[Abnormally lower expression of cmtm5 gene in bone marrow cells from patients with multiple myeloma]

This study was aimed to detect the expression level of cmtm 5 (CKLF-like MARVEL transmembrane domain containing member 5) gene in the bone marrow cells from patients with multiple myeloma (MM), and to investigate the correlation between the expression level of cmtm5 and various clinical characteristics. Real-time quantitative reverse transcription polymerase chain reaction (RQ-RT-PCR) was used to measure the expression levels of cmtm5 gene in the bone marrow cells collected from MM patients, and the MM cell lines, namely, RPMI8226 and CZ1 cells. The normal donor marrow specimens were used as the reference. The ratio of cmtm5 copy number to abl (Abelson murine leukemia viral oncogene homolog) gene copy number was used for indicating the expression level. The results showed that the expression level of cmtm5 gene was significantly down-regulated in bone marrow cells of 51 untreated or relapsed/refractory MM patient as compared to those of normal donor marrow cells (0.047+/-0.062 for the untreated or relapsed/refractory MM patients versus 0.255+/-0.333 for the normal, p<0.01). According to the International Staging System (ISS), the cmtm5 expression level in marrow cells of patients in ISS III stage was significantly lower than that in patients in ISS I stage (0.034+/-0.034 for the ISS III stage versus 0.103+/-0.109 for ISSI stage, p<0.01). Similarly, lower expression levels of cmtm5 gene were also found in two human MM cell lines (0.014+/-0.009 for RPMI8226 cells and 0.004+/-0.006 for CZ1 cells). After the MM patients were effectively treated, their expression levels of cmtm5 gene significantly increased (0.020+/-0.005 for the untreated patients versus 0.227+/-0.038 for the effectively treated patients, p<0.01). A significant negative correlation was observed between the expression level of cmtm5 gene and the number of bone marrow plasma cells (r=-0.307, p<0.05). However, the correlation was not found between the expression level of cmtm5 gene and the clinical characteristics, such as gender, age, hemoglobin level, or M-protein level, etc. It is concluded that the expression level of cmtm5 gene is abnormally lower in the bone marrow cells from the MM patients, and are associated with ISS stages. Furthermore, the expression level of cmtm5 gene is negatively correlated with the number of bone marrow abnormal plasma cells in MM patients, which suggests that the abnormally lower expression of cmtm5 may be involved in the pathogenesis of the MM patients.

Effects of cold stress on the messenger ribonucleic acid levels of peroxisome proliferator-activated receptor-{gamma} in spleen, thymus, and bursa of Fabricius of chickens

This study was to investigate the expression trait of the peroxisome proliferator-activated receptor-gamma (PPAR-gamma) gene and the effect of cold stress on the mRNA levels of PPAR-gamma in spleen, thymus, and bursa of Fabricius of chickens. Eighty-four 1-d-old male chickens were randomly allocated to 12 groups (7 chickens per group). There was 1 control group and 5 treatment groups for acute cold stress and 3 control groups and 3 treatment groups for chronic cold stress. Chickens were maintained in our animal facility, kept under a 16L:8D cycle and temperature (30 +/- 2 degrees C), and given free access to standard chow and water. The cold stress was initiated when the birds were 15 d of age, with the duration of the acute cold stress being 1, 3, 6, 12, and 24 h, and the chronic cold stress was 5, 10, and 20 d, respectively. Cold stress temperature was 12 +/- 1 degrees C. Spleen, thymus, and bursa of Fabricius were collected for the assessment of the mRNA levels by real-time PCR after stress termination. The results showed that the PPAR-gamma gene is expressed in spleen, thymus, and bursa of Fabricius, and its expression level is different in different tissues and at different ages. Acute cold stress significantly decreased (P < 0.05) the mRNA levels of the PPAR-gamma gene of spleen and thymus in all treatment groups and significantly increased (P < 0.05) the mRNA levels of the PPAR-gamma gene of bursa of Fabricius in all treatment groups. Compared with the corresponding control groups, chronic cold stress resulted in a significant increase (P < 0.05) of the mRNA levels of the PPAR-gamma gene in spleen and a significant decrease (P < 0.05) of the mRNA levels of the PPAR-gamma gene in thymus and bursa of Fabricius. The results indicate that the PPAR-gamma gene is expressed in all 3 immune organs and has different expression traits. The magnitude and direction of change in PPAR-gamma gene expression differs with the type of cold stress applied and also varies by tissue.

[Method of measuring sound localization for 4-year-old children on the horizontal plane.]

OBJECTIVE

To investigate the effective way to test 4-year-old children's ability of sound localization in the horizontal plane.

METHODS

Using minimum audible angle (MAA) measure procedure on the basis of conditioned play audiometry, sound localization test was conducted for 4-year-old children at 0 degrees , +/- 45 degrees , +/- 90 degrees , +/- 135 degrees and 180 degrees standard positions in the horizontal plane.

RESULTS

The outcome of sound localization test for 4-year-old children separately were: MAA (0 degrees ) = (3.80 +/- 0.71) degrees , MAA (-45 degrees ) = (7.70 +/- 1.27) degrees , MAA (45 degrees ) = (7.10 +/- 1.39) degrees , MAA (-90 degrees ) = (8.15 +/- 2.38) degrees , MAA (90 degrees ) = (7.61 +/- 2.47) degrees , MAA (-135 degrees ) = (8.85 +/- 2.70) degrees , MAA (135 degrees ) = (8.30 +/- 1.42) degrees , MAA (180 degrees ) = (5.20 +/- 1.27) degrees . The MAA of eight standard positions were less than 10 degrees , and the MAA (0 degrees ) was the smallest one.

CONCLUSIONS

Our findings suggest that MAA test procedure on the basis of conditioned play audiometry could be used to evaluate the ability of sound localization in 4-year-old children.

A novel triple-regulated oncolytic adenovirus carrying PDCD5 gene exerts potent antitumor efficacy on common human leukemic cell lines

PDCD5 (programmed cell death 5) accelerates apoptosis of certain tumor cells and the replication-defective Ad-PDCD5 may be a promising agent for enhancing chemosensitivity. In this study, a triple-regulated conditionally replicating adenoviruses (CRAd) carrying PDCD5 gene expression cassette, SG611-PDCD5, was engineered. In SG611-PDCD5, the E1a gene with a deletion of 24 nucleotides within CR2 region is controlled under the human telomerase reverse transcriptase (hTERT) promoter, the E1b gene expression is directed by the hypoxia response element (HRE), whereas the PDCD5 gene is controlled by the cytomegalovirus promoter. The tumor-selective replication of this virus and its antitumor efficacy were characterized in several leukemic cell lines in vitro and in xenograft models of human leukemic cell line in nude mice. It was found by RQ-RT-PCR assay that SG611-PDCD5 expressed PDCD5 efficiently in leukemic cells. In K562 tumor xenograft models, SG611-PDCD5 displayed a tumor killing capacity. At a dose of 1 x 10(9) plaque-forming units, SG611-PDCD5 alone could completely inhibit the tumor growth and more effective than replication-defective Ad-PDCD5. Histopathologic examination revealed that SG611-PDCD5 administration resulted in leukemic cell apoptosis. We concluded that the triple-regulated SG611-PDCD5, as a more potent and safer antitumor therapeutic, could provide a new strategy for leukemia biotherapy.

[Quantitative analysis of dendritic cell subsets in bone marrow of patients with acute myeloid leukemia]

In order to study the quantity of dendritic cell (DC) subsets of bone marrow in patients with acute myeloid leukemia (AML), the bone marrow aspirate were collected from 77 newly diagnosed AML patients and from 30 healthy persons. The quantity of DC subsets (myeloid dendritic cells, mDC and plasmacytoid dendritic cells, pDC) were detected by flow cytometry and analysed by 3-color and 4-color cytometric gate. Based on the conventional 3-color panel, mDC were identified by Lin-HLA-DR+CD11c+ and pDC were identified by Lin-HLA-DR+CD123+. Based on the 4-color panel, mDC were identified by Lin-HLA-DR+CD11c+ BDCA-1+ and pDC were identified by Lin-HLA-DR+CD123+BDCA-2+. The results showed that a reduction of mDC was found in 74.0% (57/77) and 58.4% (45/77) patients, a reduction of pDC was found in 90.9% (70/77) and 46.8% (36/77) patients respectively by 3-color and 4-color cytometric analysis. Meanwhile an expansion of mDC was showed in 19.5% (15/77) and 22.1% (17/77) patients, an expansion of pDC was showed in 1.3% (1/77) and 27.3% (21/77) patients respectively by 3-color and 4-color cytometric analysis. In subtypes of AML-M2, AML-M3 or AML-M4/5, 81.4%, 100% and 42.1% patients showed mDC decrease and 88.4%, 100% and 89.5% patients showed pDC decrease respectively by 4-color cytometric analysis. It is concluded that the 4-color cytometric gate is better method for detection of mDC and pDC from bone marrow of newly diagnosed AML patients as compared with 3-color cytometric gate, the majority of AML patients showed reduction of mDC and pDC. The percentages of patients with mDC normal or mDC increase in AML-M4/5 subtypes are more than that in AML-M2/3 subtypes, while the pDC does not show difference between AML subtypes.

[Construction and verification of a novel triple-regulated oncolytic adenovirus carrying gene Pdcd5]

The purpose of this study was to construct a recombinant conditionally replicating adenovirus (CRAd) expressing programmed cell death 5 (pdcd5). Pdcd5 gene was inserted in the E3 region of SG600-a CRAd in which the key genes for virus replication E1a and E1b were controlled under the human telomerase reverse transcriptase promoter (hTERTp) and the hypoxia response element (HRE) respectively, and with a deletion of 24 nucleotides within CR2 region of E1a. The insertion and orientation of all recombined plasmids were confirmed by restriction enzyme digestion and polymerase chain reaction (PCR). The infection efficiencies of a recombined virus carrying enhanced green fluorescent protein (EGFP) in leukemic cell lines were observed by using fluorescence microscope. The relative pdcd5 expression levels of K562 after being infected with SG611-pdcd5 were detected by real-time quantitative PCR. The results showed that the construction of SG611-pdcd5 was completed and confirmed. Pdcd5, hTERTp, HRE, skeleton and fiber11 of recombinant adenovirus SG611-pdcd5 were successfully amplified. The infection efficiencies of SG611-EGFP were all above 70% in both leukemic K562 and MEG-01 cell lines. SG611-pdcd5 expressed pdcd5 with high efficiency in leukemic cells as compared with Ad-pdcd5 or SG611 (p < 0.001). The expression level of pdcd5 increased gradually along with the increase of MOI. It is concluded that the triple-regulated adenovirus of SG611-pdcd5 containing the pro-apopro-tic gene pdcd5 has been successfully established with high pdcd5 expression level in leukemic cells, indicating that the recombinant adenovirus, SG611-pdcd5, promises further development of targeted tumor gene therapy.

[Relationship of immunophenotypic features with minimal residual disease detection and gene types in 221 cases of acute promyelocytic leukemia]

This study was aimed to investigate the relationship of immunophenotypic features with minimal residual disease (MRD) detection and gene types in APL patients. Immunophenotypes were analyzed in 221 newly diagnosed APL patients by using four-color flow cytometry. Among of them, CD123 antibody was examined in 87 patients and the fused gene pml-raralpha were detected by PCR in 196 specimens simultaneously. The results of immunophenotyping demonstrated that the positive percentages of CD123, CD33 and CD9 in newly diagnosed APL patients were 100%, 99.1% and 96.0% respectively, and mean percentages of positive cells in positive patients were all around 90%. Although the positive rates of CD117, CD13, CD38 and CD64 were all above 96%, but the mean percentages of positive cells in different positive patients were diverse and average percentages of positive cells were about 70%. CD15, CD56 and CD11b were expressed in some patients, but CD34 and HLA-DR were rarely expressed in the majority of patients, and average positive percentages were all lower. Among 196 newly diagnosed APL patients, bcr1, bcr2 and bcr3 expressions were 63.3%, 4.6% and 32.1% respectively. The results showed a strong correlation of positive expression of CD34 with bcr3 isoform. When cut-off value was chosen as 20%, the proportions of CD34 positive patients in bcr3 and bcr1 cases were 15.4% (10/65) and 3.3% (4/121) separately, which had a significant difference (p < 0.05). When cut-off value was 10%, bcr3 cases had a significantly higher percentage of CD34 positive, compared with bcr1 cases (p < 0.001), which was 47.7% (31/65) and 5.8% (7/121) respectively. However, there was no statistically significant difference on the other antigens between the two groups. Bcr3 isoform was highly indicated when CD34 was positive and non- large side scatter (NL-SSC) was shown in APL cells. It is concluded that there is a unique characteristics of immunophenotyping, and antigens such as CD123, CD33 and CD9 are more applicable to the detection of MRD in APL patients. The positive expression of CD34 and NL-SSC are associated with bcr3 isoform, and the relationship between gene type and antigen expression can be suggested more accurately when the cut-off value is chosen as 10%.

[Expression of 5 genes in CD7 positive acute myeloid leukemia stem/progenitor cells from bone marrow]

This study was aimed to investigate abca5, mdr-1, kdr, dapk and irf-1 expressions in leukemia stem/progenitor cells (LSC) from CD7 positive acute myeloid leukemia, the expression of these 5 genes in mononuclear cells (MNC) from 15 normal bone marrow (NBM) and 16 AML patients bone marrow (AML BM) specimen were detected by real-time quantitative PCR (RQ-PCR). CD34(+)CD38(+) progenitor cells and CD34(+)CD38(-)Lin(-) stem cells were sorted by flow cytometry (FCM) from the MNCs of 10 NBM and 21 AML BM specimen. These 5 gene expressions in the sorted cells were detected by small amount cell RQ-PCR. The results showed that these 5 genes above mentioned all expressed in NBM-MNC, in which the expression levels of irf-1 and dapk were highest with the relative expression levels 4.08 and 3.86, the expression levels of abca 5 and mdr-1 were in the middle with the relative expression 0.49 and 0.84 respectively, the kdr expression was lowest with the relative expression level 0.02. In CD34(+)CD38(+) progenitor cells, the expression level of kdr increased dramatically (p < 0.05) while irf-1 and dapk dramatically decreased (p < 0.05). There was no obvious change of expression in the rest 2 genes. In CD34(+)CD38(-) stem cells the expression level of these 5 genes all increased nearly 2 times as much as that in CD34(+)CD38(+) progenitor cells, but kdr increased 3 times as much, and the increase of kdr and irf-1 expressions was of statistical significance (p < 0.05). Compared with the NBM, expression levels of 5 genes in AML-MNC decreased, and out of them abca 5, mdr-1, kdr and dapk were decreased most remarkably (p < 0.05). Comparison between AML CD34(+)CD38(+) cells and AML MNC showed that the expression level of irf-1 and dapk were decreased dramatically (p < 0.05) while the rest 3 genes increased their expression with statistical significance (p < 0.05). The expression levels of these 5 genes were higher in CD34(+)CD38(-) cells than those in CD34(+)CD38(+) stem cells, and the increase of kdr and irf-1 expressions showed statistical difference (p < 0.05). These 5 genes expression levels were all higher than those in CD34(+)CD38(+) cells whether in AML CD34(+)CD38(-)CD7(+) cells or CD34(+)CD38(-)CD7(-) cells. The increase of kdr expression in CD34(+)CD38(-)CD7(+) cells as well as kdr and irf-1 expressions in CD34(+)CD38(-)CD7(-) cells were all of statistical significance (p < 0.05). In conclusion the expression level of kdr in NBM was highest in stem cells while dapk and irf-1 were highest in differentiated cells. The expression levels of these 5 genes in CD34(+)CD38(-)Lin(-) stem cells were higher than those in CD34(+)CD38(+) progenitor cells. The gene expressions in AML CD34(+)CD38(-)CD7(+) cells and CD34(+)CD38(-)CD7(-) cells are in accordance with the characteristics of stem cells.

Nucleophosmin mutations in Chinese adults with acute myelogenous leukemia

Recently, mutations in the nucleophosmin (NPM1) gene were detected in 50-60% of adult acute myelogenous leukemia (AML) patients, mainly with a normal karyotype. In this study, we detected typical NPM1 mutations (types A, B, D) in untreated Chinese AML patients using real-time quantitative polymerase chain reaction (RQ-PCR) followed by sequence analysis. The detection rate of NPM1 mutations in 220 AML patients was 16.4%, including 107 (14.2%) with the French-American-British (FAB) subtype M2, 43 (2.3%) with M3, and 52 (30.8%) with M4/M5. Only one case each with an NPM1 mutation was detected in four M0, seven M1, five M6, and two M7 cases. Eight patients were followed up after treatment, and five patients in hematologic remission continued to test negative for NPM1 mutations within 2-14 months of follow-up. Sequence analysis revealed that all the 36 positive cases were heterozygous for the mutation with 4-bp insertions at nt 959; the 36 cases included 29 (80.6%) cases with type A, four (11.1%) cases with type B, and one rare DD-3 mutation. We also detected two new mutations, namely, CTCG and CAAG insertions, named BJ-01 and BJ-02, respectively. Further, 38.9% (14/36) patients with NPM1 mutations simultaneously exhibited internal tandem duplications in the FLT3 gene, and 66.7% (22/33) patients did not express CD34. The results demonstrated that RQ-PCR was a reliable and sensitive method for detecting NPM1 mutations, for screening AML, and for the quantitative analysis of minimal residual diseases.

Adenovirus-mediated PDCD5 gene transfer sensitizes K562 cells to apoptosis induced by idarubicin in vitro and in vivo

PDCD5 (programmed cell death 5) accelerates apoptosis of certain tumor cells and is expressed at low levels in marrow-nucleated cells of AML and CML patients. In the present study, we evaluated the effects of PDCD5 overexpression on drug sensitivity of leukemia cells. K562 cells were treated with idarubicin (IDR) alone or in combination with adenoviral vectors expressing PDCD5 (Ad-PDCD5). As shown by annexin-V-FITC/PI dual labeling, apoptosis rates were markedly increased after combined treatment with Ad-PDCD5 compared to IDR treatment alone. We observed that PDCD5 overexpression significantly improves the antitumor effects of low dose IDR treatment in vivo. Tumor sizes were significantly decreased in combined Ad-PDCD5 and low dose IDR treatment groups compared with single IDR treatment groups. Similar results were obtained with combined systemic treatment of Ad-PDCD5 and low dose IDR, and combined treatment with Ad-PDCD5 local injection and low dose IDR i.p. injection. These results indicate that Ad-PDCD5 may be a promising agent for enhancing chemosensitivity.

Twelve polymorphic microsatellites in Oriental river prawn, Macrobrachium nipponense

Oriental river prawn, Macrobrachium nipponense, is a commercially important freshwater prawn species in China, Japan, Korea and Vietnam. Due to overfishing for food, the wild stocks M. nipponense are endangered. Twenty microsatellite loci were isolated from the M. nipponense. Twelve of these loci were polymorphic (seven to 16 alleles per locus), with expected heterozygosity ranging from 0.68 to 0.86 (n = 48). These polymorphic loci provide a valuable tool for assessing genetic diversity of wild and cultured populations.

[Adenovirus-mediated PDCD5 gene transfer sensitizes apoptosis of K562 cells induced by etoposide]

This study was purposed to investigate the effect of adenovirus-mediated transfer of PDCD5 gene on apoptosis of K562 cells induced by etoposide. Recombinant adenovirus PDCD5 (Ad-PDCD5), control vectors Ad-null and Ad-eGFP were constructed by AdMax vector system respectively. After K562 cells were transfected by Ad-PDCD5, Ad-null or Ad-eGFP with different multiplicity of infection (MOI), the expression level of the PDCD5 gene was examined by RQ-RT-PCR assay. The effects of etoposide in combination with Ad-PDCD5 on the proliferation and apoptosis of K562 cells were measured by using MTT assay and flow cytometry with Annexin-V-FITC/PI dual labeling technique, respectively. The results showed that the transfection efficiencies of Ad-eGFP in K562, Jurkat and CEM cells ranged from 60% to 86%. Expression level of PDCD5 gene in K562 cells was evidently increased following transfection with Ad-PDCD5. The Ad-PDCD5 synergistically enhanced the apoptotic percentage of K562 cells induced by VP-16, as compared with that of Ad-null + VP16 and VP-16 alone respectively. It is concluded that Ad-PDCD5 may be a potential agent for enhancing the chemotherapy effect.

[Detection of common fusion transcript levels in untreated leukemia patients by real-time quantitative RT-PCR technique]

OBJECTIVE

To evaluate levels of common specific fusion transcripts M-bcr-abl, m-bcr-abl, TEL-AML1, AML1-ETO, PML-RAR alpha, CBF beta-MYH11 in untreated leukemia patients.

METHODS

Specific fusion transcript levels were detected by TaqMan-based real-time quantitative RT-PCR technique in a total of 208 samples, including 195 bone marrow samples from 50 M-bcr-abl(+) chronic phase-chronic myeloid leukemia (CML-CP), 10 M-bcr-abl(+) acute lymphoblastic leukemia (ALL), 19 m-bcr-abl(+) ALL, 11 TEL-AML1(+) ALL, 30 AML1-ETO(+) acute myeloid leukemia (AML), 58 PML-RAR alpha(+) acute promyelocytic leukemia (APL) and 17 CBF beta-MYH11(+) AML patients and 13 peripheral blood samples from 13 M-bcr-abl(+) CML-CP patients. abl was chosen as internal control gene. Fusion transcript level was calculated as fusion transcript copies/abl transcript copies in percentage.

RESULTS

Bone marrow and peripheral blood samples of CML-CP patients had similar M-bcr-abl fusion transcript levels (median 30% vs 35%, P > 0.05). M- and m-bcr-abl (median 64% vs 54%) levels were similar in ALL patients (P > 0.05), M-bcr-abl level was significantly higher in ALL than CML-CP patients(P < 0.001). Median TEL-AML1 level was 228% in ALL patients. Among AML patients, AML1-ETO level was significantly higher than CBF beta-MYH11 and PML-RAR alpha levels (median 388% vs 145%, 388% vs 47%, all P < 0.001), CBF beta-MYH11 level was significantly higher than PML-RAR alpha level (P < 0.001). Fusion transcript levels of L-, V- and S-type PML-RAR alpha were 45%, 44% and 55%, respectively. L-type was significantly lower than S-type (P = 0.04).

CONCLUSIONS

Fusion transcript levels in untreated leukemia patients were different and patient-to-patient variations did exist. Detection of fusion transcript levels in untreated leukemia patients not only provides baseline for minimal residual disease monitoring and treatment evaluation but also enable the comparison in inter-laboratory data.

[Abnormal expression of PDCD5 in the bone marrow cells of adult acute myeloid leukemia]

The objective of this study was to estimate a novel apoptosis-promoting molecule PDCD5 expression in the bone marrow cells from adult acute myeloid leukemia (AML) for investigation of its significance in the pathogenesis of AML. Flow cytometry assay was used for detection of PDCD5 expression in the different groups of cells from bone marrow of AML patients and normal controls by using 21 monoclonal antibodies with different fluorescent markers. The PDCD5 expressions in bone marrow cells from some AML patients and normal controls were also detected by Western blot. The results showed that the mean PDCD5 fluorescence intensity in bone marrow nucleated cells (MNC) from the bone marrow of 36 untreated AML patients was significantly lower than that from the bone marrow of 30 normal controls (3059 +/- 1392) vs (7432 +/- 1261) (P < 0.01). The mean PDCD5 fluorescence intensity was lower in the marrow granulocytes, monocytes, blast cells, and lymphocytes from untreated AML patients than that from normal (3939 +/- 2121) vs (8367 +/- 1045); (3156 +/- 1635) vs (5917 +/- 2329); (2824 +/- 1592) vs (3998 +/- 2106); (1474 +/- 816) vs (3355 +/- 2042) respectively, (all P < 0.01). Western blot analysis demonstrated that PDCD5 expression was significantly decreased in the AML cells, as compared with normal cells. It is concluded that PDCD5 expression in MNC in untreated AML patients is lower than that in the normal. PDCD5 expression in the marrow granulocytes, monocytes, blast cells, and lymphocytes of untreated AML patients is significantly lower than that in the normal. It suggests that the abnormally low expression of PDCD5 may be involved in the pathogenesis of AML.

[Detection of PML/RARalpha gene transcripts in 46 newly diagnosed acute promyelocytic leukemia patients by real-time quantitative reverse-transcription polymerase chain reaction]

In order to explore the application of real-time quantitative reverse-transcription polymerase chain reaction (Q-PCR) for detecting PML/RARalpha gene transcripts in patients with acute promyelocytic leukemia (APL), the bone marrow samples from 46 newly diagnosed APL patients were collected for analysis. Three plasmids containing cDNA fragments of the bcr1-, bcr3-form PML/RARalpha and ABL control gene were constructed respectively. The ABI Prism 7500 Sequence Detection System using Taqman fluorogenic probes was used to quantify target gene. PML/RARalpha mRNA was detected by Q-PCR in 46 APL patients and 40 non-APL patients. The normalized quotient (NQ) of PML/RARalpha mRNA was calculated as followings: NQ = PML/RARalpha mRNA copy numbers/ABL mRNA copy numbers. Immunophenotype of acute promyelocytic leukemia was determined by four-color flow cytometry. The results showed that the coefficients of variation (CV) of inter-day assay and intra-day assay by using Q-PCR were 1.58% and 0.88% respectively. Q-PCR could detect reproducibly 5 copies of target gene per 100 ng RNA and no pseudopositive results were found. The median NQ of PML/RARalpha mRNA was 0.450 (0.084 - 1.082) in 46 APL patients. There was no indication of any correlation of PML/RARalpha mRNA type with age, sex, hemoglobin, platelet count, percentage of promyelocytes in bone marrow detected by morphology or flow cytometry, PML/RARalpha NQ, or signs of clinically diagnosed coagulation/bleeding disorders. Compared with bcr1-form cases, bcr3-form cases had more M(3v) phenotype (42.9% vs 9.4%, P = 0.015) and higher WBC count (9.35 x 10(9)/L vs 2.15 x 10(9)/L, P = 0.038). APL cells could be classified into large side scatter population (L-SSC) and non-large side scatter population (NL-SSC) in CD45/SSC histogram of flow cytometry. 87.50% patients with bcr1-form showed L-SSC phenotype and 64.29% patients with bcr3-form showed NL-SSC phenotype. It is concluded that a sensitive Q-PCR method is established. The median NQ of PML/RARalpha mRNA was 0.450 in newly diagnosed APL patients. There was no significant difference about PML/RARalpha mRNA expression of both bcr3-form and bcr1-form APL patients. Type of PML/RARalpha transcripts is related with the morphology and immunophenotype.

Comparative genomic hybridization: comparison between esophageal squamous cell carcinoma and gastric cardia adenocarcinoma from a high-incidence area for both cancers in Henan, northern China

Esophageal squamous cell carcinoma (SCC) remains the leading cause of cancer related deaths in Linzhou (formerly Linxian), the highest incidence area for esophageal cancer (EC) in Henan, northern China. In China, gastric cardia adenocarcinoma (GCA) shares very similar geographic distribution with SCC, suggesting the possibility of similar risk factors involved in SCC and GCA carcinogenesis in these areas. However, the underlying genetic alterations for esophageal and gastric cardia carcinogenesis, especially for the molecular difference between SCC and GCA, are largely unknown. The present study was thus undertaken to determine the difference in chromosomal aberrations in SCC (n = 37) and GCA (n = 31) using the comparative genomic hybridization method (CGH). All the patients were from Linzhou, Henan, a high-risk geographic region for both SCC and GCA. CGH results showed that chromosomal aberrations with different degrees were identified both in SCC and GCA. In SCC, chromosomal profile of DNA copy number was characterized by most frequently detected gains at 8q (29/37, 78%), 3q (24/37, 65%) and 5p (19/37, 51%); and frequently detected losses at 3p (21/37, 57%), 8p and 9q (14/37, 38%). In GCA, the frequently detected gains were identified at 20q (13/31, 42%), 6q (12/31, 39%) and 8q (11/31, 35%); the DNA copy number losses in GCA occurred frequently at 17p (17/31, 55%), 19p (15/31, 48%) and 1p (14/31, 45%). Statistically, there were evident differences between SCC and GCA in DNA copy number gains at 8q, 3q, 5p and 20q (P < 0.05) and in losses at 3p, 8p, 5q, 17p and 18q (P < 0.05). Gains at 8q were frequently observed in both SCC and GCA. Gains at 3q and 8p were frequently observed in TNM stage III of both SCC and GCA. The present CGH results provide candidate regions that may contain specific related genes involved in SCC and GCA in the Linzhou population. Gains at 8q, 3q and 5p and losses at 3p, 8p and 9q were specifically implicated in SCC; gains at 20q, 6q and 8q and losses at 17p, 19p and 1p were specifically implicated in GCA; gains at 8q were implicated in both SCC and GCA.

[Detection of phosphotyrosine in bcr-abl-positive cells with PY20 antibody and its clinical applications]

OBJECTIVE

To explore the specificity of anti-phosphotyrosine monoclonal antibody PY20 in bcr-abl+ cells and its possible clinical applications.

METHODS

Bcr-abl cell lines( K562, MEG-01) and bcr-abl- cells lines( Jurkat, MCF-7 )were stained with PY20. Phosphotyrosine protein of K562 and MEG-01 cells was detected by flow cytometry before and after treatment with imatinib. Phosphotyrosine protein in bone marrow cells from 49 patients with chronic myeloid leukemia (CML), Ph+ acute lymphoblastic leukemia(Ph(+) -ALL), Ph- ALL, acute myeloid leukemia (AML-M1, M2, M3, M5, FAB classification), chronic lymphocytic leukemia (CML) and 3 normal donor. Positive cells over 5% of total cells was considered positive cases for phosphotyrosine protein. The level of tyrosine phosphorylation was determined by median fluorescence intensity (MFI).

RESULTS

Bcr-abl cell lines and marrow cells from 10 CML patients and 8 ALL patients were all PY20-positive, while bcr-abl- cell lines and marrow cells from 18 leukemia patients and 3 normal donor were all PY20-negative. MFI decreased remarkably after blocked by imatinib in K562 cells and MEG-01 cells. The positive cell percent of marrow cells from 10 newly diagnosed CML patients and 9 imatinib-sensitive CML patients was (54.20 +/- 19.82)% and (14.84 +/- 6.17)% (P < 0.05), while that of 2 cases of imatinib-resistant was 64.3% and 57.2%. There was significant difference of MFI between imatinib-resistant patients and imatinib-sensitive patients (99.42 +/- 4.87 vs 46.41 +/- 4.67, P < 0.01).

CONCLUSION

PY20 monoclonal antibody is highly specific for bcr-abl+ cells. It might be useful in rapid detection of bcr-abl+ cells and sensitivity to imatinib of CML patients.

[Application of CD123 in detection of minimal residual disease in acute promyelocytic leukemia]

The study was aimed to investigate the role and significance of CD123 with other immunological markers in detecting minimal residual disease (MRD) of APL patients. The immunophenotypes of 186 newly diagnosed APL patients and the percentages of cells identical with APL cell immunophenotypes in 20 normal bone marrow samples were analyzed using four-color flow cytometry. MRD in 172 specimens were monitored by mainly using CD34/CD117/CD123/HLA-DR four-color antibody panels, meanwhile 18 specimens were analyzed with the second antibody combination: CD9/CD117/CD34/CD33, simultaneously and the results were compared with real-time PCR. One hundred and sixteen of 172 bone marrow (BM) or peripheral blood (PB) specimens were from follow-up 19 newly diagnosed APL patients and the rest 56 samples were from 47 patients treated 3 to 24 months later. Among them, 117 samples and 55 samples were collected after achieving morphologic complete remission (mCR) and before achieving mCR respectively. The results of immunophenotyping demonstrated that except CD9, CD33 and CD117 were high-expressed and CD34 and HLA-DR were rarely expressed, the CD123 was expressed in 30/30 (100%) APL patients. The percentages of CD117(+)CD34(-)CD123(+)HLA-DR(-) and CD117(+)CD34(-)CD9(+)CD33(+) cells in nucleated cells were 0.066% +/- 0.012% and 0.089% +/- 0.066% in 20 normal bone marrow samples. The median time of achieving morphology complete remission in 19 APL patients was 4 weeks (3 - 6 weeks). The median time of FCM and PCR results turned to be negative in 13 APL patients was 7.5 weeks (5 - 11) and the median time of PCR results turned to be negative in 11 APL patients was 8 weeks (5 - 12). 41/117 (35.04%) samples were MRD positive by FCM after achieving mCR. The ratio of CD117(+)CD34(-)CD123(+)HLA-DR(-) cells was < 5% in 33 specimens, but > 5% in another 8 specimens, their median percentages of CD117(+)CD34(-)CD123(+)HLA-DR(-) cells were 0.48% (range 0.02% - 4.70%) and 9.02% (range 5.26% - 18.14%) respectively. The median relative percentages of CD123(+)HLA-DR(-) cells in CD117(+)CD34(-) population were 63.59% (range 15.11% - 98.36%) and 86.77% (range 63.29% - 92.62%) respectively. In FCM MRD positive samples, 95.9% (93/97) were PCR positive, the false positive rate of FCM and the false negative rate of PCR were 4.1% (4/97) and 8.75% (7/93) respectively. In FCM negative samples, 92% (69/75) were PCR negative and 8% (6/75) were PCR positive. The percentages of CD117(+)CD34(-)CD123(+)HLA-DR(-) cells in 116 consecutive specimens and 117 specimens of mCR were related to PML/RARalpha quantified by real-time PCR (r = 0.824, P < 0.001 and r = 0.754, P < 0.001 respectively). It is concluded that the detection of APL patients by means of two sets of antibody panels is simple and suitable, which is complementary to PCR in monitoring MRD of APL patients.

Abnormal expression of the programmed cell death 5 gene in acute and chronic myeloid leukemia

To clarify whether expression of the programmed cell death 5 (PDCD5) gene in leukemic cells is abnormal, real-time quantitative reverse transcription polymerase chain reaction (RQ-RT-PCR) was used to examine its expression in marrow cells from leukemia patients. We found lower PDCD5 in both AML and CML marrow cells than in normal donor marrow cells. A negative correlation was found between relative levels of PDCD5 and BCR/ABL expression in all CML patients and in CML patients in the advanced phase. Treatment with the ABL tyrosine kinase inhibitor Imatinib mesylate increased PDCD5 expression in K562 and MEG-01 cells. These findings suggest that abnormal expression of PDCD5 in leukemia may be involved in the pathomechanism of AML and CML.

Tyrosine kinase receptor immunoreactivity in trigeminal mesencephalic and motor neurons following transection of masseteric nerve of the rat

Neurotrophins are known to promote survival after neural injury. To determine the relative importance of tyrosine kinase receptors on the survival of axotomized trigeminal nuclear neurons, we examined the temporal expression profile of tyrosine kinase A, tyrosine kinase B and tyrosine kinase C receptors in the mesencephalic trigeminal nucleus and the motor trigeminal nucleus following transection of the masseteric nerve in rats. Axotomized neurons in these nuclei were retrogradely identified with FluoroGold. We found increase in tyrosine kinase A-immunoreactive mesencephalic trigeminal nucleus neurons in the second week after axotomy but no change in the number of tyrosine kinase A-immunoreactive motor trigeminal nucleus neurons. There was no change in the number of tyrosine kinase B-immunoreactive mesencephalic trigeminal nucleus neurons but the significant increase of tyrosine kinase B-immunoreactive motor trigeminal nucleus neurons throughout the period of observation (3 weeks) peaked at approximately 1 week after axotomy. There was no alteration in the number of tyrosine kinase C-immunoreactive mesencephalic trigeminal nucleus neurons but significant increase in tyrosine kinase C-immunoreactive motor trigeminal nucleus neurons observable by 4 days post-axotomy was followed by decline to levels lower than the control in 2 weeks. Temporal changes in the expression of individual tyrosine kinase receptors in mesencephalic trigeminal nucleus and motor trigeminal nucleus neurons following transection of the masseteric nerve suggest differential contribution of tyrosine kinase-specific neurotrophins to the survival of these neurons after axotomy.