Usefulness of KIT mutant transcript levels for monitoring measurable residual disease in t (8;21) acute myeloid leukemia

In addition to RUNX1::RUNX1T1 transcript levels, measurable residual disease monitoring using KIT mutant (KITmut ) DNA level is reportedly predictive of relapse in t (8; 21) acute myeloid leukemia (AML). However, the usefulness of KITmut transcript levels remains unknown. A total of 202 bone marrow samples collected at diagnosis and during treatment from 52 t (8; 21) AML patients with KITmut (D816V/H/Y or N822K) were tested for KITmut transcript levels using digital polymerase chain reaction. The individual optimal cutoff values of KITmut were identified by performing receiver operating characteristics curve analysis for relapse at each of the following time points: at diagnosis, after achieving complete remission (CR), and after Course 1 and 2 consolidations. The cutoff values were used to divide the patients into the KITmut -high (KIT_H) group and the KITmut -low (KIT_L) group. The KIT_H patients showed significantly lower relapse-free survival (RFS) and overall survival (OS) rates than the KIT_L patients after Course 1 consolidation (p = 0.0040 and 0.021, respectively) and Course 2 consolidation (p = 0.018 and 0.011, respectively) but not at diagnosis and CR. The <3-log reduction in the RUNX1::RUNX1T1 transcript levels after Course 2 consolidation was an independent adverse prognostic factor for RFS and OS. After Course 2 consolidation, the KIT_H patients with >3-log reduction in the RUNX1::RUNX1T1 transcript levels (11/45; 24.4%) had similar RFS as that of patients with <3-log reduction in the RUNX1::RUNX1T1 transcript levels. The combination of KITmut and RUNX1::RUNX1T1 transcript levels after Course 2 consolidation may improve risk stratification in t (8; 21) AML patient with KIT mutation.

ZNF384 fusion transcript levels for measurable residual disease monitoring in adult B-cell acute lymphoblastic leukemia

Zinc finger protein 384 (ZNF384) rearrangement defined a novel subtype of B-cell acute lymphoblastic leukemia (B-ALL). The prognostic significance of ZNF384 fusion transcript levels represented measurable residual disease remains to be explored. ZNF384 fusions were screened out in 57 adult B-ALL patients at diagnosis by real-time quantitative polymerase chain reaction and their transcript levels were serially monitored during treatment. The reduction of ZNF384 fusion transcript levels at the time of achieving complete remission had no significant impact on survival, whereas its ≥2.5-log reduction were significantly associated with higher relapse free survival (RFS) and overall survival (OS) rates after course 1 consolidation (p = 0.022 and = 0.0083) and course 2 consolidation (p = 0.0025 and = 0.0008). Compared with chemotherapy alone, allogeneic hematopoietic stem cell transplantation (allo-HSCT) significantly improved RFS and OS of patients with <2.5-log reduction after course 1 consolidation (p < 0.0001 and = 0.0002) and course 2 consolidation (p = 0.0003 and = 0.019), whereas exerted no significant effects in patients with ≥2.5-log reduction (all p > 0.05). ZNF384 fusion transcript levels after course 1 and course 2 consolidation strongly predict relapse and survival and may guide whether receiving allo-HSCT in adult B-ALL.

[Comparison of BCR::ABL (P210) mRNA levels detected by dPCR and qPCR methods in patients with chronic myeloid leukemia]

Objective: To compare digital polymerase chain reaction (dPCR) and real-time quantitative PCR (qPCR) measurements of BCR::ABL (P210) mRNA expression in patients with chronic myeloid leukemia (CML) . Methods: In this non-interventional, cross-sectional study, BCR::ABL (P210) mRNA was simultaneously measured by dPCR and qPCR in peripheral blood samples collected from patients with CML who underwent tyrosine kinase inhibitor therapy and who achieved at least a complete cytogenetic response from September 2021 to February 2023 at Peking University People's Hospital. The difference, correlation, and agreement between the two methods were evaluated using the Wilcoxon signed-rank test, Spearman's correlation, and Bland-Altman analysis, respectively. Results: In total, 459 data pairs for BCR::ABL mRNA expression measured by dPCR and qPCR from 356 patients with CML were analyzed. There was a significant difference in BCR::ABL mRNA expression between the two methods (P<0.001). When analyzed by the depth of the molecular response (MR), a significant difference only existed for patients with ≥MR4.5 (P<0.001). No significant difference was observed for those who did not achieve a major MR (no MMR; P=0.922) or for those who achieved a major MR (MMR; P=0.723) or MR4 (P=0.099). There was a moderate correlation between the BCR::ABL mRNA expression between the two methods (r=0.761, P<0.001). However, the correlation gradually weakened or disappeared as the depth of the MR increased (no MMR: r=0.929, P<0.001; MMR: r=0.815, P<0.001; MR4: r=0.408, P<0.001; MR4.5: r=0.176, P=0.176). In addition, the agreement in BCR::ABL mRNA expression between the two methods in those with MR4.5 was weaker than other groups (no MMR: ▉= 0.042, P=0.846; MMR:▉=0.054, P=0.229; MR4:▉=-0.020, P=0.399; MR4.5:▉=-0.219, P<0.001) . Conclusions: dPCR is more accurate than qPCR for measuring BCR::ABL (P210) mRNA expression in patients with CML who achieve a stable deep MR.

High WT1 expression predicted induction chemotherapy failure in acute myeloid leukemia patients with non-favorable cytogenetic risk

The prognostic significance of WT1 expression at diagnosis in acute myeloid leukemia (AML) remains obscure, and subgroup analysis is the way for clarification. We previously reported the results in t(8;21) AML. In this study, 437 consecutive adult AML patients with non-favorable cytogenetic risk were enrolled. All patients were tested WT1 transcript levels using real-time quantitative PCR at diagnosis; AML-related common fusion genes, KMT2A-PTD, FLT3-ITD, NPM1, CEBPA and TP53 mutations were simultaneously tested. 92.4% of patients overexpressed WT1 compared to normal bone marrow. The existence of FLT3-ITD, NPM1 mutation and the absence of CEBPA biallelic mutation were significantly related to higher WT1 expression. The cutoff value for WT1 was determined by performing receiver operating characteristic curve analysis in regard to complete remission (CR) achievement and was used to categorize patients into low-expression (WT1-L) and high-expression (WT1-H) groups. In the entire cohort, WT1-H was significantly associated with a lower 1-course and 2-course CR rate (P < 0.0010 and P = 0.0060) but was not related to relapse-free survival (RFS). Multivariate analysis showed that WT1-H was an independent adverse prognostic factor for both 1-course and 2-course CR achievement. Subgroup analysis was further performed. WT1-H had a significant adverse impact on CR achievement within intermediate-cytogenetic risk, high-cytogenetic risk, ELN-defined-intermediate-risk, normal karyotype, KMT2A rearrangement, FAB-M2, FAB-M5 and NPM1 mutation (+) subgroups, whereas it had no impact within ELN-defined-low-risk, ELN-defined-high-risk, FAB-M4, FLT3-ITD mutation (+) and CEBPA biallelic mutation (+) subgroups. Moreover, WT1-H patients had a significantly lower RFS rate than WT1-L patients within both FAB-M5 and KMT2A rearrangement subgroups (P = 0.010 and 0.028), whereas WT1 had no impact on RFS within other subgroups mentioned above (all P > 0.05). Therefore, high WT1 expression at diagnosis independently predicted induction chemotherapy failure in AML patients with non-favorable cytogenetic risk, and it was related to relapse just within FAB-M5 and KMT2A rearrangement subgroups.

The prognostic significance of CRLF2 expression at diagnosis in adult Ph-negative B-cell precursor acute lymphoblastic leukemia

The prognostic significance of cytokine receptor like factor 2 (CRLF2) expression at diagnosis in adult B-cell precursor acute lymphoblastic leukemia (BCP-ALL) needs to be clarified. A total of 357 bone marrow samples collected from consecutive adult cases with Ph-negative BCP-ALL at diagnosis retrospectively detected CRLF2 transcript levels by real-time quantitative PCR. Twenty percent was selected as the cutoff value for CRLF2 to divide patients into CRLF2_H and CRLF2_L groups. CRLF2_H was associated with higher WBC count, P2RY8-CRLF2 fusion and IKZF1 deletions (IKZF1del). In both the whole cohort and B-other patients, CRLF2_H independently predicted lower CR rates after induction. Furthermore, CRLF2_H/IKZF1del(+) patients had significantly lower CR, RFS, and OS rates and tended to have lower RFS and OS rates than others in the whole cohort and B-other patients, respectively. Therefore, coexistence of CRLF2_H and IKZF1del at diagnosis predicts poor response and outcome in adult Ph-negative BCP-ALL.

Low IL7R Expression at Diagnosis Predicted Relapse in Adult Acute Myeloid Leukemia Patients With t(8;21)

Background

Acute myeloid leukemia (AML) with t(8;21) needs to be further stratified. In addition to leukemia cells, immune cells in tumor microenvironment participate in tumor initiation, growth and progression. Interleukins (ILs)/interleukin receptors (ILRs) interaction plays important roles in the antitumor immune response. IL7R is reported to be relevant to prognosis in solid tumor and acute lymphoblastic leukemia. However, the prognostic significance of IL7R in t(8;21) AML remains to be clarified.

Methods

Bone marrows collected from 156 newly diagnosed t(8;21) AML patients were used for testing IL7R transcript level by TaqMan-based real-time quantitative PCR (RQ-PCR), and RNAseq were performed in 15 of them. Moreover, IL7R expression at diagnosis were measured by RQ-PCR and flow cytometry (FCM) simultaneously in other 13 t(8;21) AML patients.

Results

t(8;21) AML patients had varied IL7R transcript levels and were categorized into low-expression (IL7R-L) and high-expression (IL7R-H) groups; IL7R-L was significantly associated with a lower relapse-free survival (RFS) rate (P=0.0027) and KITD816/D820 mutation (P=0.0010). Furthermore, IL7R-L was associated with a lower RFS rate in KITD816/D820 group (P=0.013) and IL7R-H/KITD816/D820 patients had similar RFS to KITN822/e8/WT patients (P=0.35). GO analysis enrichment showed that down-regulated genes were predominantly involved in the regulation of T cell and leukocyte activation, proliferation and differentiation in IL7R-L group. IL7R-L had significantly lower levels of Granzymes A/B, CCR7, CD28 and CD27 than IL7R-H group (all P&lt;0.05). FCM analysis showed IL7R protein was primarily expressed in CD4+ T and CD8+ T cell subset. A significant association was found between the transcript level of IL7R and the percentage of CD8+ T cells in nucleated cells (P=0.015) but not CD4+ T cells (P=0.47).

Conclusion

Low IL7R transcript level of bone marrow at diagnosis predicted relapse in t(8;21) AML, which might be caused by the difference in the amount, status and function of T cells.

Low EVI1 expression at diagnosis predicted poor outcomes in pediatric Ph-negative B cell precursor acute lymphoblastic leukemia patients

Abnormally high ecotropic viral integration site 1 (EVI1) expression has been recognized as a poor prognostic factor in acute myeloid leukemia patients. However, its prognostic impact in B cell precursor acute lymphoblastic leukemia (BCP-ALL) remains unknown. A total of 176 pediatric Ph-negative BCP-ALL patients who received at least 1 course of chemotherapy and received chemotherapy only during follow-up were retrospectively tested for EVI1 transcript levels by real-time quantitative PCR at diagnosis, and survival analysis was performed. Clinical and EVI1 expression data of 129 pediatric BCP-ALL patients were downloaded from therapeutically applicable research to generate effective treatments (TARGET) database for validation. In our cohort, the median EVI1 transcript level was 0.33% (range, 0.0068-136.2%), and 0.10% was determined to be the optimal cutoff value for patient grouping by receiver operating characteristic curve analysis. Low EVI1 expression (<0.10%) was significantly related to lower 5-year relapse-free survival (RFS) and overall survival (OS) rates (P = 0.017 and 0.018, respectively). Multivariate analysis showed that EVI1 expression <0.10% was an independent adverse prognostic factor for RFS and OS. TARGET data showed that low EVI1 expression tended to be related to a lower 5-year OS rate (P = 0.066). In conclusion, low EVI1 expression at diagnosis could predict poor outcomes in pediatric Ph-negative BCP-ALL patients receiving chemotherapy.Supplemental data for this article is available online at https://doi.org/10.1080/08880018.2021.1939818 .

High PRDM16 expression predicts poor outcomes in adult acute myeloid leukemia patients with intermediate cytogenetic risk: a comprehensive cohort study from a single Chinese center

Acute myeloid leukemia with intermediate cytogenetic risk (ICR-AML) needs to be stratified and abnormal gene expression might be prognostic. PR/SET domain 16 (PRDM16) transcript levels were assessed in 267 consecutive adult ICR-AML patients at diagnosis by real-time quantitative PCR. 38.2% patients had PRDM16 transcript levels higher than the upper limit of normal bone marrow samples. Through ROC curve analysis and comparison of relapse-free survival (RFS), the optimal cutoff value of PRDM16 transcript levels was identified to group patients into high expression (PRDM16-H, 21.3%) and low expression (PRDM16-L). PRDM16-H was significantly associated with lower 4-year RFS and overall survival (OS) rates in the entire cohort, patients with normal karyotypes, FLT3-ITD (-) and NPM1 mutation (+)/FLT3-ITD (-) patients (all p < .05). Multivariate analysis showed that PRDM16-H was an independent adverse prognostic factor for RFS and OS in the entire cohort. Therefore, high PRDM16 expression at diagnosis predicts poor outcomes in adult ICR-AML patients.

Both Methylation and Copy Number Variation Participated in the Varied Expression of PRAME in Multiple Myeloma

Purpose

The cancer-testis antigen, which is a preferentially expressed antigen of melanoma (PRAME), is an ideal target for immunotherapy and cancer vaccines. Since the expression of this antigen is relevant to therapy responses, the heterogeneity in its expression and the underlying mechanism need to be investigated.

Patients and Methods

Plasma cell sorting was performed in 48 newly diagnosed multiple myeloma (MM) patients. Real-time quantitative PCR was performed to examine the PRAME transcript levels and gene copy numbers. Bisulfate clone sequencing of the PRAME promoter and exon 1b regions was performed in 4 patients. Quantitative methylation-specific PCR of the +287 CpG site was performed for all patients. The human MM cell lines RPMI8226, LP-1 and MOLP-2 were treated with 5-azacytidine.

Results

The median PRAME transcript level was 3.1% (range: 0–298.3%) in the plasma cells sorted from the 48 MM patients. Eleven (22.9%) and 37 (77.1%) patients were individually categorized into the PRAME low- and high-expression groups according to the cut-off value of 0.05%. The methylation ratios of the promoter and the 3ʹ region of exon 1b region were both negatively related to the transcript levels. The degrees of methylation at the +287 CpG site were significantly negatively related to the transcript levels in all 48 patients (r=−0.44, P=0.0018), and those in the high-expression group (r=−0.69, P<0.0001) but not those in the low-expression group (r=−0.27, P=0.43). All 5 patients with homozygous deletions were categorized into the low-expression group. There were no significant differences in the PRAME transcript levels between the hemizygous deletion (n=8) and no deletion (n=35) groups (P=0.40). Furthermore, the PRAME transcript levels significantly increased in the MM cell lines after treatment with 5-azacytidine.

Conclusion

Both methylation and copy number variation may participate in the regulation of PRAME expression in MM; in patients with no homozygous deletion, PRAME expression is mainly controlled by methylation, and a proportion of fairly low expression is caused by homozygous deletion.

Reducing Injury During Restraint by Crisis Intervention in Psychiatric Wards in Singapore

OBJECTIVE

The application of restraints during psychiatric crises is a serious adverse event. We aimed to reduce the number of injuries sustained by patients during the application of restraints.

METHODS

Structured interviews were conducted with 10 staff to determine six root causes of patient injury during restraint. Three plan-do-study-act cycles were implemented: (1) reorganising shift rosters to pair trained staff with inexperienced staff, (2) holding monthly session for practising de-escalation and restraint techniques as a team in a supervised setting, and (3) rotating the responsibility for leading the de-escalation in real crises.

RESULTS

Pre-intervention period was from January 2014 to December 2014 (28 251 inpatient bed days). Intervention period was from January 2015 to March 2015 (7121 inpatient bed days). Post-intervention period was from April 2015 to December 2016 (51 735 inpatient bed days). Data extracted included the dates and numbers of crises, activation of the crisis team, use of restraints, and injuries. During pre-intervention and intervention periods, only two minor and three moderate injuries were recorded. During post-intervention period, no injury was recorded and the number of restraints decreased gradually although the number of crisis team activations increased in the early phase. Eventually restraints were used only upon arrival of the crisis team.

CONCLUSION

Our quality improvement project identified six root causes and implemented three plan-do-study-act cycles to successfully eliminated patient injuries during the use of restraints.

[An interlaboratory comparison study on the detection of RUNX1-RUNX1T1 fusion transcript levels and WT1 transcript levels]

Objective: To investigate the current status and real performance of the detection of RUNX1-RUNX1T1 fusion transcript levels and WT1 transcript levels in China through interlaboratory comparison. Methods: Peking University People's Hospital (PKUPH) prepared the samples for comparison. That is, the fresh RUNX1-RUNX1T1 positive (+) bone morrow nucleated cells were serially diluted with RUNX1-RUNX1T1 negative (-) nucleated cells from different patients. Totally 23 sets with 14 different samples per set were prepared. TRIzol reagent was added in each tube and thoroughly mixed with cells for homogenization. Each laboratory simultaneously tested RUNX1-RUNX1T1 and WT1 transcript levels of one set of samples by real-time quantitative PCR method. All transcript levels were reported as the percentage of RUNX1-RUNX1T1 or WT1 transcript copies/ABL copies. Spearman correlation coefficient between the reported transcript levels of each participated laboratory and those of PKUPH was calculated. Results: ①RUNX1-RUNX1T1 comparison: 9 samples were (+) and 5 were (-) , the false negative and positive rates of the 20 participated laboratories were 0 (0/180) and 5% (5/100) , respectively. The reported transcript levels of all 9 positive samples were different among laboratories. The median reported transcript levels of 9 positive samples were from 0.060% to 176.7%, which covered 3.5-log. The ratios of each sample's highest to the lowest reported transcript levels were from 5.5 to 12.3 (one result which obviously deviated from other laboratories' results was not included) , 85% (17/20) of the laboratories had correlation coefficient ≥0.98. ②WT1 comparison: The median reported transcript levels of all 14 samples were from 0.17% to 67.6%, which covered 2.6-log. The ratios of each sample's highest to the lowest reported transcript levels were from 5.3-13.7, 62% (13/21) of the laboratories had correlation coefficient ≥0.98. ③ The relative relationship of the reported RUNX1-RUNX1T1 transcript levels between the participants and PKUPH was not always consistent with that of WT1 transcript levels. Both RUNX1-RUNX1T1 and WT1 transcript levels from 2 and 7 laboratories were individually lower than and higher than those of PKUPH, whereas for the rest 11 laboratories, one transcript level was higher than and the other was lower than that of PKUPH. Conclusion: The reported RUNX1-RUNX1T1 and WT1 transcript levels were different among laboratories for the same sample. Most of the participated laboratories reported highly consistent result with that of PKUPH. The relationship between laboratories of the different transcript levels may not be the same.

Significant prognostic values of nuclear genes encoding mitochondrial complex I subunits in tumor patients

In cancer biology, it remains still open question concerning the oncogenic versus oncosuppressor behavior of metabolic genes, which includes those encoding mitochondrial complex I (CI) subunits. The prognostic value of nuclear genome mRNAs expression of CI subunits is to be evaluated in the tumor patients. We used the Kaplan Meier plotter database, the cBio Cancer Genomics Portal, and the Oncomine in which gene expression data and survival information were from thousands of tumor patients to assess the relevance of nuclear genome mRNAs level of CI subunits to patients' survival, as well as their alterations in gene and expression level in tumors. We presented that the relative expression level of overwhelming majority of the nuclear genes of CI subunits with survival significance (overall survival, relapse free survival, progression free survival, distant metastasis free survival, post progression survival, and first progression), had consistent effects for patients in each type of four tumors separately, including breast cancer, ovarian cancer, lung cancer, and gastric cancer. However, in gene level, frequent cumulative or individual alteration of these genes could not significantly affect patients' survival and the overexpression of the individual gene was not ubiquitous in tumors versus normal tissues. Given that reprogrammed energy metabolism was viewed as an emerging hallmark of tumor, thus tumor patients' survival might potentially to be evaluated by certain threshold for overall expression of CI subunits. Comprehensive understanding of the nuclear genome encoded CI subunits may have guiding significance for the diagnosis and prognosis in tumor patients.

Determination of 23 perfluorinated alkylated substances in water and suspended particles by ultra-performance liquid chromatography/tandem mass spectrometry

A practical multi-residue method based on ultra-performance liquid chromatography/tandem mass spectrometry was developed for the simultaneous determination of 23 perfluorinated alkylated substances (PFASs) in water and suspended particles. Suspended particle samples were extracted with 1% formic acid-acetonitrile and cleaned by matrix solid phase dispersion extraction using a C₁₈ sorbent and graphitized carbon black. Water samples were filtered through 0.7-μm glass fiber membranes and enriched utilizing weak anion exchange cartridges. The eluent was dried under a gentle stream of N₂ at 45°C and suspended in 1 mL acetonitrile-5 mM ammonium acetate (1:1, vol:vol). Gradient elution for chromatographic separation utilized acetonitrile and 5 mM ammonium acetate as mobile phases on a reverse phase C₁₈ column. The compounds were quantified using an internal standard method in multiple reaction-monitoring mode. Limits of detection and quantitation of the 23 PFAS test compounds in water samples were 0.5-10 ng L^-1 and 2-20 ng L^-1, respectively. Recoveries at three fortified levels of 20, 50, and 200 ng L^-1 ranged from 68.5% to 118% with relative standard deviations below 9.6%. We used this method to determine PFAS levels in real water and suspended particle samples and found high sensitivity and good reproducibility.

PRAME Gene Copy Number Variation Is Related to Its Expression in Multiple Myeloma

Multiple myeloma (MM) patients commonly present abnormal expression of cancer-testis antigens, which may serve as immunotherapeutic targets and prognostic factors. We previously reported that preferentially expressed antigen of melanoma (PRAME) overexpression in bone marrow mononuclear cells is related to progression in MM patients treated with non-bortezomib-containing regimens. The mechanism underlying variations in PRAME expression remains unknown. To investigate the impact of gene copy number variation (CNV) on PRAME expression, plasma cells were sorted from 50 newly diagnosed patients and 8 healthy volunteers to measure PRAME transcript levels and gene copy numbers by real-time quantitative polymerase chain reaction. A total of 14 (28.0%), 7 (14.0%), and 29 (58.0%) patients exhibited overexpression, expression within the normal range, and low expression, respectively. PRAME overexpression was significantly related to a lower 1-year progression-free survival rate compared with PRAME low expression (20.0% vs. 88.9%, p = 0.043). The mean PRAME gene copy number relative to albumin (ALB) in normal samples was ∼1.0, whereas 4.0%, 24.0%, 70.0%, and 2.0% of patients had PRAME gene relative copy numbers of approximately 0, 0.5, 1.0, and 2.0, respectively. Patients with PRAME gene deletion (relative copy number of 0 or 0.5) had significantly higher frequency of PRAME nonoverexpression and lambda light chain expression than those with no deletion (p = 0.011 and 0.003). Thus, PRAME gene CNV occurs in MM. Gene deletion may be one mechanism leading to PRAME nonoverexpression and related to immunoglobulin lambda light chain locus rearrangement. PRAME overexpression in plasma cells might be an adverse prognostic factor for progression in MM.

PRAME overexpression predicted good outcome in pediatric B-cell acute lymphoblastic leukemia patients receiving chemotherapy

To investigate the prognostic value of PRAME expression in pediatric acute lymphoblastic leukemia(ALL), we measured PRAME transcript levels at diagnosis in 191 patients(146 B-ALL; 45T-ALL)receiving chemotherapy only. PRAME overexpression was defined as transcript levels higher than 0.30%, which is the upper limit of normal bone marrow and the optimal cutoff value derived from ROC curve analysis. PRAME overexpression was identified in 45.5% of patients. In B-ALL, PRAME overexpression was significantly associated with lower CIR(cumulative incidence of relapse), higher DFS (disease-freesurvival), and OS(overall survival) rates at 3 years, respectively (5.8% vs. 14.9%, P=0.014; 94.2% vs. 85.1%, P=0.014; 96.0% vs. 87.4%, P=0.039). PRAME overexpression had no impact on outcome in T-ALL patients. Among B-ALL patients with non-poor cytogenetic risk, those with PRAME overexpression showed significantly lower CIR, higher DFS and OS rates at 3 years, respectively (8.47% vs. 14.5%, P=0.009; 96.5% vs. 85.5%, P=0.009; 98.4% vs. 88.0%, P=0.023). Furthermore, PRAME overexpression was an independent good prognostic factor for relapse in all B-ALL patients and B-ALL patients with non-poor cytogenetic risk. Therefore, the prognostic significance of PRAME overexpression differed by ALL subtype; It predicted good outcome in pediatric B-ALL receiving chemotherapy.

A rapid, highly accurate method for quantifying CALR mutant allele burden in persons with myeloproliferative neoplasms

BACKGROUND

Calreticulin (CALR) mutations were recently identified in a substantial proportion of persons with essential thrombocythemia (ET) and with primary myelofibrosis (PMF) without JAK2(V617F). Consequently rapid, sensitive, and specific methods to detect and quantify these mutations are needed.

METHODS

We studied samples from 1088 persons with myeloproliferative neoplasms (MPNs) including 421 JAK2(V617F) negative subjects with ET, PMF, polycythemia vera (PV), chronic myeloid leukemia (CML) and hyper-eosinophilic syndrome (HES). Detection of CALR exon 9 mutations was done by PCR amplification followed by fragment length analysis and direct sequencing. Dilution assays were used to determine CALR mutant allele burden.

RESULTS

We detected CALR mutations in blood and bone marrow samples from 152 subjects with ET and with PMF but not in samples from normal or persons with PV, CML, or HES. CALR mutant peaks were distinct from wild-type peaks and dilution experiments indicated a sensitivity level of 0.5-5% for a CALR mutant allele in a wild-type background. Diverse types of mutations were detected including deletions, insertions, and complex indels. All mutations were confirmed by direct sequencing. We also used dilution experiments to quantify mutant allele burden. We were able to reproducibly detect mutant allele levels as low 5% (0.5-5%) in a wild-type background.

CONCLUSIONS

PCR amplification followed by fragment length analysis is a rapid, sensitive, and specific method for screening persons with MPNs for CALR mutations, especially those with ET and PMF and for estimating mutant allele burden.

Frequency and allele burden of CALR mutations in Chinese with essential thrombocythemia and primary myelofibrosis without JAK2(V617F) or MPL mutations

CALR mutations are detected in about 50% of persons of predominately European descent with essential thrombocythemia (ET) or primary myelofibrosis (PMF) with wild-type alleles of JAK2 and MPL. We studied 1088 Chinese with diverse myeloproliferative neoplasms including ET (N=234) and PMF (N=50) without JAK2(V617F) or MPL exon 10 mutations. CALR mutation was detected in 53% (95% CI, 46-60%) of subjects with ET and 56% (95% CI, 41-70%) of subjects with PMF. 152 CALR mutations were identified clustering into 15 types including deletions (N=8), insertions (N=3) and complex indels (N=4). We also identified 9 new mutations. Mean (±SD) mutant allele burden was 31±12% (range, 0.5-69%). Persons with PMF had higher CALR mutant allele burdens than those with ET (38±8% vs. 29±12%; P<0.001). Amongst persons with CALR mutations, those with PMF had different clinical features from those with ET. These data may be useful for diagnosing ET and PMF in Chinese who are about 40% of all persons with ET and PMF and for monitoring therapy-response. They also highlight similarities and differences in CALR mutations between Chinese and persons of predominately European descent with these diseases.

[Expression of WT1 and PRAME gene in bone marrow and peripheral blood samples of patients with myelodysplastic syndrome]

This study was aimed to explore the transcription level of WT1 and PRAME two genes in bone marrow and peripheral blood samples of patients with myelodysplastic syndrome(MDS) and their relationship with bone marrow dysplasia and karyotype. The quantitative expression of WT1 and PRAME transcripts detected by RQ-PCR in the bone marrow samples of 203 MDS patients and 19 aplastic anemia(AA), 6 other benign anemia(BA), 4 paroxysmal nocturnal hemoglobinuria(PNH) patients from July 2009 to June 2012 and 14 healthy donors, and in 92 peripheral blood samples. The results showed that WT1 and PRAME expression levels in both BM and PB samples of MDS group were higher than those in normal controls, AA, and BA patients (BM: WT1:P = 0.000, 0.000, 0.000, PRAME: P = 0.048, 0.000, 0.064; PB: WT1:P = 0.012, 0.000, 0.011, PRAME: P = 0.020, 0.004, 0.003). What is more, this expression in high risk MDS group (RAEB1, RAEB2, MDS-AML) were higher than those in low risk group (RCUD, RCMD, MDS-U) and AA and BA. The WT1 and PRAME mRNA expression levels in PB and BM were well correlated (WT1:r = 0.6028, P = 0.001; PRAME: r = 0.7628, P = 0.000), as well as the WT1 expression levels in BM samples with the Karyotype (P = 0.049). In addition, the same positive rate of WT1 or PRAME expression existed in BM and PB samples of MDS patients. It is concluded that the WT1 and PRAME gene expression levels in both BM and PB samples of MDS patients are higher than those in healthy controls, AA and other benign anemia patients, and increase with the progression of the disease. The WT1 and PRAME transcripts constitute good molecular markers for the clinical diagnosis and prognosis and monitoring minimal residual disease after treatment of MDS. What is more, when bone marrow is not so convenient to get, the transcript levels of PB samples can be detected.

[Applications of microchip electrophoresis and capillary electrophoresis for screening FLT3-ITD gene mutation in acute myeloid leukemia]

The purpose of the present study was to compare the reliability of microchip electrophoresis and capillary electrophoresis for screening FLT3-ITD gene mutation in acute myeloid leukemia. The FLT3-ITD mutation in the genomic DNA samples from 214 untreated AML patients were separately detected by PCR-microchip electrophoresis and PCR-capillary electrophoresis, then the DNA direct sequencing analysis was carried out. The results from PCR-microchip electrophoresis showed that there were 151 FLT3-ITD mutation negative, 58 FLT3-ITD mutation positive (58/214, 27.1%) and 5 FLT3-ITD mutation doubtful positive (5/214, 2.3%), while the outcomes from PCR-capillary electrophoresis displayed that there were 147 FLT3-ITD mutation negative and 67 FLT3-ITD mutation positive (67/214, 31.3%) without doubtful positive. In the 67 FLT3-ITD mutation positive samples detected by using PCR-capillary electrophoresis, 4 samples were detected as the negative while 5 samples were measured as the doubtful positive by using PCR-microchip electrophoresis. The followed sequencing analysis demonstrated that the above 9 samples were all FLT3-ITD mutation positive, indicating that PCR-capillary electrophoresis was more accurate and sensitive in screening the FLT3-ITD mutation, although statistic analysis showed that there were no significant differences in the detected results between PCR-microchip electrophoresis and PCR-capillary electrophoresis groups (Pearson Chi-squared Test, P > 0.05). It is concluded that both PCR-microchip electrophoresis and PCR-capillary electrophoresis were convenient and fast for screening FLT3-ITD mutation, but the accuracy of PCR-microchip electrophoresis awaits further improvement.

The clinical value of the quantitative detection of four cancer-testis antigen genes in multiple myeloma

BACKGROUND

Cancer-testis (CT) antigen genes might promote the progression of multiple myeloma (MM). CT antigens may act as diagnostic and prognostic markers in MM, but their expression levels and clinical implications in this disease are not fully understood. This study measured the expression levels of four CT antigen genes in Chinese patients with MM and explored their clinical implications.

METHODS

Real-time quantitative polymerase chain reaction (qPCR) was used to quantify the expression of MAGE-C1/CT7, MAGE-A3, MAGE-C2/CT10 and SSX-2 mRNA in 256 bone marrow samples from 144 MM patients.

RESULTS

In the newly diagnosed patients, the positive expression rates were 88.5% for MAGE-C1/CT7, 82.1% for MAGE-C2/CT10, 76.9% for MAGE-A3 and 25.6% for SSX-2. The expression levels and the number of co-expressed CT antigens correlated significantly with several clinical indicators, including the percentage of plasma cells infiltrating the bone marrow, abnormal chromosome karyotypes and the clinical course.

CONCLUSION

MAGE-C1/CT7, MAGE-A3, MAGE-C2/CT10 and SSX-2 expression levels provide potentially effective clinical indicators for the auxiliary diagnosis and monitoring of treatment efficacy in MM.

[Clinical significance of CD34(+)CD38(+) and CD34(+)CD38(low/-) subgroups in bone marrow of patients with B lymphoblastic leukemia]

This study was purpose to investigate the biological characteristics of B lymphoblastic leukemia (B-ALL) between CD34 positive CD38 positive (CD34(+)CD38(+)) and CD34(+)CD38(low/-) subgroups and their clinical significance. Immunophenotyping of B cells in bone marrow of 54 patients with newly diagnosed CD34(+)B-ALL were analyzed by 4 color multiparametric flow cytometry (FCM). According to the different expression of CD38, the newly diagnosed patients with B-ALL were divided into two groups: CD34(+)CD38(+) subgroup and CD34(+)CD38(low/-) subgroup. BCR-ABL, TEL-AML1 fusion genes and WT1 gene were detected by real time RT-PCR simultaneously. After chemotherapy, minimal residual disease (MRD) was monitored by one tube of 7 color FCM. The average follow-up time was 12 months (range 1 - 28), the average follow-up interval was 2 months (range 1 - 5). The results showed that there was no significant differences such as WBC, Plt count and Hb level between the two groups at diagnosis, the positive rate of BCR-ABL, TEL-AML1 and WT1 gene was also no significantly different. After clinical complete remission (CR), MRD positive (MDR(+)) case rates were 28.57% (10/35) in CD34(+)CD38(+) subgroup and 68.42% (13/19) in CD34(+)CD38(low/-) subgroup (P < 0.01). The relapse rate between the two groups was 5.71% (2/35) in CD34(+)CD38(+) subgroup (relapse time at 94 and 245 d respectively) and 36.84% (7/19) in CD34(+)CD38(low/-) group [median relapse time was 263 d (range 46 - 468), P < 0.01]. The age distribution was analyzed in these two subgroups (> 16 or ≤ 16 years old), there was 8 (8/35) adult patients (> 16 years old) in CD34(+)CD38(+)group and 10 (10/19) adult patients in CD34(+)CD38(low/-) group (P < 0.05). It is concluded that CD34(+)CD38(low/-) phenotype is more often presented in adult patients and the CD34(+)CD38(low/-) patients with B-ALL are more likely to have MRD(+)and relapse after treatment.

[Quantified research about the effects of sleep quality on attention in class and acadamic achievements in primary school children]

OBJECTIVE

To study the adverse effects of sleep problems and sleep insufficiency on attention in class and pupils' acadamic achievements.

METHODS

A total of 1138 students from four primary schools at ages of 6-12 years were randomly sampled from four districts of Changsha city, Hunan Province June 2009 to April 2010. The inquired items included sleep problems, sleep time, sleep quality, attention in class and academic achievements. Teachers and parents observed the pupils according to the unified requirements for 3 months and then filled out the questionnaires.

RESULTS

The total valid inquiry tables were 1091 with the answering rate of 95.87%, including 549 boys and 542 girls. The sleep quality was more poor in children with sleep problems or sleep insufficiency than in children with normal sleep. The sleep quality was reduced and aggravated along with the increasing sleep problems and the reducing sleep time. The attention in class and academic achievements in children with sleep problems or sleep insufficiency were more poor than in children with normal sleep. The sleep quality index was negatively correlated with attention in class and academic achievements. The attention in class was positively correlated with academic achievements.

CONCLUSIONS

The decline in sleep quality directly affects the attention in class and reduce the academic achievements in primary school children.

[Evaluating the feasibility of nucleated cells isolated by lysis method for real-time quantitative RT-PCR]

This study was aimed to investigate whether difference exists between real time RT-PCR results of nucleated cells isolated by lysis method and mononuclear cells isolated by gradient concentration method. 14 bone marrow samples from leukemia patients (7 samples of AML-M(2), 1 of AML-M(4), 1 of AML-M(4)EO, 1 of AML-M(6), 1 of APL and 3 of CML) were collected. Each sample was divided into 2 parts, and was used to isolate mononuclear cells by Ficoll-Hypaque gradient centrifugation, and other was used to isolate nuclear cells by lysis method. The RNA extraction and detection of internal reference gene ABL for all of samples were performed by RT-PCR, and mRNA expression levels in 3 samples of BCR/ABL, 6 of AML/ETO, 1 of CBFβ-MHY11, 1 of WT1 and 6 PRAME were detected by RT-PCR. The results showed that ABL copies of all samples were over 3 × 10(4), and there was significant difference in ABL copies between each pair of samples by lysis and gradient centrifugation method (p > 0.05). There was also no significant difference in every detected mRNA levels between 14 pair samples (p > 0.05). It is concluded that the lysis method may be useful one for extracting RNA from nuclear cells, and can adopt as a routing detection method for simultaneously extracting RNA from many samples to detect leukemia specific mRNA by using RT-PCR.

[Abnormal expression of programmed cell death 5 gene in multiple myeloma patients]

The aim of this study was to investigate the gene expression of programmed cell death 5 (pdcd5) in plasma and bone marrow cells from patients with multiple myeloma (MM). Enzyme liked immunosorbent assay (ELISA) and real-time quantitative reverse transcription polymerase chain reaction (RQ-RT-PCR) were used to examine pdcd5 gene expression in plasma and marrow cells in 45 MM patients and 20 normal controls. The results showed that serum levels of PDCD5 protein in 45 MM patients were lower significantly compared with the normal controls and 20 responsive patients after chemotherapy, their plasma levels were (16.91 +/- 0.28) ng/ml, (19.11 +/- 0.29) ng/ml and (17.94 +/- 0.154) ng/ml respectively (p < 0.05). The pdcd5 gene expression levels detected by RQ-RT-PCR in 45 MM patients were lower significantly compared with the normal controls, their pdcd5 gene expression levels were 0.64 +/- 0.47 and 1.28 +/- 1.21 respectively (p < 0.05). It is concluded that the PDCD5 protein expression levels are low in patients with MM. These findings suggest that abnormal expression of pdcd5 may be involved in the pathogenesis of MM.

[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.

[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.

[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.

[Analysis of immunophenotype and leukemia associated immunophenotype in 610 patients with acute myeloid leukemia]

OBJECTIVE

To analyze the immunophenotype and leukemia associated immunophenotype (LAIP) of leukemia cells from patients with acute myeloid leukemia (AML) in minimal residual disease (MRD) detection.

METHODS

Four-color multiparametric flow cytometry (FCM) with CD45/SSC gating was used to determine the expression of the following antibodies of CD7, CD117, CD33, CD34, CD10, CD19, CD56, CD38, CD13, CD14, CD64, CD9, CD16, CD2, CD5, CD11b, CD123, HLA-DR in 610 AML patients and 20 normal bone marrow (NBM) samples.

RESULTS

The mean percentages of CD34+ and CD117+ side scatter low (SSC(low)) cells in NBM mononuclear cells (BMMNCs) were (0.35 +/- 0.15)% and (0.76 +/- 0.31)%, respectively. The majority (84% -95%) of CD34+ SSC(low) cells co-expressed CD13, CD33, CD38, CD117 and HLA-DR. 33% and 20% of CD34+ SSC(low) cells were CD15+ and CD9, respectively. Only a small proportion (< 10%) of CD34 SSC(low) cell co-expressed CD11b, CD56, CD19 and CD64, while co-expressed CD7 was 12%. In CD117 SSC(low) cells, the relative proportions of CD19+, CD11b+, CD56+ and CD7+ were less than 10%, while CD9+ was 14%. CD38+ and HLA-DR+ were 87% and 91%, respectively. The expressions of CD15, CD34, CD13 and CD33 on CD117 SSC(low) cells were between 30% and 50%. In AML patients, most cases were CD117+ (95.08%), CD38+ (94.74%), CD9+ (84.93%), CD33+ (84.60%), HLA-DR+ (77.23%) and CD13 (75.25%). The proportions of CD64+ and CD34+ were 64.41% and 59.51%, and that of CD15 and CD11b+ were 43.06% and 22.07%, respectively. 86.39% of AML patients were found to have at least one LAIP, the highest incidence being in AML-M1 and M3 subtypes and the lowest in AML-M4Eo subtype. The cross-lineage antigen and asynchronous antigen expression were the most frequent aberrant phenotypes. CD7, CD19 and CD56 expressing on CD34+ cells were major cross-lineage antigen. For asynchronous antigen expression, CD34+ CD64+, CD117+ CD11b+ , CD34+ CD38(-/dim) and CD34+ HLA-DR(-/dim) were seldom expressed on normal BMMNCs (about 0.01%), and the logarithm difference between AML and NBM was larger than 3.0, being the more sensitive LAIP.

CONCLUSION

MRD detection by multiparameter flow cytometry can be applied to more than 80% of AML patients.

[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.

[Leukemia-associated immunophenotypes in 415 childhood and adult patients with B lineage acute lymphoblastic leukemia by multiparametric flow cytometry analysis]

To evaluate the significance of FCM in minimal residual disease (MRD) detection, the immunophenotyping and leukemia-associated immunophenotypes (LAIP) of leukemia cells from 273 adult and 142 childhood patients with B lineage acute lymphoblastic leukemia (B-ALL) were detected by four to six antibody combinations of 4-color CD45/SSC gating multiparametric flow cytometry (FCM). The results showed that the B-ALL patients could be classified into 4 subtypes based on different expression CD34 and CD10: subtype I (CD34(+)/CD10(-)), subtype II (CD34(+)/CD10(+)), subtype III (CD34(-)/CD10(+)), subtype IV (CD34(-)/CD10(-)). The LAIP was observed in 100% and 92% patients of subtype I and subtype II, respectively, whereas only 79.2% in subtype III. The incidence of LAIP in total B-ALL cases was 90% by using the antibodies detected in this investigation. There was no significantce different for incidence of LAIP between adult and pediatric patients. LAIP was observed in 77.6% of patients by labeling only CD34/CD10/CD19/CD45 4-color antibody combination. It is concluded that in 90% of childhood and adult B-ALL patients LAIP can be found, which suits MRD detection by multiparameter flow cytometry.

[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.

Estimation and projection of the national profile of cancer mortality in China: 1991-2005

There are no national-level data on cancer mortality in China since two surveys in 1973–1975 and 1990–1992 (a 10% sample), but ongoing surveillance systems, based on nonrandom selected populations, give an indication as to the trends for major cancers. Based on a log-linear regression model with Poisson errors, the annual rates of change for 10 cancers and all other cancers combined, by age, sex and urban/rural residence were estimated from the data of the surveillance system of the Center for Health Information and Statistics, covering about 10% of the national population. These rates of change were applied to the survey data of 1990–1992 to estimate national mortality in the year 2000, and to make projections for 2005. Mortality rates for all cancers combined, adjusted for age, are predicted to change little between 1991 and 2005 (−0.8% in men and +2.5% in women), but population growth and ageing will result in an increasing number of deaths, from 1.2 to 1.8 million. The largest predicted increases are for the numbers of female breast (+155.4%) and lung cancers (+112.1% in men, +153.5% in women). For these two sites, mortality rates will almost double. Cancer will make an increasing contribution to the burden of diseases in China in the 21st century. The marked increases in risk of cancers of the lung, female breast and large bowel indicate priorities for prevention and control. The increasing trends in young age groups for cancers of the cervix, lung and female breast suggest that their predicted increases may be underestimated, and that more attention should be paid to strategies for their prevention and control.

Estimation and projection of the national profile of cancer mortality in China: 1991-2005

There are no national-level data on cancer mortality in China since two surveys in 1973-1975 and 1990-1992 (a 10% sample), but ongoing surveillance systems, based on nonrandom selected populations, give an indication as to the trends for major cancers. Based on a log-linear regression model with Poisson errors, the annual rates of change for 10 cancers and all other cancers combined, by age, sex and urban/rural residence were estimated from the data of the surveillance system of the Center for Health Information and Statistics, covering about 10% of the national population. These rates of change were applied to the survey data of 1990-1992 to estimate national mortality in the year 2000, and to make projections for 2005. Mortality rates for all cancers combined, adjusted for age, are predicted to change little between 1991 and 2005 (-0.8% in men and +2.5% in women), but population growth and ageing will result in an increasing number of deaths, from 1.2 to 1.8 million. The largest predicted increases are for the numbers of female breast (+155.4%) and lung cancers (+112.1% in men, +153.5% in women). For these two sites, mortality rates will almost double. Cancer will make an increasing contribution to the burden of diseases in China in the 21st century. The marked increases in risk of cancers of the lung, female breast and large bowel indicate priorities for prevention and control. The increasing trends in young age groups for cancers of the cervix, lung and female breast suggest that their predicted increases may be underestimated, and that more attention should be paid to strategies for their prevention and control.

Solid-substrate room-temperature phosphorescence study on zinc(II) and tin(IV) protoporphyrins and their interaction with DNA

The solid-substrate room-temperature phosphorescence (SS-RTP) of two commercially available metalloporphyrin compounds, zinc(II) protoporphyrin (ZnPP) and tin(IV) protoporphyrin (SnPP) has been studied. Strong and stable RTP signals of the two metalloporphyrins in neutral to weakly basic solutions can be simply induced on filter paper without addition of external heavy atom perturbers. Their emission bands appeared at 723 nm for ZnPP and 718 nm for SnPP at an excitation wavelength of 417 nm. Compared with SnPP, ZnPP is a better RTP probe for DNA because its RTP enhancement effect is much higher under the same experimental conditions. The interaction of ZnPP with DNA at pH 8.5 gives an apparent binding constant of 9.1 x 10(3) which is similar to that of the cationic porphyrin absorption probe CuTMPyP (copper (II)- tetrakis(4-N-methylpyridyl)porphine complex). Hydrogen bonding between the monocarboxylic acid substituent of ZnPP and the base pairs of DNA plays a crucial role in the binding.

Determination of photophysical rate constants for the non-protected fluid room temperature phosphorescence of several naphthalene derivatives

The determination of kinetic parameters for luminescence processes is very important in understanding the phosphorescence process and the mechanisms of the heavy atom effect (HAE). In our previous work, we reported that room temperature phosphorescence (RTP) emission of many naphthalene derivatives can be induced directly from their aqueous solution without using any kind of protective medium, and the name Non-Protected Fluid Room Temperature Phosphorescence (NP-RTP) is suggested for this new type of RTP emission. In order to further understand this kind of luminescence phenomenon, the influence of heavy atom perturber (HAP) concentration on RTP lifetime of several naphthalene derivatives was studied in detail in this paper. The possibility of determination of photophysical parameters for emission of NP-RTP was explored based on the definition on the phosphorescence lifetime and the relation with the concentration of HAP in this paper. A static Stern-Volmer equation for phosphorescence was derived and the luminescence kinetic parameters were calculated. The results obtained by two different ways proved that photophysical parameters for RTP emission can be determined based on the changes of the RTP lifetime.

[The trends and preventive strategies of esophageal cancer in high-risk areas of Taihang Mountains, China]

OBJECTIVE

To analyze and predict the trends of incidence and mortality rates of esophageal cancer in areas of Taihang Mountains, and explore the strategies for facilitating the reduction of the incidence and mortality of esophageal cancer.

METHODS

The data were collected from Linxian and Cixian Counties registries between 1988-1997. The trends of the incidence and mortality rates for esophageal cancer had been fitted and predicted by the model of BP (Back Propagation) Neural Networks. Then Linqi Xiang in Linxian County was taken as an example, to determine the power for reducing incidence and mortality of esophageal cancer using endoscopic technology as an early detection and treatment method.

RESULTS

There were slowly declining trends for both incidence and mortality rates during past 10 years in Taihang Mountains. The predicting rates of the esophageal cancer incidence in 2,002 are 115. 70/100,000 for male and 79.88/100,000 for female; mortality rates are 94.00/100,000 and 56.29/100,000 respectively. Both incidence and mortality rates a still in high level. But when using endoscopic technology as an early detection and treatment method, the incidence rate is nearly 1/3 of a control group and the power is 88.30% at the end of eight years. The mortality rate is 1/4 of the control group and power is 89.44% after five years intervention (both powers based on 0.05 significant levels).

CONCLUSIONS

The incidence and mortality rates for esophageal cancer are still on high levels in Taihang Mountains. We should continue to enhance our preventive effort there. After using endoscopic technology as an early detection and treatment method, the incidence and mortality rates will be decreased markedly during 5 to 8 years. It is recommended to implement a large-scale secondary prevention strategy in these areas.

Adoptive transfer of murine autoimmune orchitis with sperm-specific T lymphoblasts

A protocol was successfully developed for reproducibly transferring experimental autoimmune orchitis (EAO) to naive recipient mice with sperm-specific T lymphoblasts. Cell donors were Balb/c mice immunized about 12 days earlier with homologous epididymal sperm capacitated in vitro with complete Freund's adjuvant. Draining lymph node cells were collected and subjected to a second challenge with the same sperm antigen in vitro. Sperm-specific T lymphoblasts were isolated on Percoll density gradients and propagated in the presence of interleukin-2 for 3 days and then were transferred intraperitoneally to naive recipients. As few as 3 x 10(6) sperm-specific T lymphoblasts were able to transfer EAO, which began on day 7 as infiltration of lymphocytes and macrophages and on days 14 to 21 developed to degenerative changes of spermatids and exfoliation of germinal epithelium. These pathologic alterations resemble a delayed type of hypersensitivity. The results show that sensitized T lymphoblasts can mediate an antigen-specific, mononuclear cell-invasive lesion in autoimmune orchitis.