Targeting PI3K/AKT/mTOR network for treatment of leukemia

Boric Acid Affects Cell Proliferation, Apoptosis, and Oxidative Stress in ALL Cells

T-cell acute lymphoblastic leukemia (T-ALL) is a type of acute lymphoblastic leukemia from early T-cell progenitors. Interest grows in creating less toxic agents and therapies for chemo-resistant T-ALL cancer. Recently, elemental boron has special properties useful in the creation of new drugs. Studies have revealed the cytotoxic properties of boric acid (BA) on cancer, but not fully understood. We aimed to investigate the effect of BA on cell proliferation, apoptosis, and oxidative stress in the Jurkat cells. The effects of BA on cell viability were determined by 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay for 24-48-72 h. The impact of BA on apoptosis was analyzed by acridine orange/ethidium bromide. Expression of apoptosis regulatory genes (Bcl-2, Bax, Caspase-3-8-9) and apoptotic miRNA (miR-21) was used by real-time quantitative polymerase chain reaction (RT-qPCR). The total oxidant status (TOS), total antioxidant status (TAS), and the oxidative stress index (OSI) value were calculated for oxidative stress. We determined the cytotoxic activity of BA on Jurkat cells by using XTT and defined the IC50 concentration (802.7 μg/mL) of BA. The findings clearly show that BA inhibited Jurkat cell proliferation dose-dependently. BA induced apoptosis through downregulated anti-apoptotic genes, and upregulated pro-apoptotic genes. Additionally, we found that BA significantly reduced the expression of miR-21 (p<0.001). Our findings demonstrated that different doses of BA increased TAS levels while decreasing TOS levels in Jurkat cells. Our study suggests that BA might be potential anti-cancer agent candidate in ALL via inhibition of cell proliferation, induced apoptosis, and reducing the amounts of anti-oxidants in cells.

Aberrant METTL14 gene expression contributes to malignant transformation of benzene-exposed myeloid cells

Benzene is a known contributor to human leukaemia through its toxic effects on bone marrow cells, and epigenetic modification is believed to be a potential mechanism underlying benzene pathogenesis. However, the specific roles of N6-methyladenosine (m6A), a newly discovered RNA post-transcriptional modification, in benzene-induced hematotoxicity remain unclear. In this study, we identified self-renewing malignant proliferating cells in the bone marrow of benzene-exposed mice through in vivo bone marrow transplantation experiments and Competitive Repopulation Assay. Subsequent analysis using whole transcriptome sequencing and RNA m6A methylation sequencing revealed a significant upregulation of RNA m6A modification levels in the benzene-exposed group. Moreover, RNA methyltransferase METTL14, known as a pivotal player in m6A modification, was found to be aberrantly overexpressed in Lin-Sca-1+c-Kit+ (LSK) cells of benzene-exposed mice. Further analysis based on the GEO database showed a positive correlation between the expression of METTL14, mTOR, and GFI and benzene exposure dose. In vitro cellular experiments, employing experiments such as western blot, q-PCR, m6A RIP, and CLIP, validated the regulatory role of METTL14 on mTOR and GFI1. Mechanistically, continuous damage inflicted by benzene exposure on bone marrow cells led to the overexpression of METTL14 in LSK cells, which, in turn, increased m6A modification on the target genes' (mTOR and GFI1) RNA. This upregulation of target gene expression activated signalling pathways such as mTOR-AKT, ultimately resulting in malignant proliferation of bone marrow cells. In conclusion, this study offers insights into potential early targets for benzene-induced haematologic malignant diseases and provides novel perspectives for more targeted preventive and therapeutic strategies.

Licochalcone A induces mitochondria-dependent apoptosis and interacts with venetoclax in acute myeloid leukemia

The management of patients with acute myeloid leukemia (AML) remains a challenge because of the complexity and heterogeneity of this malignancy. Despite the recent approval of several novel targeted drugs, resistance seems inevitable, and clinical outcomes are still suboptimal. Increasing evidence supports the use of natural plants as an important source of anti-leukemic therapeutics. Licochalcone A (LCA) is an active flavonoid isolated from the roots of licorice, Glycyrrhiza uralensis Fisch., possessing extensive anti-tumor activities. However, its effects on AML and the underlying mechanisms remain unknown. Here, we showed that LCA decreased the viability of established human AML cell lines in a dose- and time-dependent manner. LCA significantly induced mitochondrial apoptotic cell death, accompanied by the downregulation of MCL-1, upregulation of BIM, truncation of BID, and cleavage of PARP. A prominent decline in the phosphorylation of multiple critical molecules, including AKT, glycogen synthase kinase-3β (GSK3β), ERK, and P38 was observed upon LCA treatment, indicating PI3K and MAPK signals were suppressed. Both transcription and translation of c-Myc were also inhibited by LCA. In addition, LCA enhanced the cytotoxicity of the BCL-2 inhibitor venetoclax. Furthermore, the anti-survival and pro-apoptotic effects were confirmed in primary blasts from 10 patients with de novo AML. Thus, our results expand the applications of LCA, which can be regarded as a valuable agent in treating AML.

B cell receptor signaling and associated pathways in the pathogenesis of chronic lymphocytic leukemia

B cell antigen receptor (BCR) signaling is a key driver of growth and survival in both normal and malignant B cells. Several lines of evidence support an important pathogenic role of the BCR in chronic lymphocytic leukemia (CLL). The significant improvement of CLL patients' survival with the use of various BCR pathway targeting inhibitors, supports a crucial involvement of BCR signaling in the pathogenesis of CLL. Although the treatment landscape of CLL has significantly evolved in recent years, no agent has clearly demonstrated efficacy in patients with treatment-refractory CLL in the long run. To identify new drug targets and mechanisms of drug action in neoplastic B cells, a detailed understanding of the molecular mechanisms of leukemic transformation as well as CLL cell survival is required. In the last decades, studies of genetically modified CLL mouse models in line with CLL patient studies provided a variety of exciting data about BCR and BCR-associated kinases in their role in CLL pathogenesis as well as disease progression. BCR surface expression was identified as a particularly important factor regulating CLL cell survival. Also, BCR-associated kinases were shown to provide a crosstalk of the CLL cells with their tumor microenvironment, which highlights the significance of the cells' milieu in the assessment of disease progression and treatment. In this review, we summarize the major findings of recent CLL mouse as well as patient studies in regard to the BCR signalosome and discuss its relevance in the clinics.

Key candidate genes and pathways in T lymphoblastic leukemia/lymphoma identified by bioinformatics and serological analyses

T-cell acute lymphoblastic leukemia (T-ALL)/T-cell lymphoblastic lymphoma (T-LBL) is an uncommon but highly aggressive hematological malignancy. It has high recurrence and mortality rates and is challenging to treat. This study conducted bioinformatics analyses, compared genetic expression profiles of healthy controls with patients having T-ALL/T-LBL, and verified the results through serological indicators. Data were acquired from the GSE48558 dataset from Gene Expression Omnibus (GEO). T-ALL patients and normal T cells-related differentially expressed genes (DEGs) were investigated using the online analysis tool GEO2R in GEO, identifying 78 upregulated and 130 downregulated genes. Gene Ontology (GO) and protein-protein interaction (PPI) network analyses of the top 10 DEGs showed enrichment in pathways linked to abnormal mitotic cell cycles, chromosomal instability, dysfunction of inflammatory mediators, and functional defects in T-cells, natural killer (NK) cells, and immune checkpoints. The DEGs were then validated by examining blood indices in samples obtained from patients, comparing the T-ALL/T-LBL group with the control group. Significant differences were observed in the levels of various blood components between T-ALL and T-LBL patients. These components include neutrophils, lymphocyte percentage, hemoglobin (HGB), total protein, globulin, erythropoietin (EPO) levels, thrombin time (TT), D-dimer (DD), and C-reactive protein (CRP). Additionally, there were significant differences in peripheral blood leukocyte count, absolute lymphocyte count, creatinine, cholesterol, low-density lipoprotein, folate, and thrombin times. The genes and pathways associated with T-LBL/T-ALL were identified, and peripheral blood HGB, EPO, TT, DD, and CRP were key molecular markers. This will assist the diagnosis of T-ALL/T-LBL, with applications for differential diagnosis, treatment, and prognosis.

Targeting PI3K/AKT/mTOR and MAPK Signaling Pathways in Gastric Cancer

Gastric cancer (GC) is the fourth leading cause of death worldwide, with more than 1 million cases diagnosed every year. Helicobacter pylori represents the main risk factor, being responsible for 78% of the cases. Increased amounts of salt, pickled food, red meat, alcohol, smoked food, and refined sugars negatively affect the stomach wall, contributing to GC development. Several gene mutations, including PIK3CA, TP53, ARID1A, CDH1, Ras, Raf, and ERBB3 are encountered in GC pathogenesis, leading to phosphatidylinositol 3-kinase (PI3K) protein kinase B (AKT)/mammalian target of rapamycin (mTOR)-PI3K/AKT/mTOR-and mitogen-activated protein kinase (MAPK) signaling pathway activation and promoting tumoral activity. Helicobacter pylori, growth factors, cytokines, hormones, and oxidative stress also activate both pathways, enhancing GC development. In clinical trials, promising results have come from monoclonal antibodies such as trastuzumab and ramucirumab. Dual inhibitors targeting the PI3K/AKT/mTOR and MAPK signaling pathways were used in vitro studies, also with promising results. The main aim of this review is to present GC incidence and risk factors and the dysregulations of the two protein kinase complexes together with their specific inhibitors.

Long non-coding RNA small nucleolar RNA host gene 29 drives chronic myeloid leukemia progression via microRNA-483-3p/Casitas B-lineage Lymphoma axis-mediated activation of the phosphoinositide 3-kinase/Akt pathway

The aberrant expression of the long non-coding RNA (lncRNA) Small Nucleolar RNA Host Gene 29 (SNHG29) has been associated with various human cancers. However, the role of SNHG29 in chronic myeloid leukemia (CML) remains elusive. Therefore, this study aimed to investigate the function of SNHG29 in CML and unveil its potential underlying mechanisms. Herein, peripheral blood samples from 44 CML patients and 17 healthy subjects were collected. The expressions of SNHG29, microRNA-483-3p (miR-483-3p), and Casitas B-lineage Lymphoma (CBL) were measured using quantitative polymerase chain reaction (qPCR) or Western Blot. Cell viability, apoptosis, and cell cycle progression were evaluated using the Cell Counting Kit-8 assay, 5-ethynyl-2'-deoxyuridine incorporation, and flow cytometry, respectively. Western Blot analysis was employed to assess protein expressions related to cellular proliferation, apoptosis, and oncogenesis. RNA immunoprecipitation and dual-luciferase reporter assays were utilized to verify the interactions among SNHG29, miR-483-3p, and CBL. SNHG29 was significantly overexpressed in both blood samples of CML patients and CML cell lines. In CML, increased expression of SNHG29 was positively correlated with clinical staging, and patients with high SNHG29 expression had poorer survival outcomes. Functionally, knocking down SNHG29 effectively inhibited CML cell proliferation and promoted apoptosis. Mechanistically, SNHG29 acted as a competing endogenous RNA for miR-483-3p to modulate CBL expression, thereby activating the Phosphoinositide 3-Kinase/Akt signaling pathway and mediating CML progression. In summary, these findings reveal that SNHG29 promotes tumorigenesis in CML, offering a potential therapeutic strategy for CML treatment.

The role and mechanism of AZD5363 anti-leukemia activity in T-cell acute lymphoblastic leukemia

BACKGROUND

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive and heterogeneous hematologic malignancy. Chemotherapy resistance and refractory relapses are the most important challenges in T-ALL. PI3K/Akt/mTOR pathway has been implicated in regulating cell survival, T-ALL development and resistance to chemotherapy. We explored the effects of AZD5363 (a potent pan-Akt inhibitor) alone and in combination with autophagy inhibitor hydroxycholoroquine sulfate (HCQ) in cultured CCRF-CEM, Jurkat and PF382 cells and a T-ALL xenograft mouse model.

METHODS

A xenograft mouse model was used to investigate the effect of AZD5363 on T-ALL progression. MTT assay, flow cytometry, siRNA, transmission electron microscopy and western blotting were performed in cultured CCRF-CEM, Jurkat and PF382 cells. The interaction between AZD5363 and HCQ was explored by molecular docking.

RESULTS

AZD5363 delayed T-ALL progression and increased the expression of cleaved caspase-3 and LC3B-II in mice. AZD5363 decreased cells viability by arresting cell cycle in the G1 phase and inducing apoptosis, and, significantly increased the number of autophagosomes (p < 0.01). The increased expression of cleaved caspase-3 and LC3B-II, and phosphorylation of Akt and mTOR were significantly, inhibited by AZD5363. HCQ blocked AZD5363-induced autophagy and enhanced AZD5363-induced cell death (p < 0.01).

CONCLUSIONS

AZD5363 suppressed T-ALL progression and its anti-leukemia activity was enhanced by HCQ in T-ALL cells, which might provide a potential therapeutic strategy for human T-ALL.

Overcoming adaptive resistance in AML by synergistically targeting FOXO3A-GNG7-mTOR axis with FOXO3A inhibitor Gardenoside and rapamycin

Therapeutic targeting FOXO3A (a forkhead transcription factor) represents a promising strategy to suppress acute myeloid leukemia (AML). However, the effective inhibitors that target FOXO3A are lacking and the adaptive response signaling weakens the cytotoxic effect of FOXO3A depletion on AML cells. Here, we show that FOXO3A deficiency induces a compensatory response involved in the reactive activation of mTOR that leads to signaling rebound and adaptive resistance. Mitochondrial metabolism acts downstream of mTOR to provoke activation of JNK/c-JUN via reactive oxygen species (ROS). At the molecular level, FOXO3A directly binds to the promoter of G protein gamma subunit 7 (GNG7) and preserves its expression, while GNG7 interacts with mTOR and restricts phosphorylated activation of mTOR. Consequently, combinatorial inhibition of FOXO3A and mTOR show a synergistic cytotoxic effect on AML cells and prolongs survival in a mouse model of AML. Through a structure-based virtual screening, we report one potent small-molecule FOXO3A inhibitor (Gardenoside) that exhibits a strong effect of anti-FOXO3A DNA binding. Gardenoside synergizes with rapamycin to substantially reduce tumor burden and extend survival in AML patient-derived xenograft model. These results demonstrate that mTOR can mediate adaptive resistance to FOXO3A inhibition and validate a combinatorial approach for treating AML.

Phenytoin regulates osteogenic differentiation of human bone marrow stem cells by PI3K/Akt pathway

Background

We mainly studied the mechanism by which phenytoin promotes osteogenic differentiation of human jawbone marrow stem cells.

Methods

Bone marrow stem cells were extracted from jaw bone tissue debris obtained from 5 subjects undergoing implant restoration. Osteogenic and adipogenic experiments proved cells stemness, and the expression of ALP, RUNX2, and OSX were detected by qPCR and Western blot. High-throughput sequencing was used to extract differentially expressed genes, the network database predicted phenytoin drug targets, GO and KEGG enrichment combined with PPI network diagram to analyze the osteogenesis mechanism.

Results

Calcium nodules and lipid droplet formation were observed in osteogenic and adipogenic experiments. The concentration of phenytoin within 100 mg/L does not produce cytotoxicity. The results of PCR and WB indicated that 50 mg/L phenytoin significantly promoted the expression of ALP and RUNX2, and 25 mg/L phenytoin significantly promoted the expression of OSX. The results of network pharmacology suggest that phenytoin promotes bone formation by up-regulating FGFR2, S1PR1, TGFB3, VCAN core proteins and activating PI3K/Akt pathway.

Conclusions

Phenytoin activated the PI3K/Akt pathway to regulate the osteogenic differentiation of human jawbone marrow stem cells. https://data.mendeley.com/datasets/t3xstktt93/1.

Phosphoinositide 3-kinase as a therapeutic target in angiogenic disease

Phosphoinositide 3-kinases (PI3Ks) generate lipids that control multitudinous intracellular cell signaling events which participate in cell survival and proliferation. In addition, PI3K signaling also contributes to metabolism, immunity, angiogenesis and cardiovascular homeostasis, and many diseases. The diverse actions of PI3K stem from the existence of their various isoforms and a variety of protein effectors. Hence, PI3K isoform-specific inhibitors have already achieved a wonderful effect on treating cancer. Herein, we summarize the molecular mechanism of PI3K inhibitors in preventing the permeability of vessels and neovascularization. Additionally, we briefly illustrate how PI3K signaling modulates blood vessel growth and discuss the different roles that PI3K isoforms play in angiogenesis.

CXCR2 inhibition overcomes ponatinib intolerance by eradicating chronic myeloid leukemic stem cells through PI3K/Akt/mTOR and dipeptidylpeptidase Ⅳ (CD26)

This study explores the therapeutic potential of targeting CXCR2 in patients afflicted with ponatinib-resistant chronic myeloid leukemia (CML). Ponatinib, a third-generation tyrosine kinase inhibitor (TKI), was initially designed for treating patients with CML harboring the T315I mutation. However, resistance or intolerance issues may lead to treatment discontinuation. Additionally, TKIs have exhibited limitations in eradicating quiescent CML stem cells. Our investigation reveals the activation of CXC chemokine receptor 2 (CXCR2) signaling in response to chemotherapeutic stress. Treatment with the CXCR2 antagonist, SB225002, effectively curtails cell proliferation and triggers apoptosis in ponatinib-resistant CML cells. SB225002 intervention also results in the accumulation of reactive oxygen species and disruption of mitochondrial function, phenomena associated with TKI chemoresistance and apoptosis. Furthermore, we demonstrate that activated CXCR2 expression induces the activity of dipeptidylpeptidase Ⅳ (DPP4/CD26), a CML leukemic stem cell marker, and concomitantly inhibits the PI3K/Akt/mTOR pathway cascades. These findings underscore the novel role of CXCR2 in the regulation of not only ponatinib-resistant CML cells, but also CML leukemic stem cells. Consequently, our study proposes that targeting CXCR2 holds promise as a viable therapeutic strategy for addressing patients with CML grappling with ponatinib resistance.

Prognostic value and therapeutic targeting of XPO1 in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is a subtype of B-cell malignancy with high heterogeneity. XPO1 is highly expressed in many hematological malignancies, which predicts poor prognosis. In the study, we aimed to explore the prognostic role of XPO1 and the therapeutic effect of Selinexor, a selective inhibitor of nuclear export, which targets XPO1. We collected 200 CLL samples in our center to confirm XPO1 mRNA expression and analyzed the correlation between XPO1 expression and prognosis. Then, we decreased XPO1 expression with Selinexor to explore the effect of proliferation inhibition, cell cycle arrest, and apoptosis in CLL cell lines. RNA-Seq was performed to explore potential mechanisms. We analyzed XPO1 expression in a cohort of 150 treatment naive patients and another cohort of 50 relapsed and refractory (R/R) patients and found that XPO1 expression was upregulated in 76% of CLL patients compared with healthy donors. Survival analysis suggested that patients with increased XPO1 expression had inferior treatment-free survival (P = 0.022) and overall survival (P = 0.032). The inhibitor of XPO1, Selinexor, induced apoptosis in primary CLL cells. We showed the effects of Selinexor on proliferation inhibition, cell cycle arrest, and apoptosis in CLL cell lines with JVM3, MEC1, and ibrutinib-resistant (MR) cells via nuclear retention of cargo proteins of IκBα, p65, p50, and FOXO3a. Moreover, downregulation of the NF-κB and FOXO pathways was a common feature of the three CLL cell lines responding to Selinexor, indicating the potential application of XPO1 inhibitor even in the high-risk CLL cells. We identified XPO1 as an unfavorable prognostic factor for CLL patients and provided a rationale for further investigation of the clinically XPO1 targeted therapeutic strategy against CLL.

Targeted delivery of AZD5363 to T-cell acute lymphocytic leukemia by mSiO2-Au nanovehicles

T-cell acute lymphocytic leukemia (T-ALL) is the most common cancer in children, with a low survival rate because of drug resistance and a high recurrence rate. Targeted delivery of chemotherapy drugs can reduce their side effects and improve their efficacy. The abnormality of phosphatidylinositol-3-kinase/protein kinase B/ mammalian target of rapamycin (PI3K/Akt/mTOR) pathway plays a key role in T-ALL occurrence. AZD5363 is a selective Akt inhibitor with promising therapeutic potential for tumors encoded by the PI3K/Akt/mTOR pathway. However, the toxicity and side effects have limited its application in treating T-ALL. This study aimed to design a delivery system for targeting AZD5363 to T-ALL by sgc8c aptamer designed as mesoporous silica (mSiO2) decorated with Au nanoparticles. The cell-specific targeting and cytotoxicity of mSiO2-Au-AZD5363-Apt were investigated. The mSiO2-Au nanovehicles were found feasible for AZD5363 delivery, with high loading efficiency and pH-responsive release in the acidic lysosome. More importantly, mSiO2-Au-AZD5363-Apt nanovehicles could specifically recognize and enter T-ALL cells in vitro and in vivo, effectively inhibiting the proliferation of CCRF-CEM cells. In conclusion, mSiO2-Au-AZD5363-Apt provided an effective therapeutic method for the targeted treatment of T-ALL.

Regulation of Eukaryotic Translation Initiation Factor 4E as a Potential Anticancer Strategy

Eukaryotic translation initiation factors (eIFs) are highly expressed in cancer cells, especially eIF4E, the central regulatory node driving cancer cell growth and a potential target for anticancer drugs. eIF4E-targeting strategies primarily focus on inhibiting eIF4E synthesis, interfering with eIF4E/eIF4G interactions, and targeting eIF4E phosphorylation and peptide inhibitors. Although some small-molecule inhibitors are in clinical trials, no eIF4E inhibitors are available for clinical use. We provide an overview of the regulatory mechanisms of eIF4E and summarize the progress in developing and discovering eIF4E inhibitor strategies. We propose that interference with eIF4E/eIF4G interactions will provide a new perspective for the design of eIF4E inhibitors and may be a preferred strategy.

SIRT2 inhibitor SirReal2 enhances anti-tumor effects of PI3K/mTOR inhibitor VS-5584 on acute myeloid leukemia cells

BACKGROUND

Acute myeloid leukemia (AML) is a highly aggressive form of cancer that is frequently diagnosed in adults and small molecule inhibitors have gained significant attention as a potential treatment option for AML.

METHODS

The up-regulated genes in AML were identified through bioinformatics analysis. Potential candidate agents were selected through pharmacogenomics analysis. Proteomic experiments were conducted to determine the molecular mechanism after inhibitor treatment. To evaluate drug synergy, both cellular functional experiments and an AML mouse model were used.

RESULTS

Through bioinformatics analysis, we conducted a screening for genes that are highly expressed in AML, which led to the identification of nine small-molecule inhibitors. Among these inhibitors, the PI3K/mTOR inhibitor VS-5584 demonstrated significant effectiveness in inhibiting AML cell proliferation at low concentrations. Further testing revealed that VS-5584 induced apoptosis and cycle arrest of AML cells in a dose- and time-dependent manner. Proteomics analysis showed significant changes in protein expression profiles of AML cells after VS-5584 treatment, with 287 proteins being down-regulated and 71 proteins being up-regulated. The proteins that exhibited differential expression were primarily involved in regulating the cell cycle and apoptosis, as determined by GO analysis. Additionally, KEGG analysis indicated that the administration of VS-5584 predominantly affected the P53 and SIRT2 signaling pathways. The use of SIRT2 inhibitor SirReal2 alongside VS-5584 caused a significant reduction in the half-maximal inhibitory concentration (IC50 ) of VS-5584 on AML cells. In vivo, experiments suggested that VS-5584 combined with SirReal2 suppressed tumor growth in the subcutaneous model and extended the survival rate of mice injected with tumor cells via tail vein.

CONCLUSIONS

Taken together, the PI3K/mTOR inhibitor VS-5584 was effective in suppressing AML cell proliferation. PI3K/mTOR inhibitor combined with SIRT2 inhibitor exhibited a synergistic inhibitory effect on AML cells. Our findings offer promising therapeutic strategies and drug candidates for the treatment of AML.

CircRNA-CIRH1A Promotes the Development of Osteosarcoma by Regulating PI3K/AKT and JAK2/STAT3 Signaling Pathways

Osteogenic sarcoma (OS), one of the mesenchymal tumors with a high degree of malignancy, mainly occurs in the metaphysis of the long bones and around the knee joints in children and adolescents. The poor diagnosis in patients with OS can be attributed to the lack of early clinical symptoms, although the growth of tumor mass gradually results in severe pain and systemic symptoms. The mechanisms underlying the pathogenesis of OS are not fully understood. Thus, identifying early diagnostic biomarkers and novel targets involved in the progression of OS is of critical significance in the management of OS. CircRNA is a class of non-coding RNAs characterized by the close-loop structure and increased stability, which are implicated in the regulation of cell proliferation, differentiation, migration, and apoptosis. Moreover, circRNAs also play significant roles in aging and chronic disorders, such as cancer and cardiovascular diseases. Accordingly, we reported the upregulation of circRNA-CIRH1A in OS tissues and cell lines. Silencing circRNA-CIRH1A in OS cell lines (U2OS, HOS, Saos-2, and MG-63) could inhibit the cell proliferation, invasion, migration, and apoptosis, which was also validated in xenograft tumorigenesis mouse model. We further demonstrated that circRNA-CIRH1A sponged miR-1276, which subsequently disrupted the effect of miR-1276 on PI3K/AKT and JAK2/STAT3 signaling pathways. Together, our study revealed the oncogenic role of circRNA-CIRH1A in OS, and identified miR-1276/ PI3K-AKT and JAK2-STAT3 signaling axis as the key downstream mediators of circRNA-CIRH1A.

The lncRNA expression profile signature of leukemia stem cells is altered upon PI3K/mTOR inhibition: an in vitro and in silico study

Genetic and/or epigenetic alterations in hematopoietic stem cells (HSCs) contribute to leukemia stem cell (LSC) formation. We aimed to identify alterations in the lncRNA expression profile signature of LSCs upon inhibition of PI3K/Akt/mTOR signaling, which provides selective advantages to LSCs. We also aimed to elucidate the potential interaction networks and functions of differentially expressed lncRNAs (DELs). We suppressed PI3K/Akt/mTOR signaling in LSC and HSC cell-lines by specific PI3K/mTOR dual-inhibitor (VS-5584) and confirmed the inhibition by antibody-array. We defined DELs by qRT-PCR. Increased SRA, ZEB2-AS1, antiPeg11, DLX6-AS, SNHG4, and decreased H19, PCGEM1, CAR-Intergenic-10, L1PA16, IGF2AS, and SNHG5 levels (|log2fold-change|>5) were strictly associated with PI3K/Akt/mTOR pathway inhibition in LSC. We performed in silico analyses for DELs. ZEB2-AS1 was found to be specifically expressed in normal bone marrow and predominantly lower in leukemic cell-lines. Three sub-clusters were identified for DELs and they were associated with "abnormality of multiple cell lineages in the bone marrow." DELs were most highly enriched for "glucuronidation" Reactome pathway and "ascorbate and aldarate metabolism" and "inositol phosphate metabolism" KEGG pathways. Transcription factors, MBD4, NANOG, PAX6, RELA, CEBPB, and CEBPA were predicted to be associated with the DEL profile. SRA was predicted to interact with CREB1, RARA, and PPARA. The possible DELs' targets were predicted to form six ontological groups, be highly enriched for phosphoprotein, and be involved in "PPAR signaling pathway" and "ChREBP regulation by carbohydrates and cAMP." These results will help to elucidate the roles of lncRNAs in the mechanisms that provide selective advantages to leukemia stem cells.

WDR54 exerts oncogenic roles in T-cell acute lymphoblastic leukemia

WDR54 has been recently identified as a novel oncogene in colorectal and bladder cancers. However, the expression and function of WDR54 in T-cell acute lymphoblastic leukemia (T-ALL) were not reported. In this study, we investigated the expression of WDR54 in T-ALL, as well as its function in T-ALL pathogenesis using cell lines and T-ALL xenograft. Bioinformatics analysis indicated high mRNA expression of WDR54 in T-ALL. We further confirmed that the expression of WDR54 was significantly elevated in T-ALL. Depletion of WDR54 dramatically inhibited cell viability and induced apoptosis and cell cycle arrest at S phase in T-ALL cells in vitro. Moreover, knockdown of WDR54 impeded the process of leukemogenesis in a Jurkat xenograft model in vivo. Mechanistically, the expression of PDPK1, phospho-AKT (p-AKT), total AKT, phospho-ERK (p-ERK), Bcl-2 and Bcl-xL were downregulated, while cleaved caspase-3 and cleaved caspase-9 were upregulated in T-ALL cells with WDR54 knockdown. Additionally, RNA-seq analysis indicated that WDR54 might regulate the expression of some oncogenic genes involved in multiple signaling pathways. Taken together, these findings suggest that WDR54 may be involved in the pathogenesis of T-ALL and serve as a potential therapeutic target for the treatment of T-ALL.

Effect of mir-92a-3p on hydroquinone induced changes in human lymphoblastoid cell cycle and apoptosis

Hydroquinone (HQ), one of the metabolites of benzene in humans, has significant hepatotoxic properties. Chronic exposure to HQ can lead to leukemia. In a previous study by this group, we constructed a model of malignant transformation of human lymphoblastoid cells (TK6) induced by chronic exposure to HQ with significant subcutaneous tumorigenic capacity in nude mice. miR-92a-3p is a tumor factor whose role in HQ-induced malignant transformation is not yet clear. In the present study, raw signal analysis and dual-luciferase reporter gene results suggested that miR-92a-3p could target and regulate TOB1, and the expression level of miR-92a-3p was significantly upregulated in the long-term HQ-induced TK6 malignant transformation model, while the anti-proliferative factor TOB1 was significantly downregulated. To investigate the mechanism behind this, we inhibited miR-92a-3p in a malignant transformation model and found a decrease in cell viability, a decrease in MMP-9 protein levels, a G2/M phase block in the cell cycle, and an upregulation of the expression of G2/M phase-related proteins cyclinB1 and CDK1. Inhibition of miR-92a-3p in combination with si-TOB1 restored cell viability, inhibited cyclin B1 and CDK1 protein levels, and attenuated the G2/M phase block. Taken together, miR-92a-3p reduced the cell proliferation rate of HQ19 and caused cell cycle arrest by targeting TOB1, which in turn contributed to the altered malignant phenotype of the cells. This study suggests that miR-92a-3p is likely to be a biomarker for long-term HQ-induced malignant transformation of TK6 and could be a potential therapeutic target for leukemia caused by long-term exposure to HQ.

GDNF promotes the proliferation and osteogenic differentiation of jaw bone marrow mesenchymal stem cells via the Nr4a1/PI3K/Akt pathway

How to efficiently regenerate jawbone defects caused by trauma, jaw osteomyelitis, tumors, or intrinsic genetic diseases is still challenging. Ectoderm-derived jawbone defect has been reported to be regenerated by selectively recruiting cells from its embryonic origin. Therefore, it is important to explore the strategy for promoting ectoderm-derived jaw bone marrow mesenchymal stem cells (JBMMSCs) on the repair of homoblastic jaw bone. Glial cell-derived neurotrophic factor (GDNF) is an important growth factor and is essential in the process of proliferation, migration and differentiation of nerve cells. However, whether GDNF promoting the function of JBMMSCs and the relative mechanism are not clear. Our results showed that activated astrocytes and GDNF were induced in the hippocampus after mandibular jaw defect. In addition, the expression of GDNF in the bone tissue around the injured area was also significantly increased after injury. Data from in vitro experiments demonstrated that GDNF could effectively promote the proliferation and osteogenic differentiation of JBMMSCs. Furthermore, when implanted in the defected jaw bone, JBMMSCs pretreated with GDNF exhibited enhanced repair effect compared with JBMMSCs without treatment. Mechanical studies found that GDNF induced the expression of Nr4a1 in JBMMSCs, activated PI3K/Akt signaling pathway and then enhanced the proliferation and osteogenic differentiation capacities of JBMMSCs. Our studies reveal that JBMMSCs are good candidates for repairing jawbone injury and pretreated with GDNF is an efficient strategy for enhancing bone regeneration.

Long non-coding RNA LINC01480 is activated by Foxo3a and promotes hydroquinone-induced TK6 cell apoptosis by inhibiting the PI3K/AKT pathway

Long non-coding RNAs (lncRNAs) have been shown to play a critical role in the damage caused to the body by environmental exogenous chemicals; however, few studies have explored their effects during exposure to benzene and its metabolite, hydroquinone (HQ). An emerging lncRNA, LINC01480, was found to be associated with the immune microenvironment of some cancers, but its specific function remains unknown. Therefore, this study aimed to investigate the role of LINC01480 in HQ-induced apoptosis. The biological function of LINC01480 was investigated through gain-of-function and loss-of-function experiments. Mechanically, nuclear-cytoplasmic fractionation experiment, chromatin immunoprecipitation (ChIP), dual-luciferase reporter assay, and rescue experiments were performed. In this study, when TK6 cells were treated with HQ (0, 5, 10, and 20 μM) for 12, 24, 48, and 72 h, the expression of LINC01480 was increased in a dose-dependent manner. Meanwhile, the phosphorylation levels of PI3K and AKT decreased, and apoptosis increased. As compared to the control group, HQ-induced apoptosis was significantly reduced, and the relative survival rate of TK6 cells increased after silencing LINC01480, while overexpression of LINC01480 further sensitized TK6 cells to HQ-induced apoptotic cell death. LINC01480 negatively regulated the PI3K/AKT pathway in TK6 cells, and the apoptosis-inhibiting effect of LINC01480 silencing was reversed after inhibition of the PI3K/AKT pathway. In addition, ChIP and the dual-luciferase reporter assays showed that the transcription factor Foxo3a promoted LINC01480 transcription by directly binding to the promoter regions - 149 to - 138 of LINC01480. Moreover, short-term HQ exposure promoted the expression of Foxo3a. From these findings, we can conclude that LINC01480 is activated by Foxo3a, and promotes HQ-induced apoptosis by inhibiting the PI3K/AKT pathway, suggesting that LINC01480 might become a possible target for therapeutic intervention of HQ-induced toxicity.

Overexpression of YEATS2 Remodels the Extracellular Matrix to Promote Hepatocellular Carcinoma Progression via the PI3K/AKT Pathway

Hepatocellular carcinoma (HCC) is one of the most common cancers and the fourth leading cause of death in men. YEATS domain containing 2 (YEATS2) gene encodes a scaffolding subunit of the ATAC complex. We found that YEATS2 was upregulated in HCC tissues and was associated with a poor prognosis. However, the role of YEATS2 in HCC remains unclear. The purpose of this study was to investigate the effect of YEATS2 on the progression of HCC and to elucidate its related mechanisms. We found that overexpression of YEATS2 promoted tumor cell proliferation, migration, and invasion through the PI3K/AKT signaling pathway and regulation of extracellular matrix. These findings help to understand the role of YEATS2 in HCC, and YEATS2 may become a new target for HCC therapy.

CPT1A modulates PI3K/Akt/mTOR pathway to promote preeclampsia

INTRODUCTION

Preeclampsia (PE) refers to a syndrome of new-onset hypertension with multisystem involvement and damage after 20 weeks of gestation. Defective placentation due to dysregulated behaviors of trophoblast cells is considered a predominant cause of PE.

METHODS

Immunofluorescence (if) and Western blot were used to detect the expression and localization of Carnitine palmitoyltransferase 1A (CPT1A) in placenta. CPT1A protein was overexpressed/knocked down in HTR8/SVneo cells by lentiviral/siRNA interference method. CCK-8 Assay, Western blot, flow cytometry, Wound healing and Transwell assay were used to detect the functional impact of CPT1A on HTR8/SVneo cells. Transcriptomics and bioinformatics analysis were used to predict the possible pathway of CPT1A participating in PE.

RESULTS

CPT1A was upregulated in preeclamptic placentas when compared with normal controls. The abnormal expression of CPT1A in HTR8/SVneo cells is associated with the invasion and migration of HTR8/SVneo cells but is not related to the proliferation, cycle, and apoptosis of HTR8/SVneo cells. The results of Transcriptomic and Western blots suggest that phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway are activated in the si-CPT1A-1796 group. Compared with the si-NC group, the epithelial-mesenchymal transition (EMT) process of HTR8/SVneo cells in the si-CPT1A- 1796 group was significantly enhanced.

DISCUSSION

CPT1A may participate in the pathogenesis of PE by inhibiting the EMT process of HTR8/SVneo cells through the PI3K/AKT/mTOR signaling axis. Thus, the newly unveiled novel function of CPT1A in PE via the PI3K/Akt/mTOR pathway provides a novel insight into the pathogenesis of PE.

Resveratrol attenuates staphylococcal enterotoxin B-activated immune cell metabolism via upregulation of miR-100 and suppression of mTOR signaling pathway

Acute Respiratory Distress Syndrome (ARDS) is triggered by a variety of insults, such as bacterial and viral infections, including SARS-CoV-2, leading to high mortality. In the murine model of ARDS induced by Staphylococcal enterotoxin-B (SEB), our previous studies showed that while SEB triggered 100% mortality, treatment with Resveratrol (RES) completely prevented such mortality by attenuating inflammation in the lungs. In the current study, we investigated the metabolic profile of SEB-activated immune cells in the lungs following treatment with RES. RES-treated mice had higher expression of miR-100 in the lung mononuclear cells (MNCs), which targeted mTOR, leading to its decreased expression. Also, Single-cell RNA-seq (scRNA seq) unveiled the decreased expression of mTOR in a variety of immune cells in the lungs. There was also an increase in glycolytic and mitochondrial respiration in the cells from SEB + VEH group in comparison with SEB + RES group. Together these data suggested that RES alters the metabolic reprogramming of SEB-activated immune cells, through suppression of mTOR activation and its down- and upstream effects on energy metabolism. Also, miR-100 could serve as novel potential therapeutic molecule in the amelioration of ARDS.

Drugging Hijacked Kinase Pathways in Pediatric Oncology: Opportunities and Current Scenario

Childhood cancer is considered rare, corresponding to ~3% of all malignant neoplasms in the human population. The World Health Organization (WHO) reports a universal occurrence of more than 15 cases per 100,000 inhabitants around the globe, and despite improvements in diagnosis, treatment and supportive care, one child dies of cancer every 3 min. Consequently, more efficient, selective and affordable therapeutics are still needed in order to improve outcomes and avoid long-term sequelae. Alterations in kinases' functionality is a trademark of cancer and the concept of exploiting them as drug targets has burgeoned in academia and in the pharmaceutical industry of the 21st century. Consequently, an increasing plethora of inhibitors has emerged. In the present study, the expression patterns of a selected group of kinases (including tyrosine receptors, members of the PI3K/AKT/mTOR and MAPK pathways, coordinators of cell cycle progression, and chromosome segregation) and their correlation with clinical outcomes in pediatric solid tumors were accessed through the R2: Genomics Analysis and Visualization Platform and by a thorough search of published literature. To further illustrate the importance of kinase dysregulation in the pathophysiology of pediatric cancer, we analyzed the vulnerability of different cancer cell lines against their inhibition through the Cancer Dependency Map portal, and performed a search for kinase-targeted compounds with approval and clinical applicability through the CanSAR knowledgebase. Finally, we provide a detailed literature review of a considerable set of small molecules that mitigate kinase activity under experimental testing and clinical trials for the treatment of pediatric tumors, while discuss critical challenges that must be overcome before translation into clinical options, including the absence of compounds designed specifically for childhood tumors which often show differential mutational burdens, intrinsic and acquired resistance, lack of selectivity and adverse effects on a growing organism.

BX795, a kinase inhibitor, inhibit duck plague virus infection via targeting US3 kinase

Duck plague virus (DPV) is a typical DNA virus of waterfowl, it causes huge economic losses to the duck industry due to the higher mortality and lower egg production. The disease is one of the frequent epidemics and outbreaks on duck farms because present vaccines could not provide complete immunity and there are no specific antiviral drugs available. Therefore, the development of antiviral drugs is urgently needed. In this study, we evaluated the antiviral activity of BX795, a specific kinase inhibitor of 3-phosphoinositide-dependent kinase 1 (PDK1), protein kinase B (AKT) and Tank binding kinase 1 (TBK1), against DPV in different duck cells. Our study demonstrated that BX795 reveals prominent antiviral activity in a dose-dependent manner in different types of duck cells. Time-addition and antiviral duration analysis uncovered that BX795 inhibits viral infection therapeutically and its antiviral activity lasts longer than 96 h. Further studies have shown that BX795 prevents cell-to-cell spread of the DPV rather than affects other stage of viral life cycle. Mechanistically, BX795 can inhibit DPV US3 kinase activity, reduce the phosphorylation of US3 substrates, and prevent the interaction between US3 and UL47. Taking together, our study demonstrated BX795, which disrupts the viral kinase activity, is a candidate antiviral agent for DPV.

Investigation of distinct gene expression profile patterns that can improve the classification of intermediate-risk prognosis in AML patients

Background: Acute myeloid leukemia (AML) is a heterogeneous type of blood cancer that generally affects the elderly. AML patients are categorized with favorable-, intermediate-, and adverse-risks based on an individual's genomic features and chromosomal abnormalities. Despite the risk stratification, the progression and outcome of the disease remain highly variable. To facilitate and improve the risk stratification of AML patients, the study focused on gene expression profiling of AML patients within various risk categories. Therefore, the study aims to establish gene signatures that can predict the prognosis of AML patients and find correlations in gene expression profile patterns that are associated with risk groups. Methods: Microarray data were obtained from Gene Expression Omnibus (GSE6891). The patients were stratified into four subgroups based on risk and overall survival. Limma was applied to screen for differentially expressed genes (DEGs) between short survival (SS) and long survival (LS). DEGs strongly related to general survival were discovered using Cox regression and LASSO analysis. To assess the model's accuracy, Kaplan-Meier (K-M) and receiver operating characteristic (ROC) were used. A one-way ANOVA was performed to assess for differences in the mean gene expression profiles of the identified prognostic genes between the risk subcategories and survival. GO and KEGG enrichment analyses were performed on DEGs. Results: A total of 87 DEGs were identified between SS and LS groups. The Cox regression model selected nine genes CD109, CPNE3, DDIT4, INPP4B, LSP1, CPNE8, PLXNC1, SLC40A1, and SPINK2 that are associated with AML survival. K-M illustrated that the high expression of the nine-prognostic genes is associated with poor prognosis in AML. ROC further provided high diagnostic efficacy of the prognostic genes. ANOVA also validated the difference in gene expression profiles of the nine genes between the survival groups, and highlighted four prognostic genes to provide novel insight into risk subcategories poor and intermediate-poor, as well as good and intermediate-good that displayed similar expression patterns. Conclusion: Prognostic genes can provide more accurate risk stratification in AML. CD109, CPNE3, DDIT4, and INPP4B provided novel targets for better intermediate-risk stratification. This could enhance treatment strategies for this group, which constitutes the majority of adult AML patients.

Mechanism of salidroside in the treatment of chronic myeloid leukemia based on the network pharmacology and molecular docking

BACKGROUND

Salidroside is a phenolic natural product, which is a kind of Rhodiola rosea. It has been confirmed that it has inhibitory effects on chronic myeloid leukemia, but the specific performance of its molecular effects is still unclear.

OBJECTIVE

To systematically study the pharmacological mechanism of salidroside on chronic myeloid leukemia by means of network pharmacology.

METHODS

First, the possible target genes of salidroside were predicted through the Traditional Chinese Medicine Pharmacology Database and Analysis Platform, the target gene names were converted into standardized gene names using the Uniprot website. At the same time, the related target genes of chronic myeloid leukemia were collected from GeneCards and DisGenet; Collect summary data and screen for commonly targeted genes. Then, the above-mentioned intersected genes were imported into the String website to construct the protein-protein interaction (PPI) network, and the Gene Ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway were further analyzed. To investigate the overall pharmacological effects of salidroside on chronic myeloid leukemia, we constructed a drug component-target gene-disease (CTD) network. Finally, molecular docking was performed to verify the possible binding conformation between salidroside and the candidate target.

RESULTS

A total of 126 salidroside target genes were retrieved, and 106 of them had interactions with chronic myeloid leukemia. The pharmacological effects of salidroside on chronic myeloid leukemia are related to some important oncogenes and signaling pathways. Molecular docking studies confirmed that the main role of salidroside binding to the target genes is hydrogen bonding.

CONCLUSIONS

We revealed the potential mechanism of action of salidroside against chronic myeloid leukemia, verified by network pharmacology combined with molecular docking. However, salidroside is a promising drug for the prevention and treatment of chronic myeloid leukemia, and further research is needed to prove it.

The PI3K-AKT pathway: A plausible therapeutic target in Parkinson's disease

Parkinson's disease is a common progressive and multifactorial neurodegenerative disease, characterized by the loss of midbrain dopaminergic neurons. Numerous pathological processes including, inflammation, oxidative stress, mitochondrial dysfunction, neurotransmitter imbalance, and apoptosis as well as genetic factors may lead to neuronal degeneration. With the emergence of aging population, the health problem and economic burden caused by PD also increase. Phosphatidylinositol 3-kinases-protein kinase B (PI3K-AKT) signaling pathway regulates signal transduction and biological processes such as cell proliferation, apoptosis and metabolism. According to reports, it regulates neurotoxicity and mediates the survival of neurons. Accumulating evidences indicate that some natural products can play a neuroprotective role by activating PI3K-AKT pathway, providing an effective resource for the discovery of potential therapeutic drugs. The current review provides an overview of the PI3K-AKT signaling pathway and review the relationship between this signaling pathway and PD.

Melatonin Repairs Osteoporotic Bone Defects in Iron-Overloaded Rats through PI3K/AKT/GSK-3β/P70S6k Signaling Pathway

It was found recently that iron overload can cause osteoporosis in rats. Through in vitro and in vivo experimentations, the purpose of the present study was to validate and confirm the inhibitory effects of melatonin on iron death of osteoporosis and its role in bone microstructure improvements. Melatonin (100 mol/L) was administered to MC3T3-E1 cells induced by iron overload in vitro for 48 hours. The expression of cleaved caspase-3 and cleaved PARP and the production of ROS (reactive oxygen species) and mitochondrial damage were all exacerbated by iron overload. On the other hand, melatonin restored these impacts in MC3T3-E1 cells produced by iron overload. By evaluating the expression of PI3K/AKT/GSK-3β/P70S6k signaling pathway-related proteins (RUNX2, BMP2, ALP, and OCN) using RT-PCR and Western blot, osteogenic-related proteins were identified. Alizarin red S and alkaline phosphatase were utilized to evaluate the osteogenic potential of MC3T3-E1 cells. Melatonin significantly improved the osteogenic ability and phosphorylation rates of PI3K, AKT, GSK-3β, and P70S6k in iron overload-induced MC3T3-E1 cells. In vivo, melatonin treated iron overload-induced osteoporotic bone defect in rats. Rat skeletal microstructure was observed using micro-CT and bone tissue pathological section staining. ELISA was utilized to identify OCN, PINP, CTX-I, and SI in the serum of rats. We discovered that melatonin increased bone trabecular regeneration and repair in osteoporotic bone defects caused by iron overload. In conclusion, melatonin enhanced the osteogenic ability of iron overload-induced MC3T3-E1 cells by activating the PI3K/AKT/GSK-3β/P70S6k signaling pathway and promoting the healing of iron overload-induced osteoporotic bone defects in rats.

LncRNA MEG3 attenuates the malignancy of retinoblastoma cells through inactivating PI3K /Akt/mTOR signaling pathway

Retinoblastoma (RB) is the most common neoplasm found in the eye of children. There are increasing interests to develop targeted gene therapy for this disease. This study was performed to investigate the impact of long non-coding RNA (lncRNA) MEG3 on the biological features of RB cells. Vector overexpressing MEG3 was constructed and introduced into two RB cell lines. Transfected RB cells were assessed for proliferation, apoptosis, migration ability, expression levels of important genes in the PI3K/Akt/mTOR signaling pathway using qRT-PCR and Western blot analysis. Xenograft mouse models were constructed to determine the tumorigenicity of RB cells overexpressing MEG3. MEG3 mRNA level was significantly lower in RB cells than in non-cancer cells (p < 0.01). Overexpressing MEG3 resulted in significant reduction in cell proliferation (p < 0.05), migration (p < 0.01) and significant increase in apoptosis (p < 0.01). After overexpressing MEG3, p-PI3K, p-Akt and p-mTOR levels were significantly downregulated (p < 0.01). Furthermore, in the xenograft model, RB cells overexpressing MEG3 generated significantly smaller tumors as compared to RB cells that did not overexpress MEG3 (p < 0.05). Our data suggest that MEG3 increases apoptosis and reduces tumorigenicity of RB cells through inactivating the PI3K/Akt/mTOR pathway. Therefore, MEG3 could be further investigated as a potential new therapeutic agent and target for RB therapy.

Glucose Metabolism in Acute Myeloid Leukemia Cell Line Is Regulated via Combinational PI3K/AKT/mTOR Pathway Inhibitors

Background

Metabolism reprogramming is a survival mechanism in acute myeloid leukemia (AML) cells in the tumor microenvironment. Therefore, we investigated the effect of signaling pathway inhibitors on the expression of genes rewired in the metabolic pathway of AML cells.

Methods

HL-60 cells were treated with Idelalisib, MK-2206, and Everolimus, which respectively are selective inhibitors of phosphatidylinositol-3-kinase (PI3K), AKT, and the mammalian target of rapamycin (mTOR), either individually or in combination. The relative expressions of glucose transporter 1, hexokinase 2, pyruvate kinase, pyruvate dehydrogenase E1, citrate synthase, isocitrate dehydrogenase 2, and hypoxia inducible factor 1 subunit alpha were determined by real-time PCR.

Results

The combined treatment of HL-60 cells with Idelalisib, MK-2206, and Everolimus decreased the expression of glucose transporter 1, hexokinase 2, pyruvate kinase M2, pyruvate dehydrogenase E1, citrate synthase, isocitrate dehydrogenase 2, and hypoxia inducible factor 1 subunit alpha.

Conclusions

A combination of PI3K/AKT/mTOR pathway inhibitors regulates the expression of genes involved in glycolysis, pyruvate dehydrogenase complex (PDH), and the tricarboxylic acid (TCA) cycle and interferes with metabolic reprogramming and immune evasion mechanisms of AML leukemic cells. Combinational therapy approaches to block these pathways might be a promising and novel therapeutic strategy for targeting the metabolic requirements of AML cells.

Targeting integrated stress response with ISRIB combined with imatinib treatment attenuates RAS/RAF/MAPK and STAT5 signaling and eradicates chronic myeloid leukemia cells

The integrated stress response (ISR) facilitates cellular adaptation to unfavorable conditions by reprogramming the cellular response. ISR activation was reported in neurological disorders and solid tumors; however, the function of ISR and its role as a possible therapeutic target in hematological malignancies still remain largely unexplored. Previously, we showed that the ISR is activated in chronic myeloid leukemia (CML) cells and correlates with blastic transformation and tyrosine kinase inhibitor (TKI) resistance. Moreover, the ISR was additionally activated in response to imatinib as a type of protective internal signaling. Here, we show that ISR inhibition combined with imatinib treatment sensitized and more effectively eradicated leukemic cells both in vitro and in vivo compared to treatment with single agents. The combined treatment specifically inhibited the STAT5 and RAS/RAF/MEK/ERK pathways, which are recognized as drivers of resistance. Mechanistically, this drug combination attenuated both interacting signaling networks, leading to BCR-ABL1- and ISR-dependent STAT5 activation. Consequently, leukemia engraftment in patient-derived xenograft mice bearing CD34+ TKI-resistant CML blasts carrying PTPN11 mutation responsible for hyperactivation of the RAS/RAF/MAPK and JAK/STAT5 pathways was decreased upon double treatment. This correlated with the downregulation of genes related to the RAS/RAF/MAPK, JAK/STAT5 and stress response pathways and was associated with lower expression of STAT5-target genes regulating proliferation, viability and the stress response. Collectively, these findings highlight the effect of imatinib plus ISRIB in the eradication of leukemic cells resistant to TKIs and suggest potential clinical benefits for leukemia patients with TKI resistance related to RAS/RAF/MAPK or STAT5 signaling. We propose that personalized treatment based on the genetic selection of patients carrying mutations that cause overactivation of the targeted pathways and therefore make their sensitivity to such treatment probable should be considered as a possible future direction in leukemia treatment.

Strategies to enhance CAR-T persistence

Chimeric antigen receptor T (CAR-T) cell therapy has significantly improved the life expectancy for patients with refractory or relapse B cell lymphoma. As for B cell acute lymphoblastic leukemia (B-ALL), although the primary response rate is promising, the high incidence of early relapse has caused modest long-term survival with CAR-T cell alone. One of the main challenges is the limited persistence of CAR-T cells. To further optimize the clinical effects of CAR-T cells, many studies have focused on modifying the CAR structure and regulating CAR-T cell differentiation. In this review, we focus on CAR-T cell persistence and summarize the latest progress and strategies adopted during the in vitro culture stage to optimize CAR-T immunotherapy by improving long-term persistence. Such strategies include choosing a suitable cell source, improving culture conditions, combining CAR-T cells with conventional drugs, and applying genetic manipulations, all of which may improve the survival of patients with hematologic malignancies by reducing the probability of recurrence after CAR-T cell infusion and provide clues for solid tumor CAR-T cell therapy development.

Deep learning-based transcriptome model predicts survival of T-cell acute lymphoblastic leukemia

Identifying subgroups of T-cell acute lymphoblastic leukemia (T-ALL) with poor survival will significantly influence patient treatment options and improve patient survival expectations. Current efforts to predict T-ALL survival expectations in multiple patient cohorts are lacking. A deep learning (DL)-based model was developed to determine the prognostic staging of T-ALL patients. We used transcriptome sequencing data from TARGET to build a DL-based survival model using 265 T-ALL patients. We found that patients could be divided into two subgroups (K0 and K1) with significant difference (P&lt; 0.0001) in survival rate. The more malignant subgroup was significantly associated with some tumor-related signaling pathways, such as PI3K-Akt, cGMP-PKG and TGF-beta signaling pathway. DL-based model showed good performance in a cohort of patients from our clinical center (P = 0.0248). T-ALL patients survival was successfully predicted using a DL-based model, and we hope to apply it to clinical practice in the future.

Convallatoxin Inhibits Cell Proliferation and Induces Cell Apoptosis by Attenuating the Akt-E2F1 Signaling Pathway in K562 Cells

Objective: To determine the effect of convallatoxin on K562 cell proliferation and apoptosis. Methods: CCK-8 assay was used to detect cell proliferation; PI staining, JC-1 staining, and Annexin V-FITC/PI double staining were used to analyze the cell cycle, cell mitochondrial membrane potential, and cell apoptosis; and Western blotting was used to detect cleaved caspase-9, cleaved caspase-3, Bcl-2, Bax, and E2F1 expression and Akt phosphorylation. Subsequently, AutoDock software was used to determine the interaction between convallatoxin and Akt1. Results: Upon treatment with convallatoxin, the proliferation of K562 cells was inhibited, the cells were arrested at the S and G2/M phases, and cell apoptosis was significantly induced. In addition, Akt phosphorylation and E2F1 expression were significantly decreased, whereas E2F1 overexpression rescued convallatoxin-induced cell proliferation and apoptosis. In addition, a molecular docking assay indicated that convallatoxin could bind to Akt1. Conclusion: Convallatoxin inhibited cell proliferation and induced mitochondrial-related apoptosis in K562 cells by reducing the Akt-E2F1 signaling pathway, indicating that it is a potential agent for treating leukemia.

USF2-mediated upregulation of TXNRD1 contributes to hepatocellular carcinoma progression by activating Akt/mTOR signaling

Thioredoxin reductase 1 (TXNRD1) is one of the major redox regulators in mammalian cells, which has been reported to be involved in tumorigenesis. However, its roles and regulatory mechanism underlying the progression of HCC remains poorly understood. In this study, we demonstrated that TXNRD1 was significantly upregulated in HCC tumor tissues and correlated with poor survival in HCC patients. Functional studies indicated TXNRD1 knockdown substantially suppressed HCC cell proliferation and metastasis both in vitro and in vivo, and its overexpression showed opposite effects. Mechanistically, TXNRD1 attenuated the interaction between Trx1 and PTEN which resulting in acceleration of PTEN degradation, thereby activated Akt/mTOR signaling and its target genes which conferred to elevated HCC cell mobility and metastasis. Moreover, USF2 was identified as a transcriptional suppressor of TXNRD1, which directly interacted with two E-box sites in TXNRD1 promoter. USF2 functioned as tumor suppressor through the downstream repression of TXNRD1. Further clinical data revealed negative co-expression correlations between USF2 and TXNRD1. In conclusion, our findings reveal that USF2-mediated upregulation of TXNRD1 contributes to hepatocellular carcinoma progression by activating Akt/mTOR signaling.

Proanthocyanidins inhibit the apoptosis and aging of nucleus pulposus cells through the PI3K/Akt pathway delaying intervertebral disc degeneration

BACKGROUND

Low back pain is a common symptom of intervertebral disc degeneration (IDD), which seriously affects the quality of life of patients. The abnormal apoptosis and senescence of nucleus pulposus (NP) cells play important roles in the pathogenesis of IDD. Proanthocyanidins (PACs) are polyphenolic compounds with anti-apoptosis and anti-aging effects. However, their functions in NP cells are not yet clear. Therefore, this study was performed to explore the effects of PACs on NP cell apoptosis and aging and the underlying mechanisms of action.

METHODS

Cell viability was evaluated by cell counting kit-8 (CCK-8) assay. The apoptosis rate was determined TUNEL assays. Levels of apoptosis-associated molecules (Bcl-2, Bax, C-caspase-3 and Caspase-9) were evaluated via western blot. The senescence was observed through SA-β-gal staining and western blotting analysis was performed to observe the expression of senescence-related molecules (p-P53, P53, P21 and P16).

RESULTS

Pretreatment with PACs exhibited protective effects against IL-1β-induced NP cell apoptosis including apoptosis rate, expressions of proapoptosis and antiapoptosis related genes and protein. PACs could also alleviate the increase of p-p53, P21, and P16 in IL-1β-treated NP cells. SA-β-gal staining showed that IL-1β-induced senescence of NP cells was prevented by PACs pertreatment. In addition, PACs activated PI3K/Akt pathway in IL-1β-stimulated NP cells. However, these protected effects were inhibited after LY294002 treatment.

CONCLUSION

The results of the present study showed that PACs inhibit IL-1β-induced apoptosis and aging of NP cells by activating the PI3K/Akt pathway, and suggested that PACs have therapeutic potential for IDD.

Targeting PI3K/AKT/mTOR Signaling Pathway in Pancreatic Cancer: From Molecular to Clinical Aspects

Although pancreatic cancer (PC) was considered in the past an orphan cancer type due to its low incidence, it may become in the future one of the leading causes of cancer death. Pancreatic ductal adenocarcinoma (PDAC) is the most frequent type of PC, being a highly aggressive malignancy and having a 5-year survival rate of less than 10%. Non-modifiable (family history, age, genetic susceptibility) and modifiable (smoking, alcohol, acute and chronic pancreatitis, diabetes mellitus, intestinal microbiota) risk factors are involved in PC pathogenesis. Chronic inflammation induced by various factors plays crucial roles in PC development from initiation to metastasis. In multiple malignant conditions such as PC, cytokines, chemokines, and growth factors activate the class I phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) (PI3K/AKT/mTOR) signaling pathway, which plays key roles in cell growth, survival, proliferation, metabolism, and motility. Currently, mTOR, AKT, and PI3K inhibitors are used in clinical studies. Moreover, PI3K/mTOR dual inhibitors are being tested in vitro and in vivo with promising results for PC patients. The main aim of this review is to present PC incidence, risk factors, tumor microenvironment development, and PI3K/AKT/mTOR dysregulation and inhibitors used in clinical, in vivo, and in vitro studies.

Overexpression of circ PTK2 suppresses the progression of nonalcoholic fatty liver disease via the miR-200c/SIK2/PI3K/Akt axis

Excessive hepatic lipid accumulation is involved in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). A previous study showed that the circular RNA (circRNA) PTK2 was significantly downregulated in NAFLD mice. However, the detailed function of circ PTK2 in NAFLD remains unclear. A high-fat diet (HFD) was used to establish a mouse model of NAFLD, and free fatty acid (FFA) treatment was used to establish an in vitro model of NAFLD. Oil red O staining was used to evaluate lipid accumulation. The pathological changes in mice were observed by HE staining. Western blotting and RT-qPCR were applied to assess protein and mRNA levels, respectively. A dual luciferase reporter assay and RIP were used to explore the relationship among circ PTK2, miR-200c and SIK2. Circ PTK2 and SIK2 were downregulated and miR-200c was upregulated in NAFLD. Upregulation of circ PTK2 reversed lipid accumulation in FFA-treated HepG2 cells. Moreover, circ PTK2 bound to miR-200c, and SIK2 was identified as the direct target of miR-200c. Moreover, the miR-200c inhibitor-induced decrease in lipid accumulation was reversed by SIK2 knockdown. Furthermore, the impact of circ PTK2 overexpression on PI3K/Akt signaling was partially reversed by SIK2 silencing. Circ PTK2 overexpression alleviates NAFLD development via the miR-200c/SIK2/PI3K/Akt axis. Thus, our work might provide new methods for NAFLD treatment.

Leonurus japonicus Houttuyn induces reactive oxygen species-mediated apoptosis via regulation of miR-19a-3p/PTEN/PI3K/AKT in U937 and THP-1 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Leonurus japonicus Houttuyn is a medicinal ingredient in more than 300 prescriptions in traditional Korean medicine. It is especially important for women's health and blood-related diseases. Recent research revealed that Leonurus japonicus Houttuyn extracts have antioxidative, anticancer, analgesic, anti-inflammatory, and neuroprotective properties.

AIM OF THE STUDY

However, its underlying anti-cancerous mechanisms remain unclear. This study elucidated the anticancer mechanism of Leonurus japonicus Houttuyn in U937 and THP-1 cancer cells.

MATERIALS AND METHODS

High-performance liquid chromatography (HPLC) was used for detecting main compound of Leonurus japonicus Houttuyn, rutin. EZ-Cytox cell viability assay, Western blot analysis, live and dead cell assay, 2', 7' dichlorofluorescin diacetate (DCFDA) assay, quantitative real-time PCR (qRT-PCR) analysis, and microRNA (miR) mimic transfection assay were applied to further investigate anti-cancer efficacies and underlying mechanism in U937 and THP-1 cells.

RESULTS

The main compound of Leonurus japonicus Houttuyn, rutin was detected using HPLC. The cytotoxic effect of Leonurus japonicus Houttuyn was exerted in U937 and THP-1 cancer cells but not in MDBK and IEC-6 normal cells. Leonurus japonicus Houttuyn decreased mitochondria membrane potential (ΔΨm). Consistently, Leonurus japonicus Houttuyn reduced the expression of survivin and cleaved caspase-9, caspase-3, and poly (ADP-ribose) polymerase (PARP). Cell death was increased in Leonurus japonicus Houttuyn treated groups. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and CCAAT-enhancer-binding protein homologous protein (CHOP) was increased and phosphatidylinositol-3-kinase (PI3K) and Protein kinase B (AKT) were decreased by Leonurus japonicus Houttuyn. Reactive oxygen speices generation was elevated by Leonurus japonicus Houttuyn and its cytotoxicity was reversed by N-acetyl-l-cysteine (NAC) pretreatment. Moreover, onco-microRNA (miR), miR-19a-3p was suppressed by Leonurus japonicus Houttuyn and transfection of miR-19a-3p mimic reversed the regulated PTEN, p-AKT, CHOP expression, attenuating Leonurus japonicus Houttuyn induced apoptosis.

CONCLUSIONS

These findings indicated that Leonurus japonicus Houttuyn has anti-cancer effects by regulation of PTEN/PI3K/AKT signal pathway and ROS-related ER stress-induced apoptosis via regulation of miR-19a-3p. Leonurus japonicus Houttuyn may be an effective candidate for triggering PTEN-dependent apoptosis of cancer cells related to acute myeloid leukemia.

Targeting metabolism: A potential strategy for hematological cancer therapy

Most hematological cancer-related relapses and deaths are caused by metastasis; thus, the importance of this process as a target of therapy should be considered. Hematological cancer is a type of cancer in which metabolism plays an essential role in progression. Therefore, we are required to block fundamental metastatic processes and develop specific preclinical and clinical strategies against those biomarkers involved in the metabolic regulation of hematological cancer cells, which do not rely on primary tumor responses. To understand progress in this field, we provide a summary of recent developments in the understanding of metabolism in hematological cancer and a general understanding of biomarkers currently used and under investigation for clinical and preclinical applications involving drug development. The signaling pathways involved in cancer cell metabolism are highlighted and shed light on how we could identify novel biomarkers involved in cancer development and treatment. This review provides new insights into biomolecular carriers that could be targeted as anticancer biomarkers.

The role of miRNAs as a big master regulator of signaling pathways involved in lymphoblastic leukemia

MicroRNAs (miRNAs) belong to small noncoding RNAs, which have long attracted researchers' attention because of their potency in acting either as oncogenes or tumor-suppressors in cancers. acute lymphocytic leukemia (ALL) and chronic lymphocytic leukemia (CLL) are two known types of leukemia with high mortality rates in adults and children. On a molecular basis, various signaling pathways are active in both types, making researchers consider the potential role of miRNAs in activating or suppressing these pathways to further hinder cancer development. In this review, we summarized the potential miRNAs, especially circulating ones, involved in essential signaling pathways in the ALL and CLL patients which serve as biomarkers and valuable targets in the treatment fields.

Novel Compound, ND-17, Regulates the JAK/STAT, PI3K/AKT, and MAPK Pathways and Restrains Human T-Lymphoid Leukemia Development

Background:

T cell acute lymphoblastic leukemia (T-ALL) is an invasive hematological malignant disorder of T cell progenitors. The Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway plays an important role in the development of T-ALL and in the inhibition of the key molecule, JAK2, and could suppress T-ALL cell proliferation.

Objective:

The objective of this study was to investigate the in vitro anti-tumor effects of a novel nilotinib derivative, ND-17, on cancer cell lines via its interactions with JAK2.

Methods:

The effects of ND-17 on cell proliferation and on cell cycle and apoptosis were evaluated using the tetrazolium assay and flow cytometry, respectively. In addition, the ND-17/JAK2 binding interactions were evaluated using surface plasmon resonance and western blot analyses.

Results:

ND-17 exerted the greatest inhibitory effects on T-ALL cells amongst all hematological cancer cell lines tested. Flow cytometric analysis indicated that ND-17 blocked the cell cycle at the S phase in T-ALL cells. Nilotinib did not significantly inhibit T-ALL cell growth or regulate cell cycle. Preliminary investigations revealed that the regulation of cyclin-dependent kinases/cyclins was attributed to ND-17-induced cell cycle arrest. Furthermore, ND-17 could bind to JAK2 with strong affinity and more importantly, ND-17 bound to the ATP pocket of JAK2 in a manner similar to the potent inhibitor. Thus, ND-17 treatment exhibited a prominent effect in inhibiting the phosphorylation of JAK2 in T-ALL cells. An increase in the phosphorylation of JAK2 was observed in interleukin-6-stimulated Jurkat cells, which was reversed by ND-17 treatment. Meanwhile, the combination of TG-101348 and ND-17 led to further improvement in inhibiting phosphorylation of JAK2. Moreover, the transfection and knockdown of JAK2 altered the inhibitory effect of ND-17 on Jurkat cell viability. In addition, ND-17 treatment suppressed the JAK/STAT, phosphatidylinositol-3-kinase/protein kinase B/mechanistic target of rapamycin, and mitogen-activated protein kinase/extracellular signal-regulated protein kinases 1 and 2 signaling pathways.

Conclusion:

These findings suggest that ND-17 could be a promising JAK2 inhibitor for the treatment of T-ALL.

[Naphthalene allyl trifluoromethyl benzocyclopentanone inhibits proliferation and induces apoptosis of lung cancer A549 cells in vitro]

OBJECTIVE

To investigate the molecular mechanism by which a novel naphthalene allyl trifluoromethyl benzocyclopentanone XX0335 inhibits the proliferation and induces apoptosis of lung cancer A549 cells.

METHODS

Lung cancer A549 cells were treated with 0.1% DMSO (control) or different concentrations (6.25, 12.5, and 25 μg/mL) of XX0335, and the changes in cell viability, cell cycle, proliferation and apoptosis were assessed with CCK-8 assay, EdU experiment, and flow cytometry. The effects of different concentrations of XX0335 on phosphorylation levels of proliferation-related proteins Akt, mTOR, Akt/mTOR and the expressions of cleaved PARP and cyclin D1 were determined using Western blotting. We also assessed the effect of XX0335 on tumor growth in a mouse model bearing A945 cell xenograft.

RESULTS

Treatment with XX0335 reduced the viability of A549 cells in a dose-dependent manner (P < 0.01) and significantly inhibited cell proliferation (P < 0.001). Flow cytometry showed that XX0335 treatment promoted apoptosis of the cells (P < 0.01) and caused an obvious increase of the number of G1-phase cells. Compared with DMSO, XX0335 significantly inhibited the phosphorylation of Akt and mTOR, increased the expression of cleaved PARP, and lowered the protein expression of cyclin D1. In the tumor-bearing mouse models, injection of XX0335 significantly decreased the tumor volume (P < 0.01).

CONCLUSION

XX0335 inhibits the proliferation, cycle and induces apoptosis of lung cancer A549 cells possibly by inhibiting the Akt/mTOR signal pathway.