DPEP1 expression promotes proliferation and survival of leukaemia cells and correlates with relapse in adults with common B cell acute lymphoblastic leukaemia.

Dehydropeptidase-1 (DPEP1) is a zinc-dependent metalloproteinase abnormally expressed in many cancers. However, its potential role in adults with B cell acute lymphoblastic leukaemia (ALL) is unknown. We found that in adults with common B cell ALL high DPEP1, transcript levels at diagnosis were independently associated with an increased cumulative incidence of relapse (CIR) and worse relapse-free survival (RFS) compared with subjects with low transcript levels. We show an increased proliferation and prosurvival role of DPEP1 in B cell ALL cells via regulation of phosphCREB and p53, which may be the biological basis of the clinical correlation we report. Our data implicate DPEP1 expression in the biology of common B cell ALL in adults. We report clinical correlates and provide a potential biological basis for these correlations. If confirmed, analysing DPEP1 transcript levels at diagnosis could help predict therapy outcomes. Moreover, regulation of DPEP1 expression could be a therapy target in B cell ALL.

Mutation topography and risk stratification for de novo acute myeloid leukaemia with normal cytogenetics and no nucleophosmin 1 (NPM1) mutation or Fms-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD).

About 25% of patients with newly diagnosed acute myeloid leukaemia (AML) have normal cytogenetics and no nucleophosmin 1 (NPM1) mutation or Fms-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD). The prognosis and best therapy for these patients is controversial. We evaluated 158 newly diagnosed adults with this genotype who achieved histological complete remission within two cycles of induction therapy and were assigned to two post-remission strategies with and without an allotransplant. Targeted regional sequencing at diagnosis was performed and data were used to estimate their prognosis, including relapse and survival. In multivariable analyses, having wild-type or mono-allelic mutated CCAAT/enhancer-binding protein alpha (CEBPA) [hazard ratio (HR) 2·39, 95% confidence interval (CI) 1·08-5·30; P = 0·032), mutated NRAS (HR 2·67, 95% CI 1·36-5·25; P = 0·004), mutated colony-stimulating factor 3 receptor (CSF3R) (HR 2·85, 95% CI 1·12-7·27; P = 0·028) and a positive measurable residual disease (MRD)-test after the second consolidation cycle (HR 2·88, 95% CI 1·32-6·30; P = 0·008) were independently correlated with higher cumulative incidence of relapse (CIR). These variables were also significantly associated with worse survival (HR 3·02, 95% CI 1·17-7·78, P = 0·022; HR 3·62, 95% CI 1·51-8·68, P = 0·004; HR 3·14, 95% CI 1·06-9·31, P = 0·039; HR 4·03, 95% CI 1·64-9·89, P = 0·002; respectively). Patients with ≥1 of these adverse-risk variables benefitted from a transplant, whereas the others did not. In conclusion, we identified variables associated with CIR and survival in patients with AML and normal cytogenetics without a NPM1 mutation or FLT3-ITD.

Overexpressed WT1 exhibits a specific immunophenotype in intermediate and poor cytogenetic risk acute myeloid leukemia.

Many studies have confirmed that overexpressed WT1 exists in leukemic cells, especially in AML. However, the immunophenotypic features of this sort of leukemic cells remain to be unclarified. We retrospectively analyzed the immunophenotype of 283 newly diagnosed AML patients with intermediated and poor cytogenetic risk to evaluate the correlation between phenotype and WT1 overexpression. EVI1 transcripts, KMT2A-PTD, FLT3-ITD, and NPM1 mutations were simultaneously assessed. Our results revealed that overexpressed WT1 was significantly associated with the expression of CD117, CD13, and CD123. Besides, leukemic cells with WT1 overexpression also lacked lymphoid and myeloid differentiation-related markers. FAB subtype M2 patients had higher WT1 levels, compared with other FAB subtype. Multivariate analysis was proved that NPM1 mutation, M2 subtype, and the expression of CD123 were independently associated with WT1 overexpression. These indicated that AML with overexpressed WT1 was proliferated and blocked in the early stage of AML development. It presumably provided some clues to detect overexpressed WT1 cells via multiparameter flow cytometry. CD123-targeted drugs might become one of the alternative treatments for patients with WT1 overexpression.

The predictive value of minimal residual disease when facing the inconsistent results detected by real-time quantitative PCR and flow cytometry in NPM1-mutated acute myeloid leukemia.

For acute myeloid leukemia (AML) with nucleophosmin 1 mutation (NPM1m), multiparameter flow cytometry (FCM) and real-time quantitative polymerase chain reaction (RQ-PCR) are used to monitor minimal residual disease (MRD). However, the results of the two methods are sometimes inconsistent. This study was designed to analyze how to address the discordant results of FCM and RQ-PCR in AML patients undergoing chemotherapy, especially when positive FCM (FCM+) and negative NPM1m (NPM1m-) results are detected in the same sample. Our study included 93 AML patients with NPM1m positive (NPM1m+) who received chemotherapy but did not undergo hematopoietic stem cell transplantation. We monitored NPM1m and leukemia-associated immunophenotypes (LAIPs) by RQ-PCR and FCM, respectively, to assess MRD after each chemotherapy course. After each course of chemotherapy, all patients were classified into four groups based on the results of FCM and RQ-PCR: both negative (group 1, FCM-NPM1m-), single positive (group 2, FCM-NPM1m+; group 3, FCM+NPM1m-), or both positive (group 4, FCM+NPM1m+). The results showed that there was not a significant difference in the 2-year cumulative incidence of relapse (CIR) after each course of chemotherapy between group 2 and group 3. Furthermore, patients in groups 2 and 3 had a lower 2-year CIR than those in group 4 and a significantly higher 2-year CIR than those in group 1 after the first two courses. The patients in group 4 had a significantly higher 2-year CIR than those in group 1 after the first two courses. These results suggested that in the MRD monitoring process of AML patients, when the results of FCM and RQ-PCR are inconsistent (especially when FCM is positive and NPM1m is negative), these single-positive results still have predictive significance for relapse.

Osteoclast stimulatory transmembrane protein (OC-STAMP) is a promising molecular prognostic indicator for multiple myeloma.

BACKGROUND: Currently, the prognostic stratification and therapeutic evaluation systems for multiple myeloma (MM) lack specific molecular indicators. OC-STAMP is a new gene and is also highly expressed in MM. METHODS: A total of 160 MM patients have been investigated with both quantitative reverse transcription PCR (RT-qPCR), flow cytometry (FCM) and cytogenetic FISH on the same mononuclear cells isolated from bone marrow specimens. RESULTS: We found that OC-STAMP mRNA levels were significantly higher in newly diagnosed cases of MM than in healthy donors (median, 0.52% vs. 0.02%, P < .001). Moreover, the changes in the OC-STAMP mRNA levels paralleled the disease stages and minimal residual disease, as detected by FCM. Furthermore, we found that patients with high OC-STAMP mRNA levels were more likely to develop ≥3 bone lesions, be diagnosed with Durie-Salmon stages III, and have the P53 (17p13) deletion. In addition, advanced stage patients with high OC-STAMP mRNA levels had a lower 4-year progression-free survival (5.6% vs. 22.9%, P = .0055) and a worse 4-year overall survival (25.8% vs. 48.8%, P = .0137) compared to patients with low mRNA levels of this indicator. CONCLUSIONS: OC-STAMP may be a promising molecular indicator to monitor treatment effects and participate in the prognostic stratification of MM.

MAGE genes: Prognostic indicators in AL amyloidosis patients.

A high frequency of MAGE-CT (cancer testis) antigens are expressed in Multiple Myeloma (MM) patients; however, in other plasma cell dyscrasias, their potential function remains unclear. We measured the expression of MAGE-CT genes (MAGE-C1/CT7, MAGE-A3, MAGE-C2/CT10) in 105 newly diagnosed amyloid light-chain (AL) amyloidosis patients between June 2013 and January 2018 at Peking University People's Hospital using real-time quantitative polymerase chain reaction. In the newly diagnosed AL patients, the positive expression rates of patients with MAGE-C1/CT7, MAGE-C2/CT10 and MAGE-A3 were 83.8% (88/105), 56.71% (38/67) and 22.0% (13/59) respectively. There was no significant correlation between organ propensity and MAGE-CT gene expression. Changes in the MAGE-C1/CT7 levels were consistent with a therapeutic effect. The expression levels of MAGE-C1/CT7, MAGE-C2/CT10 and MAGE-A3 provide potentially effective clinical indicators for auxiliary diagnoses and monitoring treatment efficacy in AL amyloidosis patients.

S100A16 suppresses the growth and survival of leukaemia cells and correlates with relapse and relapse free survival in adults with Philadelphia chromosome-negative B-cell acute lymphoblastic leukaemia.

Refinement of risk stratification in Philadelphia chromosome (Ph)-negative B-cell acute lymphoblastic leukaemia (ALL) might aid the identification of patients who are likely to relapse. Abnormal S100 calcium binding protein A16 (S100A16) has been implicated in various cancers, but its function remains unclear. We found S100A16 transcript levels were higher in 130 adults with newly-diagnosed Ph-negative B-cell ALL compared with 33 healthy controls. In 115 of 130 patients who achieved first complete remission, those with high S100A16 transcript levels displayed a lower 3-year cumulative incidence of relapse (CIR; 34% [21, 47%] vs. 40% [48, 72%]; P = 0·012) and higher 3-year relapse-free survival (RFS; 65% [53, 78%] vs. 35% [23, 46%]; P = 0·012), especially when receiving chemotherapy only. In multivariate analysis a low S100A16 transcript level was independently-associated with a higher CIR (Hazard ratio [HR] = 3·74 [1·01-13·82]; P = 0·048) and inferior RFS (HR = 5·78 [1·91, 17·84]; P < 0·001). Function analysis indicated that knockdown of S100A16 promoted proliferation and anti-apoptosis and reduced chemosensitivity. S100A16 over-expression revealed an opposite trend, especially in a xeno-transplant mouse model. Western blotting analysis showed upregulation of PI3K/AKT and ERK1/2 in S100A16-knockdown and S100A16-overexpression B-cell ALL cell lines respectively. Inhibition assays suggested these two signalling pathways participated in the S100A16-mediated proliferation and survival effects in B-cell ALL cell lines. Trial Registration: Registered in the Chinese Clinical Trial Registry [ChiCTR-OCH-10000940]; http://www.chictr.org.cn.

Allogeneic Stem Cell Transplantation versus Tyrosine Kinase Inhibitors Combined with Chemotherapy in Patients with Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia.

Here we compare outcomes between the tyrosine kinase inhibitors (TKIs) plus chemotherapy regimen and allogeneic hematopoietic stem cell transplantation (transplantation cohort) in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) and explore factors associated with prognosis. Data from 145 Ph+ ALL patients were analyzed retrospectively. Patients were treated with imatinib plus chemotherapy and then transplantation or continuous TKIs with chemotherapy based on patient preference. A total of 145 Ph+ ALL patients were recruited for this study (median age, 37 years; range, 14 to 65). Among these patients, 81 were men (55.9%) and 86 underwent IKZF1 detection, which identified 59 patients (68.6%) with IKZF1 deletions. After treatment 136 patients (95.8%) achieved complete remission (CR) eventually. With a median follow-up of 33 months (range, 4 to 114) for CR patients, 77 patients (57.9%) underwent transplantation and 56 (42.1%) received continuous TKIs with chemotherapy. At the 4-year follow-up the cumulative incidence of relapse (CIR), disease-free survival (DFS), and overall survival (OS) were 29.4% (95% confidence interval [CI], 24.9% to 34.4%), 60.9% (95% CI, 56.5% to 65.3%), and 69.2% (95% CI, 65.1% to 73.3%), respectively. Multivariate analysis showed that WBC counts < 30 × 109/L at diagnosis (hazard ratio [HR], 4.2; 95% CI, 1.9 to 9.2; P < .001; HR, 2.6; 95% CI, 1.4 to 4.9; P = .003; HR, 2.7; 95% CI, 1.4 to 5.4; P = .003), 3-log reduction of BCR-ABL levels from baseline after 2 consolidation cycles (HR, 4.4; 95% CI, 1.9 to 9.9; P < .001; HR, 3.1; 95% CI, 1.7 to 5.9; P < .001; HR, 3.5; 95% CI, 1.9 to 8.7; P = .001; defined as "minimal residual disease low level"), and transplantation (HR, 5.0; 95% CI, 2.2 to 11.2; P < .001; HR, 3.3; 95% CI, 1.7 to 6.4; P < .001; HR, 4.1; 95% CI, 1.9 to 8.7; P < .001) were the favorable factors of CIR, DFS, and OS. According to the first 2 risk factors, CR patients were divided into 3 groups: low risk (no factor, n = 42, 31.6%), intermediate risk (1 factor, n = 73, 54.9%), and high risk (2 factors, n = 18, 13.5%). In the low-risk group at the 4-year follow up no significant difference existed between the transplant and nontransplant arms for the probabilities of CIR (8.5% versus 7.7%, P = .671), DFS (88.2% versus 83.9%, P = .426), and OS (96.6% versus 83.3%, P = .128). In the intermediate- and high-risk groups at the 4-year follow-up, CIR (23.6% versus 36.9%, P = .017; 37.5% versus 100.0%, P <.001), DFS (62.4% versus 43.8%, P = .048; 56.2% versus 0%, P <.001), and OS (76.1% versus 47.7%, P = .037; 51.4% versus 6.3%, P = .001) rates were significantly better in the transplant arm than in the nontransplant arm. In surviving patients of the low-risk group, no difference in complete molecular response (CMR) rates (85.7% versus 72.7%, P = .379) between the transplant and nontransplant arms was found. However, in the intermediate-risk group the proportion of CMR was significantly higher in the transplant arm than in the nontransplant arm (82.8% versus 42.9%, P = .006). In the high-risk group 4 of 7 transplant patients (57.1%) were in CMR, and no patients survived in the nontransplant arm. Allogeneic hematopoietic stem cell transplantation confers significant survival advantages for Ph+ ALL patients compared with TKIs plus chemotherapy, especially in intermediate- and high-risk patients.

Synergistic antitumor activity of triple-regulated oncolytic adenovirus with VSTM1 and daunorubicin in leukemic cells.

V-set and transmembrane domain-containing 1 (VSTM1), which is downregulated in bone marrow cells from leukemia patients, may provide a diagnostic and treatment target. Here, a triple-regulated oncolytic adenovirus was constructed to carry a VSTM1 gene expression cassette, SG611-VSTM1, and contained the E1a gene with a 24-nucleotide deletion within the CR2 region under control of the human telomerase reverse transcriptase promoter, E1b gene directed by the hypoxia response element, and VSTM1 gene controlled by the cytomegalovirus promoter. Real-time quantitative PCR and Western blot analyses showed that SG611-VSTM1 expressed VSTM1 highly efficiently in the human leukemic cell line K562 compared with SG611. In Cell Counting Kit-8 and flow cytometric assays, SG611-VSTM1 exhibited more potent anti-proliferative and pro-apoptotic effects in leukemic cells compared with SG611 and exerted synergistic cytotoxicity with low-dose daunorubicin (DNR) in vitro. In xenograft models, SG611-VSTM1 intratumorally injected at a dose of 1 × 10(9) plaque forming units combined with intraperitoneally injected low-dose DNR displayed significantly stronger antitumor effects than either treatment alone. Histopathologic examination revealed that SG611-VSTM1 induced apoptosis of leukemic cells. These results implicate an important role for VSTM1 in the pathogenesis of leukemia, and SG611-VSTM1 may be a promising agent for enhancing chemosensitivity in leukemia therapy.

Prognostic impact of IKZF1 deletion in adults with common B-cell acute lymphoblastic leukemia.

BACKGROUND: Interrogate the impact of IKZF1 deletion on therapy-outcomes of adults with common B-cell acute lymphoblastic leukemia. METHODS: One hundred sixty-five consecutive adults with common B-cell ALL were tested for IKZF1 deletion and for BCR/ABL. Deletions in IKZF1 were detected using multiplex RQ-PCR, multiplex fluorescent PCR, sequence analysis and multiplex ligation-dependent probe amplification (MLPA). BCR/ABL was detected using RQ-PCR. All subjects received chemotherapy and some also received an allotransplant and tyrosine kinase-inhibitors. Multivariate analyses were done to identify associations between IKZF1 deletion and other variables on non-relapse mortality (NRM), cumulative incidence of relapse (CIR), leukemia-free survival (LFS) and survival. RESULTS: Amongst subjects achieving complete remission those with IKZF1 deletion had similar 5-year non-relapse mortality (NRM) (11% [2-20%] vs. 16% [4-28%]; P = 0.736), a higher 5-year cumulative incidence of relapse (CIR) (55% [35-76%] vs. 25% [12-38%]; P = 0.004), and worse 5-year leukemia-free survival (LFS) (33% [16-52%] vs. 59% [42-73%]; P = 0.012) and survival (48% [33-62%] vs. 75% [57-86%]; P = 0.002). In multivariate analyses IKZF1 deletion was associated with an increased relapse (relative risk [RR] =2.7, [1.4-5.2]; P = 0.002), a higher risk of treatment-failure (inverse of LFS; RR = 2.1, [1.2-3.6]; P = 0.007) and a higher risk of death (RR = 2.8, [1.5-5.5]; P = 0.002). The adverse impact of IKZF1 deletion on outcomes was stronger in subjects without vs. with BCR-ABL1 and in subjects receiving chemotherapy-only vs. an allotransplant. CONCLUSIONS: IKZF1 deletion was independently-associated with a higher relapse risk and worse LFS and survival in adults with common B-cell ALL after adjusting for other prognostic variables and differences in therapies. These data suggest IKZF1 deletion may be a useful prognostic variable in adults with common B-cell ALL, especially in persons without BCR-ABL1 and those receiving chemotherapy-only. Transplants appear to overcome the adverse impact of IKZF1 deletion on therapy-outcomes but confirmation in a randomized study is needed. The trial was registered in 2007 with the Beijing Municipal Government (Beijing Municipal Health Bureau Registration N: 2007-1007).

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.

Extracellular matrix protein 1 (ECM1) is a potential biomarker in B cell acute lymphoblastic leukemia.

B cell acute lymphoblastic leukemia (ALL) is characterized by the highly heterogeneity of pathogenic genetic background, and there are still approximately 30-40% of patients without clear molecular markers. To identify the dysregulated genes in B cell ALL, we screened 30 newly diagnosed B cell ALL patients and 10 donors by gene expression profiling chip. We found that ECM1 transcription level was abnormally elevated in newly diagnosed B cell ALL and further verified in another 267 cases compared with donors (median, 124.57% vs. 7.14%, P < 0.001). ROC analysis showed that the area under the curve of ECM1 transcription level at diagnosis was 0.89 (P < 0.001). Patients with BCR::ABL1 and IKZF1 deletion show highest transcription level (210.78%) compared with KMT2A rearrangement (39.48%) and TCF3::PBX1 rearrangement ones (30.02%) (all P < 0.05). Also, the transcription level of ECM1 was highly correlated with the clinical course, as 20 consecutive follow-up cases indicated. The 5-year OS of patients (non-KMT2A and non-TCF3::PBX1 rearrangement) with high ECM1 transcription level was significantly worse than the lower ones (18.7% vs. 72.9%, P < 0.001) and high ECM1 transcription level was an independent risk factor for OS (HR = 5.77 [1.75-19.06], P = 0.004). After considering transplantation, high ECM1 transcription level was not an independent risk factor, although OS was still poor (low vs. high, 71.1% vs. 56.8%, P = 0.038). Our findings suggested that ECM1 may be a potential molecular marker for diagnosis, minimal residual disease (MRD) monitoring, and prognosis prediction of B cell ALL.Trial registration Trial Registration Registered in the Beijing Municipal Health Bureau Registration N 2007-1007 and in the Chinese Clinical Trial Registry [ChiCTR-OCH-10000940 and ChiCTR-OPC-14005546]; http://www.chictr.org.cn .

Measurable residual disease testing by next generation sequencing is more accurate compared with multiparameter flow cytometry in adults with B-cell acute lymphoblastic leukemia.

Results of measurable residual disease (MRD)-testing by next-generation sequencing (NGS) correlate with relapse risk in adults with B-cell acute lymphoblastic leukemia (ALL) receiving chemotherapy or an allotransplant from a human leukocyte antigen (HLA)-identical relative or HLA-matched unrelated donor. We studied cumulative incidence of relapse (CIR) and survival prediction accuracy using a NGS-based MRD-assay targeting immunoglobulin genes after 2 courses of consolidation chemotherapy cycles in 93 adults with B-cell ALL most receiving HLA-haplotype-matched related transplants. Prediction accuracy was compared with MRD-testing using multi-parameter flow cytometry (MPFC). NGS-based MRD-testing detected residual leukemia in 28 of 65 subjects with a negative MPFC-based MRD-test. In Cox regression multi-variable analyses subjects with a positive NGS-based MRD-test had a higher 3-year CIR (Hazard Ratio [HR] = 3.37; 95 % Confidence Interval [CI], 1.34-8.5; P = 0.01) and worse survival (HR = 4.87 [1.53-15.53]; P = 0.007). Some data suggest a lower CIR and better survival in NGS-MRD-test-positive transplant recipients but allocation to transplant was not random. Our data indicate MRD-testing by NGS is more accurate compared with testing by MPFC in adults with B-cell ALL in predicting CIR and survival. (Registered in the Beijing Municipal Health Bureau Registration N 2007-1007 and in the Chinese Clinical Trial Registry [ChiCTR-OCH-10000940 and ChiCTROPC-14005546]).

CSRP2 transcript levels after consolidation therapy increase prognostic prediction ability in B-cell acute lymphoblastic leukaemia.

Quantification of measurable residual disease (MRD) correlates with the risk of leukemia recurrence in adults with B-cell acute lymphoblastic leukemia (ALL). However, it remains unknown whether collecting data on cysteine and glycine-rich protein 2 (CSRP2) transcript levels, after completing the second course of consolidation, improves prognosis prediction accuracy. A total of 204 subjects with B-cell ALL were tested for CSPR2 transcripts after completing the second course of consolidation using quantitative real-time polymerase chain reaction (qRT-PCR) and divided into high (N = 32) and low (N = 172) CSRP2 expression cohorts. In multivariable analyses, subjects with high expression of CSRP2 had a higher 5-year cumulative incidence of relapse (CIR) (hazard ratio [HR] = 2.57, 95% confidence interval [CI] 1.38-4.76; P = 0.003), lower 5-year relapse-free survival (RFS) (HR = 3.22, 95% CI 1.75-5.93; P < 0.001), and overall survival (OS) (HR = 4.59, 95% CI 2.64-7.99; P < 0.001) in the whole cohort, as well as in the multi-parameter flow cytometry (MPFC) MRD-negative cohort (for CIR, HR = 2.70, 95% CI 1.19-6.12; for RFS, HR = 4.37, 95% CI 1.94-9.85; for OS, HR = 4.90, 95% CI 2.43-9.90; all P < 0.05). Prognostic analysis showed that allogeneic hematopoietic stem cell transplantation (allo-HSCT) could significantly improve the prognosis of patients with high CSRP2 expression (allo-HSCT vs chemotherapy: 5-year CIR, 52% vs 91%; RFS, 41% vs 9%; OS, 38% vs 20%; all P < 0.05). Our data indicate that incorporating data from CSPR2 transcript levels to the MRD-testing at the end of the second course of consolidation therapy enhances prognosis prediction accuracy in adults with B-cell ALL.

Prognostic value of RASD1 transcript levels in adult Philadelphia-negative B-cell acute lymphoblastic leukemia.

OBJECTIVES: Ras-related dexamethasone-induced 1 (RASD1) is abnormally expressed in many solid cancers. However, its potential role in adults with B-cell acute lymphoblastic leukemia (B-ALL) is unclear. Therefore, we aim to clarify the abnormal expression of the tumor-associated biomarker, RASD1, as a potential target for diagnosis and prognosis in adult Philadelphia-negative B-ALL. METHODS: The expression of RASD1 was detected with RT-qPCR in 92 adults with de novo Ph-negative B-ALL and 40 healthy controls. The correlation between RASD1 transcript levels and relapse was assessed. RESULTS: RASD1 transcript levels in patients with Ph-negative B-ALL (median 81.76%, range 0.22%-1824.52%) were significantly higher than those in healthy controls (7.59%, 0.46%-38.66%; P<0.0001). Patients with low RASD1 transcript levels had a lower 5-year relapse-free survival (RFS, 47.5% [32.9%, 62.1%] vs. 63.1% [49.0%, 77.2%]; P = 0.012) and a higher 5-year cumulative incidence of relapse (CIR, 52.0% [37.4%, 66.6%] vs. 36.2% [22.2%, 50.2%]; P = 0.013) especially in patients receiving chemotherapy only. Multivariate analysis showed that a low RASD1 transcript level was an independent risk factor for RFS (HR = 2.938 [1.427, 6.047], P = 0.003) and CIR (HR = 3.367 [1.668, 6.796], P = 0.001) in patients with Ph-negative B-ALL. CONCLUSIONS: RASD1 transcript levels were significantly higher in patients with Ph-negative B-ALL and a low RASD1 transcript level was independently correlated with increased relapse risk.

Interferon-α as maintenance therapy can significantly reduce relapse in patients with favorable-risk acute myeloid leukemia.

To evaluate the efficacy of interferon-α (IFN-α) as maintenance therapy in patients with favorable-risk acute myeloid leukemia (AML), this retrospective study enrolled 84 patients with favorable-risk AML: 42 patients who received IFN-α maintenance therapy and 42 patients who did not (control). The median follow-up time and duration of IFN-α treatment was 26 (6-54) months and 18 (2-24) months, respectively. The 4-year estimated relapse-free survival (RFS) after the last consolidation chemotherapy was 86.8% (95% confidence interval (CI), 75.8-97.8%) in the IFN-α group and 55.7% (95% CI, 37.2-74.3%) in the control group (p=.007). The 4-year estimated overall survival was 94.4% (95% CI, 86.8-102%) and 76.4% (95% CI, 61.9-90.9%) in IFN-α and control groups, respectively (p=.040). The Cox regression analysis showed that IFN-α treatment was the only independent factor affecting RFS (p=.004). Maintenance therapy with IFN-α may prevent relapse in favorable-risk AML after consolidation chemotherapy.

Risk Stratification of Cytogenetically Normal Acute Myeloid Leukemia With Biallelic CEBPA Mutations Based on a Multi-Gene Panel and Nomogram Model.

BACKGROUND: Approximately 30% of Chinese individuals with cytogenetically normal acute myeloid leukemia (CN-AML) have biallelic CEBPA (biCEBPA) mutations. The prognosis and optimal therapy for these patients are controversial in clinical practice. METHODS: In this study, we performed targeted region sequencing of 236 genes in 158 individuals with this genotype and constructed a nomogram model based on leukemia-free survival (LFS). Patients were randomly assigned to a training cohort (N =111) and a validation cohort (N =47) at a ratio of 7:3. Risk stratification was performed by the prognostic factors to investigate the risk-adapted post-remission therapy by Kaplan-Meier method. RESULTS: At least 1 mutated gene other than CEBPA was identified in patients and mutation number was associated with LFS (61.6% vs. 39.0%, P =0.033), survival (85.6% vs. 62.9%, P =0.030) and cumulative incidence of relapse (CIR) (38.4% vs. 59.5%, P =0.0496). White blood cell count, mutations in CFS3R, KMT2A and DNA methylation related genes were weighted to construct a nomogram model and differentiate two risk subgroups. Regarding LFS, low-risk patients were superior to the high-risk (89.3% vs. 33.8%, P <0.001 in training cohort; 87.5% vs. 18.2%, P =0.009 in validation cohort). Compared with chemotherapy, allogenic hematopoietic stem cell transplantation (allo-HSCT) improved 5-year LFS (89.6% vs. 32.6%, P <0.001), survival (96.9% vs. 63.6%, P =0.001) and CIR (7.2% vs. 65.8%, P <0.001) in high-risk patients but not low-risk patients (LFS, 77.4% vs. 88.9%, P =0.424; survival, 83.9% vs. 95.5%, P =0.173; CIR, 11.7% vs. 11.1%, P =0.901). CONCLUSIONS: Our study indicated that biCEBPA mutant-positive CN-AML patients could be further classified into two risk subgroups by four factors and allo-HSCT should be recommended for high-risk patients as post-remission therapy. These data will help physicians refine treatment decision-making in biCEBPA mutant-positive CN-AML patients.

MPL W515L/K mutations in 343 Chinese adults with JAK2V617F mutation-negative chronic myeloproliferative disorders detected by a newly developed RQ-PCR based on TaqMan MGB probes.

Acquired mutations in the juxtamembrane region of MPL (W515L or W515K), the receptor for thrombopoietin, have been reported in patients with primary essential thrombocythemia (ET) or primary myelofibrosis (PMF). The mutations were detected by the newly developed real-time quantitative PCR (RQ-PCR) with TaqMan MGB probes and followed by the sequencing analysis. DNA samples were from 343 Chinese adults with JAK2V617F mutation-negative chronic myeloproliferative disorders (cMPDs). Reference curves were obtained using cloned fragments of MPL containing either the wild-type or MPL W515L or MPL W515K mutated sequence; the predicted sensitivity level was at least 0.5%(0.1-0.5%) for MPL W515L and 0.5%(0.2-0.5%) for MPL W515K mutant allele in a wild-type background. The detection rates of MPL W515 mutations were 3.5% in 199 ET patients (7/199), 12.5% in 24 PMF patients (3/24) and 5.6% in 36 cMPD-unclassed patients (2/36), respectively. No MPL W515 mutations were detected in 32 polycythemia vera (PV) patients, 40 chronic myeloid leukaemia (CML) patients, 12 hypereosinophilic syndrome (HES) patients and 29 normal volunteers. The mean calculated burden of MPL mutant alleles using RQ-PCR for MPL W515L/K was 24.88 +/- 14.80% (range, 1.10-56.32%). MPL W515L/K patients presented lower haemoglobin levels, compared with the patients with JAK2V617F mutation-positive cMPDs (p < 0.01). The results demonstrated that RQ-PCR was a reliable and sensitive method for large-scale screening of the MPL W515L/K mutation in patients suspected to have a cMPD. It can also provide a quantitative estimate of mutant allele burden that might be useful for both patient prognosis and monitoring response to therapy.

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.