Katarzyna Kempińska

Synthesis, structure and cytotoxic activity of new acetylenic derivatives of betulin.

A new series of betulin derivatives containing one or two pharmacophores bearing an acetylenic and carbonyl function at the C-3 and/or C-28 positions has been synthesized and characterized by 1H- and 13C-NMR, IR, MS and elemental analyses. The crystal structure of 28-O-propynoylbetulin was determined by X-ray structural analysis. All new compounds, as well as betulin, were tested in vitro for their antiproliferative activity against human SW707 colorectal, CCRF/CEM leukemia, T47D breast cancer, and against murine P388 leukemia and Balb3T3 normal fibroblasts cell lines. Most of the compounds showed better cytotoxicity than betulin and cisplatin used as reference agent. 28-O-Propynoylbetulin was the most potent derivative, being over 500 times more potent than betulin and about 100 times more cytotoxic than cisplatin against the human leukemia (CCRF/CEM) cell line, with an ID50 value of 0.02 μg/mL.

Hydroxyethyl starch as an effective methotrexate carrier in anticancer therapy

At present, effective anticancer therapy remains one of the most challenging tasks facing the scientific community. A major limitation to most conventional low‐molecular weight anticancer chemotherapeutics is their unfavourable uptake by healthy tissue, fast metabolism and lack of tumour cell selectivity. One way to solve this problem is the application of hybrid nanoparticles containing widely known therapeutic substances. This study was performed with the aim of investigating the potential of use hydroxyethyl starch (HES) as a high‐molecular weight carrier for anticancer drug (methotrexate, MTX). HES‐MTX conjugates were characterized in terms of MTX content, hydrodynamic size, zeta potential, and drug release kinetics. In vitro biological characteristics were determined using different cancer cell lines. The antitumor effect in vivo was tested in NOD/SCID mice subcutaneously inoculated with MV‐4‐11 human leukaemia cells and CDF1 mice intraperitoneally inoculated with P388 murine leukaemia cells. The in vivo experiments revealed the considerably higher antitumor efficacy of HES‐MTX conjugates in comparison to unconjugated drug. The results presented in this article demonstrate that the application of HES as an anticancer drug carrier can improve the treatment efficacy and have significant implications for the future design and implementation of drug‐carrier conjugates. The study should help create new opportunities in the design of HES‐based innovative drug‐carrier conjugates.

Efficient human breast cancer xenograft regression after a single treatment with a novel liposomal formulation of epirubicin prepared using the EDTA ion gradient method.

Liposomes act as efficient drug carriers. Recently, epirubicin (EPI) formulation was developed using a novel EDTA ion gradient method for drug encapsulation. This formulation displayed very good stability and drug retention in vitro in a two-year long-term stability experiment. The cryo-TEM images show drug precipitate structures different than ones formed with ammonium sulfate method, which is usually used to encapsulate anthracyclines. Its pharmacokinetic properties and its efficacy in the human breast MDA-MB-231 cancer xenograft model were also determined. The liposomal EPI formulation is eliminated slowly with an AUC of 7.6487, while the free drug has an AUC of only 0.0097. The formulation also had a much higher overall antitumor efficacy than the free drug.

Synthesis of Phosphatidylcholine with Conjugated Linoleic Acid and Studies on Its Cytotoxic Activity

Phospholipids with conjugated linoleic acid (CLA), which are potential lipid prodrugs, were synthesised. CLA was obtained by the alkali-isomerisation of linoleic acid and was subsequently used in the synthesis of 1,2-di(conjugated) linoleoyl-sn-glycero-3-phosphocholine in good (82%) yield. 1-Palmitoyl-2-(conjugated)linoleoyl-sn-glycero-3phosphocholine was obtained by a two-step synthesis in 87% yield. All the compounds were tested in an in vitro cytotoxicityassayagainsttwohumancancercelllines,HL-60andMCF-7,andamousefibroblastcellline,Balb/3T3.The free form of CLA exhibited the highest activity against all cancer cell lines. Results obtained for the Balb/3T3 line proved that phosphatidylcholine derivatives decreased the cytotoxic effect of CLA against healthy cell lines.

Phosphatidylcholine with cis-9,trans-11 and trans-10,cis-12 Conjugated Linoleic Acid Isomers: Synthesis and Cytotoxic Studies

Novel phosphatidylcholines and lysophosphatidylcholines with cis-9,trans-11 and trans-10,cis-12 conjugated linoleic acid (CLA) were synthesized in high yields (75–99 %). The in vitro cytotoxic activities of these compounds against three human cancer cell lines (HL-60, MCF-7, and HT-29) were evaluated. The results revealed that there are differences in the activity between phosphatidylcholine with cis-9,trans-11 and trans-10,cis-12 CLA acyl groups. 1,2-Di(9Z,11E)-octadecadienoyl-sn-glycero-3-phosphocholine was the most potent cytotoxic agent among all tested CLA derivatives and its IC50 (concentration of a compound that inhibits the proliferation of 50 % of the cancer cell population) was 29.4 µM against HL-60. Moreover, phosphatidylcholines with CLA acyls exhibited much lower cytotoxicity against non-cancer cells (Balb/3T3) than free CLA isomers.

Synthesis and antiproliferative activity in vitro of new 2-aminobenzimidazole derivatives. Reaction of 2-arylideneaminobenzimidazole with selected nitriles containing active methylene group

A series of pyrimido[1,2-a]benzimidazole and α-cyanocinnamic acid derivatives have been synthesized in the reactions of Schiff bases 2–7 with selected nitriles containing an active methylene group: malononitrile 8–12, cyanoacetamide 13–16, benzyl cyanide 17–21, benzoylacetonitrile 22–24, cyanoacetate methyl ester 25–28 and benzylacetamide 29. The structures 8–29 were confirmed by the results of elementary analysis and their IR, 1H-, 13C-NMR and MS spectra. The products 8–29 of various chemical structure pyrimido[1,2-a] benzimidazole 8–12, 14–16, 17–21, 23–24, 26 and α-cyanocinnamic acid derivatives 13, 22, 25, 27, 28 were obtained, which are of interest for biological studies or which can be substrates for further synthesis. The selected compounds 10, 13, 14, 17, 19, 21, 23–25 and 28 were screened for their antiproliferative activity in vitro against neoplastic and normal cell lines. The most active two compounds were: 2-(o-bromophenylene)-3-cyano-4-phenyl-1,2-dihydropyrimido[1,2-a]benzimidazole (24) and 3-cyano-4-phenyl-2-(2,4-dimethoxyphenyl)-1,2-dihydropyrimido[1,2-a]benzimidazole (23). However, similarly like cisplatin used as the control, they showed no selectivity towards cancer cells, by inhibiting proliferation of normal mouse fibroblasts in similar manner.

N-Arylaminomethylenebisphosphonates Bearing Fluorine Atoms: Synthesis and Antiosteoporotic Activity

GRAPHICAL ABSTRACT Abstract A series of N-phenyl and N-pyridyl-aminomethylenebisphosphonates substituted in their aromatic rings with fluorine atoms or trifluoromethyl groups have been synthesized by a three component approach. They were screened for potential antiosteoporetic activity using mouse macrophage-like J774E cells. Most of the compounds appeared to be moderate inhibitors of macrophage cells proliferation compared to known the antiosteoporetic drug, Incandronate. Their potency was compared with their structural analogues, hydroxymethylene-bisphosphonate 2 and ethylidenebisphosphonates 3, which appeared to be equipotent. Although the aminomethylenebisphosphonates 1 show low stability in aqueous solutions, the most stable, i.e., N-(3-trifluoromethylphenyl)-aminomethylenebisphosphonic acid, was chosen for in vivo testing on sheep with induced osteoporosis. This compound had marginal influence on the bone structure recovery.

Oral Administration of Polymyxin B Modulates the Activity of Lipooligosaccharide E. coli B against Lung Metastases in Murine Tumor Models

Introduction Polymyxin B (PmB) belongs to the group of cyclic peptide antibiotics, which neutralize the activity of LPS by binding to lipid A. The aim of this study was to analyze the effect of PmB on the biological activity of lipooligosaccharide (LOS E. coli B,rough form of LPS) in vitro and in experimental metastasis models. Results Cultures of murine macrophage J774A.1 cells and murine bone marrow-derived dendritic cells (BM-DC) stimulated in vitro with LOS and supplemented with PmB demonstrated a decrease in inflammatory cytokine production (IL-6, IL-10, TNF-α) and down-regulation of CD40, CD80, CD86 and MHC class II molecule expression. Additionally, PmB suspended in drinking water was given to the C57BL/6 mice seven or five days prior to the intravenous injection of B16 or LLC cells and intraperitoneal application of LOS. This strategy of PmB administration was continued throughout the duration of the experiments (29 or 21 days). In B16 model, statistically significant decrease in the number of metastases in mice treated with PmB and LOS (p<0.01) was found on the 14th day of the experiments, whereas the most intensive changes in surface-antigen expression and ex vivo production of IL-6, IL-1β and TNF-α by peritoneal cells were observed 7 days earlier. By contrast, antigen expression and ex vivo production of IL-6, IL-10, IFN-γ by splenocytes remained relatively high and stable. Statistically significant decrease in LLC metastases number was observed after the application of LOS (p<0.01) and in the group of mice preconditioned by PmB and subsequently treated with LOS (LOS + PmB, p<0.01). Conclusions In conclusion, prolonged in vivo application of PmB was not able to neutralize the LOS-induced immune cell activity but its presence in the organism of treated mice was important in modulation of the LOS-mediated response against the development of metastases.

CCDC 849590: Experimental Crystal Structure Determination

Related Article: Alicja Wzorek, Barbara Gawdzik, Witold Gladkowski, Mariusz Urbaniak, Anita Baranska, Maura Malinska, Krzysztof Woźniak, Katarzyna Kempinska, Joanna Wietrzyk|2013|J.Mol.Struct.|1047|160|doi:10.1016/j.molstruc.2013.05.010

CCDC 849589: Experimental Crystal Structure Determination

Related Article: Alicja Wzorek, Barbara Gawdzik, Witold Gladkowski, Mariusz Urbaniak, Anita Baranska, Maura Malinska, Krzysztof Woźniak, Katarzyna Kempinska, Joanna Wietrzyk|2013|J.Mol.Struct.|1047|160|doi:10.1016/j.molstruc.2013.05.010