Lysosomal cation channel TRPML1 suppression sensitizes acute myeloid leukemia cells to chemotherapeutics by inhibiting autophagy.

Despite the implementation of novel therapeutic regimens and extensive research efforts, chemoresistance remains a formidable challenge in the treatment of acute myeloid leukemia (AML). Notably, the involvement of lysosomes in chemoresistance has sparked interest in developing lysosome-targeted therapies to sensitize tumor cells to currently approved chemotherapy or as innovative pharmacological approaches. Moreover, as ion channels on the lysosomal membrane are critical regulators of lysosomal function, they present potential as novel targets for enhancing chemosensitivity. Here, we discovered that the expression of a lysosomal cation channel, namely transient receptor potential mucolipin 1 (TRPML1), was elevated in AML cells. Inhibiting TRPML1 individually does not impact the proliferation and apoptosis of AML cells. Importantly, inhibition of TRPML1 demonstrated the potential to modulate the sensitivity of AML cells to chemotherapeutic agents. Exploration of the underlying mechanisms revealed that suppression of TRPML1 impaired autophagy while concurrently increasing the production of reactive oxygen species (ROS) and ROS-mediated lipid peroxidation (Lipid-ROS) in AML cells. Finally, the knockdown of TRPML1 significantly reduced OCI-AML3 tumor growth following chemotherapy in a mouse model of human leukemia. In summary, targeting TRPML1 represents a promising approach for combination therapy aimed at enhancing chemosensitivity in treating AML.

Lysosomal K+ channel TMEM175 promotes apoptosis and aggravates symptoms of Parkinson's disease.

Lysosomes are degradative organelles and play vital roles in a variety of cellular processes. Ion channels on the lysosomal membrane are key regulators of lysosomal function. TMEM175 has been identified as a lysosomal potassium channel, but its modulation and physiological functions remain unclear. Here, we show that the apoptotic regulator Bcl-2 binds to and inhibits TMEM175 activity. Accordingly, Bcl-2 inhibitors activate the channel in a caspase-independent way. Increased TMEM175 function inhibits mitophagy, disrupts mitochondrial homeostasis, and increases production of reactive oxygen species (ROS). ROS further activates TMEM175 and thus forms a positive feedback loop to augment apoptosis. In a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of Parkinson's disease (PD), knockout (KO) of TMEM175 mitigated motor impairment and dopaminergic (DA) neuron loss, suggesting that TMEM175-mediated apoptosis plays an important role in Parkinson's disease (PD). Overall, our study reveals that TMEM175 is an important regulatory site in the apoptotic signaling pathway and a potential therapeutic target for Parkinson's disease (PD).

Longitudinal Serum Proteomics Characterization of CD19-CAR-T Cell Therapy for B-Cell Malignancies.

Chimeric antigen receptor (CAR)-modified T cells have demonstrated remarkable efficacy in treating B-cell leukemia. However, treated patients may potentially develop side effects, such as cytokine release syndrome (CRS), the mechanisms of which remain unclear. Here, we collected 43 serum samples from eight patients with B-cell acute lymphoblastic leukemia (B-ALL) before and five time points after CD19-specific CAR-T cell treatment. Using TMTpro 16-plex-based quantitative proteomics, we quantified 1151 proteins and profiled the longitudinal proteomes analysis of each patient. Seven days after therapy, we found the most dysregulated inflammatory proteins. Lipid metabolism proteins, including APOA1, decreased after therapy, reached their minimum after 7 days, and then gradually recovered. Hence, APOA1 has been selected as a potential biomarker of the CRS disease progression. Furthermore, we identified CD163 as a potential biomarker of CRS severity. These two biomarkers were successfully validated using targeted proteomics in an independent cohort. Our study provides new insights into CAR-T cell therapy-induced CRS. The biomarkers we identified may help develop targeted drugs and monitoring strategies.

Cytokine release syndrome and relevant factors of CD19 targeted chimeric antigen receptor T cell therapy in relapsed/refractory B cell hematological malignancies.

OBJECTIVES AND METHODS: We reviewed the outcomes of 77 episodes of CD19 CAR-T therapy in 67 patients with B cell hematological malignancies from October 2016 to January 2020. Factors related to the grade of cytokine release syndrome (CRS) were explored by multivariate analysis, nonparametric test was conducted to explore the correlation between CRS and response. Kaplan-Meier curves were used to indicate survival profiles, and the correlation between CRS and survival was determined by the log-rank test. RESULTS: The rate of complete remission (CR) was 74.0% (57/77). CRS of any grade occurred in 68 of 77 episodes (grade 1: 32.5%, grade 2: 24.7%, grade 3: 22.1%, grade 4: 6.5%, grade 5: 2.6%). Patients with a history of transplantation had less severe CRS, and dose escalation-based infusion reduced the severity of CRS. Severe CRS was related to a higher CR rate but had no significant impact on event-free survival (EFS), relapse-free survival (RFS), or overall survival (OS). CONCLUSION: As a common adverse reaction of CAR-T therapy, the severity of CRS can be alleviated by dose escalation infusion, a history of transplantation was correlated with less severe CRS. Severe CRS was related to better response but was unrelated to long-term survival.

Better outcomes of modified myeloablative conditioning without antithymocyte globulin versus myeloablative conditioning in cord blood transplantation for hematological malignancies: A retrospective (development) and a prospective (validation) study.

Cord blood transplantation (CBT) is an effective option for treating hematological malignancies, but graft failure (GF) remains the primary cause of therapy failure. Thus, based on myeloablative conditioning (MAC) of busulfan with cyclophosphamide (Bu/Cy) or total body irradiation with Cy (TBI/Cy), fludarabine (Flu) was added to Bu/Cy and cytarabine (CA) to TBI/Cy for a modified myeloablative conditioning (MMAC). To compare the prognosis of MMAC with MAC, we conducted a retrospective study including 58 patients who underwent CBT with MAC or MMAC from 2000 to 2011. Neutrophil and platelet engraftment rate, overall survival (OS) and disease free survival (DFS) were significantly higher in the MMAC group (adjusted hazard ratio [HR], 2.58, 2.43, 0.36 and 0.37; p < 0.01, p = 0.01, p = 0.02 and p = 0.02, separately). Nonrelapse mortality (NRM) was comparable (p = 0.183). To validate the outcomes noted in the MMAC group, we conducted a prospective single-arm clinical trial including 188 patients who underwent CBT with MMAC from 2011 to 2015. Engraftment rate, survival and NRM of the MMAC group in the prospective trail (MMAC-P) were similar to the MMAC group in the retrospective study (MMAC-R). This study is the first to demonstrate the superiority of MMAC to MAC in CBT for hematological malignancies.

European Group for Blood and Marrow Transplantation Risk Score Predicts the Outcome of Patients with Acute Leukemia Receiving Single Umbilical Cord Blood Transplantation.

The European Group for Blood and Marrow Transplantation (EBMT) risk score has been implemented as an important tool to predict patient outcomes after allogeneic hematopoietic stem cell transplantation. However, to our knowledge, this score has never been applied in cases of single umbilical cord blood transplantation (sUCBT). We retrospectively analyzed 207 consecutive patients with acute leukemia who received sUCBT at our center between February 2011 and December 2015. The probabilities of 3-year overall survival (OS) and leukemia-free survival (LFS) of the entire cohort were 65.0% and 59.8%, respectively, whereas the cumulative incidences of 3-year nonrelapse mortality (NRM) and relapse rate were 19.5% and 20.3%, respectively. In the univariate analysis, a higher EBMT risk score was associated with worse OS and LFS and higher NRM and relapse rate, ranging from 81.7%, 75.9%, 7.3%, and 15.3%, respectively, for patients with a score of 1 to 43.8%, 44.3%, 31.7%, and 23.9%, respectively, for patients with scores of 4 to 6. Hazard ratios of OS, LFS, and NRM all steadily increased for each additional score point. Importantly, the prognostic value of the EBMT risk score on OS, LFS, NRM, and relapse was maintained in the multivariate analysis. Moreover, considering the univariate analysis results of donor-recipient gender and mismatched allele-level HLA-A, -B, -C, and -DRB1 loci on patient outcomes and the fairly strong interaction between time from diagnosis to sUCBT and disease status, we developed a modified sUCBT-EBMT risk score by using degrees of 8-allele HLA match instead of donor type, donor-recipient gender combination, and time from diagnosis to sUCBT, and found that the modified score could also be used as a predictor for patient outcomes after sUCBT. The EBMT risk score is a good predictor of outcomes of patients with leukemia after sUCBT. The modified sUCBT-EBMT risk score can also be used as a pretransplant risk assessment, but this metric still requires further evaluation with a larger cohort.

[The curative efficacy of unrelated umbilical cord blood stem cells transplantation in intensified myeloablative conditioned patients with acute lymphoblastic leukemia].

OBJECTIVE: To retrospectively analyze the efficacy of unrelated umbilical cord blood transplantation (UCBT) with intensified myeloablative conditioning regimen in patients with acute lymphoblastic leukemia (ALL). METHODS: From September 2006 to December 2013, a total of 110 consecutive patients with ALL had received UCBT, including 79 male and 31 female patients with a median age of 14(2-51) years, a median weight of 45(12-100)kg. Sixty-one cases were in the first complete remission (CR), 30, 6 and 13 patients in the second, the third CR and advanced stages respectively. The conditioning regimen consisted of total body irradiation, cyclophosphamide and cytarabine (TBI/Cy/Ara-C) in 61 patients, busulfan, cyclophosphamide and fludarabine (BU/Cy/Flu) in 39 patients and BU/Cy/Ara-C in 10 patients. All patients received a combination of cyclosporine (CsA) and mycophenolate mofetil (MMF) for the prophylaxis of graft-versus-host disease (GVHD). RESULTS: The median amount of total nuclear cells(TNC) and CD34(+) cells were 3.90(1.97-13.50)×10(7)/kg and 2.07(0.40-5.56)×10(5)/kg. The cumulative incidence of sustained donor engraftment was 94.5% (95% CI 94.5%-94.6%) at a median of 18 days after transplantation (range, 12-37 days). The cumulative incidence of platelet recovery at 180 days after transplantation was 82.1% (95% CI 81.8%-82.4%) with a median time to recovery of 40 (range, 15-153) days. Incidences of grade Ⅱ~Ⅳ and Ⅲ~Ⅳ acute GVHD were 21.8% and 10.9% respectively. The cumulative incidence of chronic GVHD was 17.9%. During a median follow up period of 26 (range 6-94) months, the disease free survival (DFS) and overall survival (OS) rates at 3 years were 54.5% and 58.8%, respectively. The transplantation-related mortality (TRM) at 180 days after transplantation was 22.7%. The cumulative incidence of 3-year relapse rate was 18.3% (95% CI 17.9%-18.6%). CONCLUSIONS: UCBT with intensified myeloablative conditioning regimen not only improves the donor engraftment, but also shortens the interval of neutrophil and platelet recovery. It is a safe and effective option for children and adult ALL patients lack of matched related donors.

T-cell engager-armed oncolytic vaccinia virus significantly enhances antitumor therapy.

Oncolytic vaccinia virus (VV) therapy has shown promise in preclinical models and in clinical studies. However, complete responses have rarely been observed. This lack of efficacy is most likely due to suboptimal virus spread through the tumor resulting in limited tumor cell destruction. We reasoned that redirecting T cells to the tumor has the potential to improve the antitumor activity of oncolytic VVs. We, therefore, constructed a VV encoding a secretory bispecific T-cell engager consisting of two single- chain variable fragments specific for CD3 and the tumor cell surface antigen EphA2 (EphA2-T-cell engager-armed VV (EphA2-TEA-VV)). In vitro, EphA2-TEA-VV's ability to replicate and induce oncolysis was similar to that of unmodified virus. However, only tumor cells infected with EphA2-TEA-VV induced T-cell activation as judged by the secretion of interferon-γ and interleukin-2. In coculture assays, EphA2-TEA-VV not only killed infected tumor cells, but in the presence of T cells, it also induced bystander killing of noninfected tumor cells. In vivo, EphA2-TEA-VV plus T cells had potent antitumor activity in comparison with control VV plus T cells in a lung cancer xenograft model. Thus, arming oncolytic VVs with T-cell engagers may represent a promising approach to improve oncolytic virus therapy.

Structural insights into the calcium-coupled zinc export of human ZnT1.

Cellular zinc (Zn2+) homeostasis is essential to human health and is under tight regulations. Human zinc transporter 1 (hZnT1) is a plasma membrane-localized Zn2+ exporter belonging to the ZnT family, and its functional aberration is associated with multiple diseases. Here, we show that hZnT1 works as a Zn2+/Ca2+ exchanger. We determine the structure of hZnT1 using cryo-electron microscopy (cryo-EM) single particle analysis. hZnT1 adopts a homodimeric structure, and each subunit contains a transmembrane domain consisting of six transmembrane segments, a cytosolic domain, and an extracellular domain. The transmembrane region displays an outward-facing conformation. On the basis of structural and functional analysis, we propose a model for the hZnT1-mediated Zn2+/Ca2+ exchange. Together, these results facilitate our understanding of the biological functions of hZnT1 and provide a basis for further investigations of the ZnT family transporters.

Unrelated cord blood transplantation for central nervous system relapse in high-risk childhood acute lymphoblastic leukemia.

Few clinical studies have investigated the role of unrelated cord blood transplantation (CBT) for central nervous system (CNS) relapse of childhood acute lymphoblastic leukemia (ALL) patients with high-risk factors. The aim of this report is to identify the potential benefits of unrelated CBT in high-risk childhood ALL with CNS relapse who has been treated on CNS-directed treatment strategies. Eleven childhood ALL patients with CNS relapse who underwent unrelated CBT enrolled in our study between 2001 and 2011, and all of the patients had features associated with poor outcomes, such as high white blood cells at diagnosis, ph + chromosome, or a history of bone marrow relapse. All transplants were performed with myeloablative-conditioning therapy (BU/cyclophosphamide (CY2) or total body irradiation/CY) plus highly CNS-active agents (carmustine or high-dose cytarabine). All patients achieved neutrophil engraftment and platelet engraftment. A total of nine patients (81.8 %) developed pre-engraftment syndrome at a median of 7 days, and three patients developed acute graft-vs-host disease at a median of 21 days. The median follow-up after CBT was 28.5 months. The probability of overall survival at 9 years was 63.6 %, and no patient experienced a CNS relapse. Our experience suggests that unrelated CBT appears to be an effective treatment option for CNS relapse of childhood ALL patients associated with poor outcome features.

Toll-like receptors 2 and 4 mediate the capacity of mesenchymal stromal cells to support the proliferation and differentiation of CD34⁺ cells.

Bone marrow derived-mesenchymal stromal cells (BM-MSCs) are multipotent, nonhematopoietic progenitors in a hematopoietic microenvironment and indispensable for regulating hematopoiesis. Several studies have reported that toll-like receptors (TLRs) are expressed in mesenchymal stromal cells (MSCs) to modulate their biological functions. In this study, we investigated the possible role(s) of TLRs in mediating the hematopoiesis-supporting role of human BM-MSCs. Human BM-MSCs were analyzed for mRNA expression of TLR1-10 by reverse transcription-polymerase chain reaction. TLR1-6, but not TLR7-10 were expressed by BM-MSCs. The protein expression of TLR2 and TLR4 was also confirmed by flow cytometry. We further explored the role of TLR2 and TLR4 in mediating the capacity of BM-MSCs to support the proliferation and differentiation of CD34(+) hematopoietic stem/progenitor cells obtained from cord blood. BM-MSCs increased proliferation of CD34(+) cells and promoted the differentiation towards the myeloid lineage 7 or 14days after co-culture, as well as colony formation by those cells and the production of interleukin 1 (IL-1), IL-8, IL-11, stem cell factor (SCF), granulocyte colony-stimulating factor (CSF), macrophage CSF and granulocyte-macrophage CSF, if MSCs had been stimulated with TLR2 agonist (PAM(3)CSK(4)) or TLR4 agonist (LPS). Interestingly, although these effects were elevated in a different degree, a synergistic effect was not observed in BM-MSCs co-stimulated with PAM(3)CSK(4) and LPS. Together, our findings suggest that TLR2 and TLR4 signaling may indirectly regulate hematopoiesis by modulating BM-MSCs' functions. The increased hematopoietic proliferation and differentiation could be mediated, at least in part, by augmented hematopoiesis-related cytokine production of BM-MSCs.

WPD-Enhanced Deep Graph Contrastive Learning Data Fusion for Fault Diagnosis of Rolling Bearing.

Rolling bearings are crucial mechanical components in the mechanical industry. Timely intervention and diagnosis of system faults are essential for reducing economic losses and ensuring product productivity. To further enhance the exploration of unlabeled time-series data and conduct a more comprehensive analysis of rolling bearing fault information, this paper proposes a fault diagnosis technique for rolling bearings based on graph node-level fault information extracted from 1D vibration signals. In this technique, 10 categories of 1D vibration signals from rolling bearings are sampled using a sliding window approach. The sampled data is then subjected to wavelet packet decomposition (WPD), and the wavelet energy from the final layer of the four-level WPD decomposition in each frequency band is used as the node feature. The weights of edges between nodes are calculated using the Pearson correlation coefficient (PCC) to construct a node graph that describes the feature information of rolling bearings under different health conditions. Data augmentation of the node graph in the dataset is performed by randomly adding nodes and edges. The graph convolutional neural network (GCN) is employed to encode the augmented node graph representation, and deep graph contrastive learning (DGCL) is utilized for the pre-training and classification of the node graph. Experimental results demonstrate that this method outperforms contrastive learning-based fault diagnosis methods for rolling bearings and enables rapid fault diagnosis, thus ensuring the normal operation of mechanical systems. The proposed WPDPCC-DGCL method offers two advantages: (1) the flexibility of wavelet packet decomposition in handling non-smooth vibration signals and combining it with the powerful multi-scale feature encoding capability of GCN for richer characterization of fault information, and (2) the construction of graph node-level fault samples to effectively capture underlying fault information. The experimental results demonstrate the superiority of this method in rolling bearing fault diagnosis over contrastive learning-based approaches, enabling fast and accurate fault diagnoses for rolling bearings and ensuring the normal operation of mechanical systems.

Outcomes of Second Anti-CD19 CAR T-Cell Therapy (CART2) in Acute B Lymphoblastic Leukemia and the Impact of Allo-HSCT on Efficacy.

For patients exhibiting a suboptimal response to the first chimeric antigen receptor (CAR) T-cell therapy (CART1) or relapse after remission, secondary CAR T-cell therapy (CART2) for the same target may be an option. We retrospectively analyzed patients with acute B-cell lymphoblastic leukemia (B-ALL) receiving CD19 CART1 at our center (n = 84) to report the clinical outcomes of CART2 and to identify the factors that may influence the outcomes. Twenty-six patients received CART2 for suboptimal response or relapse post-CART1. The incidence of cytokine release syndrome (CRS) after CART2 was 65.4% (17/26), with 11 cases classified as grade 1 (42.3%), four cases as grade 2 (15.4%), and two cases as grade 3 (7.7%). Neurotoxicity was observed in one patient (3.8%) after CART2 infusion. Fourteen patients (53.8%) achieved complete remission (CR) after CART2. CART2 exhibited an inferior response rate (CART2: 53.8%, 14/26; CART1: 81.0%, 64/79; P = 0.006) and a lower incidence of severe CRS (CART2: 7.7%, 2/26; CART1: 30.4%, 24/79; P = 0.020) compared with CART1, with a median progression-free survival (PFS) and a median overall survival (OS) of 6.2 months and 11.2 months, respectively. In particular, patients who progressed after consolidative allogeneic hematopoietic stem cell transplantation (allo-HSCT) following CART1 and then received CART2 demonstrated promising outcomes with a response rate of 80.0% (8/10), a median PFS of 7.9 months, and a median OS of 25.1 months. After adjusting for the confounding factors, the response rate (85.7%, 6/7) of CART2 administered to this cohort was better than those who did not bridge to allo-HSCT receiving CART2 (28.6%, 2/7) or non-CART2 treatments (13.3%, 2/15). The median OS after CART2, which was not reached, was significantly better than the median OS after CART2 (3.9 months, P = 0.014) and non-CART2 treatments (6.0 months, P = 0.012) administered in patients who did not undergo consolidative allo-HSCT post-CART1. Our results indicated that, although less effective than CART1, a subset of patients can still benefit from CART2 with mild adverse effects. For patients who relapsed after consolidative allo-HSCT post-CART1, treatment with CART2 is a viable option.

Pre-engraftment syndrome after unrelated donor umbilical cord blood transplantation in patients with hematologic malignancies.

Pre-engraftment syndrome (PES) after umbilical cord blood transplantation (CBT) remains poorly characterized, and the prognosis and appropriate management are unclear. Therefore, we retrospectively analyzed the incidence, risk factors, manifestations, and clinical outcomes of PES in CBT recipients, who had been treated for hematologic malignancies at our transplantation center. PES was defined as unexplained fever higher than 38.3°C that is not associated with documented infection and unresponsive to antimicrobial manipulations and/or unexplained erythematous skin rash occurring prior to neutrophil engraftment. A total of 81 patients (median 18 yr, range 3-48) received either myeloablative (n=72) or non-myeloablative (n=9) conditioning. Neutrophil engraftment was achieved in 69 of the 81 cases [86.2%, 95% confidence interval (CI)=78.9-94.1%], and the median time to more than 0.5 × 10(9) /L ANC was 19 d (range, 12-39). Fifty-one patients (63.0%) developed PES at a median of 7d (range 3-15) post-transplant: 46 patients had both rash and unexplained fever; one patient had unexplained fever alone; and four patients had rash only. Forty-seven patients (92.2%) received IV methylprednisolone (MP) at a median dose of 1 mg/kg (range 0.4-3). All patients treated with MP responded as evidenced by fever resolution combined with resolution of rash. All patients with PES had high serum levels of C-reactive protein (CRP), which were significantly reduced after effective steroid treatment. Univariate analysis identified myeloablative conditioning and younger age as significant risk factors for developing PES. Cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD) in the PES+ and PES- groups was 51.5% (95% CI=38.0-70.0%) and 17.0% (95% CI=6.9-41.7%), respectively. In a multivariate analysis, we found significantly increased risk of grade II-IV aGVHD among PES patients (P=0.041). However, PES was not associated with sustained donor engraftment, the day to neutrophil recovery, chronic graft-versus-host disease, transplant-related mortality at day 180, and overall survival. Despite of the inherent limitations of this small retrospective study, PES seemed to be common after CBT and associated with high incidence of aGVHD.

[Unrelated umbilical cord blood transplantation with TBI/Ara-c/CY non-ATG conditioning regimen for adults with hematologic malignancies].

OBJECTIVE: To retrospectively analyze the curative efficacy of umbilical cord blood transplantation (UCBT) with improved myeloablative conditioning regimen (total body irradiation (TBI)/cytosine arabinoside (Ara-c)/cyclophosphamide (CY) without antithymocyte globulin (ATG)) in adult patients with hematological malignancies. METHODS: Forty consecutive adult patients with hematological malignancies received improved myeloablative unrelated CBT at a single center from September 2006 to May 2011. Their average age was (23 ± 6) years and the average weight (58 ± 9) kg. Thirty-five (87.5%) patients were high-risk and 15 (37.5%) at the advanced disease status at pre-transplantation. They received 1 (n = 23) or 2 (n = 17) cord blood units. Seventy-five percent of them were transplanted with 1/2-human leukocyte antigen mismatched unit. The conditioning regimen consisted of 12 Gy TBI, granulocyte colony-stimulating factor (G-CSF) plus Ara-c and CY without ATG. All patients received a combination of cyclosporine (CsA) and mycophenolate mofetil (MMF) for the prophylaxis of graft-versus-host disease (GVHD). RESULTS: For the entire group of patients, the average cell doses infused were (4.1 ± 1.1)×107 total nucleated cells/kg and (2.4 ± 1.0)×105 CD34(+) cells/kg. All patients acquired engraftment with an implantation rate of 100%. The average time of absolute neutrophil count (ANC) ≥ 0.5×109/L was (20 ± 5) days and the average time of platelet ≥ 20×109/L was(38 ± 12) days. Acute GVHD occurred in 23 patients (57.5%) and 4 (10.0%) were of grade III-IV. Chronic GVHD occurred in 22.9% (8/35) evaluable patients. Relapse occurred in 12.5% (5/40) patients. During a median follow-up period of 19.8 (range 4.6 - 55.0) months, the transplantation-related mortality was 15.0% (6/40) within 100 days and 35.0% (14/40) within 1 year. The main causes of mortality were pneumonia and severe acute GVHD. Two-year overall survival (OS) or disease-free survival was 58.8% and 58.8%, respectively. Two-year OS for patients with advanced or complete remission disease was 48.6% and 63.8%, respectively. CONCLUSIONS: The TBI/Ara-c/CY myeloablative conditioning regimen is well-tolerated and capable of establishing sustained donor cell engraftment and decreasing the risks of transplant-related death in adults with hematologic malignancies. For the high-risk and advanced patients, it may reduce the occurrences of relapse and chronic GVHD.

[Clinical Study on Dynamic Detection of Minimal Residual Disease in Acute Myeloid Leukemia by Multiparameter Flow Cytometry].

OBJECTIVE: To investigate the prognostic significance of dynamic detection of minimal residual disease (MRD) in patients with acute myeloid leukemia (AML) by 8-color flow cytometry. METHODS: MRD of 282 AML patients who achieved remission after initial therapy was detected by 8-color flow cytometry. MRD threshold for predicting recurrence was determined by receiver operating characteristic (ROC) curve, and time from MRD-positive to clinical recurrence was analyzed. The differences in overall survival (OS) time and relapse-free survival (RFS) time of patients with different MRD-changes were compared, and the related factors of recurrence in patients with MRD-negative were analyzed by univariate and logistic regression analysis. RESULTS: ROC curve determined that the MFC-MRD threshold for predicting the recurrence of AML was 0.105%, and the recurrence rate of MRD-positive patients was significantly higher than that of MRD-negative patients [52.45% (75/143 cases) vs 35.97% (50/139 cases), P=0.005]. The patients in MRD persistent positive group and negative to positive group recurred earlier than those in positive to negative group and negative-positive fluctuation group (P<0.005). Survival analysis showed that OS and RFS time of patients with MRD persistent positive were significantly shorter than those of patients with MRD persistent negative, positive to negative, and negative-positive fluctuation (P<0.005). There was no significant difference in OS and RFS between MRD negative to positive group and MRD persistent positive group (P>0.005), either between MRD persistent negative group and MRD positive to negative group (P>0.005). Among 139 MRD-negative patients, 50 recurred. Univariate and logistic regression analysis showed that the risk of recurrence increased with the increase of white blood cells level (95%CI: 1.000-1.013, P=0.045). The risk of recurrence in patients without hematopoietic stem cell transplantation (HSCT) was 9.694 times higher than that in patients who received HSCT (95%CI: 1.720-54.651, P=0.010), and in the high-risk group was 5.848 times higher than that in the low-risk group (95%CI: 1.418-24.121, P=0.015). CONCLUSION: The prognosis of AML patients with different MRD changes is significantly different. No matter MRD-positive or MRD-negative at the initial remission, dynamic detection of MRD after treatment is more helpful to accurately guide treatment.

Zkscan3 affects erythroblast development by regulating the transcriptional activity of GATA1 and KLF1 in mice.

ZKSCAN3 encodes a zinc-finger transcription factor that regulates the expression of important genes and plays a significant role in tumor development, pathogenesis, and metastasis. However, its biological functions under normal physiological conditions remain largely unknown. In our previous studies, using flow cytometry, we found that the deletion of Zkscan3 may cause abnormal erythropoiesis. In this study, we found that, in a Zkscan3 knockout mice model, the number of splenic early-stage (basophilic-erythroblasts) and late-stage (chromatophilic-erythroblasts to polychromatophilic-erythroblasts through orthochromatophilic-erythroblasts) erythroblasts increased, whereas the number of late erythroblasts in the bone marrow decreased. Moreover, the phenotype was exacerbated after treating mice with phenylhydrazine (PHZ), which causes severe hemolytic anemia. In the knockout mice treated with PHZ, the percentage of reticulocyte in the peripheral blood conspicuously increased, whereas MCHC and red blood cells decreased. Then, we performed RNA-seq and quantitative-polymerase chain reaction assay and found that the expression of GATA1 and Tiam1 in erythroblasts were upregulated, whereas KLF1 was downregulated. Luciferase assays showed that Zkscan3 inhibited the transcription of GATA1 and Tiam1 and promoted the expression of KLF1. Additionally, ChIP and CO-IP results confirmed that Zkscan3 directly interacts with GATA1 and inhibits its transcriptional activity in MEL cells. Our results demonstrate, for the first time, the significant role of Zkscan3 in physiological erythropoiesis through the interaction with GATA1, both at the DNA and protein level, and with Tiam1 and KLF1 at the DNA level.

Impact of Consolidative Unrelated Cord Blood Transplantation on Clinical Outcomes of Patients With Relapsed/Refractory Acute B Lymphoblastic Leukemia Entering Remission Following CD19 Chimeric Antigen Receptor T Cells.

Background: While chimeric antigen receptor (CAR)-T cell therapy is becoming widely used in hematological malignancies with remarkable remission rate, their high recurrence remains an obstacle to overcome. The role of consolidative transplantation following CAR-T cell-mediated remission remains controversial. We conducted a retrospective study to explore whether bridging to unrelated cord blood transplantation (UCBT) could improve the prognosis of patients entering remission after CAR-T therapy with different characteristics through subgroup analyses. Methods: We reviewed 53 patients with relapsed/refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL) successfully infused with CD19 CAR-T cells and achieved complete remission (CR). In this study, 25 patients received consolidative UCBT (UCBT group) and 28 patients did not accept any intervention until relapse (non-UCBT group). Subgroup analysis on prognosis was then performed according to gender, age, number of previous relapses, tumor burden, presence of poor prognostic markers, and structure of CAR. Results: Compared with the non-UCBT group, patients who underwent consolidative UCBT had better median event-free survival (EFS; 12.3 months vs. 6.2 months; P = 0.035) and relapse-free survival (RFS; 22.3 months vs. 7.2 months; P = 0.046), while no significant difference was found in overall survival (OS; 30.8 months vs. 15.3 months; P = 0.118). Subsequent multivariate analysis revealed that bridging to UCBT was a protective factor for RFS (P = 0.048) but had no significant effect on EFS (P = 0.205) or OS (P = 0.541). In the subgroup analysis, UCBT has an added benefit in patients with specific characteristics. Patients who experienced ≥2 relapses or with sustained non-remission (NR) showed better RFS (P = 0.025) after UCBT. Better EFS was seen in patients with poor prognostic markers (P = 0.027). In the subgroup with pre-infusion minimal residual disease (MRD) ≥5% or with extramedullary disease (EMD), UCBT significantly prolonged EFS (P = 0.009), RFS (P = 0.017), and OS (P = 0.026). Patients with occurrence of acute graft-versus-host disease (aGVHD) appeared to have a longer duration of remission (P = 0.007). Conclusion: Consolidative UCBT can, to some extent, improve clinical outcomes of patients with R/R B-ALL entering remission following CD19 CAR-T therapy, especially in patients with more recurrences before treatment, patients with poor prognostic markers, and patients with a higher tumor burden. The occurrence of aGVHD after UCBT was associated with better RFS.

Standard-Intensity Induction and Intermediate/High-Dose Cytarabine Consolidation Can Improve Survival for Elderly Patients with Newly Diagnosed Acute Myeloid Leukemia: A Retrospective Cohort Study.

BACKGROUND: There is great uncertainty in the treatment of elderly patients with acute myeloid leukemia (AML), which leads to great challenges in treatment decision. The aim of this study is to find more suitable induction therapy and consolidation therapy for elderly AML patients. METHODS: A total of 149 consecutive newly diagnosed elderly AML patients (aged ≥60 years) who received induction chemotherapy in our medical center from January 2015 to December 2019 were retrospectively analyzed. RESULTS: After the first induction treatment, the complete remission/or complete remission with incomplete hematologic recovery (CR/CRi) rates in the standard-intensity chemotherapy group was significantly higher than that in the low-intensity chemotherapy group (58.2% vs 32.9%, p = 0.003). Compared with the low-intensity chemotherapy, the incidence of severe infection in the standard-intensity chemotherapy was significantly increased (p < 0.001), but the early mortality was comparable. One hundred and seven patients received minimal residual disease (MRD) examination after the first induction treatment; and MRD was negative accounting for 51.9% in the standard-intensity chemotherapy group, while only 32.7% in the low-intensity group (p = 0.05). The 2-year-overall survival (OS) of patients in standard-intensity induction chemotherapy group (37.2%) was slightly higher than that in low-intensity induction chemotherapy group (23.4%) (p = 0.075). Eighty-one CR/CRi patients received intermediate or high dose cytarabine (n = 35) or sequential chemotherapy regimens (n = 46) as consolidation treatment. The 2-year OS and event-free survival (EFS) of patients in the intermediate or high-dose cytarabine group were significantly higher than those in the sequential chemotherapy regimens group (73.0% vs 38.5%, p = 0.002; 54.8% vs 35.0%, p = 0.035). CONCLUSION: Our results showed that standard-intensity induction chemotherapy can significantly improve the CR rate for elderly AML patients, and does not increase the early mortality; consolidation therapy with intermediate or high-dose cytarabine can significantly improve EFS and OS for elderly AML patients achieved CR.