METTL3 affects FLT3-ITD+ acute myeloid leukemia by mediating autophagy by regulating PSMA3-AS1 stability.

The study was designed to explore the role of PSMA3-AS1 in initiation and progression of acute myeloid leukemia (AML) and investigate its action mechanism. Expression of PSMA3-AS1, miR-20a-5p and ATG16L1 both in vitro and in vivo was measured by qRT-PCR. The expression of protein was detected by western blot assay. Edu staining and flow cytometry were utilized to measure cell proliferation and apoptosis. Potential target was predicted by bioinformatics and was verified by dual-luciferase report gene assay and RNA pull down assay. QRT-PCR was used to quantify autophagy (LC3, Beclin1, P62) related genes. The m6A modification test is used to verify the effect of METTL3 on PSMA3-AS1. Tumor model was used to identify the effect of PSMA3-AS1 on tumor growth in vivo, and immunohistochemistry was applied to detect expression of ki67 and TUNEL. The results indicate that PSMA3-AS1 was upregulated in FLT3-ITD+ AML patients. Si-PSMA3-AS1 could inhibit the proliferation, autophagy and promote the apoptosis in MV4-11 and Molm13 cells. METTL3 could enhance the PSMA3-AS1 RNA stability. In addition, this study revealed that PSMA3-AS1 affected FLT3-ITD+ AML by targeting expression of miR-20a-5p, and miR-20a-5p further modulated expression of ATG16L1, an mRNA that down-regulated in AML, to affect disease advancement. PSMA3-AS1 could promote FLT3-ITD+ AML progression by regulating the level of autophagy through miR-20a-5p/ATG16L1 pathway. In addition, the increase of PSMA3-AS1 may be caused by the involvement of METTL3 in regulating its stability. This discovery will provide new horizons for early screening and targeted therapy of FLT3-ITD+ AML.

Hes1 Controls Proliferation and Apoptosis in Chronic Lymphoblastic Leukemia Cells by Modulating PTEN Expression.

Hairy and enhancer of split homolog-1 (HES1), regulated by the Notch, has been reported to play important roles in the immune response and cancers, such as leukemia. In this study, we aim to explore the effect of HES1-mediated Notch1 signaling pathway in chronic lymphocytic leukemia (CLL). Reverse transcription quantitative polymerase chain reaction and Western blot assay were conducted to determine the expression of HES1, Notch1, and PTEN in B lymphocytes of peripheral blood samples of 60 CLL patients. We used lentivirus-mediated overexpression or silencing of HES1 and the Notch1 signaling pathway inhibitor, MW167, to detect the interaction among HES1, Notch1, and PTEN in CLL MEC1 and HG3 cells. MTT assay and flow cytometry were employed for detection of biological behaviors of CLL cells. HES1 and Notch1 showed high expression, but PTEN displayed low expression in B lymphocytes of peripheral blood samples of patients with CLL in association with poor prognosis. HES1 bound to the promoter region of PTEN and reduced PTEN expression. Overexpression of HES1 activated the Notch1 signaling pathway, thus promoting the proliferation of CLL cells, increasing the proportion of cells arrested at the S phase and limiting the apoptosis of CLL cells. Collectively, HES1 can promote activation of the Notch1 signaling pathway to cause PTEN transcription inhibition and the subsequent expression reduction, thereby promoting the proliferation and inhibiting the apoptosis of CLL cells.

Effect of EPA on Hsp90 and GRα protein expression in multiple myeloma drug-resistant cells.

BACKGROUND: Approximately 20% of MM patients harbor glucocorticoid (GC) resistance and are not responsive to therapeutic effect. Chaperoneheat-shock proteins Hsp90 is needed for ligand docking, The imbalance of Hsp90/GRα (glucocorticoid receptor α) may be an important cause of GC resistance. Recent studies have indicated that EPA could repress cancer cell growth by regulating critical influential factors in progression of cancer, consisting of resistance to drugs, chemosensitivity. The aim of the present study was to test the cytotoxic effects of EPA alone or EPA + Dexamethasone in dexamethasone-resistant MM cell (MM.1R) and investigate whether DHA can induce apoptosis and reverse acquired glucocorticoid resistance in dexamethasone-resistant MM cell (MM.1R). METHODS: Cell Counting Kit-8 (CCK-8) was used to detect the proliferation of MM.1R cells after treating with EPA alone and EPA combined with DEX. Mitochondrial membrane potential was measured by flow cytometry and GRα and Hsp90 protein expression were assessed by western blot analysis. RESULTS: EPA alone was able to inhibit cell proliferation as evidenced by CCK-8 assay and the tumor growth was remarkably suppressed by EPA + Dexamethasone, Cell apoptosis after EPA treatment was obviously observed by Flow cytometry analysis of the mitochondrial membrane potential. Analysis of Hsp90 and GRα proteins in MM.1R cells incubated with EPA revealed down-regulation of Hsp90 and up-regulation of GRα. Accordingly, the Hsp90/GRα ratio was significantly decreased with the increase of EPA concentration. CONCLUSIONS: EPA might be used as a new effective treatment for reversal of glucocorticoid-resistance in multiple myeloma.

Inhibition of Histone Deacetylase 6 by Tubastatin A Attenuates the Progress of Osteoarthritis via Improving Mitochondrial Function.

Because chondrocytes are the only resident cells in articular cartilage, the steady state of these cells is important for the maintenance of joint function. In various osteoarthritis diseases, chondrocytes undergo a series of pathophysiologic changes, leading to the loss of chondrocytes and the degradation of extracellular matrix (ECM). This study found that Cytoplasmic localized histone deacetylase 6 (HDAC6) is up-regulated on the articular surface in a destabilization of the medial meniscus-induced mouse osteoarthritis model. Because HDAC6 is highly related to the acetylation of tubulin and the function of the microtubule system is closely related to material transport and signal transduction, the relationship between the expression level or activity of HDAC6 and the fate of chondrocytes in vitro and in vivo were confirmed. Primary chondrocytes overexpressing DNA-HDAC6 with plasmid were constructed in vitro, and HDAC6 inhibitor Tubastatin A was selected to inhibit HDAC6 enzyme activity in vivo and in vitro. Subsequently, mitochondrial spatial arrangement, degradation of ECM, and pathological changes in joint were defined. The results indicate that overexpression of HDAC6 causes mitochondrial dysfunction and promotes reactive oxygen species production, leading to degradation of ECM. Tubastatin A treatment after osteoarthritis ameliorates the degradation of cartilage and improves the microenvironment and function of the joint. HDAC6 may be targeted to treat osteoarthritis.

Effects of hypoxia on differentiation of menstrual blood stromal stem cells towards tenogenic cells in a co-culture system with Achilles tendon cells.

Achilles tendons have a very poor capacity for intrinsic regeneration. The cell-based treatment strategy for Achilles tendinitis includes the application of mesenchymal stem cells (MSCs), which have high proliferative and multipotent differentiation ability, and is a promising approach. The aim of the present study was to explore the tenogenic potential of human menstrual blood stromal stem cells (MenSCs) in a co-culture system and to compare the tenogenic capability under normoxic and hypoxic conditions. MenSCs were co-cultured indirectly with Achilles tendon cells in a Transwell co-culture system for 1, 2, or 3 weeks in two different concentrations of oxygen (20 and 2% O2), whereas the control contained only MenSCs. The extracellular matrix of MenSCs in each system was evaluated by Alcian blue staining assay, histological staining, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and western blot analysis. Alcian blue staining assay revealed a significant increase (P<0.05) in proteoglycan secretion by the differentiated MenSCs. Identical results were obtained by RT-qPCR for collagen I, which was validated by western blot analysis. Considerably increased collagen I and collagen III gene expression levels were exhibited by cells in the co-culture treatment group when compared with the control (P<0.05); however, no significant difference was detected between the normoxic (20% O2) and hypoxic treatment (2% O2) groups. RT-qPCR was utilized to determine the expression levels of thrombospondin 4, scleraxis and tenascin C in the differentiated MenSCs; a significant increase in the expression of these specific genes was indicated in the co-culture treatment group compared with the control (P<0.05). Although the expression levels were markedly higher in hypoxia than in normoxia conditions, this difference was not significant. To conclude, the present study indicated that MenSCs manifested a strong proliferative and multipotent capacity for differentiation and differentiated into Achilles tenogenic cells. Therefore, the use of MenSCs may be considered in Achilles tendinitis therapy.

Overexpression of long non-coding RNA HOTAIR predicts a poor prognosis in patients with acute myeloid leukemia.

The long non-coding RNA, HOX transcript antisense intergenic RNA (HOTAIR), has been indicated to have involvement in a number of cancers, however, its role in acute myeloid leukemia (AML) is unknown. The present study aimed to investigate the pattern of HOTAIR expression in AML and to evaluate its clinical significance in tumor progression. Quantitative polymerase chain reaction was performed to examine the HOTAIR expression in mononuclear cells from the bone marrow (BM) or peripheral blood specimens of 85 patients with newly diagnosed AML. The association of HOTAIR expression with the clinicopathological factors and prognosis of AML patients was statistically analyzed. The expression of HOTAIR was significantly upregulated in the AML patients compared with the healthy controls (mean expression value, 3.87±0.29 vs. 1.28±0.09; P<0.001), and markedly decreased in the patients post-treatment compared with pre-treatment (4.76±0.47 vs. 2.81±0.27; P<0.001). Moreover, high levels of HOTAIR were associated with higher white blood cell and BM blast counts (P<0.001 and P=0.001, respectively), and lower hemoglobin and platelet counts (P=0.007 and 0.001, respectively). Patients with a high level of HOTAIR expression had relatively poor overall survival (OS; 20.5 vs. 32.1 months, P=0.001) and relapse-free survival (21.5 vs. 33.6 months, P=0.001) times compared with those with a low level of HOTAIR expression. These data demonstrated that HOTAIR expression was upregulated in newly diagnosed AML patients and was associated with leukemic burden, and DFS and OS times. HOTAIR may represent a biomarker of a poor prognosis and is a potential therapeutic target for AML treatment.

Subcutaneous Administration of Bortezomib in Combination with Thalidomide and Dexamethasone for Treatment of Newly Diagnosed Multiple Myeloma Patients.

OBJECTIVE: To investigate the efficacy and safety of the treatment of the newly diagnosed multiple myeloma (MM) patients with the therapy of subcutaneous (subQ) administration of bortezomib and dexamethasone plus thalidomide (VTD) regimen. METHODS: A total of 60 newly diagnosed MM patients were analyzed. 30 patients received improved VTD regimen (improved VTD group) with the subQ injection of bortezomib and the other 30 patients received conventional VTD regimen (VTD group).The efficacy and safety of two groups were analyzed retrospectively. RESULTS: The overall remission (OR) after eight cycles of treatment was 73.3% in the VTD group and 76.7% in the improved VTD group (P > 0.05). No significant differences in time to 1-year estimate of overall survival (72% versus 75%, P = 0.848) and progression-free survival (median 22 months versus 25 months; P = 0.725) between two groups. The main toxicities related to therapy were leukopenia, neutropenia, thrombocytopenia, asthenia, fatigue, and renal and urinary disorders. Grade 3 and higher adverse events were significantly less common in the improved VTD group (50%) than VTD group (80%, P = 0.015). CONCLUSIONS: The improved VTD regimen by changing bortezomib from intravenous administration to subcutaneous injection has noninferior efficacy to standard VTD regimen, with an improved safety profile and reduced adverse events.

Adiponectin signals through Adiponectin Receptor 1 to reverse imatinib resistance in K562 human chronic myeloid leukemia cells.

Adiponectin, a member of adipokines, is a functional ligand for Adiponectin Receptor-1 (AdipoR1) and Adiponectin Receptor-2 (AdipoR2), and has been found to be linked to the risk of CML. Imatinib has undoubtedly revolutionised the management and outcome of chronic myeloid leukemia (CML), however imatinib resistance has been recognized as a major problem in CML therapy. In this study, we first established imatinib-resistant K562 CML cells, and then evaluated the effect of Adiponectin in reversing imatinib resistance. The data presented here demonstrated that Adiponectin was able to reverse K562 resistance to imatinib in vitro and in vivo. Additional data with molecular approaches suggested that the reversion of Adiponectin in imatinib resistance signals through AdipoR1 but not AdipoR2 to downregulate Bcr-Abl expression and effect in imatinib-resistant K562 CML cells. Taken together, our data showed that Adiponectin can reverse imatinib resistance in CML, and to a certain extent elucidate the mechanism of Adiponectin reversing imatinib resistance that may provide a new and promising approach in imatinib resistance management in CML therapy.