[Clinical Characteristics and Prognostic Relevance of Co-Mutated Genes in Acute Myeloid Leukemia Patients with FLT3 Mutations].

OBJECTIVE: To investigate the clinical characteristics and influence of co-mutated gene on acute myeloid leukemia patients (AML) with FMS-like tyrosine kinase-3 (FLT3) mutations. METHODS: A total of 273 FLT3+ AML patients were enrolled, and the co-mutation gene data of the patients were collected to further analyze the prognosis of the patients. FLT3 and other common mutations were quantified by PCR amplification products direct sequencing and second-generation sequencing (NGS). RESULTS: When patients were divided into FLT3- ITD +, FLT3- TKD +, FLT3- ITD ++TKD + and FLT3- ITD -+TKD - group according to the type of FLT3 mutations, it was found that the frequencies of TET2, GATA2, NRAS and ASXL1 mutation were significantly different among the 4 groups (all P < 0.05). When patients were divided into allelic ratio (AR) ≥0.5 and <0.5 group, it was found that the frequencies of FLT3- ITD +, FLT3 -ITD - +TKD -, NPM1, NRAS and C-kit were significantly different between the two groups (all P < 0.05). When patients were divided into normal and abnormal karyotype group, it was found that the frequencies of FLT3- ITD +, FLT3- TKD +, NPM1, GATA2 and C-kit were significantly different between the two groups (all P < 0.05). The median overall survival (OS) of AML patients with FLT3 -TKD + (including FLT3- ITD ++TKD +) was longer than that of patients with FLT3- ITD + alone (P < 0.05). The OS and relapse-free survival (RFS) of AML patients with FLT3++TET2+ were both shorter than those of patients with FLT3++TET2- (both P < 0.05). CONCLUSION: The mutation frequencies of co-mutated genes are correlated with subtypes of FLT3, karyotype and AR. AML patients with FLT3 -TKD + have longer OS than patients with FLT3- ITD + alone, and patients with co-mutation of TET2 have shorter median OS and RFS.

A CD36-dependent non-canonical lipid metabolism program promotes immune escape and resistance to hypomethylating agent therapy in AML.

Environmental lipids are essential for fueling tumor energetics, but whether these exogenous lipids transported into cancer cells facilitate immune escape remains unclear. Here, we find that CD36, a transporter for exogenous lipids, promotes acute myeloid leukemia (AML) immune evasion. We show that, separately from its established role in lipid oxidation, CD36 on AML cells senses oxidized low-density lipoprotein (OxLDL) to prime the TLR4-LYN-MYD88-nuclear factor κB (NF-κB) pathway, and exogenous palmitate transfer via CD36 further potentiates this innate immune pathway by supporting ZDHHC6-mediated MYD88 palmitoylation. Subsequently, NF-κB drives the expression of immunosuppressive genes that inhibit anti-tumor T cell responses. Notably, high-fat-diet or hypomethylating agent decitabine treatment boosts the immunosuppressive potential of AML cells by hijacking CD36-dependent innate immune signaling, leading to a dampened therapeutic effect. This work is of translational interest because lipid restriction by US Food and Drug Administration (FDA)-approved lipid-lowering statin drugs improves the efficacy of decitabine therapy by weakening leukemic CD36-mediated immunosuppression.

[The Risk and Survival Analysis of Multiple Malignancies in Hematologic Malignancy Patients: A Single Chinese Center Retrospective Study, 2009 through 2017].

OBJECTIVE: To explore the risk and location of multiple malignancies in patients with hematologic malignancies who were followed up for 9 years in Jiangsu Province Hospital and to evaluate the impact of the second primary malignancy on survival of patients. METHODS: The incidence and survival of multiple malignancies in 7 921 patients with hematologic malignancies from 2009 to 2017 were analyzed retrospectively. RESULTS: A total of 180 (2.3%, 180/7 921) patients developed second malignancy, of whom 58 patients were diagnosed with hematologic malignancies as the first primary malignancy, and 98 patients developed hematologic malignancies as second primary malignancy, and the other 24 cases were diagnosed with the second malignancy within 6 months after the first primary malignancy was diagnosed, which was difined as multiple malignancies occurring simultaneously. In 180 patients, 18 cases developed two hematologic malignancies successively, and 11 patients developed more than 3 primary cancers (among them, 2 female patients were diagnosed with 4 primary cancers). Patients with lymphoma and multiple myeloma (MM) as the second primary malignancy had poorer survival than patients with lymphoma and MM as the first primary malignancy. Patients with chronic myeloid leukemia as the second primary malignancy were also associated with inferior overall survival. CONCLUSION: In this study, 2.3% of hematologic malignancy patients had multiple mali-gnancies, lymphoma and MM as the second primary malignancy had poor survival.

[Efficacy and Safety of Decitabine Combined with Modified CAG Regimen in Patients Aged ≥ 70 Years with Newly Diagnosed Acute Myeloid Leukemia].

OBJECTIVE: To evaluate the clinical efficacy and safety of decitabine combined with modified CAG regimen (D-CAG regimen) in patients aged ≥70 years with newly diagnosed acute myeloid leukemia (AML). METHODS: The clinical data of 59 AML patients (≥70 years old) who were newly diagnosed and treated in the Hematology Department of the First Affiliated Hospital of Nanjing Medical University from November 2010 to June 2021 were retrospectively analyzed. RESULTS: Among the 59 AML patients, 28 were males and 31 were females, with a median age of 74 (70-86) years. The complete remission (CR) rate was 69.4% (34/49), and the median duration of CR was 10.7 (0.6-125.4) months after 2 courses of D-CAG treatment. According to the British Medical Research Council (MRC) classification, there was only one patient in the favorable-risk group, and the CR rate was 71.8% (28/39) in the intermediate-risk group, and 55.6% (5/9) in the adverse-risk group, respectively. There was no statistical difference in the CR rate between the intermediate-risk and adverse-risk group. Referring to ELN 2017 genetic risk classification, CR rate was 88.2% (15/17) in the favorable-risk group, 45.5% (5/11) in the intermediate-risk group, and 66.7% (14/21) in the adverse-risk group. There was no significant difference in CR rate between the favorable-risk and adverse-risk categories, but both were significantly higher than that in the intermediate-risk group (P <0.05). Next-generation sequencing (NGS) analysis showed that 11 gene mutations with a frequency of more than 10%, including TET2 mutation (35.6%), ASXL1 mutation (30.5%), NPM1 mutation (28.8%), FLT3-ITD mutation (27.1%), DNMT3A mutation (22.0%), IDH1 mutation (15.3%), CEBPA single mutation (13.6%), TP53 mutation (13.6%), IDH2 mutation (11.9%), RUNX1 mutation (11.9%), and NRAS mutation (10.2%). There were no statistical differences in mutation frequency of these 11 genes between CR group and non-CR group. Compared with normal karyotypes, patients with complex karyotypes were more likely to develop TP53 mutations (P <0.001), while FLT3-ITD and DNMT3A mutations were more likely to occur in patients with normal karyotypes (P =0.04, P =0.047). The median follow-up, overall survival (OS), and event-free survival (EFS) of all the patients was 11.7 (1.5-128.2) months, 12.3 (1.5-128.2) months, and 8.5 (1.5-128.2) months, respectively. The median OS and EFS of CR patients were 19.8 and 13.3 months, respectively, which were significantly longer than 6.4 and 5.7 months in patients experiencing treatment failure (P < 0.001, P =0.009). In regard to genes with mutation frequency >10%, there were no statistical differences in CR rate, median OS, and median EFS between mutated and wild-type patients by Chi-square test and survival analysis. Univariate analysis showed that age, hemoglobin, lactate dehydrogenase, cytogenetics and CR were factors affecting prognosis, while multivariate analysis showed that only CR failure was an independent adverse prognostic factor for OS. The major adverse reactions to D-CAG regimen were grade 3-4 myelosuppression, pulmonary infection, and fever (infection focus was not identified). CONCLUSION: D-CAG regimen is safe and effective in the treatment of AML patients ≥70 years old, and can partially improve the prognosis of elderly and high-risk patients.

[Clinical efficacies and safety of HAG regimen for patients with high-risk myelodysplastic syndromes: a multicentre study].

OBJECTIVE: To evaluate the efficacies and toxicity of HAG (HHT + Ara-C + G-CSF) regimen in patients with high-risk myelodysplastic syndromes (MDS). METHODS: A total of 97 patients with high-risk MDS received HAG regimen as the induction therapy. RESULTS: The complete remission (CR) rate of all the patients was 52.3% (45/86). The overall response (OR) rate was 66.3% (57/86). The early mortality rate was 9.3% (9/97). There was no significant difference in CR rate and OR rate between the patients aged ≥ 60 and those < 60. The OR rate was 29/34, 9/12 and 6/13 in patients with favorable karyotype, intermediate karyotype and unfavorable karyotype respectively. The OR rate was higher in patients with favorable karyotype than those with unfavorable karyotype (P = 0.038). The major adverse effect was infection. CONCLUSION: HAG regimen provides higher CR rate and OR rate for patients with high-risk MDS.

[The Expression and Function of NK Cells in Patients with Acute Myeloid Leukemia].

OBJECTIVE: To explore the expression characteristics of antigens and functional markers of natural killer (NK) cells in patients with acute myeloid leukemia (AML). METHODS: Multi-parameter flow cytometry was used to detect NK cell surface markers and their functional indicators in 56 newly diagnosed AML patients and 24 healthy controls, including activating receptors NKG2D, NKP46, DNAM-1, and killing indicators granzyme B, perforin. RESULTS: Referring to the WHO hematopoiesis and lymph tissue tumor classification criteria, 56 cases were roughly divided into three types: AML M1, M2, and M4/M5. However, there was no differences about NK cells among the three types, so it was no longer subdivided. NK cells were divided into two groups: CD3-CD56hiCD16- (CD56hiNK) and CD3-CD56dimCD16+ (CD56dimNK). Compared with CD56dimNK cell population, except for NKP46, the positive expression levels of NKG2D and other receptors of CD56hiNK cells in AML patients decreased (P<0.001). Compared with healthy controls, the proportion of CD56hiNK cells in AML patients increased, while the number and proportion of NK cells and proportion of CD56dimNK cells significantly decreased (P<0.05). The proportion of perforin in CD56hiNK cells significantly increased (P<0.05). The expression of DNAM-1 in CD56hiNK cells, NKG2D, DNAM-1, and perforin in CD56dimNK cells decreased significantly (P<0.05). There was no statistically significant difference in expression of other functional indexes in AML patients compared with corresponding indexes of healthy controls. In addition, the proportion of CD56hiNK cells was positively correlated with the expression of CD34+ in AML (r=0.303). CONCLUSION: Compared with CD56dimNK, the ratio of CD56hiNK and the expression of functional markers in AML patients are lower. Compared with healthy controls, the number and expression ratio of NK cells in AML patients decrease and the expression of functional markers is abnormal, indicating that its function is impaired.

[Analysis of the Differential Expression of circRNA in Acute Myeloid Leukemia by GEO Database].

OBJECTIVE: To investigate the difference expression of circular RNA (circRNA) in acute myeloid leukemia (AML) by using bioinformatics method. METHODS: The microarray chip data of AML was searched and downloaded from the Gene Expression Omnibus (GEO) of the National Center for Bioinformatics (NCBI). The differences between AML samples and control samples were analyzed by R software. The interaction between deregulated circRNA, miRNA and mRNA were predicted by miranda software and miRTarBase software. The circRNA-miRNA-mRNA regulatory network was constructed by using the cytoHubba plugin based on the Cytoscape software. RESULTS: A total of 203 differential expression of circRNAs were finally collected, including down-regulated 161 circRNAs and up-regulated 42 circRNAs. CircRNA/miRNA/mRNA interaction network was constructed through software prediction. hsa_circ_0001080, hsa_circ_0004511, hsa_circ_0054211, hsa_circ_0001944 may be positively regulated the gene expression in AML. CONCLUSION: Abnormal expression of circRNA in AML may become a new target for AML treatment.

[A Retrospective Analysis of TKI Discontinuation in Patients with CML].

OBJECTIVE: To investigate the clinical characteristics of the patients with chronic myeloid leukemia (CML) discontinued tyrosine kinase inhibitors (TKI) therapy and the outcome of the patients. METHODS: 35 cases of CML patients experienced initiative discontinuation of TKI therapy in our hospital from June 1st 2015 to December 31th 2019 were retrospectively analyzed. The TFR of the patients and the factors affecting it were analyzed. RESULTS: The median duration of TKI administration was 72 (range 35-173) months in the 35 patients. Among these patients, 8 had experienced TKI dose reduction or suspension. All the enrolled patients have achieved at least MMR. The median time for these patients achieving MMR was 15 (range 3-75) months after administration of TKI, and for MMR maintenance before TKI suspension was 55 (range 13-164) months. After TKI withdrawal the median follow up time was 20.3 (range 3-57.9) months, 22 out of 35 patients kept TFR, among them, 2 （5.71%） patients restarted TKI after 12 month suspension, and maintained MMR during suspension. 13 （37.1%）patients lost MMR, among them, 9 patients restarted TKI treatment, and 5 of them achieved MR4.0 after the median duration of 3(2-5) month. No patients were found to have disease progression. The estimated TFR rate was 57.8% and 51.8% at 12 and 24 months after discontinuation, respectively. Other clinical characteristic related to relapse were also analyzed, including the cumulative TKI administration duration, cumulative MMR duration, time to achieve MMR, median age at diagnosis, risk stratification by Sokal score, TKI dose reduction and discontinuation history, and second-generation TKI administration before stopping TKI, however, no statistical difference was found. CONCLUSION: TKI discontinuation is practical for CML patients in our center.

[Distribution of Natural Killer Cell in Patients with Newly Diagnosed Myelodysplastic Syndromes and Its Correlation with Prognosis].

OBJECTIVE: To investigate the distribution of peripheral blood lymphocytes and natural killer (NK) cells, and its influence on the prognosis of patients with myelodysplastic syndromes (MDS). METHODS: The lymphocytes proportion, absolute lymphocyte counts (ALC), NK cell proportion and absolute NK cell counts (ANKC) as well as the related data of 95 MDS patients diagnosed between 2013 and 2017 analyzed retrospectively. The correlation of ALC and ANKC with prognosis was also analyzed. RESULTS: As compared with low ALC patients, MDS patients with ALC≥0.885×109/L had a higher overall response rate (66.7% vs 35.8%) (P＜0.01). The ALC of effective patients after treatment significatitly increased in compaison of ALC at diagnosis. Multivariate analysis indicated that patients with ALC≥0.885×109/L had long overall survival (OS) time in comparison with patients with low level (16.4 vs 12.4 months) (P＜0.05). The OS time of patients with ANKC≥0.110×109/L was shorter in comparison with patients with low level (10.9 vs 16.3 months) (P＜0.01). Otherwise, blast, cytogenetic risks and treatment response were also independent risk factors of MDS (P＜0.05). Revised International Prognostic Scoring System (IPSS-R) combined with ANKC could improve predictive accuracy of IPSS-R alone (AUC 0.718 vs 0.674) (P＜0.05). CONCLUSION: Lymphocytes and NK cells are important for the prognosis evaluation of MDS patients.

Decitabine in combination with low-dose cytarabine, aclarubicin and G-CSF tends to improve prognosis in elderly patients with high-risk AML.

We evaluated the risk status and survival outcomes of 125 elderly acute myeloid leukemia (AML) patients treated with decitabine in combination with low-dose cytarabine, aclarubicin, and G-CSF (D-CAG). The risk status was evaluated by determining the frequency of recurring gene mutations using next-generation sequencing (NGS) analysis of 23 selected genes and cytogenetic profiling of bone marrow samples at diagnosis. After a median follow-up of 12 months (range: 2-82 months), 86 patients (68.8%) had achieved complete remission after one cycle of induction, and 94 patients (75.2%) had achieved it after two cycles. The median overall survival (OS) and disease-free survival (DFS) were 16 and 12 months, respectively. In 21 AML patients aged above 75 years, the median OS and DFS were longer in the low- and intermediate-risk group than the high-risk group, but the differences were not statistically significant. The median OS and DFS were similar in patients with or without TET2, DNMT3A, IDH2, TP53 and FLT3 mutations. Multivariate analysis showed that patient age above 75 years, high-risk status, and genetic anomalies, like deletions in chromosomes 5 and/or 7, were significant variables in predicting OS. D-CAG regimen tends to improve the prognosis of a subgroup of elderly patients with high-risk AML.