MicroRNAs are important regulators of the pathogenesis of B-cell acute lymphoblastic leukaemia (B-ALL). In this study, we identified miR-3173 and its predicted target gene PTK2 were correspondingly ...differentially expressed in B-ALL patients. In B-ALL cell lines, CCK-8 proliferation assay revealed that miR-3173 could inhibit the cell proliferation. Moreover, transwell assay revealed that miR-3173 could also inhibit cell migration and invasion in B-ALL cell lines. Luciferase assays revealed that miR-3173 directly bound to the 3′untranslated region of PTK2, and western blotting showed that miR-3173 suppressed the expression of PTK2 at the protein level. Generally, this study indicates that miR-3173 negatively regulates PTK2 and inhibits proliferation and invasion of B-ALL cell lines. Thus, miR-3173 may represent a potential therapeutic molecule for B-ALL intervention.
•miR-3173 is down-regulated in B-ALL patients.•miR-3173 inhibits the proliferation and invasion of B-ALL cells.•miR-3173 targets the 3′ UTR of PTK2 in B-ALL cells.•miR-3173 inhibits PTK2 in B-ALL cells.
Long non-coding RNAs (lncRNAs) represent a diverse class of RNAs involved in the regulation of various physiological and pathological cellular processes, including transcription, intracellular ...trafficking, and chromosome remodeling. LncRNAs deregulation was linked to the development and progression of various cancer types, such as acute leukemias. In this context, lncRNAs were also evaluated as a novel class of biomarkers for cancer diagnosis and prognosis. Here, we analyzed TEX41 in childhood B cell acute lymphoid leukemia (B-ALL). Total RNA was extracted from pediatric B-ALL patients (at diagnosis and after induction of therapy) and from healthy subjects. Total RNA was also extracted from different leukemia cell line models. The expression level of TEX41 was evaluated by q-RT-PCR. Also, the dataset deposited by St. Jude Children's Research Hospital was consulted. Furthermore, the silencing of TEX41 in RS4;11 cell line was obtained by 2'-Deoxy, 2'Fluroarabino Nucleic Acids (2'F-ANAs) Oligonucleotides, and the effect on cell proliferation was evaluated. Cell cycle progression and its regulators were analyzed by flow cytometry and immunoblotting. We exploited the St Jude Cloud database and found that TEX41 is a lncRNA primarily expressed in the case of B-ALL (n = 79) while its expression levels are low/absent for T-cell ALL (n = 25) and acute myeloid leukemia (n = 38). The association of TEX41 with B-ALL was confirmed by real-time PCR assays. TEX41 disclosed increased expression levels in bone marrow from patients with B-ALL at diagnosis, while its expression levels became low or absent when retested in Bone Marrow cells of the same patient after 1 month of induction therapy. Also, silencing experiments performed on RS4;11 cells showed that TEX41 downregulation impaired in vitro leukemic cell growth determining their arrest in the G2-M phase and the deregulation of cell cycle proteins. Our findings highlight that TEX41 is an upregulated lncRNA in the case of B-ALL and this feature makes it a novel potential biomarker for the diagnosis of this leukemia subtype in pediatric patients. Finally, TEX41 expression seems to be critical for leukemic proliferation, indeed, silencing experiments targeting TEX41 mRNA in the RS4;11 cell line hampered in vitro cell growth and cell cycle progression, by inducing G2-M arrest as confirmed propidium iodide staining and by the upregulation of p53 and p21 proteins.
Information about the long-term survival impact of hematopoietic stem cell transplant (HSCT) in adults with relapsed/refractory B-cell acute lymphoblastic leukaemia is limited. The objective was to ...conduct a systematic review identifying studies reporting survival in HSCT-receiving patients and apply parametric analyses to predict long-term survival.
Twenty-five relevant studies were identified. Analyses were conducted in 10 studies (n=503; "global" analysis) reporting overall survival (OS) data as Kaplan-Meier curves or at patient level. Four studies (n=217; "subgroup" analysis) measured OS from the point of HSCT. Patient-level data were recreated from Kaplan-Meier curves and pooled, with six models tested for longer-term extrapolation. Additionally, a sensitivity analysis was undertaken involving removal of data from the oldest study cohort (recruited between 1981-1997) to determine if the year which patients received HSCT impacted survival compared to post-2009 data.
Median OS and five-year survival probability were 11.4 months and 24.4% (95% CI, 20.5-28.5%) in the global analysis, and 12.0 months and 28.4% (95% CI, 22.1-34.9%) in the subgroup analysis. The generalised gamma and Gompertz models fit longer-term extrapolation criteria. The generalised gamma model predicted survival at 10.4% vs. 14.8% (15 years), 8.3% vs. 12.8% (20 years), and 6.9% vs. 11.4% (25 years) for the global and subgroup analysis, respectively. The Gompertz model predicted survival to plateau at 23% vs. 25.6% just before 10 years. The sensitivity analysis excluding older data found median survival increased two-fold (25.3 vs. 12 months).
Results synthesize long-term evidence of outcomes for HSCT-receiving patients, providing a basis for treatment comparison. Risk of death is low beyond four years and newer data appears correlated with improved outcomes.
Mature B cell acute lymphoblastic leukaemia (BAL) is characterised by French-American-British (FAB)-L3 morphology and the presence of surface immunoglobulin (sIgM) light chain restriction. BAL is ...also considered as the leukaemic phase of Burkitt lymphoma (BL), in which t (8; 14) (q24; q32) or its variants are related to the myelocytomatosis oncogene (MYC) rearrangement (MYCr) is usually present. However, BAL with lysine methyltransferase 2A (KMT2A, previously called Mixed lineage leukaemia, MLL) gene rearrangement (KMT2Ar, previously called MLLr) is rare. Three BAL patients with KMT2Ar were enrolled between January 2017 and November 2019, accounting for 1.37% of the B-ALL population in our hospital. We also reviewed 24 previously reported cases of BAL and KMT2Ar and analysed the features, treatment, and prognosis. Total 13 males and 14 females were enrolled in our research, and the average age at diagnosis was 19.5 + or - 4.95 months old. In these 27 patients, renal, central nervous system (CNS) and skin involvement were existent in 6, 4 and 3 patients, respectively; 26 patients (26/27) showed non-ALL-L3 morphology, while one patient is ALL-L3; overexpression of CD19 was detected in most cases, negative or suspicious expression of CD20 was found in 64% of patients. KMT2Ar was reported, but MYCr was not observed. 25 patients (25/27) achieved complete remission after chemotherapy or Stem cell transplantation. The patients were sensitive to chemotherapy, prospective event-free survival (pEFS) of BAL patients with KMT2Ar who received allogeneic haematopoietic stem cell transplantation (allo-HSCT) was higher than that in patients who received chemotherapy alone (83.33% vs 41.91%). BAL patients with KMT2Ar had unique manifestations, including younger age at diagnosis and overexpression of CD19; expression of CD20 was rare, and MYCr was undetectable. The pEFS was higher in patients undergoing allo-HSCT than in patients undergoing chemotherapy alone.
Background
IGH::DUX4 is frequently observed in 4% B‐cell acute lymphoblastic leukaemia patients. Regarding the IGH::DUX4‐driven transactivation and alternative splicing, which are the main reasons ...behind this acute leukaemia outbreak, it remains unclear how transcriptional cofactors contribute to this oncogenic process. Further investigation is required to elucidate their specific role in leukaemogenesis.
Methods
In order to investigate the cofactors of IGH::DUX4, integrated mining of Chromatin immunoprecipitation (ChIP)‐sequencing and RNA‐sequencing of leukaemia cells and patient samples were conducted. Furthermore, to elucidate the synergistic interaction between transcription factor 12 (TCF12) and IGH::DUX4, knockdown and knockout experiment, mammalian two‐hybridisation assay, co‐immunoprecipitation and in situ proximity ligation assays were carried out. Additionally, to further investigate the direct interaction between TCF12 and IGH::DUX4, AI‐based structural simulations were utilised. Finally, to validate the synergistic role of TCF12 in promoting IGH::DUX4 leukaemia, cell proliferation, apoptosis and drug sensitivity experiments were performed.
Results
In this study, we observed that the IGH::DUX4 target gene TCF12 might be an important cofactor/helper for this oncogenic driver. The co‐expression of IGH::DUX4 and TCF12 resulted in enhanced DUX4‐driven transactivation. Supportively, knockdown and knockout of TCF12 significantly reduced expression of IGH::DUX4‐driven target genes in leukaemia REH (a precursor B‐cell leukaemia cell line) and NALM‐6 cells (a precursor B‐cell leukaemia cell line). Consistently, in TCF12 knockout cells, the expression of structure‐based TCF12 mutant, but not wild‐type TCF12, failed to restore the TCF12–IGH::DUX4 crosstalk and the synergistic transactivation. More importantly, the breakdown in TCF12–IGH::DUX4 cooperation impaired IGH::DUX4‐driven leukaemia cell survival, caused sensitivity to the chemotherapy.
Conclusions
Altogether, these results helped to define a previously unrecognised TCF12‐mediated positive self‐feedback regulatory mechanism in IGH::DUX4 leukaemia, which holds the potential to function as a pivotal drug target for the management of this particular form of leukaemia.
Highlights
Transcription factor 12 (TCF12) is a new novel cofactor in IGH::DUX4 transcriptional complexes/machinery.
TCF12 mediates a positive self‐feedback regulatory mechanism in IGH::DUX4‐driven oncogenic transaction.
IGH::DUX4–TCF12 structure/cooperation might represent a potent target/direction in future drug design against B‐cell acute lymphoblastic leukaemia.
The significance of these results presented in this manuscript is three‐fold: 1) identifying a novel co‐factor in IGH::DUX4 transcriptional complexes/machinery; 2) highlighting a TCF12‐mediated self‐feedback regulatory mechanism in oncogenic transaction; 3) revealing the structural basis of IGH::DUX4‐TCF12 cooperation that might be a potent target/direction in future drug design against B‐ALL leukaemia.
Acute lymphoblastic leukaemia (ALL) in adults is a rare and difficult-to-treat cancer that is characterised by excess lymphoblasts in the bone marrow. Although many patients achieve remission with ...chemotherapy, relapse rates are high and the associated impact on survival devastating. Most patients receive chemotherapy and for those whose overall fitness supports it, the most effective treatment to date is allogeneic stem cell transplant that can improve overall survival rates in part due to a ‘graft-versus-leukaemia’ effect. However, due to the rarity of this disease, and the availability of mature B-cell antigens on the cell surface, few new cancer antigens have been identified in adult B-ALL that could act as targets to remove residual disease in first remission or provide alternative targets for escape variants if and when current immunotherapy strategies fail. We have used RT-PCR analysis, literature searches, antibody-specific profiling and gene expression microarray analysis to identify and prioritise antigens as novel targets for the treatment of adult B-ALL.
Superior mediastinal syndrome secondary to an anterior mediastinal mass can be seen in acute lymphoblastic leukaemia (ALL) of T-cell lineage. We report a 3-year-old child with B-cell ALL, who ...presented with the superior mediastinal syndrome. The CT scan chest showed a huge anterior mediastinal mass and the peripheral blood immunophenotyping showed B-cell ALL. High-risk remission induction chemotherapy was given and he achieved remission by the end of induction therapy, both in terms of medullary and extramedullary disease, and is on maintenance chemotherapy now. This is the first reported case of a paediatric B-cell ALL presenting with superior mediastinal syndrome secondary to an anterior mediastinal mass.
Introduction: Regulation in adaptive immune response balances a fine line that prevents instigation of self-damage or fall into unresponsiveness permitting abnormal cell growth. Mechanisms that keep ...this balance in check include regulatory T cells (Tregs). Tregs consist of a small but heterogeneous population, which may be identified by the phenotype, CD3+CD4+CD25+CD127−. The role of Tregs in pathogenesis of cancers is thus far supported by evidence of increased Tregs in various cancers and may contribute to poorer prognosis. Tregs may also be important in acute leukaemias.
Objective: A review of the literature on Tregs in acute leukaemias was conducted and Tregs were determined in B-cell acute lymphoblastic leukaemias (ALLs).
Results: Studies on Tregs in B-cell ALL are few and controversial. We observed a significantly increased percentage of Tregs (mean±SD, 9.72 ± 3.79% vs. 7.05 ± 1.74%; P = 0.047) in the bone marrow/peripheral blood of ALL (n = 17) compared to peripheral blood of normal controls (n = 35). A positive trend between Tregs and age (R = 0.474, P = 0.055, n = 17) implicates this factor of poor prognosis in B-cell ALL.
Discussion: Tregs in cancer are particularly significant in immunotherapy. The manipulation of the immune system to treat cancer has for a long time ignored regulatory mechanisms inducible or in place. In lymphoma studies, tumour-specific mechanisms that are unlike conventional methods in the induction of Tregs have been hypothesized. In addition, tumour-infiltrating Tregs may present different profiles from peripheral blood pictures. Tregs will continue to be dissected to reveal its mysteries and their impact on clinical significance.
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