Anti-proliferative and angio-suppressive effect of Stoechospermum marginatum (C. Agardh) Kutzing extract using various experimental models

BACKGROUND/OBJECTIVES

Abundant consumption of seaweeds in the diet is epidemiologically linked to the reduction in risk of developing cancer. In larger cases, however, identification of particular seaweeds that are accountable for these effects is still lacking, hindering the recognition of competent dietary-based chemo preventive approaches. The aim of this research was to establish the antiproliferative potency and angiosuppressive mode of action of Stoechospermum marginatum seaweed methanolic extract using various experimental models.

MATERIALS/METHODS

Among the 15 seaweeds screened for antiproliferative activity against Ehrlich ascites tumor (EAT) cell line, Stoechospermum marginatum extract (SME) was found to be the most promising. Therefore, it was further investigated for its anti-proliferative activity in-vitro against choriocarcinoma (BeWo) and non-transformed Human embryonic kidney (HEK 293) cells, and for its anti-migratory/tube formation activity against HUVEC cells in-vitro. Subsequently, the angiosuppressive activity of S. marginatum was established by inhibition of angiogenesis in in-vivo (peritoneal angiogenesis and chorioallantoic membrane assay) and ex-vivo (rat cornea assay) models.

RESULTS

Most brown seaweed extracts inhibited the proliferation of EAT cells, while green and red seaweed extracts were much less effective. According to the results, SME selectively inhibited proliferation of BeWo cells in-vitro in a dose-dependent manner, but had a lesser effect on HEK 293 cells. SME also suppressed the migration and tube formation of HUVEC cells in-vitro. In addition, SME was able to suppress VEGF-induced angiogenesis in the chorio allantoic membrane, rat cornea, and tumor induced angiogenesis in the peritoneum of EAT bearing mice. A decrease in the microvessel density count and CD31 antigen staining of treated mice peritoneum provided further evidence of its angiosuppressive activity.

CONCLUSIONS

Altogether, the data underline that VEGF mediated angiogenesis is the target for the angiosuppressive action of SME and could potentially be useful in cancer prevention or treatment involving stimulated angiogenesis.

Synthesis and bioactivity of diketopiperazine PJ147 and its derivatives from Gliocladium sp. YUP08

Concise total synthesis of diketopiperazine PJ147, obtained from mycelium of Gliocladium sp. YUP08, has been achieved in seven steps with 43.5% overall yield. Biological evaluation of PJ147 exhibited strong inhibiting activity against A375-S2, Hela, P388, A-549, HL-60, and BEL-7420 cell lines. Thus, eight derivatives of PJ147 with high water solubility were also synthesized to facilitate the in vivo bioassay of this kind of diketopiperazines.

Synthesis of novel heterocyclic ring-fused 18β-glycyrrhetinic acid derivatives with antitumor and antimetastatic activity

Glycyrrhetinic acid (GA) is one of the most important triterpenoic acids shows many pharmacological effects, especially antitumor activity. GA triggers apoptosis in various tumor cell lines. However, the antitumor activity of GA is weak, thus the synthesis of new synthetic analogs with enhanced potency is needed. By introducing various five-member fused heterocyclic rings at C-2 and C-3 positions, 18 novel GA derivatives were obtained. These compounds were evaluated for their inhibitory activity against the growth of eight different tumor cell lines using a SRB assay. The most active compound 37 showed IC50 between 5.19 and 11.72 μm, which was about 11-fold more potent than the lead compound GA. An apoptotic effect of GA and 37 was determined using flow cytometry and trypan blue exclusion assays. We also demonstrated here for the first time that GA and the synthetic derivatives exhibited inhibitory effect on migration of the tested tumor cells, especially 37 which was about 20-fold more potent than GA on antimetastatic activity.

Synthesis and in vitro antineoplastic evaluation of silver nanoparticles mediated by Agrimoniae herba extract

A rapid synthesis of silver nanoparticles (AgNPs) using Agrimoniae herba extract as reducing agent and stabilizer (A. herba-conjugated AgNPs [AH-AgNPs]) were designed, characterized, and evaluated for antitumor therapy feasibility. In this study, critical factors in the preparation of silver nanoparticles, including extraction time, reaction temperature, the concentration of AgNO₃, and A. herba extract amount, were investigated using ultraviolet-visible spectroscopy. AH-AgNPs with well-defined spherical shape, homogeneous distributional small size (30.34 nm), narrow polydispersity index (0.142), and high negative zeta potential (−36.8 mV) were observed by transmission electron microscopy and dynamic light scattering. Furthermore, the results of X-ray diffraction and Fourier-transform infrared spectroscopy further indicated successful preparation of AH-AgNPs. Acceptable long-term storage stability of AH-AgNPs was also confirmed. More importantly, AH-AgNPs displayed significantly higher antiproliferative effect against a human lung carcinoma cell line (A549 cells) compared with A. herba extract and bare AgNPs prepared by sodium citrate. The half-maximal inhibitory concentrations of AH-AgNPs, bare AgNPs, and A. herba extract were 38.13 μg · mL⁻¹, 184.87 μg · mL⁻¹, and 1.147 × 10⁴ μg · mL⁻¹, respectively. It is suggested that AH-AgNPs exhibit a strong antineoplastic effect on A549 cells, pointing to feasibility of antitumor treatment in the future.

Autoimmunity as a double agent in tumor killing and cancer promotion

Cancer immunotherapy through manipulation of the immune system holds great potential for the treatment of human cancers. However, recent trials targeting the negative immune regulators cytotoxic T-lymphocyte antigen 4, programed death 1 (PD-1), and PD-1 receptor ligand (PD-L1) demonstrated that clinically significant antitumor responses were often associated with the induction of autoimmune toxicity. This finding suggests that the same immune mechanisms that elicit autoimmunity may also contribute to the destruction of tumors. Given the fact that the immunological identity of tumors might be largely an immunoprivileged self, autoimmunity may not represent a wholly undesirable outcome in the context of cancer immunotherapy. Rather, targeted killing of cancer cells and autoimmune damage to healthy tissues may be intricately linked through molecular mechanisms, in particular inflammatory cytokine signaling. On the other hand, since chronic inflammation is a well-recognized condition that promotes tumor development, it appears that autoimmunity can be a "double agent" in mediating either pro-tumor or antitumor effects. This review surveys the tumor-promoting and tumoricidal activities of several prominent cytokines: IFN-γ, TNF-α, TGF-β, IL-17, IL-23, IL-4, and IL-13, produced by three major subsets of T helper cells that interact with innate immune cells. Many of these cytokines exert divergent and seemingly contradictory effects on cancer development in different human and animal models, suggesting a high degree of context dependence in their functions. We hypothesize that these inflammatory cytokines could mediate a feedback loop of autoimmunity, antitumor immunity, and tumorigenesis. Understanding the diverse and paradoxical roles of cytokines from autoimmune responses in the setting of cancer will advance the long-term goal of improving cancer immunotherapy, while minimizing the hazards of immune-mediated tissue damage and the possibility of de novo tumorigenesis, through proper monitoring and preventive measures.

Antitumor and immunomodulatory effects of low-dose 5-FU on hepatoma 22 tumor-bearing mice

Low-dose 5-fluorouracil (5-FU), a widely used chemotherapeutic, has been reported to have immunomodulatory effects. This study aimed to evaluate the optimal dose of 5-FU that produces antitumor and immunomodulatory effects. In a hepatoma 22 tumor-bearing mouse model, 0, 10, 20 and 40 mg/kg 5-FU (i.p.) was administered for 10 days. Tumor weight and volume were measured, thymus index (TI) and spleen index (SI) were calculated, and the number of white blood cells (WBCs) and lymphocytes (LYs) were counted following treatment. The percentages of CD3⁺, CD4⁺, CD8⁺ and natural killer (NK) cells were measured by flow cytometry. In addition, the body weights of the mice were measured and the average diet consumption was calculated. Administration of 5-FU produced a potent antitumor effect in a dose-dependent manner (P<0.01). At 20 and 40 mg/kg, a significant reduction of body weight and food consumption was observed. TI and SI decreased in the 20- and 40-mg/kg groups (P<0.01) for 10 days. The number of WBCs significantly decreased in each group (P<0.01); however, the number of LYs only decreased in the 40-mg/kg group (P<0.01). Percentages of CD3⁺ and CD4⁺ cells were increased in the 10- and 20-mg/kg groups (P<0.01). Thus, 5-FU at 10 mg/kg inhibits tumor growth while maintaining the immune function of the mice. 5-FU may exert its antitumor effect at a low dose with low toxicity and stimulate the host immune system. Future clinical trials taking into account the immunostimulatory capacity of chemotherapeutic agents are desirable for certain patients.

A chemoinformatics approach to the discovery of lead-like molecules from marine and microbial sources en route to antitumor and antibiotic drugs

The comprehensive information of small molecules and their biological activities in the PubChem database allows chemoinformatic researchers to access and make use of large-scale biological activity data to improve the precision of drug profiling. A Quantitative Structure-Activity Relationship approach, for classification, was used for the prediction of active/inactive compounds relatively to overall biological activity, antitumor and antibiotic activities using a data set of 1804 compounds from PubChem. Using the best classification models for antibiotic and antitumor activities a data set of marine and microbial natural products from the AntiMarin database were screened-57 and 16 new lead compounds for antibiotic and antitumor drug design were proposed, respectively. All compounds proposed by our approach are classified as non-antibiotic and non-antitumor compounds in the AntiMarin database. Recently several of the lead-like compounds proposed by us were reported as being active in the literature.

Thioester Bonds of Thiocoraline Can Be Replaced with NMe-Amide Bridges without Affecting Its DNA-Binding Properties

In the search for new drug candidates for DNA recognition, affinity and sequence selectivity are two of the most important features. NMe-azathiocoraline, a synthetic antitumor bisintercalator derived from the natural marine product thiocoraline, shows similar potency to the parent compound, as well as possessing enhanced stability. Analysis of the DNA-binding selectivity of NMe-azathiocoraline by DNase I footprinting using universal substrates with all 136 tetranucleotides and all possible symmetrical hexanucleotide sequences revealed that, although this ligand binds to all CpG steps with lower affinities than thiocoraline, it displays additional binding to AT-rich sites. Moreover, fluorescence melting studies showed a strong interaction of the synthetic molecule with CACGTG and weaker binding to ACATGT and AGATCT. These findings demonstrate that NMe-azathiocoraline has the same mode of action as thiocoraline, mimicking its DNA-binding selectivity despite the substitution of its thioester bonds by NMe-amide bridges.

Synthesis and biological evaluation of novel podophyllotoxin analogs as antitumor agents

A series of 4β N-indole-substituted podophyllotoxin derivatives were synthesized. Nine target compounds were evaluated against human cancer cell lines (HeLa, K562, and K562/A02) using MTT assay including three imine derivatives 8, 9, and 10 in vitro. The result showed that the three compounds had higher antitumor activity than their reduced forms. Among them, compounds 8, 9, 11, and 16 were superior to the positive control VP-16.

Inhibitory effects of human lactoferrin on U14 cervical carcinoma through upregulation of the immune response

Human lactoferrin (hLF) is a multifunctional glycoprotein that inhibits cancer growth. However, the inhibitory effect of this glycoprotein in cervical cancer remains inconclusive. This study investigated the efficacy of hLF on the inhibition of U14 cervical cancer in vivo. Recombinant adenovirus carrying hLF (Ad-hLF) were constructed. Mice inoculated with U14 cells were randomly allocated to four treatments: i) Phosphate-buffered saline (negative control), ii) Ad-green fluorescent protein (negative control), iii) Ad-hLF (studied) or iv) cyclophosphamide (CTX; positive control). Tumor growth, as well as levels of natural killer (NK) cells, CD4⁺ and CD8⁺ peripheral blood T lymphocyte subpopulations, serum cytokines and vascular endothelial growth factor (VEGF) in tumor tissues were detected. Compared with the negative controls, tumor growth was inhibited by hLF and mice lifespans in the Ad-hLF-treated group were prolonged to reach the levels of the CTX-treated group. The activity of tumor-killing NK cells was upregulated by hLF. Moreover, the number of CD4⁺ and CD8⁺ peripheral blood T lymphocyte subpopulations increased following treatment with Ad-hLF. Treatment with Ad-hLF increased the levels of serum interferon-γ, serum interleukin-2 (IL-2) and tumor necrosis factor-α, and decreased the levels of serum IL-4 in tumor-bearing mice. The expression of VEGF in tumor tissues was downregulated by hLF. In conclusion, hLF inhibits the growth of U14 solid tumors by modulating the immune response of tumor-bearing mice.

Improving aqueous solubility and antitumor effects by nanosized gambogic acid-mPEG₂₀₀₀ micelles

The clinical application of gambogic acid, a natural component with promising antitumor activity, is limited due to its extremely poor aqueous solubility, short half-life in blood, and severe systemic toxicity. To solve these problems, an amphiphilic polymer-drug conjugate was prepared by attachment of low molecular weight (ie, 2 kDa) methoxy poly(ethylene glycol) methyl ether (mPEG) to gambogic acid (GA-mPEG₂₀₀₀) through an ester linkage and characterized by ¹H nuclear magnetic resonance. The GA-mPEG₂₀₀₀ conjugates self-assembled to form nanosized micelles, with mean diameters of less than 50 nm, and a very narrow particle size distribution. The properties of the GA-mPEG₂₀₀₀ micelles, including morphology, stability, molecular modeling, and drug release profile, were evaluated. MTT (3-(4,5-dimethylthiazo l-2-yl)-2,5 diphenyl tetrazolium bromide) tests demonstrated that the GA-mPEG₂₀₀₀ micelle formulation had obvious cytotoxicity to tumor cells and human umbilical vein endothelial cells. Further, GA-mPEG₂₀₀₀ micelles were effective in inhibiting tumor growth and prolonged survival in subcutaneous B16-F10 and C26 tumor models. Our findings suggest that GA-mPEG₂₀₀₀ micelles may have promising applications in tumor therapy.

Intranasal immunization with recombinant Lactococci carrying human papillomavirus E7 protein and mouse interleukin-12 DNA induces E7-specific antitumor effects in C57BL/6 mice

The use of Lactococcus lactis for the co-delivery of antigens and cytokines has been shown to successfully induce a special immune response. However, it is unknown whether the same results may be triggered through immunization of animals with L. lactis simultaneously carrying protein antigen and cytokine DNA. The present study evaluated the protective effects of intranasally administered live L. lactis strains carrying human papillomavirus 16 E7 protein and murine interleukin-12 (IL-12) DNA (LL-E7_P-IL-12_D) in a TC-1 tumor animal model. C57BL/6 mice were intranasally immunized with recombinant lactococci, and assays for cytotoxicity measurement and tumor protection were carried out to assess the immunological effects of the vaccine candidates. IL-12 and interferon-γ serum levels were measured and immunization with LL-E7_P-IL-12_D was shown to induce an E7-specific immune response and to confer protection against TC-1-induced tumors in vivo. Mice in the LL-E7P-IL-12D group showed an 80% survival rate when the control mice had died. Therapeutic immunization with recombinant L. lactis strains 7 days after TC-1 injection led to a reduction in the number of palpable tumors in treated mice. The antitumor effects of the vaccination occurred through an E7-specific cytotoxic T-lymphocyte response. In the present study, the use of a single L. lactis strain, to co-administer protein antigen and adjuvant DNA, successfully induced an antigen-specific immune response. These observations demonstrate a new strategy for the use of L. lactis as a delivery vector of therapeutic molecules and antigens.

Gracilaria edulis extract induces apoptosis and inhibits tumor in Ehrlich ascites tumor cells in vivo

BACKGROUND

Marine environment is inestimable for their chemical and biological diversity and therefore is an extraordinary resource for the discovery of new anticancer drugs. Recent development in elucidation of the mechanism and therapeutic action of natural products helped to evaluate for their potential activity.

METHODS

We evaluated Gracilaria edulis J. Ag (Brown algae), for its antitumor potential against the Ehrlich ascites tumor (EAT) in vivo and in vitro. Cytotoxicity evaluation of Ethanol Extract of Gracilaria edulis (EEGE) using EAT cells showed significant activity. In vitro studies indicated that EEGE cytotoxicity to EAT cells is mediated through its ability to produce reactive oxygen species (ROS) and therefore decreasing intracellular glutathione (GSH) levels may be attributed to oxidative stress.

RESULTS

Apoptotic parameters including Annexin-V positive cells, increased levels of DNA fragmentation and increased caspase-2, caspase-3 and caspase-9 activities indicated the mechanism might be by inducing apoptosis. Intraperitoneally administration of EEGE to EAT-bearing mice helped to increase the lifespan of the animals significantly inhibited tumor growth and increased survival of mice. Extensive hematology, biochemistry and histopathological analysis of liver and kidney indicated that daily doses of EEGE up to 300 mg/kg for 35 days are well tolerated and did not cause hematotoxicity nor renal or hepatotoxicity.

CONCLUSION

Comprehensive antitumor analysis in animal model and in Ehrlich Ascites Tumor cells was done including biochemical, and pathological evaluations indicate antitumor activity of the extract and non toxic in vivo. It was evident that the mechanism explains the apoptotic activity of the algae extract.

Antitumor and Wound Healing Properties of Rubus ellipticus Smith

The present investigation has been undertaken to study the antioxidant, antitumor, and wound healing properties of Rubus ellipticus. The R. ellipticus leaves were extracted using organic solvents in Soxhlet and were subjected to in vitro antioxidant assays. R. ellipticus leaf methanol (RELM) extract, which showed higher in vitro antioxidant activity, was taken for the evaluation of in vivo antioxidant, antitumor, and wound healing properties. Acute oral and dermal toxicity studies showed the safety of RELM up to a dose of 2 g/kg. A significant wound healing property was observed in incision, excision, and Staphylococcus aureus-induced infected wound models in the treatment groups compared to the control group. A complete epithelialization period was noticed during the 13(th) day and the 19(th) day. A 250-mg/kg treatment was found to prolong the life span of mice with Ehrlich ascite carcinoma (EAC; 46.76%) and to reduce the volume of Dalton's lymphoma ascite (DLA) solid tumors (2.56 cm(3)). The present study suggests that R. ellipticus is a valuable natural antioxidant and that it is immensely effective for treating skin diseases, wounds, and tumors.

Study on anti-osteosarcoma activity of ethanol extract of Venenum bufonis in vitro

BACKGROUND

Venenum bufonis is the dried white secretion of the auricular and skin glands of Bufo gargarizans Cantor, or Bufo melanostictus Schneider, Bufonidae. It is used in the treatment of deep-rooted carbuncle, boils and swelling; pain in the throat, heart stroke, coma, abdominal pain, vomiting and diarrhea. The objective of this paper is to preliminarily observe the effects of ethanol extract of Venenum bufonis on growth, and proliferation of human osteosarcoma U2OS cell lines, and to provide a theoretical basis for an in-depth study of the clinical application of Venenum bufonis for osteosarcoma inhibition, with its mechanism of action.

MATERIALS AND METHODS

SRB assay was used to determine the effect of Venenum bufonis ethanol extract on U2OS cell line activity, and to detect its inhibitory dose-effect on osteosarcoma cells. FCM was applied to determine the effect of Venenum bufonis ethanol extract on U2OS cell apoptosis and to perform cell cycle analysis.

RESULTS

As results, different Venenum bufonis ethanol extracts showed apparent concentration-effect relationships on U2OS cell lines. FCM analysis showed that it had a U2OS apoptosis promoting effect, which increased with increasing concentration. Cell cycle analysis revealed that the Venenum bufonis ethanol extract mainly arrested U2OS in the G0/G1 phase, preventing the cells from progressing to the S phase.

CONCLUSION

The study concluded that Venenum bufonis ethanol extract has an inhibitory effect on proliferation of osteosarcoma U2OS cells.

Current scenario of peptide-based drugs: the key roles of cationic antitumor and antiviral peptides

Cationic antimicrobial peptides (AMPs) and host defense peptides (HDPs) show vast potential as peptide-based drugs. Great effort has been made in order to exploit their mechanisms of action, aiming to identify their targets as well as to enhance their activity and bioavailability. In this review, we will focus on both naturally occurring and designed antiviral and antitumor cationic peptides, including those here called promiscuous, in which multiple targets are associated with a single peptide structure. Emphasis will be given to their biochemical features, selectivity against extra targets, and molecular mechanisms. Peptides which possess antitumor activity against different cancer cell lines will be discussed, as well as peptides which inhibit virus replication, focusing on their applications for human health, animal health and agriculture, and their potential as new therapeutic drugs. Moreover, the current scenario for production and the use of nanotechnology as delivery tool for both classes of cationic peptides, as well as the perspectives on improving them is considered.

Flavonoid-metal ion complexes: a novel class of therapeutic agents

Flavonoids are among the most investigated phytochemicals due to their pharmacological and therapeutic activities. Their ability to chelate with metal ions has resulted in the emergence of a new category of molecules with a broader spectrum of pharmacological activities. However, the biological significance of these flavonoid-metal ion complexes is yet to be completely explored. Moreover, no concerted efforts have been made to elucidate their molecular targets and mechanisms of action. This review attempts to provide a snapshot of the various biological activities reported for flavonoid-metal ion complexes and their potential as therapeutic agents. Understanding the mechanism of action and the influence of structure will provide a strong basis to design novel flavonoid-metal ion complexes of therapeutic significance.

Novel Gemini vitamin D3 analogs: large structure/function analysis and ability to induce antimicrobial peptide

We have synthesized 39 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] analogs having two side chains attached to carbon-20 (Gemini) with various modifications and compared their anticancer activities. Five structure-function rules emerged to identify analogs with enhanced anticancer activity. One of these active analogs, BXL-01-0126, was more potent than 1,25(OH)2D3 in mediating 50% clonal inhibition of cancer cell growth. Murine studies found that BXL-01-0126 and 1,25(OH)2D3 had nearly the same potency to raise serum calcium levels. Taken together, BXL-01-0126 when compared to 1,25(OH)2D3 has greater anticancer potency, but similar toxicity causing hypercalcemia. We focused on the effect of these compounds on the stimulation of expression of human cathelicidin antimicrobial peptide (CAMP) whose gene has a vitamin D response element in its promoter. Expression of CAMP mRNA and protein increased in a dose-response fashion after exposure of acute myeloid leukemia (AML) cells to the Gemini analog, BXL-01-126, in vitro. A xenograft model of AML was developed using U937 AML cells injected into NSG-immunodeficient mice. Administration of vitamin D3 compounds to these mice resulted in substantial levels of CAMP in the systemic circulation. This suggests a unique prophylactic treatment at diagnosis or during induction chemotherapy for AML patients to provide them with protection against various microbial infections through CAMP induction.

Medicinal potential of Morella serata (Lam.) Killick (Myricaceae) root extracts: biological and pharmacological activities

BACKGROUND

Morella serata is a South African medicinal plant used in the treatment of microbial infections and to enhance male sexual performance. There is dearth of information in scientific literature on its efficacy and safety.

METHODS

In the present study, the root extracts were investigated for the phytochemicals that may be present the antibacterial, anticandida activity using 96 wells microtitre plate method and cytotoxicity using brine shrimp (Artemia salina) lethality assay.

RESULTS

The qualitative phytochemical screening revealed the presence of tannins, saponins, flavonoids, terpenoids and steroids. All the extracts including water inhibited both Gram positive and Gram negative bacteria strains at minimum inhibitory concentrations (MIC) ranging from 0.09 - 6.25 mgmL-1. The best activity was observed in the acetone extract inhibiting all the bacteria tested at MIC range of 0.09 - 0.78 mgmL-1 except Shigella flexneri KZN that was inhibited at 1.56 mgmL-1. Similarly, all the extracts suppressed the growth of all Candida species and Trichophyton mucoides at MIC ranging from 0.13 - 3.13 mgmL-1. The cytotoxicity assay revealed potent cytotoxic potential of M. serata methanol and ethanol root extracts by displaying LC50 of 0.26 and 0.18 μgmL-1 respectively.

CONCLUSION

The results obtained from the present study indicated broad spectrum antimicrobial activity and justifies the use of the plant in the treatment of infectious diseases. Also the species could be a good natural source of antitumor compounds considering its lethality against brine shrimp nauplii.

Antitumor, Analgesic, and Anti-inflammatory Activities of Synthesized Pyrazolines

Nitrogen heterocyclic compounds such as pyrazolines have been found to possess a broad spectrum of biological activities such as anticancer, antitubercular, anti-inflammatory, analgesic, and antidepressant activities. Pyrazoline derivatives IV, V (a–e) have been synthesized from the intermediate chalcones III (a–h) by cyclizing with phenyl hydrazine and hydrazine hydrate. The structures of these compounds were confirmed by IR, NMR, and mass spectroscopy. Biological studies of the synthesized compounds showed promising antitumor, analgesic, and anti-inflammatory activities. The compounds were tested for their in vitro antitumor activity against EAC tumor cell lines. Compounds IVa and IVb showed the highest cytotoxicity of 80% at a 200 μg mL concentration. Among the tested compounds, IVa and Vd seem to be more effective analgesic agents. Compounds IVc, IVd, and Ve are found to be the most effective anti-inflammatory agents. Thus the results show that synthesized compounds possess antitumor, analgesic, and anti-inflammatory activity. It was observed that the test compounds with electron withdrawing groups (halogens) on the aromatic ring favors antitumor, analgesic, and anti-inflammatory activity.

Design and synthesis of a tetrahydroisoquinoline-based hydroxamate derivative (ZYJ-34v), an oral active histone deacetylase inhibitor with potent antitumor activity

In our previous study, we developed a novel series of tetrahydroisoquinoline-based hydroxamic acid derivatives as histone deacetylase inhibitors (Bioorg Med Chem, 2010, 18, 1761-1772; J Med Chem, 2011, 54, 2823-2838), among which, compound ZYJ-34c (1) was identified and validated as the most potent one with marked in vitro and in vivo antitumor potency (J Med Chem, 2011, 54, 5532-5539.). Herein, further modification in 1 afforded another oral active analog ZYJ-34v (2) with simplified structure and lower molecular weight. Biological evaluation of compound 2 showed efficacious inhibition against histone deacetylase 1, 2, 3, and 6, which was confirmed by Western blot analysis results. Most importantly, compound 2 exhibited similar even more potent in vitro and in vivo antitumor activities relative to the approved histone deacetylase inhibitor SAHA.

Chemopreventive efficacy of Aegle marmelos on murine transplantable tumors

Emerging trends for cancer chemotherapy show promising developments with the better understanding of molecules delivering more potent and powerful capabilities. But these are severely limited because of increased side effects and higher probability of tumor recurrence. In this scenario, putative exploration of the indigenous and untapped resources modulating immune system to deliver adequate but potent chemopreventive effects appeals considerable interest. However, these require rigorous scientific validation with regard to potency compared with the existing drugs. Aegle marmelos (Linnaeus) Correa (family Rutaceae), a plant component of polyherbal formulation, Indukantha Ghritha, is known for its widespread medicinal values. But the chemopreventive potential has not been explored in comparison to existing anticancer agents. Our attempt contributes the scientific evidence for beneficial immunoprophylactic and antitumor functions in mice challenged with ascites tumors, Dalton's lymphoma ascites, and Ehrlich's ascites carcinoma either alone or in combination with cyclophosphamide and 5-fluorouracil. Specifically, the petroleum ether extracts of this plant (AM(PE)) prophylactically activated a cascade of host defense mechanisms by stimulating or restoring total white blood cell count, macrophage phagocytosis, hematopoiesis, lymphocyte proliferation and functions (CD4+ and CD8+) either naturally or under conditions of impaired immunity like in ascites tumor or during standard agent chemotherapy. Overall, AM(PE) also elicited strong antitumor effects by increasing median survival time and life span, while reducing murine ascites tumor volume and viable tumor counts on par with cyclophosphamide and 5-fluorouracil especially when administered prophylactically. This study also identified 2 putative components, xanthorrhizol and marmelosin, which could be imparting the immunoprophylactic and antitumor effects in transplantable tumor models. Thus, our attempts provide sufficient proof to warrant further to test this drug in higher animal models or in patients with high risk for tumor recurrence and/or immunocompromised diseases.

Characterization and evaluation of an oral microemulsion containing the antitumor diterpenoid compound ent-11alpha-hydroxy-15-oxo-kaur-16-en-19-oic-acid

The objective of this study was to develop an oral microemulsion formulation of the antitumor diterpenoid agent, ent-11α-hydroxy-15-oxo-kaur-16-en-19-oic-acid (henceforth referred to as 5F), to enhance its bioavailability and evaluate its hepatotoxicity. Pseudoternary phase diagrams showed that the optimal microemulsion formulation contained 45% water, 10% castor oil as the oil phase, 15% Cremophor EL as the surfactant, and 30% as a cosurfactant mixture of 1,2-propanediol and polyethylene glycol (PEG)-400 (2:1, w/w). The microemulsion preparation was characterized and its droplet diameter was within 50 nm. Release of 5F in vitro from the microemulsion was slightly increased compared with a suspension containing the same amount of active drug. Pharmacokinetic parameters in vivo indicated that bioavailability was markedly improved, with the relative bioavailability being 616.15% higher for the microemulsion than for the suspension. Toxicity tests showed that the microemulsion had no hepatotoxicity in mice. These results suggest the potential for 5F microemulsion to be administered by the oral route.

Isolation and characterization of muscle fatigue substance with anti-tumor activities

Research during the 1950's indicated that exercise played a role in the reduction of tumor growth. In the 1960's our studies confirmed that tumor-bearing rats, exercised to fatigue, demonstrated tumor inhibition. Our further studies isolated an extract (Fatigue Substance, or F-Substance) from rectus femoris muscles of rats which had been electrically stimulated to fatigue. This extract significantly inhibited growth of transplanted rat tumors. Research continued until 1978 when it became apparent the methodology at that time was not able to further identify the substance's active components. Using current technology, we now report on the further isolation and characterization of F-Substance. In cell proliferation assays, extracts from electrically stimulated rat rectus femoris muscles had more significant inhibitory effect on the breast cancer cell line MCF-7 than those isolated from unstimulated muscles. To identify the molecule(s) responsible for the antitumor activity, a rat cytokine antibody array was used to profile the cytokines in the substances. Among the 29 different cytokines contained on the array, 3 showed greater than 3-fold difference between the substances isolated from the stimulated and unstimulated muscles. LIX (also known as CXCL5) is 6-fold higher in the substances isolated from stimulated muscles than those from the unstimulated muscles. TIMP-1 is 4.6 fold higher and sICAM is 3.6 fold higher in the substances from the stimulated muscles. Our results indicated that cytokines released from contracting muscles might be responsible for the antitumor effect of F-Substance.

Review of the medicinal effects of tualang honey and a comparison with manuka honey

Tualang honey (TH) is a Malaysian multifloral jungle honey. In recent years, there has been a marked increase in the number of studies published in medical databases regarding its potential health benefits. The honey is produced by the rock bee (Apis dorsata), which builds hives on branches of tall Tualang trees located mainly in the north-western region of Peninsular Malaysia. This review collates the results of the various studies of TH that range from research on tissue culture to randomised control clinical trials. Findings thus far show that, TH has antimicrobial, anti-inflammatory, antioxidant, antimutagenic, antitumor, and antidiabetic properties, in addition to wound-healing attributes. Some of its properties are similar to the well-researched Manuka honey (New Zealand and/or Australian monofloral honey). Distinct differences include higher phenolics, flavonoids, and 5-(hydroxymethyl) furfural (HMF). Compared with Manuka honey, TH is also more effective against some gram-negative bacterial strains in burn wounds.

One-channel double stent implantation for hilar biliary obstructions

The aim of this study was to evaluate the effect of percutaneous one-channel double stent implantation on hilar biliary obstruction involving both hepatic ducts and its clinical value. A total of 8 patients with hilar biliary obstruction involving the left and right hepatic ducts were enrolled. A percutaneous unilateral approach was adopted. Two stents were implanted, one between the left and right hepatic ducts and the other between the hepatic ducts and the common bile duct for biliary drainage. Interventional therapies such as arterial chemoembolization were performed for antitumor treatment. All surgical procedures were successfully accomplished. At 2 weeks after stenting, total bilirubin decreased to 61.2±13.4 μmol/l (the preoperative value was 267.1±154.7 μmol/l). No severe complications or mortalities occurred. Single-channel double stent implantation should be the preferred method of treatment for patients with hilar biliary obstruction involving both hepatic ducts. Drainage and antitumor treatment should also be used when necessary.

Gemcitabine-loaded albumin nanospheres (GEM-ANPs) inhibit PANC-1 cells in vitro and in vivo

With the development of nanotechnology, special attention has been given to the nanomaterial application in tumor treatment. Here, a modified desolvation-cross-linking method was successfully applied to fabricate gemcitabine-loaded albumin nanospheres (GEM-ANPs), with 110 and 406 nm of mean diameter, respectively. The aim of this study was to assess the drug distribution, side effects, and antitumor activity of GEM-ANPs in vivo. The metabolic viability and flow cytometry analysis revealed that both GEM-ANPs, especially 406-nm GEM-ANPs, could effectively inhibit the metabolism and proliferation and promote the apoptosis of human pancreatic carcinoma (PANC-1) in vitro. Intravenous injection of 406-nm GEM-ANPs exhibited a significant increase of gemcitabine in the pancreas, liver, and spleen of Sprague-Dawley rats (p < 0.05). Moreover, no signs of toxic side effects analyzed by blood parameter changes were observed after 3 weeks of administration although a high dose (200 mg/kg) of GEM-ANPs were used. Additionally, in PANC-1-induced tumor mice, intravenous injection of 406-nm GEM-ANPs also could effectively reduce the tumor volume by comparison with free gemcitabine. With these findings, albumin nanosphere-loading approach might be efficacious to improve the antitumor activity of gemcitabine, and the efficacy is associated with the size of GEM-ANPs.

Effect of Paris saponin on antitumor and immune function in U14 tumor-bearing mice

We evaluated the effect of Paris saponin on inhibition of cervical cancer in mice and on immune regulation in tumor-bearing mice. MTT assay was used to examine the effect of Paris saponin on U14 cell proliferatiosn in vitro; the ascites tumor model of U14 cervical cancer was established to observe the effect of Paris saponin on inhibition of the tumor and on survival time of mice; and serum IL-4 and IFN-γ levels in tumor-bearing mice were detected. The Paris saponin showed significant inhibitory effect on growth of cervical cancer U14 cells both in vitro and in vivo, prolonged the survival time of mice, increased the serum IFN-γ level of tumor-bearing mice, and reduced the serum IL-4 level. The Paris saponin can inhibit U14 cell growth and prolong survival time of mice; it is speculated that the Paris saponin may express its anti-tumor activity by improving the body's immune system.

Cytotoxic effect of the ethanolic extract of Lophocereus schottii: a Mexican medicinal plant

Lophocereus schottii is a Mexican cactus known as garambullo whose bark is used for the treatment of cancer, diabetes, ulcers, sores, stomach disorders and tuberculosis. The aim of this study was to evaluate the cytotoxic effect of the ethanolic extract of bark of L. Schottii. To assess these effects we established a flow of experiments in a model of BALB/c mice murine lymphoma. We value first survival of mice inoculated with 2 × 10(4) L5178Y murine lymphoma cells, orally treated with 10 mg/Kg of the extract for 10 consecutive days; the second assessment was to determine the influence of the immune system, we carry out studies of lymphoproliferation in mice with the same conditions of the previous study, only that the treatment was for 22 days before the completion cell cultures; the third study was to establish the cytotoxic effect of extract of L. schottii using different concentrations, by murine lymphoma cell cultures and splenocytes from healthy mice and finally we assessed the effect in vivo of extract of L. Schottii in a model of solid murine lymphoma inoculating 1 × 10(7) lymphoma cells in the gastrocnemius muscle observing the development of the tumor. We observed that oral treatment of 10 mg/kg of extract of L. schottii increased survival rate in treated mice; additionally, an intratumoral injection of 50 and 100 mg/kg in a solid murine lymphoma located in the gastrocnemius muscle, allowed a significantly slower tumor evolution. In vitro studies determined that extract inhibited 63% of lymphoma cell growth. With these evidences it is feasible to scientifically validate that ethanolic extract of L. schottii had an effect on L5178Y murine cells lymphoma and could have the same effect in human tumors.

Antitumor activity of bacterial exopolysaccharides from the endophyte Bacillus amyloliquefaciens sp. isolated from Ophiopogon japonicus

The endophytic bacterium, MD-b1, was isolated from the medicinal plant Ophiopogon japonicas and identified as the Bacillus amyloliquefaciens sp. with 99% similarity based on the partial sequence analysis of 16S rDNA. Exopolysaccharides were extracted from the endophyte for the evaluation of its antitumor activity against gastric carcinoma cell lines (MC-4 and SGC-7901). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays and microscopy were performed to estimate the cell viability and morphological changes of the MC-4 and SGC-7901 cells following treatment with the exopolysaccharides at 14, 22 and 30 μg/μl. The results revealed that the exopolysaccharides displayed concentration-dependent inhibitory effects against the MC-4 and SGC-7901 cells, with an IC₅₀ of 19.7 and 26.8 μg/μl, respectively. The exopolysaccharides also induced morphological abnormalities in the cells. These effects indicated the the exopolysaccharides had an antitumoral mechanism of action associated with the mitochondrial dysfunction of the treated cells. This is the first study to investigate the endophytic microorganism isolated from O. japonicas and also the first discovery of such antitumoral exopolysaccharides derived from the genus Bacillus. This provides a promising and reproducible natural product source with high therapeutic value for anticancer treatment, thereby facilitating the development of new anticancer agents.

Synthesis of 8-hydroxyquinoline derivatives as novel antitumor agents

This letter describes the preparation of quinoline derivatives and their cytotoxic potentials toward human carcinoma cell lines. Among the selected compounds, 8-hydroxy-2-quinolinecarbaldehyde (3) showed the best in vitro cytotoxicity against the human cancer cell lines, including MDA231, T-47D, Hs578t, SaoS2, K562, SKHep1 (with a MTS50 range of 12.5-25 μg/mL) and Hep3B (with a MTS50 range of 6.25±0.034 μg/mL). The in vivo antitumor activity of compound 3 on subcutenaous Hep3B hepatocellular carcinoma xenograft in athymic nude mice was then studied. The results showed that the dose of 10 mg/kg/day of compound 3 with intraperitoneal injection for 9 days totally abolished the growth of the xenograft tumor of Hep3B with no histological damage on vital organs as compared with the control. The experimental results suggested that compound 3 has a good potential as an antitumor agent.

Discovery of the Highly Potent PI3K/mTOR Dual Inhibitor PF-04979064 through Structure-Based Drug Design

PI3K, AKT, and mTOR are key kinases from PI3K signaling pathway being extensively pursued to treat a variety of cancers in oncology. To search for a structurally differentiated back-up candidate to PF-04691502, which is currently in phase I/II clinical trials for treating solid tumors, a lead optimization effort was carried out with a tricyclic imidazo[1,5]naphthyridine series. Integration of structure-based drug design and physical properties-based optimization yielded a potent and selective PI3K/mTOR dual kinase inhibitor PF-04979064. This manuscript discusses the lead optimization for the tricyclic series, which both improved the in vitro potency and addressed a number of ADMET issues including high metabolic clearance mediated by both P450 and aldehyde oxidase (AO), poor permeability, and poor solubility. An empirical scaling tool was developed to predict human clearance from in vitro human liver S9 assay data for tricyclic derivatives that were AO substrates.

The effect-enhancing and toxicity-reducing activity of Hypericum japonicum Thunb. extract in murine liver cancer chemotherapy

Chinese herbs are potential sources of antitumor drugs with immunoregulatory activity and few adverse effects. In the present study, we investigated whether the Hypericum japonicum Thunb. (HJT) extract enhanced the efficacy of 5-fluorouracil (5-FU) treatment in murine liver tumor xenografts and reduced toxicity of chemotherapy in hepatoma H22-bearing mice. Tumor weight and inhibition rate, thymus and spleen indices, as well as white blood cell (WBC) count were calculated. The phagocytic function of macrophages was assessed by observing peritoneal macrophages phagocytized chicken red blood cells (RBC). Body weight and toxic reactions of the chemotherapeutic and life prolongation rate were investigated in the mice. Results demonstrated that the HJT extract significantly enhanced the tumor inhibition rate of 5-FU, improved the immune function, reduced the toxic effects and prolonged the survival time in the tumor-bearing mice. Taken together, these results indicated that the HJT extract has a synergistic tumor-inhibiting effect with 5-FU, is able to reduce the toxic side effects and is likely to be safe and efficacious for use in antitumor therapy.

Structure elucidation, protein profile and the antitumor effect of the biological active substance extracted from sea cucumber Holothuria polii

Holothuria polii (Delle Chiaje, 1823) (Holothuriidae) is a sea cucumber inhabiting Mediterranean Sea coast of Egypt. The bioactive compound of its tegument has antifungal, antibacterial and antiparasitic effects. The present study aims to elucidate the structure of the bioactive material of H. polii for pharmacological and chemotaxonomic purposes. Furthermore, the study demonstrates its efficacy as a cytotoxic agents against two tumor cell lines HCT116 (colon adenocarcinoma cell line) and MCF7 (breast adenocarcinoma cell line). The biological active compound of the ethanol extract has been characterized by means of infrared (IR), proton-nuclear magnetic resonance ((1)H NMR), ultraviolet-visible (UV-Vis) and mass spectra. Protein profile was carried out using sodium dodecyl sulfate polyacrylamide gel electrophoresis. Cytotoxic activity was carried out according to sulforhodamine-B assay. IR, (1)H NMR, UV-Vis and mass spectra showed that the extracted bioactive material is a nonsulfated hexaosides called bivittoside. This glycoside is composed of aglycone and a glycosidic chain (carbohydrate chain) enclosed with six sugar units, including xylose, glucose, 3-O-methylglucose and quinovose. There were no traces of dissolved proteins. The preliminary cytotoxic assay of bivittoside exhibited significant cytotoxic activity against two types of cultured tumor cell lines of HCT116 and MCF7. The half-maximal inhibitory concentration was 17.4 µg/ml and 18 µg/ml for MCF7 and HCT116, respectively. Although H. polii belongs to the genus Holothuria, the lacking of sulfate group and the fact that it contains up to six monosaccharides make it different from this genus. The present study suggests separation of H. polii from its genus to a new one. On the other hand, results support the hypothesis that H. polii bioactive compound has an antitumor effect.

The impact of the Uighur medicine abnormal savda munziq on antitumor and antioxidant activity in a S180 and Ehrlich ascites carcinoma mouse tumor model

Aim:

This study was designed to study the antitumor and antioxidant activity of Uighur medicine abnormal savda munziq (ASMq) in the S180 and Ehrlich ascites carcinoma mice tumor model.

Materials and Methods:

The serum levels of superoxide dismutase (SOD), malonaldehyde (MDA), and glutathione-catalase (GSH-PX) were analyzed, and the mice were also subjected to a hypoxia tolerance test. Their climbing ability was also analyzed.

Results:

The findings of the study revealed that ASMq-treatment leads to an increase in blood serum SOD and GSH-PX levels but a decrease in blood serum MDA levels. Moreover, ASMq-treatment enhanced the survival time of mice maintained under hypoxic conditions and improved their mice climbing ability.

Conclusions:

The results of this study indicate that ASMq has obvious antitumor and antioxidative effects.

Biochemical and pharmacological characterization of human c-Met neutralizing monoclonal antibody CE-355621

The c-Met proto-oncogene is a multifunctional receptor tyrosine kinase that is stimulated by its ligand, hepatocyte growth factor (HGF), to induce cell growth, motility and morphogenesis. Dysregulation of c-Met function, through mutational activation or overexpression, has been observed in many types of cancer and is thought to contribute to tumor growth and metastasis by affecting mitogenesis, invasion, and angiogenesis. We identified human monoclonal antibodies that bind to the extracellular domain of c-Met and inhibit tumor growth by interfering with ligand-dependent c-Met activation. We identified antibodies representing four independent epitope classes that inhibited both ligand binding and ligand-dependent activation of c-Met in A549 cells. In cells, the antibodies antagonized c-Met function by blocking receptor activation and by subsequently inducing downregulation of the receptor, translating to phenotypic effects in soft agar growth and tubular morphogenesis assays. Further characterization of the antibodies in vivo revealed significant inhibition of c-Met activity (≥ 80% lasting for 72-96 h) in excised tumors corresponded to tumor growth inhibition in multiple xenograft tumor models. Several of the antibodies identified inhibited the growth of tumors engineered to overexpress human HGF and human c-Met (S114 NIH 3T3) when grown subcutaneously in athymic mice. Furthermore, lead candidate antibody CE-355621 inhibited the growth of U87MG human glioblastoma and GTL-16 gastric xenografts by up to 98%. The findings support published pre-clinical and clinical data indicating that targeting c-Met with human monoclonal antibodies is a promising therapeutic approach for the treatment of cancer.

In vivo induction of apoptosis by fucoxanthin, a marine carotenoid, associated with down-regulating STAT3/EGFR signaling in sarcoma 180 (S180) xenografts-bearing mice

Previous in vitro researches have showed that fucoxanthin, a natural carotenoid isolated from sargassum, can inhibit proliferation or induce apoptosis in human neuroblastoma, hepatoma, leukemia, colon carcinoma, prostate cancer or urinary bladder cancer cells. But the precise mechanism by which fucoxanthin exerts anticarcinogenic effects is not yet fully understood. In this study, we performed an in vivo study to investigate the anti-tumor effect and mechanisms of fucoxanthin on xenografted sarcoma 180 (S180) in mice. Results revealed that fucoxanthin significantly inhibited the growth of sarcoma at the dose of 50 or 100 mg/kg. TUNEL analysis showed that the number of positive cells in the fucoxanthin-treated group was higher than that in the control group. Western blotting analysis also revealed the suppressed expression of bcl-2 and enhanced expression of cleaved caspase-3 by fucoxanthin. In addition, immunohistochemistry analysis and Western blotting analysis showed that fucoxanthin significantly decreased the expressions of survivin and vascular endothelial growth factor (VEGF). Most importantly, fucoxanthin inhibited the expressions of the epidermal growth factor receptor (EGFR) and STAT3 and phosphorylated STAT3 proteins. These results indicated that in vivo induction of apoptosis by fucoxanthin is associated with down-regulating STAT3/EGFR signaling in S180 xenografts-bearing mice.

Trans,trans,trans-[PtIV(N3)2(OH)2(py)(NH3)]: a light-activated antitumor platinum complex that kills human cancer cells by an apoptosis-independent mechanism

Photoactivatable Pt(IV) diazido complexes have unusual photobiologic properties. We show here that trans,trans,trans-[Pt(IV)(N(3))(2)(OH)(2)(py)(NH(3))] complex 3 is a potent photoactivated cytotoxin toward human cancer cells in culture, with an average IC(50) value in 13 cell lines of 55 ± 28 μmol/L after 30 minutes (0.12 mW/cm(2)) photoactivation with UVA, although visible light was also effective. Photoactivated complex 3 was noncross-resistant to cisplatin in 3 of 4 resistant cell lines. Cell swelling but very little blebbing was seen for HL60 cells treated with irradiated complex 3. Unlike cisplatin and etoposide, both of which cause apoptosis in HL60 cells, no apoptosis was observed for UVA-activated complex 3 by the Annexin V/propidium iodide flow cytotometry assay. Changes in the levels of the autophagic proteins LC3B-II and p62 in HL60 cells treated with UVA-activated complex 3 indicate autophagy is active during cell death. In a clonogenic assay with the SISO human cervix cancer cell line, 3 inhibited colony formation when activated by UVA irradiation. Antitumor activity of complex 3 in mice bearing xenografted OE19 esophageal carcinoma tumors was photoaugmented by visible light. Insights into the novel reaction pathways of complex 3 have been obtained from (14)N{(1)H} nuclear magnetic resonance studies, which show that photoactivation pathways can involve release of free azide in buffered solution. Density functional theory (DFT) and time-dependent DFT calculations revealed the dissociative character of singlet and triplet excited states of complex 3, which gives rise to reactive, possibly cytotoxic azidyl radicals.

Pardaxin, a fish antimicrobial peptide, exhibits antitumor activity toward murine fibrosarcoma in vitro and in vivo

The antitumor activity of pardaxin, a fish antimicrobial peptide, has not been previously examined in in vitro and in vivo systems for treating murine fibrosarcoma. In this study, the antitumor activity of synthetic pardaxin was tested using murine MN-11 tumor cells as the study model. We show that pardaxin inhibits the proliferation of MN-11 cells and reduces colony formation in a soft agar assay. Transmission electron microscopy (TEM) showed that pardaxin altered the membrane structure similar to what a lytic peptide does, and also produced apoptotic features, such as hollow mitochondria, nuclear condensation, and disrupted cell membranes. A qRT-PCR and ELISA showed that pardaxin induced apoptosis, activated caspase-7 and interleukin (IL)-7r, and downregulated caspase-9, ATF 3, SOCS3, STAT3, cathelicidin, p65, and interferon (IFN)-γ suggesting that pardaxin induces apoptosis through the death receptor/nuclear factor (NF)-κB signaling pathway after 14 days of treatment in tumor-bearing mice. An antitumor effect was observed when pardaxin (25 mg/kg; 0.5 mg/day) was used to treat mice for 14 days, which caused significant inhibition of MN-11 cell growth in mice. Overall, these results indicate that pardaxin has the potential to be a novel therapeutic agent to treat fibrosarcomas.

Self-assembling peptide-based nanoparticles enhance anticancer effect of ellipticine in vitro and in vivo

BACKGROUND AND METHODS

Applications of the anticancer agent, ellipticine, have been limited by its hydrophobicity and toxicity. An efficient delivery system is required to exploit the enormous potential of this compound. Recently, EAK16-II, an ionic-complementary, self-assembling peptide, has been found to stabilize ellipticine in aqueous solution. Here, the anticancer activity of ellipticine encapsulated in EAK16-II (EAK-EPT) was evaluated in vitro and in vivo.

RESULTS

Our cellular uptake, toxicity, and apoptosis results in an A549 human lung carcinoma cell line indicate that EAK-EPT complexes are significantly more effective than treatment with EAK16-II or ellipticine alone. This is due to the ability of EAK16-II to stabilize ellipticine in a protonated state in well formed nanostructures approximately 200 nm in size. In vivo observations in an A549 nude mouse tumor model show higher antitumor activity and lower cytotoxicity of EAK-EPT complexes than in the control group treated with ellipticine alone. Tumor growth in animals was significantly inhibited after treatment with EAK-EPT complexes, and without any apparent side effects.

CONCLUSION

The anticancer activity observed in this study coupled with minimal side effects encourages further development of peptide-mediated delivery of anticancer drugs, ellipticine in the present case, for clinical application.

Gene-carried hepatoma targeting complex induced high gene transfection efficiency with low toxicity and significant antitumor activity

Background

The success of gene transfection is largely dependent on the development of a vehicle or vector that can efficiently deliver a gene to cells with minimal toxicity.

Methods

A liver cancer-targeted specific peptide (FQHPSF sequence) was successfully synthesized and linked with chitosan-linked polyethylenimine (CP) to form a new targeted gene delivery vector called CPT (CP/peptide). The structure of CPT was confirmed by ¹H nuclear magnetic resonance spectroscopy and ultraviolet spectrophotometry. The particle size of CPT/ DNA complexes was measured using laser diffraction spectrometry and the cytotoxicity of the copolymer was evaluated by methylthiazol tetrazolium method. The transfection efficiency evaluation of the CP copolymer was performed using luciferase activity assay. Cellular internalization of the CP/DNA complex was observed under confocal laser scanning microscopy. The targeting specificity of the polymer coupled to peptide was measured by competitive inhibition transfection study. The liver targeting specificity of the CPT copolymer in vivo was demonstrated by combining the copolymer with a therapeutic gene, interleukin-12, and assessed by its abilities in suppressing the growth of ascites tumor in mouse model.

Results

The results showed that the liver cancer-targeted specific peptide was successfully synthesized and linked with CP to form a new targeted gene delivery vector called CPT. The composition of CPT was confirmed and the vector showed low cytotoxicity and strong targeting specificity to liver tumors in vitro. The in vivo study results showed that interleukin-12 delivered by the new gene vector CPT/DNA significantly enhanced the antitumor effect on ascites tumor-bearing imprinting control region mice as compared with polyethylenimine (25 kDa), CP, and other controls, which further demonstrate the targeting specificity of the new synthesized polymer.

Conclusion

The synthesized CPT copolymer was proven to be an effective liver cancer-targeted vector for therapeutic gene delivery, which could be a potential candidate for targeted cancer gene therapy.

with covalent conjugation of polyethyelene glycol

Background

Alpha-momorcharin (α-MMC) and momordica anti-HIV protein (MAP30) derived from Momordica charantia L. have been confirmed to possess antitumor and antivirus activities due to their RNA-N-glycosidase activity. However, strong immunogenicity and short plasma half-life limit their clinical application. To solve this problem, the two proteins were modified with (mPEG)₂-Lys-NHS (20 kDa).

Methodology/principal findings

In this article, a novel purification strategy for the two main type I ribosome-inactivating proteins (RIPs), α-MMC and MAP30, was successfully developed for laboratory-scale preparation. Using this dramatic method, 200 mg of α-MMC and about 120 mg of MAP30 was obtained in only one purification process from 200 g of Momordica charantia seeds. The homogeneity and some other properties of the two proteins were assessed by gradient SDS-PAGE, electrospray ionization quadruple mass spectrometry, and N-terminal sequence analysis as well as Western blot. Two polyethylene glycol (PEG)ylated proteins were synthesized and purified. Homogeneous mono-, di-, or tri-PEGylated proteins were characterized by matrix-assisted laser desorption ionization-time of flight mass spectrometry. The analysis of antitumor and antivirus activities indicated that the serial PEGylated RIPs preserved moderate activities on JAR choriocarcinoma cells and herpes simplex virus-1. Furthermore, both PEGylated proteins showed about 60%–70% antitumor and antivirus activities, and at the same time decreased 50%–70% immunogenicity when compared with their unmodified counterparts.

Conclusion/significance

α-MMC and MAP30 obtained from this novel purification strategy can meet the requirement of a large amount of samples for research. Their chemical modification can solve the problem of strong immunogenicity and meanwhile preserve moderate activities. All these findings suggest the potential application of PEGylated α-MMC and PEGylated MAP30 as antitumor and antivirus agents. According to these results, PEGylated RIPs can be constructed with nanomaterials to be a targeting drug that can further decrease immunogenicity and side effects. Through nanotechnology we can make them low-release drugs, which can further prolong their half-life period in the human body.

Quinazolin-4-one coupled with pyrrolidin-2-iminium alkaloids from marine-derived fungus Penicillium aurantiogriseum

Three new alkaloids, including auranomides A and B (1 and 2), a new scaffold containing quinazolin-4-one substituted with a pyrrolidin-2-iminium moiety, and auranomide C (3), as well as two known metabolites auranthine (4) and aurantiomides C (5) were isolated from the marine-derived fungus Penicillium aurantiogriseum. The chemical structures of compounds 1–3 were elucidated by extensive spectroscopic methods, including IR, HRESIMS and 2D NMR spectroscopic analysis. The absolute configurations of compounds 1–3 were suggested from the perspective of a plausible biosynthesis pathway. Compounds 1–3 were subjected to antitumor and antimicrobial screening models. Auranomides A–C exhibited moderate cytotoxic activity against human tumor cells. Auranomides B was the most potent among them with an IC₅₀ value of 0.097 μmol/mL against HEPG2 cells.

A Case Series of Survival Outcomes in Patients with Advanced-stage IIIb/IV Non-small-cell Lung Cancer Treated with HangAm-Plus

BACKGROUND AND OBJECTIVES

Non-small-cell lung cancer (NSCLC) represents approximately 80% of all lung cancers. Unfortunately, at their time of diagnosis, most patients have advanced to unresectable disease with a very poor prognosis. The oriental herbal medicine HangAm-Plus(HAP) has been developed for antitumor purposes, and several previous studies have reported its therapeutic effects. In this study, the efficacy of HAP was evaluated as a third-line treatment for advanced-stage IIIb/IV NSCLC.

METHODS

The study involved six patients treated at the East- West Cancer Center (EWCC) from April 2010 to October 2011. Inoperable advanced-stage IIIb/IV NSCLC patients received 3,000 or 6,000 mg of HAP on a daily basis over a 12-week period. Computed tomography (CT) scans were obtained from the patients at the time of the initial administration and after 12 weeks of treatment. We observed and analyzed the patients overall survival (OS) and progression-free survival (PFS).

RESULTS

Of the six patients, three expired during the study, and the three remaining patients were alive as of October 31, 2011. The OS ranged from 234 to 512 days, with a median survival of 397 days and a one-year survival rate of 66.7%. In the 12-week-interval chest CT assessment, three patients showed stable disease (SD), and the other three showed progressive disease (PD). The PFS of patients ranged from 88 to 512 days, the median PFS being 96 days. Longer OS and PFS were correlated with SD. Although not directly comparable, the OS and the PFS of this study were greater than those of the docetaxel or the best supportive care group in other studies.

CONCLUSION

HAP may prolong the OS and the PFS of inoperable stage IIIb/IV NSCLC patients without significant adverse effects. In the future, more controlled clinical trials with larger samples from multi-centers should be conducted to evaluate the efficacy and the safety of HAP.

Studies on the synthesis of derivatives of marine-derived bostrycin and their structure-activity relationship against tumor cells

A series of new derivatives (5–29) of marine-derived bostrycin (1) were synthesized. The in vitro cytotoxic activities of all compounds were evaluated against MCF-7, MDA-MB-435, A549, HepG2, HCT-116 and MCF-10A cells using the MTT method. The compounds 7, 8, 22, 23, 25, 28 and 29 of the total showed comparable activity to epirubicin, the positive control, against the tested cancer cell lines. However, these compounds also exhibited cytotoxicity towards MCF-10A cells. The structure-activity relationship (SAR) of bostrycin derivatives was also discussed based on the obtained experimental data.

Pre-existing Fas ligand (FasL) in cancer cells elicits tumor-specific protective immunity, but delayed induction of FasL expression after inoculation facilitates tumor formation

Overexpression of Fas ligand (FasL) in cancer cells elicits potential antitumor effects via recruitment of neutrophils. Conversely, FasL-expressing tumors may counterattack tumor-infiltrating lymphocytes by delivering apoptotic death signals via Fas/FasL interactions, which may lead to tumor escape. In order to distinguish the role of FasL in antitumor activity and tumor progression, Lewis lung carcinoma cells (LLC-1) were used to establish the cell line LLC-FasL, in which FasL expression was repressed by doxycycline (Dox) treatment and induced in the absence of Dox. LLC-FasL cells promote tumor regression when expressing FasL, whereas tumor outgrowth is observed by depletion of FasL expression. To investigate whether initial expression of FasL during tumor formation is critical for FasL-mediated tumor regression, Dox-treated LLC-FasL cells were inoculated into Dox-treated mice, but Dox treatment was stopped 5 days after inoculation. When low cell numbers were inoculated, we observed 80% survival and no tumor formation, whereas no mice survived inoculation with high cell numbers, despite the delayed induction of FasL by Dox withdrawal. The inoculation of a high density of cells may establish a favorable tumor microenvironment before the expression of FasL. Our findings demonstrate that FasL may elicit antitumor activity when it is initially present on injected cancer cells and thus can act prior to tumor microenvironment formation. Furthermore, a well-established tumor microenvironment abrogates FasL-mediated antitumor activity.

A Lactose-Binding Lectin from the Marine Sponge Cinachyrella Apion (Cal) Induces Cell Death in Human Cervical Adenocarcinoma Cells

Cancer represents a set of more than 100 diseases, including malignant tumors from different locations. Strategies inducing differentiation have had limited success in the treatment of established cancers. Marine sponges are a biological reservoir of bioactive molecules, especially lectins. Several animal and plant lectins were purified with antitumor activity, mitogenic, anti-inflammatory and antiviral, but there are few reports in the literature describing the mechanism of action of lectins purified from marine sponges to induce apoptosis in human tumor cells. In this work, a lectin purified from the marine sponge Cinachyrella apion (CaL) was evaluated with respect to its hemolytic, cytotoxic and antiproliferative properties, besides the ability to induce cell death in tumor cells. The antiproliferative activity of CaL was tested against HeLa, PC3 and 3T3 cell lines, with highest growth inhibition for HeLa, reducing cell growth at a dose dependent manner (0.5–10 µg/mL). Hemolytic activity and toxicity against peripheral blood cells were tested using the concentration of IC₅₀ (10 µg/mL) for both trials and twice the IC₅₀ for analysis in flow cytometry, indicating that CaL is not toxic to these cells. To assess the mechanism of cell death caused by CaL in HeLa cells, we performed flow cytometry and western blotting. Results showed that lectin probably induces cell death by apoptosis activation by pro-apoptotic protein Bax, promoting mitochondrial membrane permeabilization, cell cycle arrest in S phase and acting as both dependent and/or independent of caspases pathway. These results indicate the potential of CaL in studies of medicine for treating cancer.

Targeted agents for the treatment of metastatic melanoma

In the last year, the armamentarium of melanoma therapeutics has radically changed. Recent discoveries in melanoma biology and immunology have led to novel therapeutics targeting known oncogenes and immunotherapeutic antibodies. Phase III clinical trials of these agents have reported measurable and meaningful benefits to patients with metastatic disease. In this article, we review recent findings and discuss their significance in melanoma therapy. As our understanding of melanoma biology grows, this initial therapeutic success may be enhanced through the use of molecular markers to select patients, and new targeted immunotherapies in sequential or combination drug regimens.

Gelatinase-stimuli strategy enhances the tumor delivery and therapeutic efficacy of docetaxel-loaded poly(ethylene glycol)-poly(ɛ-caprolactone) nanoparticles

Nanoscale drug carriers have been extensively developed to improve drug therapeutic efficiency. However, delivery of chemotherapeutic agents to tumor tissues and cells has not been favorably managed. In this study, we developed a novel “intelligent” nanoparticle, consisting of a gelatinase-cleavage peptide with poly(ethylene glycol) (PEG) and poly(ɛ-caprolactone) (PCL)-based structure for tumor-targeted docetaxel delivery (DOC-TNPs). The docetaxel-loaded PEG-PCL nanoparticles (DOC-NPs) that did not display gelatinase-stimuli behaviors were used as a control. We found clear evidence that the DOC-TNPs were transformed by gelatinases, allowing drug release and enhancing the cellular uptake of DOC (P < 0.01). In vivo biodistribution study demonstrated that targeted DOC-TNPs could accumulate and remain in the tumor regions, whereas non-targeted DOC-NPs rapidly eliminated from the tumor tissues. DOC-TNPs exhibited higher tumor growth suppression than commercialized Taxotere^® (docetaxel; Jiangsu Hengrui Medicine Company, Jiangsu, China) and DOC-NPs on hepatic H22 tumor model via intravenous administration (P < 0.01). Both in vitro and in vivo experiments suggest that the gelatinase-mediated nanoscale delivery system is promising for improvement of antitumor efficacy in various overexpressed gelatinase cancers.

The cytotoxic and growth inhibitory effects of palladium(II) complexes on MDA-MB-435 cells

The antitumorigenic potential of two palladium(II) complexes, [Pd(ca(2)-o-phen)Cl(2)] - C1 and [Pd(dmba)(dppp)Cl] - C2, was evaluated, using MDA-MB-435 cells, a human breast adenocarcinoma cell-line that does not express the estrogen receptor α (ER-). Growth inhibition and induced alterations in cell-morphology were analyzed. The sulforhodamine B test showed that, compared to control cells, both C1 and C2 significantly inhibited (p < 0.5) cell growth. The maximum effect with both was achieved with 1 μM complexes, after 24 h of treatment. No further cell-growth inhibition was achieved by increasing concentration or incubation time. Cell morphology was analyzed after staining with hematoxylin-eosin (HE). The morphological changes noted in the treated cells were cell rounding-up, shrinkage, nuclear condensation and reduction of cell length (p < 0.05), thereby indicating that both C1 and C2 are cytotoxic to breast adenocarcinoma cells. All together, there was every indication that, by decreasing cell growth and inducing morphological changes, the tested complexes are cytotoxic, hence their potentiality as promising candidates for antineoplastic drug development.