High-resolution chromatin immunoprecipitation (ChIP) sequencing reveals novel binding targets and prognostic role for SOX11 in mantle cell lymphoma.

Sex determining region Y-box 11 (SOX11) expression is specific for mantle cell lymphoma (MCL) as compared with other non-Hodgkin's lymphomas. However, the function and direct-binding targets of SOX11 in MCL are largely unknown. We used high-resolution chromatin immunoprecipitation sequencing to identify the direct target genes of SOX11 in a genome-wide, unbiased manner and elucidate its functional significance. Pathway analysis identified WNT, PKA and TGF-beta signaling pathways as significantly enriched by SOX11-target genes. Quantitative chromatin immunoprecipitation sequencing and promoter reporter assays confirmed that SOX11 directly binds to individual genes and modulates their transcription activities in these pathways in MCL. Functional studies using RNA interference demonstrate that SOX11 directly regulates WNT in MCL. We analyzed SOX11 expression in three independent well-annotated tissue microarrays from the University of Wisconsin (UW), Karolinska Institute and British Columbia Cancer Agency. Our findings suggest that high SOX11 expression is associated with improved survival in a subset of MCL patients, particularly those treated with intensive chemotherapy. Transcriptional regulation of WNT and other biological pathways affected by SOX11-target genes may help explain the impact of SOX11 expression on patient outcomes.

[Large-scale fragmentation of dna and the death of tumor cells by the action of the binary system ascorbic acid-metallocomplexes of cobalt in vitro].

High-molecular-weight DNA fragments are the markers of the early stage of apoptosis induced in eukaryotic cells by cytotoxins of different nature. The dynamics of the development of large-scale DNA fragmentation in K-562 leukemia cells by the action of the antitumor drug, the binary system ascorbic acid--cobalt phthalocyanine within 48 h of incubation, which correspond to two periods of the doubling of cell number in growing control cultures, have been studied. It was shown that, within the first hours of incubation, hydrogen peroxide generated by the system induces the formation of DNA fragments from 2200 to 50 kbp long. Later on the cell death accompanied by a decrease in the content of fragmented DNA is observed. Within 24 h of incubation, part of fragmented DNA remains unrepaired; after 48 h of incubation, a delay or a slowed down proliferation of K-562 cells, which differ from control cells also by a high level of death and a higher content of high-molecular-weight DNA fragments, is observed.

Apoptotic death of human lympholeukemia HL-60 cells resultant from combined effect of cobalt octa-4,5-carboxyphthalocyanine propylenglycol ether and ascorbate.

Cobalt octa-4,5-carboxyphthalocyanine propylenglycol ether proposed for antitumor therapy potentiates the cytotoxic effect of ascorbate on HL-60 human leukemia cells. Combination of these substances caused the formation of H2O2 in the medium and initiated apoptotic death of cells. Catalase abolished the cytotoxic effect of this combination. The results indicate that binary catalytic system of this combination can be regarded as a potential antitumor agent.

Oxidative stress in HEp-2 human laryngeal carcinoma cells induced by combination of vitamins B12b and C.

Incubation of human laryngeal epidermoid carcinoma HEp-2 cells with hydroxocobalamin (vitamin B12b) and ascorbic acid (vitamin C) for 1 h initiated oxidative stress accompanied by damage to mitochondria and increase in intracellular oxidative activity. Studies of the kinetics of these processes showed that the increase in intracellular H2O2 activity and mitochondrial damage are more likely a result, but not the cause of cell apoptosis during the first hour of their incubation with vitamins B12b and C.

Combined treatment with vitamin B12b and ascorbic acid causes in vitro DNA degradation in tumor cells.

Incubation of Ehrlich ascites carcinoma and HEp-2 human epidermoid laryngeal carcinoma cells with hydroxycobalamin (vitamin B12b) and ascorbic acid induced generation and accumulation of double-stranded DNA fragments (23,000 b.p. and longer) in cells. The same vitamins alone in the same concentrations produced no such effects. DNA degradation in HEp-2 cells caused by long-term (4 h) incubation with 5-25 microM hydroxycobalamin and ascorbic acid (1:10-1:40 molar ratio) at 37 degrees C was comparable with that induced by gamma-irradiation in a dose of 150 Gy at 4 degrees C.

[DNA degradation and repair in human laryngeal carcinoma HEp-2 cells after combined exposure to vitamin B12b and ascorbic acid]. / Degradatsiia i reparatsiia DNK v kletkakh épidermoidnoi kartsinomy gortani cheloveka HEp-2 pri sovmestnom deistvii vitamina B12b i askorbinovoi kisloty.

The formation and accumulation of DNA fragments containing no more than 23,000 pairs of bases were observed under exposure of human larynx epidermoid carcinoma cells (Hep-2) to "chemical nuclease", oxycobalamin (vitamin B12b) and ascorbic acid (vitamin C). The obtained DNA damages were repaired more slowly than those induced by gamma-irradiation in the dose adequate to the level of DNA damages. DNA reparation was not revealed after washing the cells from vitamin B12b and ascorbic acid, and in the course of cell incubation with ascorbic acid. Vitamin B12b and ascorbic acid separately did not induce degradation of DNA. DNA damages induced by "chemical nuclease" action precede the cell death observed later.

[Growth inhibition and induction of tumor cell death by phospholipase A2 and lipoxygenase inhibitors]. / Podavlenie rosta i induktsiia gibeli opukholevykh kletok ingibitorami fosfolipazy A2 i lipoksigenazy.

We studied the effect of arachidonic acid metabolism inhibitors in a wide concentration range on the proliferation and death of lympholeukemia cells P-388. Proliferation of the cells was estimated by metaphase frequency and the proportion of cells in S phase; cellular death was determined by their lysis, trypan blue staining, damaged nuclei, the proportion of cells with subdiploid DNA content, and DNA fragmentation. Low concentrations of phospholipase A2 and lipoxygenase inhibitors were shown to stimulate cell division, while higher concentrations inhibited it by blocking G1-S transition and inducing apoptotic cellular death. Indomethacin, a cyclooxygenase inhibitor, had no effect on proliferation and induced no cell death at concentrations up to 10 microM. Inhibitors of phospholipase A2 and lipoxygenase also inhibited tumor growth in mice.

Combined vitamins Bl2b and C induce the glutathione depletion and the death of epidermoid human larynx carcinoma cells HEp-2.

The combination of hydroxocobalamin (vitamin B12b) and ascorbic acid (vitamin C) can cause the death of tumor cells at the concentrations of the components at which they are nontoxic when administered separately. This cytotoxic action on epidermoid human larynx carcinoma cells HEp-2 in vitro is shown to be due to the hydrogen peroxide generated by the combination of vitamins B12b and C. The drop in the glutathione level preceding cell death was found to be the result of combined action of the vitamins. It is supposed that the induction of cell death by combined action of vitamins B12b and C is connected to the damage of the cell redox system.

[The role of intracellular pH in regulation of NS/O myeloma cell growth and death]. / Rol' vnutrikletochnogo pH v reguliatsii rosta i gibeli kletok mielomy NS/O.

Measurements of intracellular pH (pHi) were taken in the course of NS/O myeloma cell proliferation, growth arrest and death. Cell proliferation was shown to take place within a wide range of various pHi values (6.8-7.2), in which cell death could also occur. In dense cultures, after ceasing proliferation the apoptosis pathway of cell death was activated practically without pHi changes. Both proliferation and cell death stimulation were noticed in serum-free medium with apoptosis prevalence up to 72 h. Apoptotic death occurred at various intracellular pH values within the range from 6.5 to 7.2. The data obtained provide the ground to suppose that in contrast to normal cells, the pHi value in NS/O myeloma tumor cells was not a regulator of their proliferation and death. The decrease of cell growth and increase of cell death can take place with put pHi alteration.

[Mechanism of cell death in myeloma NS(O) in culture]. / Mekhanizm gibeli kletok mielomy NS(O) v kul'ture.

We studied in vitro myeloma cell death in a serum-free medium. Spectrophotometric assessment of DNA fragmentation, flow cytometry, and staining by Hoechst dye and ethidium bromide indicate that by the beginning of the third day cell death largely followed the apoptotic pathway. We studied dynamics of intracellular pH (pHi) during the cell death and the relationship between the pHi and apoptosis induction during cultivation in media with different pH. We have shown that decreasing pHi in the course of cell death is a consequence rather than the cause of myeloma cell death. Apoptosis took place at cultivation in the media with pH 6.3 and 8.1; the corresponding pHi values were 6.5 and 7.2, respectively. In the presence of Ca-ionophore A23187 we observed appearance of the cells with aberrant distribution of chromatin and fragmented nucleus; however calcium binding in the media with 5-10 mM EDTA induced even more pronounced nuclei fragmentation. This may indicate that both increased and decreased concentration of intracellular calcium induce NS(O) myeloma cell apoptosis.

[Stimulation of respiration with Piladox in experimental and clinical conditions during administration of drugs for general anesthesia]. / Stimuliatsiia dykhaniia Piladoksom v éksperimente i klinike v usloviiakh primeneniia sredstv dlia obshchei anestezii.

Experimental and clinical studies of the agent Piladox (RGH 2202) were conducted. Experiments on animals (rats, rabbits, mice) demonstrated that Piladox possesses the property of restoring respiration inhibited by narcotic analgesics and some general anesthetics as well as the respiratory-de-priming effect of acute blood loss and is a more effective stimulator of the respiratory center than cordiamine (nikethamide) or corasol. Clinical study of Piladox in 75 patients showed that intravenous infusion of 1 mg/kg of the agent in the awakening period produced a stimulating effect on respiration through increase of its frequency and increase of the respiratory volume. The minute respiratory volume in this case was even greater than the initial values, whereas the CO2 content in the blood and expired air reached the initial level. The hemodynamic values in this period remained generally stable. Piladox does not change the antinociceptive effect of the narcotic analgesics and analgesia in the immediate postoperative period when combined general anesthesia is applied.

[Pharmacokinetic interaction of antibiotics and pathogenetic agents in suppurative meningitis]. / Farmakokineticheskoe vzaimodeistvie antibiotikov i patogeneticheskikh sredstv u bol'nykh gnoinymi meningitami.

The effect of the widely used pathogenetic agents, such as detoxicating fluids and diuretics on the pharmacokinetics of antibiotics, i.e. benzylpenicillin, ampicillin and levomycetin was studied. It was shown that infusion of the detoxicating fluids had an effect on the antibiotic blood levels which depended on the volume of the fluid used. The pharmacokinetics of the antibiotics was found to be changed when the antibiotics were used simultaneously with the diuretics. This is of a special importance for documenting the tactics of antibacterial therapy in patients with meningitis complicated by the brain edema, since intensive dehydration therapy is required in such cases. Significant changes in the pharmacokinetic interaction of the antibiotics with different diuretics, i.e. mannitol, lasix and furosemide were demonstrated. Respective recommendations for the medical practice were developed on the basis of this study.