Advances in the ocular complications after hematopoietic stem cell transplantation.

Hematopoietic stem cell transplantation (HSCT) has benefited an increasing number of patients with hematological disease in the clinic. It is a curative therapy for malignant and nonmalignant hematological diseases. With the advancement and further clinical application of HSCT in recent years, the life expectancy of patients has increased, but complications have become more common. The occurrence of ocular complications is receiving increasing attention because they can seriously affect the quality of life of patients. Ocular complications require increased attention from clinicians because of their negative impact on patients and increasing incidence. Most of recent reports on posttransplant ocular complications involve ocular manifestations of graft-versus-host disease (GVHD), and a few ocular complications that do not originate from GVHD have also been reported. This review summarizes the diagnosis, scoring criteria, pathophysiology, and clinical manifestations of and common therapies for ocular graft-versus-host disease(oGVHD) after HSCT, and includes a description of some rare cases and novel therapies.

SET-CAN/NUP214 fusion gene in leukemia: general features and clinical advances.

SET-CAN/NUP214 fusion is a recurrent event commonly observed in adult male patients diagnosed with T-cell acute lymphoblastic leukemia (T-ALL) and has occasionally been reported in other diseases such as acute myeloid leukemia (AML), myeloid sarcoma (MS), acute undifferentiated leukemia (AUL), chronic myeloid leukemia (CML) and B-cell acute lymphoblastic leukemia (B-ALL). This fusion gene is derived from chromosome del(9)(q34.11;q34.13) or t(9;9)(q34;q34) and may have an inhibitory effect on primitive progenitor differentiation. The prognosis of the reported patients is varied, with these patients often show resistance to chemotherapy regimens that include high doses of glucocorticoids. The optional treatment has not been determined, more cases need to be accumulated and evaluated. The scope of this review is to summarize the general features and prognostic significance in leukemia associated with the SET-CAN/NUP214 fusion gene and to discuss the methods of detection and treatment, aiming at providing some useful references for relevant researchers in the field of blood tumor.

A New Scoring System for Predicting Mortality in Hematological Malignancies with Sepsis: A Derivation and Validation Study.

Objective: This study aimed to derive and validate a prognostic scoring system to identify patients with hematological malignancies (HMs) and sepsis who have a high mortality rate. Methods: Cohorts for derivation and validation were created from all data. Using univariate and multivariate analysis, the independent variables connected to 28-day mortality in the derivation cohort were found. A receiver operating characteristic (ROC) curve was used to compare the predictive power and determine their cutoff points. These risk variables were given a score weighted by risk prediction function, and a new scoring system was also developed. The area under the ROC curve (AUROC) and sensitivity and specificity for mortality of the risk category of the new scoring system were compared with Sequential Organ Failure Assessment (SOFA) score. Results: 90 (45.22%) of the 199 patients passed away within 28 days. Ninety-nine patients made up the derivation cohort, with 47 (47.47%) fatalities. Ages in the non-survival group were higher (61.47 ± 14.53 vs 55.13 ± 15.66) than in the survival group. As independent predictors of death, multivariable analysis identified SOFA score (OR 1.442, 95% CI 1.035, 2.009), age (OR 1.242, 95% CI 1.026, 1.503), and prothrombin time (PT) (OR 1.213, 95% CI 1.030, 1.430). The AUROC with 95% CI of the new scoring system and its sensitivity and specificity to mortality were virtually all superior to SOFA score in both derivation and validation cohorts: AUROC (0.757 vs 0.716), Sensitivity (75 vs 67.3%), and Specificity (68.1% vs 63.8%) are the Derivation cohort; Validation cohort: Sensitivity (91.2% vs 84.2%), AUROC (0.792 vs 0.733), and Specificity (58.1% vs 58.1%). The model was correctly calibrated, according to the Hosmer-Lemeshow test. Conclusion: The new scoring system was more accurate in predicting 28-day mortality among patients with HMs and sepsis than the SOFA score.

miR-603 promotes cell proliferation and differentiation by targeting TrkB in acute promyelocytic leukemia.

Arsenic trioxide (ATO) treatment effectively prolongs the overall survival of patients with acute promyelocytic leukemia (APL). Mutations in the oncogene PML::RARA were found in patients with ATO-resistant and relapsed APL. However, some relapsed patients do not have such mutations. Here, we performed microarray analysis of samples from newly diagnosed and relapsed APL, and found different microRNA (miRNA) expression patterns between these two groups. Among the differentially expressed miRNAs, miR-603 was expressed at the lowest level in relapsed patients. The expression of miR-603 and its predicted target tropomyosin-related kinase B (TrkB) were determined by PCR and Western blot. Proliferation was measured using an MTT assay, while apoptosis, cell cycle and CD11b expression were analyzed using flow cytometry. In APL patients, the expression of miR-603 was negatively correlated with that of TrkB. miR-603 directly targeted TrkB and downregulated TrkB expression in the APL cell line NB4. miR-603 increased cell proliferation by promoting the differentiation and inhibiting the apoptosis of NB4 cells. This study shows that the miR-603/ TrkB axis may be a potent therapeutic target for relapsed APL.

Single-Center Retrospective Clinical Evaluation of Venetoclax Combined with HMAs and Half-Dose CAG for Unfit or Refractory/Relapsed AML.

Purpose: The prognosis of patients with unfit or relapsed/refractory (R/R) AML remains poor. Venetoclax (VEN) has been shown to exhibit anti-leukemia stem cell activity; however, few studies have been published on the efficacy and safety of VEN combined with both hypomethylating agents (HMAs) and low-dose chemotherapy for patients with unfit or R/R AML. Methods: This study retrospectively analyzed the clinical characteristics, treatment details, safety profile and clinical outcomes of patients with unfit or R/R AML treated with VEN+ HMAs+ half-dose CAG (LDAC, aclarubicin and granulocyte colony-stimulating factor). Results: A total of 24 AML patients were involved in the study, of whom 13 (54.2%) were in the unfit group, and 11 (45.8%) were in the R/R group. FLT3 and IDH (8/24, 33.3%) were the most common gene aberrations. Patients in the R/R group were found to be more likely to carry KIT (5/11, 45.5%) compared with the unfit group (0/13, 0%) (P = 0.006). The ORR observed during the study was 83.3% (20/24; 14 CR, 2CRi, 4PR). In the unfit group, 11/13 (84.6%) patients achieved cCR (10 CR and 1 CRi); while 5/11 (45.5%) R/R patients achieved response (4 CR and 1 CRi). CR was observed in all AML patients with TP53 (5/5), GATA2 (3/3), CEBPA (3/3) and ASXL1 (3/3). The most common adverse events (AEs) during VEN+ HMAs+ half-dose CAG therapy were persistent cytopenias and infections. Conclusion: The results of this study confirm that VEN+ HMAs+ half-dose CAG is associated with promising efficacy (even high-risk molecular patterns) and tolerable safety profile in patients with unfit or R/R AML. Yet, the study involves only a small sample size, which should not be overlooked. As such, further studies on the efficacy of VEN combined with HMAs and half-dose CAG regimen in AML patients are essential.

Efficacy and safety of an HDACi- and HMA-based protocol in adults with acute myeloid leukemia of intermediate- and adverse-risk categories: a retrospective study.

OBJECTIVE: Anthracyclines and cytarabine have comprised standard induction therapy for acute myeloid leukemia (AML) for decades. Low overall survival of AML is due to non-remission or relapse after remission. Hypomethylating agent (HMA) decitabine combined with low-dose chemotherapy or other targeted agents has shown promising effect for AML in clinical trials, especially in t(8;21) acute myeloid leukemia. We previously investigated histone deacetylase inhibitor (HDACi) chidamide could regulate Wnt/ß-catenin signaling pathway in leukemia cell lines. METHODS: Adult patients with de novo or relapsed/refractory AML who were treated with chidamide and decitabine in combination with chemotherapy (chidamide group, n = 23) or only decitabine combination with chemotherapy (decitabine group, n = 17) were analyzed. RESULTS: Chidamide group represented higher complete response rate (82.6% and 52.9%, p = 0.0430, vs. decitabine group), progression-free survival and overall survival rates (p = 0.0088 and p = 0.0139, respectively), especially for patients with de novo AML. Hematological toxicity and infections were the most common adverse events (AEs) in both groups, and they were manageable by supportive treatments. CONCLUSIONS: This HDACi- and HMA-based protocol is an effective and tolerable therapy for patients with AML. The comprehensive mechanism and effects of chidamide in combination with decitabine are worth to be further explored in AML.

The novel HLA-C*15:02:58 allele, identified by Sanger dideoxy nucleotide sequencing in a Chinese individual.

HLA-C*15:02:58 differs from HLA-C*15:02:01:01 by one nucleotide in exon 1.

Targeting FHL1 impairs cell proliferation and differentiation of acute myeloid leukemia cells.

The four and a half LIM domains 1 (FHL1) is considered to play important roles in tumors. This study aims to investigate the role and precise mechanisms of FHL1 in acute myeloid leukemia (AML). Here, we found that FHL1 was highly expressed in AML. CCK8, flow cytometry, and Western blot analysis of cell cycle-related proteins showed that overexpression of FHL1 promoted proliferation and accelerated cell cycle progression in HL-60 cells. Conversely, knockdown of FHL1 inhibited the proliferation and induced cell cycle arrest in KG-1 cells. Furthermore, knockdown of FHL1 promoted cell differentiation, while overexpression of FHL1 restrained all-trans retinoic acid induced cell differentiation in HL-60 cells, revealed by Wright-Giemsa staining and cell surface antigen analysis. Moreover, in vivo experiments revealed that depletion of FHL1 inhibited tumor growth and led to increased levels of CD11b and CD14. Here, we first identify an unexpected and important role of FHL1 that contributes to the AML progression, indicating that FHL1 may be a potential therapeutic target for AML.

Clinical Characteristics and Outcome Analysis for HLA Loss Patients Following Partially Mismatched Related Donor Transplantation Using HLA Chimerism for Loss of Heterozygosity Analysis by Next-Generation Sequencing.

Genomic loss of mismatched human leukocyte antigen (HLA loss) is one of the most vital immune escape mechanisms of leukemic cells after allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, the methods currently used for HLA loss analysis have some shortcomings. Limited literature has been published, especially in lymphoid malignancies. This study aims to evaluate the incidences, risk factors of HLA loss, and clinical outcomes of HLA loss patients. In all, 160 patients undergoing partially mismatched related donor (MMRD) transplantation from 18 centers in China were selected for HLA loss analysis with the next-generation sequencing (NGS)-based method, which was validated by HLA-KMR. Variables of the prognostic risk factors for HLA loss or HLA loss-related relapse were identified with the logistic regression or the Fine and Gray regression model. An HLA loss detection system, HLA-CLN [HLA chimerism for loss of heterozygosity (LOH) analysis by NGS], was successfully developed. Forty (25.0%) patients with HLA loss were reported, including 27 with myeloid and 13 with lymphoid malignancies. Surprisingly, 6 of those 40 patients did not relapse. The 2-year cumulative incidences of HLA loss (22.7% vs 22.0%, P = 0.731) and HLA loss-related relapse (18.4% vs 20.0%, P = 0.616) were similar between patients with myeloid and lymphoid malignancies. The number of HLA mismatches (5/10 vs <5/10) was significantly associated with HLA loss in the whole cohort [odds ratio (OR): 3.15, P = 0.021] and patients with myeloid malignancies (OR: 3.94, P = 0.021). A higher refined-disease risk index (OR: 6.91, P = 0.033) and donor-recipient ABO incompatibility (OR: 4.58, P = 0.057) contributed to HLA loss in lymphoid malignancies. To sum up, HLA-CLN could overcome the limitations of HLA-KMR and achieve a better HLA coverage for more patients. The clinical characteristics and outcomes were similar in patients with HLA loss between myeloid and lymphoid malignancies. In addition, the results suggested that a patient with HLA loss might not always relapse.

Loss of mismatched HLA in acute myeloid leukemia relapse after haploidentical peripheral blood stem cell transplantation combined with unrelated cord blood: A case report.

Mismatched human leukocyte antigen (HLA) loss is an essential mechanism involved in immune escape and recurrence in acute leukemia after haploidentical transplantation. Patients relapsing after transplantation with HLA loss have a poor prognosis, and are less likely to benefit from donor lymphocyte infusion (DLI) from the original donor. Here, we report a patient with high-risk acute myeloid leukemia who relapsed within six months after haploidentical peripheral blood stem cell transplantation (PBSCT) combined with unrelated umbilical cord blood (UCB) with a session of prophylactic DLI. This patient achieved transient remission after subsequent Interferon-α-1b treatment for two weeks but experienced a second relapse within one month. Genomic analysis by real-time PCR assay revealed that this patient had a loss of an entire mismatched HLA haplotype that was derived from her haploidentical donor. Haploidentical peripheral blood stem cell transplantation with prophylactic DLI might be a triggering event for HLA loss relapse after haploidentical transplantation combined with UCB. HLA loss should be considered in patients with post-HSCT relapse, especially in haploidentical transplantation.

Pharmacokinetics of cefoperazone/sulbactam in critically Ill thrombotic thrombocytopenic purpura patients undergoing therapeutic plasma exchange.

WHAT IS KNOWN AND OBJECTIVES: The aim of this study was to investigate the pharmacokinetics (PK) of cefoperazone (CFP) and sulbactam (SUL) in critically ill thrombotic thrombocytopenic purpura (TTP) patients undergoing therapeutic plasma exchange (TPE). METHODS: Critically ill TTP patients receiving a dose of 3 g CFP/SUL (2.0 g/1.0 g) intravenously every 8 h were included in the study. TPE session began 10 min after the end of CFP/SUL infusion. Serial blood samples were collected at 0, 1, 2, 3, 4, 6 and 8 h at the fourth infusion with TPE and the sixth infusion without TPE. Effluent samples were collected at the effluent port of plasma eliminated at the end of TPE. Concentrations of CFP and SUL in plasma and effluent were measured using LC-MS/MS. PK parameters were calculated based on two-compartment open model. RESULTS: Five critically ill TTP patients receiving CFP/SUL monotherapy were enrolled. T1/2α of CFP and SUL with TPE was 0.62 and 1.30 h, respectively. For CFP, T1/2ß with TPE were significantly higher than those without TPE (5.85 ± 3.16 vs. 4.41 ± 2.74, p = 0.016). Vss with TPE were significantly higher than those without TPE (7.23 ± 0.89 vs. 5.24 ± 0.80 L, p = 0.024). AUC0-8 with TPE were significantly lower compared with those without TPE (1380.98 ± 411.99 vs. 1581.61 ± 500.22 mg*h/L, p = 0.011). Relatively, CLt with TPE were significantly higher than those without TPE (1.56 ± 0.46 vs. 1.37 ± 0.44 L/h, p = 0.010). For SUL, Vss and CLt were higher significantly with TPE than those without TPE (28.11 ± 8.42 vs. 18.87 ± 6.45 L, p = 0.002; 10.74 ± 2.01 vs. 8.60 ± 2.10 L/h, p = 0.048). Mean QPE of CFP and SUL were 344.42 ± 55.37 and 34.65 ± 10.09 mg, respectively. Mean fe% of CFP and SUL were 17.22 ± 2.77% and 3.46 ± 1.01%, respectively. WHAT IS NEW AND CONCLUSION: TPE enhances the clearance of CFP and SUL in critically ill TTP patients. CFP is more likely to be removed than SUL due to its a low V and high Pb. TPE is suggested to begin 1-2 h after the end of CFP/SUL infusion. Plasma concentration monitoring is advised when CFP/SUL must be administered during TPE.

Knockdown of ADORA2A antisense RNA 1 inhibits cell proliferation and enhances imatinib sensitivity in chronic myeloid leukemia.

Long non-coding RNAs (LncRNAs) exert important regulatory roles in chronic myeloid leukemia (CML). In this study, we aimed to investigate the potential role and molecular mechanism of lncRNA ADORA2A antisense RNA 1 (ADORA2A-AS1) in CML. We found that the expression of ADORA2A-AS1 was upregulated in CML. Further, knockdown of ADORA2A-AS1 inhibited the proliferation, induced apoptosis, arrested cell cycle, and enhanced imatinib sensitivity in CML cells. Besides, ADORA2A-AS1 promoted the expression of transforming growth factor-beta receptor 1 (TGFBR1) and ATP binding cassette subfamily C member 2 (ABCC2) via sponging miR-665, thereby exerting a tumor-promoting activity. Collectively, our results confirmed the oncogenic effect of ADORA2A-AS1 in CML, indicating that ADORA2A-AS1 is a promosing therapeutic target for CML.

Gene mutations in acute promyelocytic leukemia early death in patients treated with arsenic trioxide alone

Purpose APL patients have recurrent alterations in FLT3, WT1, NRAS and KRAS. Gene mutations have a strong potential for involvement in pathogenesis and may have potential effects on the clinical manifestations. Gene mutations may even be associated with early death (ED) in APL patients. However, there is little published information on mutations in APL patients and whether they are attributed to early death. Methods In this study, we retrospectively analyzed the clinical data and gene mutations of 134 de novo APL patients. We detected the gene mutations by next-generation sequencing (NGS) to investigate the genetic predictors of early death in APL patients. According to the number of gene mutations per patient, the 134 APL patients were divided into three groups. All patients received arsenic trioxide (ATO) alone as induction therapy. The clinical data and gene mutations were compared and analyzed. Results A total of 134 APL patients were involved in the study. The clinical data of sex, WBC, PT, and DD, UA, and LDH level were significantly different between the three groups (P = 0.000, P = 0.000, P = 0.009, P = 0.020, P = 0.030, P = 0.001 and P = 0.014, respectively). Meanwhile, among them, the Sanz risk stratification and early death rate were significantly different (P = 0.001). The early death rate was 10.4%, and the median time to early death was 6.6 days (range 2–15 days). For the next-generation sequencing, a mean of 1.28 ± 1.06 mutations per patient was detected (range: 0–5). The univariate and the multivariate regression analysis showed that age > 50[HR = 1.666, CI (1.027–2.702), P = 0.039], high WBC count [HR = 4.702, CI (1.026–21.543), P = 0.046] and low ALB levels [HR = 4.547, CI (1.088–18.995), P = 0.038] were independent risk factors for early death in APL patients (AU)

Gene mutations in acute promyelocytic leukemia early death in patients treated with arsenic trioxide alone.

PURPOSE: APL patients have recurrent alterations in FLT3, WT1, NRAS and KRAS. Gene mutations have a strong potential for involvement in pathogenesis and may have potential effects on the clinical manifestations. Gene mutations may even be associated with early death (ED) in APL patients. However, there is little published information on mutations in APL patients and whether they are attributed to early death. METHODS: In this study, we retrospectively analyzed the clinical data and gene mutations of 134 de novo APL patients. We detected the gene mutations by next-generation sequencing (NGS) to investigate the genetic predictors of early death in APL patients. According to the number of gene mutations per patient, the 134 APL patients were divided into three groups. All patients received arsenic trioxide (ATO) alone as induction therapy. The clinical data and gene mutations were compared and analyzed. RESULTS: A total of 134 APL patients were involved in the study. The clinical data of sex, WBC, PT, and DD, UA, and LDH level were significantly different between the three groups (P = 0.000, P = 0.000, P = 0.009, P = 0.020, P = 0.030, P = 0.001 and P = 0.014, respectively). Meanwhile, among them, the Sanz risk stratification and early death rate were significantly different (P = 0.001). The early death rate was 10.4%, and the median time to early death was 6.6 days (range 2-15 days). For the next-generation sequencing, a mean of 1.28 ± 1.06 mutations per patient was detected (range: 0-5). The univariate and the multivariate regression analysis showed that age > 50[HR = 1.666, CI (1.027-2.702), P = 0.039], high WBC count [HR = 4.702, CI (1.026-21.543), P = 0.046] and low ALB levels [HR = 4.547, CI (1.088-18.995), P = 0.038] were independent risk factors for early death in APL patients. Furthermore, Kaplan-Meier survival analysis, univariate analysis, and the multivariate regression analysis showed that patients with multiple gene mutations [HR = 2.258, CI (1.115-4.571), P = 0.024], KRAS [HR = 5.136, CI (1.356-19.455), P = 0.016] and/or GATA2 [HR = 4.070, CI (1.287-12.877), P = 0.017] have a significantly higher early death rate. CONCLUSION: The results of this investigation show that both molecular markers and clinical variables should be used as potential predictors for early death in APL patients. Our results suggested that age > 50, high WBC count, low ALB levels, and the presence of multiple gene mutations, KRAS and/or GATA2 at the time of diagnosis were independent risk factors for early death in APL patients. For these patients, clinicians should be more cautious during the course of induction treatment.

Characteristics and clinical influence factors of arsenic species in plasma and their role of arsenic species as predictors for clinical efficacy in acute promyelocytic leukemia (APL) patients treated with arsenic trioxide.

Background: Arsenic trioxide (ATO) is successfully applied to treat acute promyelocytic leukemia (APL). Arsenic species levels in blood are critical to reveal metabolic mechanism and relationship between arsenic species and clinical response. Characteristics and influence factors of arsenic species in APL patients have not been studied.Methods: 305 plasma samples from APL patients treated with ATO were analyzed using HPLC-HG-AFS. Trough concentration (Ctrough), distribution, methylation levels of arsenic species were evaluated. The influence factors on arsenic species levels of plasma and association between arsenic concentrations and clinical efficacy were explored.Results: Ctrough of arsenic in effective treatment groups provide basis for defining the target range of arsenic plasma concentrations in APL patients treated with ATO. Distribution trends: DMAV > AsIII, MMAV> AsV (p < 0.0001) for continuous slow-rate (CS) infusion and DMAV > MMAV > AsIII > AsV (p < 0.0001) for conventional infusion. Infusion methods and combined medication may affect arsenic metabolism. There was a weak correlation between ATO dose and plasma Ctrough of arsenic species. Ctrough of plasma arsenic species had predictive value for treatment efficacy.Conclusion: Arsenic concentration monitoring in APL patients treated with ATO is required. These findings are critical to optimize treatment outcomes of ATO therapy.

Characteristics of arsenic species in cerebrospinal fluid (CSF) of acute promyelocytic leukaemia (APL) patients treated with arsenic trioxide plus mannitol.

Arsenic speciation in cerebrospinal fluid (CSF) is critical for treatment/prevention of central nervous system (CNS) relapse in acute promyelocytic leukaemia (APL) patients treated with arsenic trioxide (ATO). Previous study showed low total arsenic level in CSF of APL patients. Mannitol infusion was applied to improve blood-brain barrier (BBB) permeability for arsenic. Arsenite (AsIII ), monomethylarsonic acid (MMAV ), dimethylarsinic acid (DMAV ), and arsenate (AsV ) in CSF and plasma were analysed by high performance liquid chromatography-hydride generation-atomic fluorescence spectrometry (HPLC-HG-AFS). The profile and concentration of arsenic species in CSF from APL patients administered ATO alone and in combination with mannitol were compared. The overall distribution trend of arsenic species in CSF was AsIII , DMAV > MMAV > AsV . Arsenicals accumulated in CSF with administration frequency. The permeability of BBB for AsIII was higher than that for MMAV and DMAV . Arsenic concentration in CSF was much lower than that in plasma. There were significantly higher arsenic species concentrations in CSF of APL patients treated with mannitol than that without mannitol. Mannitol infusion significantly increased AsIII penetration into CSF, which was beneficial to optimize efficacy in APL patients with CNS relapse.

Growth inhibition and suppression of the mTOR and Wnt/ß-catenin pathways in T-acute lymphoblastic leukemia by rapamycin and MYCN depletion.

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy. Understanding of the molecular pathogenesis may lead to novel therapeutic targets. Rapamycin, the mammalian target of rapamycin (mTOR) inhibitor, showed inhibitory effects on T-ALL cells. In this study, we showed that rapamycin significantly reduced MYCN mRNA and protein in a concentration-dependent manner in T-ALL cells. Selective knockdown of MYCN by small interfering RNA had similar effects to rapamycin to inhibit T-ALL proliferation and colony formation and to induce G1-phase cell-cycle arrest and apoptosis. The inhibitory effects of rapamycin and MYCN depletion were also found in a Molt-4 xenograft model. Rapamycin and MYCN inhibition suppressed both Wnt/ß-catenin and mTOR signaling pathways. The results suggest the effects of rapamycin on adult T-ALL is likely mediated by downregulation of MYCN. The findings suggest MYCN a potential target for the treatment of adult T-ALL. Additionally, dual targeting of mTOR and Wnt/ß-catenin pathways may represent a novel strategy in the treatment of adult T-ALL.

Development and validation of a prediction model (AHC) for early identification of refractory thrombotic thrombocytopenic purpura using nationally representative data.

Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is a rare and life-threatening haematological emergency. Although therapeutic plasma exchange together with corticosteroids achieve successful outcomes, a considerable number of patients remain refractory to this treatment and require early initiation of intensive therapy. However, a method for the early identification of refractory iTTP is not available. To develop and validate a model for predicting the probability of refractory iTTP, a cohort of 265 consecutive iTTP patients from 17 large medical centres was retrospectively identified. The derivation cohort included 94 patients from 11 medical centres. For the validation cohort, we included 40 patients from the other six medical centres using geographical validation. An easy-to-use risk score system was generated, and its performance was assessed using internal and external validation cohorts. In the multivariable logistic analysis of the derivation cohort, three candidate predictors were entered into the final prediction model: age, haemoglobin and creatinine. The prediction model had an area under the curve of 0.886 (95% CI: 0.679-0.974) in the internal validation cohort and 0.862 (95% CI: 0.625-0.999) in the external validation cohort. The calibration plots showed a high agreement between the predicted and observed outcomes. In conclusion, we developed and validated a highly accurate prediction model for the early identification of refractory iTTP. It has the potential to guide tailored therapy and is a step towards more personalized medicine.

Influence of AS3MT polymorphisms on arsenic metabolism and liver injury in APL patients treated with arsenic trioxide.

Arsenic-induced side effects limit its application in the treatment of acute promyelocytic leukemia (APL). We recently demonstrated that AS3MT 14215 (rs3740390) genotypes were associated with urinary arsenic metabolites and hematological and biochemical values. To further decipher the role of AS3MT genotypes on arsenic metabolism and toxicity, AS3MT 27215 (rs11191446), 35587 (rs11191453), 35991 (rs10748835), and their interactive effects were examined in fifty APL patients treated with arsenic trioxide (As2O3) for the first time. Urinary arsenic metabolites and methylation capacity indexes were evaluated by the percentage of inorganic arsenic (iAs), monomethylarsonate (MMA), dimethylarsinate (DMA), primary methylation index (PMI, MMA/iAs), secondary methylation index (SMI, DMA/MMA), and total methylation index (TMI, [MMA+DMA]/iAs). Results showed 27215 (rs11191446) genotypes had no statistical significance in arsenic metabolism, as only 5 (10%) patients were the non-wild-type genotypes. 35587 (rs11191453) genotypes were significantly associated with MMA%, DMA%, and SMI. 35991 (rs10748835) genotypes were significantly associated with iAs%, DMA%, PMI, TMI, and the level of ALT and AST. Patients with both 35587 (rs11191453) TT and 35991 (rs10748835) AG+GG genotypes were significantly associated with DMA% and SMI. In addition, patients with both 35991 (rs10748835) AA and 35587 (rs11191453) TC+CC genotypes had the highest DMA%, SMI, and TMI, but the lowest iAs%, ALT and AST level, indicating that additive effects exist on arsenic metabolism and liver function. Our data promotes the realization that AS3MT 35587 (rs11191453), 35991 (rs10748835), especially their joint genotypes 35991 (rs10748835) AA / 35587 (rs11191453) TC+CC, is a novel predictive biomarker for the therapeutic efficacy of As2O3 in the treatment of APL.