Influence of Canine Macrophage-derived Extracellular Vesicles on Apoptosis in Canine Melanoma and Osteosarcoma Cell Lines

BACKGROUND/AIM

The purpose of this study was to evaluate the effect of extracellular vesicles derived from canine M1-polarized macrophages (M1EVs) on canine tumor cells, such as D17 (osteosarcoma cells) and LMeC (melanoma cells).

MATERIALS AND METHODS

Protein expression was determined by western blot analysis. Gene expression was determined by RT-qPCR. In addition, cell apoptosis was analyzed by Annexin V/PI staining.

RESULTS

In the case of M1EV, the levels of pro-inflammatory cytokines such as TNF-α, IL-6 and IL-1β were increased, and nitrate/nitrite levels were also increased. M1EV induced apoptosis of tumor cells by increasing caspase-3 and caspase-7 activation. In addition, M1EVs decreased expression of CCR4, Foxp3 and CTLA-4 in canine peripheral mononuclear cells cocultured with tumor cells.

CONCLUSION

M1EV could be an effective anti-cancer therapeutic approach in melanoma and osteosarcoma and M1EVs can be used as immunomodulators in the tumor microenvironment for cancer treatment.

Poly(Ethylene Glycol)-b-Poly(D,L-Lactide) Nanoparticles as Potential Carriers for Anticancer Drug Oxaliplatin

Nanoparticles based on biocompatible methoxy poly(ethylene glycol)-b-poly(D,L-lactide) (mPEG₁₁₃-b-P(D,L)LA_n) copolymers as potential vehicles for the anticancer agent oxaliplatin were prepared by a nanoprecipitation technique. It was demonstrated that an increase in the hydrophobic PLA block length from 62 to 173 monomer units leads to an increase of the size of nanoparticles from 32 to 56 nm. Small-angle X-ray scattering studies confirmed the “core-corona” structure of mPEG₁₁₃-b-P(D,L)LA_n nanoparticles and oxaliplatin loading. It was suggested that hydrophilic oxaliplatin is adsorbed on the core-corona interface of the nanoparticles during the nanoprecipitation process. The oxaliplatin loading content decreased from 3.8 to 1.5% wt./wt. (with initial loading of 5% wt./wt.) with increasing PLA block length. Thus, the highest loading content of the anticancer drug oxaliplatin with its encapsulation efficiency of 76% in mPEG₁₁₃-b-P(D,L)LA_n nanoparticles can be achieved for block copolymer with short hydrophobic block.

Design, synthesis and pharmacological evaluation of novel Artemisinin-Thymol

A molecular hybridization of natural products is a new concept in drug discovery and having critical roles to design new molecules with improved biological properties. Hybrid molecules display higher biological activities when compared to the parent drugs. In the present study, two natural products (thymol and artemisinin (ART)) are used for the synthesis of new hybrid thymol-artemisinin. After characterization, the cytotoxic activity of ART-thymol was tested against different cancer cell lines and non-cancerous human cell line. ART-Thymol show the cytotoxic effect with EC₅₀ values 70,96μM for HepG2, 97,31μM for LnCap, 6,03μM for Caco-2, 77,98μM for HeLa and 62,28μM for HEK293 cells, respectively. Moreover, ART-Thymol was checked for drug-likeness, and the kinase inhibitory activity. ART-Thymol is investigated by using molecular docking. The results of qPCR was indicated CDK2 and P38 were inhibited by ART-Thymol. These results improved that thymol-artemisinin may be new candidates as an anticancer agents.

Zika M Oligopeptide ZAMP Confers Cell Death-Promoting Capability to a Soluble Tumor-Associated Antigen through Caspase-3/7 Activation

Mosquito-borne Zika virus (ZIKV) is an emerging flavivirus of medical concern associated with neurological disorders. ZIKV utilizes apoptosis as a mechanism of cell killing. The structural M protein may play a role in flavivirus-induced apoptosis. The death-promoting capability of M has been restricted to an oligopeptide representing the residues M-32/40. Here, we evaluated the apoptosis inducing ability of the residues M-31/41 of ZIKV. The ZIKV M oligopeptide was associated to a soluble form of GFP (sGFP) and the resulting sGFP-M31/41 construct was assessed in Huh7 cells. Expression of sGFP-M31/41 can trigger apoptosis in Huh7 cells through caspase-3/7 activation. The translocation of sGFP-M31/41 in the endoplasmic reticulum was a prerequisite for apoptosis induction. The residues M-33/35/38 may play a critical role in the death-promoting activity of sGFP-M31/41. The effect of ZIKV M oligopeptide defined as ZAMP (for Zika Apoptosis M Peptide) on expression of a tumor-associated antigen was assayed on megakaryocyte-potentiating factor (MPF). Expression of MPF-ZAMP construct resulted in caspase-associated apoptosis activation in A549 and Huh7 cells. ZIKV has been proposed as an oncolytic virus for cancer therapy. The ability of the Zika M oligopeptide to confer death-promoting capability to MPF opens up attractive perspectives for ZAMP as an innovative anticancer agent.

Cytotoxic compounds from the leaves and stems of the endemic Thai plant Mitrephora sirikitiae

Context: Mitrephora sirikitiae Weeras., Chalermglin & R.M.K. Saunders (Annonaceae) is a plant endemic to Thailand. Its constituents and their biological activities are unknown.Objective: Isolation and identification of the compounds in the leaves and stems of M. sirikitiae and determination of their cytotoxicity.Materials and methods: Methanol extracts of the leaves and stems of M. sirikitiae were separated by chromatography, and spectroscopic methods were used to determine the structures of the components. The cytotoxicity of the extracts and pure compounds was evaluated using the sulforhodamine B assay with several cell lines. The cells were treated with the compounds at concentrations of 0.16-20 µg/mL for 48 or 72 h.Results: The investigation of the extracts of M. sirikitiae leaves and stems resulted in the isolation of a new lignan, mitrephoran, and 15 known compounds. Among these compounds, 2-(3,4-dimethoxyphenyl)-6-(3,5-dimethoxyphenyl)-3,7-dioxabicyclo[3.3.0]octane, ciliaric acid, 6-methoxymarcanine A, and stepharanine were isolated from this genus for the first time. The alkaloids liriodenine and oxoputerine exhibited strong cytotoxicity against all tested cells (IC₅₀ values of 6.59-11.02 µM). In contrast, magnone A, 3',4-O-dimethylcedrusin, and 6-methoxymarcanine A inhibited the growth of some of the tested cells (IC₅₀ values of 2.03-19.73 µM). Magnone A and 6-methoxymarcanine A showed low toxicity for Hek 293 cells (IC₅₀ >20 µM).Discussion and conclusions: M. sirikitiae is a source of cytotoxic lignans and alkaloids. Among the cytotoxic compounds, magnone A and 6-methoxymarcanine A are potentially useful lead compounds for the further development of anticancer agents because of their selective inhibitory effects on cancer cell lines.

Benzothiazole derivatives as anticancer agents

Benzothiazole (BTA) belongs to the heterocyclic class of bicyclic compounds. BTA derivatives possesses broad spectrum biological activities such as anticancer, antioxidant, anti-inflammatory, anti-tumour, antiviral, antibacterial, anti-proliferative, anti-diabetic, anti-convulsant, analgesic, anti-tubercular, antimalarial, anti-leishmanial, anti-histaminic and anti-fungal among others. The BTA scaffolds showed a crucial role in the inhibition of the metalloenzyme carbonic anhydrase (CA). In this review an extensive literature survey over the last decade discloses the role of BTA derivatives mainly as anticancer agents. Such compounds are effective against various types of cancer cell lines through a multitude of mechanisms, some of which are poorly studied or understood. The inhibition of tumour associated CAs by BTA derivatives is on the other hand better investigated and such compounds may serve as anticancer leads for the development of agents effective against hypoxic tumours.

Toxicity and Anticancer Potential of Karwinskia: A Review

Karwinskia genus consists of shrubs and small trees. Four toxic compounds have been isolated from Karwinskia plants, which were typified as dimeric anthracenones and named T496, T514, T516, and T544. Moreover, several related compounds have been isolated and characterized. Here we review the toxicity of the fruit of Karwinskia plants when ingested (accidentally or experimentally), as well as the toxicity of its isolated compounds. Additionally, we analyze the probable antineoplastic effect of T514. Toxins cause damage mainly to nervous system, liver, lung, and kidney. The pathophysiological mechanism has not been fully understood but includes metabolic and structural alterations that can lead cells to apoptosis or necrosis. T514 has shown selective toxicity in vitro against human cancer cells. T514 causes selective and irreversible damage to peroxisomes; for this reason, it was renamed peroxisomicine A1 (PA1). Since a significant number of malignant cell types contain fewer peroxisomes than normal cells, tumor cells would be more easily destroyed by PA1 than healthy cells. Inhibition of topoisomerase II has also been suggested to play a role in the effect of PA1 on malignant cells. More research is needed, but the evidence obtained so far indicates that PA1 could be an effective anticancer agent.

Design, Synthesis, and In Vitro/In Vivo Anti-Cancer Activities of Novel (20S)-10,11-Methylenedioxy-Camptothecin Heterocyclic Derivatives

A novel camptothecin analogue, (20S)-10,11-methylenedioxy-camptothecin (FL118), has been proven to show significant antitumor efficacy for a wide variety of solid tumors. However, the further development of FL118 is severely hindered due to its extremely poor water solubility and adverse side effects. Here, two series of novel 20-substituted (20S)-10,11-methylenedioxy-camptothecin coupled with 5-substituted uracils and other heterocyclic rings through glycine were synthesized. All the derivatives showed superior cytotoxic activities in vitro with IC50 values in the nanomolar range. Among them, 12e displayed higher cytotoxic activities in several cancer cell lines with better water solubility than FL118. Our results further showed that, like FL118, 12e inhibited cell proliferation resulting from cell cycle arrest and apoptosis by blocking the anti-apoptotic gene transcription of survivin, Mcl-1, Bcl-2, and XIAP in both A549 cells and NCI-H446 cells. Furthermore, 12e did not show any inhibitory activity on Topo I, which is involved in hematopoietic toxicity. In vivo, 12e showed similar antitumor efficacy to FL118 but lower toxicity. Our findings indicate that 12e is a promising therapeutic agent for cancer treatment, and the core structure of FL118 represents a promising platform to generate novel FL118-based antitumor drugs.

Prospects and Therapeutic Applications of Cardiac Glycosides in Cancer Remediation

Active metabolites from natural sources are the predominant molecular targets in numerous biological studies owing to their appropriate compatibility with biological systems and desirable selective toxicities. Thus, their potential for therapeutic development could span a broad scope of disease areas, including pathological and neurological dysfunctions. Cardiac glycosides are a unique class of specialized metabolites that have been extensively applied as therapeutic agents for the treatment of numerous heart conditions, and more recently, they have also been explored as probable antitumor agents. They are a class of naturally derived compounds that bind to and inhibit Na⁺/K⁺-ATPase. This study presents cardiac glycosides and their analogues with highlights on their applications, challenges, and prospects as lead compounds for cancer treatment.

Apoptosis oxidative damage-mediated and antiproliferative effect of selenylated imidazo[1,2-a]pyridines on hepatocellular carcinoma HepG2 cells and in vivo

Imidazo[1,2-a]pyridines (IP) and organoselenium compounds have been widely exploited in medicinal chemistry due to their pharmacological activities. Hepatocellular carcinoma (HCC) has few treatment options, and unfortunately, the prognosis is poor. Thus, the development of novel therapeutic drugs is urgent. The present study aimed at evaluating the antitumor mechanism of selenylated IP against HepG2 cells and in vivo. The selenylated IP named IP-Se-06 (3-((2-methoxyphenyl)selanyl)-7-methyl-2-phenylimidazol[1,2-a]pyridine) showed high cytotoxicity against HepG2 cells (half-maximal inhibitory concentration [IC₅₀ ] = 0.03 µM) and selectivity for this tumor cell line. At nontoxic concentration, IP-Se-06 decreased the protein levels of Bcl-xL and increased the levels of p53, leading to inhibition of cell proliferation and apoptosis. This compound decreased the level of extracellular signal-regulated kinase 1/2 protein and changed the levels of proteins involved in the drive of the cell cycle, tumor growth, and survival (cyclin B1, cyclin-dependent kinase 2). In addition, IP-Se-06 decreased the number of cells in the S phase. In addition, IP-Se-06 led to increased generation of reactive oxygen species, changed antioxidant defenses, and caused DNA fragmentation. Finally, IP-Se-06 significantly inhibited the growth of Ehrlich ascites tumors in mice, increased survival time, and inhibited angiogenesis. Therefore, IP-Se-06 may be an important compound regarding the development of a therapeutic drug for HCC treatment.

Polish Propolis-Chemical Composition and Biological Effects in Tongue Cancer Cells and Macrophages

The purpose of this study was to compare the chemical composition and biological properties of Polish propolis. Ethanol, ethanol-hexane, hexane and hexane-ethanol extracts of propolis from three different regions of Poland were prepared. On the basis of the evaluation of their chemical composition as well as the extraction yield and free radical scavenging activity, the ethanol and hexane-ethanol extractions were proposed as the most effective methods. Subsequently, the biological properties of the extracts were evaluated to investigate the selectivity of an anticancer effect on tongue cancer cells in comparison to normal gingival fibroblasts. The obtained products demonstrated anticancer activity against tongue cancer cells. Additionally, when the lowest extract concentration (100 µg/mL) was applied, they were not cytotoxic to gingival fibroblasts. Finally, a possible anti-inflammatory potential of the prepared products was revealed, as reduced mitochondrial activity and proliferation of macrophages exposed to the extracts were observed. The results obtained indicate a potential of Polish propolis as a natural product with cancer-selective toxicity and anti-inflammatory effect. However, further studies are still needed to thoroughly explain the molecular mechanisms of its action and to obtain the promising health benefits of this versatile natural product.

Design, synthesis, and biological evaluation of 4-phenoxybenzenesulfonyl pyrrolidine derivatives as matrix metalloproteinase inhibitors

A series of 4-phenoxybenzenesulfonyl pyrrolidine derivatives were designed, synthesized, and evaluated as matrix metalloproteinases (MMPs) inhibitors. All of the synthesized compounds displayed inhibitory activity against MMP-2 and MMP-9. Compounds 4a, 4e, and 4i displayed more potent activity than the other compounds. While the three compounds mildly or moderately inhibited the proliferation of cancer cells, they significantly suppressed the migration and invasion of cancer cells at relatively low concentrations as determined by a wound healing assay and transwell assay. In addition, compound 4e suppressed vascular endothelial cell tube formation and sprouting of microvessels from aortic rings in vitro in a dose-dependent manner. Compound 4e markedly suppressed the pulmonary metastasis of H22 cells in mice. These findings along with molecular docking results suggested that compound 4e might be a promising candidate for further structural optimization to develop MMP inhibitors as potential anticancer agents.

[Drug Development Based on Intracellular Pharmacokinetic Analysis of Molecular Target Drug in Mice Bearing Patient-derived Xenograft Model]

Traditionally, anticancer drug discovery research has been conducted based on immortalized cancer cell lines, either cultured in vitro or grown in vivo. In the USA and Europe, patient derived xenograft (PDX) model is rapidly expelling traditional in vitro and in vivo models due to the good predictability of clinical outcome and its nature of retaining characteristics and heterogeneity in the original tumor. Furthermore, a significant association was also reported between drug responses in patient and corresponding PDX as high as 87%. We are preparing a PDX model for Japanese cancer patients including drug resistance examples and rare cancers. Using the established PDX model, we confirmed the possibility that the tumor microenvironment might affect the efficacy and distribution of drugs even if the target receptor is expressed in tumor sites as compared to the cell line (CDX) model, which has been widely used in drug discovery. Interestingly, although expressing a target receptor in viable tumor cells, we also have found a PDX model with a lower distribution of molecular target drug. Therefore we will evaluate the usefulness of the PDX model in drug development by exploring new biomarkers and elucidating the mechanisms of drug resistance in target tumors. Moreover, pharmaco-imaging system will allow us to visualize the exposure and distribution of drugs in tumors at macro and micro levels. Finally, we evaluate relations between distribution of drugs in the tumor microenvironment including target tumor cells, neovessels, stromal cells, immune cells, and fibroblasts.

Safety of Anticancer Agents Used in Children: A Focus on Their Off-Label Use Through Data From the Spontaneous Reporting System

BACKGROUND

Among factors influencing the higher risk of developing unknown or rare adverse drug reactions (ADRs) among children and adolescents, there is the frequent off-label use of drugs that seems to be very common in pediatric oncological patients. Our study aim to collect and evaluate data on the safety profile of antineoplastic drugs and their off-label use in the pediatrics population using real life data.

METHODS

We retrieved Individual Case Safety Reports (ICSRs) with an anticancer agent as suspected drug among those reported through the Campania spontaneous reporting system from 1 January 2013 to 30 September 2019. We classified ICSRs into four off-label categories: "age," "route of administration," "weight," and "therapeutic indication." We defined an ICSR as an off-label case if it met at least one of the aforementioned categories for at least one of the reported suspected antineoplastic drugs.

RESULTS

A total of 18 ICSRs (7.6%) out of 236 were classified as off-label cases. The median age of patients was 13 years (interquartile range, IQR: 6-16), with 94.4% of cases occurring in male patients. In the classification of the off-label category, 16 ICSRs were categorized according to the "therapeutic indication" and two for the "age." No case was categorized for the off-label categories "route of administration" and "weight." The two off-label cases categorized as "age" were both related to the use of brentuximab vedotin for Hodgkin's lymphoma in patients aged 16 years. Twenty-nine ADRs (1.6 suspected adverse drug reactions per ICSR) were identified among off-label cases. Among ADRs, those reported more than one were diarrhea (N = 3), neutropenia (N = 3), nausea (N = 2), pyrexia (N = 2), and vomit (N = 2).

CONCLUSIONS

Our findings showed a low number of ICSRs classified as off-label. The majority of off-label ICSRs were categorized for the "therapeutic indication." This low number of off-label ICSRs might be largely due to the underreporting phenomenon, which is a major limit in pharmacovigilance. Therefore, we believe that spreading pharmacovigilance knowledge and awareness might improve this aspect.

Enzymatic Synthesis of Ricinoleyl Hydroxamic Acid Based on Commercial Castor Oil, Cytotoxicity Properties and Application as a New Anticancer Agent

BACKGROUND

New anticancer agents that rely on natural/healthy, not synthetic/toxic, components are very much needed.

METHODS

Ricinoleyl hydroxamic acid (RHA) was synthesized from castor oil and hydroxylamine using Lipozyme TL IM as a catalyst. To optimize the conversion, the effects of the following parameters were investigated: type of organic solvent, period of reaction, amount of enzyme, the molar ratio of reactants and temperature. The highest conversion was obtained when the reaction was carried out under the following conditions: hexane as a solvent; reaction period of 48 hours; 120 mg of Lipozyme TL IM/3 mmol oil; HA-oil ratio of 19 mmol HA/3 mmol oil; and temperature of 40°C. The cytotoxicity of the synthesized RHA was assessed using human dermal fibroblasts (HDF), and its application towards fighting cancer was assessed using melanoma and glioblastoma cancer cells over a duration of 24 and 48 hours.

RESULTS

RHA was successfully synthesized  and it demonstrated strong anticancer activity against glioblastoma and melanoma cells at as low as a 1 µg/mL concentration while it did not demonstrate any toxicity against HDF cells.

CONCLUSION

This is the first report on the synthesis of RHA with great potential to be used as a new anticancer agent.

Hyaluronic Acid-Based Theranostic Nanomedicines for Targeted Cancer Therapy

Hyaluronic acid (HA) is a natural mucopolysaccharide and has many useful advantages, including biocompatibility, non-immunogenicity, chemical versatility, non-toxicity, biodegradability, and high hydrophilicity. Numerous tumor cells overexpress several receptors that have a high binding affinity for HA, while these receptors are poorly expressed in normal body cells. HA-based drug delivery carriers can offer improved solubility and stability of anticancer drugs in biological environments and allow for the targeting of cancer treatments. Based on these benefits, HA has been widely investigated as a promising material for developing the advanced clinical cancer therapies in various formulations, including nanoparticles, micelles, liposomes, and hydrogels, combined with other materials. We describe various approaches and findings showing the feasibility of improvement in theragnosis probes through the application of HA.

Secondary Metabolites from the Culture of the Marine-derived Fungus Paradendryphiella salina PC 362H and Evaluation of the Anticancer Activity of Its Metabolite Hyalodendrin

High-throughput screening assays have been designed to identify compounds capable of inhibiting phenotypes involved in cancer aggressiveness. However, most studies used commercially available chemical libraries. This prompted us to explore natural products isolated from marine-derived fungi as a new source of molecules. In this study, we established a chemical library from 99 strains corresponding to 45 molecular operational taxonomic units and evaluated their anticancer activity against the MCF7 epithelial cancer cell line and its invasive stem cell-like MCF7-Sh-WISP2 counterpart. We identified the marine fungal Paradendryphiella salina PC 362H strain, isolated from the brown alga Pelvetia caniculata (PC), as one of the most promising fungi which produce active compounds. Further chemical and biological characterizations of the culture of the Paradendryphiella salina PC 362H strain identified (-)-hyalodendrin as the active secondary metabolite responsible for the cytotoxic activity of the crude extract. The antitumor activity of (-)-hyalodendrin was not only limited to the MCF7 cell lines, but also prominent on cancer cells with invasive phenotypes including colorectal cancer cells resistant to chemotherapy. Further investigations showed that treatment of MCF7-Sh-WISP2 cells with (-)-hyalodendrin induced changes in the phosphorylation status of p53 and altered expression of HSP60, HSP70 and PRAS40 proteins. Altogether, our study reveals that this uninvestigated marine fungal crude extract possesses a strong therapeutic potential against tumor cells with aggressive phenotypes and confirms that members of the epidithiodioxopiperazines are interesting fungal toxins with anticancer activities.

Study of Cinobufagin as a Promising Anticancer Agent in Uveal Melanoma Through Intrinsic Apoptosis Pathway

Uveal melanoma (UM) is the most common primary intraocular carcinoma in adults. Cinobufagin, secreted by the Asiatic toad Bufo gargarizans, is a traditional Chinese medicine, widely used in tumor treatment. Here, we explored the potential antitumor function of cinobufagin and investigated its biochemical mechanisms in UM cells. The antitumor potential of cinobufagin was determined via cell viability, cell cycle, and apoptosis assays. Colony formation assays confirmed that cinobufagin exerted potent antitumor activity in a dose-dependent manner. We found that cinobufagin could induce cell apoptosis and upregulate the expression of cleaved caspase-3, cleaved poly(ADP-ribose) polymerase (PARP), and cleaved caspase-9 in vivo and in vitro. In addition, after treatment with increased concentrations of cinobufagin, the intrinsic mitochondrial apoptosis pathway was also activated, which was demonstrated by increased cell apoptosis with increased expression of Bad and Bax, decreased expression of Bcl-2 and Bcl-xl, and reduced mitochondrial membrane potential (MMP) in OCM1 cells. Taken together, the results of this preclinical study suggest that cinobufagin can both inhibit cell survival and induce cell apoptosis in a dose-dependent manner in UM cells, which provides new insights into the biochemical mechanism of cinobufagin and its potential as a future chemotherapeutic agent for UM.

Quantum dots encapsulated with curcumin inhibit the growth of colon cancer, breast cancer and bacterial cells

Aim: To synthesize and examine the impact of free Eudragit^® RS 100 nanoparticles (LN01), Quantum dots curcumin-loaded Eudragit RS 100 nanoparticles (LN04), and un-encapsulated curcumin nanoparticles (LN06) on cancerous and bacterial cells. Materials & methods: The LN01, LN04, LN06 were synthesized and characterized by Fourier transform infrared, ζ potential, UV-Vis spectroscopy, transmission electron microscopy and scanning electron microscopy and their biological activities were evaluated. Results: LN04 profoundly inhibited the growth of colon (HCT-116) cancerous cells (10.64% cell viability) and breast cancer (MCF-7) cells (10.32% cell viability) with compared to LN01 and LN06. Normal cells (HEK-293) did not show any inhibition after treatments. In addition, LN04 show better inhibitory action on bacterial growth compared with LN01 and LN06. Conclusion: We suggest that LN04 selectively target cancerous and bacterial cells and therefore possess potential anticancer and antibacterial capabilities.

Development of A Novel System Based on Green Magnetic / Graphene Oxide / Chitosan /Allium Sativum / Quercus / Nanocomposite for Targeted Release of Doxorubicin Anti-Cancer Drug

BACKGROUND

Doxorubicin, as a strong anti-cancer agent for clinical treatment of various cancer types along with other drugs, is widely utilized. Due to the physiology of the human body and cancerous tissues, the applicability of doxorubicin is still limited and the targeted treatment of the different types of cancers is considered. Also, the side effects of the conventional forms of chemotherapy medicines, damaging and stressing the normal cells are considerable.

OBJECTIVE

This study introduces a novel and effective system for the targeted release of doxorubicin by successfully fabricating the green magnetic graphene oxide, chitosan, allium sativum, and quercus nanocomposite.

METHODS

The in vitro release of doxorubicin loaded on the nanocomposite was evaluated and investigated at pH 7.4 and 6.5, respectively. The drug diffusivity in the plasma environment was assessed for a more accurate analysis of the drug diffusion process. The nanocomposite loaded drug release mechanism and kinetics, as well as cytotoxicity assay was investigated.

RESULTS

The efficiency of the drug encapsulation was significantly enhanced using natural extract ingredients and consequently, the efficacy of the targeted treatment of cancerous tissues was improved. The developed nanocomposite provided a controlled release of doxorubicin in similar acidic conditions of the normal and cancerous cells and affirming that the fabricated system is thoroughly pH-dependent.

CONCLUSION

The cytotoxicity assay confirmed that the fabricated nanocomposite at a high growth rate of cancerous cells has an anticancer property and acts as a toxic agent against tumor cells, suggesting that in conjunction with doxorubicin, it can be highly improved for killing cancerous cells.

Advances in histone demethylase KDM4 as cancer therapeutic targets

The KDM4 subfamily H3K9 histone demethylases are epigenetic regulators that control chromatin structure and gene expression by demethylating histone H3K9, H3K36, and H1.4K26. The KDM4 subfamily mainly consists of four proteins (KDM4A-D), all harboring the Jumonji C domain (JmjC) but with differential substrate specificities. KDM4A-C proteins also possess the double PHD and Tudor domains, whereas KDM4D lacks these domains. KDM4 proteins are overexpressed or deregulated in multiple cancers, cardiovascular diseases, and mental retardation and are thus potential therapeutic targets. Despite extensive efforts, however, there are very few KDM4-selective inhibitors. Defining the exact physiological and oncogenic functions of KDM4 demethylase will provide the foundation for the discovery of novel potent inhibitors. In this review, we focus on recent studies highlighting the oncogenic functions of KDM4s and the interplay between KDM4-mediated epigenetic and metabolic pathways in cancer. We also review currently available KDM4 inhibitors and discuss their potential as therapeutic agents for cancer treatment.

Peroxisomicine A1, a potential antineoplastic agent, causes micropexophagy in addition to macropexophagy

Peroxisomicine A1 (PA1) is a potential antineoplastic agent with high and selective toxicity toward peroxisomes of tumor cells. Pexophagy is a selective autophagy process that degrades damaged peroxisomes; this process has been studied mainly in methylotrophic yeasts. There are two main modes of pexophagy in yeast: macropexophagy and micropexophagy. Previous studies showed that peroxisomes damaged by a prolonged exposition to PA1 are eliminated by macropexophagy. In this work, Candida boidinii was grown in methanol-containing media, and PA1 was added to the cultures at 2 µg/mL after they reached the mid-exponential growth phase. Samples were taken at 5, 10, 15, 20, and 25 min after the addition of PA1 and processed for ultrastructural analysis. Typical morphological characteristics of micropexophagy were observed: the direct engulfment of peroxisomes by the vacuolar membrane and the presence of the micropexophagic membrane apparatus (MIPA), which mediates the fusion between the opposing tips of the vacuole to complete sequestration of peroxisomes from the cytosol. In conclusion, here we report that, in addition to macropexophagy, peroxisomes damaged by PA1 can be eliminated by micropexophagy. This information is useful to deepen the knowledge of the mechanism of action of PA1 and of that of pexophagy per se.

New Zampanolide Mimics: Design, Synthesis, and Antiproliferative Evaluation

Zampanolide is a promising microtubule-stabilizing agent (MSA) with a unique chemical structure. It is superior to the current clinically used MSAs due to the covalent nature of its binding to β-tubulin and high cytotoxic potency toward multidrug-resistant cancer cells. However, its further development as a viable drug candidate is hindered by its limited availability. More importantly, conversion of its chemically fragile side chain into a stabilized bioisostere is envisioned to enable zampanolide to possess more drug-like properties. As part of our ongoing project aiming to develop its mimics with a stable side chain using straightforward synthetic approaches, 2-fluorobenzyl alcohol was designed as a bioisosteric surrogate for the side chain based on its binding conformation as confirmed by the X-ray structure of tubulin complexed with zampanolide. Two new zampanolide mimics with the newly designed side chain have been successfully synthesized through a 25-step chemical transformation for each. Yamaguchi esterification and intramolecular Horner–Wadsworth–Emmons condensation were used as key reactions to construct the lactone core. The chiral centers at C17 and C18 were introduced by the Sharpless asymmetric dihydroxylation. Our WST-1 cell proliferation assay data in both docetaxel-resistant and docetaxel-naive prostate cancer cell lines revealed that compound 6 is the optimal mimic and the newly designed side chain can serve as a bioisostere for the chemically fragile N-acetyl hemiaminal side chain in zampanolide.

Different Effects of Cisplatin and Transplatin on the Higher-Order Structure of DNA and Gene Expression

Despite the effectiveness of cisplatin as an anticancer agent, its trans-isomer, transplatin, is clinically ineffective. Although both isomers target nuclear DNA, there is a large difference in the magnitude of their biological effects. Here, we compared their effects on gene expression in an in vitro luciferase assay and quantified their effects on the higher-order structure of DNA using fluorescence microscopy (FM) and atomic force microscopy (AFM). The inhibitory effect of cisplatin on gene expression was about 7 times that of transplatin. Analysis of the fluctuation autocorrelation function of the intrachain Brownian motion of individual DNA molecules showed that cisplatin increases the spring and damping constants of DNA by one order of magnitude and these visco-elastic characteristics tend to increase gradually over several hours. Transplatin had a weaker effect, which tended to decrease with time. These results agree with a stronger inhibitory effect of cisplatin on gene expression. We discussed the characteristic effects of the two compounds on the higher-order DNA structure and gene expression in terms of the differences in their binding to DNA.

Assessment of the antiproliferative and apoptotic roles of sulfonamide carbonic anhydrase IX inhibitors in HeLa cancer cell line

Carbonic anhydrase IX (CA IX) has recently been validated as an antitumor/antimetastatic drug target. In this study, we examined the underlying molecular mechanisms and the anticancer activity of sulfonamide CA IX inhibitors against cervical cancer cell lines. The effects of several sulfonamides on HeLa, MDA-MB-231, HT-29 cancer cell lines, and normal cell lines (HEK-293, PNT-1A) viability were determined. The compounds showed high cytotoxic and apoptotic activities, mainly against HeLa cells overexpressing CA IX. We were also examined for intracellular reactive oxygen species (ROS) production; intra-/extracellular pH changes, for inhibition of cell proliferation, cellular mitochondrial membrane potential change and for the detection of caspase 3, 8, 9, and CA IX protein levels. Of the investigated sulfonamides, one compound was found to possess high cytotoxic and anti-proliferative effects in HeLa cells. The cytotoxic effect occurred via apoptosis, being accompanied by a return of pHe/pHi towards normal values as for other CA IX inhibitors investigated earlier.

Thioalbamide, A Thioamidated Peptide from Amycolatopsis alba, Affects Tumor Growth and Stemness by Inducing Metabolic Dysfunction and Oxidative Stress

Thioalbamide, a thioamidated peptide biosynthesized by Amycolatopsis alba, is a thioviridamide-like molecule, and is part of a family of natural products representing a focus of biotechnological and pharmaceutical research in recent years due to their potent anti-proliferative and cytotoxic activities on malignant cells. Despite the high antitumor potential observed at nanomolar concentrations, the mechanisms underlying thioalbamide activity are still not known. In this work, the cellular effects induced by thioalbamide treatment on breast cancer cell lines were evaluated for the first time, highlighting the ability of this microbial natural peptide to induce mitochondrial dysfunction, oxidative stress, and apoptotic cell death. Furthermore, we demonstrate that thioalbamide can inhibit the propagation of cancer stem-like cells, which are strongly dependent on mitochondrial function and are responsible for chemotherapy resistance, metastasis, and tumor recurrence.

A novel 1,4-naphthoquinone-derived compound induces apoptotic cell death in breast cancer cells

Breast cancer is the most-diagnosed cancer type among women. The triple-negative subtype is an especially aggressive type of breast cancer. Although chemotherapy is almost the only option for the treatment of triple-negative breast cancer (TNBC), currently used chemotherapeutics are not effective enough, considering the poor survival rate of patients. Therefore, novel compounds need to be developed to improve survival rates. It has been known that quinonic compounds, which are found in nature, have antibacterial, antifungal, and antitumorigenic properties. Naphthoquinones are members of the quinone family and are widely used in research due to their promising properties. In this study, we evaluated the cytotoxic activity of a novel naphthoquinone-derived compound (1,4-naphthoquinone (1,4-NQ)) against two different breast cancer cells: a hormone-responsive cell line (MCF-7) and a triple-negative cell line (MDA-MB-231). As a result, 1,4-NQ decreased cell viability in both tested cell lines in a dose-dependent manner. Increased apoptotic markers (presence of pyknotic nuclei, annexin-V positivity, caspase 3/7 activity, and decreased mitochondrial membrane potential) and DNA damage were especially observed in MDA-MB-231 cells after treatment with the compound. Considering the promising cytotoxic effect of the compound, 1,4-NQ needs further evaluation as a potential candidate for the treatment of TNBC.

The role of therapeutic drug monitoring in the management of safety of anticancer agents: a focus on 3 cytotoxics

Introduction: Therapeutic drug monitoring in oncology is used to prevent major toxicities of selected anticancer agents due to overexposure by individualizing the dose based on a pharmacokinetic target. Areas covered: Numerous studies relating a relation between pharmacokinetic variability and toxicity have been reported since the eighties but very few have been implemented in clinical practice due to a lack of validation and harmonization, logistical constraints and reluctance from oncologists. Following recent recommendations, this paper highlights the current-validated applications of pharmacokinetic monitoring in oncology focusing on the safety of anticancer therapies. Expert opinion: Paradoxically given the oldness of the agents, guidelines of dose adjustment have been recently available for intravenous busulfan, 5-fluorouracil, and high-dose methotrexate. Interestingly, besides the enhancement of tolerability, it applies to potential curative clinical situations. In an era of personalized oncology that integrates complex molecular factors in the treatment of cancer, education is needed for oncologists to show the benefits of this valuable (even old) resource for the safety of patients. Therapeutic drug monitoring for busulfan, 5-fluorouracil and methotrexate will still hold in the future unless more active agents are available in the concerned indications.

Design and Synthesis of Anti-Cancer Chimera Molecules Based on Marine Natural Products

In this paper, the chemical conjugation of marine natural products with other bioactive molecules for developing an advanced anti-cancer agent is described. Structural complexity and the extraordinary biological features of marine natural products have led to tremendous research in isolation, structural elucidation, synthesis, and pharmacological evaluation. In addition, this basic scientific achievement has made it possible to hybridize two or more biologically important skeletons into a single compound. The hybridization strategy has been used to identify further opportunities to overcome certain limitations, such as structural complexity, scarcity problems, poor solubility, severe toxicity, and weak potency of marine natural products for advanced development in drug discovery. Further, well-designed marine chimera molecules can function as a platform for target discovery or degradation. In this review, the design, synthesis, and biological evaluation of recent marine chimera molecules are presented.

Targeted delivery of poly (methyl methacrylate) particles in colon cancer cells selectively attenuates cancer cell proliferation

Poly (methyl methacrylate) (PMMA) is basically biocompatible polyester with high resistance to chemical hydrolysis, and high drug permeability and the most important characteristics of PMMA is that it does not produce any toxicity. There is not much information about PMMA action on the colon cancer cells. In the present study, we have synthesized PMMA nanoparticles. The distribution pattern of PMMA particles was analysed by Zeta sizer and the size of the particles was calculated by using quasi elastic light scattering (QELS). The surface structure and the morphology of PMMA were characterized by transmission electron microscope (TEM) and scanning electron microscope (SEM), respectively. We have also analysed their effects on cancerous cells (human colorectal carcinoma cells, HCT-116) and normal, healthy cells (human embryonic kidney cells, HEK-293) by using morphometric, MTT, DAPI and wound healing methods. We report that PMMA particles inhibited the cancer cell viability in a dose-dependent manner. The lower dose (1.0 μg/ml) showed a moderate decrease in cancer cell viability, whereas higher dosages (2.5 μg/ml, 5.0 μg/mL and 7.5 μg/mL) showed steadily decrease in the cancer cell viability. We also report that PMMA is highly selective to cancerous cells (HCT-116), as we did not find any action on the normal healthy cells (HEK-293). In conclusion, our results suggest PMMA particles are potential biomaterials to be used in the treatment of colon cancer.

Intratumorally delivered formulation, INT230-6, containing potent anticancer agents induces protective T cell immunity and memory

The benefits of anti-cancer agents extend beyond direct tumor killing. One aspect of cell death is the potential to release antigens that initiate adaptive immune responses. Here, a diffusion enhanced formulation, INT230-6, containing potent anti-cancer cytotoxic agents, was administered intratumorally into large (approx. 300mm³) subcutaneous murine Colon26 tumors. Treatment resulted in regression from baseline in 100% of the tumors and complete response in up to 90%. CD8⁺ or CD8⁺/CD4⁺ T cell double-depletion at treatment onset prevented complete responses, indicating a critical role of T cells in promoting complete tumor regression. Mice with complete response were protected from subcutaneous and intravenous re-challenge of Colon26 cells in a CD4⁺/CD8⁺ dependent manner. Thus, immunological T cell memory was induced by INT230-6. Colon26 tumors express the endogenous retroviral protein gp70 containing the CD8⁺ T-cell AH-1 epitope. AH-1-specific CD8⁺ T cells were detected in peripheral blood of tumor-bearing mice and their frequency increased 14 days after treatment onset. AH-1-specific CD8⁺ T cells were also significantly enriched in tumors of untreated mice. These cells had an activated phenotype and highly expressed Programmed cell-death protein-1 (PD-1) but did not lead to tumor regression. CD8⁺ T cell tumor infiltrate also increased 11 days after treatment. INT230-6 synergized with checkpoint blockade, inducing a complete remission of the primary tumors and shrinking of untreated contralateral tumors, which demonstrates not only a local but also systemic immunological effect of the combined therapy. Similar T-cell dependent inhibition of tumor growth was also found in an orthotopic 4T1 breast cancer model.

In Silico Screening Reveals Histone Deacetylase 7 and ERK1/2 as Potential Targets for Artemisinin Dimer and Artemisinin Dimer Hemisuccinate

BACKGROUND

Recent studies have observed overexpression of histone deacetylase 7 (HDAC7) and overactivity of extracellular signal-regulated kinases 1/2 (ERK1/2) in many tumors; therefore, pharmacological interventions to inhibit overexpression of HDAC7 and overactivity of ERK1/2 in cancerous cells holds great promise in cancer treatment. The promising anticancer properties of artemisinin and artemisinin-derivatives (ARTs) have been validated by various experimental reports, including advanced pre-clinical trials.

OBJECTIVE

Our aim in this in silico study is to identify additional inhibitors of HDAC7, ERK1 and ERK2 as potential anticancer drug agents and provide insight into the molecular level of interactions of such ligands relative to known standards.

METHODS

To achieve this aim, the binding affinities of ulixertinib (the standard ERK inhibitor), apicidin (the standard HDAC7 inhibitor) as well as 49 ARTs for HDAC7, ERK1 and ERK2 were evaluated using AutodockVina. The molecular binding interactions of compounds with remarkable binding affinity for all the 3 target proteins, relative to their respective standards, were viewed with Discovery Studio Visualizer, BIOVIA, 2016.

RESULTS

Out of the 49 ARTs, our study identified 2 compounds, artemisinin dimer and artemisinin dimer hemisuccinate, as having higher binding affinities for all the target proteins compared to their respective standard inhibitors.

CONCLUSION

These findings suggest that artemisinin dimer and artemisinin dimer hemisuccinate could be promising anticancer drug agents, with better therapeutic efficacy than ulixertinib and apicidin for the treatment of cancer via inhibition of HDAC7, ERK1 and ERK2.

Conjugated Linolenic Acids: Implication in Cancer

Conjugated fatty acids (CFAs) including both conjugated linoleic acids (CLAs) and conjugated linolenic acids (CLNAs) have various health promoting effects. These beneficial effects are comprised by their antioxidant, antiatherogenecity, anticarcinogenic activities, etc. Several reports indicate that CLNAs such as eleostearic acid, punicic acid, jacaric acid, and calendic acid possess anticancer properties. These CLNAs are produced and accumulated in seeds of certain commonly available plants. This review discusses their role in chemoprevention of cancer. Using in vitro as well as in vivo models of cancer, bioactivities of these CLNAs have been explored in detail. CLNAs have been shown to have potent anticancer activity as compared to the CLAs. Although the molecular basis of these effects has been summarized here, more detailed studies are needed to explore the underlying mechanisms. Further clinical trials are obligatory for assessing the safety and efficacy of CLNAs as an anticancer agent.

Apoptotic effect of green synthesized gold nanoparticles from Curcuma wenyujin extract against human renal cell carcinoma A498 cells

Introduction: Curcuma wenyujin is a plant which belongs to the family of Zingiberaceae, found in South Asia and China. C. wenyujin is a major constituent in Chinese traditional medicine and is used to treat liver diseases, blood clots, and is also prescribed as a painkiller. C. wenyujin possesses antioxidant, antiproliferative, and antitumorogenic properties, and many researchers have proved the efficacy of C. wenyujin against various types of cancer. The major drawback of this historical drug is it's low bioavailability. Methods: This study synthesized gold nanoparticles using C. wenyujin and assessed its potency against in vitro renal cancer cells. The biosynthesized C. wenyujin gold nanoparticles (CWAuNPs) were characterized using UV-Spec, DLS, FTIR, SAED, TEM, EDAX, and Atomic Force analysis. The cytotoxicity of CWAuNPs against renal cancer cell lines A498 and SW-156 was assessed with MTT assay. The induction of apoptosis by CWAuNPs in A498 cell was measured using apoptotic staining DAPI, Rhodamine 123, and H2DCFDA. The apoptotic activity of CWAuNPs was further confirmed with flow cytometric analysis. The molecular mechanism of CWAuNPs was analyzed with qPCR and immunoblotting analysis of caspases, proapoptotic, and antiapoptotic proteins. Results: The characterization of results of synthesized CWAuNPs satisfy the distinctive properties of a potent nanodrug. The results of apoptotic staining techniques confirm the induction of CWAuNPs in A498 by increasing the apoptotic Caspase 3,9, Bid, and Bad, and decreasing the antiapoptotic protein Bcl-2, Bcl-xl expressions, which is authentically proven by the qPCR and immunoblotting analysis. Conclusion: In conclusion, these results confirmed that biosynthesized CWAuNPs is a potent anticancer agent which induces apoptosis in the A498 renal carcinoma cell line.

Synthesis and Biological Evaluation of 4β-N-Acetylamino Substituted Podophyllotoxin Derivatives as Novel Anticancer Agents

A series of novel podophyllotoxin derivatives obtained by 4β-N-acetylamino substitution at C-4 position was designed, synthesized, and evaluated for in vitro cytotoxicity against four human cancer cell lines (EC-9706, HeLA, T-24 and H460) and a normal human epidermal cell line (HaCaT). The cytotoxicity test indicated that most of the derivatives displayed potent anticancer activities. In particular, compound 12h showed high activity with IC₅₀ values ranging from 1.2 to 22.8 μM, with much better cytotoxic activity than the control drug etoposide (IC₅₀: 8.4 to 78.2 μM). Compound 12j exhibited a promising cytotoxicity and selectivity profile against T24 and HaCaT cell lines with IC₅₀ values of 2.7 and 49.1 μM, respectively. Compound 12g displayed potent cytotoxicity against HeLA and T24 cells with low activity against HaCaT cells. According to the results of fluorescence-activated cell sorting (FACS) analysis, 12g induced cell cycle arrest in the G2/M phase accompanied by apoptosis in T24 and HeLA cells. Furthermore, the docking studies showed possible interactions between human DNA topoisomerase IIα and 12g. These results suggest that 12g merits further optimization and development as a new podophyllotoxin-derived lead compound.

A review of the molecular design and biological activities of RXR agonists

An attractive approach to combat disease is to target theregulation of cell function. At the heart of this task are nuclear receptors (NRs); which control functions such as gene transcription. Arguably, the key player in this regulatory machinery is the retinoid X receptor (RXR). This NR associates with a third of the NRs found in humans. Scientists have hypothesized that controlling the activity of RXR is an attractive approach to control cellular functions that modulate diseases such as cancer, diabetes, Alzheimer's disease and Parkinson's disease. In this review, we will describe the key features of the RXR, present a historic perspective of the first RXR agonists, and discuss various templates that have been reported to activate RXR with a focus on their molecular structure, biological activity, and limitations. Finally, we will present an outlook of the field and future directions and considerations to synthesize or modulate RXR agonists to make these compounds a clinical reality.

The Potential Clinical Implications and Importance of Drug Interactions Between Anticancer Agents and Cannabidiol in Patients With Cancer

The objective of this review was to identify and examine the pharmacokinetic and pharmacodynamic interactions between cannabidiol (CBD)-only products, such as CBD oil, and anticancer agents. A literature search of PubMed (1980 to September 2018) and the Cochrane Collection (1980 to September 2018) was performed using the following search terms: "cannabidiol," "cancer," "cannabis," "marijuana," and "interaction," as well as any combination of these terms. Literature was excluded if it did not appear in the search when limited to the "full text" filter on PubMed, if it was not published in the English language, or if it did not explore potential pharmacodynamic or pharmacokinetic interactions of CBD and anticancer agents. There were 10 studies that met these inclusion criteria. The majority of the facts regarding the interactions with CBD were found using in vitro studies and the true in vivo implications are not well-known. Minimal data were available regarding the interactions between CBD and anticancer agents. However, pharmacists should always consider the possibility of interactions and their consequences whenever they are aware of a patient using CBD products.

The Iron Chelator and Anticancer Agent Dp44mT Relieves Allergic Inflammation in Mice With Allergic Rhinitis

Our previous study showed that an iron chelator and anticancer agent Di-2-pyridylketone-4,4-dimethyl-3-thiosemicarbazone (Dp44mT) has an antiinflammatory effect in human mast cells. However, antiinflammatory effect of Dp44mT remains unclear in animal models. In this study, we assessed whether administration of Dp44mT could relieve clinical symptoms of ovalbumin (OVA)-induced allergic rhinitis (AR) mice. After administration of Dp44mT, number of rubs was significantly decreased, and levels of histamine and IgE were suppressed in serum of AR mice. Also, serum levels of interleukin (IL)-1β, thymic stromal lymphopoietin (TSLP), and tumor necrosis factor (TNF)-α increased by OVA challenge were significantly lowered by administration of Dp44mT. T helper type 1 (Th1) cytokine interferon-γ level was significantly increased by administration of Dp44mT, whereas Th2 cytokines such as IL-4, IL-5, and IL-13 were significantly reduced by administration of Dp44mT. In intranasal tissues of AR mice, levels of IL-1β, TSLP, TNF-α, and IL-6 and activities and protein levels of caspase-1 were significantly reduced by administration of Dp44mT. Interestingly, administration of Dp44mT reduced number of infiltrated eosinophils and mast cells through the inhibition of macrophage inflammatory protein-2 and intercellular adhesion molecule-1 in intranasal tissues of AR mice. In conclusion, these results indicate that Dp44mT also has potential antiinflammatory effects in vivo as well as in vitro.

Oxaliplatin regulates myeloid-derived suppressor cell-mediated immunosuppression via downregulation of nuclear factor-κB signaling

Myeloid‐derived suppressor cells (MDSCs) represent one of the major types of immunoregulatory cells present under abnormal conditions, including cancer. These cells are characterized by their immature phenotype and suppressive effect on various immune effectors. In both human and mouse, there are two main subsets of MDSCs: polymorphonuclear (PMN)‐MDSCs and mononuclear (Mo)‐MDSCs. Thus, strategies to regulate MDSC‐mediated immunosuppression could result in the enhancement of anticancer immune responses. Oxaliplatin, a platinum‐based anticancer agent, is widely used in clinical settings. It is known to induce cell death by interfering with double‐stranded DNA and interrupting its replication and transcription. In this study, we found that oxaliplatin has the potential to regulate MDSC‐mediated immunosuppression in cancer. First, oxaliplatin selectively depleted MDSCs, especially Mo‐MDSCs, but only minimally affected T cells. In addition, sublethal doses of oxaliplatin eliminated the immunosuppressive capacity of MDSCs and induced the differentiation of MDSCs into mature cells. Oxaliplatin treatment diminished the expression of the immunosuppressive functional mediators arginase 1 (ARG1) and NADPH oxidase 2 (NOX2) in MDSCs, while an MDSC‐depleting agent, gemcitabine, did not downregulate these factors significantly. Oxaliplatin‐conditioned MDSCs had no tumor‐promoting activity in vivo. In addition, oxaliplatin modulated the intracellular NF‐κB signaling in MDSCs. Thus, oxaliplatin has the potential to be used as an immunoregulatory agent as well as a cytotoxic drug in cancer treatment.

Selective inhibition of carbonic anhydrase-IX by sulphonamide derivatives induces pH and reactive oxygen species-mediated apoptosis in cervical cancer HeLa cells

Selective inhibition with sulphonamides of carbonic anhydrase (CA) IX reduces cell proliferation and induces apoptosis in human cancer cells. The effect on CA IX expression of seven previously synthesised sulphonamide inhibitors, with high affinity for CA IX, as well as their effect on the proliferation/apoptosis of cancer/normal cell lines was investigated. Two normal and three human cancer cell lines were used. Treatment resulted in dose- and time-dependent inhibition of the growth of various cancer cell lines. One compound showed remarkably high toxicity towards CA IX-positive HeLa cells. The mechanisms of apoptosis induction were determined with Annexin-V and AO/EB staining, cleaved caspases (caspase-3, caspase-8, caspase-9) and cleaved PARP activation, reactive oxygen species production (ROS), mitochondrial membrane potential (MMP), intracellular pH (pHi), extracellular pH (pHe), lactate level and cell cycle analysis. The autophagy induction mechanisms were also investigated. The modulation of apoptotic and autophagic genes (Bax, Bcl-2, caspase-3, caspase-8, caspase-9, caspase-12, Beclin and LC3) was measured using real time PCR. The positive staining using γ-H2AX and AO/EB dye, showed increased cleaved caspase-3, caspase-8, caspase-9, increased ROS production, MMP and enhanced mRNA expression of apoptotic genes, suggesting that anticancer effects are also exerted through its apoptosis-inducing properties. Our results show that such sulphonamides might have the potential as new leads for detailed investigations against CA IX-positive cervical cancers.

Optimization of culture conditions and bench-scale production of anticancer enzyme L-asparaginase by submerged fermentation from Aspergillus terreus CCT 7693

L-Asparaginase amidohydrolase (EC 3.5.1.1) has received significant attention owing to its clinical use in acute lymphoblastic leukemia treatment and non-clinical applications in the food industry to reduce acrylamide (toxic compound) formation during the frying of starchy foods. In this study, a sequential optimization strategy was used to determine the best culture conditions for L-asparaginase production from filamentous fungus Aspergillus terreus CCT 7693 by submerged fermentation. The cultural conditions were studied using a 3-level, central composite design of response surface methodology, and biomass and enzyme production were optimized separately. The highest amount of biomass (22.0 g·L^-1) was obtained with modified Czapek-Dox medium containing glucose (14 g·L^-1), L-proline (10 g·L^-1), and ammonium nitrate (2 g·L^-1) fermented at 37.2 °C and pH 8.56; for maximum enzyme production (13.50 U·g^-1), the best condition was modified Czapek-Dox medium containing glucose (2 g·L^-1), L-proline (10 g·L^-1), and inoculum concentration of 4.8 × 10⁸ espore·mL^-1 adjusted to pH 9.49 at 34.6 °C. The L-asparaginase production profile was studied in a 7 L bench-scale bioreactor and a final specific activity of 13.81 U·g^-1 was achieved, which represents an increase of 200% in relation to the initial non-optimized conditions.

Selective cytotoxicity of green synthesized silver nanoparticles against the MCF-7 tumor cell line and their enhanced antioxidant and antimicrobial properties

Introduction

Silver nanoparticles (AgNPs) are of great interest due to their unique and controllable characteristics. Different synthesis methods have been proposed to produce these nanoparticles, which often require elevated temperatures/pressures or toxic solvents. Thus, green synthesis could be a replacement option as a simple, economically viable and environmentally friendly alternative approach for the synthesis of silver nanoparticles.

Methods

Here, the potential of the walnut green husk was investigated in the production of silver nanoparticles. An aqueous solution extracted from walnut green husk was used as a reducing agent as well as a stabilizing agent. Then, the synthesized nanoparticles were characterized with respect of their anticancer, antioxidant, and antimicrobial properties.

Results

Results showed that the synthesized nanoparticles possessed an average size of 31.4 nm with a Zeta potential of -33.8 mV, indicating high stability. A significant improvement in the cytotoxicity and antioxidant characteristics of the green synthesized Ag nanoparticles against a cancerous cell line was observed in comparison with the walnut green husk extract and a commercial silver nanoparticle (CSN). This could be due to a synergistic effect of the synthesized silver nanoparticles and their biological coating. AgNPs and the extract exhibited 70% and 40% cytotoxicity against MCF-7 cancerous cells, respectively, while CSN caused 56% cell death (at the concentration of 60 µg/mL). It was observed that AgNPs were much less cytotoxic when tested against a noncancerous cell line (L-929) in comparison with the control material (CSN). The free radical scavenging analysis demonstrated profound anti-oxidant activity for the synthesized nanoparticles in comparison with the extract and CSN. It was also detected that the synthesized AgNPs possess antibacterial activity against nosocomial and standard strains of both Gram-positive and Gram-negative bacteria (minimum inhibitory concentration =5-30 µg/mL).

Conclusion

These findings imply that the synthesized nanoparticles using green nanotechnology could be an ideal strategy to combat cancer and infectious diseases.

Targeting histones for degradation in cancer cells as a novel strategy in cancer treatment

The anticancer therapies with the joint treatment of a histone deacetylase (HDAC) inhibitor and a DNA-damaging approach are actively under clinical investigations, but the underlying mechanism is unclear. Histone homeostasis is critical to genome stability, transcriptional accuracy, DNA repair process, senescence, and survival. We have previously demonstrated that the HDAC inhibitor, trichostatin A (TSA), could promote the degradation of the core histones induced by γ-radiation or the DNAalkylating agent methyl methanesulfonate (MMS) in non-cancer cells, including mouse spermatocyte and embryonic fibroblast cell lines. In this study, we found that the joint treatment by TSA and MMS induced the death of the cultured cancer cells with an additive effect, but induced degradation of the core histones synergistically in these cells. We then analyzed various combinations of other HDAC inhibitors, including suberoylanilide hydroxamic acid and valproate sodium, with MMS or other DNAdamaging agents, including etoposide and camptothecin. Most of these combined treatments induced cell death additively, but all the tested combinations induced degradation of the core histones synergistically. Meanwhile, we showed that cell cycle arrest might not be a primary consequence for the joint treatment of TSA and MMS. Given that clinic treatments of cancers jointly with an HDAC inhibitor and a DNA-damaging approach often show synergistic effects, histone degradation might more accurately underlie the synergistic effects of these joint treatments in clinic applications than other parameters, such as cell death and cell cycle arrest. Thus, our studies might suggest that the degradation of the core histones can serve as a new target for the development of cancer therapies.

Synthesis and pharmacological evaluation of novel epidermal growth factor receptor inhibitors against prostate tumor cells

The aim of the present study was to investigate the activities of novel synthetic epidermal growth factor receptor (EGFR) inhibitors (ZINC05463076, ZINC2102846 and ZINC19901103) against prostate tumors, in vitro models and investigate the potential underlying mechanisms. A panel of prostate tumor cell lines (LNCaP, DU-145, PC-3 and LNCaP-AI cells) were used to evaluate antitumor activity of ZINC05463076, ZINC2102846, and ZINC19901103 in vitro. Cell growth and clonal formation were determined by MTT assay and Soft agar colony formation assay, respectively. An EGFR kinase assay following treatment of the compounds was performed by ELISA. Cell cycle-regulating proteins, including cyclin-dependent kinase (CDK)1, CKD2, CKD4 and inhibitory effects of these compounds on downstream signaling were analyzed by western blotting. Flow cytometry was performed to investigate apoptosis and cell cycle phases of the treated cells. It was revealed that all compounds synthesized in the present study demonstrated significant EGFR inhibition abilities, compared with approved EGFR inhibitor drug gefitinib. Treatment of LNCaP, DU-145, PC3 and LNCaP-AI cells with these compounds revealed cell proliferation inhibition and colony formation suppression dose-dependently in vitro. The agents impaired phosphorylation of EGFR and extracellular signal-regulated kinase 1/2 and suppressed their downstream signaling. In addition, these novel synthetic agents decreased the expression level of survivin, which may induce G₁ cell cycle phase arrest and cell apoptosis in PCa cells subsequently. Collectively, ZINC05463076, ZINC2102846 and ZINC19901103 exhibited significant antitumor activity in human prostate tumors in vitro, by inhibiting EGFR and promoting apoptosis, which suggested a rationale for clinical development in prostate tumor therapy.

Antitumor profile of the PI3K inhibitor ZSTK474 in human sarcoma cell lines

Treatment of patients with advanced sarcoma remains challenging due to lack of effective medicine, with the development of novel drugs being of keen interest. A pan-PI3K inhibitor, ZSTK474, has been evaluated in clinical trials against a range of advanced solid tumors, with clinical benefit shown in sarcoma patients. In the present study, we developed a panel of 14 human sarcoma cell lines and investigated the antitumor effect of 24 anticancer agents including ZSTK474, other PI3K inhibitors, and those clinically used for sarcoma treatment. ZSTK474 exhibited a similar antiproliferative profile to other PI3K inhibitors but was clearly different from the other drugs examined. Indeed, ZSTK474 inhibited PI3K-downstream pathways, in parallel to growth inhibition, in all cell lines examined, showing proof-of-concept of PI3K inhibition. In addition, ZSTK474 induced apoptosis selectively in Ewing's sarcoma (RD-ES and A673), alveolar rhabdomyosarcoma (SJCRH30) and synovial sarcoma (SYO-1, Aska-SS and Yamato-SS) cell lines, all of which harbor chromosomal translocation and resulting oncogenic fusion genes, EWSR1-FLI1, PAX3-FOXO1 and SS18-SSX, respectively. Finally, animal experiments confirmed the antitumor activity of ZSTK474 in vivo, with superior efficacy observed in translocation-positive cells. These results suggest that ZSTK474 could be a promising drug candidate for treating sarcomas, especially those harboring chromosomal translocation.

A Novel Class of Tyrosyl-DNA Phosphodiesterase 1 Inhibitors That Contains the Octahydro-2H-chromen-4-ol Scaffold

Tyrosyl-DNA phosphodiesterase 1 (Tdp1) is a DNA repair enzyme that mends topoisomerase 1-mediated DNA damage. Tdp1 is a current inhibition target for the development of improved anticancer treatments, as its inhibition may enhance the therapeutic effect of topoisomerase 1 poisons. Here, we report a study on the development of a novel class of Tdp1 inhibitors that is based on the octahydro-2H-chromene scaffold. Inhibition and binding assays revealed that these compounds are potent inhibitors of Tdp1, with IC50 and KD values in the low micromolar concentration range. Molecular modelling predicted plausible conformations of the active ligands, blocking access to the enzymatic machinery of Tdp1. Our results thus help establish a structural-activity relationship for octahydro-2H-chromene-based Tdp1 inhibitors, which will be useful for future Tdp1 inhibitor development work.

Novel Methylselenoesters Induce Programed Cell Death via Entosis in Pancreatic Cancer Cells

Redox active selenium (Se) compounds have gained substantial attention in the last decade as potential cancer therapeutic agents. Several Se compounds have shown high selectivity and sensitivity against malignant cells. The cytotoxic effects are exerted by their biologically active metabolites, with methylselenol (CH₃SeH) being one of the key executors. In search of novel CH₃SeH precursors, we previously synthesized a series of methylselenoesters that were active (GI₅₀ < 10 µM at 72 h) against a panel of cancer cell lines. Herein, we refined the mechanism of action of the two lead compounds with the additional synthesis of new analogs (ethyl, pentyl, and benzyl derivatives). A novel mechanism for the programmed cell death mechanism for Se-compounds was identified. Both methylseleninic acid and the novel CH₃SeH precursors induced entosis by cell detachment through downregulation of cell division control protein 42 homolog (CDC42) and its downstream effector β1-integrin (CD29). To our knowledge, this is the first time that Se compounds have been reported to induce this type of cell death and is of importance in the characterization of the anticancerogenic properties of these compounds.

Rationally Developed Metallogelators Derived from Pyridyl Derivatives of NSAIDs Displaying Anti-Inflammatory and Anticancer Activities

Metal-ligand coordination involving hydrogen-bond-functionalized ligands was employed rationally to get an easy access to a series of metallogelators derived from 3-pyridyl derivatives of nonsteroidal anti-inflammatory drugs [e.g., ibuprofen, sulindac, and flurbiprofen designated as 3-pyIBU, 3-pySUL, and 3-pyFLR, respectively] and biogenic metal centers [Zn(II), Cu(II), Mn(II), and Ag(I)]. A total of 13 metallogels (MG1-MG13) were obtained by allowing the ligands and the metal salts to react in dimethyl sulfoxide (DMSO)/water at room temperature. A slightly different solvent system (DMSO/water/MeOH) afforded four crystalline coordination complexes of 3-pyIBU, namely, [{Cu(3-pyIBU)₄(DMSO)₂}(NO₃)₂] (CC1), [{Ag(3-pyIBU)₂}(BF₄)] (CC2), [{Ag(3-pyIBU)₂}(ClO₄)] (CC3), and [{Cu(3-pyIBU)₄(CH₃OH)₂}(OTf)] (CC4), which were fully characterized by single-crystal X-ray diffraction. However, none of these coordination complexes produced metallogels-the results corroborated well with the rationale, based on which the metallogelators were obtained. Two selected metallogels (MG3 and MG9) could be leached out from the corresponding metallogels to the bulk solvent to the extent of 51 and 59%, respectively after 24 h of incubation at 37 °C, indicating their plausible use in topical application. Moreover, one of the selected metallogelators, i.e., MG9, displayed anti-inflammatory response and was able to inhibit the migration of highly aggressive human breast cancer cells MDA-MB-231, suggesting its plausible use as anticancer agent.

Cytotoxicity of Synthesized 1,4-Naphthoquinone Oxime Derivatives on Selected Human Cancer Cell Lines

In an effort to develop potent and selective antitumor agents, a series of 1,4-naphthoquinone oxime derivatives were designed and synthesized. The cytotoxicity of these compounds were evaluated against five human cancer cell lines (colorectal cancer cell: HCT-15, breast cancer cell: MDA-MB-231, liver cancer cell: BEL-7402, colorectal cancer cell: HCT-116 and ovarian cancer cell: A2780) in vitro. Among them, compound 14 was found to be the most potent cytotoxic compound against three cell lines (MDA-MB-231, BEL-7402 and A2780) with IC₅₀ values of 0.66±0.05, 5.11±0.12 and 8.26±0.22 µM, respectively. Additionally, the length of the side chains and the position of the substituent may also affect the cytotoxic activity of the naphthoquinone oxime derivatives. In general, compound 14 effectively inhibited breast cancer cell proliferation and may become a promising anticancer agent.

A452, an HDAC6-selective inhibitor, synergistically enhances the anticancer activity of chemotherapeutic agents in colorectal cancer cells

Although histone deacetylase inhibitors (HDACi) alone could be clinically useful, these are most recently used in combination with other anticancer agents in clinical trials for cancer treatment. Recently, we reported the anticancer activity of an HDAC6-selective inhibitor A452 toward various cancer cell types. This study aims to present a potent synergistic antiproliferative effect of A452/anticancer agent treatment in colorectal cancer cells (CRC) cells, independently of the p53 status. A452 in combination with irinotecan, or SAHA is more potent than either drug alone in the apoptotic pathway as evidenced by activated caspase-3 and PARP, increased Bak and pp38, decreased Bcl-xL, pERK, and pAKT, and induced apoptotic cells. Furthermore, A452 enhances DNA damage induced by anticancer agents as indicated by the increased accumulation of γH2AX and the activation of the checkpoint kinase Chk2. The silencing of HDAC6 enhances the cell growth inhibition and cell death caused by anticancer agents. In addition, A452 induces the synergistic suppression of cell migration and invasion. This study suggests a mechanism by which HDAC6-selective inhibition can enhance the efficacy of specific anticancer agents in CRC cells.