PTEN Levels Research Articles

The oncogenic axis YAP/MYC/EZH2 impairs PTEN tumor suppression activity enhancing lung tumorigenicity

The tumor suppressor PTEN (phosphatase and tensin homolog deleted in chromosome 10) is genetically deleted or downregulated in many cancer types. Loss of PTEN protein expression is frequently found in lung cancer while genetic alterations are less abundant. PTEN expression is regulated at multiple genetic and epigenetic levels and even partial reduction of its expression increases cancer occurrence. We show that YAP and TAZ cooperate with EZH2, and MYC to transcriptionally repress onco-suppressor genes, including PTEN, in non-small cell lung cancer (NSCLC) cells. YAP/TAZ-EZH2-MYC transcriptional regulators form a nuclear complex that represses PTEN transcription, while their combinatorial targeting restores PTEN expression, attenuates NSCLC cell growth, and prevents compensatory responses induced by single treatments. Datasets analysis of NSCLC patients revealed that PTEN expression is negatively correlated to YAP/TAZ, EZH2 and MYC and that low expression of PTEN is predictive of poor prognosis, especially at earlier stages of the disease. These findings highlight the repressive role of the YAP/TAZ-EZH2-MYC axis on tumor-suppressor genes and offer a potential therapeutic strategy for lung cancer patients with low PTEN levels.

Shisandra Decoction Alleviates Parkinson's Disease Symptoms in a Mouse Model Through PI3K/AKT/mTOR Signalling Pathway.

The present study aimed to characterize neuroprotective effects of Schisandra Decoction (Sch D) treatment in a mouse model of Parkinson's disease (PD), and to explore underlying mechanisms focused on the mammalian target of rapamycin (mTOR) signaling pathway. 50 male C57 BL/6 mice were randomly assigned to either control (n = 10) or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model (n = 40) groups. PD mice were further divided into four groups of ten mice each: MPTP group, LY294002 group, Sch D group, and LY2940002 + Sch D group. Mice from each group were assessed in pole climbing, rotary rod and open field tests. Brain Tyrosine hydroxylase (TH) protein was observed using immunohistochemistry. mRNA levels of PTEN, PI3K and LC3 in brain tissue were measured using RT-PCR. Protein levels of PTEN, PI3K, Akt, p-Akt, mTOR, p-mTOR, p70s6K, p62, LC3II / I, α-synuclein (α-syn), TH in brain tissue were assessed by Western blotting (WB). In behavioral tests, PD mice treated with Sch D showed reduced pole climbing time, longer rotarod duration, and greater distance traveled. In terms of neuroprotection, PD mice in the Sch D group exhibited higher levels of TH protein and enhanced α-syn clearance. Regarding autophagy, compared to the control group, mice in the MPTP group had elevated PTEN protein expression, which inhibited PI3K, p-AKT/AKT, and p-mTOR/mTOR protein levels, decreased LC3II/I protein expression, and increased P62 protein expression. Treatment with Sch D reversed these effects. Sch D reduces α-syn aggregation in the brains of MPTP-induced PD model mice, exerts neuroprotective effects, and improves motor function. Additionally, Sch D inhibits autophagy through the PI3K/AKT/mTOR pathway. The neuroprotective effect of Sch D may involve the suppression of abnormal autophagy and its antioxidant properties, which indirectly reduces α-syn accumulation. Future studies should assess the impact of Sch D on oxidative stress markers to evaluate its antioxidant effects.

Inhibition of MiR-155 Using Exosomal Delivery of Antagomir Can Up-Regulate PTEN in Triple Negative Breast Cancer.

The most aggressive form of breast cancer (BC) is Triple-Negative BC (TNBC), with the poorest prognosis, accounting for nearly 15% of all cases. Since there is no effective treatment, novel strategies, especially targeted therapies, are essential to treat TNBC. Exosomes are nano-sized microvesicles derived from cells and transport various intracellular cargoes, including microRNAs (miRNAs). MiRNAs, small non-coding RNA, are an influential factor in the development of cancerous transformations in cells. Bioinformatics analysis of genes related to TNBC revealed that PTEN plays a crucial role in the disease. Relative expression of this gene was analyzed with RT-qPCR in 14 TNBC clinical samples. Electroporation was used to load miRNA antagomir into exosomes extracted from the conditioned medium. Then, the expression of miR-155 and PTEN was evaluated in MDA-MB-231 cells treated with antagomir-loaded exosomes. Based on the bioinformatics analysis, miR-155 is a potent inhibitor of PTEN. Following treatment with antagomir-loaded exosomes, RT-qPCR showed significantly reduced miR- 155 and increased PTEN levels in MDA-MB-231 cells. Based on the results of this study, exosomes can be effectively used as a cargo of oligonucleotides like miRNA mimics and antagomirs in targeted therapies.

Circulating mRNA Expression of VEGF, PTEN, and SOCS1 as Potential Prognostic Predictor for Nasopharyngeal Carcinoma Progression.

The molecular mechanisms underlying nasopharyngeal carcinoma (NPC) progression remain poorly understood. In particular, the roles of circulating mRNAs encoding key regulatory proteins have yet to be explored. This study aimed to identify NPC-associated expression signatures of circulating VEGF, PTEN, and SOCS1 mRNAs and their potential as biomarkers. A case-control study was conducted comprising 160 nasopharyngeal carcinoma (NPC) patients and 80 controls, from whom peripheral blood samples. Total RNA was extracted and the levels of VEGF, PTEN, and SOCS1 mRNAs were quantified using reverse transcription quantitative PCR (RT-qPCR). Relative expression was calculated using the 2-ΔΔCt method. Bioinformatic analyses, including GeneMANIA, Gene Ontology (GO), and KEGG pathway analysis, were performed to predict the functional roles and interactions of these mRNAs. We identified significantly increased circulating VEGF mRNA in lymph node metastases (1.66-fold, p<0.05) and elevated SOCS1 mRNA in late-stage NPC (20-fold, p<0.05). PTEN mRNA was reduced 4.26-fold in NPC patients. These data suggest that circulating VEGF, PTEN, and SOCS1 mRNAs represent signatures of NPC progression and can potentially be biomarkers. Network analyses implicate these mRNAs in mechanisms enabling NPC pathogenesis. Our study reveals NPC-associated expression changes of circulating VEGF, PTEN, and SOCS1 mRNAs. These molecular signatures may serve as biomarkers during NPC progression and provide insights into underlying mechanisms. Further validation of their utility as prognostic indicators of NPC is warranted.

Effects of Petasitin as Natural Extract on Proliferation and Pathological Changes of Pediatric Neuroblastoma SK-N-SH Cells

This research was developed to investigate the impact and mechanisms of petasitin as natural extract on the proliferation and pathological changes of pediatric neuroblastoma SK-N-SH cells. The sample cells were selected as experimental materials and randomly rolled into a control (Ctrl), a low-dose (LD), a medium-dose (MD), and a high-dose (HD) group, which were subjected to regular culture, 0.5, 1.5, and 5 μM/L petasitin for 12 hours, respectively. Meanwhile, the cell proliferation was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Flow cytometry (FCT) was employed to assess the cycle progression and apoptosis of SK-N-SH cells, while Hoechst 33258 fluorescent staining was applied to observe the nuclear changes. Meanwhile, the real-time quantitative PCR (RT-qPCR) was applied to measure the mRNA levels of PI3K, PTEN, AKT1, and mTOR genes in SK-N-SH cells. Western blot was conducted to determine the protein expression levels (PELs) of p-PI3K, PI3K, p-Akt, Akt, p-mTOR, and mTOR in SK-N-SH cells. The results revealed that after treatment for 48 and 72 hours, the optical density (OD) values in the petasitin treatment groups were lower and exhibited great differences to those in the Ctrl group (P &lt; 0.05), while inhibition rates (IRs) were higher (P &lt; 0.05). Furthermore, the petasitin treatment groups exhibited an obvious increase in the G1/G0 cell cycle ratio (CCR) and a great decrease in S and G2/M phase CCR (P &lt; 0.05). Moreover, the apoptotic rates in the petasitin treatment groups were much higher at different time points, showing observable differences with P &lt; 0.05. Besides, the Hoechst 33258 staining positivity rates (PRs) of SK-N-SH cell nuclei in the petasitin treatment groups were higher and presented great differences with P &lt; 0.05 to those in the Ctrl group. In addition, the cells in petasitin treatment groups exhibited greatly downshifted mRNA levels of PI3K and AKT1 and obviously elevated PTEN (all P &lt; 0.05). PELs of PI3K, AKT1, and mTOR exhibited no great differences (P &gt; 0.05), but phosphorylation levels of p-PI3K, p-Akt, and p-mTOR were decreased in the petasitin treatment groups, presenting great differences with P &lt; 0.05. Together, these results suggested that petasitin exerted a suppressive role in proliferation and promote the apoptosis of pediatric SK-N-SH cells by adjusting PI3K-Akt-mTOR signaling pathway (SPW).

Molecular mechanisms of PI3K isoform dependence in embryonic growth.

The phosphoinositide 3-kinase (PI3K) pathway is an important signaling mechanism for cell proliferation and metabolism. Mutations that activate PIK3CA may make cells p110α dependent, but when phosphatase tensin homolog (PTEN) is lost, the p110β isoform of PI3Ks becomes more important. However, the exact mechanism underlying the prevalence of p110s remains unclear. In this study, our aim was to elucidate the processes behind PI3K isoform dependency in a cellular model of embryonic development. In order to understand PI3K isoform prevalence, mouse embryonic fibroblasts (MEFs) were used and p110β, PTEN and Rac1 activity was modulated using retroviral plasmids. Expression levels and cellular growth were assessed by performing immunoblots and crystal violet assays. The levels of PTEN had only a partial effect on the prevalence of PI3K isoforms in MEFs. The dependency on p110α diminished when PTEN was depleted. Of note, when PTEN expression was repressed, there was no full transition in dependency from one PI3K isoform to the other. Interestingly, the viability of PTEN-depleted MEFs became less dependent on p110α and more dependent on p110β when p110β was overexpressed. Nevertheless, the overexpression of p110β in conjunction with PTEN knock-downs did not result in a complete shift of isoforms in PI3Ks. Finally, we investigated Rac1 activation with a mutant allele and determined a more potent increase in p110β prominence in MEFs. These findings suggest that multiple cellular parameters, including PTEN status, PI3K isoform levels, and Rac1 activity, combine to influence PI3K isoform prevalence, rather than a single determinant.

PTEN Regulates Myofibroblast Activation in Valvular Interstitials Cells based on Subcellular Localization.

Aortic valve stenosis (AVS) is characterized by altered mechanics of the valve leaflets, which disrupts blood flow through the aorta and can cause left ventricle hypotrophy. These changes in the valve tissue result in activation of resident valvular interstitial cells (VICs) into myofibroblasts, which have increased levels of αSMA in their stress fibers. The persistence of VIC myofibroblast activation is a hallmark of AVS. In recent years, the tumor suppressor gene phosphatase and tensin homolog (PTEN) has emerged as an important player in the regulation of fibrosis in various tissues (e.g., lung, skin), which motivated us to investigate PTEN as a potential protective factor against matrix-induced myofibroblast activation in VICs. In aortic valve samples from humans, we found high levels of PTEN in healthy tissue and low levels of PTEN in diseased tissue. Then, using pharmacological inducers to treat VIC cultures, we observed PTEN overexpression prevented stiffness-induced myofibroblast activation, whereas genetic and pharmacological inhibition of PTEN further activated myofibroblasts. We also observed increased nuclear PTEN localization in VICs cultured on stiff matrices, and nuclear PTEN also correlated with smaller nuclei, altered expression of histones and a quiescent fibroblast phenotype. Together, these results suggest that PTEN not only suppresses VIC activation, but functions to promote quiescence, and could serve as a potential pharmacological target for the treatment of AVS.

Huangqin Qingrechubi Capsule alleviates inflammation and uric acid and lipid metabolism imbalance in rats with gouty arthritis by inhibiting the PTEN/PI3K/AKT signaling pathway

To investigate the effects of Huangqin Qingrechubi Capsule (HQC) on inflammation and uric acid and lipid metabolism in rats with gouty arthritis (GA) and its mechanism. SD rat models of GA established by injecting monosodium urate into the right ankle joint were treated with saline, colchicine and HQC at low, medium and high doses (n=10) by gavage for 7 days. Toe swelling of the rats was detected at 4, 8, 24, 48 and 72 h after modeling, and synovial histological changes were observed with HE staining. Serum levels of interleukin-10 (IL-10), IL-18, tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1), adiponectin, leptin, resistin and visfatin were measured by ELISA, and the levels of high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), total cholesterol (TC), and uric acid (BUA) were detected. RTqPCR and Western blotting were used to detect the mRNA expressions of phosphatase and tensin homolog (PTEN), phosphatidylinositol-3-kinase (PI3K) and protein kinase B (AKT) and the protein expressions of PTEN, PI3K, p-PI3K, AKT and p-AKT. The rat models of GA showed obvious toe swelling, which reached the peak level at 48 h. HE staining revealed massive inflammatory cell infiltration and synovial tissue hyperplasia. The rat models showed significantly increased expressions of TNF-α, TGF-β1, IL-18, TC, TG, leptin, resistin and visfatin, BUA, p-PI3K, and p-AKT and lowered levels of IL-10, APN, HDL-C, and PTEN. Treatment with HQC and colchicine obviously improved these changes and alleviated synovial pathologies and toe swelling in the rat models. HQC can improve inflammation and correct the imbalance of uric acid and lipid metabolism in GA rats possibly by inhibiting the PTEN/PI3K/AKT signaling pathway.

Buyang Huanwu Decoction attenuates cerebral ischemia-reperfusion injury in rats via miR-26a-5p mediated PTEN/PI3K/Akt signaling pathway

This study aims to investigate the mechanism of Buyang Huanwu Decoction in treatment of cerebral ischemia-reperfusion injury in rats. A total of 180 SD rats were randomly divided into 5 different groups: sham group, model group, Buyang Huanwu Decoction group, Buyang Huanwu Decoction + miR-26a-5p agomir(agomir) group, Buyang Huanwu Decoction + miR-26a-5p agomir negative control(agomir NC) group. There were 36 rats in each group. Each group was then subdivided into three subgroups for the duration of reperfusion(3, 7, 14 d). A ligature-induced middle cerebral artery occlusion(MCAO) model was carried out on all groups other than sham group. Reperfusion was performed following ischemia for 90 min. Buyang Huanwu Decoction group, agomir group, and agomir NC group were given Buyang Huanwu Decoction twice daily by gavage 24 h after the formation of the model. Sham group and model group were given an equal amount of physiological saline by gavage until the day before sacrifice. At 24 h after ischemia induction, miR-26a-5p agomir was injected into the lateral ventricle in agomir group, miR-26a-5p NC in agomir NC group, and equal amounts of physiological saline in the other groups. 24 h after ischemia induction, BrdU was intraperitoneally injected once daily until the day before sacrifice. Modified neurological severity score(mNSS) was used to evaluate neurological deficits, 2,3,5-triphenyltetrazolium chloride(TTC) staining was used to determine the cerebral infarct volume, TUNEL staining was used to assess the apoptosis of parenchymal ischemic brain tissue, and double immunofluorescence staining was used to examine BrdU/NeuN double positive neurons in the parenchymal ischemic brain tissue to evaluate the neuronal regeneration. We employed a luciferase reporter assay to identify and validate that the target gene of miR-26a-5p is PTEN. Real-time quantitative polymerase chain reaction(RT-qPCR) was used to assess gene expression levels of PTEN and miR-26a-5p and Western blot to assess the protein levels of PTEN, PI3K, p-PI3K, Akt, and p-Akt. The results revealed that compared with model group, Buyang Huanwu Decoction treatment promoted neural function recovery, reduced the cerebral infarct volume, increased the number of BrdU~+/NeuN~+ neurons, upregulated the expression of miR-26a-5p, regulated the PTEN/PI3K/Akt signaling pathway, and promoted neuronal regeneration in the cerebral ischemia-reperfusion rats. These effects were significantly enhanced after lateral ventricle injection of miR-26a-5p agomir. The findings prove that Buyang Huanwu Decoction treatment can promote neural function recovery, reduce the cerebral infarct volume, and promote neuronal regeneration in a cerebral ischemia-reperfusion rat model, which is likely to be achieved via miR-26a-5p mediated PTEN/PI3K/Akt signaling pathway.

The Role of PTEN in Chemoresistance Mediated by the HIF-1α/YY1 Axis in Pediatric Acute Lymphoblastic Leukemia.

Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. Current chemotherapy treatment regimens have improved survival rates to approximately 80%; however, resistance development remains the primary cause of treatment failure, affecting around 20% of cases. Some studies indicate that loss of the phosphatase and tensin homolog (PTEN) leads to deregulation of the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway, increasing the expression of proteins involved in chemoresistance. PTEN loss results in deregulation of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and induces hypoxia-inducible factor 1-alpha (HIF-1α) expression in various cancers. Additionally, it triggers upregulation of the Yin Yang 1 (YY1) transcription factor, leading to chemoresistance mediated by glycoprotein p-170 (Gp-170). The aim of this study was to investigate the role of the PTEN/NF-κB axis in YY1 regulation via HIF-1α and its involvement in ALL. A PTEN inhibitor was administered in RS4;11 cells, followed by the evaluation of PTEN, NF-κB, HIF-1α, YY1, and Gp-170 expression, along with chemoresistance assessment. PTEN, HIF-1α, and YY1 expression levels were assessed in the peripheral blood mononuclear cells (PBMC) from pediatric ALL patients. The results reveal that the inhibition of PTEN activity significantly increases the expression of pAkt and NF-κB, which is consistent with the increase in the expression of HIF-1α and YY1 in RS4;11 cells. In turn, this inhibition increases the expression of the glycoprotein Gp-170, affecting doxorubicin accumulation in the cells treated with the inhibitor. Samples from pediatric ALL patients exhibit PTEN expression and higher HIF-1α and YY1 expression compared to controls. PTEN/Akt/NF-κB axis plays a critical role in the regulation of YY1 through HIF-1α, and this mechanism contributes to Gp-170-mediated chemoresistance in pediatric ALL.

A biochemical assessment of apoptosis-inducing impact of Salinomycin in combination with ciprofloxacin on human leukemia KG1-a stem-like cells in the presence and absence of insulin.

Acute Myeloid Leukemia (AML) is a fast-developing invading cancer that impacts the blood and bone marrow, marked by the rapid proliferation of abnormal white blood cells. Chemotherapeutic agents, a primary treatment for AML, encounter clinical limitations such as poor solubility and low bioavailability. Previous studies have highlighted antibiotics as effective in inducing cancer cell death and potentially preventing metastasis. Besides, insulin is known to activate the PI3K/Akt pathway, often disrupted in cancers, leading to enhanced cell survival and resistance to apoptosis. In light of the above-mentioned points, we examined the anti-cancer impact of antibiotics Ciprofloxacin (CP) and Salinomycin (SAL) and their combination on KG1-a cells in the presence and absence of insulin. This was accomplished by exposing KG1-a cells to different doses of CP and SAL alone, in combination, and with or without insulin for 24-72h. Cell viability was evaluated using the MTT assay. Besides, apoptotic effects were examined using Hoechst staining and Annexin-V/PI flow cytometry. The expression levels of Bax, p53, BIRC5, Akt, PTEN, and FOXO1 were analyzed through Real-Time PCR. CP and SAL demonstrated cytotoxic and notable pro-apoptotic impact on KG1-a cells by upregulating Bax and p53 and downregulating BIRC5, leading to G0/G1 cell cycle arrest and prevention of the PI3K-Akt signaling pathway. Our findings demonstrated that combination of CP and SAL promote apoptosis in the KG1-a cell line by down-regulating BIRC5 and Akt, as well as up-regulating Bax, p53, PTEN, and FOXO1. Additionally, the findings strongly indicated that insulin effectively mitigates apoptosis by enhancing Akt expression and reducing FOXO1 and PTEN gene expression in the cells treated with CP and SAL. Our findings showed that the combined treatment of CP and SAL exhibit a strong anti-cancer effect on leukemia KG1-a cells. Moreover, it was discovered that the PI3K-Akt signaling can be a promising target in leukemia treatment particularly in hyperinsulinemia condition.

Establishment of a trastuzumab-resistant extramammary Paget disease model: loss of PTEN as a potential mechanism.

Extramammary Paget disease (EMPD) is a rare, cutaneous intraepithelial adenocarcinoma typically treated with wide local excision. Unfortunately, a number of patients with metastases show poor responses to chemotherapy. While some studies have explored trastuzumab's effectiveness against EMPD positive for human epidermal growth factor receptor 2 (HER2), trastuzumab resistance (TR) may emerge after anti-HER2 therapy. In this study, we established TR EMPD patient-derived xenografts (PDX) that replicated the histological and HER2 expression traits of naive EMPD tumours. Cancer gene analyses revealed a loss of the PTEN gene in TR tumours, which was further confirmed by immunohistochemical staining and immunoblotting to test for protein expression levels. Reduced PTEN levels correlated with increased protein kinase B (Akt) phosphorylation and p27 downregulation, suggesting a potential mechanism for trastuzumab resistance in EMPD cells. In the trastuzumab-sensitive EMPD-PDX mouse model, PTEN inhibitors partially restored trastuzumab-mediated tumour regression. The TR EMPD-PDX responded favourably to targeted therapy (lapatinib, abemaciclib, palbociclib) and chemotherapy (eribulin, docetaxel, trastuzumab deruxtecan). This study demonstrates an innovative TR EMPD-PDX model and introduces promising antineoplastic effects with various treatments for TR EMPD tumours.

Quercetin inhibits hypertonicity-induced inflammatory injury in human corneal epithelial cells via the PTEN/PI3K/AKT pathway

Dry eye is a prevalent ophthalmic disease. Ocular surface inflammation in the hyperosmolar environment of the tear film is critical in dry eye progression. Quercetin has strong anti-inflammatory effects; however, its exact mechanism of action in dry eye is not fully understood. Therefore, this study investigated whether quercetin could inhibit the damage sustained to human corneal epithelial cells (HCECs) in a hyperosmolar environment through its anti-inflammatory effects. HCECs were cultured in a complete medium and were divided into four groups: normal, model, quercetin, and inhibitor. The proliferation of HCECs was detected by Ki67 staining; the expression levels of PTEN, p-PI3K and p-AKT were detected by Western blotting and immunofluorescence staining; the relative mRNA expression levels of PTEN, PI3K, AKT, IL-6 and TNF-ɑ were detected by quantitative real-time PCR; the relative expression levels of IL-6 and TNF-α were detected by enzyme-linked immunosorbent assay. In this study, the proliferation of HCECs in the model group was found to be significantly inhibited compared with that in the normal group; however, quercetin was effective in improving the proliferation of HCECs, decreasing the relative expression of p-PI3K, p-AKT, IL-6, TNF-ɑ as well as increasing PTEN. In conclusion, this study demonstrated that quercetin could promote the proliferation of HCECs and reduce the expression of inflammatory factors by inhibiting the PTEN/PI3K/AKT pathway in the hyperosmolarity-induced HCECs model.

A black phosphorus nanosheet-based RNA delivery system for prostate cancer therapy by increasing the expression level of tumor suppressor gene PTEN via CeRNA mechanism

BackgroundProstate cancer (PCa) has a high incidence in men worldwide, and almost all PCa patients progress to the androgen-independent stage which lacks effective treatment measures. PTENP1, a long non-coding RNA, has been shown to suppress tumor growth through the rescuing of PTEN expression via a competitive endogenous RNA (ceRNA) mechanism. However, PTENP1 was limited to be applied in the treatment of PCa for the reason of rapid enzymatic degradation, poor intracellular uptake, and excessively long base sequence to be synthesized. Considering the unique advantages of artificial nanomaterials in drug loading and transport, black phosphorus (BP) nanosheet was employed as a gene-drug carrier in this study.ResultsThe sequence of PTENP1 was adopted as a template which was randomly divided into four segments with a length of about 1000 nucleotide bases to synthesize four different RNA fragments as gene drugs, and loaded onto polyethyleneimine (PEI)-modified BP nanosheets to construct BP-PEI@RNA delivery platforms. The RNAs could be effectively delivered into PC3 cells by BP-PEI nanosheets and elevating PTEN expression by competitive binding microRNAs (miRNAs) which target PTEN mRNA, ultimately exerting anti-tumor effects.ConclusionsTherefore, this study demonstrated that BP-PEI@RNAs is a promising gene therapeutic platform for PCa treatment.Graphical

Diet induced insulin resistance is due to induction of PTEN expression.

Type 2 Diabetes (T2D) is a condition that is often associated with obesity and defined by reduced sensitivity of PI3K signaling to insulin (insulin resistance), hyperinsulinemia and hyperglycemia. Molecular causes and early signaling events underlying insulin resistance are not well understood. Insulin activation of PI3K signaling causes mTOR dependent induction of PTEN translation, a negative regulator of PI3K signaling. We speculated that insulin resistance is due to insulin dependent induction of PTEN protein that prevent further increases in PI3K signaling. Here we show that in a diet induced model of obesity and insulin resistance, PTEN levels are increased in fat, muscle and liver tissues. Onset of hyperinsulinemia and PTEN induction in tissue is followed by hyperglycemia, hepatic steatosis and severe glucose intolerance. Treatment with a PTEN phosphatase inhibitor prevents and reverses these phenotypes, whereas an mTORC1 kinase inhibitor reverses all but the hepatic steatosis. These data suggest that induction of PTEN by increasing levels of insulin elevates feedback inhibition of the pathway to a point where downstream PI3K signaling is reduced and hyperglycemia ensues. PTEN induction is thus necessary for insulin resistance and the type 2 diabetes phenotype and a potential therapeutic target.

Modulation of PI3K/AKT/mTOR signaling pathway in the ovine liver and duodenum during early pregnancy

The liver and intestine play a critical role in nutrient absorption, storage, and metabolism. The aim of this study was to evaluate expression pattern of phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of the rapamycin (mTOR) signaling pathway that included PI3K, AKT1, mTOR, FoxO1, SREBP-1, PPARα, PTEN and FXR in the maternal liver and duodenum. Ovine livers and duodenums were sampled at day 16 of the estrous cycle, and at days 13, 16 and 25 of gestation, and RT-qPCR, western blot and immunohistochemistry analysis were used to detect mRNA and protein expression. The results showed that expression of PI3K, AKT1, p-mTOR, FoxO1, SREBP-1 and PTEN upregulated in the maternal liver, and PPARα upregulated in the duodenum. However, expression of FoxO1, SREBP-1 and PTEN in the duodenum downregulated during early pregnancy. In addition, expression levels of SREBP-1, PTEN and PPARα in the maternal liver, and PI3K in the duodenum peaked at day 13 of pregnancy. In addition, expression levels of PI3K, p-mTOR and FoxO1 in the liver, and AKT1 and p-mTOR in the duodenum peaked at day 16 of pregnancy. Nevertheless, expression levels of FXR both in the maternal liver duodenum downregulated at days 13 and 16 of pregnancy. In conclusion, early pregnancy regulated expression pattern of PI3K/AKT/mTOR signaling pathway in the ovine liver and duodenum in a pregnancy stage-specific and tissue-specific manner, which may be necessary for the adaptations in maternal hepatic nutrient metabolism and intestinal nutrient absorption early pregnancy.

Decorin impeded the advancement of thyroid papillary carcinoma by thwarting the EGFR/ FER/ SHP2 signaling-induced sustenance of early endosomes

ObjectiveThis study explores the inhibition of papillary thyroid carcinoma proliferation by Decorin via the EGFR/SHP2/FER pathway. Methodology: Thirty-two pairs of papillary thyroid carcinoma tissues and adjacent normal tissues were collected for immunohistochemical analysis. Thyroid cancer cell lines with overexpressed or silenced Decorin were employed in subcutaneous tumor formation experiments in nude mice. Cell membrane proteins were extracted for Western blot and immunofluorescence analyses. ResultsReduced Decorin expression in human papillary thyroid carcinoma was associated with inhibited formation of the EGFR/SHP2/FER complex. Immunohistochemical analysis revealed lower Decorin levels in carcinoma tissues compared to adjacent normal tissues, corroborated by decreased Decorin and PTEN levels in carcinoma as shown by Western Blot. Overexpression of Decorin in mouse models diminished tumor growth, an effect reversed by Decorin silencing and mitigated by FER inhibition. Decorin modulated Rab5-GTP and Rab7-GTP levels, impacting endosome transition and subsequent signaling pathways. ConclusionDecorin inhibits papillary thyroid carcinoma proliferation by disrupting the EGFR/SHP2/FER pathway and modulating endosomal transport.

Arsenic Nanoparticles Trigger Apoptosis via Anoikis Induction in OECM-1 Cells.

Arsenic compounds have been used as therapeutic alternatives for several diseases including cancer. In the following work, we obtained arsenic nanoparticles (AsNPs) produced by an anaerobic bacterium from the Salar de Ascotán, in northern Chile, and evaluated their effects on the human oral squamous carcinoma cell line OECM-1. Resazurin reduction assays were carried out on these cells using 1-100 µM of AsNPs, finding a concentration-dependent reduction in cell viability that was not observed for the non-tumoral gastric mucosa-derived cell line GES-1. To establish if these effects were associated with apoptosis induction, markers like Bcl2, Bax, and cleaved caspase 3 were analyzed via Western blot, executor caspases 3/7 via luminometry, and DNA fragmentation was analyzed by TUNEL assay, using 100 µM cisplatin as a positive control. OECM-1 cells treated with AsNPs showed an induction of both extrinsic and intrinsic apoptotic pathways, which can be explained by a significant decrease in P-Akt/Akt and P-ERK/ERK relative protein ratios, and an increase in both PTEN and p53 mRNA levels and Bit-1 relative protein levels. These results suggest a prospective mechanism of action for AsNPs that involves a potential interaction with extracellular matrix (ECM) components that reduces cell attachment and subsequently triggers anoikis, an anchorage-dependent type of apoptosis.

Ornidazole Inhibits the Angiogenesis and Migration Abilities of Non-small Cell Lung Cancer (NSCLC) via Downregulation of VEGFA/VEGFR2/NRP-1 and PI3K/AKT/mTOR Pathways.

Around the world, non-small cell lung cancer (NSCLC) is the leading cause of cancer-related deaths among all cancers. Despite advancements in new therapeutic approaches over the past few decades, the five-year survival rate still remains disappointing. The lack of effective anti-angiogenic and anti-migration drugs is the biggest obstacle to the treatment of metastatic lung cancer. Therefore, there is a need to develop new and effective therapeutic compounds targeting anti-angiogenic and anti-migration pathways for the treatment of lung cancer. Ornidazole is a nitroimidazole agent widely used in the treatment of parasitic infections such as trichomonas vaginalis, amebiasis and giardiasis. This study aimed to investigate the anti-proliferative, anti-angiogenic and anti-mitotic activities of the anti-parasitic drug Ornidazole in two human lung cancer cell lines (A549, H1299). We determined the effects of Ornidazole, on cell viability, apoptosis, migration, angiogenesis and metastatic ability against NSCLC in lung cancer cell lines. Its action on the mRNA and protein expression levels of VEGFA, VEGFR2, NRP1, Casp9, Casp3, Bax, Bcl-2, PIK3CA, AKT, MTOR, PTEN and FOX3A was assessed. Furthermore, in this study the effects on cell migration, cell viability and proliferation was evaluated through wound healing, MTT and Crystal violet assays. This study demonstrated that Ornidazole effectively reduces cell viability and migration ability, inhibits angiogenesis and metastatic abilities in NSCLC cells. In conclusion, these results may shed light on the treatment of NSCLC, and we suggest the anti-parasitic drug Ornidazole as a new agent with potential anti-angiogenic and anti-mitotic activity by interfering with the molecular pathways that trigger tumor angiogenesis and migration.

Cytotoxic and molecular differences of anticancer agents on 2D and 3D cell culture.

Cancer and multidrug resistance are regarded as concerns related to poor health outcomes. It was found that the monolayer of 2D cancer cell cultures lacks many important features compared to Multicellular Tumor Spheroids (MCTS) or 3D cell cultures which instead have the ability to mimic more closely the in vivo tumor microenvironment. This study aimed to produce 3D cell cultures from different cancer cell lines and to examine the cytotoxic activity of anticancer medications on both 2D and 3D systems, as well as to detect alterations in the expression of certain genes levels. 3D cell culture was produced using 3D microtissue molds. The cytotoxic activities of colchicine, cisplatin, doxorubicin, and paclitaxel were tested on 2D and 3D cell culture systems obtained from different cell lines (A549, H1299, MCF-7, and DU-145). IC50 values were determined by MTT assay. In addition, gene expression levels of PIK3CA, AKT1, and PTEN were evaluated by qPCR. Similar cytotoxic activities were observed on both 3D and 2D cell cultures, however, higher concentrations of anticancer medications were needed for the 3D system. For instance, paclitaxel showed an IC50 of 6.234µM and of 13.87µM on 2D and 3D H1299 cell cultures, respectively. Gene expression of PIK3CA in H1299 cells also showed a higher fold change in 3D cell culture compared to 2D system upon treatment with doxorubicin. When compared to 2D cell cultures, the behavior of cells in the 3D system showed to be more resistant to anticancer treatments. Due to their shape, growth pattern, hypoxic core features, interaction between cells, biomarkers synthesis, and resistance to treatment penetration, the MCTS have the advantage of better simulating the in vivo tumor conditions. As a result, it is reasonable to conclude that 3D cell cultures may be a more promising model than the traditional 2D system, offering a better understanding of the in vivo molecular changes in response to different potential treatments and multidrug resistance development.