Topical Drug Delivery of Concentrated Cabazitaxel in an α-Tocopherol and DMSO Solution.

Topical chemotherapy approaches are relevant for certain skin cancer treatments. This study observes that cabazitaxel (CTX), a broad-spectrum second-generation taxane cytotoxic agent, can be dissolved in α-tocopherol at high concentrations exceeding 100 mg mL-1 . 2D nuclear magnetic resonance (NMR) analysis and molecular dynamics (MD) are used to study this phenomenon. The addition of 30% dimethyl sulfoxide (DMSO) to the α-tocopherol/CTX solution improves its working viscosity and enhances CTX permeation through human skin in vitro (over 5 µg cm-2 within 24 h), while no detectable drug permeates when CTX is dissolved in α-tocopherol alone. In a transepidermal water loss assay, the barrier impairment induced by CTX in 30% DMSO in α-tocopherol, but not in pure DMSO, is reversible 8 h after the formulation removal from the skin surface. Antitumor efficacy of the topical CTX formulation is evaluated in nude mice bearing A431 human squamous carcinoma skin cancer xenografts. With topical application of concentrated CTX solutions (75 mg mL-1 ), tumor growth is significantly suppressed compared to lower concentration groups (0, 25, or 50 mg mL-1 CTX). Taken together, these findings show that topical delivery of CTX using a DMSO and α-tocopherol solvent warrants further study as a treatment for skin malignancies.

The effect of long-term cigarette smoking on selected skin barrier proteins and lipids.

The negative impact of cigarette smoking on the skin includes accelerated aging, pigmentation disorders, and impaired wound healing, but its effect on the skin barrier is not completely understood. Here, we studied the changes in selected epidermal proteins and lipids between smokers (45-66 years, smoking > 10 years, > 10 cigarettes per day) and non-smokers. Volar forearm epidermal and stratum corneum samples, obtained by suction blister and tape stripping, respectively, showed increased thickness in smokers. In the epidermis of smokers, we observed a significant upregulation of filaggrin, loricrin, and a trend of increased involucrin but no differences were found in the case of transglutaminase 1 and kallikrein-related peptidase 7, on the gene and protein levels. No significant changes were observed in the major skin barrier lipids, except for increased cholesterol sulfate in smokers. Liquid chromatography coupled with mass spectrometry revealed shorter acyl chains in ceramides, and an increased proportion of sphingosine and 6-hydroxysphingosine ceramides (with C4 trans-double bond) over dihydrosphingosine and phytosphingosine ceramides in smokers, suggesting altered desaturase 1 activity. Smokers had more ordered lipid chains found by infrared spectroscopy. In conclusion, cigarette smoking perturbs the homeostasis of the barrier proteins and lipids even at a site not directly exposed to smoke.

Examination of diverse iron-chelating agents for the protection of differentiated PC12 cells against oxidative injury induced by 6-hydroxydopamine and dopamine.

Labile redox-active iron ions have been implicated in various neurodegenerative disorders, including the Parkinson's disease (PD). Iron chelation has been successfully used in clinical practice to manage iron overload in diseases such as thalassemia major; however, the use of conventional iron chelators in pathological states without systemic iron overload remains at the preclinical investigative level and is complicated by the risk of adverse outcomes due to systemic iron depletion. In this study, we examined three clinically-used chelators, namely, desferrioxamine, deferiprone and deferasirox and compared them with experimental agent salicylaldehyde isonicotinoyl hydrazone (SIH) and its boronate-masked prochelator BSIH for protection of differentiated PC12 cells against the toxicity of catecholamines 6-hydroxydopamine and dopamine and their oxidation products. All the assayed chelating agents were able to significantly reduce the catecholamine toxicity in a dose-dependent manner. Whereas hydrophilic chelator desferrioxamine exerted protection only at high and clinically unachievable concentrations, deferiprone and deferasirox significantly reduced the catecholamine neurotoxicity at concentrations that are within their plasma levels following standard dosage. SIH was the most effective iron chelator to protect the cells with the lowest own toxicity of all the assayed conventional chelators. This favorable feature was even more pronounced in prochelator BSIH that does not chelate iron unless its protective group is cleaved in disease-specific oxidative stress conditions. Hence, this study demonstrated that while iron chelation may have general neuroprotective potential against catecholamine auto-oxidation and toxicity, SIH and BSIH represent promising lead molecules and warrant further studies in more complex animal models.

Phospholipid-Based Microemulsions for Cutaneous Imiquimod Delivery.

Imiquimod (IMQ) is a potent immune response modifier with antiviral and antitumor properties. IMQ's low aqueous solubility and unsatisfactory cutaneous permeability limit its formulation into effective dosage forms. This work aimed to develop IMQ-loaded microemulsions (MEs) based on phospholipids and oleic acid to improve IMQ penetration into the epidermis. A pseudo-ternary phase diagram was constructed, and the microstructure of the formulations was examined by measuring the conductivity values. Selected MEs were characterized and studied for their ability to deliver IMQ into and through ex vivo human skin. ME1 with 1% IMQ (bicontinuous ME with Bingham rheology) delivered similar IMQ quantities to the human epidermis ex vivo as the commercial product while having a 5-fold lower IMQ dose. IMQ was not detected in the acceptor phase after the permeation experiment, suggesting a lower systemic absorption risk than the established product. Infrared spectroscopy of the stratum corneum revealed less ordered and less tightly packed lipids after ME1 application. The ME1-induced barrier disruption recovered within less than 5 h after the formulation removal, as detected by transepidermal water loss measurements. In conclusion, our findings demonstrate that phospholipid and oleic acid-based MEs could become a promising alternative for topical IMQ administration.

Common Cosmetic Compounds Can Reduce Air Pollution-Induced Oxidative Stress and Pro-Inflammatory Response in the Skin.

INTRODUCTION: Constantly increasing air pollution (AP) poses a concern affecting not only our health but also our skin. A typical manifestation of the skin damage induced by AP is its premature aging, irritation, skin barrier impairment, pigmentation disorders, and development or exacerbation of various skin diseases. For these reasons, it is crucial to protect the skin from the negative effects of AP. In this study, we evaluated the ability of some compounds commonly used in dermatological or cosmetic preparations with various biological activities to reduce AP-induced skin damage. METHODS: We established a new experimental model using porcine skin explants exposed to cigarette smoke (CS) in which we determined the level of reactive oxygen species (ROS) in the stratum corneum, skin barrier lipids peroxidation, and gene expression of the pro-inflammatory cytokine interleukin 6 in the epidermis. Then, we tested several polysaccharides and their derivatives such as sodium hyaluronate (SH) of different molecular weight (MW, 1.6 MDa, 300 kDa, 15 kDa, 5 kDa), yeast glucomannan, schizophyllan, and carboxymethyl ß-glucan, then vitamin C derivative sodium ascorbyl phosphate, niacinamide, and D-panthenol for their ability to prevent CS-induced skin damage. For the evaluation and comparison of their mechanism of action, film-forming effect was determined by TEWL and gloss measurements and the antioxidant properties were assessed by DPPH assay. RESULTS: In the skin samples exposed to CS, we observed significant negative changes such as the presence of large amount of ROS in the stratum corneum, high level of skin barrier lipids peroxidation and upregulated IL6 gene expression. Pretreatment of the skin samples with all the tested substances significantly prevented CS-induced skin damage. The most effective were high MW SH probably due to its best film-forming effect and sodium ascorbyl phosphate with the best antioxidant properties. CONCLUSION: AP leads to a significant skin damage which can be effectively prevented using some conventional cosmetic and dermatological ingredients with various mechanisms of action.

Esters of terpene alcohols as highly potent, reversible, and low toxic skin penetration enhancers.

Skin penetration/permeation enhancers are compounds that improve (trans)dermal drug delivery. We designed hybrid terpene-amino acid enhancers by conjugating natural terpenes (citronellol, geraniol, nerol, farnesol, linalool, perillyl alcohol, menthol, borneol, carveol) or cinnamyl alcohol with 6-(dimethylamino)hexanoic acid through a biodegradable ester linker. The compounds were screened for their ability to increase the delivery of theophylline and hydrocortisone through and into human skin ex vivo. The citronellyl, bornyl and cinnamyl esters showed exceptional permeation-enhancing properties (enhancement ratios up to 82) while having low cellular toxicities. The barrier function of enhancer-treated skin (assessed by transepidermal water loss and electrical impedance) recovered within 24 h. Infrared spectroscopy suggested that these esters fluidized the stratum corneum lipids. Furthermore, the citronellyl ester increased the epidermal concentration of topically applied cidofovir, which is a potent antiviral and anticancer drug, by 15-fold. In conclusion, citronellyl 6-(dimethylamino)hexanoate is an outstanding enhancer with an advantageous combination of properties, which may improve the delivery of drugs that have a limited ability to cross biological barriers.

HILIC/ESI-MS determination of gangliosides and other polar lipid classes in renal cell carcinoma and surrounding normal tissues.

Negative-ion hydrophilic liquid chromatography-electrospray ionization mass spectrometry (HILIC/ESI-MS) method has been optimized for the quantitative analysis of ganglioside (GM3) and other polar lipid classes, such as sulfohexosylceramides (SulfoHexCer), sulfodihexosylceramides (SulfoHex2Cer), phosphatidylglycerols (PG), phosphatidylinositols (PI), lysophosphatidylinositols (LPI), and phosphatidylserines (PS). The method is fully validated for the quantitation of the studied lipids in kidney normal and tumor tissues of renal cell carcinoma (RCC) patients based on the lipid class separation and the coelution of lipid class internal standard with the species from the same lipid class. The raw data are semi-automatically processed using our software LipidQuant and statistically evaluated using multivariate data analysis (MDA) methods, which allows the complete differentiation of both groups with 100% specificity and sensitivity. In total, 21 GM3, 28 SulfoHexCer, 26 SulfoHex2Cer, 10 PG, 19 PI, 4 LPI, and 7 PS are determined in the aqueous phase of lipidomic extracts from kidney tumor tissue samples and surrounding normal tissue samples of 20 RCC patients. S-plots allow the identification of most upregulated (PI 40:5, PI 40:4, GM3 34:1, and GM3 42:2) and most downregulated (PI 32:0, PI 34:0, PS 36:4, and LPI 16:0) lipids, which are primarily responsible for the differentiation of tumor and normal groups. Another confirmation of most dysregulated lipids is performed by the calculation of fold changes together with T and p values to highlight their statistical significance. The comparison of HILIC/ESI-MS data and matrix-assisted laser desorption/ionization mass spectrometric imaging (MALDI-MSI) data confirms that lipid dysregulation patterns are similar for both methods. Graphical abstract ᅟ.

Structure-Activity Relationships of Nitro-Substituted Aroylhydrazone Iron Chelators with Antioxidant and Antiproliferative Activities.

Aroylhydrazone iron chelators such as salicylaldehyde isonicotinoyl hydrazone (SIH) protect various cells against oxidative injury and display antineoplastic activities. Previous studies have shown that a nitro-substituted hydrazone, namely, NHAPI, displayed markedly improved plasma stability, selective antitumor activity, and moderate antioxidant properties. In this study, we prepared four series of novel NHAPI derivatives and explored their iron chelation activities, anti- or pro-oxidant effects, protection against model oxidative injury in the H9c2 cell line derived from rat embryonic cardiac myoblasts, cytotoxicities to the corresponding noncancerous H9c2 cells, and antiproliferative activities against the MCF-7 human breast adenocarcinoma and HL-60 human promyelocytic leukemia cell lines. Nitro substitution had both negative and positive effects on the examined properties, and we identified new structure-activity relationships. Naphthyl and biphenyl derivatives showed selective antiproliferative action, particularly in the breast adenocarcinoma MCF-7 cell line, where they exceeded the selectivity of the parent compound NHAPI. Of particular interest is a compound prepared from 2-hydroxy-5-methyl-3-nitroacetophenone and biphenyl-4-carbohydrazide, which protected cardiomyoblasts against oxidative injury at 1.8 ± 1.2 µM with 24-fold higher selectivity than SIH. These compounds will serve as leads for further structural optimization and mechanistic studies.

Phase I/II trial of dendritic cell-based active cellular immunotherapy with DCVAC/PCa in patients with rising PSA after primary prostatectomy or salvage radiotherapy for the treatment of prostate cancer.

OBJECTIVE: Immunotherapy of cancer has the potential to be effective mostly in patients with a low tumour burden. Rising PSA (prostate-specific antigen) levels in patients with prostate cancer represents such a situation. We performed the present clinical study with dendritic cell (DC)-based immunotherapy in this patient population. MATERIALS AND METHODS: The single-arm phase I/II trial registered as EudraCT 2009-017259-91 involved 27 patients with rising PSA levels. The study medication consisted of autologous DCs pulsed with the killed LNCaP cell line (DCVAC/PCa). Twelve patients with a favourable PSA response continued with the second cycle of immunotherapy. The primary and secondary objectives of the study were to assess the safety and determine the PSA doubling time (PSADT), respectively. RESULTS: No significant side effects were recorded. The median PSADT in all treated patients increased from 5.67 months prior to immunotherapy to 18.85 months after 12 doses (p < 0.0018). Twelve patients who continued immunotherapy with the second cycle had a median PSADT of 58 months that remained stable after the second cycle. In the peripheral blood, specific PSA-reacting T lymphocytes were increased significantly already after the fourth dose, and a stable frequency was detected throughout the remainder of DCVAC/PCa treatment. Long-term immunotherapy of prostate cancer patients experiencing early signs of PSA recurrence using DCVAC/PCa was safe, induced an immune response and led to the significant prolongation of PSADT. Long-term follow-up may show whether the changes in PSADT might improve the clinical outcome in patients with biochemical recurrence of the prostate cancer.

Comparison of suction blistering and tape stripping for analysis of epidermal genes, proteins and lipids.

Analysis of epidermal genes, proteins and lipids is important in the research and diagnosis of skin diseases. Although punch biopsy is the first-choice technique for the skin sampling, it is unnecessarily invasive for obtaining a sample just for the epidermal analysis. Here we compare two less invasive methods, suction blistering (SB) and tape stripping (TS), for the analysis of selected epidermal genes (quantitative real-time reverse transcription PCR, qRT-PCR), proteins (western blotting, WB), and lipids in ten healthy volunteers. TS provided significantly less material than SB and no viable epidermal layers could be obtained according to the reflectance confocal microscopy. Consistently, only the SC protein filaggrin and housekeeping GAPDH together with FLG and RPL13A mRNA were detected by TS. In the SB samples, WB and qRT-PCR could easily detect all the selected proteins (claudin-1, occludin, filaggrin, laminin and GAPDH) and genes (CLDN1, OCLN, FLG, LAMA3 and RPL13A), respectively. A single SB sample further provided enough of material for immunohistochemistry and lipid analyses, which was not feasible with the TS samples. Immunohistochemistry of the SB samples showed intact epidermal structure and a characteristic expression of claudin-1. Infrared spectroscopy showed well-ordered lipids with both orthorhombic and hexagonal packing and high-performance thin layer chromatography confirmed all lipid classes (including ceramide subclasses) in correct proportions. Taken together, SB represents a reliable sampling technique that can be utilized for multipurpose epidermal analyses in various studies.

Personalized ex vivo multiple peptide enrichment and detection of T cells reactive to multiple tumor-associated antigens in prostate cancer patients.

Personalized peptide vaccination is a promising immunotherapeutic approach in prostate cancer (PCa). We therefore examined whether an approach, utilizing personalized multiple peptide-mediated ex vivo enrichment with effector T cells reactive to multiple tumor-associated antigens (TAAs), could be employed as a basis for the development of T cell immunotherapy of PCa. In this study, we used the non-adherent fraction (lymphocytes) of cryopreserved peripheral blood mononuclear cells from a leukapheretic product of biochemically recurrent (BR, n = 14) and metastatic hormone-refractory (HR, n = 12) PCa patients. The lymphocytes were primed with a pool of mixed overlapping peptides derived from 6 PCa TAAs-PSA, PAP, NY-ESO-1, MAGE-A1, MAGE-A3 and MAGE-A4. After 2 weeks of culture, the cells were stimulated with the peptides and T cell reactivity determined by externalization of CD107a. No TAAs-reactive effector T cells were detected in the patient's lymphocytes after their reconstitution. However, following their priming with the TAAs-derived peptides and 2-week culturing, the lymphocytes became enriched with polyclonal TAAs-reactive effector CD8+ T cells in 8 out of 14 BR and 5 out of 12 HR patients. No such reactive CD8+ T cells were detected in cultured lymphocytes without the peptide priming. Stimulation of the responding cultures with peptides derived from individual TAAs revealed a unique repertoire of the reactive CD8+ T cells. Our strategy revealed that the personalized multiple peptide-mediated ex vivo enrichment with multiple TAAs-reactive T cells in the PCa patient's lymphocytes is a viable approach for development of T cell immunotherapy of PCa.

Development of water-soluble 3,5-dinitrophenyl tetrazole and oxadiazole antitubercular agents.

In this work, four series of tertiary amine-containing derivatives of 3,5-dinitrophenyl tetrazole and oxadiazole antitubercular agents were prepared, and their in vitro antimycobacterial effects were evaluated. We found that the studied compounds showed lipophilicity-dependent antimycobacterial activity. The N-benzylpiperazine derivatives, which had the highest lipophilicity among all of the series, showed the highest in vitro antimycobacterial activities against Mycobacterium tuberculosis CNCTC My 331/88 (H37Rv), comparable to those of the first-line drugs isoniazid and rifampicin. The presence of two tertiary amines in these N-benzylpiperazine derivatives enabled us to prepare water-soluble dihydrochloride salts, overcoming the serious drawback of previously described 3,5-dinitrophenyl tetrazole and oxadiazole lead compounds. The water-soluble 3,5-dinitrophenyl tetrazole and oxadiazole antitubercular agents described in this work are good candidates for further in vitro and in vivo pharmacokinetic and pharmacodynamic studies.

S-substituted 3,5-dinitrophenyl 1,3,4-oxadiazole-2-thiols and tetrazole-5-thiols as highly efficient antitubercular agents.

Two new classes of antitubercular agents, namely 5-alkylsulfanyl-1-(3,5-dinitrophenyl)-1H-tetrazoles and 2-alkylsulfanyl-5-(3,5-dinitrophenyl)-1,3,4-oxadiazoles, and their structure-activity relationships are described. These compounds possessed excellent activity against Mycobacterium tuberculosis, including the clinically isolated multidrug (MDR) and extensively drug-resistant (XDR) strains, with no cross resistance with first or second-line anti-TB drugs. The minimum inhibitory concentration (MIC) values of the most promising compounds reached 0.03 µM. Furthermore, these compounds had a highly selective antimycobacterial effect because they were completely inactive against 4 gram positive and 4 gram negative bacteria and eight fungal strains and had low in vitro toxicity for four mammalian cell lines, including hepatic cell lines HepG2 and HuH7. Although the structure-activity relationship study showed that the presence of two nitro groups is highly beneficial for antimycobacterial activity, the analogues with a trifluoromethyl group instead of one of the nitro groups maintained a high antimycobacterial activity, which indicates the possibility for further structural optimization of this class of antitubercular agents.

Generation of T cell effectors using tumor cell-loaded dendritic cells for adoptive T cell therapy.

Adoptive T cell transfer has been shown to be an effective method used to boost tumor-specific immune responses in several types of malignancies. In this study, we set out to optimize the ACT protocol for the experimental treatment of prostate cancer. The protocol includes a pre-stimulation step whereby T cells were primed with autologous dendritic cells loaded with the high hydrostatic pressure-treated prostate cancer cell line, LNCaP. Primed T cells were further expanded in vitro with anti-CD3/CD28 Dynabeads in the WAVE bioreactor 2/10 system and tested for cytotoxicity. Our data indicates that the combination of pre-stimulation and expansion steps resulted in the induction and enrichment of tumor-responsive CD4+ and CD8+ T cells at clinically relevant numbers. The majority of both CD4+ and CD8+ IFN-γ producing cells were CD62L, CCR7 and CD57 negative but CD28 and CD27 positive, indicating an early antigen experienced phenotype in non-terminal differentiation phase. Expanded T cells showed significantly greater cytotoxicity against LNCaP cells compared to the control SKOV-3, an ovarian cancer line. In summary, our results suggest that the ACT approach together with LNCaP-loaded dendritic cells provides a viable way to generate prostate cancer reactive T cell effectors that are capable of mounting efficient and targeted antitumor responses and can be thus considered for further testing in a clinical setting.

Aroylhydrazone iron chelators: Tuning antioxidant and antiproliferative properties by hydrazide modifications.

Aroylhydrazones such as salicylaldehyde isonicotinoyl hydrazone (SIH) are tridentate iron chelators that may possess antioxidant and/or antineoplastic activities. Their main drawback, their low stability in plasma, has recently been partially overcome by exchanging the aldimine hydrogen for an unbranched alkyl group. In this study, ten analogs of methyl- and ethyl-substituted SIH derivatives with modified hydrazide scaffolds were synthesized to further explore their structure-activity relationships. Their iron-chelation efficiencies, anti- or pro-oxidant potentials, abilities to induce protection against model oxidative injury on the H9c2 cell line derived from rat embryonic cardiac tissue, cytotoxicities on the same H9c2 cells and antiproliferative activities on MCF-7 human breast adenocarcinoma and HL-60 human promyelotic leukemia cell lines were evaluated. Compounds derived from lipophilic naphthyl and biphenyl hydrazides displayed highly selective antiproliferative activities against both MCF-7 and HL-60 cell lines, and they showed markedly improved stabilities in plasma compared to SIH. Of particular interest is a hydrazone prepared from 2-hydroxypropiophenone and pyridazin-4-carbohydrazide that showed a considerable antiproliferative effect and protected cardiomyoblasts against oxidative stress with a five-fold higher selectivity compared to the parent compound SIH. Thus, this work highlighted new structure-activity relationships among antiproliferative and antioxidant aroylhydrazones and identified new lead compounds for further development.

The barrier function of organotypic non-melanoma skin cancer models.

Non-melanoma skin cancer (NMSC) is the most frequent human cancer with continuously rising incidences worldwide. Herein, we investigated the molecular basis for the impaired skin barrier function of organotypic NMSC models. We unraveled disturbed epidermal differentiation by reflectance confocal microscopy and histopathological evaluation. While the presence of claudin-4 and occludin were distinctly reduced, zonula occludens protein-1 was more wide-spread, and claudin-1 was heterogeneously distributed within the NMSC models compared with normal reconstructed human skin. Moreover, the cancer altered stratum corneum lipid packing and profile with decreased cholesterol content, increased phospholipid amount, and altered ceramide subclasses. These alterations contributed to increased surface pH and to 1.5 to 2.6-fold enhanced caffeine permeability of the NMSC models. Three topical applications of ingenol mebutate gel (0.015%) caused abundant epidermal cell necrosis, decreased Ki-67 indices, and increased lactate dehydrogenase activity. Taken together, our study provides new biological insights into the microenvironment of organotypic NMSC models, improves the understanding of the disease model by revealing causes for impaired skin barrier function in NMSC models at the molecular level, and fosters human cell-based approaches in preclinical drug evaluation.

In Vitro Characterization of the Pharmacological Properties of the Anti-Cancer Chelator, Bp4eT, and Its Phase I Metabolites.

Cancer cells have a high iron requirement and many experimental studies, as well as clinical trials, have demonstrated that iron chelators are potential anti-cancer agents. The ligand, 2-benzoylpyridine 4-ethyl-3-thiosemicarbazone (Bp4eT), demonstrates both potent anti-neoplastic and anti-retroviral properties. In this study, Bp4eT and its recently identified amidrazone and semicarbazone metabolites were examined and compared with respect to their anti-proliferative activity towards cancer cells (HL-60 human promyelocytic leukemia, MCF-7 human breast adenocarcinoma, HCT116 human colon carcinoma and A549 human lung adenocarcinoma), non-cancerous cells (H9c2 neonatal rat-derived cardiomyoblasts and 3T3 mouse embryo fibroblasts) and their interaction with intracellular iron pools. Bp4eT was demonstrated to be a highly potent and selective anti-neoplastic agent that induces S phase cell cycle arrest, mitochondrial depolarization and apoptosis in MCF-7 cells. Both semicarbazone and amidrazone metabolites showed at least a 300-fold decrease in cytotoxic activity than Bp4eT towards both cancer and normal cell lines. The metabolites also lost the ability to: (1) promote the redox cycling of iron; (2) bind and mobilize iron from labile intracellular pools; and (3) prevent 59Fe uptake from 59Fe-labeled transferrin by MCF-7 cells. Hence, this study demonstrates that the highly active ligand, Bp4eT, is metabolized to non-toxic and pharmacologically inactive analogs, which most likely contribute to its favorable pharmacological profile. These findings are important for the further development of this drug candidate and contribute to the understanding of the structure-activity relationships of these agents.

Phase I/II clinical trial of dendritic-cell based immunotherapy (DCVAC/PCa) combined with chemotherapy in patients with metastatic, castration-resistant prostate cancer.

PURPOSE: We conducted an open-label, single-arm Phase I/II clinical trial in metastatic CRPC (mCRPC) patients eligible for docetaxel combined with treatment with autologous mature dendritic cells (DCs) pulsed with killed LNCaP prostate cancer cells (DCVAC/PCa). The primary and secondary endpoints were safety and immune responses, respectively. Overall survival (OS), followed as a part of the safety evaluation, was compared to the predicted OS according to the Halabi and MSKCC nomograms. EXPERIMENTAL DESIGN: Twenty-five patients with progressive mCRPC were enrolled. Treatment comprised of initial 7 days administration of metronomic cyclophosphamide 50 mg p.o. DCVAC/PCa treatment consisted of a median twelve doses of 1 × 107 dendritic cells per dose injected s.c. (Aldara creme was applied at the site of injection) during a one-year period. The initial 2 doses of DCVAC/PCa were administered at a 2-week interval, followed by the administration of docetaxel (75 mg/m2) and prednisone (5 mg twice daily) given every 3 weeks until toxicity or intolerance was observed. The DCVAC/PCa was then injected every 6 weeks up to the maximum number of doses manufactured from one leukapheresis. RESULTS: No serious DCVAC/PCa-related adverse events have been reported. The median OS was 19 months, whereas the predicted median OS was 11.8 months with the Halabi nomogram and 13 months with the MSKCC nomogram. Kaplan-Meier analyses showed that patients had a lower risk of death compared with both MSKCC (Hazard Ratio 0.26, 95% CI: 0.13-0.51) and Halabi (Hazard Ratio 0.33, 95% CI: 0.17-0.63) predictions. We observed a significant decrease in Tregs in the peripheral blood. The long-term administration of DCVAC/PCa led to the induction and maintenance of PSA specific T cells. We did not identify any immunological parameter that significantly correlated with better OS. CONCLUSIONS: In patients with mCRPC, the combined chemoimmunotherapy with DCVAC/PCa and docetaxel was safe and resulted in longer than expected survival. Concomitant chemotherapy did not preclude the induction of specific anti-tumor cytotoxic T cells.

Structure-activity relationships of novel salicylaldehyde isonicotinoyl hydrazone (SIH) analogs: iron chelation, anti-oxidant and cytotoxic properties.

Salicylaldehyde isonicotinoyl hydrazone (SIH) is a lipophilic, tridentate iron chelator with marked anti-oxidant and modest cytotoxic activity against neoplastic cells. However, it has poor stability in an aqueous environment due to the rapid hydrolysis of its hydrazone bond. In this study, we synthesized a series of new SIH analogs (based on previously described aromatic ketones with improved hydrolytic stability). Their structure-activity relationships were assessed with respect to their stability in plasma, iron chelation efficacy, redox effects and cytotoxic activity against MCF-7 breast adenocarcinoma cells. Furthermore, studies assessed the cytotoxicity of these chelators and their ability to afford protection against hydrogen peroxide-induced oxidative injury in H9c2 cardiomyoblasts. The ligands with a reduced hydrazone bond, or the presence of bulky alkyl substituents near the hydrazone bond, showed severely limited biological activity. The introduction of a bromine substituent increased ligand-induced cytotoxicity to both cancer cells and H9c2 cardiomyoblasts. A similar effect was observed when the phenolic ring was exchanged with pyridine (i.e., changing the ligating site from O, N, O to N, N, O), which led to pro-oxidative effects. In contrast, compounds with long, flexible alkyl chains adjacent to the hydrazone bond exhibited specific cytotoxic effects against MCF-7 breast adenocarcinoma cells and low toxicity against H9c2 cardiomyoblasts. Hence, this study highlights important structure-activity relationships and provides insight into the further development of aroylhydrazone iron chelators with more potent and selective anti-neoplastic effects.

1-Substituted-5-[(3,5-dinitrobenzyl)sulfanyl]-1H-tetrazoles and their isosteric analogs: A new class of selective antitubercular agents active against drug-susceptible and multidrug-resistant mycobacteria.

In this work, a new class of highly potent antituberculosis agents, 1-substituted-5-[(3,5-dinitrobenzyl)sulfanyl]-1H-tetrazoles and their oxa and selanyl analogs, is described. The minimal inhibitory concentration (MIC) values reached 1 µM (0.36-0.44 µg/mL) against Mycobacterium tuberculosis CNCTC My 331/88 and 0.25-1 µM against six multidrug-resistant clinically isolated strains of M. tuberculosis. The antimycobacterial effects of these compounds were highly specific because they were ineffective against all eight bacterial strains and eight fungal strains studied. Furthermore, these compounds exhibited low in vitro toxicity in four mammalian cell lines (IC50 > 30 µM). We also examined the structure-activity relationships of the compounds, particularly the effects on antimycobacterial activity of the number and position of the nitro groups, the linker between tetrazole and benzyl moieties, and the tetrazole itself. Relatively high variability of substituent R(1) on the tetrazole in the absence of negative effects on antimycobacterial activity allows further structural optimization with respect to toxicity and the ADME properties of the 1-substituted-5-[(3,5-dinitrobenzyl)sulfanyl]-1H-tetrazoles lead compounds.