Vav1 is necessary for PU.1 mediated upmodulation of miR-29b in acute myeloid leukaemia-derived cells

Ginsenoside Rd Induces Differentiation of Myeloid Leukemia Cells via Regulating ERK/GSK-3β Signaling Pathway

OBJECTIVE

To investigate the role of ginsenoside Rd (GRd) in acute myeloid leukemia (AML) cell differentiation.

METHODS

AML cells were treated with GRd (25, 50, 100 and 200 µg/mL), retinoic acid (RA, 0.1g/L) and PD98059 (20 mg/mL) for 72 h, cell survival was detected by methylthiazolyldiphenyl-tetrazolium bromide and colony formation assays, and cell cycle was detected by flow cytometry. Cell morphology and differentiation were observed by Wright-Giemsa staining, peroxidase chemical staining and cellular immunochemistry assay, respectively. The protein expression levels of GATA binding protein 1 (GATA-1), purine rich Box-1 (PU.1), phosphorylated-extracellular signal-related kinase (p-ERK), ERK, phosphorylated-glycogen synthase kinase-3β (p-GSK3β), GSK3β and signal transducer and activator of transcription 1 (STAT1) were detected by Western blot. Thirty-six mice were randomly divided into 3 groups using a random number table: model control group (non-treated), GRd group [treated with 200 mg/(kg·d) GRd] and homoharringtonine (HTT) group [treated with 1 mg/(kg·d) HTT]. A tumor-bearing nude mouse model was established, and tumor weight and volume were recorded. Changes of subcutaneous tumor tissue were observed after hematoxylin and eosin staining. WT1 and GATA-1 expressions were detected by immunohistochemical staining.

RESULTS

The cell survival was inhibited by GRd in a dose-dependent manner and GRd caused G0/G1 cell arrest (p<0.05). GRd treatment induced leukemia cell differentiation, showing increased expressions of peroxidase and specific proteins concerning erythrogenic or granulocytic differentiation (p<0.05). GRd treatment elicited upregulation of p-ERK, p-GSK-3β and STAT1 expressions in cells, and reversed the effects of PD98059 on inhibiting the expressions of peroxidase, GATA-1 and PU.1 (P<0.05). After GRd treatment, tumor weight and volume of mice were decreased, and tumor cells underwent massive apoptosis and necrosis (P<0.05). WT1 level was decreased, and GATA-1 level was significantly increased in subcutaneous tumor tissues (P<0.05 or P<0.01).

CONCLUSION

GRd might induce the differentiation of AML cells via regulating the ERK/GSK-3β signaling pathway.

Bone Marrow Mesenchymal Stem Cell-Derived miR-29b Promotes the Progression of Acute Myeloid Leukemia

This study investigates the effect of low miR-29b expression derived from bone marrow mesenchymal stem cells (BMSC) on AML. miR-29b expression in acute leukemia drug resistant cell line as K562/ADM was detected with RT-PCR. Cell proliferation was tested with MTT assay and apoptosis was analyzed by flow cytometry. The correlation between miR-29b and PDGFRα level was analyzed. miR-29b expression was reduced after si-miR-29b transfection. PDGFRα expression was increased by the low miR-29b expression in AML cells so as to prompt the progression of AML. Cell proliferation in K562/ADM was increased after miR-29b expression was reduced and quantity of apoptosis was decreased. There was a correlation of miR-29b and PDGFRα in the staging of AML (P <0.05). In conclusion, AML could be aggravated by the low miR-29b expression possibly through regulating PDGFRα, resulting in increased drug tolerance.

Mir-29b in Breast Cancer: A Promising Target for Therapeutic Approaches

The miR-29 family comprises miR-29a, miR-29b, and miR-29c, and these molecules play crucial and partially overlapped functions in solid tumors, in which the different isoforms are variously de-regulated and mainly correlated with tumor suppression. miR-29b is the most expressed family member in cancer, in which it is involved in regulating gene expression at both transcriptional and post-transcriptional levels. This review focuses on the role of miR-29b in breast cancer, in which it plays a controversial role as tumor suppressor or onco-miRNA. Here we have highlighted the dual effect of miR-29b on breast tumor features, which depend on the prevailing function of this miRNA, on the mature miR-29b evaluated, and on the breast tumor characteristics. Remarkably, the analyzed miR-29b form emerged as a crucial element in the results obtained by various research groups, as the most abundant miR-29b-3p and the less expressed miR-29b1-5p seem to play distinct roles in breast tumors with different phenotypes. Of particular interest are the data showing that miR-29b1-5p counteracts cell proliferation and migration and reduces stemness in breast tumor cells with a triple negative phenotype. Even if further studies are required to define exactly the role of each miR-29b, our review highlights its possible implication in phenotype-specific management of breast tumors.

miR-29b-3p suppresses the malignant biological behaviors of AML cells via inhibiting NF-κB and JAK/STAT signaling pathways by targeting HuR

Background

HuR/ELAVL1 (embryonic lethal abnormal vision 1) was a downstream target of miR-29b in some cancer cells. HuR protein exerts important prognostic effects of involving in the pathogenesis and development of acute myeloid leukemia (AML). This study aims to investigate the role of miR-29b-3p in biological behaviors of AML cells by targeting HuR and the involvement of the NF-κB and JAK/STAT signaling pathways.

Methods

The expressions of HuR and miR-29b-3p in AML cells were determined using RT-qPCR and Western blot, and the association between them was analyzed using the Spearman method. Next, the target relationship between HuR and miR-29b-3p was predicted by biological information databases and verified by the dual-luciferase reporter gene assay. MTS, methyl cellulose, flow cytometry and transwell assay were employed to detect the cell proliferation, clone formation, cell cycle and apoptosis, invasion and migration respectively, the effect of miR-29b-3p targeted HuR on the biological behaviors of AML cells was explored after over- /down-expression of miR-29b-3p and rescue experiment. Then, immunofluorescence assay and western blot were employed to detect location expression and phosphorylation levels of NF-κB and JAK/STAT signaling pathways related molecules respectively.

Results

HuR was negatively correlated with miR-29b-3p, and was the downstream target of miR-29b-3p in AML cells. When miR-29b-3p was overexpressed in AML cells, HuR was down-regulated, accompanied by cell viability decreased, cell cycle arrest, apoptosis increased, invasion and migration weakened. Moreover, the opposite result appeared after miR-29b-3p was down-regulated. The rescue experiment showed that miR-29b-3p inhibitor could reverse the biological effect of HuR down-regulation in AML cells. Molecular pathway results showed that miR-29b-3p could inhibit p65 expression in nucleus and phosphorylation levels of p65, IκBα, STAT1, STAT3 and STAT5.

Conclusion

miR-29b-3p can inhibit malignant biological behaviors of AML cells via the inactivation of the NF-κB and JAK/STAT signaling pathways by targeting HuR. miR-29b-3p and its target HuR can be used as a new potential molecular for AML treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09996-1.

Vav1 Selectively Down-Regulates Akt2 through miR-29b in Certain Breast Tumors with Triple Negative Phenotype

Triple negative breast cancer (TNBC) represents the most aggressive breast tumor, showing a high intrinsic variability in terms of both histopathological features and response to therapies. Blocking the Akt signaling pathway is a well-studied approach in the treatment of aggressive breast tumors. The high homology among the Akt isoforms and their distinct, and possibly opposite, oncogenic functions made it difficult to develop effective drugs. Here we investigated the role of Vav1 as a potential down-regulator of individual Akt isozymes. We revealed that the over-expression of Vav1 in triple negative MDA-MB-231 cells reduced only the Akt2 isoform, acting at the post-transcriptional level through the up-modulation of miR-29b. The Vav1/miR-29b dependent decrease in Akt2 was correlated with a reduced lung colonization of circulating MDA-MB-231 cells. In cell lines established from PDX, the Vav1 induced down-modulation of Akt2 is strongly dependent on miR-29b and occurs only in some TNBC tumors. These findings may contribute to better classify breast tumors having the triple negative phenotype, and suggest that the activation of the Vav1/miR-29b axis, precisely regulating the amount of an Akt isozyme crucial for tumor dissemination, could have great potential for driving more accurate therapies to TNBCs, often not eligible or resistant to treatments.

Clinical Value of Serum miRNA in Patients with Acute Promyelocytic Leukemia

Objective

To explore the clinical value of specific miRNA in patients with acute promyelocytic leukemia.

Methods

129 patients with acute promyelocytic leukemia diagnosed in our hospital from January 2015 to January 2020 were selected as the observation group. At the same time, 74 patients with nonacute promyelocytic leukemia who underwent bone marrow aspiration were included as the control group. The expression levels of miR-126-5p and miR-13, different characteristic parameters, and prognosis were compared between the two groups, and the clinical significance of miR-126-5p and miR-13 in acute promyelocytic leukemia was analyzed.

Results

The expression of miR-126-5p (12.31 ± 2.25 versus 17.30 ± 3.28) and miR-13 (16.05 ± 3.47 versus 21.66 ± 2.18) in the observation group was significantly lower than that in the control group (P < 0.05). The expression level of miR-126-5p was significantly correlated with lactate dehydrogenase level, HGB level, NPM1 mutant type, and complete remission (P < 0.05). The expression level of miR-13 was significantly correlated with HGB level, NPM1 mutant type, and complete remission (P < 0.05). Both expression levels of miR-126-5p and miR-13 were not correlated with sex, age, WBC, PLT, proportion of bone marrow primordial cells, hepatomegaly, splenomegaly, lymph node enlargement, and FLT3-ITD (P > 0.05). Cox multivariate regression analysis showed that peripheral blood WBC, bone marrow blast cell count, and miR-126-5p and miR-13 were prognostic factors in patients with acute promyelocytic leukemia (P < 0.05). The sensitivity, specificity, accuracy, and AUC of serum miR-126-5p prediction were 75.83%, 84.56%, 82.17%, and 0.729, respectively. The sensitivity, specificity, accuracy, and AUC of serum miR-13 prediction were 78.64%, 88.49%, 86.20% and 0.882, respectively.

Conclusion

Serum miR-126-5p and miR-13 are closely related to the prognosis of patients with acute promyelocytic leukemia. Serum miR-126-5p and miR-13 can be used as reliable indexes to predict the prognosis of patients.

Pulsed Electromagnetic Fields Modulate miRNAs During Osteogenic Differentiation of Bone Mesenchymal Stem Cells: a Possible Role in the Osteogenic-angiogenic Coupling

Despite the high intrinsic ability of bone tissue to regenerate, bone healing fails in some pathological conditions and especially in the presence of large defects. Due to the strong relationship between bone development and vascularization during in vivo bone formation and repair, strategies promoting the osteogenic-angiogenic coupling are crucial for regenerative medicine. Increasing evidence shows that miRNAs play important roles in controlling osteogenesis and bone vascularization and are important tool in medical research although their clinical use still needs to optimize miRNA stability and delivery. Pulsed electromagnetic fields (PEMFs) have been successfully used to enhance bone repair and their clinical activity has been associated to their ability to promote the osteogenic differentiation of human mesenchymal stem cells (hMSCs). In this study we investigated the potential ability of PEMF exposure to modulate selected miRNAs involved in the osteogenic differentiation of human bone mesenchymal stem cells (hBMSCs). We show that, during in vitro hBMSC differentiation, PEMFs up-modulate the expression of miR-26a and miR-29b, which favor osteogenic differentiation, and decrease miR-125b which acts as an inhibitor miRNA. As PEMFs promote the expression and release of miRNAs also involved in angiogenesis, we conclude that PEMFs may represent a noninvasive and safe strategy to modulate miRNAs with relevant roles in bone repair and with the potential to regulate the osteogenic-angiogenic coupling.

Vav1 Sustains the In Vitro Differentiation of Normal and Tumor Precursors to Insulin Producing Cells Induced by all-Trans Retinoic Acid (ATRA)

All-trans retinoic acid (ATRA) promotes the development and the function of insulin producing cells and induces partial differentiation of pancreatic tumor cells. A number of evidences clearly indicate that the ATRA mediated signaling may have a substantial role in therapeutic approaches based on restoration of functional β-cells. Among the proteins up-regulated by ATRA, Vav1 is involved in maturation and function of haematopoietic cells and is essential for retinoids induced differentiation of tumor promyelocytes. The presence of Vav1 in solid tissues, including pancreas, is considered ectopic and no role in the differentiation of human epithelial cells has so far been described. We demonstrated here that Vav1 sustains the maturation to β-cells of the normal precursors human Biliary Tree Stem/progenitor Cells (hBTSCs) induced by a differentiation medium containing ATRA and that, in the mature normal pancreas, insulin-producing cells express variable levels of Vav1. Using pancreatic ductal adenocarcinoma (PDAC)-derived cells, we also revealed that the ATRA induced up-modulation of Vav1 is essential for the retinoid-induced trans-differentiation of neoplastic cells into insulin producing cells. The results of this study identify Vav1 as crucial molecule in ATRA induced maturation of insulin producing cells and suggest this protein as a marker for new strategies ended to restore functional β-cells.

Vav1 Down-Modulates Akt2 Expression in Cells from Pancreatic Ductal Adenocarcinoma: Nuclear Vav1 as a Potential Regulator of Akt Related Malignancy in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is the most aggressive tumor malignancy worldwide, mainly due to uncontrolled metastasis. Among the numerous molecules deregulated in PDAC, different members of the Akt pathways are of great importance because they are involved in tumor cell proliferation, migration, and invasion. We have recently demonstrated that Vav1, ectopically expressed in solid tumors, is capable of down-modulating expression and/or activation of specific Akt isoforms in breast cancer cells. By using pancreatic cell lines expressing different basal levels of Vav1, we demonstrated here that Vav1 down-regulates the expression of Akt2, known to correlate with tumor metastases and resistance to therapy. In particular, while the silencing of Vav1 is sufficient to induce Akt2, its up-modulation reduces Akt2 levels only when Vav1 accumulates inside the nucleus of PDAC cells. Moreover, in PDAC tissues, we revealed that high nuclear levels of Vav1 correlate with low Akt2 expression. Although we cannot demonstrate the mechanisms involved, our results provide new insights into the role of Vav1 in PDAC and, as targeting specific members of the Akt family is a promising therapeutic chance in solid tumors, they suggest that Vav1, by down-modulating Akt2, has potential as a molecular target in PDAC.

Long Noncoding RNA LINC00152 Facilitates the Leukemogenesis of Acute Myeloid Leukemia by Promoting CDK9 Through miR-193a

The vital role of long noncoding RNAs (lncRNAs) on the acute myeloid leukemia (AML) has been increasingly recognized. This study aims to explore the unknown function of lncRNA LINC00152 in the leukemogenesis of AML. LINC00152 is determined to be upregulated in the AML samples, and the overexpression of LINC00152 is also authenticated in the advanced French-American-British (FAB) AML patients and closely correlated with the poor outcome of AML patients. The functional experiments state that knockdown of LINC00152 suppresses the proliferation, accelerates the apoptosis, and induces the cycle arrest of AML cells. The mechanical experiments state that LINC00152 and CDK9 were both targeted by miR-193a with the complementary binding sites at 3'-UTR. Moreover, in the rescue experiments, the enhanced LINC00152 expression could regain the suppression of tumor behavior induced by LINC00152 knockdown. In conclusion, this research reveals the important role of lncRNA LINC00152 in the AML leukemogenesis through targeting miR-193a/CDK9 axis. This finding could indicate the important pathogenesis of ncRNA and the vital roles of epigenetic regulation.

Vav1 is necessary for PU.1 mediated upmodulation of miR-29b in acute myeloid leukaemia-derived cells

It has been recently demonstrated that high pre‐treatment levels of miR‐29b positively correlated with the response of patients with acute myeloid leukaemia (AML) to hypomethylating agents. Upmodulation of miR‐29b by restoring its transcriptional machinery appears indeed a tool to improve therapeutic response in AML. In cells from acute promyelocytic leukaemia (APL), miR‐29b is regulated by PU.1, in turn upmodulated by agonists currently used to treat APL. We explored here the ability of PU.1 to also regulate miR‐29b in non‐APL cells, in order to identify agonists that, upmodulating PU.1 may be beneficial in hypomethylating agents‐based therapies. We found that PU.1 may regulate miR‐29b in the non‐APL Kasumi‐1 cells, showing the t(8;21) chromosomal rearrangement, which is prevalent in AML and correlated with a relatively low survival. We demonstrated that the PU.1‐mediated contribution of the 2 miR‐29b precursors is cell‐related and almost completely dependent on adequate levels of Vav1. Nuclear PU.1/Vav1 association accompanies the transcription of miR‐29b but, at variance with the APL‐derived NB4 cells, in which the protein is required for the association of PU.1 with both miRNA promoters, Vav1 is part of molecular complexes to the PU.1 consensus site in Kasumi‐1. Our results add new information on the transcriptional machinery that regulates miR‐29b expression in AML‐derived cells and may help in identifying drugs useful in upmodulation of this miRNA in pre‐treatment of patients with non‐APL leukaemia who can take advantage from hypomethylating agent‐based therapies.