effect (P < 0.001). Molecular analysis revealed that paclitaxel sensitized afatinib by activating EGFR, and afatinib in combination with paclitaxel effectively blocked MAPK pathway and induced G2/M cell arrest and apoptosis that is an indicator of mitotic catastrophe., Conclusions: Our data demonstrate that afatinib is an effective drug for patients with ESCC expressing higher phosphorylation level of EGFR. And for patients with lower p-EGFR in tumors, paclitaxel in combination with afatinib might be a promising therapeutic strategy in ESCC., (© 2021 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

Objective: Kidney renal clear cell carcinoma (KIRC) is a common cancer with high morbidity and mortality in renal cancer. Thus, the transcriptome data of KIRC patients in The Cancer Genome Atlas (TCGA) database were analyzed and drug candidates for the treatment of KIRC were explored through the connectivity map (CMap) database., Methods: The transcriptome data of KIRC patients were downloaded from TCGA database, and KIRC-associated hub genes were screened out through differential analysis and protein-protein interaction (PPI) network analysis. Afterward, the CMap database was used to select drug candidates for KIRC treatment, and the drug-targeted genes were obtained through the STITCH database. A PPI network was constructed by combining drug-targeted genes with hub genes that affected the pathogenesis of KIRC to obtain final hub genes. Finally, combining hub genes and KIRC-associated hub genes, the pathways affected by drugs were explored by pathway enrichment analysis., Results: A total of 2,312 differentially expressed genes were found in patients, which were concentrated in immune cell activity, cytokine, and chemokine secretion pathways. Drug screening disclosed 5 drug candidates for KIRC treatment: fedratinib, Ly344864, geldanamycin, AS-605240, and luminespib. Based on drug-targeted genes and KIRC-associated hub genes, 16 hub genes were screened out. Pathway enrichment analysis revealed that drugs mainly affected pathways such as neuroactive ligand pathways, cell adhesion, and chemokines., Conclusion: The above results indicated that fedratinib, LY 344864, geldanamycin, AS-605240, and luminespib could be used as candidates for KIRC therapy. The findings from this study will make contributions to the treatment of KIRC in the future., (© 2021 The Author(s). Published by S. Karger AG, Basel.)

Glioblastoma (GBM) is a highly malignant and aggressive primary brain tumor mostly prevalent in adults and is associated with a very poor prognosis. Moreover, only a few effective treatment regimens are available due to their rapid invasion of the brain parenchyma and resistance to conventional therapy. However, the fast development of cancer immunotherapy and the remarkable survival benefit from immunotherapy in several extracranial tumor types have recently paved the way for numerous interventional studies involving GBM patients. The recent success of checkpoint blockade therapy, targeting immunoinhibitory proteins such as programmed cell death protein-1 and/or cytotoxic T lymphocyte-associated antigen-4, has initiated a paradigm shift in clinical and preclinical investigations, and the use of immunotherapy for solid tumors, which would be a potential breakthrough in the field of drug therapy for the GBM treatment. However clinical trial showed limited benefits for GBM patients. The main reason is drug resistance. This review summarizes the clinical research progress of immune checkpoint molecules and inhibitors, introduces the current research status of immune checkpoint inhibitors in the field of GBM, analyzes the molecular resistance mechanism of checkpoint blockade therapy, proposes corresponding re-sensitive strategies, and describes a reference for the design and development of subsequent clinical studies on immunotherapy for GBM., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Zhang, Wei, Ye, Kang and You.)

Chemotherapy resistance is one of the major challenges for the treatment of hepatocellular carcinoma (HCC). In order to investigate the mechanisms involved in chemoresistance of HCC, we established cisplatin (CDDP) and doxorubicin (Dox) resistant HCC cells. The expression of transcriptional coactivator with PDZ-binding motif (TAZ), one of the major downstream effectors of Hippo pathway, was upregulated in chemoresistant HCC cells. Targeted inhibition of TAZ via its siRNAs can restore CDDP and Dox sensitivity of chemoresistant HCC cells. The upregulation of TAZ increased the expression of IL-8 in HCC/CDDP and HCC/Dox cells. Recombinant IL-8 (rIL-8) antagonized the increased chemosensitivity mediated by TAZ knockdown. Mechanistically, TAZ can directly bind with the promoter of IL-8 to activate its transcription in chemoresistant HCC cells. Collectively, our data showed that TAZ-regulated expression of IL-8 was involved in chemoresistance of HCC cells. It indicated that targeted inhibition of TAZ/IL-8 axis might be helpful to improve chemotherapy efficiency for HCC., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Purpose: Combined chemotherapeutic drug and protein drug has been a widely employed strategy for tumor treatment. To realize both tumor accumulation and deep tumor penetration for drugs with different pharmacokinetics, we propose a structure-transformable, thermo-pH dual responsive co-delivery system to co-load granzyme B/docetaxel (GrB/DTX)., Methods: Thermo-sensitive hydrogels based on diblock copolymers (mPEG- b -PELG) were synthesized through ring opening polymerization. GrB/DTX mini micelles (GDM) was developed by co-loading these two drugs in pH-sensitive mini micelles, and the GDM-incorporated thermo-sensitive hydrogel (GDMH) was constructed. The thermo-induced gelation behavior of diblock copolymers and the physiochemical properties of GDMH were characterized. GDMH degradation and deep tumor penetration of released mini micelles were confirmed. The pH-sensitive disassembly and lysosomal escape abilities of released mini micelles were evaluated. In vitro cytotoxicity was studied using MTT assays and the in vivo antitumor efficacy study was evaluated in B16-bearing C57BL/6 mice., Results: GDMH was gelatinized at body temperature and can be degraded by proteinase to release mini micelles. The mini micelles incorporated in GDMH can achieve deep tumor penetration and escape from lysosomes to release GrB and DTX. MTT results showed that maximum synergistic antitumor efficacy of GrB and DTX was observed at mass ratio of 1:100. Our in vivo antitumor efficacy study showed that GDMH inhibited tumor growth in the subcutaneous tumor model and in the post-surgical recurrence model., Conclusion: The smart-designed transformable GDMH can facilitate tumor accumulation, deep tumor penetration, and rapid drug release to achieve synergistic chemo-protein therapy., Competing Interests: The authors declare that there are no conflicts of interest., (© 2020 Pang et al.)

Background: The prognosis for relapsed or refractory acute myeloid leukemia (RR-AML) in children is poor, and the preferred salvage chemotherapy is unclear. One regimen is cladribine, cytarabine, and granulocyte-colony stimulating factor (CLAG), but little is known about its efficacy and safety in children with RR-AML., Methods: We enrolled RR-AML patients aged 0-18 years who received modified CLAG regimen for re-induction between July 1, 2015 and April 1, 2018, or conventional induction between August 1, 2011 and April 1, 2018. Patients were followed up to March 31, 2019. Patients underwent allogeneic stem cell transplantation (allo-SCT) or chemotherapy after the induction of complete remission (CR). The CR rate, survival, and side effects were analyzed., Results: The CR rate for induction was 66.7% after one cycle and 75.0% after two cycles of the CLAG regimen in 12 children. The nine children who received conventional chemotherapy had a CR rate of 22.2% after one cycle and 33.3% after two cycles (P = 0.087 vs. CLAG). The 3-year event-free survival (EFS) of the CLAG group and the conventional treatment group were 44.4 ± 15.7% and 22.2 ± 13.8% (P = 0.112). The 3-year overall survival of the two groups were 59.5 ± 16.2% and 22.2% ± 13.8% (P = 0.057). The 3-year EFS for allo-SCT and chemotherapy after CLAG regimen was 66.7 ± 19.2% and 25.0 ± 21.7% (P = 0.015). A single case of chemotherapy-related death was recorded., Conclusion: Our data suggest a promising CR rate using CLAG salvage treatment in childhood RR-AML. Allo-SCT after CR may improve the long-term outcome in these patients.

Protein kinase (CK2) has emerged as an attractive cancer therapeutic target and recent efforts have been made to develop its inhibitors. However, the development of selective inhibitors remains challenging because of the highly conserved ATP-binding pocket (orthosteric site) of kinase family. As an alternative strategy, allosteric inhibitors, by targeting the much more diversified allosteric site relative to the conserved ATP-binding site, achieve better pharmacological advantages than orthosteric inhibitors. Traditional serendipitous screening and structure-based design are robust tools for the discovery of CK2 allosteric inhibitors. In this review, we summarize the recent advances in the identification of CK2 allosteric inhibitors. Firstly, we briefly present the CK2 allosteric sites. Then, the allosteric inhibitors targeting the well-elucidated allosteric sites (α/β interface, αD pocket and interface between the Glycine-rich loop and αC-helix) are highlighted in the discovery process and possible binding modes with the allosteric sites are described. This study is expected to provide valuable clues for the design of CK2 allosteric inhibitors.

KIT is a type-3 receptor tyrosine kinase that is frequently mutated at exon 11 or 17 in a variety of cancers. First-generation KIT tyrosine kinase inhibitors (TKI) are ineffective against KIT exon 17 mutations, which favor an active conformation that prevents these TKIs from binding. The ATP-competitive inhibitors, midostaurin and avapritinib, which target the active kinase conformation, were developed to inhibit exon 17-mutant KIT. Because secondary kinase domain mutations are a common mechanism of TKI resistance and guide ensuing TKI design, we sought to define problematic KIT kinase domain mutations for these emerging therapeutics. Midostaurin and avapritinib displayed different vulnerabilities to secondary kinase domain substitutions, with the T670I gatekeeper mutation being selectively problematic for avapritinib. Although gatekeeper mutations often directly disrupt inhibitor binding, we provide evidence that T670I confers avapritinib resistance indirectly by inducing distant conformational changes in the phosphate-binding loop. These findings suggest combining midostaurin and avapritinib may forestall acquired resistance mediated by secondary kinase domain mutations. SIGNIFICANCE: This study identifies potential problematic kinase domain mutations for next-generation KIT inhibitors midostaurin and avapritinib., (©2019 American Association for Cancer Research.)

Protein kinase CK2 has emerged as an attractive cancer therapeutic target. Previous studies have highlighted the challenge of optimizing CK2 ATP-competitive inhibitors that have low druggability due to their polycyclic ring scaffolds. Therefore the development of novel inhibitors with non-polycyclic scaffolds emerges as a promising strategy for drug discovery targeting CK2. In this current study, based on the similar predicted binding poses of the linear 2-propenone scaffold of isoliquiritigenin with that of the polycyclic inhibitor CX-4945, a series of 2-propenone derivatives containing an amine-substituted five-membered heterocycle and a benzoic acid were designed, synthesized and evaluated for their in vitro CK2 inhibition and anti-cancer activity. Compound 8b was found to be the most potent CK2 inhibitor (IC 50  = 0.6 μM) with the anti-proliferative activity on HepG2 cancer cells (IC 50  = 14 μM), compared to the activity of isoliquiritigenin (IC 50  = 17 μM and 51 μM, respectively). Molecular docking was performed to understand the binding modes of the newly designed 2-propenone derivatives with CK2. Compound 8b formed the most favorable network of hydrogen bonds with both the hinge region and positive area. Our results indicate that CK2 derivatives with a linear 2-propenone scaffold are promising candidates for anti-cancer drug discovery., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Purpose: To further enhance the antitumor efficacy through targeted delivery, DTX loaded lipid-based-nanosuspensions (DTX-LNS) were prepared and functionalized by PEGylation or NGR modification to develop DSPE-PEG 2000 modified DTX-LNS (P-DTX-LNS) or DSPE-PEG 2000 -NGR modified DTX-LNS (N-DTX-LNS), respectively. Methods: Based on our previous work, functionalized DTX-LNS including P-DTX-LNS and N-DTX-LNS were prepared using thin-film hydration, and then characterized. Release behavior, stability in vitro, cytotoxicity and cellular uptake of functionalized LNS were observed. To demonstrate tumor targeting efficiency of functionalized DTX-LNS, in vivo real-time and ex vivo imaging study were conducted. Furthermore, therapeutic efficacy in vivo was evaluated in an H22-bearing mice model. Results: Functionalized DTX-LNS 100-110 nm in diameter were successfully prepared and exhibited good stability under various conditions. In vitro release studies demonstrated that DTX was released from functionalized DTX-LNS steadily and reached approximately 95% at 48 hrs. Functionalized DTX-LNS showed dose-dependent cytotoxicity and time-dependent internalization in human hepatocellular liver carcinoma cells (HepG2) cells. In vivo real-time and ex vivo imaging results indicated that tumor targeting efficiencies of P-DiR-LNS and N-DiR-LNS were 29.9% and 34.3%, respectively. Moreover, evaluations of in vivo antitumor efficacy indicated that functionalized DTX-LNS effectively inhibited tumor growth with low toxicity. Conclusion: The functionalized LNS exhibited suitable particle size, nearly spherical structure, enough drug loading and great potentials for large-scale production. The results in vitro and in vivo demonstrated that functionalized LNS could realize tumor targeting and antitumor efficacy. Consequently, functionalized DTX-LNS could be expected to be used for tumor targeting therapy., Competing Interests: The authors report no conflicts of interest in this work.

Protein kinase CK2 is considered as an emerging target in cancer therapy, and recent efforts have been made to develop its ATP-competitive inhibitors, but achieving selectivity with respect to related kinases remains challenging because of the highly conserved ATP-binding pocket of kinases. Non-ATP competitive inhibitors might solve this challenge; one such strategy is to identify compounds that target the CK2α/CK2β interface as CK2 holoenzyme antagonists. Here we improved the binding affinity to CK2α and cell-based anti-cancer activity of a CK2β-derived cyclic peptide (Pc) by combining structure-based computational design with experimental evaluation. By analyzing molecular dynamics simulations of Pc bound to CK2α, a series of Pc-derived peptides was rationally designed and synthesized to evaluate their binding affinity to CK2α, as well as anti-proliferative and pro-apoptotic effects against HepG2 cancer cell line. One amino acid substitutions on Pc, I192F, exhibited over 10-fold improvement in the predicted binding affinity to CK2α when compared to Pc, and a cell-permeable version, I192F-Tat, also demonstrated more potent anti-proliferative and pro-apoptotic effects against HepG2 compared to Pc. A second modification of Pc, H193W, also led to more potent cell-based activity, despite having weaker binding affinity (∼5×) to CK2α. The discovery of the I192F and H193W peptides provides new insights for further optimization of CK2 antagonist candidates as anti-cancer leads., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Aim: A hypoxia-activated combi-nitrosourea prodrug, N -(2-chloroethyl)- N '-2-(2-(4-nitrobenzylcarbamate)- O 6 -benzyl-9-guanine)ethyl- N -nitrosourea (NBGNU), was synthesized and evaluated for its hypoxic selectivity and anticancer activity in vitro . Results: The prodrug was designed as a tripartite molecule consisting of a chloroethylnitrosourea pharmacophore to induce DNA interstrand crosslinks (ICLs) and an O 6 -benzylguanine analog moiety masked by a 4-nitrobenzylcarbamate group to induce hypoxia-activated inhibition of O 6 -alkylguanine-DNA alkyltransferase. NBGNU was tested for hypoxic selectivity, cytotoxicity and DNA ICLs ability. The reduction product amounts, cell death rates and DNA ICL levels induced by NBGNU under hypoxic conditions were all significantly higher than those induced by NBGNU under normoxic conditions. Conclusion: The tripartite combi-nitrosourea prodrug exhibits desirable tumor-hypoxia targeting ability and abolished chemoresistance compared with the conventional chloroethylnitrosoureas.

Combination therapy is one of the important methods to improve therapeutic effect on the treatment of hepatocellular carcinoma (HCC). Sorafenib (SF) is a canonical US Food and Drug Administration-approved multikinase molecule inhibitor against HCC. However, therapeutic benefit with Sorafenib alone was usually unsatisfactory. Ceramide (CE) is an endogenous bioactive sphingolipid, which has a strong potential to suppress various tumors. The combination of SF and CE was hoping to exert maximum synergistic antitumor effect through different tumor-suppressible mechanisms. In this respect, SF and CE co-loaded liposomes (SF/CE-liposomes) were developed to verify synergistic antitumor efficacy. The optimal molar ratio of SF and CE was determined through combination index. SF/CE-liposomes were prepared by thin-film hydration method, which exhibited spherical or ellipsoidal shape. Particle size of SF/CE-liposomes was 174 ± 4 nm with homogeneous distribution. Release profile of SF demonstrated that addition of CE imposed no significant impact on the release of SF. SF/CE-liposomes exhibited acceptable stability in different media and desirable storage stability over 30 days at 4°C. In vitro cellular uptake confirmed that SF/CE-liposomes could be efficiently internalized into HepG2 cells. In vitro cytotoxicity evaluation indicated that SF/CE-liposomes exhibited higher cytotoxicity on HepG2 cells. IC 50 value of SF/CE-liposomes was 11.5 ± 0.44 μM, which was significantly lower than that of SF-liposomes ( ** p < 0.01). Evaluation of in vivo synergistic effect on H22-bearing mice verified that SF/CE-liposomes achieved robust antitumor activity in preventing tumor growth. All results suggested that SF/CE-liposomes might be served as an efficient co-delivery system for improving therapeutic efficacy of HCC.

Background: We previously developed a simple effective system based on oligodeoxynucleotides with CGA repeating units (CGA-ODNs) for Dox and siRNA intracellular co-delivery., Methods: In the present study, the in vitro cytotoxicity, gene transfection and in vivo safety of the co-delivery system were further characterized and discussed., Results: Compared with poly(ethyleneimine) (PEI), both CGA-ODNs and the pH-sensitive targeted coating, o -carboxymethyl-chitosan (CMCS)-poly(ethylene glycol) (PEG)-aspargine-glycine-arginine (NGR) (CMCS-PEG-NGR, CPN) showed no obvious cytotoxicity in 72 h. The excellent transfection capability of CPN coated Dox and siRNA co-loaded nanoparticles (CPN-PDR) was confirmed by real-time PCR and Western blot analysis. It was calculated that there was no significant difference in silencing efficiency among Lipo/siRNA, CPN-modified siRNA-loaded nanoparticles (CPN-PR) and CPN-PDR. Furthermore, CPN-PDR was observed to be significantly much more toxic than Dox- and CPN-modified Dox-loaded nanoparticles (CPN-PD), implying their higher antitumor potential. Both hemolysis tests and histological assessment implied that CPN-PDR was safe for intravenous injection with nontoxicity and good biocompatibility in vitro and in vivo., Conclusion: The results indicated that CPN-PDR could be a potentially promising co-delivery carrier for enhanced antitumor therapy., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Research of various diseases of the nervous system has shown that VEGF has direct neuroprotective effects in the central and peripheral nervous systems, and indirect effects on improving neuronal vessel perfusion which leads to nerve protection. In the tumors of the nervous system, VEGF plays a critical role in tumor angiogenesis and tumor progression. The effect of anti-VEGF treatment on nerve protection and function has been recently reported - by normalizing the tumor vasculature, anti-VEGF treatment is able to relieve nerve edema and deliver oxygen more efficiently into the nerve, thus reducing nerve damage and improving nerve function. This review aims to summarize the divergent roles of VEGF in diseases of the nervous system and the recent findings of anti-VEGF therapy in nerve damage/regeneration and function in tumors, specifically, in Neurofibromatosis type 2 associated schwannomas., (Copyright © 2017. Published by Elsevier Inc.)

Inspired by the significant anti-cancer activity of our previously screened natural ergosterol peroxide (EP, 1), we synthesized and characterized a series of novel 5α,8α-epidioxyandrost-3β-ol-17-(O-phenylacetamide)oxime derivatives (9a-o). The anti-proliferative activity of the synthesized compounds against human hepatocellular carcinoma cells (HepG2, Sk-Hep1) and human breast cancer cells (MCF-7, MDA-MB231) were investigated. Compounds 9d, 9f, 9h, 9j and 9m displayed good anti-proliferative activity (most IC 50 <20μM) in vitro. Furthermore, fluorescence imaging showed that the designed coumarin-9d conjugate (12) localized mainly in mitochondria, leading to enhanced anticancer activities over the parent structure., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

By inspiration of significant anti-cancer activity of our previously screened natural ergosterol peroxide (EP), a series of novel steroidal 5α,8α-endoperoxide derivatives 5a-d and 14a-f were designed, synthesized, and biologically evaluated for their in vitro anti-proliferative inhibitory and cytotoxic activity. The results revealed that most of these compounds showed moderate-to-excellent anti-proliferative effects against the tested cancer cell lines (i.e. HepG2, SK-Hep1, MDA-MB-231 and MCF-7). Among them, compound 5b and 14d exhibited preferable inhibitory activities (IC 50 of 5b and 14d are 8.07 and 9.50μM against HepG2, respectively). The structure-activity relationships indicated that incorporation the peroxidic bridge to the steroid scaffolds at C-5 and C-8 positions together with the aliphatic side-chain at the C-17 position would provide synergistic effect for the bioactivity., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Protein kinase CK2 has been considered as an attractive therapeutic target of cancer therapy. The tricyclic quinoline compound CX-4945 is the first representative of CK2 inhibitors used in human clinical trials. The binding of non-2,6-naphtyridine substituted compounds 27e (IC 50 > 500 nM) and 27h (IC 50 > 1000 nM) to CK2 is abolished. However, the unbinding mechanisms due to the key pharmacophore group replacement of compounds 27e and 27h are unveiled. In the present work, combined computational analysis was performed to investigate the underlying structural basis of the low-affinity of two systems. As indicated in the results, the loss of hydrogen bonds between the non-2,6-naphtyridine and the hinge region destroyed the proper recognition of the two complexes. Besides, the allosteric mechanisms between the deviated ligands and the changed regions (G-loop, C-loop and β4/β5 loop) are proposed. Furthermore, energetic analysis was evaluated by detailed energy calculation and residue-based energy decomposition. More importantly, the summary of known polar pharmacophore groups elucidates the pivotal roles of hinge region sub-pocket in the binding of CK2 inhibitors. These results provide rational clues to the fragment-based design of more potent CK2 inhibitors., Competing Interests: The authors declare no conflict of interest.

In an effort to discover potent camptothecin-derived antitumor agents, novel camptothecin analogues with sulfonylpiperazinyl motifs at position-7 were designed and synthesized. They were evaluated for in vitro cytotoxicity with the sulforhodamine-B (SRB) method in five types of human tumor cell lines, A-549, MDA-MB-231, KB, KB-VIN and MCF-7. With IC 50 values in the low μM to nM level, most of the new analogues showed greater cytotoxicity activity than the reference compounds irinotecan and topotecan. Furthermore, compounds 12l (IC 50 , 1.2nM) and 12k (IC 50 , 20.2nM) displayed the highest cytotoxicity against the multidrug-resistant (MDR) KB-VIN cell line and merit further development as preclinical drug candidates for treating cancer, including MDR phenotype. Our study suggested that integration of sulfonylpiperazinyl motifs into position-7 of camptothecin is an effective strategy for discovering new potent cytotoxic camptothecin derivatives., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Targeting the autophagic pathway is currently regarded as an attractive strategy for cancer drug discovery. Our previous work showed that IMB-6G is a novel N-substituted sophoridinic acid derivative with potent cytotoxicity against tumor cells, yet the effect of IMB-6G on autophagy and pancreatic cancer cell death remains unknown. Here, we show that IMB-6G inhibits the growth of MiaPaCa-2 and HupT-3 pancreatic cancer cells and induces caspase-mediated apoptosis, which is correlated with an accumulation of autophagic vacuoles. IMB-6G promotes autophagosome accumulation from the early stage of treatment but blocks autophagic flux in the degradation stage, mainly through attenuation of lysosomal cathepsin activity in pancreatic cancer cells. Moreover, IMB-6G triggers lysosomal membrane permeabilization (LMP), followed by cathepsin B/CTSB and cathepsin D/CTSD release from lysosomes into the cytoplasm. Inhibition of autophagosome formation with siRNA against autophagy protein 5 (Atg5) attenuates IMB-6G-induced LMP and apoptosis. Furthermore, cathepsin inhibitors relieve IMB-6G-induced apoptosis as well. Altogether, our findings demonstrate that IMB-6G is a novel autophagy inhibitor, which induces autophagy-dependent apoptosis through autophagosomal-cathepsin axis in pancreatic cancer cells and indicate the potential value of IMB-6G as a novel antitumor drug candidate., Competing Interests: The authors declare no competing financial interests.

Mucosa-associated lymphoid tissue (MALT) lymphoma usually originates from the stomach and presents with low 18 F-fluorodeoxyglucose (FDG) avidity with average maximum standard uptake value of 3.6. Colorectal MALT lymphoma is a rare entity that contributes to 1.6% of all MALT lymphomas and < 0.2% of large intestinal malignancies. The case reported herein firstly revealed stage IIE MALT lymphoma with unexpected higher 18 F-FDG avidity of 18.9 arising at the colorectal anastomosis in a patient with a surgical history for sigmoid adenocarcinoma, which was strongly suspected as local recurrence before histopathological and immunohistochemical examinations. After accurate diagnosis, the patient received four cycles of standard R-CVP regimen (rituximab, cyclophosphamide, vincristine and prednisone), combined target therapy and chemotherapy, instead of radiotherapy recommended by National Comprehensive Cancer Network guidelines. He tolerated the treatment well and reached complete remission., Competing Interests: Conflict-of-interest statement: The authors declare that there is no conflict of interest related to this report.

Drug combinations are widely employed in chemotherapy for colorectal cancer treatment. However, traditional cocktail combination in clinic causes the uncertainty of the treatment, owing to varying pharmacokinetics of different drugs. The aim of this study was to design co-loaded liposomes to achieve the synchronised delivery and release. Oxaliplatin and irinotecan hydrochloride, as one of recommended combination schemes for the treatment of colorectal cancer in clinic, were co-loaded into the liposomes. The particle sizes of the liposomes were <200nm with uniform size distribution. In vitro release study showed that both drugs could be synchronously released from the liposomes, which means the optimized synergistic ratio of two drugs could be achieved. In vitro cellular uptake revealed that co-loaded liposomes could efficiently deliver different drugs into the same cells, indicating their potential as carriers for enhancing the cancer therapy. CLSM images of cryo-sections for in vivo co-delivery study also revealed that co-loaded liposomes had superior ability to co-deliver both the cargoes into the same tumor cells. Besides, in vivo NIRF imaging indicated that the liposomes could increase the drug accumulation in tumor compared with free drug. In vitro cytotoxicity evaluation demonstrated that co-loaded liposomes exhibited higher cytotoxicity than the mixture of single loaded liposomes in both CT-26 and HCT-116 cells. Furthermore, co-loaded liposomes also presented superior anti-tumor activity in CT-26 bearing BALB/c mice. In vivo safety assessment demonstrated that liposomes had lower toxicities than their solution formulations. These results indicated that oxaliplatin and irinotecan hydrochloride co-loaded liposomes would be an efficient formulation for improving colorectal cancer therapy with potential clinical applications., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Prolonged treatment of breast cancer with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) often results in acquired resistance and a narrow therapeutic index. One strategy to improve the therapeutic effects of EGFR TKIs is to combine them with drugs used for other clinical indications. Ethacrynic acid (EA) is an FDA approved drug that may have antitumor effects and may enhance the cytotoxicity of chemotherapeutic agents by binding to glutathione and inhibiting WNT signaling. While the α,β-unsaturated-keto structure of EA is similar to that of irreversible TKIs, the mechanism of action of EA when combined with irreversible EGFR TKIs in breast cancer remains unknown. We therefore investigated the combination of irreversible EGFR TKIs and EA. We found that irreversible EGFR TKIs and EA synergistically inhibit breast cancer both in vitro and in vivo. The combination of EGFR TKIs and EA induces necrosis and cell cycle arrest and represses WNT/β-catenin signaling as well as MAPK-ERK1/2 signaling. We conclude that EA synergistically enhances the antitumor effects of irreversible EGFR TKIs in breast cancer., Competing Interests: The authors declare no competing financial interests.

Citronellol-cabazitaxel (CIT-ss-CTX) conjugate self-assembled nanoparticles (CSNPs) were designed and prepared by conjugating cabazitaxel with citronellol via the disulfide bond that is redox-sensitive to the high concentration of glutathione within tumor cells. Notably, the CSNPs maintained in the cell cytotoxicity. Moreover, the AUC0-t of CSNPs was 6.5-fold higher than that of cabazitaxel solutions and the t1/2 was prolonged 2.3 times. Furthermore, we found that CSNPs could be employed as an efficient carrier for other hydrophobic drugs or imaging agents. Thus, the in vivo targeting study was implemented via using 1,1-dioctadecyl-3,3,3,3-tetramethylindotricarbocyanine iodide (DiR)-loaded CSNPs as imaging agent, which showed CSNPs could effectively accumulate at the tumor site. Curcumin, a hydrophobic anticancer drug, was successfully loaded in CSNPs which exhibits good stability and synergistic antitumor effects. The citronellol-cabazitaxel conjugate therefore has a promising perspective as a multifunctional nanomedicine for combination therapy and theranostics attributed to its long-circulation property, redox-sensitive mechanism, and high drug coloading capability.

Polymer-drug conjugated micelles have many advantages as delivery vehicles of anticancer drugs. They can increase the solubility of hydrophobic drugs, extend the circulation time in vivo, improve the stability of anticancer drugs, reduce systemic toxicity and enhance the therapeutic effect of anticancer drugs, etc. moreover, a variety of polymers containing functional groups can also be used to prepare multi-functional polymer-drug conjugated micelles. In this article,polymer-drug conjugated micelles are reviewed and various multi-functional modification of polymer-drug conjugated micelles are introduced, and the recent progress of polymer-drug conjugated micelles in the delivery of anticancer drugs is summarized.

The drug resistance of CENUs induced by O(6)-alkylguanine-DNA alkyltransferase (AGT), which repairs the O(6)-alkylated guanine and subsequently inhibits the formation of dG-dC cross-links, hinders the application of CENU chemotherapies. Therefore, the discovery of CENU analogs with AGT inhibiting activity is a promising approach leading to novel CENU chemotherapies with high therapeutic index. In this study, a new combi-nitrosourea prodrug 3-(3-(((2-amino-9H-purin-6-yl)oxy)methyl)benzyl)-1-(2-chloroethyl)-1-nitrosourea (6), designed to release a DNA cross-linking agent and an inhibitor of AGT, was synthesized and evaluated for its antitumor activity and ability to induce DNA interstrand cross-links (ICLs). The results indicated that 6 exhibited higher cytotoxicity against mer(+) glioma cells compared with ACNU, BCNU, and their respective combinations with O(6)-benzylguanine (O(6)-BG). Quantifications of dG-dC cross-links induced by 6 were performed using HPLC-ESI-MS/MS. Higher levels of dG-dC cross-link were observed in 6-treated human glioma SF763 cells (mer(+)), whereas lower levels of dG-dC cross-link were observed in 6-treated calf thymus DNA, when compared with the groups treated with BCNU and ACNU. The results suggested that the superiority of 6 might result from the AGT inhibitory moiety, which specifically functions in cells with AGT activity. Molecular docking studies indicated that five hydrogen bonds were formed between the O(6)-BG analogs released from 6 and the five residues in the active pocket of AGT, which provided a reasonable explanation for the higher AGT-inhibitory activity of 6 than O(6)-BG., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

A series of novel nitrogen mustard sophoridinic acid derivatives were designed, synthesized and evaluated for their cytotoxicity. Of the newly synthesized compounds, compound 6 exhibited a potent effect against hepatocellular carcinoma in vitro and in vivo. SAR analysis indicated that introduction of a nitrogen mustard group to the structure of sophoridinic acid significantly enhance the antitumor activity. Moreover, molecular docking study exhibited benzyl group introduced to the nitrogen atom at the 12-position and aryl nitrogen mustard group at the 4'-carboxyl region for compound 6 were beneficial for the higher anticancer activity. This work provides useful information for further structural modifications of these compounds and for the synthesis of new, potent antitumor agents., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Combination therapy has become an important strategy for treating cancer in recent years. Ceramide, which is a powerful tumor suppressor, regulating the processes of cell proliferation, differentiation, senescence and apoptosis, has attracted tremendous attention in combination therapy for cancer treatment. It has been demonstrated that combination of chemotherapeutic drugs and ceramide led to a reversion of multidrug resistance (MDR), synergistic tumor inhibition while simultaneously reducing systemic toxicity in cancer treatment. In this review, we aim to reveal the interactions between some anticancer drugs and ceramide, and summarize the research progress in combination therapies based on ceramide. Synthesis, metabolism and anticancer mechanisms of ceramide were described. Furthermore, the advantages of combination of chemotherapeutic drugs and exogenous ceramide, cerami-degenerating agents or modulators of ceramide metabolism were highlighted. Future perspective and problems to solve before the extension of ceramide's applications were also discussed. It is hoped that this review will provide new ideas for combination therapies in cancer treatment.

Background: Chronic myeloid leukemia (CML) with the e19a2 transcript coding for p230 is a rare disease. ABL1 kinase domain mutations in CML with the e19a2 rearrangement were seldom reported., Methods: The clinical characteristics of a 45-year-old Chinese female CML patient with e19a2 BCR/ABL1 transcript were described. The mutation on the ABL gene exons was determined by sequencing the cDNA of the μ-BCR-ABL fusion product., Results: This patient developed an acquired resistance associated with two p-BCR/ABL1 mutations (E255K and G250E) during treatment with imatinib., Conclusions: Here, we report a CML patient with e19a2 transcripts, carrying E255K and G250E mutation and experience of nilotinib treatment. The μ-BCR/ABL1 mutation should be investigated after imatinib treatment failure.

Phellinus is a kind of rare medicinal fungus that has a variety of physiological activities include anti-cancer, anti-liver fibrosisa, antioxidant and so on. Phellinus contains polysaccharides, steroids, terpenoids, flavonoids, pyrone, furan, alkaloids and other substances. Polysaccharide extracts of phellinus showed obvious antitumor effect and has been a hot research field in recent years. It was also found other extracts of phellinus such as ethyl acetate extract exhibited anticancer activity. Thus, the antitumor effect of different extract, especially the anti-cancer mechanism were discussed in this review.

Thyroid cancer-1 (TC-1), a natively disordered protein, is widely expressed in vertebrates and overexpressed in many kinds of tumors. However, its exact role and regulation mechanism in human non-small cell lung cancer (NSCLC) are still unclear. In the present study, we found that TC-1 is highly expressed in NSCLC and that its aberrant expression is strongly associated with NSCLC cell proliferation. Exogenous TC-1 overexpression promotes cell proliferation, accelerates the cell G1-to-S-phase transition, and reduces apoptosis in NSCLC. The knockdown of TC-1, however, inhibits NSCLC cell proliferation, cycle transition, and apoptosis resistance. Furthermore, we also demonstrated that PD173074, which functions as an inhibitor of the TC-1 in NSCLC, decreases the expression of TC-1 and inhibits TC-1 overexpression mediated cell proliferation in vitro and in vivo. Nevertheless, the inhibition function of PD173074 on NSCLC cell proliferation was eliminated in cells with TC-1 knockdown. These results suggest that PD173074 plays a significant role in TC-1 overexpression mediated NSCLC cell proliferation and may be a potential intervention target for the prevention of cell proliferation in NSCLC.

Purpose: To synthesize and evaluate the antitumor efficacy of double-targeted docetaxel (DTX)-carboxymethyl chitosan (CMCS)-PEG-NGR (DTX-CPN) conjugates that could target to CD13 over-expressed tumor neovascular endothelium cells and tumor cells., Methods: DTX was conjugated to CMCS via biodegradable linker and cNGR was applied to endow the conjugates with double targeting ability. The physiochemical properties and stability of this DTX-CPN conjugates were characterized. Cellular uptake study was carried out to evaluate the targeting ability of DTX-CPN conjugates. Cytotoxicity and apoptosis analysis were conducted to evaluate in vitro antitumor effects. In vivo antitumor efficacy was investigated in B16 murine melanoma model., Results: DTX-CPN conjugates could self-assemble into nanoparticles in water and were stable in plasma. cNGR modification could promote the cellular uptake of DTX-CPN conjugates in CD13 positive HUVEC and B16 cells, leading to more significant cytotoxicity and apoptosis effect than non-targeted conjugates. DTX-CPN conjugates also exhibited better antitumor effect than non-targeted conjugates and Duopafei® in a B16 murine melanoma model., Conclusions: Double-targeted DTX-CPN conjugates could efficiently target to tumor neovascular cells and tumor cells, and achieve good antitumor effects. DTX-CPN conjugates may be promising candidate for one-double targeting cancer therapy.

The purpose of this research is to develop and evaluate Pluronic P123 (P123)-docetaxel (DTX) conjugate that could form core-shell-type micelles in aqueous solution. DTX was covalently conjugated to P123 via ester bond after the activation of DTX by succinic anhydride. The structure of P123-DTX conjugate was confirmed by 1H-NMR. The self-assembly behavior of the P123-DTX conjugate in aqueous solution was characterized by the measurement of critical micelle concentration (CMC). The CMC of P123-DTX conjugate was (1.34 +/- 0.05) x 10(-5) mol/L, which was lower than that of P123 ((1.91 +/- 0.07) x 10(-5) mol/L). The DTX content in the conjugate could reach 13.69% (wt.%). TEM and DLS analysis showed that the conjugate formed approximately spherical micelles with mean particle size of 85.3 +/- 1.59 nm. In vitro release of DTX from the conjugate micelles showed pH dependence, being faster at lower pH value than that at pH 7.4. In vitro cytotoxicity of P123-DTX conjugate micelles was evaluated by MTT method against HepG2, MCF-7 and B16 cell lines and the result indicated that P123-DTX conjugate micelles showed lower cytotoxicity than the DTX injection-Duopafei. Compared with Duopafei, in vivo antitumor activity of P123-DTX conjugate micelles in Kunming mice bearing B16 tumor was more effective and less toxic. These results indicated that the P123-DTX conjugate micelles prepared in this study may be considered as an alternative and promising DTX delivery system.

The purpose of this study is to synthesis and evaluate the antitumor efficacy of a novel carboxymethyl chitosan-docetaxel (CMCS-DTX) conjugates and the availability of CMCS as the polymer material in polymer-drug conjugates development. Docetaxel (DTX) was attached to carboxymethyl chitosan (CMCS) via biodegradable linker for the first time and the weight percentage of DTX in the CMCS-DTX conjugates was up to 20%. The resulting CMCS-DTX conjugates could spontaneously self-assemble into nanoparticles in aqueous buffer, with uniform size of 127.2±3.58 nm and zeta potential of -25.65 mV. The stability test result showed that only 12.46% of DTX was released after incubation in plasma for 48 h, indicating good stability of CMCS-DTX conjugates in plasma. The results of in vitro cytotoxicity and Hoechst staining indicated that CMCS-DTX conjugates exhibited significant cytotoxicity against B16 and HepG2 cells. CMCS-DTX conjugates also displayed better antitumor effect than Duopafei® by inhibiting tumor growth and prolonging the survival time of B16 melanoma bearing mice more effectively (the median survival time was >30 days for CMCS-DTX conjugates versus 24 days for the Duopafei®). Besides, CMCS-DTX conjugates demonstrated an excellent safety profile with a maximum tolerated dose (MTD) of >250 mg/kg in mice, which was more than 4 fold higher than that of Duopafei® (50 mg/kg). CMCS-DTX conjugates could be exploited as a promising platform for the effective delivery of DTX and CMCS was a favorable choice as the polymer material in polymer-drug conjugates development., (Copyright © 2013 Elsevier B.V. All rights reserved.)

N3-o-toluyl-fluorouracil (TFu) was a potent water-insoluble prodrug of 5-fuorouracil (5-Fu). To improve the solubility of TFu, TFu loaded nanosuspension (TFu-LNS) was prepared by high-pressure homogenization method. The results of in vitro release studies showed that 5-Fu was sustained released from TFu-LNS. Then in vitro antitumor activity of TFu-LNS in terms of antiproliferative activity, induction of apoptosis and G1 cycle arrest on human breast adenocarcinoma cell line (MCF-7) and human gastric carcinoma cell line (BGC) was evaluated. The results of MTT assay showed that TFu-LNS exhibited higher antiproliferative activity against MCF-7 and BGC cells than TFu DMSO-water solution and 5-Fu solution. The apoptosis induced by TFu-LNS was assessed by Annexin V-FITC/PI double staining and Tunnel assay. And the results of two methods both clearly indicated that the superiority of TFu-LNS to TFu DMSO-water solution and 5-Fu solution in increasing the apoptosis rate of MCF-7 and BGC cells. The results of flow cytometric (FCM) analysis demonstrated that TFu-LNS could induce G1 cycle arrest of MCF-7 and BGC cells. Furthermore, in vivo pharmacokinetics study in Wistar rats indicated that TFu-LNS was capable of increasing the parameters of AUC(0-infinity) and MRT significantly by sustained releasing 5-Fu. Therefore, the overall results suggested that the TFu-LNS could enhance anti-tumor effect and hold great potential to be developed for cancer treatments.

Docetaxel has been recognized as one of the most efficient anticancer drugs over the past decade; however, its poor water solubility and systemic toxicity have greatly limited its clinical application. In recent decades, the emergence of nanotechnology has provided new drug delivery systems for docetaxel, which can improve its water solubility, minimize the side effects and increase the tumor-targeting distribution by passive or active targeting. This review focuses on the research progress in nanoformulations related to docetaxel delivery - such as polymer-based, lipid-based, and lipid-polymer hybrid nanocarriers, as well as inorganic nanoparticles - addressing their structures, characteristics, preparation, physicochemical properties, methods by which drugs are loaded into them, and their in vitro and in vivo efficacies. Further, the targeted ligands used in the docetaxel nanoformulations, such as monoclonal antibodies, peptides, folic acid, transferrin, aptamers and hyaluronic acid, are described. The issues to overcome before docetaxel nanoformulations can be used in clinical and commercial applications are also discussed.

The purpose of this study was to develop two novel drug delivery systems based on biodegradable docetaxel-lipid-based-nanosuspensions. The first one was poly(ethylene glycol)- modified docetaxel-lipid-based-nanosuspensions (pLNS). It was developed to increase the cycle time of the drug within the body and enhance the accumulation of the drug at the tumor site. The second one was targeted docetaxel-lipid-based-nanosuspensions (tLNS) using folate as the target ligand. The tLNS could target the tumor cells that overexpressed folate receptor (FR). The morphology, particle size, and zeta potential of pLNS and tLNS were characterized, respectively. The in vitro cytotoxicity evaluation of Duopafei(®), pLNS, and tLNS were performed in human hepatocellular liver carcinoma HepG2 (FR-) and B16 (FR+) cells, respectively. The in vivo antitumor efficacy and pharmacokinetics, as well as the drug tissue distribution, were evaluated in Kunming mice bearing B16 cells. The particle size of pLNS was 204.2 ± 6.18 nm and tLNS had a mean particle size of 220.6 ± 9.54 nm. Cytotoxicity of tLNS against B16 (FR+) cell lines was superior to pLNS (P < 0.05), while there was no significant difference in the half maximum inhibitory concentration values for HepG2 (FR-) cells between pLNS and tLNS. The results of the in vivo antitumor efficacy evaluation showed that tLNS exhibited higher antitumor efficacy by reducing tumor volume (P < 0.01) compared with Duopafei and pLNS, respectively. The results of the in vivo biodistribution study indicate that the better antitumor efficacy of tLNS was attributed to the increased accumulation of the drug in the tumor.

The purpose of the study was to design lipid-based-nanosuspensions (LNS) for Docetaxel (DTX) without Tween 80 for clinical intravenous administration (i.v.). DTX-LNS were prepared by high pressure homogenization method, and then lyophilization was carried out to improve the stability. The physical-chemical properties in terms of particle size, size distribution, zeta potential and morphology were evaluated, respectively. The in vitro cytotoxic activity was assessed by MTT against SKOV-3 and malignant melanoma B16 cells. The in vivo pharmacokinetics, tissue distribution as well as antitumor efficacy were investigated in B16 melanoma-bearing Kunming mice. The particle size and zeta potential of DTX-LNS were (200.0 ± 3.42)nm and (-11.15 ± 0.99)mV, respectively. Compared with Duopafei, it was shown that DTX-LNS exhibited higher antitumor efficacy by reducing tumor volume (P<0.05) and increasing survival rate in B16 melanoma-bearing mice and strongly reduced the anticancer drug toxicity. The results of biodistribution studies clearly indicated the superiority of DTX-LNS to Duopafei in increasing the accumulation of DTX within tumor and the organs rich in macrophages (liver, lungs and spleen), while, the drug concentration in heart and kidney decreased. Together these results suggested that DTX-LNS could effectively inhibit tumor growth, reduce toxicity during the therapeutic procedure and hold the potential to be an appropriate choice for the clinical administration of DTX., (Copyright © 2011 Elsevier B.V. All rights reserved.)

In this work, novel docetaxel (DTX) -loaded Tween 80-free Pluronic P123 (P123) micelles with improved therapeutic effect were developed. The freeze-dried DTX-loaded P123 micelles (DTX-micelles) were analyzed by HPLC, TEM and DLS to determine the DTX loading, micelle morphology, size, respectively. The in vitro cytotoxic activity of DTX-micelles in HepG2, A549 and malignant melanoma B16 cells were evaluated by MTT assay. The corresponding in vivo antitumor efficacy was assessed in Kunming mice bearing B16 tumor after intravenous administration. The DTX-loading and efficiency into the micelles were 2.12 ± 0.09% and 86.34 ± 3.32%, respectively. The DTX-micelles were spherical with a mean particle size of 50.7 nm and size distribution from 22 to 84 nm, which suggested that they should be able to selectively accumulate in solid tumors by means of EPR effect, with a zeta potential of -12.45 ± 3.24 mV. The in vitro release behavior of DTX from DTX-micelles followed the Weibull equation. Compared with Duopafei(®), DTX-micelles showed higher cytotoxicity against HepG2 (P < 0.01), A549 (P < 0.05) and B16 (P < 0.01) cells. In addition, DTX-micelles exhibited remarkable antitumor activity and reduced toxicity on B16 tumor in vivo. The tumor inhibition rates (TIR) of DTX-micelles was 91.6% versus 76.3% of Duopafei(®) (P < 0.01). These results suggested that P123 micelles might be considered as an effective DTX delivery system.

This study reports two novel 5-fluorouracil-substituted ampelopsin derivatives. The structures of two new derivatives were characterized by elemental analysis, 1H-NMR, 13C-NMR, IR and MS. Their anticancer activities in vitro against two cancer cell lines, K562 and K562/ADR, were investigated using the MTT assay, and the results showed that the two new compounds were more effective than reference drugs such as ampelopsin and verapamil.

Nanotechnology has a profound effect on many areas of scientific research. Having grown exponentially, the focus of nanotechnology has been on therapeutic activity, such as cancer treatment. Lipid-based nanocarriers have attracted increasing scientific and commercial attention in the last few years as alternative carriers for the delivery of anticancer drugs. Lipid-based nanocarriers have played significant roles in the formulation of anticancer drugs to improve therapeutics. Shortcomings frequently encountered with anticancer compounds, such as poor solubility, normal tissue toxicity, poor specificity and stability, as well as the high incidence rate of drug resistance, are expected to be overcome through use of lipid-based nanocarriers. In this review, the advantages and methods of using nanocarriers to improve cancer treatment efficiency will be discussed. In addition, types of lipid-based nanocarriers are presented and hotspots in research are highlighted. It is anticipated that, in the near future, lipid-based nanocarriers will be further improved to deliver cytotoxic anticancer compounds in a more efficient, specific and safe manner.