The Dark Side of Pyroptosis of Diffuse Large B-Cell Lymphoma in B-Cell Non-Hodgkin Lymphoma: Mediating the Specific Inflammatory Microenvironment.

Background: Diffuse large B-cell lymphoma (DLBCL) is a common aggressive B-cell non-Hodgkin lymphoma (B-NHL). While combined chemotherapy has improved the outcomes of DLBCL, it remains a highly detrimental disease. Pyroptosis, an inflammatory programmed cell death, is considered to have both tumor-promoting and tumor-suppressing effects. The role of pyroptosis in DLBCL has been gradually appreciated, but its value needs further investigation. Methods: We analyzed mutations and copy number variation (CNV) alterations of pyroptosis-related genes (PRGs) from The Cancer Genome Atlas (TCGA) cohort and evaluated the differences in expression in normal B cells and DLBCL patients in two Gene Expression Omnibus (GEO) datasets (GSE12195 and GSE56315). Based on the expression of 52 PRGs, we divided 421 DLBCL patients from the GSE31312 dataset into distinct clusters using consensus clustering. The Kaplan-Meier method was used to prognosis among the three clusters, and GSVA was used to explore differences in the biological functions. ESTIMATE and single-sample gene-set enrichment analysis (ssGSEA) were used to analyze the tumor immune microenvironment (TME) in different clusters. A risk score signature was developed using a univariate survival analysis and multivariate regression analysis, and the reliability and validity of the signature were verified. By combining the signature with clinical factors, a nomogram was established to predict the prognosis of DLBCL patients. The alluvial diagram and correlation matrix were used to explore the relationship between pyroptosis risk score, clinical features and TME. Results: A large proportion of PRGs are dysregulated in DLBCL and associated with the prognosis. We found three distinct pyroptosis-related clusters (cluster A, B, and C) that differed significantly with regard to the prognosis, biological process, clinical characteristics, chemotherapeutic drug sensitivity, and TME. Furthermore, we developed a risk score signature that effectively differentiates high and low-risk patients. The nomogram combining this signature with several clinical indicators showed an excellent ability to predict the prognosis of DCBCL patients. Conclusions: This work demonstrates that pyroptosis plays an important role in the diversity and complexity of the TME in DLBCL. The risk signature of pyroptosis is a promising predictive tool. A correct and comprehensive assessment of the mode of action of pyroptosis in individuals will help guide more effective treatment.

Identification and Validation of a Novel RNA-Binding Protein-Related Gene-Based Prognostic Model for Multiple Myeloma.

BACKGROUND: Multiple myeloma (MM) is a malignant hematopoietic disease that is usually incurable. RNA-binding proteins (RBPs) are involved in the development of many tumors, but their prognostic significance has not been systematically described in MM. Here, we developed a prognostic signature based on eight RBP-related genes to distinguish MM cohorts with different prognoses. METHOD: After screening the differentially expressed RBPs, univariate Cox regression was performed to evaluate the prognostic relevance of each gene using The Cancer Genome Atlas (TCGA)-Multiple Myeloma Research Foundation (MMRF) dataset. Lasso and stepwise Cox regressions were used to establish a risk prediction model through the training set, and they were validated in three Gene Expression Omnibus (GEO) datasets. We developed a signature based on eight RBP-related genes, which could classify MM patients into high- and low-score groups. The predictive ability was evaluated using bioinformatics methods. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, and gene set enrichment analyses were performed to identify potentially significant biological processes (BPs) in MM. RESULT: The prognostic signature performed well in the TCGA-MMRF dataset. The signature includes eight hub genes: HNRNPC, RPLP2, SNRPB, EXOSC8, RARS2, MRPS31, ZC3H6, and DROSHA. Kaplan-Meier survival curves showed that the prognosis of the risk status showed significant differences. A nomogram was constructed with age; B2M, LDH, and ALB levels; and risk status as prognostic parameters. Receiver operating characteristic (ROC) curve, C-index, calibration analysis, and decision curve analysis (DCA) showed that the risk module and nomogram performed well in 1, 3, 5, and 7-year overall survival (OS). Functional analysis suggested that the spliceosome pathway may be a major pathway by which RBPs are involved in myeloma development. Moreover, our signature can improve on the R-International Staging System (ISS)/ISS scoring system (especially for stage II), which may have guiding significance for the future. CONCLUSION: We constructed and verified the 8-RBP signature, which can effectively predict the prognosis of myeloma patients, and suggested that RBPs are promising biomarkers for MM.

HLX affects cell cycle and proliferation in AML cells via the JAK/STAT signaling pathway.

Acute myelogenous leukemia (AML) is a class of malignant tumors derived from hematopoietic stem or progenitor cells. The H2.0-like homeobox gene (HLX) encodes transcription factors that function in promoting normal hematopoietic cell proliferation and tumor immunity. The present study analyzed the effect of downregulating the HLX on cell cycle distribution and cell proliferation in AML. Moreover, the current study detected changes in the expression of genes and proteins in the Janus kinase (JAK)/STAT signaling pathway to investigate the mechanism of the action of HLX in tumor immunity in AML. HLX expression in AML cell lines was silenced using small interfering siRNA, and MTS/PMS-assay colorimetric assays were used to assess the effect of knockdown of HLX on AML cell proliferation. Flow cytometry was used to analyze changes in cell cycle distribution, while reverse transcription-quantitative PCR and western blotting were used to detect changes in the expression levels of key components of the JAK/STAT signaling pathway, such as p21-activated kinase 1 (PAK1), neuropilin 1 (NRP1), B-cell translocation gene 1 (BTG1) and STAT5. It was found that HLX was differentially expressed in AML cell lines of various subtypes, and HLX expression was higher in the AML/M3 subtype NB4 cell line compared with the control group. Knockdown of HLX in NB4 cells significantly inhibited cell proliferation and arrested cells in the G0/G1 phase. Moreover, STAT5 protein expression, as well as NRP1 and PAK1 expression levels were downregulated, while BTG1 expression was upregulated when HLX was knocked out by siRNA. Collectively, the results suggested that downregulation of HLX may cause G0/G1 phase arrest and inhibit the proliferation of AML cells by activating the JAK/STAT signaling pathway.

SP1-mediated overexpression of lncRNA LINC01234 as a ceRNA facilitates non-small-cell lung cancer progression via regulating OTUB1.

Long noncoding RNAs (lncRNAs) have been confirmed to be strongly associated with the progression of various types of cancer. LncRNA LINC01234 (LINC01234) is a newly identified tumor-related lncRNA whose upregulation has been confirmed in some tumors. However, its potential expressions and possible functions in non-small-cell lung cancer (NSCLC) have not been explored. In this study, we first found that LINC01234 expressions were distinctly upregulated in both NSCLC samples and cell lines using RT-PCR. Our group also showed that LINC01234 upregulations were modulated by nuclear transcription factor SP1. The results form clinical investigations indicated that high LINC01234 expressions were associated with positively lymph node metastasis and advanced tumor-metastasis-node (TMN) stage. Kaplan-Meier assays indicated that patients with NSCLC having high LINC01234 expressions tend to have unfavorable clinical prognosis. Using multivariate assays, it was confirmed that LINC01234 was an independent prognostic factor for patients with NSCLC. In vitro assays showed that inhibition of LINC01234 suppressed NSCLC cell proliferation, cell colony formation and metastasis, and greatly promoted apoptosis. Mechanistic investigations revealed LINC01234 promotes the progression of NSCLC cells by the modulation of miR-140 to positively regulate OTUB1 expression. Taken together our findings, they provided an exhaustive assay of LINC01234 in NSCLC and imperative clues for insights into the potential effects of lncRNAs-miRNAs regulatory network in NSCLC.

[The induced differentiation and apoptosis of THP-1 cells by anti-CD44 antibody and its mechanism].

OBJECTIVE: To investigate the effects of anti-CD44 mAb A3D8 on the cell proliferation of human acute monocytic leukemia cell line THP-1 and its mechanism. METHODS: Cell proliferation was assayed with MTT method, the expression of CD33, CD15, CD11b, CD14, Annexin-V, caspase-3 and cell cycle with flow cytometry, and the expression of p-Akt, p-ERK, bcl-2 and p27kip1 with Western blot. RESULTS: A3D8 could remarkably inhibit the proliferation capacity of the THP-1 cells in a dosage- and time-dependent manner. THP-1 differentiation was observed when treated with A3D8 (2.0 µg/ml) for one to six days. Expression of CD33 (68.9 ± 2.0 vs 39.3 ± 1.5), CD15 (61.7 ± 5.5 vs 12.9 ± 2.6), CD11b (67.3 ± 3.8 vs 14.0 ± 2.0) and CD14 (83.0 ± 5.7 vs 8.0 ± 1.0) was significantly increased at day 4 compared with the control group (all P < 0.01). Cell cycle of the THP-1 cells was arrested in G(0)/G(1). Expression of the Annexin-V \[(32.5 ± 2.5)% vs (2.4 ± 0.3)%\] and caspase-3 \[(33.3 ± 2.5)% vs (3.6 ± 0.3)%\] was much higher than that in normal controls (all P < 0.01), and apoptosis was observed in THP-1 cells at day 5. Expression of p-Akt (0.24 ± 0.06 vs 1.20 ± 0.15), p-ERK (0.32 ± 0.05 vs 1.24 ± 0.09), and bcl-2 (0.11 ± 0.05 vs 0.65 ± 0.07) was much lower than that of the controls (all P < 0.01), while p27kip1 (1.08 ± 0.09 vs 0.10 ± 0.02) was significantly increased at day 4 (P < 0.05). CONCLUSION: Anti-CD44 antibody can induce the differentiation and apoptosis of THP-1 cell through inhibiting PI3K/AKt and ERK1/2 signaling pathway.

[Effect of rapamycin on apoptosis in human myelodysplastic syndrome cell line MUTZ-1 and its possible mechanisms].

The aim of this study was to investigate the effect of rapamycin on cell growth and apoptosis in the myelodysplastic syndrome (MDS) cell line MUTZ-1 and possible mechanism. MUTZ-1 cells were treated with rapamycin, cell proliferation capability was determined with MTT, protein expression including Annexin V/PI, caspase 3, PTEN, p-Akt, p-mTOR and the cell cycle were analyzed with flow cytometry. The results indicated that the proliferation of MUTZ-1 cells was inhibited by rapamycin in concentration-and time-dependent manners (r=0.67, 0.61, 0.72). After treatment with rapamycin for 24-72 hours, cell count in G0/G1 were significantly higher than that of the control (p<0.01), and this effect showed a time-and concentration-dependency (r=0.94, 0.93, 0.92), the cell cycle was blocked in G0/G1 phase. As compared with control group, the proportion of Annexin V+PI-MUTZ-1 cells and the cellular PTEN levels increased in the treated group dramatically and in time-and dose-dependent manners (p<0.01). To the contrary, level of p-mTOR expression markedly decreased as compared with control group (p<0.05). It is concluded that the rapamycin inhibits the proliferation of MUTZ-1 cells, down-regulates the PTEN/PI3K-Akt/mTOR signaling pathway by interaction with mTOR, which induces the apoptosis of mUTZ-1 cells.

[Study on platelet activated state and platelet activated function in adults with acute leukemia].

To investigate the changes of platelet activated state and platelet activated function by trace whole blood flow cytometry (FCM), and to explore the mechanism of hemorrhage and infiltration in adults with acute leukemia, the expression percentage and changes of these expressions of CD62p and PAC-1 on platelet surface were determined by FCM of trace whole blood after platelet activated by ADP in patients with new diagnosed AL (group I), complete remission (CR, group II) and continuously complete remission (CCR, group III). Healthy adults were used as control group. The result showed that the expression of CD62p in group I and II was higher than that in control group, before and after platelet activated by ADP (P < 0.01). The expression of PAC-1 in group I was higher than that in control group (P < 0.01), the expression of PAC-1 in group II was lower than that in control group (P > 0.01), There was no significant difference in expression of CD62p and PAC-1 between group III and control group (P > 0.01), and no significant difference was found between AL group with megakaryocyte malignant pathological changes and AL group without megakaryocyte malignant pathological changes before platelet activated by ADP (P > 0.01). After platelet activated by ADP, the expression of PAC-1 in the former was lower than that in the latter (P < 0.01). It is concluded that (1) high level activated platelet in peripheral blood of AL patients show that interaction between activated platelet and leukemia cells can be one of reason resulting in widespread hemorrhage and infiltration AL patiens; (2) the decrease of number and activted function of platelet at the first stage of AL patients may be caused by malignant hyperplasia of leukemia cells and damage of megakaryopoiesis in bone marrow.

[Study on NB4 cell apoptosis induced by trichosanthin].

In order to study the influence of trichosanthin (TCS) on apoptosis and growth inhibition of human NB4 cells in vitro, the expression of annexin V and the change of DeltaPsim of NB4 cells induced by TCS was analyzed by FACS, and MTT assay was adopted to measure the growth inhibition ratio of NB4 cells treated with TCS. Apoptosis was assayed by agarose gel electrophoresis. The results showed the higher concentration of TCS and the longer the acting time, the stronger growth inhibition of NB4 cells. The expression of annexin V was positive, and the positive ratio was greatly enhanced with prolongation of acting time. DeltaPsim reduced gradually while the apoptosis cells increasing. DNA agarose gel electrophoresis showed a gradient, which confirmed that TCS could induce NB4 cells apoptosis. In conclusion, taken together, data show that TCS can inhibit NB4 growth in vitro, and induce apoptosis. Experiment provides an important evidence for application of TCS in clinical treatment of acute promyelocytic leukemia.