TRANSFORMATION OF MYELODYSPLASTIC SYNDROME INTO ACUTE MYELOBLASTIC LEUKEMIA (CLINICAL CASE).

Despite the availability of modern methods for diagnosing and treating myelodysplastic syndrome (MDS) in the arsenal of a hematologist, even with an adequate treatment strategy, it is not always possible to predict the timing of transformation of the disease into acute myeloid leukemia. The clinical case we presented demonstrates the rapid transformation of MDS into acute myeloid leukemia in a relatively young patient whose prognosis turned out to be poorly predictable despite a change in therapy.

Screening of Myelodysplastic Syndromes Using Research Parameters of Complete Blood Count: Automated Detection of Dysplasia.

Myelodysplastic syndromes (MDS) present with polymorphic and non-specific diagnostic features Research parametersfrom hematology analyzers may be useful to discriminate MDS-related cytopenia.Parameters such as Neu X (related to the cytoplasmic complexity) and Neu Y (related to nucleic acid content) show promise to detect dysplasia of MDS and aid to recognize MDS from cytopenias of other etiologies.

Myeloid sarcoma in JAK2-positive myelodysplastic neoplasms with fibrosis: a case report and literature review.

Myeloid sarcoma (MS) occurs in patients with acute myeloid leukemia (AML). In rare cases, MS can represent a form of blast transformation in patients with myeloproliferative neoplasms (MPN), myelodysplastic neoplasms (MDS), or MDS/MPN. The most frequent chromosomal alterations in MS are t(8;21) or inv(16), with other alterations being reported. Cases of MS in Janus kinase 2 (JAK2)-positive MDS with fibrosis are exceedingly rare. Here, we describe such a case. To the best of our knowledge, this is the first report of a JAK2 V617F mutation-positive MDS case occurring concurrently with MS involving the posterior aspect of the left seventh rib. No clear association has been previously demonstrated between the intramedullary AML cytogenetics and extramedullary disease occurrence. Interestingly, samples from the intramedullary MDS and extramedullary mass in this patient presented the same JAK2 V617F mutation. Following a treatment regimen of azacitidine and venetoclax, the patient achieved complete remission. The chest CT scan showed that the seventh posterior rib mass disappeared. This case provides valuable information for the potential future treatment of this disease.

Flow cytometry in the differential diagnosis of myelodysplastic neoplasm with low blasts and cytopenia of other causes.

Background: Myelodysplastic neoplasms (MDS) are characterized by cytopenia, morphologic dysplasia, and genetic abnormalities. Multiparameter flow cytometry (FCM) is recommended in the diagnostic work-up of suspected MDS, but alone is not sufficient to establish the diagnosis. Our aim was to investigate the diagnostic power of FCM in a heterogeneous population of patients with cytopenia, excluding cases with increased blast count. Methods: We analyzed bone marrow samples from 179 patients with cytopenia (58 MDS, 121 non-MDS) using a standardized 8-color FCM method. We evaluated the sensitivity, specificity, and accuracy of several simple diagnostic approaches, including Ogata score, extended Ogata score, the WHO and ELN iMDSFlow recommended "3 aberrations in two cell compartments method," and the combination of the Ogata score and "3 aberrations in two cell compartments method." The patients were followed until the diagnosis was confirmed, with a median follow-up of 2 months (range 0.2-27). Results: The combination of Ogata score and "3 aberrations in two cell compartments method" achieved the highest diagnostic accuracy (78%) with sensitivity and specificity 61% and 86%, respectively. When using only the "3 aberrations in two cell compartments method," the accuracy was 77% with a sensitivity of 72% and a specificity of 79%. The most frequently observed etiologies among the false positive cases were substrate deficiencies, inflammation/infection, or toxic effects. MDS can be excluded in all these cases after a thorough clinical evaluation and a relatively short follow-up. Conclusion: FCM remains an important but supplementary part in an integrated diagnostic process of MDS with low blasts. The combination of the Ogata score and the "3 aberrations in two cell compartments method" slightly improves accuracy compared to the detection of "3 aberrations in two cell compartments method" alone.

[Clinical efficacy of allogeneic hematopoietic stem cell transplantation for myelodysplastic syndrome-evolved acute myeloid leukemia].

Objective: The outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for myelodysplastic syndromes-evolved acute myeloid leukemia (MDS-AML) were explored. Methods: A retrospective review was conducted for 54 patients with MDS-AML treated with allo-HSCT in the Institute of Hematology and Blood Disease Hospital from January 2018 to August 2022. The clinical effects after transplantation were observed, and the related risk factors influencing prognosis were explored. Results: Of the total 54 patients, 26 males, 28 females, and 53 patients achieved hematopoietic reconstruction. After a median follow-up of 597 (15-1 934) days, the 1 year overall survival (OS) rate, disease-free survival (DFS) rate, relapse rate (CIR) and non-relapse mortality (NRM) rate were 75.8%±5.8%, 72.1%±6.1%, 12.7%±4.9%, and 17.1%±5.2%, respectively. The 3 year estimated OS, DFS, CIR, and NRM rates were 57.8%±7.5%, 58.1%±7.2%, 23.2%±6.6%, and 23.7%±6.6%, respectively. The cumulative incidence of acute graft-versus-host disease (aGVHD) was 57.5%±6.9%, and the cumulative incidence of chronic graft-versus-host disease (cGVHD) was 48.4%±7.7%. Hematopoietic cell transplantation comorbidity index (HCT-CI) before transplantation was ≥2, minimal residual disease (MRD) was positive on the day of reconstitution, grade Ⅲ/Ⅳ aGVHD, bacterial or fungal infection and no cGVHD after transplantation were adverse prognostic factors for OS (P<0.05). COX regression model for multivariate analysis showed that HCT-CI score before transplantation, bone marrow MRD on the day of response, grade Ⅲ or Ⅳ aGVHD, and cGVHD after transplantation were the independent adverse factors for OS (P=0.001, HR=6.981, 95%CI 2.186-22.300; P=0.010, HR=6.719, 95%CI 1.572-28.711; P=0.026, HR=3.386, 95%CI 1.158-9.901; P=0.006, HR=0.151, 95%CI 0.039-0.581) . Conclusion: For patients with MDS-AML and high risk of relapse, allogeneic transplantation must be considered as soon as possible. The enhanced management of post-transplantation complications and maintenance treatment should be provided whenever possible after transplantation.

[Clinical features and prognostic factors of advanced myelodysplastic syndromes in children].

Objective: To investigate the clinical features and prognostic factors of advanced myelodysplastic syndromes (MDS) in children. Methods: Clinical data of children diagnosed with advanced MDS in the Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences, between September 2009 and April 2022 were retrospectively collected. Follow-up assessments were performed through telephone interviews and the review of medical records until May 1, 2023. The clinical features of children with advanced MDS were summarized by analyzing chromosomal karyotype tests, second-generation gene sequencing results. Multivariate Cox regression analysis was used to investigate the prognostic factors of advanced MDS in children. Results: A total of 69 children, comprising 49 males and 20 females, aged [M (Q1, Q3)] 8 (5, 10) years, were enrolled in the study. Sixty-seven cases underwent chromosomal karyotype testing, of which 42 cases (62.7%) had abnormal karyotypes, with monosomy 7 the most common in 17 cases (25.4%). Forty-three cases underwent next-generation sequencing, with mutations in the SETBP1, NRAS, PTPN11 and RUNX1 genes more common, identified in 12 cases (27.9%), 9 cases (20.9%), 8 cases(18.6%), and 8 cases(18.6%), respectively. The follow-up time [M (Q1, Q3)] was 26 (13, 56) months and the 5-year overall survival rate was 56%(95%CI: 44.4%-70.5%). The 5-year overall survival rate for children who underwent hematopoietic stem cell transplantation (HSCT) was higher than that of children who did not undergo HSCT (73.9% vs 29.1%, P<0.001). HSCT (HR=0.118, 95%CI: 0.037-0.372, P<0.001) was a protective factor for the overall survival rate of children with advanced MDS. Serum ferritin level>356.3 µg/L (HR=6.497, 95%CI: 2.068-20.415, P=0.001) and moderate to severe splenomegaly (HR=4.075, 95%CI: 1.174-14.141, P=0.027) were risk factors for the overall survival rate of children with advanced MDS. Conclusions: Monosomy 7 was the most common abnormal karyotype and SETBP1 was the gene that had the highest mutation frequency in children with advanced MDS. HSCT, increased ferritin and moderate to severe splenomegaly are prognostic factors influencing the overall survival rate of children with advanced MDS.

[Analysis of the efficacy and prognostic factors of allogeneic hematopoietic stem cell transplantation in patients with myelodysplastic syndrome with blastomycosis and survival comparison of different subtypes after the WHO 2022 reclassification].

Objective: To evaluate the efficacy and prognostic factors of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with myelodysplastic syndrome accompanied by myelodysplasia (MDS-EB) and to compare the prognosis of different subtypes of patients classified by World Health Organization (WHO) 2022. Methods: A total of 282 patients with MDS-EB who underwent allo-HSCT at the Hematology Hospital of the Chinese Academy of Medical Sciences from October 2006 to December 2022 were included in the study. The WHO 2022 diagnostic criteria reclassified MDS into three groups: myelodysplastic tumors with type 1/2 of primitive cell proliferation (MDS-IB1/IB2, 222 cases), MDS with fibrosis (MDS-f, 41 cases), and MDS with biallelic TP53 mutation (MDS-biTP53, 19 cases). Their clinical data were retrospectively analyzed. Results: ① The median age of 282 patients was 46 (15-66) years, with 191 males and 91 females. Among them, 118 (42% ) and 164 (58% ) had MDS-EB1 and MDS-EB2, respectively. ②Among the 282 patients, 256 (90.8% ) achieved hematopoietic reconstruction after transplantation, with 11 (3.9% ) and 15 (5.3% ) having primary and secondary implantation dysfunctions, respectively. The cumulative incidence of acute graft-versus-host disease (GVHD) 100 days post-transplantation was (42.6±3.0) %, and the cumulative incidence of grade Ⅱ-Ⅳ acute GVHD was (33.0±2.8) %. The cumulative incidence of chronic GVHD 1 year post-transplantation was (31.0±2.9) %. Post-transplantation, 128 (45.4% ), 63 (22.3% ), 35 (12.4% ), and 17 patients (6.0% ) developed cytomegalovirus infection, bacteremia, pulmonary fungal infection, and Epstein-Barr virus infection. ③The median follow-up time post-transplantation was 22.1 (19.2-24.7) months, and the 3-year overall survival (OS) and disease-free survival (DFS) rates were 71.9% (95% CI 65.7% -78.6% ) and 63.6% (95% CI 57.2% -70.7% ), respectively. The 3-year non-recurrent mortality rate (NRM) is 17.9% (95% CI 13.9% -22.9% ), and the 3-year cumulative recurrence rate (CIR) is 9.8% (95% CI 6.7% -13.7% ). The independent risk factors affecting OS post-transplantation include monocyte karyotype (P=0.004, HR=3.26, 95% CI 1.46-7.29), hematopoietic stem cell transplantation complication index (HCI-CI) of ≥3 points (P<0.001, HR=2.86, 95% CI 1.72-4.75), and the occurrence of acute gastrointestinal GVHD of grade Ⅱ-Ⅳ (P<0.001, HR=5.94, 95% CI 3.50-10.10). ④The 3-year OS and DFS rates in the MDS-IB1/IB2 group post-transplantation were better than those in the MDS-biTP53 group [OS: 72.0% (95% CI 63.4% -80.7% ) vs 46.4% (95% CI 26.9% -80.1% ), P=0.020; DFS: 67.4% (95% CI 60.3% -75.3% ) vs 39.7% (95% CI 22.3% -70.8% ), P=0.015]. The 3-year CIR was lower than that of the MDS-biTP53 group [7.3% (95% CI 4.3% -11.4% ) vs 26.9% (95% CI 9.2% -48.5% ), P=0.004]. The NRM at 3 years post-transplantation in the MDS-IB1/IB2, MDS-f, and MDS-biTP53 groups were 16.7% (95% CI 12.1% -22.1% ), 20.5% (95% CI 9.4% -34.6% ), and 26.3% (95% CI 9.1% -47.5% ), respectively (P=0.690) . Conclusion: Allo-HSCT is an effective treatment for MDS-EB, with monomeric karyotype, HCI-CI, and grade Ⅱ-Ⅳ acute gastrointestinal GVHD as independent risk factors affecting the patient's OS. The WHO 2022 classification helps distinguish the efficacy of allo-HSCT in different subgroups of patients. Allo-HSCT can improve the poor prognosis of patients with MDS-f, but those with MDS-biTP53 have a higher risk of recurrence post-transplantation.

Application of m6A regulators to predict transformation from myelodysplastic syndrome to acute myeloid leukemia via machine learning.

Myelodysplastic syndrome (MDS) frequently transforms into acute myeloid leukemia (AML). Predicting the risk of its transformation will help to make the treatment plan. Levels of expression of N6-methyladenosine (m6A) regulators is difference in patients with AML, MDS, and MDS transformed into AML. Seven machine learning algorithms were established based on all of 26 m6A or main differentially expressed m6A regulator genes, and attempted to establish a risk assessment method to distinguish AML from MDS and predict the transformation of MDS into AML. In collective of m6A regulators sets, support vector machine (SVM) and neural network (NNK) model best distinguished AML or MDS from control, with area under the ROC curve (AUROC) 0.966 and 0.785 respectively. The SVM model best distinguished MDS from AML, with AUROC 0.943, sensitivity 0.862, specificity 0.864, and accuracy 0.864. In differentially expressed gene sets, SVM and logistic regression (LR) model best distinguished AML or MDS from control, with AUROC 0.945 and 0.801 respectively. The random forest (RF) model best distinguished between MDS and AML, with AUROC 0.928, sensitivity 0.725, specificity 0.898, and accuracy 0.818. For predictive capacity of MDS transformed into AML, SVM model showed the best predicted in collective m6A regulators sets, with AUROC 0.781 and accuracy 0.740. The LR model showed the best predicted in differential expression m6A regulators sets, with AUROC 0.820 and accuracy 0.760. All results suggested that machine learning model established by m6A regulators can be used to distinguished AML or MDS from control, distinguished AML from MDS and predicted the transformation of MDS into AML.

Phase 1 dose escalation study of the MDM2 inhibitor milademetan as monotherapy and in combination with azacitidine in patients with myeloid malignancies.

BACKGROUND: Mouse double minute-2 homolog (MDM2) plays a key role in downregulating p53 activity in hematologic malignancies, and its overexpression is associated with poor outcomes. METHODS: This phase 1 study assessed the safety and efficacy of different dosing regimens of the MDM2 inhibitor milademetan as monotherapy and in combination with azacitidine (AZA) in patients with relapsed or refractory acute myeloid leukemia or high-risk myelodysplastic syndromes. RESULTS: Seventy-four patients (monotherapy, n = 57; milademetan-AZA combination, n = 17) were treated. The maximum tolerated dose of milademetan was 160 mg once daily given for the first 14-21 days of 28-day cycles as monotherapy and on Days 5-14 in combination with AZA. Dose-limiting toxicities were gastrointestinal, fatigue, or renal/electrolyte abnormalities. Treatment-emergent adverse events related to milademetan occurred in 82.5% and 64.7% of participants in the monotherapy and AZA combination arms, respectively. Two participants (4.2%) in the monotherapy arm achieved complete remission (CR), and 1 (2.1%) achieved CR with incomplete blood count recovery (CRi). Two participants (13.3%) achieved CRi in the combination arm. New TP53 mutations, detected only during milademetan monotherapy, were found pre-existing below standard detection frequency by droplet digital polymerase chain reaction. INTERPRETATION: Milademetan was relatively well tolerated in this population; however, despite signals of activity, clinical efficacy was minimal.

WT1 gene mutations impact post-transplant relapse in myelodysplastic syndrome with excess blasts 2 patients.

Wilms tumor 1 (WT1) gene mutations are infrequent in myelodysplastic syndrome (MDS), but MDS with WT1 mutations (WT1mut) is considered high risk for acute myeloid leukemia (AML) transformation. The influence of WT1 mutations in patients with MDS after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is unclear. We performed a retrospective analysis of 136 MDS with excess blasts 2 (MDS-EB2) patients with available WT1 status who underwent their first allo-HSCT between 2017 and 2022 in our center. There were 20 (20/136, 15%) cases in the WT1mut group and 116 (116/136, 85%) cases in the WT1 wild-type (WT1wt) group. WT1mut patients had a higher 2-year cumulative incidence of relapse (CIR) than WT1wt cases (26.2% vs. 9.4%, p = 0.037) after allo-HSCT. Multivariate analysis of relapse showed that WT1 mutations (HR, 6.0; p = 0.002), TP53 mutations (HR, 4.2; p = 0.021), and ≥ 5% blasts in bone marrow (BM) at transplantation (HR, 6.6; p = 0.004) were independent risk factors for relapse. Patients were stratified into three groups according to the risk factors. Two-year CIR differed significantly in high-, intermediate-, and low-risk groups (31.8%, 11.6%, and 0%, respectively). Hence, WT1 mutations may be related to post-transplant relapse in patients with MDS-EB2, which warrants further study.

The roles of phosphorylation of signaling proteins in the prognosis of acute myeloid leukemia.

Signaling pathways of Retinoblastoma (Rb) protein, Akt-kinase, and Erk-kinase (extracellular signal-regulated kinase) have an important role in the pathogenesis of acute myeloid leukemia. Constitutive activation of these proteins by phosphorylation contributes to cell survival by regulation of cell cycle, proliferation and proapoptotic signaling processes. According to previous data phosphorylated forms of these proteins represent a worse outcome for cancer patients. We investigated the presence of phosphorylated Rb (P-Rb), Akt (P-Akt) and Erk (P-Erk) proteins by Western blot technique using phospho-specific antibodies in bone marrow or peripheral blood samples of 69 AML patients, 36 patients with myelodysplastic syndrome (MDS) and 10 healthy volunteers. Expression level of PTEN (Phosphatase and tensin homolog) and PHLPP (PH domain and leucine-rich repeat Protein Phosphatase) phosphatases, the negative regulators of Akt kinase pathway were also examined. We tested the effect of these proteins on survival and on the correlation with known prognostic features in AML. We found 46.3% of AML patients had detectable P-Rb, 34.7% had P-Akt and 28.9% had P-Erk protein. 66.1% of patients expressing PTEN, 38.9% PHLPP, 37.2% both PTEN and PHLPP and 32.2% neither PTEN nor PHLPP phosphatases. Compared to nucleophosmin mutation (NPMc) negative samples P-Erk was significantly less in nucleophosmin mutated patients, P-Rb was significantly less in patients' group with more than 30 G/L peripheral leukocyte count by diagnosis. PHLPP was significantly present in FAB type M5. The expression of P-Rb represented significant better overall survival (OS), while P-Akt represented significantly worse event-free survival (EFS) in unfavorable cytogenetics patients. The presence of both PHLPP and PTEN phosphatases contributes to better OS and EFS, although the differences were not statistically significant. We confirmed significant positive correlation between P-Akt and PHLPP. Assessing the phosphorylation of Rb, Akt and Erk may define a subgroup of AML patients who would benefit especially from new targeted treatment options complemented the standard chemotherapy, and it may contribute to monitoring remission, relapse or progression of AML.

A practical approach on the classifications of myeloid neoplasms and acute leukemia: WHO and ICC.

In 2022, two new classifications of myeloid neoplasms and acute leukemias were published: the 5th edition WHO Classification (WHO-HAEM5) and the International Consensus Classification (ICC). As with prior classifications, the WHO-HAEM5 and ICC made updates to the prior classification (revised 4th edition WHO Classification, WHO-HAEM4R) based on a consensus of groups of experts, who examined new evidence. Both WHO-HAEM5 and ICC introduced several new disease entities that are based predominantly on genetic features, superseding prior morphologic definitions. While it is encouraging that two groups independently came to similar conclusions in updating the classification of myeloid neoplasms and acute leukemias, there are several divergences in how WHO-HAEM5 and ICC define specific entities as well as differences in nomenclature of certain diseases. In this review, we highlight the similarities and differences between the WHO-HAEM5 and ICC handling of myeloid neoplasms and acute leukemias and present a practical approach to diagnosing and classifying these diseases in this current era of two divergent classification guidelines.

Computing cell state discriminates the aberrant hematopoiesis and activated microenvironment in Myelodysplastic syndrome (MDS) through a single cell genomic study.

BACKGROUND: Myelodysplastic syndrome (MDS) is a complicated hematopoietic malignancy characterized by bone marrow (BM) dysplasia with symptoms like anemia, neutropenia, or thrombocytopenia. MDS exhibits considerable heterogeneity in prognosis, with approximately 30% of patients progressing to acute myeloid leukemia (AML). Single cell RNA-sequencing (scRNA-seq) is a new and powerful technique to profile disease landscapes. However, the current available scRNA-seq datasets for MDS are only focused on CD34+ hematopoietic progenitor cells. We argue that using entire BM cell for MDS studies probably will be more informative for understanding the pathophysiology of MDS. METHODS: Five MDS patients and four healthy donors were enrolled in the study. Unsorted cells from BM aspiration were collected for scRNA-seq analysis to profile overall alteration in hematopoiesis. RESULTS: Standard scRNA-seq analysis of unsorted BM cells successfully profiles deficient hematopoiesis in all five MDS patients, with three classified as high-risk and two as low-risk. While no significant increase in mutation burden was observed, high-risk MDS patients exhibited T-cell activation and abnormal myelogenesis at the stages between hematopoietic stem and progenitor cells (HSPC) and granulocyte-macrophage progenitors (GMP). Transcriptional factor analysis on the aberrant myelogenesis suggests that the epigenetic regulator chromatin structural protein-encoding gene HMGA1 is highly activated in the high-risk MDS group and moderately activated in the low-risk MDS group. Perturbation of HMGA1 by CellOracle simulated deficient hematopoiesis in mouse Lineage-negative (Lin-) BM cells. Projecting MDS and AML cells on a BM cell reference by our newly developed MarcoPolo pipeline intuitively visualizes a connection for myeloid leukemia development and abnormalities of hematopoietic hierarchy, indicating that it is technically feasible to integrate all diseased bone marrow cells on a common reference map even when the size of the cohort reaches to 1,000 patients or more. CONCLUSION: Through scRNA-seq analysis on unsorted cells from BM aspiration samples of MDS patients, this study systematically profiled the development abnormalities in hematopoiesis, heterogeneity of risk, and T-cell microenvironment at the single cell level.

RSL3 enhances ROS-mediated cell apoptosis of myelodysplastic syndrome cells through MYB/Bcl-2 signaling pathway.

Myelodysplastic syndromes (MDS) are clonal hematopoietic malignancies and seriously threaten people's health. Current therapies include bone marrow transplantation and several hypomethylating agents. However, many elderly patients cannot benefit from bone marrow transplantation and many patients develop drug resistance to hypomethylating agents, making it urgent to explore novel therapy. RSL3 can effectively induce ferroptosis in various tumors and combination of RSL3 and hypomethylating agents is promising to treat many tumors. However, its effect in MDS was unknown. In this study, we found that RSL3 inhibited MDS cell proliferation through inducing ROS-dependent apoptosis. RSL3 inhibited Bcl-2 expression and increased caspase 3 and PARP cleavage. RNA-seq analysis revealed that MYB may be a potential target of RSL3. Rescue experiments showed that overexpression of MYB can rescue MDS cell proliferation inhibition caused by RSL3. Cellular thermal shift assay showed that RSL3 binds to MYB to exert its function. Furthermore, RSL3 inhibited tumor growth and decreased MYB and Bcl-2 expression in vivo. More importantly, RSL3 decreased the viability of bone marrow mononuclear cells (BMMCs) isolated from MDS patients, and RSL3 had a synergistic effect with DAC in MDS cells. Our studies have uncovered RSL3 as a promising compound and MYB/Bcl-2 signaling pathway as a potential target for MDS treatment.

Acute therapy-related myelodysplastic syndromes following capecitabine and oxaliplatin therapy in gastric malignant tumor: A case report.

RATIONAL: Patients with gastric cancer show a relatively low incidence of developing secondary myelodysplastic syndrome (MDS). PATIENT CONCERNS: A 60-year-old man was admitted because of pain and discomfort in the upper abdomen and intermittent abdominal pain. DIAGNOSES: Ulcerative moderately poorly differentiated adenocarcinoma (pT2N2M0G3, stage IIB) and MDS. INTERVENTIONS: The patient underwent chemotherapy with oxaliplatin (OXP, intravenously guttae on day 1) plus capecitabine (CAP, bis in die orally on day 1-14). The patient developed degree III myelosuppression after OXP plus CAP chemotherapy and MDS was subsequently confirmed by diagnosis of the bone marrow biopsy. Temporary but significant hematological improvements were observed after the patient received corresponding treatment, which helped achieve remission and improve pancytopenia. OUTCOMES: The patient presented partial remission after corresponding treatment and no other complications have been recorded. LESSONS: Acute MDS is an unusual adverse effect induced by OXP plus CAP chemotherapy. It is urgent to suggest implementing a supplementary assessment or examination for patients receiving these therapies in future cases.

A case of recurrent erythema induratum of Bazin in a patient with myelodysplastic syndrome.

We describe a case of erythema induratum of Bazin (EIB) that presented recurrently on the extremities during treatment with anti-tuberculosis medications. The anti-tuberculosis medications were effective, so they were continued despite the occurrence of the EIB lesions, and those lesions disappeared 5 months after first appearing. EIB is currently considered a multifactorial disorder with many different causes, with tuberculosis being an example, and it is thought to be a hypersensitive immune response to Mycobacterium tuberculosis. The clinical manifestations may fluctuate depending on the immune response of the host. Our patient was affected with myelodysplastic syndrome, and we believe that this was a major factor that interfered with a normal immune response. This case illustrates the importance of providing intensive anti-tuberculosis treatment from the start, and in cases where EIB co-presents, to continue this treatment until the end, in order to prevent relapse.

Single-cell transcriptional profile of CD34+ hematopoietic progenitor cells from del(5q) myelodysplastic syndromes and impact of lenalidomide.

While myelodysplastic syndromes with del(5q) (del(5q) MDS) comprises a well-defined hematological subgroup, the molecular basis underlying its origin remains unknown. Using single cell RNA-seq (scRNA-seq) on CD34+ progenitors from del(5q) MDS patients, we have identified cells harboring the deletion, characterizing the transcriptional impact of this genetic insult on disease pathogenesis and treatment response. Interestingly, both del(5q) and non-del(5q) cells present similar transcriptional lesions, indicating that all cells, and not only those harboring the deletion, may contribute to aberrant hematopoietic differentiation. However, gene regulatory network (GRN) analyses reveal a group of regulons showing aberrant activity that could trigger altered hematopoiesis exclusively in del(5q) cells, pointing to a more prominent role of these cells in disease phenotype. In del(5q) MDS patients achieving hematological response upon lenalidomide treatment, the drug reverts several transcriptional alterations in both del(5q) and non-del(5q) cells, but other lesions remain, which may be responsible for potential future relapses. Moreover, lack of hematological response is associated with the inability of lenalidomide to reverse transcriptional alterations. Collectively, this study reveals transcriptional alterations that could contribute to the pathogenesis and treatment response of del(5q) MDS.

The DNA Methyltransferase Inhibitor 5-Aza-4'-thio-2'-Deoxycytidine Induces C>G Transversions and Acute Lymphoid Leukemia Development.

DNA methyltransferase inhibitors (DNMTi), most commonly cytidine analogs, are compounds that decrease 5'-cytosine methylation. DNMTi are used clinically based on the hypothesis that cytosine demethylation will lead to re-expression of tumor suppressor genes. 5-Aza-4'-thio-2'-deoxycytidine (Aza-TdCyd or ATC) is a recently described thiol-substituted DNMTi that has been shown to have anti-tumor activity in solid tumor models. In this study, we investigated the therapeutic potential of ATC in a murine transplantation model of myelodysplastic syndrome. ATC treatment led to the transformation of transplanted wild-type bone marrow nucleated cells into lymphoid leukemia, and healthy mice treated with ATC also developed lymphoid leukemia. Whole-exome sequencing revealed 1,000 acquired mutations, almost all of which were C>G transversions in a specific 5'-NCG-3' context. These mutations involved dozens of genes involved in human lymphoid leukemia, such as Notch1, Pten, Pax5, Trp53, and Nf1. Human cells treated in vitro with ATC showed 1,000 acquired C>G transversions in a similar context. Deletion of Dck, the rate-limiting enzyme for the cytidine salvage pathway, eliminated C>G transversions. Taken together, these findings demonstrate a highly penetrant mutagenic and leukemogenic phenotype associated with ATC. Significance: Treatment with a DNA methyltransferase inhibitor generates a distinct mutation signature and triggers leukemic transformation, which has important implications for the research and clinical applications of these inhibitors.