[Using next generation sequencing technology to analyze gene mutations in patients with acute myeloid leukemia and the impact on prognosis].

Objective: To analyze the distribution of gene mutations in newly diagnosed acute myeloid leukemia (AML) patients, based on next generation sequencing technology (NGS) and to evaluate their value in AML risk stratification. Methods: The study analyzed 453 newly diagnosed AML(excluded acute promyelocytic leukemia, APL) patients from seven hospitals in Shanghai, from January 1st 2014 to December 31th 2017. RNA and DNA were extracted from pretreatment bone marrow mononuclear cells and targeted sequencing of AML genes were performed. The data of different groups was compared. Results: A total of 453 newly diagnosed AML patients were enrolled in the study, including 247 males and 206 females with a median age of 49.5 (range,11-85) years. A total of 540 mutations/fusion genes were detected in 289 patients, 29.1% (132/259) of whom with two or more mutations/fusion genes. In all patients, NPM1 was the most common mutation(12.8%), followed by ETO and TET2 mutation (11.92% and 11.04%, respectively) . And WT1 over-expression accounted for 10.6%. Patients over the age of 50 were with a higher frequency of mutations associated with epigenetic modification, 11.93% for ASXL1, 13.99% for DMNT3A, 6.58% for IDH1/IDH2, and 13.17% for TET2. The frequency of DMNT3A mutations was three times higher than that of patients under 50 years of age (P=0.017). In this study, a relatively low proportion of genetic mutations was observed in low-risk karyotype group. In the medium-risk karyotype group, the relatively high mutation frequencies were observed in NPM1, TET2, FLT3-ITD, DNMT3A, ASXL1, and CEBPA genes. In the poor-risk karyotype group, the mutation frequencies of ASXL1, TET2, DNMT3A and PHF6 genes were more than 10%, especially ASXL1 and PHF6 mutation frequencies were significantly higher than other molecular risk stratification groups (P<0.05). Of the 254 patients (56%) with normal karyotype AML (NK-AML), 56 patients were detected to have gene mutations about epigenetic modification. The median OS of this group was worse than that of patients without related mutations, while the median LFS had no significant difference. In patients with NK-AML older than 50 years, the OS and LFS of patients with epigenetic modification related gene mutations was 12 months and 10 months, versus 18 months and 12 months of patients without mutations. Conclusions: The gene mutations frequencies in AML patients with different age and molecular risk stratification groups are different. Epigenetics gene mutation frequencies, such as DNMT3A, ASXL1, IDH1/IDH2 and TET2,are higher in patients older than 50 years. A shorter OS can be observed in older patients(>50 years) with epigenetics gene mutation.

[Effect of early tocilizumab intervention on patients with cytokine release syndrome following chimeric antigen receptor T cell therapy].

Objective: This study aimed to evaluate the effect of early tocilizumab intervention to relieve cytokine release syndrome (CRS) following chimeric antigen receptor T cell (CAR-T) therapy. Methods: Twenty-two patients with acute lymphoblastic leukemia who received tocilizumab to relieve CRS response after CAR-T cell infusion in our research center from October 2015 to July 2021 were retrospectively analyzed. According to the timing of tocilizumab intervention, patients were divided into the conventional and early intervention groups. Patients who received tocilizumab treatment after sustained high fever for 4 h were included in the early intervention group. The clinical data, CRS grade, and event-free survival (EFS) between the two groups were evaluated. Results: Compared with patients who used tocilizumab after severe CRS, no patients in the early intervention group died from CRS, and there was no increased risk of neurotoxicity. Eleven patients (84.62%) achieved complete remission with minimal residual lesions. The median EFS of patients in the early intervention and conventional groups was 2 (95% CI 0-5) and 7 (95% CI 3-11) months, respectively. Conclusion: Early tocilizumab intervention in patients with CRS reduces severe CRS and provides a more optimized therapeutic strategy for CRS caused by CAR-T cell therapy.

[Efficacy and safety analysis of the zanubrutinib-based bridging regimen in chimeric antigen receptor T-cell therapy for relapsed/refractory diffuse large B-cell lymphoma].

Objective: To further elucidate the clinical efficacy and safety of a combination regimen based on the BTK inhibitor zebutanil bridging CD19 Chimeric antigen receptor T cells (CAR-T cells) in the treatment of relapsed/refractory diffuse large B-cell lymphoma (r/r DLBCL) . Methods: Twenty-one patients with high-risk r/r DLBCL were treated with a zanubrutinib-based regimen bridging CAR-T between June 2020 and June 2023 at the Department of Hematology, Tongji Hospital, Tongji University and the Second Affiliated Hospital of Zhejiang University, and the efficacy and safety were retrospectively analyzed. Results: All 21 patients were enrolled, and the median age was 57 years (range: 38-76). Fourteen patients (66.7%) had an eastern cooperative oncology group performance status score (ECOG score) of ≥2. Eighteen patients (85.7%) had an international prognostic index (IPI) score of ≥3. Three patients (14.3%) had an IPI score of 2 but had extranodal infiltration. Fourteen patients (66.7%) had double-expression of DLBCL and seven (33.3%) had TP53 mutations. With a median follow-up of 24.8 (95% CI 17.0-31.6) months, the objective response rate was 81.0%, and 11 patients (52.4%) achieved complete remission. The median progression-free survival (PFS) was 12.8 months, and the median overall survival (OS) was not reached. The 1-year PFS rate was 52.4% (95% CI 29.8% -74.3%), and the 1-year OS rate was 80.1% (95% CI 58.1% -94.6%). Moreover, 18 patients (85.7%) had grade 1-2 cytokine-release syndrome, and two patients (9.5%) had grade 1 immune effector cell-associated neurotoxicity syndrome. Conclusion: Zanubrutinib-based combination bridging regimen of CAR-T therapy for r/r DLBCL has high efficacy and demonstrated a good safety profile.

Expression of CD147 in advanced non-small cell lung cancer correlated with cisplatin-based chemotherapy resistance.

CD147, a widely expressed cell surface glycoprotein in cancer, is associated with tumor invasiveness and chemotherapy resistance. Recently, CD147 is also regarded as a potential therapeutic target for cancer therapy. The aim of the study was to investigate CD147 expression in non-small cell lung cancer (NSCLC), and evaluate its correlation with cisplatin-based chemotherapy resistance. In this study, we examined immunohistochemically the expression of CD147 in 118 advanced NSCLC cases treated with cisplatin-based chemotherapy, and then the association of CD147 expression with clinicopathological characteristics was analyzed. Furthermore, RNA interference approach was used to silence CD147 expression in a cisplatin-resistant human lung cancer cell line A549/DDP, and the inhibition effect of cisplatin on tumor cells was assayed by MTT. In the overall series, positive CD147 expression was observed in 101/118 (85.6%) cases. A membranous CD147 pattern was identified in 76/101 (75.2%) of CD147 positive tumors. CD147 membranous expression,but not the overall CD147 expression, was associated with poor response to cisplatin-based chemotherapies and a poor prognosis in advanced NSCLC patients. In vitro results showed that silencing CD147 increased the proliferation inhibitory effect of cisplatin to A549/DDP cells. In conclusion, our study indicated that membranous CD147 expression is a predictive factor of the response to cisplatin-based chemotherapies, and the use of CD147-targeted therapeutic adjuvants might be considered in the treatment of advanced NSCLC patients.

Targeting HDAC3, a new partner protein of AKT in the reversal of chemoresistance in acute myeloid leukemia via DNA damage response.

Resistance to cytotoxic chemotherapy drugs remains as the major cause of treatment failure in acute myeloid leukemia. Histone deacetylases (HDAC) are important regulators to maintain chromatin structure and control DNA damage; nevertheless, how each HDAC regulates genome stability remains unclear, especially under genome stress conditions. Here, we identified a mechanism by which HDAC3 regulates DNA damage repair and mediates resistance to chemotherapy drugs. In addition to inducing DNA damage, chemotherapy drugs trigger upregulation of HDAC3 expression in leukemia cells. Using genetic and pharmacological approaches, we show that HDAC3 contributes to chemotherapy resistance by regulating the activation of AKT, a well-documented factor in drug resistance development. HDAC3 binds to AKT and deacetylates it at the site Lys20, thereby promoting the phosphorylation of AKT. Chemotherapy drug exposure enhances the interaction between HDAC3 and AKT, resulting in decrease in AKT acetylation and increase in AKT phosphorylation. Whereas HDAC3 depletion or inhibition abrogates these responses and meanwhile sensitizes leukemia cells to chemotoxicity-induced apoptosis. Importantly, in vivo HDAC3 suppression reduces leukemia progression and sensitizes MLL-AF9+ leukemia to chemotherapy. Our findings suggest that combination therapy with HDAC3 inhibitor and genotoxic agents may constitute a successful strategy for overcoming chemotherapy resistance.

A stress-induced cellular aging model with postnatal neural stem cells.

This corrects the article DOI: 10.1038/cddis.2014.82.

[A multicenter, retrospective study of pathogenic bacteria distribution and drug resistance in febrile neutropenic patients with hematological diseases in Shanghai].

Objective: To investigate the pathogen spectrum distribution and drug resistance of febrile neutropenic patients with hematological diseases in Shanghai. Methods: A retrospective study was conducted on the clinical isolates from the febrile neutropenic patients hospitalized in the departments of hematology in 12 general hospitals in Shanghai from January 2012 to December 2014. The drug susceptibility test was carried out by Kirby-Bauer method. WHONET 5.6 software was used to analyze pathogenic bacteria and drug susceptibility data. Results: A total of 1 260 clinical isolates were collected from the febrile neutropenic patients. Gram-positive bacteria accounted for 33.3% and Gram-negative bacteria accounted for 66.7%. Klebsiella pneumoniae (12.5%) , Stenotrophomonas maltophilia (9.5%) , Escherichia coli (9.1%) , Pseudomonas aeruginosa (8.7%) , Acinetobacter baumannii (6.6%) , Staphylococcus aureus (5.6%) and Enterococcus faecium (5.0%) were ranked in the first 7 of all pathogens. In the respiratory tract secretions specimens, non-fermented strains accounted for 56.2%. Stenotrophomonas maltophilia accounted for 15.2%. Enterobacteriaceae and coagulase-negative Staphylococci accounted for 42.3% (104/246) and 32.6% (85/246) respectively in blood samples. Enterobacteriaceae and Enterococcus bacteria accounted for 39.4% (76/193) and 28.5% (55/193) respectively in pus specimens. The detection rates of methicillin resistant Staphylococcus aureus (MRSA) and methicillin resistant coagulase negative Staphylococci (MRCNS) were 54.3% and 82.5%, respectively. Staphylococcus bacterial strain was not found to be resistant to linezolid, vancomycin and teicoplanin. The detection rate of Enterococcus vancomycin-resistant strains was 8.9%. Enterococcus was not detected resistance to oxazolidinone strains. Enterobacteriaceae bacteria were highly sensitive to carbapenems. The resistance rate of Pseudomonas aeruginosa to imipenem and meropenem was 34.1% and 15.8%, respectively. Stenotrophomonas maltophilia was more sensitive to minocycline hydrochloride, levofloxacin and sulfamethoxazole. The resistance rate of Acinetobacter baumannii only to cefoperazone-sulbactam was less than 10.0%. The antibiotic resistance rate of Klebsiella pneumoniae, Stenotrophomonas maltophilia, Pseudomonas aeruginosa and Acinetobacter baumanii to most of common antibiotics was lower than that of the CHINET surveillance. Conclusions: The pathogenic strain distribution in common infection sites of febrile neutropenic patients was characterized. Bacterial resistance surveillance was better than the CHINET nationwide large sample surveillance in China.

IL-10 induces the development of immunosuppressive CD14(+)HLA-DR(low/-) monocytes in B-cell non-Hodgkin lymphoma.

The biological role of monocytes and macrophages in B-cell non-Hodgkin lymphoma (NHL) is not fully understood. We have previously reported that monocytes from patients with B-cell NHL have an immunosuppressive CD14(+)HLA-DR(low/-) phenotype that correlates with a poor prognosis. However, the underlying mechanism by which CD14(+)HLA-DR(low/-) monocytes develop in lymphoma is unknown. In the present study, we found that interleukin (IL)-10, which is increased in the serum of patients with B-cell NHL, induced the development of the CD4(+)HLA-DR(low/-) population. Using peripheral blood samples from patients with B-cell NHL, we found that absolute numbers of CD14(+) monocytic cells with an HLA-DR(low/-) phenotype were higher than healthy controls and correlated with a higher International Prognostic Index score. IL-10 serum levels were elevated in lymphoma patients compared with controls and were associated with increased peripheral monocyte counts. Treatment of monocytes with IL-10 in vitro significantly decreased HLA-DR expression and resulted in the expansion of CD14(+)HLA-DR(low/-) population. We found that lymphoma B cells produce IL-10 and supernatants from cultured lymphoma cells increased the CD14(+)HLA-DR(low/-) population. Furthermore, we found that IL-10-induced CD14(+)HLA-DR(low/-) monocytes inhibited the activation and proliferation of T cells. Taken together, these results suggest that elevated IL-10 serum levels contribute to increased numbers of immunosuppressive CD14(+)HLA-DR(low/-) monocytes in B-cell NHL.

A stress-induced cellular aging model with postnatal neural stem cells.

Aging refers to the physical and functional decline of the tissues over time that often leads to age-related degenerative diseases. Accumulating evidence implicates that the senescence of neural stem cells (NSCs) is of paramount importance to the aging of central neural system (CNS). However, exploration of the underlying molecular mechanisms has been hindered by the lack of proper aging models to allow the mechanistic examination within a reasonable time window. In the present study, we have utilized a hydroxyurea (HU) treatment protocol and effectively induced postnatal subventricle NSCs to undergo cellular senescence as determined by augmented senescence-associated-ß-galactosidase (SA-ß-gal) staining, decreased proliferation and differentiation capacity, increased G0/G1 cell cycle arrest, elevated reactive oxygen species (ROS) level and diminished apoptosis. These phenotypic changes were accompanied by a significant increase in p16, p21 and p53 expression, as well as a decreased expression of key proteins in various DNA repair pathways such as xrcc2, xrcc3 and ku70. Further proteomic analysis suggests that multiple pathways are involved in the HU-induced NSC senescence, including genes related to DNA damage and repair, mitochondrial dysfunction and the increase of ROS level. Intriguingly, compensatory mechanisms may have also been initiated to interfere with apoptotic signaling pathways and to minimize the cell death by downregulating Bcl2-associated X protein (BAX) expression. Taken together, we have successfully established a cellular model that will be of broad utilities to the molecular exploration of NSC senescence and aging.