The loss of hormonal dependency in breast tumor cells is often accompanied by epithelial-mesenchymal transition (EMT) features and an increase in cell metastasizing and invasiveness. Here we studied the role of transcription factors Snail1--the central mediator of EMT, in the progression of hormonal resistance of breast cancer cells. The experiments were performed on the estrogen receptor(ER)-positive estrogen-dependent MCF-7 breast cancer cells, ER-positive estrogen-resistant MCF-7/LS subline generated through long-term cultivation of the parental cells in steroid-free medium, and ER-negative estrogen-resistant HBL-100 breast cancer cells. We found that decrease in the estrogen dependency of breast cancer cells is accompanied by an increase in Snail1 expression and activity, and demonstrated the Snail1 involvement in the negative regulation of ER. NF-kappaB was found to serve as a positive regulator of Snail1 in breast cancer cells, and simultaneous inhibition of NF-kappaB and Snail1 by RNA interference resulted in marked increase of cell response to antiestrogen tamoxifen. In general, the results obtained demonstrate that direct inhibition of NF-kappaB and Snail1 partially restores the estrogen receptor machinery, and show that Snail1 and NF-kappaB may serve as an important targets in the treatment of breast cancer.

Telomerase is a ribonucleoprotein that synthesizes telomeric repeats and identified as a promising target for anticancer therapy. Here we describe a new compound aITEL1296 as a potent telomerase inhibitor. Its inhibitory activity was a bit higher (IC50 = 0,19 +/- 0,02 ng/ml) than that of BIBR1532, one of the most potent telomerase inhibitors known to date. Besides telomerase inhibition aITEL1296 activated apoptotic mechanisms and effectively suppressed proliferation of tumor cell lines (GI50 = 5,0 +/- 0,2 ng/ml for most sensitive cell line LnCap) but not normal fibroblast cell line.

N epsilon-Nitroso-N epsilon- [N'-(2-chloroethyl)carbamoyl]-L-lysine (I) and N epsilon- [N'-(2-chloroethyl)-N'-nitrosocarbamoyl]-L-lysine (II), the isomers being the constituents of antitumor agent Lysomustine, were obtained by RFHPLC. The study of cytotoxicity of the above compounds against K562 cells showed that the lesions induced by isomer (II) produce a significant cytotoxic effect but can be efficiently repaired by the action of MGMT (O6-methylaguanine DNA methyltransferase). Under similar conditions, the lesions induced by isomer (I) produce substantially smaller effect but are weakly if at all repairable by MGMT. The effects of a clinically approved agent Lysomustine, which is the mixture of isomers (I) and (II), are similar to those of isomer (II). The results obtained point to a different chemical nature of DNA lesions induced by two Lysomustine isomers. Our data indicate that Lysomustine and its isomer (II) can be used for in vitro selection of cells expressing MGMT.

Paclitaxel dosage form on nanoparticles of 200-300 nm based on lactic and glycolic acid copolymer was obtained by the co-precipitation method. The possibility of controlled release of paclitaxel at pH 7.4 for 24 h was studied in vitro. Studies on Jurkat/WT human T-lymphoblastic leukemia cells showed that incorporation of paclitaxel in the nanoparticles led to a 4-fold increase of its cytotoxicity (6.8×10(-6) M) in comparison with paclitaxel solution. The efficiency of compositions containing polysorbate-80 was comparable to that of non-modified nanoparticles containing paclitaxel.

The influence of granulocyte colony-stimulating factor (G-CSF) has been studied on a model of bleomycin-induced pulmonary fibrosis. It is established that G-CSF significantly increases infiltration of alveolar and alveolar duct interstitium by inflammation cells (lymphocytes, neutrophils, plasmocytes) and increases collagen deposition in lung under conditions of bleomycin introduction. Simultaneously with profibrotic and anti-inflammation effects, G-CSF increased the content of granulocyte cells in the bone marrow and peripheral blood, which was related to the stimulation of committed granulocyte precursors in the bone marrow.

With an increasing number of long-term breast cancer survivors, the number of patients experiencing anthracycline-induced cardiotoxicity increas too. Anthracycline--and nonanthracycline-induced cardiac toxicity--clinically significant and frequent adverse event of conservative treatment of cancer. Echocardiogram and multigated acquisition (MUGA) scan--modalities that may overlook early changes that could identify patients at risk for anthracycline-related cardiotoxicity. However, monitoring cardiac function before and during therapy, continuous infusions of drugs, limiting lifetime anthracycline dose, using cardioprotectants such as dexrazoxane, and developing lipid formulations, may decreased risk of cardiotoxicity.

Phosphorylation is the universal regulatory mechanism in key physiological processes such as development, cell differentiation, proliferation, survival and malignant transformation. In this review we analyze serine/threonine protein kinases of the Pim (proviral integration of Moloney virus) family that have been initially discovered in experimental lymphomas. We provide data on gene structure, evolution, functions and substrates of Pim protein kinases. Focusing on Pim-1 as the major isoform, we analyze its role in the biology of hematopoietic malignancies. Pim-1 is a pro-proliferative and pro-survival protein kinase. It is constitutively active due to autophosphorylation, and its downstream partners positively regulate the cell cycle. Pim-1 cooperates with c-Myc oncoprotein in leukemogenesis; furthermore, Pim-1, like the Akt protein kinase, prevents cell death. Thus, Pim kinases are regarded as new therapeutic targets. Finally, we present an original test system f or screening of Pim inhibitors. In this test system the growth of a genetically engineered Escherichia coli strain in the presence of kanamycin is dependent on the phosphorylation of aminoglycoside-3' phosphotransferase VIII by Pim-1: pharmacological inhibition of this phosphorylation increases the bacterial cell lysis.

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal neoplasms of the gastrointestinal tract. Analysis of GIST morphology is necessary for selection of primary patients with the high risk of tumor progression for adjuvant treatment with gleevek following complete gross resection of KIT (CD 117)-positive GIST. In this study we've analyzed morphological parameters and survival of 120 GIST patients before target therapy. According to risk stratification of primary GIST by tumor location, size and mitotic index (mitoses per 50 visual fields) 44% of gastric GISTs, 87,5% of small bowel GISTs and 100% of rectum GISTs have been classified as high risk group. There was no significant difference between survival of patients with different type of GIST, Ki-67 proliferative index and presence of necrosis.

The efficacy of intraabdominal chemotherapy in management of local recurrences of colon cancer was studied. Intraabdominal intraoperative and early postoperative chemotherapy made it possible to prolong of the recurrenceless term and to improve the life quality of the patients with local recurrences of colon cancer. There was observed a tendency to increase the five-year survival.

The authors analyse the efficacy of anti-relapse therapy of juvenile recurring respiratory papillomatosis in 87 children aged from 2 to 15 years with the use of indole-3-carbinol. Prior to inclusion into this study, the patients underwent from 2 to 86 (mean 12 +/- 14) surgical interventions for the ablation of papillomas. The average interval between successive relapses of papillomas ranged between 2 weeks and 12 months (mean 4.9 +/- 2.33 months). The patients remained under observation in the clinic during 2 years--6 years 5 months (mean 44.8 +/- 15.93 months). The duration of therapy with indole-3-carbinol varied from 12 weeks to 2 years (mean 8.9 +/- 4.72 months). The stable remission of pathology was documented in 28.7% of the patients within the 2 to 6 year follow-up period. A significant (1.5-10-fold) increase in the duration of interval between successive relapses occurred in 41.1% of the children. In 29.9% of the patients, therapy produced no apparent clinical effect; 18.4% of them showed an insignificant shortening of the interval between relapses that remained unaltered in the remaining 11.5%. No adverse effects of the treatment were recorded. It is concluded that treatment with indole-3-carbinol can be recommended as a starting therapeutic modality for the management of juvenile recurring respiratory papillomatosis and the reduction of the intervals between relapses of the disease.

The aim of our study was to investigate the effect of recombinant human cytokine EMAP II (endothelial monocyte-activating polypeptide II) on the expression of MGMT gene, encoding repair enzyme O6-methylguanine-DNA methyltransferase (MGMT) in human cell cultures. The influence of EMAP II on cell proliferation was performed using routine MTT assay. Identification of MGMT in cell extracts was performed using Western blot analysis. We used cell lines: A102 (fibroblasts), CB-1 (umbilical cord blood stromal cells), 4BL6 (cells derived from peripheral blood). It was shown that cytokine EMAP II caused induction of MGMT expression in studied human cell lines. There was a decrease in cell number at high concentrations of this cytokine. It was found that the presence of cytokine EMAP II in serum-free growth medium leads to increasing of repair enzyme MGMT expression level in human cells in vitro.

Fifty-four (54) breast cancer patients, receiving tamoxifen, were enrolled into an evaluation of the status of the endometrium. Liquid-based cytology and immuno-cytochemical analysis were used for assessment. Our method proved viable in selective screening for differential diagnosis of endometrial pathology and cancer detection.

Brain metastasis is an important issue in modern neurooncology. Our results of combined treatment of brain metastases are presented and available approaches to brain irradiation and chemotherapy are discussed. There is strong evidence to suggest that maximum combinations of approaches might improve treatment efficacy and extend median overall survival to as long as 6 months (p < or = 0.05).

Nanobiotechnology, defined as an arm of a nano-system is a rapidly developing area of medicine. Nanomaterials ranging from 1 to 1000 nm in size offer unique advantages of interaction with biological systems on the molecular level. Nanobiotechnologies can be used in definition, diagnosis and treatment of cancer thus leading to the new development of a new discipline--nanooncology. The potential of nanoparticles to be used in in-vivo tumor visualization, biomolecular profiling of tumor growth factors and targeted drug delivery is being studied. These methods stemming from nanotechnology may soon find a broad application in oncology.