Downregulation Of PTEN Expression Research Articles

Study on the Effect of the Vaginal Administration of Conjugated Estrogens Cream Combined with Progesterone on the Endometrium of Rats and Its Mechanism of Action.

The purpose of this study was to investigate the impact of conjugated estrogen cream, in conjunction with progesterone, on the endometrium, following vaginal administration, and assess the combined dose-effect relationship with progesterone. Initially, bilateral ovaries from mature, female, Sprague Dawley rats were excised to establish a hypoestrogenic (perimenopausal) model. A conjugated estrogen-progesterone combination cream was administered vaginally for a duration of 12 days. Subsequently, this study used pathological sections, Enzyme-Linked Immunosorbent Assay (ELISA) for pharmacodynamic studies, network pharmacology to explore possible signalling pathways associated with the drug and menopausal syndrome, and partial validation using a real-time quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (ICH). The results demonstrate that, relative to the model group, the conjugated estrogen monotherapy significantly increased the uterine weight coefficients (p < 0.0001) and endometrial thickness (p < 0.001) and upregulated the expression of Cyclin D1 and VEGF. Moreover, this treatment downregulated PTEN expression. The co-administration of progesterone reversed these effects in a dose-dependent manner. Overall, the vaginal administration of a combination of progesterone and conjugated estrogen cream demonstrated the ability to mitigate endometrial hyperplasia induced by conjugated estrogen vaginal cream monotherapy. Furthermore, the effect of progesterone exhibited a dose-dependent response.

Elevated histone deacetylase 10 expression promotes the progression of clear cell renal cell carcinoma by Notch-1-PTEN signaling axis

BackgroundClear cell renal cell carcinoma (ccRCC), the most common pathological subtype of kidney cancer, accounts for approximately 70% to 80% of all cases. Histone deacetylase 10 (HDAC10) belongs to the HDAC class IIb subgroup, one of the histone deacetylases (HDAC) family. Previous studies suggest that HDAC10 may regulate the development of multiple tumor types. The specific molecular mechanisms employed by HDAC10 in the etiology of ccRCC still need to be discovered.MethodsThe analysis included examining HDAC10 expression levels and their clinical importance within a cohort of inpatients and ccRCC patients documented in the Tumor Genome Atlas (TCGA). Moreover, the biological functions and underlying molecular mechanisms of HDAC10 were investigated.ResultsHDAC10 showed increased expression in ccRCC tumor tissues. Subsequent analysis revealed overexpression of HDAC10 was associated with advanced clinical phenotype and unfavorable prognosis. The absence of HDAC10 significantly decreased ccRCC cell proliferation and migration capabilities. Mechanistic research suggests that HDAC10 may promote RCC development by activating the Notch-1 pathway and downregulating PTEN expression levels.ConclusionIn summary, HDAC10 can modulate critical biological processes in ccRCC, including proliferation, migration, and apoptosis. Notably, the Notch-1 pathway and PTEN serve as crucial signaling pathways and target genes through which HDAC10 regulates the progression of ccRCC. These findings offer a novel outlook for ccRCC treatment.

EEF1E1 promotes glioma proliferation by regulating cell cycle through PTEN/AKT signaling pathway.

The cell cycle, a pivotal regulator of cell proliferation, can be significantly influenced by the phosphatase and tensin homolog (PTEN)/AKT signaling pathway's modulation of cyclin-related proteins. In our study, we discovered the crucial role of EEF1E1 in this process, as it appears to downregulate PTEN expression. Furthermore, our findings affirmed that EEF1E1 modulates downstream cell cycle-related proteins by suppressing the PTEN/AKT pathway. Cell cycle assay results revealed that EEF1E1 downregulation stunted the advancement of glioma cells in both the G1 and S phases. A suite of assays-Cell Counting Kit-8, colony formation, and ethyl-2'-deoxyuridine-substantiated that the EEF1E1 downregulation markedly curtailed glioma proliferation. We further validated this phenomenon through animal studies and coculture experiments on brain slices. Our comprehensive investigation indicates that EEF1E1 knockdown can effectively inhibit the glioma cell proliferation by regulating the cell cycle via the PTEN/AKT signaling pathway. Consequently, EEF1E1 emerges as a potential therapeutic target for glioma treatment, signifying critical clinical implications.

Tumor suppressor PTEN regulation by tobacco smoke in lung squamous-cell carcinoma based on bioinformatics analysis

Phosphatase and tensin homolog deleted on chromosome 10 (PTEN), is a tumor suppressor inactivated in a variety of human cancers. PTEN alteration correlates with lung squamous-cell carcinoma (LUSC) histology. However, it is still unclear how tobacco smoke regulates PTEN in LUSC tissues. In this study, we used free online databases and online tools to analyze PTEN expression and the role of smoking on PTEN alteration in patients with LUSC. We validated bioinformatics data by performing RT-PCR analysis using LUSC patient samples. Our results showed a correlation between the downregulation of PTEN in LUSC tissues compared to normal tissues and smoking exposure. In silico results using online platforms suggest that hsa-mir-301a down-regulates PTEN expression level in smoking patients with LUSC. RT-PCR analysis demonstrated that the PTEN expression was significantly decreased, whereas expression of hsa-mir-301a was up-regulated in the smoker cohort of LUSC tissue compared to adjacent non-cancerous tissues. A significant negative correlation between PTEN and hsa-mir-301a levels was observed in tumour tissues in our cohort of LUSC patients. Our results suggest that the downregulation PTEN gene caused by tobacco smoke-mediated increase of hsa-mir-301a may play an important role in LUSC tumorigenesis.

Abstract 3775: Multi-omic spatial analysis with simultaneous detection of small RNAs, mRNAs and proteins using the novel RNAscope™ Plus technology

Abstract Regulatory RNA molecules such as microRNAs (miRNA) and long non-coding RNAs play critical roles in regulating translation of mRNA to protein. Several miRNAs have been implicated in disease initiation and progression, especially in cancer. The regulatory mechanisms of miRNAs and other small RNAs such as antisense oligos (ASOs) and silencing RNAs (siRNA) have been exploited to develop oligonucleotide therapies for 1. undruggable targets, 2. achieving longer-term effects 3. rapid production of therapeutics and 4. lower drug development costs. These therapeutics have the promise to treat debilitating neurodegenerative diseases, rare and inherited disorders. RNA therapies are typically delivered as a part of nanoparticles or a viral vector. Regardless of the delivery mechanism, methods to understand the biodistribution of the vector, transgene expression and cell type identification in a spatial context is crucial to study the safety and efficacy of these therapies. Built on the flagship RNAscope technology, the RNAscope Plus assay can detect 1 small RNA and 3 mRNA targets using TSA-based fluorescent readouts and is compatible with the new fluorescent Vivid™ dyes. Fixed, fresh frozen samples and formalin fixed paraffin embedded (FFPE) tissues are supported by manual and automated workflows using the Leica Bond Rx system. We have leveraged this technology to investigate spatial expression profile of miRNA and associated RNA targets across different tissue types and applications. We can also combine protein detection using a target antibody to visualize cell-type specific markers. This assay was used to demonstrate expression of miRNAs and target genes implicated in tumor initiation, progression, and angiogenesis. Expression of miR-205, associated tumor target genes such as PanCK, PTEN and tumor suppressor TP53 was visualized in head and neck cancer tumors. Downregulation of tumor-suppressor, TP53 resulted in upregulation of miR-205 which downregulates PTEN expression. Pan-CK stained the tumor region in the tissue. Similarly, miR-155 expression was observed in niche areas within breast cancer, head and neck cancer and cervical cancer tumors. Expression of miR-155 demonstrated correlation with high VEGF expression suggesting its role in angiogenesis. This novel platform will enable researchers to visualize regulatory RNA simultaneously with target RNAs, cell-type and morphology markers in intact cells/tissues with single cell resolution. This technology can provide meaningful insights into disease pathology driven by miRNAs as well as assess biodistribution and efficacy of oligonucleotide therapeutics. Citation Format: Anushka Dikshit, Sayantani Basak, Sonali Deshpande, Manvir Sambhi, Li-Chong Wang, Maithreyan Srinivasan. Multi-omic spatial analysis with simultaneous detection of small RNAs, mRNAs and proteins using the novel RNAscope™ Plus technology. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3775.

CircACTR2 attenuates gemcitabine chemoresiatance in pancreatic cancer through PTEN mediated PI3K/AKT signaling pathway

BackgroundRecently, accumulating studies have unveiled that circRNAs exert critical function in a variety of tumor biological processes including chemoresistance. Our previous study has found circACTR2 is significantly down-regulated in acquired gemcitabine (GEM)- resistant pancreatic cancer (PC) cells, which has not been well-explored. Our study aimed to research the function and molecular mechanism of circACTR2 in PC chemoresistance.MethodsqRT-PCR and western blot analysis was performed to detect gene expression. The effect of circACTR2 on PC GEM resistance were examined by CCK-8 and flow cytometry assays. Whether circACTR2 could sponge miR-221-3p and regulate PTEN expression were determined by bioinformatics analysis, RNA pull-down, and Dual-luciferase reporter assay.ResultscircACTR2 was notably down-regulated in a panel of GEM-resistant PC cells lines, and negatively associated with aggressive phenotype and poor prognosis of PC. circACTR2 downregulation contributed to GEM chemoresistance of PC cells with decreased S phase ratio of cell cycle and cell apoptosis, as confirmed by gain- and loss-of-function assays in vitro. In addition, circACTR2 overexpression retarded GEM resistance in vivo. Further, circACTR2 acted as a ceRNA against miR-221-3p, which directly targeted PTEN. The mechanistic studies revealed that loss of circACTR2 promoted GEM resistance in PC through activating the PI3K/AKT signaling pathway by downregulating PTEN expression in a miR-221-3p dependent manner.ConclusionscircACTR2 reversed the chemoresistance of PC cells to GEM through inhibiting PI3K/AKT signaling pathway by sponging miR-221-3p and upregulating PTEN expression.

Synergistic effect of PARP inhibitor and BRD4 inhibitor in multiple models of ovarian cancer.

Ovarian cancer has the highest facility rate among gynaecological tumours. Current therapies including PARP inhibitors have a defect that ovarian tumour is easy to recurrent and become resistant to therapy. To solve this problem, we found that BRD4 inhibitor AZD5153 and PARP inhibitor olaparib had a widespread synergistic effect in multiple models with different gene backgrounds. AZD5153 sensitizes cells to olaparib and reverses the acquired resistance by down-regulating PTEN expression levels to destabilize hereditary materials. In this study, we used the following multiple ovarian cancer models PDX, PDO and 3D/2D cell lines to elucidate the co-effect of AZD5153 and olaparib in vivo and in vitro. The similar results of these models further proved that the mechanism identified was consistent with the biological process occurring in ovarian cancer patients after drug treatment. This consistency between the results of different models suggests the possibility of translating these laboratory research findings into clinical studies towards developing treatments.

Impacts of delta 9-tetrahydrocannabinol against myocardial ischemia/reperfusion injury in diabetic rats: Role of PTEN/PI3K/Akt signaling pathway.

Despite the current optimal therapy, patients with myocardial ischemia/reperfusion (IR) injury still experience a high mortality rate, especially when diabetes mellitus is present as a comorbidity. Investigating potential treatments aimed at improving the outcomes of myocardial IR injury in diabetic patients is necessary. Our objective was to ascertain the cardioprotective effect of delta 9-tetrahydrocannabinol (THC) against myocardial IR injury in diabetic rats and examine the role of phosphatase and tensin homolog (PTEN)/phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway in mediating this effect. Diabetes was induced in male Wistar rats (8-10 weeks old, 200-250 g; n = 60) by a single injection of streptozotocin. The duration of the diabetic period was 10 weeks. During the last 4 weeks of diabetic period, rats were treated with THC (1.5 mg/kg/day; intraperitoneally), either alone or in combination with LY294002, and then underwent IR intervention. After 24 h of reperfusion, infarct size, cardiac function, lactate dehydrogenase (LDH) and cardiac-specific isoform of troponin-I (cTn-I) levels, myocardial apoptosis, oxidative stress markers, and expression of PTEN, PI3K, and Akt proteins were evaluated. THC pretreatment resulted in significant improvements in infarct size and cardiac function and decreases in LDH and cTn-I levels (P < 0.05). It also reduced myocardial apoptosis and oxidative stress, accompanied by the downregulation of PTEN expression and activation of the PI3K/Akt signaling pathway (P < 0.05). LY294002 pretreatment abolished the cardioprotective action of THC. This study revealed the cardioprotective effects of THC against IR-induced myocardial injury in diabetic rats and also suggested that the mechanism may be associated with enhanced activity of the PI3K/Akt signaling pathway through the reduction of PTEN phosphorylation.

Long non-coding RNA BC002811 Promotes Gastric Cancer Metastasis by Regulating SOX2 Binding to the PTEN Promoter.

There is increasing evidence that long non-coding RNAs (lncRNAs) are involved in the pathogenesis and progression of gastric cancer (GC), however, the underlying mechanisms remain poorly understood. In this study, we identified lncRNA BC002811 as a critical regulator of GC development and progression. BC002811 was upregulated in GC tissues and cell lines, and that high expression of BC002811 was indicative of a reduction in overall survival of GC patients. Our research reveals that BC002811 promoted GC cell proliferation, migration, invasion, and inhibition of apoptosis in vitro, as well as accelerated tumor growth and metastasis in vivo. We also found that BC002811 upregulated MMP2 and MMP9 and promoted GC cell metastasis partially through downregulating PTEN expression. BC002811 may act as a molecular decoy for the transcription factor SOX2, thereby inhibiting the transcription of PTEN by blocking SOX2 binding to the PTEN promoter. Our study advances the understanding of the role of BC002811 in the pathogenesis of GC and provides new molecular targets for therapeutic intervention against GC metastasis.

Morphine-mediated release of astrocyte-derived extracellular vesicle miR-23a induces loss of pericyte coverage at the blood-brain barrier: Implications for neuroinflammation.

Opioids such as morphine are the most potent and efficacious drugs currently available for pain management. Paradoxically, opioids have also been implicated in inducing neuroinflammation and associated neurocognitive decline. Pericytes, a critical component of the neurovascular unit (NVU), are centrally positioned between endothelial cells and astrocytes, maintaining function of the blood-brain barrier (BBB) nd regulating neuroinflammation by controlling monocyte influx under various pathological conditions. The role of pericytes in morphine-mediated neuroinflammation however, has received less attention, especially in the context of how pericytes crosstalk with other central nervous system (CNS) cells. The current study was undertaken to examine the effect of miRNAs released from morphine-stimulated human primary astrocyte-derived extracellular vesicles (morphine-ADEVs) in mediating pericyte loss at the blood-brain barrier, leading, in turn, to increased influx of peripheral monocytes. Our findings suggest that the heterogeneous nuclear ribonucleoprotein complex A2/B1 (hnRNP A2/B1) plays role in morphine-mediated upregulation and release of miR-23a in ADEVs, and through action of morphine via mu opioid receptor.We further demonstrated that miR-23a in morphine-ADEVs could be taken up by pericytes, resulting in downregulation of PTEN expression, ultimately leading to increased pericyte migration. Furthermore, both overexpression of PTEN and blocking the miR-23a target site at PTEN 3UTR (by transfecting miR-23a-PTEN target protector), attenuated morphine-ADEV-mediated pericyte migration. We also demonstrated that in the microvessels isolated from morphine-administered mice, there were fewer PDGFβR + pericytes co-localizing with CD31+ brain endothelial cells compared with those from saline mice. In line with these findings, we also observed increased loss of pericytes and a concomitantly increased influx of monocytes in the brains of morphine-administered pericyte-labeled NG2-DsRed mice compared with saline mice. In conclusion, our findings indicate morphine-ADEVs mediated loss of pericyte coverage at the brain endothelium, thereby increasing the influx of peripheral monocytes in the central nervous system, leading to neuroinflammation.

The interaction of hsa_circ_0002594 and eIF4A3 promotes T-helper 2 cell differentiation by the regulation of PTEN.

T helper (Th) 2 cell-medicated immune response participates in various immune diseases, especially in asthma. Circ_0002594 has been reported to be up-regulated in asthmatic patients, and was higher in Th2-high subgroups, but the specific mechanisms by which circ_0002594 regulating Th2 cells were still unclear. Here, we found that circ_0002594 was significantly up-regulated in CD4+ T cells of asthmatic patients. Circ_0002594 overexpression elevated Th2-related cytokine IL-4 production and reduced Th1-related cytokine INF-γ production, promoting Th2 cell differentiation, while circ_0002594 loss resulted in the opposite results. Additionally, eIF4A3 overexpression reversed the effects of circ_0002594 on the production of INF-γ, IL-4 and Th1/Th2 ratio by interacting with circ_0002594. Moreover, circ_0002594 interacted with eIF4A3 to reduce PTEN mRNA stability, thus down-regulating PTEN mRNA expression. Furthermore, eIF4A3 overexpression markedly reversed the significant down-regulation of PTEN protein level and the activation of PI3K/AKT/mTOR pathway in CD4+ T cells transfected with Lv-circ_0002594, suggesting the involvement of circ_0002594/eIF4A3/PTEN axis in the activation of PI3K/AKT/mTOR pathway. Also, rapamycin (the mTOR inhibitor) dramatically reversed the promotion effects of circ_0002594 overexpression on Th2 cells. In conclusion, our study demonstrated that circ_0002594 interacted with eIF4A3 to reduce PTEN mRNA stability, down-regulating PTEN expression, thereby activating the PI3K/AKT/mTOR pathway to promote Th2 cell differentiation. Our work may highlight novel insights into the molecular mechanism of circ_0002594 in regulating Th2 cell differentiation in asthma.

MicroRNA-495-3p diminishes doxorubicin-induced cardiotoxicity through activating AKT.

Doxorubicin (Dox) is a broad‐spectrum antitumour agent; however, its clinical application is impeded due to the cumulative cardiotoxicity. The present study aims to investigate the role and underlying mechanisms of microRNA‐495‐3p (miR‐495‐3p) in Dox‐induced cardiotoxicity. Herein, we found that cardiac miR‐495‐3p expression was significantly decreased in Dox‐treated hearts, and that the miR‐495‐3p agomir could prevent oxidative stress, cell apoptosis, cardiac mass loss, fibrosis and cardiac dysfunction upon Dox stimulation. In contrast, the miR‐495‐3p antagomir dramatically aggravated Dox‐induced cardiotoxicity in mice. Besides, we found that the miR‐495‐3p agomir attenuated, while the miR‐495‐3p antagomir exacerbated Dox‐induced oxidative stress and cellular injury in vitro. Mechanistically, we demonstrated that miR‐495‐3p directly bound to the 3′‐untranslational region of phosphate and tension homology deleted on chromosome ten (PTEN), downregulated PTEN expression and subsequently activated protein kinase B (PKB/AKT) pathway, and that PTEN overexpression or AKT inhibition completely abolished the cardioprotective effects of the miR‐495‐3p agomir. Our study for the first time identify miR‐495‐3p as an endogenous protectant against Dox‐induced cardiotoxicity through activating AKT pathway in vivo and in vitro.

Effects of adenovirus-mediated shRNA down-regulates PTEN expression on fibril-binding proteins vinculin, filamin A and cortactin in activated hepatic stellate cells

Objective: To investigate the effect of adenovirus-mediated shRNA down-regulating phosphatase and tensin homolog deleted on chromosome 10 (PTEN) expression on vinculin, filamin A, and cortactin in activated hepatic stellate cells (HSCs). Methods: Activated rats hepatic stellate cell line (HSC-T6) was cultured in vitro. Recombinant adenovirus Ad-shRNA/PTEN carrying PTEN targeted RNA interference sequence [short hairpin RNA (shRNA)] and empty control virus Ad-GFP were transfected into HSCs. The PTEN mRNA and protein expression of HSCs in each group were detected by real-time fluorescence quantitative PCR and Western blot. The expressional change of vinculin, filamin A and cortactin in HSCs of each group were detected by confocal laser scanning immunofluorescence microscope. Image-pro plus 6.0 software was used for image analysis and processing. The integrated optical density (IOD) of the fluorescence protein expression was measured. The experiment was divided into three groups: control group (DMEM instead of adenovirus solution in the adenovirus transfection step), Ad-GFP group (transfected with empty virus Ad-GFP only expressing green fluorescent protein), and Ad-shRNA/PTEN group (recombinant adenovirus Ad-shRNA/PTEN carrying shRNA targeting PTEN and expressing green fluorescent protein). One-way analysis of variance was used for comparison of mean value among the three groups, and LSD-test was used for comparison between the groups. Results: shRNA targeted PTEN was successfully transfected and the expression of PTEN mRNA and protein in HSC (P < 0.05) was significantly down-regulated. HSCs vinculin was mainly expressed in the cytoplasm. HSCs vinculin fluorescence IOD in the Ad-shRNA/PTEN group (19 758.83 ± 1 520.60) was higher than control (7 737.16 ± 279.93) and Ad-GFP group (7 725.50 ± 373.03) (P < 0.05), but there was no statistically significant difference between control group and Ad-GFP group (P > 0.05). There was no statistically significant difference in the fluorescence IOD of Filamin A among the three groups (P > 0.05), but the subcellular distribution of Filamin A among the three groups were changed. Filamin A in the Ad-shrNA /PTEN HSC group was mainly distributed in the cytoplasm. Filamin A HSC was mainly located in the nucleus.The filamin A HSC in the control group and Ad-GFP group was mainly located in the nucleus. The nucleocytoplasmic ratio of Filamin A in the AD-shrNA /PTEN group (0.60 ± 0.15) was significantly lower than control group (1.20 ± 0.15) and Ad-GFP group (1.08 ± 0.23), P < 0.05. but there was no statistically significant difference in filamin A nucleocytoplasmic ratio of HSC between the control group and the Ad-GFP group (P > 0.05). Cortactin HSCs in the three groups was mainly distributed in the cytoplasm. The cortactin fluorescence IOD of HSCs in the Ad-shRNA/PTEN group was significantly higher than control group (22 959.94 ± 1 710.42) and the Ad-GFP group (22 547.11 ± 1 588.72 ) (P < 0.05), while there was no statistically significant difference in the IOD of cortactin fluorescence in HSCs between the control group and the Ad-GFP group (P > 0.05). Conclusion: The down-regulation of PTEN expression raises the expression of microfilament-binding protein vinculin and cortactin, and changes the subcellular distribution of another microfilament binding protein filamin A, that is, translocation from nucleus to the cytoplasm in activated HSC in vitro.

PTEN promoter methylation predicts 10-year prognosis in hormone receptor-positive early breast cancer patients who received adjuvant tamoxifen endocrine therapy

PurposeThere remain a lack of biomarkers for endocrine therapy resistance in patients with breast cancer (BC), which is proving to be a great challenge. In vitro experiments have shown that downregulation of PTEN expression leads to resistance to tamoxifen (TAM) in BC cells. We aimed to investigate the predictive role of tumor PTEN promoter methylation and PTEN expression in long-term survival after TAM adjuvant therapy in patients with early-stage BC.MethodsFrom 2001 to 2013, 105 patients with stage I–III BC who were treated with standardized adjuvant TAM for 5 years or until relapse in West China Hospital (WCH) were enrolled in this study. PTEN expression and DNA methylation of three specified sequences from the PTEN promoter in primary tumors were measured using immunohistochemistry and pyrosequencing. A cohort of 159 hormone receptor-positive patients receiving TAM treatment from The Cancer Genome Atlas (TCGA) database was used for verification.ResultsMedian follow-up time for the WCH cohort was 141.7 months. The low, moderate, and high PTEN expression groups had differing 10-year disease-free survival (DFS) (42.3%, 55%, 81%, respectively, P = 0.027) and overall survival (OS) rates (65%, 84.2%, 90.5%, respectively, P = 0.027). Higher methylation levels of the second sequence (− 819 to − 787 bp), rather than the first (− 1143 to − 1107 bp) or third sequence (− 663 to − 593 bp), independently increased the risk of disease recurrence (hazard ratio = 2.60) and death (hazard ratio = 3.79) in the WCH cohort, according to multivariate Cox regression analysis. Importantly, out of the five CpG islands located within this sequence, only high methylation of the − 796 CpG island predicted shorter DFS and OS. In TCGA validation cohort, there was also a trend of higher methylation of the − 796 CpG island correlating with shorter disease-free intervals, with borderline significance (P = 0.057).ConclusionLow PTEN expression and high methylation of its promoter (sequence − 819 to − 787 bp) in tissue predict poor DFS and OS in hormone receptor-positive early BC patients who received adjuvant TAM.

Mechanism of IDH1-R132H mutation in T cell acute lymphoblastic leukemia mouse model via the Notch1 pathway

T-cell acute lymphoblastic leukemia (T-ALL) is a clonal malignant disease. Isocitrate Dehydrogenase 1-R123 (IDH1-R132 H) is related to T-ALL progression. This study explored the role of IDH1-R132H in T-ALL. Molt-4 cells with IDH1-R132H mutation were constructed by retroviral transfection of IDH1-R132H and T-ALL xenotransplantation mouse model was established by injection of Molt-4 cells through the tail vein. Infiltration of the liver, spleen, and bone marrow and the percentage of CD45-positive T-ALL cells in them were detected. Cell proliferation, apoptosis, and invasion were evaluated after the intervention of Notch1, PTEN, or PI3K expression. The leukocyte number was increased, the spleen was enlarged, infiltration in bone marrow, spleen, and liver tissue was worsened and the percentage of hCD45-positive T-ALL cells was increased by IDH1-R132H mutation, which promoted T-ALL deterioration. IDH1-R132H mutation promoted proliferation, invasion, and inhibited apoptosis of T-ALL cells, which were reversed by inhibition of Notch1. IDH1-R132H mutation upregulated HES1 expression and downregulated PTEN expression by activating the Notch1 pathway, while inhibition of Notch1 reversed these changes. PTEN inhibited the PI3K/AKT pathway activation. PTEN overexpression reversed IDH1-R132H mutation effect on promoting malignant behaviors of T-ALL cells. IDH1-R132H mutation inhibited PTEN expression by activating the Notch1/HES1 pathway, activated the PI3K/AKT pathway, thus promoting malignant behaviors of T-ALL cells.

Exosomes Derived From Alveolar Epithelial Cells Promote Alveolar Macrophage Activation Mediated by miR-92a-3p in Sepsis-Induced Acute Lung Injury

Acute lung injury (ALI) induced by sepsis is characterized by disruption of the epithelial barrier and activation of alveolar macrophages (AMs), which leads to uncontrolled pulmonary inflammation. However, effective treatments for ALI are unavailable. The exact mechanism by which the initial mediator of alveolar epithelial cells (AECs) induces inflammation remains elusive. Here we investigated the roles of AEC-derived exosomes in AM activation and sepsis-induced ALI in vivo and in vitro. Cecal ligation and puncture (CLP) was utilized to establish septic lung injury model in rats. The effect of exosomal inhibition by intratracheal GW4869 administration on lung injury was investigated. To assess the effects of AEC-derived exosomes on ALI, we treated the rat alveolar epithelial cell line RLE-6TN with LPS to induce cell damage. Exosomes from conditioned medium of LPS-treated AECs (LPS-Exos) were isolated by ultracentrifugation. The miRNAs in LPS-Exos were screened by miRNA expression profile analysis. The effects of miR-92a-3p on the function of AMs were studied. We found that intratracheal GW4869 administration ameliorated lung injury following CLP-induced ALI. LPS-Exos were taken up by AMs and activated these cells. Consistently, administration of LPS-Exos in rats significantly aggravated pulmonary inflammation and alveolar permeability. Moreover, miR-92a-3p was enriched in LPS-Exos and could be delivered to AMs. Inhibition of miR-92a-3p in AECs diminished the proinflammatory effects of LPS-Exos in vivo and in vitro. Mechanistically, miR-92a-3p activates AMs along with pulmonary inflammation. This process results in activation of the NF-κB pathway and downregulation of PTEN expression, which was confirmed by a luciferase reporter assay. In conclusion, AEC-derived exosomes activate AMs and induce pulmonary inflammation mediated by miR-92a-3p in ALI. The present findings revealed a previously unidentified role of exosomal miR-92a-3p in mediating the crosstalk between injured AEC and AMs. miR-92a-3p in AEC exosomes might represent a novel diagnostic biomarker for ALI, which may lead to a new therapeutic approach.

The Biological Effects of Forkhead Box Protein A2 (FOXA2) on Cervical Cancer Cells by Regulating Phosphatase and Tensin Homolog (PTEN)

The pathogenesis of cervical cancer is complex and FOX family is abnormally expressed in several diseases. FOXA2’s role in cervical cancer remains unclear. FOXA2 level in cervical cancer and adjacent normal tissues was detected. Cervical cancer Hela cells were divided into control group, FOXA2 group and FOXA2 siRNA group followed by analysis of FOXA2 level by Real time PCR and western blot, cell survival by MTT assay, cell migration and invasion, and PTEN expression by western blot. The cells were divided into NC group, FOXA2 group and FOXA2+PTEN inhibitor group followed by analysis of cell behaviors by flow cytometry and PTEN expression by western blot. FOXA2 was significantly downregulated in cancer tissues compared with adjacent tissues (P&lt;0.05) and associated with tumor size and FIGO stage (P&lt;0.05), but not with vascular invasion, pathological grade and lymph node metastasis. Overexpression of FOXA2 inhibited Hela cell proliferation, migration and invasion, and increased PTEN expression (P&lt;0.05), which were all significantly reversed after inhibition of FOXA2 (P&lt;0.05). The addition of PTEN inhibitor to Hela cells overexpressing FOXA2 reversed the effect of FOXA2 on Hela cells and down-regulated PTEN expression (P&lt;0.05). FOXA2 is downregulated in cervical cancer, which is related to tumor size and FIGO stage. Overexpression of FOXA2 inhibits cell behaviors by regulating PTEN.

Dysregulation of LINC00470 and METTL3 promotes chemoresistance and suppresses autophagy of chronic myelocytic leukaemia cells.

Cytoplasmic lncRNAs have been found to directly interact with target mRNAs and regulate their stability. In this study, we aimed to study the molecular mechanism underlying the function of m6A as a central regulator in chemoresistance and CML proliferation. In this study, we established three mice groups (control group, ADR‐R group and ADR‐R + shLINC00470 group). We detected PTEN mRNA expression in the presence of LINC00470 in the mice models, as well as in the KCL22 and K562 cells. LINC00470 was significantly enriched for PTEN mRNA to exhibit a negative regulatory relationship between LINC00470 and PTEN mRNA. However, the alteration of LINC00470 had no effect on the luciferase activity of PTEN promoter, while the half‐life of PTEN mRNA was affected. It was further validated that LINC00470 down‐regulated PTEN expression by positively regulating the m6A modification of PTEN mRNA via RNA methyltransferase METTL3. Moreover, the relative expression of LC3II, Beclin‐1, ATG7 and ATG5 was all decreased in cells treated with LINC00470, and down‐regulated PTEN expression was observed in chemo‐resistant cells, while the expression of PTEN was rescued by the transfection of shMETTL3 into chemo‐resistant cells. Moreover, the knockdown of METTL3 also restored the normal level of PTEN m6A modification and LINC00470 expression in chemo‐resistant cells. In conclusion, our results demonstrated the molecular mechanism underlying the effect of LINC00470 on CML by reducing the PTEN stability via RNA methyltransferase METTL3, thus leading to the inhibition of cell autophagy while promoting chemoresistance in CML.

Effect of miR-21 on Renal Fibrosis Induced by Nano-SiO₂ in Diabetic Nephropathy Rats via PTEN/AKT Pathway.

MicroRNAs are a type of non-coding single-stranded RNA that can mediate target mRNA degradation or inhibit target mRNA translation, thereby regulating target gene expression and have an important role in physiological and pathological processes. At present, miRs have been confirmed to be closely related to kidneys and kidney diseases, and have been involved in the occurrence, development and prognosis of renal fibrosis. Now we review the research progress of miRs in renal fibrosis in recent years, and provide references for the future diagnosis and treatment of renal fibrosis. The incidence of diabetic nephropathy (DN) is increasing year by year, the pathogenesis is complicated, and renal fibrosis occurs during the progress of the disease, which is very difficult to treat. The protein encoded by the PTEN gene has lipid phosphatase and protein phosphatase activity and is the PTEN/AKT and FAK pathway important negative regulators. It can play an anti-fibrotic effect by negatively regulating the PTEN/AKT pathway. Studies show that during the pathogenesis of DN, the expression of PTEN protein is reduced, and the PI3K/AKT pathway is activated to exert multiple fibrotic effects, but affect PTEN. The regulatory factors of expression are still not clear; moreover, the specific mechanism of the decrease in PTEN protein expression in DN pathogenesis. Therefore, this study intends to Intervention of the expression level of miRs in renal tissues, to study its regulation of PTEN and its effect on renal fibrosis, and at the same time, observe the effects on renal tubular epithelial cell phenotype and fibrotic lesions under high glucose conditions by up-regulating and down-regulating PTEN expression. Further elucidate the pathogenesis of DN renal fibrosis, and explore new effective targets for the prevention and treatment of DN.

MicroRNA-101 inhibits growth and metastasis of human ovarian cancer cells by targeting PI3K/AKT.

IntroductionOvarian cancer is the most frequent cause of gynecological cancer related mortality in woman. This study was designed to investigate the role and therapeutic potential of miRNA-101 in ovarian cancer.Material and methodsExpression analysis was carried out by real-time quantitative polymerase chain reaction. Transfections were performed with the help of Lipofectamine 2000 reagent. AO/EB and annexin V/PI staining was used to detect apoptosis and flow cytometry was used for cell cycle analysis. Western blotting was employed for cell cycle analysis.ResultsIt was found that miRNA-101 was significantly down-regulated in ovarian cancer cells. The over-expression of miRNA-101 causes a significant decrease in the viability of ovarian cancer cells via the initiation of apoptosis and sub-G1 arrest of OVACAR-3 cells. It was indicated that PTEN was the potential target of miRNA-101 in OVACAR-3 cells. There was 4.5-fold up-regulation of PTEN expression in ovarian cancer cell lines and the over-expression of miRNA-101 in OVACAR-3 cells resulted in the down-regulation of PTEN expression. The inhibition of PTEN in the OVACAR-3 cells arrested the proliferation of these cells. The over-expression of miRNA-101 causes significant down-regulation in PI3K and AKT expression of OVACAR-3 cells.ConclusionsIt can be concluded that miRNA-101 acts as a tumor suppressor which may be beneficial in the treatment of ovarian cancer.