Bone Marrow-Derived Cells Participate in Composition of the Satellite Cell Niche in Intact and Regenerating Mouse Skeletal Muscle.

The cellular components of the satellite cell niche participate in the regulation of skeletal muscle regeneration. Beside myogenic cells at different developmental stages, this niche is formed by cells of the immune system, the interstitial connective tissue and the vascular system. Unambiguous determination of the origin of these cell types could contribute to optimization of the cell-based therapy of skeletal muscle disorders. In our work, we intravenously transplanted mouse GFP+ unseparated bone marrow cells into whole-body lethally irradiated immunocompetent mice four weeks before cardiotoxin-induced injury of the recipients' skeletal muscles. Seven and 28 days after the toxin injection, the injured regenerating and contralateral intact muscles were examined for identification of GFP+ bone marrow-derived cells by direct fluorescence, protein immunohistochemistry and immunogold transmission electron microscopy. In both the intact and injured muscles, GFP positivity was determined in immune cells, mainly in macrophages, and in interstitial spindleshaped cells. Moreover, in the injured muscles, rare GFP+ endothelial cells of the blood vessels and newly formed myotubes and muscle fibres were present. Our results confirmed the ability of bone marrowderived cells to contribute to the cellular component of the satellite cell niche in the intact and regenerating skeletal muscle. These cells originated not only from haematopoietic stem cells, but obviously also from other stem or progenitor cells residing in the bone marrow, such as multipotent mesenchymal stromal cells and endothelial progenitors.

Comparison of the Radiosensitizing Effect of ATR, ATM and DNA-PK Kinase Inhibitors on Cervical Carcinoma Cells.

Here, we compared the effects of inhibitors of three phosphatidylinositol-3-kinase-related kinases, ATM, ATR a DNA-PK, on radiosensitization of cervical carcinoma cells. We demonstrated that DNA-PK inhibitor NU7441 enhanced phosphorylation of Chk1 and Chk2 kinases 2 h after irradiation of HeLa cells at a dose of 8 Gy in contrast to ATM kinase inhibitor KU55933, which completely blocked the Chk2 kinase phosphorylation on threonine 68, and ATR kinase inhibitor VE-821, which blocked the Chk1 kinase phosphorylation on serine 345. Most HeLa cells were accumulated in G2 phase of the cell cycle 24 h after irradiation at a high dose of 15 Gy, which was even potentiated after adding the inhibitors NU7441 and KU55933. Compared to all other irradiated groups, inhibitor VE-821 increased the number of cells in S phase and reduced the number of cells in G2 phase 24 h after irradiation at the high dose of 15 Gy. HeLa cells entered the mitotic cycle with unrepaired DNA, which resulted in cell death and the radiosensitizing effect of VE-821. Short-term application of the inhibitors (2 h before and 30 min after the irradiation by the dose of 8 Gy) significantly decreased the colony-forming ability of HeLa cells. Using real-time monitoring of cell proliferation by the xCELLigence system we demonstrated that while the radiosensitizing effect of VE-821 (ATR inhibitor) is manifested early after the irradiation, the radiosensitizing effect of KU55933 (ATM inhibitor) and NU7441 (DNA-PK inhibitor) is only observed as late as 72 h after the irradiation.

Importance of proapoptotic protein PUMA in cell radioresistance.

Protein p53 plays an essential role in the induction of apoptosis by ionizing radiation in haemopoietic cells, the damage of which is the main reason for the development of bone marrow post-irradiation syndrome. p53 activation leads to an increase in the Bcl-2 family pro-apoptotic protein PUMA level. PUMA inhibits all the five anti-apoptotic proteins (Mcl-1, Bcl-2, Bcl-XL, Bcl-W and A1) and directly triggers apoptosis mediated by pro-apoptotic proteins Bax/Bak. In proliferating cells, knockout of p53 inhibits apoptosis on the one hand, but on the other disables the cellular division arrest moderated by p21Cip1/Waf1. The radioprotective effect of p53 inhibitor pifithrin was obvious at radiation doses causing the bone marrow syndrome. Knockout of PUMA also exerts its radioprotective effect through blocking the apoptosis induction, but the arrest of cells in the cell cycle through p21 induction is not abolished. PUMA -/- mice are radioresistant in terms of the development of post-irradiation syndrome after all radiation doses. Small molecules are being searched for that could prevent binding of PUMA with Bcl-2 family anti-apoptotic proteins. This would result in apoptosis inhibition and radioprotective or mitigating effects of these inhibitors.

Assessment of methotrexate hepatotoxicity in psoriasis patients: a prospective evaluation of four serum fibrosis markers.

BACKGROUND: Low-dose oral methotrexate (MTX) is an effective immunosuppressive therapy for chronic plaque psoriasis. However, its use is hampered by the risk of liver fibrosis. AIM: To compare the results of serial measurements of serum fibrosis markers during the remission-induction phase of treatment with MTX to those of patients on biological therapy and long-term MTX therapy (>2 years). SUBJECTS AND METHODS: Serum concentrations of hyaluronic acid, N-terminal propeptide of collagen type III (PIIINP) and the results of two multi-test algorithms Fibrotest and Hepascore were evaluated in patients with chronic plaque psoriasis (N = 24, age: 28-79 years, baseline Psoriasis Area Severity Index PASI 13.5, range 2.2-33) at baseline and weeks 16 and 26 after the start of pharmacokinetically guided therapy with MTX (Group A). Patients on established therapy with biologics (N = 15, Group B) and long-term MTX users (N = 10, Group C) with the mean baseline PASI scores of 0.9 and 1.2 were studied in parallel cohorts. RESULTS: At baseline, HA, Hepascore and PIIINP were correlated with PASI of Group A patients. At weeks 16 and 26, HA decreased by 48% and 40% (P < 0.001) and Hepascore by 31 (P < 0.01) and 20% (P < 0.05) respectively. PASI75 (≥ 75% improvement from baseline PASI) was observed in 76% of Group A patients by week 26 and the absolute decreases in PASI and both fibrosis markers were correlated (HA: r = 0.49, P = 0.018, Hepascore: r = 0.47, P = 0.022). In contrast, no significant within-group differences were found in HA and Hepascore results of patients in the groups B and C. PIIINP and Fibrotest were stable in all groups. CONCLUSION: The fibrosis markers hyaluronic acid and Hepascore (the multiple test algorithm which includes hyaluronic acid) are less liver specific and more prone to reflect psoriasis activity than PIIINP and Fibrotest.

Ionizing radiation induces senescence and differentiation of human dental pulp stem cells.

Head and neck cancer is one of the most common cancers in Europe. Many current anti-cancer treatments, including ionizing radiation, induce apoptosis via DNA damage. Unfortunately, such treatments are non-selective to cancer cells and produce similar toxicity in normal cells, including adult stem cells. One of the fundamental properties of an adult stem cell is that it does not have any tissue-specific structures that allow it to perform specialized functions. However, under certain stimuli, unspecialized adult stem cells can give rise to specialized cells to generate replacements for cells that are lost during one's life or due to injury or disease. Nevertheless, specialization of stem cells must be controlled by specific milieu and also initiated at the proper time, making the entire process beneficial for tissue recovery and maintaining it for a long time. In this paper we assess whether irradiated dental pulp stem cells have maintained open their options to mature into specialized cells, or whether they have lost their unspecialized (immature) state following irradiation. Our findings showed radiation-induced premature differentiation of dental pulp stem cells towards odonto-/osteoblast lineages in vitro. Matrix calcification was visualized from Day 6 or Day 9 following irradiation of cells expressing low or high levels of CD146, respectively.

Valproic acid decreases the reparation capacity of irradiated MOLT-4 cells.

The aim of our work was to evaluate mechanisms leading to radiosensitization of MOLT-4 leukemia cells following valproic acid (VA) treatment. Cells were pretreated with 2 mM VA for 24 h followed by irradiation with a dose of 0.5 or 1 Gy. The effect of both noxae, alone and combined, was detected 1 and 24 hours after the irradiation. Induction of apoptosis was evaluated by a flow cytometry. The extent of DNA damage was further determined by phosphorylation of histone H2AX using confocal microscopy. Changes in protein expression were identified by SDS-PAGE/immunoblotting. Two-millimolar VA increased apoptosis induction after irradiation as well as phosphorylation of H2AX and provokes an increase in the level of p53 and its phosphorylation at Ser392 in 4 h post-irradiation. Likewise, p21 protein reached its maximal expression in 4 h after the irradiation of VA-treated cells. Twenty four hours later, only the p53 phosphorylated at Ser15 was detected. At the same time, the protein mdm2 (negative regulator of p53) was maximally activated. The 24-hour treatment of MOLT-4 leukemia cells with 2 mM VA results in radiosensitizing, increases apoptosis induction, H2AX phosphorylation, and also p53 and p21 activation.

The importance of senescence in ionizing radiation-induced tumour suppression.

Cellular senescence is a condition of longlasting proliferation arrest, induced in cells in response to various stressors. These stressors include telomere shortening and/or dysfunction, DNA damage, and oncogene signalling. Epithelial and mesenchymal cells and also tumour cells derived from these tissues are more resistant to radiation-induced apoptosis and respond to irradiation mainly by senescence. Senescence-associated molecular mechanisms related to the activation of canonical DNA damage pathway ATM-p53 as well as mechanisms related to the extracellular signals, cytokine increase and upregulation of their receptors are discussed in this review.

Hepcidin expression in the liver of mice with implanted tumour reacts to iron deficiency, inflammation and erythropoietin administration.

Cancer is known to be an important cause of anaemia due to several factors including iron deficiency and inflammation. Hepcidin, a key regulator of iron metabolism, is up-regulated by iron and inflammatory stimuli such as interleukin 6, and decreased by iron deficiency, enhanced erythropoiesis and hypoxia. It is supposed to play a crucial role in changes of iron metabolism in anaemia of chronic disease, which is characterized by sequestering iron in macrophages and decreasing its availability for red blood cell production. To study the effect of tumour growth on hepcidin expression, we implanted human melanoma cells into mice and studied the changes of the amount of liver hepcidin mRNA by real-time PCR. We observed development of anaemia, which correlated with the size of the tumour. Hepcidin expression significantly decreased with the anaemia development, but in late stages we observed an increase of its expression together with an increase of mRNA for interleukin 6. However, the increase of hepcidin expression could be inhibited by exogenous erythropoietin administration. In our model of tumour growth, hepcidin expression reflected anaemia development and iron deficiency, erythropoietin administration and inflammation, and we suppose that it could therefore serve as a useful marker of these clinical situations common in cancer patients and play a role in the pathogenesis of cancer-associated anaemia.

Mitoxantrone in combination with a DNA-PK inhibitor: possible therapy of promyelocytic leukaemia resistant forms.

The aim of the study was to sensitize cells of human promyelocytic leukaemia HL-60/MX2 (resistant to mitoxantrone and further substances interacting with topoisomerase II) to the effect of mitoxantrone (MTX). We demonstrated that the main mechanism of the HL-60/MX2 cell atypical multiple drug resistance is not only their altered activity of topoisomerase II and reduced levels of topoisomerase II α and ß proteins. The resistance of the HL-60/ MX2 cells to MTX is associated with their increased ability to repair DNA double-strand breaks (DSBs) in these cells. The HL-60/MX2 cells, compared to HL-60 cells (which are sensitive to MTX effects), contain large amounts of DNA-PK, which is responsible for the main pathway of the DSB repair, nonhomogenous end joining (NHEJ), and they also contain large amounts of further repair proteins Rad50 and Nbs1, which are important in both types of the repair processes (NHEJ as well as homologous recombination). We demonstrated that specific DNAPK inhibitor NU7026 reduced the amount of DNAPK in HL60/MX2, thus preventing the DSB repair through the NHEJ pathway after the incubation with MTX and in this way essentially abolished the resistance of these cells to MTX.

Role of transplanted bone marrow cells in response to skeletal muscle injury.

The recently discovered capacity of bone marrow cells (BMCs) to contribute to injury-induced skeletal muscle regeneration has brought new possibilities in the treatment of skeletal muscle diseases. However, a suitable method of BMC transplantation usable for such therapy has to be established. In this work, recipient mice were intramuscularly injected with cardiotoxin, then whole-body lethally irradiated to eradicate satellite cells in their injured tibialis anterior (TA) muscles and to suppress haematopoiesis, and subsequently intravenously transplanted with lacZ+ BMCs with the aim to investigate the role of exogenous BMCs in response to skeletal muscle injury. Seven to 33 days after grafting, recipient TA muscles were examined to detect donor-derived X-gal+ cells and analysed by quantitative PCR. In injured recipients' muscles, X-gal positivity was identified 14 and 33 days after grafting in some infiltrating neutrophils and macrophages, infrequently in fibroblasts of endomysium, and in many large multinucleated cells (devoid of myogenic markers desmin and nestin) resembling foreign body giant cells situated in the vicinity of necrotic muscle fibres. qPCR confirmed the presence of transplanted lacZ+ BMCs in injured recipients' muscles. Our results proved the ability of intravenously transplanted adult BMCs to settle in injured muscles and generate blood cells that infiltrated endomysium and took part in the cleaning reaction. After inhibition of endogenous myogenesis, BMCs were not able to participate in formation of new muscle fibres due to persisting necrosis of degenerated muscle fibres. Instead, BMCs attempted to resorb necrotic structures, which confirmed the indispensable role of bone marrow-derived macrophages in skeletal muscle regeneration.

Replication of restless legs syndrome loci in three European populations.

BACKGROUND: Restless legs syndrome (RLS) is associated with common variants in three intronic and intergenic regions in MEIS1, BTBD9, and MAP2K5/LBXCOR1 on chromosomes 2p, 6p and 15q. METHODS: Our study investigated these variants in 649 RLS patients and 1230 controls from the Czech Republic (290 cases and 450 controls), Austria (269 cases and 611 controls) and Finland (90 cases and 169 controls). Ten single nucleotide polymorphisms (SNPs) within the three genomic regions were selected according to the results of previous genome-wide scans. Samples were genotyped using Sequenom platforms. RESULTS: We replicated associations for all loci in the combined samples set (rs2300478 in MEIS1, p = 1.26 x 10(-5), odds ratio (OR) = 1.47, rs3923809 in BTBD9, p = 4.11 x 10(-5), OR = 1.58 and rs6494696 in MAP2K5/LBXCOR1, p = 0.04764, OR = 1.27). Analysing only familial cases against all controls, all three loci were significantly associated. Using sporadic cases only, we could confirm the association only with BTBD9. CONCLUSION: Our study shows that variants in these three loci confer consistent disease risks in patients of European descent. Among the known loci, BTBD9 seems to be the most consistent in its effect on RLS across populations and is also most independent of familial clustering.

Gamma-radiation-induced phosphorylation of p53 on serine 15 is dose-dependent in MOLT-4 leukaemia cells.

Molecular indicators of the absorbed dose of ionizing radiation are powerful tools in biodosimetry. The studies reported here were undertaken with the motivation to find such a marker among the mo lecules involved in ataxia-telangiectasia mutated kinase- dependent signalling induced by ionizing radiation (ATM-kinase, checkpoint kinase-2, protein p53, and oncoprotein Mdm2). In our previous work on T-lymphocyte leukaemia MOLT-4 cells we described the mentioned molecules of ATM-dependent pathway and none of them showed a pronounced dosedependent response. Here we employed Western blotting and ELISA assay to investigate the response of post-translationally modified p53 (particularly phosphorylated on serine 15) after gamma-irradiation. We have found the amount of phosphorylated p53 to be homogenously increased after irradiation by the doses of 0.5 to 7.5 Gy. The dose-dependent response was pronounced especially after the doses up to 3.0 Gy. The presented data indicate that p53 phosphorylated on serine 15 might be used as a potential biodosimetric marker.

Capillary immunotyping electrophoresis and high resolution two-dimensional electrophoresis for the detection of mu-heavy chain disease.

Heavy chain disease with monoclonal incomplete mu-heavy chains (mu-HCD) is a rare disorder usually associated with an underlying lymphoproliferative malignancy. Laboratory diagnosis of patients with mu-HCD is usually challenging and the monoclonal protein is not detected by electrophoresis in up to 75% of mu-HCD cases. We describe a patient with multiple malignancies in whom we detected and characterized monoclonal mu-heavy chains using immunofixation electrophoresis, capillary zone electrophoresis with immunotyping, and high resolution two-dimensional electrophoresis. The high resolution 2D electrophoresis enabled us to determine the molecular weight of the mu-heavy chains. The abnormal protein concentration in the serum was unusually high, 38 g/l measured in our patient is the highest reported value in the literature so far.

Antileukemic activity of the combination of ionizing radiation with valproic acid in promyelocytic leukemia cells HL-60.

Valproic acid (VA) possesses anticonvulsant as well as anticancer properties of histondeacetylases inhibitor. Incubation of human promyelocytic leukemia cells HL-60 with VA leads to acetylation of nuclear histones H3 and H4. Using 2 mmol/l concentration we proved the expression of protein p21, which relates to the arrest of cell proliferation and decrease in number of cells in S phase of cell cycle. Treatment of HL-60 cells with VA causes their differentiation, proved as increase in CD11b expression. The most widely used method in cancer treatment is radiotherapy. 24 hours after irradiation by the therapeutical dose of 2 Gy, 56% of HL-60 cells are accumulated in G2 phase of cell cycle. VA had no influence on this accumulation, but 24 h-long pretreatment of cells with 1 mmol/l VA provoked higher decrease in cell number in S phase (18%) comparing with only irradiated cells (25%). The results of our work show that VA posseses radiosensitizing properties when applied 24 hours prior to irradiation and that during parallel long-term action of VA and IR the cells undergo differentiation and faster apoptosis induction. Radiosensitizing effect of VA is not caused by abrogation of G2/M cell cycle arrest, but VA induces p21 and leads to differentiation of HL-60 cells.

The Czech National External Quality Assessment of monoclonal immunoglobulin in the period of 1996 - 2005.

The aim of the presented study was to evaluate the results of SEKK "Gammopathy" (GP) control cycle (Czech National External Quality Assessment) that assessed the success rate of monoclonal immunoglobulin determination by clinical laboratories for the 1996 - 2005 period. The study summarizes the results of 20 "Gammopathy" control cycles during the ten-year period. Control cycles were repeated every 6 months. Patients who provided samples for individual SEKK "Gammopathy" control cycles were selected during routine diagnostic process in the University Hospital Hradec Kralove. Correct paraprotein typing in both A and B control samples (plasma, serum or urine) is required prior to certification. Assessment of paraprotein concentration is optional. The number of participating laboratories was gradually increasing from 26 in 1996 to 79 in 2005 (including 6 Slovak laboratories). The majority of laboratories used immunofixation electrophoresis as the method of paraprotein typing. In 2005, only one laboratory was still using immunoelectrophoresis. Typing was successful in approximately 70% of cases during the first 3 cycles and the success rate gradually increased to almost 96% by 2005. The only exception was GP 1/02 cycle with a sample of relatively rare IgD-lambda paraprotein and the success rate of 38% only. A sample of plasma without paraprotein was distributed 4 times. Several laboratories falsely identified fibrinogen as paraprotein each time. Results of "Gammopathy" control cycle for the past 10 years confirmed the value and legitimacy of this control cycle in the system of external quality control of SEKK laboratories.

Morphological changes of rat jejunum after whole body gamma-irradiation and their impact in biodosimetry.

Gastrointestinal form is the second stage of the Acute Radiation Syndrome (ARS) with a threshold dose of 8 Gy. It represents an absolutely lethal clinical-pathological unit, enteritis necro-hemorrhagica (duodenitis, jejunitis, ileitis, respectively) with unknown causal therapy. The purpose of our study has been to evaluate the morphological changes in a model of radiation-induced enteritis in rats and estimate the significance of changes in biodosimetry. Wistar rats were randomly divided into 21 groups, 10 animals per group. Samples of the jejunum were taken 24, 48, 72, and 96 h after the whole-body gamma-irradiation with the doses of 1, 5, 10, 15, and 20 Gy, and routinely stained with hematoxylin and eosin. Five morphometric markers--intercryptal distance, enterocytal height on the top and base of villus, length of basal lamina of 10 enterocytes and enterocytal width--in irradiated rat jejunum were examined. The results were compared with sham-irradiated control group. After lethal doses of irradiation, all morphometric parameters of jejunum significantly changed. With the exception of intercryptal distance, they might be considered as suitable biodosimetric markers under these experimental conditions. Our morphometry results in radiation-induced jejunitis are in accordance with those in other studies. We were the first who quantified morphological post-irradiation changes in animal jejunum. Some of them might be used under experimental conditions. This experimental study is a predecessor of the clinical assessment of a specific marker. Under clinical practice, the sensitive biodosimetric parameter could serve as one of the guidance for evaluation of the absorbed dose in irradiated troops as well as rescue workers. This is in accordance with tasks and Standardization Agreement of the North Atlantic Treaty Organization.

Expression of phospho-Elk-1 in rat gut after the whole body gamma irradiation.

Gastrointestinal form is the second stage of acute radiation syndrome (ARS) with a threshold dose of 8 Gy in man. It represents an absolutely lethal clinical-pathological unit, necro-hemorrhagic enteritis and proctocolitis, with unknown causal therapy. Elk-1 is a protein acting as a transcription factor activating specified genes. The purpose of our study was to examine the expression of phospho-Elk-1 in irradiated jejunum and transversal colon of rats with radiation-induced enterocolitis and to assess the importance of this transcriptional factor as a biodosimetric marker of radiation-induced enteropathy. The laboratory rats were randomly divided into 21 groups, 10 animals per group, and irradiated with whole body gamma-irradiation of 1, 5, 10, 15, and 20 Gy. Samples of jejunum and transversal colon were taken 24, 48, 72, and 96 hours later, immunohisto-chemically stained, and the phospho-Elk-1 expression was examined using computer image analysis. A group of 10 sham-irradiated animals was used as control. Significantly increased expression of phospho-Elk-1 in rat jejunum has been found in all time intervals after irradiation by sublethal doses of 1 and 5 Gy, whereas after the irradiation by lethal doses, the expression of phospho-Elk-1 in rat jejunum varied considerably. Significantly increased expression of phospho-Elk-1 in transversal colon has also been found in the first days after irradiation by sublethal doses of 1 and 5 Gy. After irradiation by lethal doses, there was no uniform pattern of the changes in the expression of phospho-Elk-1 in rat transversal colon. The detection of phospho-Elk-1 might be considered as a suitable and very sensitive biodosimetric marker of radiation-induced injury of small and large intestine. According to our knowledge, this is the first study on the phospho-Elk-1 expression in irradiated jejunum and transversal colon in the rat.

Effect of somatostatin on repair of ionizing radiation-induced DNA damage in pituitary adenoma cells GH3.

Ionizing radiation and somatostatin analogues are used for acromegaly treatment to achieve normalization or reduction of growth hormone hypersecretion and tumor shrinkage. In this study, we investigated a combination of somatostatin (SS14) with ionizing radiation of (60)Co and its effect on reparation of radiation-induced damage and cell death of somatomammotroph pituitary cells GH3. Doses of gamma-radiation 20-50 Gy were shown to inhibit proliferation and induce apoptosis in GH3 cells regardless of somatostatin presence. It has been found that the D(0) value for GH3 cells was 2.5 Gy. Somatostatin treatment increased radiosensitivity of GH3 cells, so that D(0) value decreased to 2.2 Gy. We detected quick phosphorylation of histone H2A.X upon irradiation by the dose 20 Gy and its colocalization with phosphorylated protein Nbs-1 in the site of double strand break of DNA (DSB). Number of DSB decreased significantly 24 h after irradiation, however, clearly distinguished foci persisted, indicating non repaired DSB, after irradiation alone or after combined treatment by irradiation and SS14. We found that SS14 alone triggers phosphorylation of Nbs1 (p-Nbs1), which correlates with antiproliferative effect of SS14. Irradiation also increased the presence of p-Nbs1. Most intensive phosphorylation of Nbs1 was detected after combined treatment of irradiation and SS14. The decrease of the number of the DSB foci 24 h after treatment shows a significant capacity of repair systems of GH3 cells. In spite of this, large number of unrepaired DSB persists for 24 h after the treatment. We conclude that SS14 does not have a radioprotective effect on somatomammotroph GH3 cells.

CD27(+) peripheral blood B-cells are a useful biodosimetric marker in vitro.

The CD8(+) natural killer (NK) subpopulation has recently been identified as a fast and reliable biodosimetric indicator within human peripheral blood mononuclear cells (PBMC) in vitro. In irradiated and subsequently cultivated PBMC, a decrease of the relative number of intact CD3(-)CD8(+) lymphocytes 16 and 48 h after treatment has allowed for estimating the received dose in the range of 0 - 10 Gy and lethal/sublethal dose discrimination, respectively. Here we show that suitable biodosimeters can also be found in the peripheral blood B-cell compartment. Multiparameter flow cytometric analysis of irradiated and subsequently cultivated human PBMC revealed that both the CD27(+) and CD21(-) B-cell subpopulations can be used as biodosimeters and the CD19(+)CD27(+) lymphocytes have proved useful for retrospective determination of the received dose in the range of 0 - 6 Gy. In addition, several CD19(+) lymphocyte subsets characterized by co expression of CD21, CD27 and CD38 have been shown to bear biodosimetric potential, too. However, when important parameters like the original size within the CD19(+) compartment, its radiation-induced changes and data variation had been taken into account, the CD27(+) subpopulation proved superior to the other B-cell subpopulations and subsets. It appears that, in the dose range of 0 - 6 Gy, the relative decrease of CD27(+) B lymphocytes provides more sensitive and reliable data than that of CD8(+) NK-cells due mainly to lower data variation. In contrast to CD27(+) B cells, the proportions of CD27(+) subpopulations of T-cells were not affected by irradiation. We have also proposed a simple experimental protocol based on full blood cultivation and three-color CD27/CD3/CD19 immuno-phenotyping as a time-saving and inexpensive approach for practical biodosimetric evaluations on simple, three-to-four color flow cytometers.

Lysophosphatidic acid: an ovarian cancer marker.

OBJECTIVE: To determine whether lysophosphatidic acid (LPA) can serve as an ovarian cancer marker, we compared plasma LPA levels in ovarian cancer patients, in women with no ovarian pathology, and in women with benign ovarian tumors. We determined the optimal plasma LPA level cutoff value and correlated clinicopathological parameters with plasma LPA levels. METHOD: Capillary electrophoresis with indirect ultraviolet detection was used to analyze the plasma LPA levels of 133 patients (60 patients with ovarian cancer, 43 women without ovarian pathologies and 30 patients with benign ovarian tumors) during a three-year period. RESULTS: Patients with ovarian cancer had a significantly higher plasma LPA level (n=60, median (med) 16.99 micromnol/l, range 4.53-43.21 micromol/l) compared with controls with no ovarian pathology (n=43, med 2.92 micromol/l, range 0.94-22.93 micromnol/l) and patients with benign ovarian tumor (n=30, med 7.73 micromol/l, range 1.12-28.84 micromol/l) (p < 0.001). We found that plasma LPA levels were associated with the International Federation of Gynecology and Obstetrics (FIGO) stage and ovarian cancer histological type. Patients with endometrial ovarian cancer had significantly higher plasma LPA levels in comparison with other histological types of epithelial ovarian carcinoma. CONCLUSION: The plasma LPA level can be a useful marker for ovarian cancer, particularly in the early stages of disease.