Evaluation of left ventricular short- and long-axis function in severe mitral regurgitation using 2-dimensional strain echocardiography.

BACKGROUND: Few data exist on the changes in left ventricular (LV) short- and long-axis function and their usefulness as markers of LV contractile function in patients with chronic, severe mitral regurgitation (MR). METHODS: We studied 59 patients who had severe MR with an ejection fraction > or =50% and 34 healthy controls. Speckle tracking imaging was performed to measure peak systolic radial (SR(R)), circumferential (SR(C)), and longitudinal strain rates (SR(L)). In all patients, the peak rate of LV pressure rise (peak dP/dt) was measured using a micromanometer-tipped catheter. The patients were subdivided into patients with preserved (group 1, peak dP/dt > or =1,300 mm Hg/s [n = 30]) and depressed (group 2 [n = 29]) contractile function. RESULTS: SR(L) was significantly depressed in groups 1 and 2 when compared with the control group, but there was no difference between groups 1 and 2. In contrast, SR(R) and SR(C) were depressed only in group 2, whereas there were no differences between the control group and group 1. SR(R) and SR(C) correlated well with peak dP/dt (r = 0.71, P <.001 and r = -0.63, P <.001, respectively), whereas SR(L) did not. These findings suggest that LV long-axis function becomes depressed earlier than short-axis function in the chronic remodeling process. CONCLUSIONS: Left ventricular short-axis function is a useful marker of LV contractility in patients with chronic, severe MR. Left ventricular long-axis function becomes depressed earlier in the chronic remodeling process. Therefore, evaluation of short-axis as well as long-axis function might be important for better assessment of LV contractile function in these patients.

Expression spectra of apoptosis-related gene pnas-2 / 中国实验血液学杂志

To explore the expression spectra of apoptosis-related gene pnas-2 in normal tissues and acute leukemia (AL) patient tissues, the expressions of pnas-2 gene in tissues including heart, brain, placenta, lung, liver, skeletal muscle, kidney, pancreas, spleen, lymph node, thymus, leukocyte, bone marrow and fetal liver were detected by Northern blot. The expressions of pnas-2 in samples including 44 de novo, 9 non-CR, 27 CR and 12 relapsed AL patients were measured by real-time RT-PCR and Northern blot, and the expression levels of pnas-2 in normal and tumor tissues from 31 patients with malignancies were also detected. The results showed that pnas-2 was not expressed in the most tissues except in placenta. The results of real-time PCR indicated that pnas-2 expressions in samples of de novo, non-CR and relapsed patients ware significantly higher than that in CR, tumor tissues and normal tissues. In serial monitoring of 7 AL patients, the expression level of pnas-2 was high at first visit examination, but remarkably decreased after remission, and the pnas-2 expression level increased again when relapsed. It is concluded that the pnas-2 is specifically up-regulated in acute leukemia patients, which might be an oncogene and participate in leukemogenesis.

Application of high throughput cell array technology to FISH: investigation of the role of deletion of p16 gene in leukemias.

Bio-cell chip is a chip that has hundreds of types of cells arrayed and immobilized on a small slide. To elucidate the role of deletion of the p16 gene in hematologic malignancies, the bio-cell chip technique was applied to fluorescent in situ hybridization (FISH) study. We made a bio-cell chip with bone marrow specimen from 109 patients with acute lymphoblastic leukemia (ALL), 102 patients with acute myelogenous leukemia (AML), 47 patients with chronic myelogenous leukemia (CML), and 25 patients with multiple myeloma (MM). A glass slide with 96 separated areas was fabricated, onto which was added methanol/acetic acid fixed cell suspensions for high-throughput FISH for p16. With the successful application of bio-cell chip technique, we found that the deletion of p16 contributed to the oncogenesis in acute leukemia, but not in chronic leukemia. In conclusion, the bio-cell chip, a cell version of ultrahigh-throughput technology, was successfully applied to the FISH study, which can be utilized efficiently in the molecular cytogenetic investigation of hematologic malignancies.

Identification of 13q deletion, trisomy 1q, and IgH rearrangement as the most frequent chromosomal changes found in Korean patients with multiple myeloma.

The most frequent genetic aberrations in multiple myeloma (MM) are 13q deletions and translocations involving the immunoglobulin heavy chain gene (IGH). There have been no reports on the cytogenetic abnormalities found in Korean patients with MM. We investigated the actual prevalence and prognostic value of cytogenetic changes using fluorescence in situ hybridization (FISH). FISH studies with 12 different specific probes for the regions containing the genes or chromosome regions (13q, 1q, IGH, p53, MLL, p16, CEP 7, CEP 11, and CEP 12) were performed in 128 patients. The most frequent change found was 13q deletion (48%), followed by trisomy 1q (45%), IGH translocation (37%), and trisomy 11 (26%). Among the three different probes used to detect 13q deletion, D13S25 (48/58) was the most sensitive probe compared to RB (43/58) and D13S319 (39/58). Among the patients showing one or more changes by FISH, 75% (82/110) had a 13q deletion, a trisomy 1q, or an IGH translocation. Azotemia, anemia, thrombocytopenia, intramedullary plasmacytosis, and stage were significantly associated with the 13q deletion; serum beta(2)-microglobulin, thrombocytopenia, and intramedullary plasmacytosis were also related to trisomy 1q. The pattern of molecular cytogenetic changes in Korean patients with MM is somewhat different from what has been observed in reported Caucasian populations: 37 versus 50-70% with regard to the IGH translocation. The prevalence of the 13q deletion was similar in Korean and Caucasian populations, 48 versus 30-50%. We suggest that the detection of at least these three genetic changes, 13q- trisomy 1q, and an IGH rearrangement, would be helpful for follow-up of Korean patients with MM.

Reversal of multidrug resistance of HL-60 adriamycin resistant leukemia cell line by quercetin and its mechanisms / 中华肿瘤杂志

<p><b>OBJECTIVE</b>Quercetin, a widely distributed natural flavonoid with a variety of biological functions, can reverse multidrug resistance (MDR) in leukemia according to recent researches. The aim of this study was to investigate the mechanisms of reversal of multi-drug resistance by quercetin mainly in respect of membrane transporters.</p><p><b>METHODS</b>MTT cell viability assay was used to verify the chemo-sensitization to daunorubicin (DNR) by quercetin in HL-60/ADM cell line and determine the effective reversal concentration, the expression of MRP(1) gene and its protein product, multidrug resistant associated protein 1 by RT-PCR and flow cytometry By confocal laser scanning microscopy, the subcellular distribution of DNR in HL-60/S and HL-60/ADM cells was examined before and after quercetin exposure.</p><p><b>RESULTS</b>Compared with HL-60/S, 20-40 micromol/L quercetin in vitro remarkably enhanced the sensitivity of HL-60/ADM cells to daunorubicin, down-regulated the expression of MRP(1) gene and its protein product MRP(1), restored the abnormal subcellular distribution of daunorubicin, so as to reverse MDR. Moreover, such an effective concentration of quercetin was non-toxic to the cells.</p><p><b>CONCLUSION</b>Quercetin could be a candidate of effective multidrug resistance-reversing agent with low toxicity in leukemia chemotherapy.</p>

Transfection of HL-60 cells with CYP3A5 gene induces drug-resistant phenotype / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate if CYP3A5 gene is involved in the molecular mechanisms for multiple drug resistance in leukemia cells.</p><p><b>METHODS</b>A full length cDNA of CYP3A5 gene was cloned, and a recombinant eukaryotic expression plasmid was constructed, then stably transfected cell lines were established. Furthermore, the sensitivity of those cell lines to several anticancer drugs were assessed by MTT and FCM assay.</p><p><b>RESULTS</b>The recombinant plasmid was designated as pcDNA3-CYP3A5. Transfecting HL-60 cells (which didn't show transcript of CYP3A5 gene) with recombinant plasmid pcDNA3-CYP3A5 generated HL-60/CYP3A5 cell line, and transfecting of HL-60 cells with the parental pcDNA3 vector served as control HL-60/pc cell line. Daunorubicin induced remarkable apoptosis peaks in HL-60 and HL-60/pc cells, while such effect did not occur in HL-60/CYP3A5 cells (apoptosis cell percentage were 7.3%, 6.3% and 1.2%, respectively). Compared with HL-60 and HL-60/pc cells, HL-60/CYP3A5 cells were statistically significantly resistant to daunorubicin, aclacinomycin A, vincristine and harringtonine (resistance multiples were 2.89, 2.01, 4.05 and 2.79 times, respectively, P < 0.05), however the sensitivity to teniposide didn't change (resistance multiple was 1.04 times).</p><p><b>CONCLUSION</b>Transcription of CYP3A5 gene in leukemia cells directly induces resistance to anthracyclines and alkaloids, however the cells are still sensitive to epipodophyllotoxins. Therefore, our findings confirmed a new mechanism of multidrug resistance.</p>

Effect of ATRA and DNR on the expression and secretion of VEGF in leukemic cells / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the expression of VEGF mRNA and secretion of VEGF protein in NB4 and HL-60 cells affected by all-trans retinoic acid (ATRA) and daunorubincin (DNR) respectively.</p><p><b>METHODS</b>Semi-quantitative RT-PCR and ELISA were used to study the expression of VEGF mRNA and secretion of VEGF protein in NB4 and HL-60 cell lines treated by ATRA and DNR respectively.</p><p><b>RESULTS</b>VEGF was expressed in both NB4 and HL-60 cells. The expression of VEGF mRNA and secretion of VEGF protein could be down-regulated by ATRA and DNR respectively in a time and dose dependent manner.</p><p><b>CONCLUSION</b>Besides inducing apoptosis and restraining proliferation of leukemic cells, ATRA and DNR exerted their anti-leukemia effects by reducing angiogenesis via reduction of angiogenic reaction stimulating signals.</p>