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Aim. Comparative study of the effect of chemotherapeutic drugs (doxorubicin, methotrexate and cisplatin) and TGF-β on the human breast carcinoma MCF-7 cells, sensitive (wt) and resistant (DOX/R) to the doxorubicin action. Methods. Semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was used for the estimation of expression of mRNAs coding for the TGF-β isoforms (TGF-β1 and TGF-β2) and the TGF-β type I and II receptors (TβRI and TβRII). Trypan blue exclusion method was used for measuring cell number and cell viability. Results. The MCF-7(DOX/R) cells were more refractory to the TGFβ1-dependent growth inhibition than the MCF-7(wt) cells. The level of mRNAs coding for TGF-β and its receptors was higher in the untreated MCF-7 (DOX/R) cells comparing to the MCF-7(wt) cells. The expression of mRNA coding for TbRII was decreased in both cell lines treated with doxorubicin, methotrexate and cisplatin, while the down-regulation of mRNA coding for TbRI was revealed only in the MCF-7(DOX/R) cells upon the treatment with doxorubicin and methotrexate. Conclusions. The differential effects of studied anticancer drugs and TGF-β on the doxorubicin-sensitive and -resistant cells have been demonstrated. The elucidation of the molecular mechanisms of escape of the MCF-7 (DOX/R) cells from the growth inhibition by TGF-β requires further investigation. [ABSTRACT FROM AUTHOR]

Aim. To study an anticancer activity and to measure cytological and enzymatic indicators of general toxicity of 4-thiazolidinone-based compounds (Les-3288, Les-3833) in the NK/Ly lymphoma grafted to BALB/C mice. Methods. BALB/C mice were implanted with the ascitic NK/ Ly lymphoma and treated for 14 days with 4-thiazolidinone derivatives – Les-3833 (2.5 mg/kg of bodyweight), Les-3288 (5 mg/kg of bodyweight), a complex of Les-3833 with the polymeric nanocarrier Les-3833+PNC (2.5 mg/kg of bodyweight) in water, and doxorubicin (1 mg/kg of bodyweight) used as a positive control. The lymphoma development was monitored by measuring the amount of ascitic fluid in the treated mice. The effects of the applied compounds were checked after 35 days of tumor growth. Results. A distinct decrease in the amount of the ascite fluid with lymphoma cells was revealed in the treated mice, while a 1.5-fold increase of its amount was detected in the untreated mice of control group. The 4-thiazolidinone derivatives demonstrated much less toxicity, and erythrocytes count stayed normal after 21 days of animal treatment. The development of NK/Ly lymphoma led to an increase in the neutrophils number, while the applied anticancer compounds reduced it significantly. Les-3833 and Les-3288 did not affect the number of lymphocytes over the normal level. The activity of aspartate and alanine aminotransferases in blood serum was elevated on the 14 day of treatment, and returned to the normal level on the 21 day. Conclusion. Novel 4-thiazolidinones Les-3833 and Les-3288 are effective in the treatment of NK/Ly lymphoma grafted to BALB/C mice. These derivatives induced had limited negative side effects in the treated mice. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the effect of new synthetic 4-thiazolidinone derivatives (potential anticancer compounds denoted as 3882, 3288 and 3833) and doxorubicin (positive control) in free form and in their complexes with synthetic polyethylene glycol-containing nanoscale polymeric carrier on the biochemical indicators of nephrotoxicity in blood serum of rats. The concentration of total protein, urea, creatinine, glucose, ions of sodium, potassium, calcium, iron and chloride was measured. It was found that after injection of the investigated compounds, the concentration of sodium cations and chloride anions in blood serum was increased compared with control (untreated animals). Doxorubicin’s injection was accompanied by a decrease in the concentration of iron cations. The concentration of total protein, urea and creatinine decreased under the influence of the studied compounds. Complexation of these аntineoplastic substances with a synthetic polymeric nanocarrier lowered the concentration of the investigated metabolites substantially compared to the effect of these compounds in free form. The normalization of concentration of total protein, urea and creatinine in blood serum of rats treated with complexes of the studied compounds with the polymeric carrier comparing with increased concentration of these indicators at the introduction of such compounds in free form was found.

Expression of specific proteins involved in regulation of cell proliferation and apoptosis was studied at the initial (7-8 days after tumor inoculation), median (13-14 days), and terminal (20-21 days) stages of murine NK/Ly lymphoma development. Western-blot analysis using antibodies to MEK-ERK signaling pathway, E2F-1/2 and c-Myc, pSTAT1, pSTAT3, pSTAT5, anti-apoptotic Bcl-XL and pro-apoptotic p53 and Rb proteins, as well as active cleaved forms of caspases-3, -6, -7, was carried out to investigate the growth and survival status of NK/Ly cells. There was a marked increase in the expression of E2F-1/2 transcription factors, MAPK signaling cascade and c-Myc, which suggests intensive proliferation of lymphoma cells at terminal stage of tumor development. However, cytomorphological investigation and electrophoretic study of DNA fragmentation have shown degeneration of NK/Ly lymphoma cells and increase in their death. No expression of p53 protein or cleaved forms of caspases-3, -6, -7 was found, which suggests a caspase-independent type of apoptosis in these cells. Ascitic fluid collected at a terminal stage of NK/Ly lymphoma development was significantly weaker in supporting tumor cell growth than ascitic fluid collected at the initial stage of tumor development. It is suggested that uncontrolled cell proliferation at terminal stage of the NK/Ly lymphoma development causes nutrient deprivation and deficiency of specific growth factors in the ascitic fluid, due to overexpression of MEK-ERK, E2F and c-Myc, thereby leading to the induction of apoptosis.

Aim: To compare the capability of methotrexate, cisplatin, doxorubicine and vincristine to induce production of the transforming growth factor beta(1) (TGF-beta(1)) in two cell lines - MCF-7 and T47D - of human breast carcinoma, as well as to study sensitivity of these cells to TGF-beta(1) and mentioned anticancer drugs., Materials and Methods: ELISA for detection of TGF-beta content in conditioned culture media and Western-blot analysis of the proapoptotic p53 and antiapoptotic Bcl-2 proteins were applied., Results: T47D cells showing higher resistance to growth inhibiting effect of TGF-beta(1) were also refractory to cisplatin. There was no difference between MCF-7 and T47D cells in their sensitivity to methotrexate and doxorubicine, although T47D cells were more sensitive to vincristine. It was found that methotrexate and vincristine did not affect TGF-beta(1) production, while doxorubicine used at a dose of 1-100 ug/ml, significantly induced TGF-beta(1) production in both cell lines. p53 expression in T47D cells was higher than in MCF-7 cells where only doxorubicin induced strongly p53 expression. It should be noted, that Bcl-2 was better expressed in MCF-7 cells, while it was almost undetectable in T47D cells., Conclusion: In cells of human mammary carcinoma of MCF-7 and T47D lines doxorubicine, unlike vincristine and methotrexate, in dose depending manner induces production of TGF-beta(1). TGF-beta(1) production in carcinoma cells was associated with doxorubicine-mediated p53 expression in MCF-7 cells or high basal level of p53 in T47D cells. The cells of MCF-7 line were more sensitive to growth inhibition by exogenous TGF-beta(1) and to cisplatine action than T47D cells, but there was no difference between these cell lines in sensitivity to other anticancer drugs.

It was found that milk of clinical healthy women contains sIgA possessing high affinity for the mammalian thymus DNA and DNA-hydrolyzing activity (sIgA-abzymes). Here we present data that such sIgA-abzymes, purified by sequential chromatography on DEAE-fractogel, heparin-sepharose, DNA-cellulose and followed by gel-filtration, are also able to hydrolyse total RNA from E. coli better than plasmid DNA. Besides, such sIgA-abzymes effectively cleaved 18S and 28S ribosomal RNA isolated from human A549 cells. It is noteworthy that the nuclease activity of sIgA-abzymes was significantly inhibited by ATP, while dATP had no effect on it. A potential role of the ribonuclease activity of sIgA-abzymes present in human milk is discussed.

Aim: 1) To investigate the effect of X-rays on expression of Bax, Bad, and Bcl-2 proteins in human breast carcinoma MCF-7 cells, sensitive (MCF-7(wt)) and resistant (MCF-7(DOX/R)) to doxorubicin; 2) to measure X-radiation-induced DNA damage in order to clarify if changes in the expression of those proteins and DNA repair capacity can be responsible for the development of drug-resistance and for altered radio-sensitivity of MCF-7(DOX/R) cells., Methods: Expression of Bax, Bad and Bcl-2 proteins was detected by Western-blot analysis. DNA damage induced by X-radiation and the kinetics of subsequent DNA repair were estimated by alkaline DNA comet assay., Results: We found an increase in the expression of pro-apoptotic Bax and Bad proteins and a decrease in the expression of Bcl-2 protein in MCF-7(wt) cells under the effect of X-radiation, whereas the expression of those proteins was not changed significantly in the irradiated MCF-7(DOX/R) cells. Different pattern of Bcl-2 expression was shown in MCF-7(DOX/R) cells compared with MCF-7(wt) cells. A decreased level of X-radiation-induced DNA damage and an increased DNA repair capacity were revealed in MCF-7(DOX/R) cells compared with MCF-7(wt) cells., Conclusions: The results of our study suggest that a reduced apoptotic response and an increased DNA repair capacity in MCF-7(DOX/R) cells might contribute to the resistance of these cells to X-radiation treatment.

The effect of anticancer drugs on the expression of p53 protein in tumor cells was studied using the Western Blot analysis. Human lung carcinoma cell line A549 and human breast carcinoma cell line MCF7 sensitive (WT) and resistant (DOX/R) to doxorubicin were used. An increase in p53 protein expression was found in A549 and MCF7 (WT) cells treated with cisplatin, methotrexate, and doxorubicin, whereas the level of p53 was not statistically significantly changed in the MCF7 DOX/R cells. In the untreated MCF7 DOX/R cells the level of p53 protein was markedly higher than in the untreated WT MCF7 cells. A potential role of p53 protein in the development of doxorubicin-resistance in carcinoma cells is discussed.

The effect of formyl chemotactic peptide (fCTP, fMet-Leu-Phe), beta-amyloid peptides (beta-AP, 1-42, 1-16 and 25-35), and bradykinin (BK) on functional activity of phagocytic cells has been investigated. Wheat germ agglutinin (WGA) was also used as a model membrane binding agent of polypeptide nature. Murine monocyte-macrophage cell line J774.2 and normal human blood polymorphonuclear (PMN) cells were used as target phagocytic cells. Their activity was quantitatively estimated by measuring phagocytosis of killed yeast cells. Beta-AP (1-41) maximally stimulated phagocytosis at 0.1 microg/ml, BK--at 1.0 microg/ml, and fCTP--at 2.0 microg/ml. Beta-AP (1-16) and beta-AP (25-35) were inactive in used test-systems. Phagocytosis-inducing activity of beta-AP (1-42) and BK reached maximal levels in 2 h and decreased after 4-6 h of incubation. Phagocytosis numbers were compared with the indicators of phagocytic cell activation, such as absorption of neutral red dye, glucose utilization, production of super-oxide anion (NBT-test) and nitrite accumulation (indicator of NO production). NBT-test, which may be related to the killing ability of phagocytic cells towards the ingested objects, was positive only in stimulated PMN leukocytes, while the nitrite accumulation was detected only in stimulated macrophages. Nitrite accumulation in macrophages was markedly induced by lipopolysaccharide and to a lower extent by 0.5 microg/ml beta-AP (1-42). In high dose (5.0 microg/ml) beta-AP suppressed nitrite accumulation in macrophages stimulated by lipopolysaccharide. Other studied peptides were inactive in inducing nitrite accumulation. Transforming growth factor type beta suppressed phagocytic activity of PMN cells activated by beta-AP or WGA. The anti-inflammatory drugs (indomethacin and L-lysine aescinate) inhibited beta-AP (1-42)-induced phagocytosis. The interrelations between the regulatory pathways of BK, beta-AP and fCTP are discussed.

Murine L1210 leukemia cells possessing an increased resistance to cisplatin were found to be refractory to transforming growth factor (TGF)-beta1-induced growth inhibition, while the parental L1210 cells were strongly inhibited by this cytokine. Growth inhibition was estimated on the basis of [3H]thymidine incorporation, cell counting and colony-forming assay. Cisplatin-resistant L1210 cells were also shown to be much more resistant than the parental cells to both cisplatin- and TGF-beta1-induced apoptosis. These results suggest the existence of cross-resistance to cisplatin and TGF-beta1 in the studied leukemia cells.