PTEN Protein Research Articles

PTEN hamartoma tumor syndrome: Clinical and genetic characterization in pediatric patients.

The aim of this study was to provide a full characterization of a cohort of 11 pediatric patients diagnosed with PTEN hamartoma tumor syndrome (PHTS). Eleven patients with genetic diagnostic of PHTS were recruited between February 2019 and April 2023. Clinical, imaging, demographic, and genetic data were retrospectively collected from their hospital medical history. Regarding clinical manifestations, macrocephaly was the leading sign, present in all patients. Frontal bossing was the most frequent dysmorphism. Neurological issues were present in most patients. Dental malformations were described for the first time, being present in 27% of the patients. Brain MRI showed anomalies in 57% of the patients. No tumoral lesions were present at the time of the study. Regarding genetics, 72% of the alterations were in the tensin-type C2 domain of PTEN protein. We identified four PTEN genetic alterations for the first time. PTEN mutations appear with a wide variety of clinical signs and symptoms, sometimes associated with phenotypes which do not fit classical clinical diagnostic criteria for PHTS. We recommend carrying out a genetic study to establish an early diagnosis in children with significant macrocephaly. This facilitates personalized monitoring and enables anticipation of potential PHTS-related complications.

The interplay of PTEN and AKT nexus in breast cancer: a molecular perspective.

Breast cancer is a highly prevalent and life-threatening ailment that is commonly detected among the females. The downregulation of PTEN in breast cancer is associated with a poor prognosis, aggressive tumor type, and metastasis to lymph nodes, as it activates the pro-survival pathway PI3K/AKT, which is considered the ultimate proliferative pathway. The mRNA expression of PTEN and AKT genes was investigated using RT-qPCR and TaqMan primer probe chemistry. Moreover DNA was also isolated from the same tissue samples and exonic regions of both genes were amplified for mutational analysis. The proteins expression of PTEN and AKT from seven human breast cancer cell lines was checked through western blot experiments. The study revealed a decrease in PTEN expression in 73.3% of the samples, whereas an increase in AKT expression in 40% of samples was observed when compared to the distant normal breast tissue. Conversely, the remaining 60% of samples exhibited a decrease in AKT mRNA expression. There was no observed alteration in the genetic sequence of AKT and PTEN within the targeted amplified regions ofbreast cancer samples. The high levels of PTEN protein in T-47D and MDA-MB-453 resulted in a lower p-AKT. Two cell lines ZR-75-1 and MDA-MB-468 appeared to be PTEN negative on western blot but mRNA was detected on RT-qPCR. In breast cancer the status/expression of PTEN & AKT at mRNA and protein level might be obliging in forecasting the path of disease progression, treatment and prognosis.

Capivasertib combines with docetaxel to enhance anti-tumour activity through inhibition of AKT-mediated survival mechanisms in prostate cancer

Background/objectiveTo explore the anti-tumour activity of combining AKT inhibition and docetaxel in PTEN protein null and WT prostate tumours.MethodsMechanisms associated with docetaxel capivasertib treatment activity in prostate cancer were examined using a panel of in vivo tumour models and cell lines.ResultsCombining docetaxel and capivasertib had increased activity in PTEN null and WT prostate tumour models in vivo. In vitro short-term docetaxel treatment caused cell cycle arrest in the majority of cells. However, a sub-population of docetaxel-persister cells did not undergo G2/M arrest but upregulated phosphorylation of PI3K/AKT pathway effectors GSK3β, p70S6K, 4E-BP1, but to a lesser extent AKT. In vivo acute docetaxel treatment induced p70S6K and 4E-BP1 phosphorylation. Treating PTEN null and WT docetaxel-persister cells with capivasertib reduced PI3K/AKT pathway activation and cell cycle progression. In vitro and in vivo it reduced proliferation and increased apoptosis or DNA damage though effects were more marked in PTEN null cells. Docetaxel-persister cells were partly reliant on GSK3β as a GSK3β inhibitor AZD2858 reversed capivasertib-induced apoptosis and DNA damage.ConclusionCapivasertib can enhance anti-tumour effects of docetaxel by targeting residual docetaxel-persister cells, independent of PTEN status, to induce apoptosis and DNA damage in part through GSK3β.

Tumorigenesis of basal muscle invasive bladder cancer was mediated by PTEN protein degradation resulting from SNHG1 upregulation

BackgroundPhosphatase and tensin homolog deleted on chromosome ten (PTEN) serves as a powerful tumor suppressor, and has been found to be downregulated in human bladder cancer (BC) tissues. Despite this observation, the mechanisms contributing to PTEN’s downregulation have remained elusive.MethodsWe established targeted genes’ knockdown or overexpressed cell lines to explore the mechanism how it drove the malignant transformation of urothelial cells or promoted anchorageindependent growth of human basal muscle invasive BC (BMIBC) cells. The mice model was used to validate the conclusion in vivo. The important findings were also extended to human studies.ResultsIn this study, we discovered that mice exposed to N-butyl-N-(4-hydroxybu-tyl)nitrosamine (BBN), a specific bladder chemical carcinogen, exhibited primary BMIBC accompanied by a pronounced reduction in PTEN protein expression in vivo. Utilizing a lncRNA deep sequencing high-throughput platform, along with gain- and loss-of-function analyses, we identified small nucleolar RNA host gene 1 (SNHG1) as a critical lncRNA that might drive the formation of primary BMIBCs in BBN-treated mice. Cell culture results further demonstrated that BBN exposure significantly induced SNHG1 in normal human bladder urothelial cell UROtsa. Notably, the ectopic expression of SNHG1 alone was sufficient to induce malignant transformation in human urothelial cells, while SNHG1 knockdown effectively inhibited anchorage-independent growth of human BMIBCs. Our detailed investigation revealed that SNHG1 overexpression led to PTEN protein degradation through its direct interaction with HUR. This interaction reduced HUR binding to ubiquitin-specific peptidase 8 (USP8) mRNA, causing degradation of USP8 mRNA and a subsequent decrease in USP8 protein expression. The downregulation of USP8, in turn, increased PTEN polyubiquitination and degradation, culminating in cell malignant transformation and BMIBC anchorageindependent growth. In vivo studies confirmed the downregulation of PTEN and USP8, as well as their positive correlations in both BBN-treated mouse bladder urothelium and tumor tissues of bladder cancer in nude mice.ConclusionsOur findings, for the first time, demonstrate that overexpressed SNHG1 competes with USP8 for binding to HUR. This competition attenuates USP8 mRNA stability and protein expression, leading to PTEN protein degradation, consequently, this process drives urothelial cell malignant transformation and fosters BMIBC growth and primary BMIBC formation.

Zuogui Pill Promotes Neurite Outgrowth by Regulating OPN/ IGF-1R/PTEN and Downstream mTOR Signaling Pathway.

Zuogui pill (ZGP) is the traditional Chinese medicine for tonifying kidney yin. Clinical and animal studies have shown that ZGP effectively enhances neurologic impairment after ischemic stroke, which may be related to promoting neurite outgrowth. This investigation aimed to prove the pro-neurite outgrowth impact of ZGP and define the underlying molecular pathway in vitro. The major biochemical components in the ZGP were investigated using UPLC-QTOF-MS. All-trans retinoic acid (ATRA) was employed to stimulate SH-SY5Y cells to develop into mature neurons, followed by oxygen-glucose deprivation and reoxygenation damage (OGD/R). Then the cells were supplemented with different concentrations of ZGP, and cell viability was identified by CCK-8. The neurites' outgrowth abilities were detected by wound healing test, while immunofluorescence staining of β-III-tubulin was used to label neurites and measure their length. Western blot was employed to discover the changes in protein levels. ZGP improved the cell viability of differentiated SH-SY5Y cells following OGD/R damage, according to the CCK-8 assay. Concurrently, ZGP promoted neurite outgrowth and improved neurite crossing and migration ability. Protein expression analysis showed that ZGP upregulated the expression of GAP43, OPN, p-IGF-1R, mTOR, and p-S6 proteins but downregulated the expression of PTEN protein. Blocking assay with IGF-1R specific inhibitor Linstinib suggested IGF-1R mediated mTOR signaling pathway was involved in the pro-neurite outgrowth effect of ZGP. This work illustrated the molecular mechanism underpinning ZGP's action and offered more proof of its ability to promote neurite outgrowth and regeneration following ischemic stroke.

Uncovering the Mechanisms of Cinnamic Acid Treating Diabetic Nephropathy Based on Network Pharmacology, Molecular Docking, and Experimental Validation.

Cinnamic acid (Cinn) is a phenolic acid of Cinnamomum cassia (L.) J. Presl. that can ameliorate diabetic nephropathy (DN). However, comprehensive therapeutic targets and underlying mechanisms for Cinn against DN are limited. In this study, a network pharmacology approach and in vivo experiments were adopted to predict the pharmacological effects and mechanisms of Cinn in DN therapy. The nephroprotective effect of Cinn on DN was investigated by a streptozotocininduced diabetes mellitus (DM) mouse model. The protein-protein interaction network of Cinn against DN was established by a network pharmacology approach. The core targets were then identified and subjected to molecular docking with Cinn. Cinn treatment effectively restored body weight, ameliorated hyperglycemia, and reduced kidney dysfunction markers in DM mice, also demonstrating a reduction in tissue injury. Network pharmacology analysis identified 298 DN-Cinn co-target genes involved in various biological processes and pathways. Seventeen core targets were identified, eight of which showed significant differential expression in the DN and healthy control groups. Molecular docking analysis revealed a strong interaction between Cinn and PTEN. Cinn treatment downregulated the PTEN protein expression in DM mice. This study revealed the multi-target and multi-pathway characteristics of Cinn against DN. Cinn improved renal pathological damage of DN, which was related to the downregulation of PTEN.

N-Acetylcysteine Alters Disease Progression and Increases Janus Kinase Mutation Frequency in a Mouse Model of Precursor B-Cell Acute Lymphoblastic Leukemia.

B-cell acute lymphoblastic leukemia (B-ALL) is the most prevalent type of cancer in young children and is associated with high levels of reactive oxygen species (ROS). The antioxidant N-acetylcysteine (NAC) was tested for its ability to alter disease progression in a mouse model of B-ALL. Mb1-CreΔPB mice have deletions in genes encoding PU.1 and Spi-B in B cells and develop B-ALL at 100% incidence. Treatment of Mb1-CreΔPB mice with NAC in drinking water significantly reduced the frequency of CD19+ pre-B-ALL cells infiltrating the thymus at 11 weeks of age. However, treatment with NAC did not reduce leukemia progression or increase survival by a median 16 weeks of age. NAC significantly altered gene expression in leukemias in treated mice. Mice treated with NAC had increased frequencies of activating mutations in genes encoding Janus kinases 1 and 3. In particular, frequencies of Jak3 R653H mutations were increased in mice treated with NAC compared with control drinking water. NAC opposed oxidization of PTEN protein ROS in cultured leukemia cells. These results show that NAC alters leukemia progression in this mouse model, ultimately selecting for leukemias with high Jak3 R653H mutation frequencies. SIGNIFICANCE STATEMENT: In a mouse model of precursor B-cell acute lymphoblastic leukemia associated with high levels of reactive oxygen species, treatment with N-acetylcysteine did not delay disease progression but instead selected for leukemic clones with activating R653H mutations in Janus kinase 3.

Resveratrol Inhibits T-acute Lymphoblastic Leukemia in Mice by Regulating Notch1 Signaling Pathway

To observe the effect of resveratrol (Res) on T-acute lymphoblastic leukemia (T-ALL) mice, and further explore its mechanism on Notch1 signaling pathway. Twenty-five 6-8 weeks old female C57BL/6 mice were randomly divided into control group, T-ALL group and Res group. Res group was further divided into low-Res, middle-Res and high-Res group. The percentage of leukemia cells in peripheral blood and spleen cell suspension were detected by flow cytometry and Wright-Giemsa staining, pathological morphology of spleen and bone marrow tissues were observed by HE staining, the expression levels of Notch1, Hes-1, c-Myc, miR-19b and PTEN mRNA in spleen tissue were detected by RT-qPCR, and the protein levels of Notch1, Hes-1, c-Myc, p-PTEN and PTEN were detected by Western blot. Compared with control group, the leukemia cells in peripheral blood of mice in T-ALL group were markedly increased, accompanied by diffuse infiltration of leukemia cells in spleen and bone marrow tissues, the mRNA levels of Notch1, Hes-1, c-Myc, miR-19b and the protein levels of Notch1, Hes-1, c-Myc were increased (P <0.01), while the expression of PTEN mRNA and protein were significantly decreased in the spleen tissue of T-ALL mice (P <0.01). The above indicators in the H-Res group were reversed compared with T-ALL group after administration of resveratrol. Resveratrol may play a role in anti T-ALL by inhibiting Notch1 signaling pathway in mice.

Genetic and molecular backgrounds of the development of glioblastoma

Stage IV glioblastoma is the most frequently diagnosed and the worst prognosis tumor of the central nervous system (CNS). Patients suffering from this type of cancer usually survive several months with the use of surgical treatment, radiotherapy and chemotherapy. The development of glioblastoma is determined by a number of mutations, the most common of which are the p16, p19, p53, pRB, PTEN, PDGFR, CDK4 and EGFR protein genes as well as the loss of heterozygosity on chromosomes 10, 17 and 19. The occurrence of mutations within the IDH1 and IDH2 genes and increased methylation of MGMT promoter improves patient survival, but few patients live more than 3 years after diagnosis. The most important cell signaling pathways in glioblastoma are PI3K/Akt/mTOR and Wnt/β-catenin, which play a key role in tumor cell function. However, these cells are highly resistant to anticancer drugs, including inhibitors of cell signaling pathways. Currently, the potential methods of effectively combating malignant gliomas are alternating electric field therapy and the implementation of new immunotherapeutic strategies.

CHIP suppresses the proliferation and migration of A549 cells by mediating the ubiquitination of eIF2α and upregulation of tumor suppressor RBM5

The PERK-eIF2α pathway plays an essential role in endoplasmic reticulum (ER) stress. When the PERK-eIF2α pathway is activated, PERK phosphorylates eIF2α (p-eIF2α) at Ser51 and quenches global protein synthesis. In this study, we verified eIF2α as a bona fide substrate of the E3 ubiquitin ligase CHIP both in vitro and in cells. CHIP mediated the ubiquitination and degradation of nonphosphorylated eIF2α in a chaperone-independent manner and promoted the upregulation of the transcription factor ATF4 under ER stress conditions. ATF4 induced the transcriptional enhancement of the tumor suppressor genes PTEN and RBM5. Although transcription was enhanced, the PTEN protein was subsequently degraded by CHIP, but the expression of the RBM5 protein was upregulated, thereby suppressing the proliferation and migration of A549 cells. Overall, our study established a new mechanism that deepened the understanding of the PERK-eIF2α pathway through the ubiquitination and degradation of eIF2α. The crosstalk between the phosphorylation and ubiquitination of eIF2α shed light on a new perspective for tumor progression.

Pten knockout in mouse preosteoblasts leads to changes in bone turnover and strength.

Bone development and remodeling are controlled by the phosphoinositide-3-kinase (Pi3k) signaling pathway. We investigated the effects of downregulation of phosphatase and tensin homolog (Pten), a negative regulator of Pi3k signaling, in a mouse model of Pten deficiency in preosteoblasts. We aimed to identify mechanisms that are involved in the regulation of bone turnover and are linked to bone disorders. Femora, tibiae, and bone marrow stromal cells (BMSCs) isolated from mice with a conditional deletion of Pten (Pten cKO) in Osterix/Sp7-expressing osteoprogenitor cells were compared to Cre-negative controls. Bone phenotyping was performed by μCT measurements, bone histomorphometry, quantification of bone turnover markers CTX and procollagen type 1N propeptide (P1NP), and three-point bending test. Proliferation of BMSCs was measured by counting nuclei and Ki-67-stained cells. In vitro, osteogenic differentiation capacity was determined by ALP staining, as well as by detecting gene expression of osteogenic markers. BMSCs from Pten cKO mice were functionally different from control BMSCs. Osteogenic markers were increased in BMSCs derived from Pten cKO mice, while Pten protein expression was lower and Akt phosphorylation was increased. We detected a higher trabecular bone volume and an altered cortical bone morphology in Pten cKO bones with a progressive decrease in bone and tissue mineral density. Pten cKO bones displayed fewer osteoclasts and more osteoblasts (P = .00095) per trabecular bone surface and a higher trabecular bone formation rate. Biomechanical analysis revealed a significantly higher bone strength (P = .00012 for males) and elasticity of Pten cKO femora. On the cellular level, both proliferation and osteogenic differentiation capacity of Pten cKO BMSCs were significantly increased compared to controls. Our findings suggest that Pten knockout in osteoprogenitor cells increases bone stability and elasticity by increasing trabecular bone mass and leads to increased proliferation and osteogenic differentiation of BMSCs.

Levosimendan Ameliorates Hypoxia-Induced Brain Injury in Rats by Modulating PTEN/Akt Signaling Pathway-Mediated Ferroptosis.

Levosimendan (Levo) is a drug commonly used to treat heart failure. Recent studies have suggested that Levo may have neuroprotective effects, but it is still unknown how exactly it contributes to hypoxia-induced brain damage. Thus, the aim of this study was to investigate how Levo affects hypoxia-induced brain damage and to clarify any possible underlying mechanisms. One group of rats (Levo group) was pretreated with Levo via oral force-feeding for four weeks. Another group (Ferrostatin-1 (Fer-1) group) was pretreated with intraperitoneal injections of Fer-1 for four weeks. A rat model of chronic hypoxia was created by treating rats with 13% O2 for 14 days in a closed hypoxia chamber. For each group (Control, Model, Levo, Fer-1), we evaluated learning and memory capacity and the morphology and structure of neurons in the rats' brain tissue. Other measurements included tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6); malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px); Fe2+; apoptosis; cleaved caspase-3, caspase-3; phosphatase and tensin homolog (PTEN), protein kinase B (Akt), phosphorylated Akt (p-Akt); and ferroptosis-related proteins Nuclear factor erythroid 2-related factor 2 (Nrf2), glutathione peroxidase 4 (GPX4), and solute carrier family 7 member 11 (SLC7A11). The Model group rats had considerably fewer neurons than the Control group, with loosely arranged cells, and markedly impaired learning and memory abilities (p < 0.05). Oxidative damage and inflammation in brain tissues of the Model group were significantly intensified, accompanied by a substantial increase in neuronal apoptosis (p < 0.05). PTEN protein, Fe2+ concentration, and cleaved caspase-3 expression were all significantly upregulated, whereas p-Akt, Nrf2, GPX4, and SLC7A11 proteins were dramatically downregulated (p < 0.05). Both the Levo and Fer-1 groups demonstrated significantly more neurons and closely arranged cells than the Model group, along with a notable improvement in learning and memory abilities (p < 0.05). Oxidative damage and inflammation in brain tissues of the Levo and Fer-1 groups were markedly alleviated, and neuronal apoptosis was suppressed (p < 0.05). p-Akt, Nrf2, GPX4, and SLC7A11 proteins were dramatically upregulated, whereas the expression of cleaved caspase-3, PTEN protein, and Fe2+ content was considerably downregulated (p < 0.05). Levo effectively mitigates brain injury in rats with chronic hypoxia, likely by regulating ferroptosis via the PTEN/Akt signaling pathway.

Investigating the effects of PTEN mutations on cGAS-STING pathway in glioblastoma tumours

BackgroundPTEN is a tumour suppressor gene and well-known for being frequently mutated in several cancer types. Loss of immunogenicity can also be attributed to PTEN loss, because of its role in establishing the tumour microenvironment. Therefore, this study aimed to represent the link between PTEN and cGAS-STING activity, a key mediator of inflammation, in tumour samples of glioblastoma patients.MethodsTumour samples of 36 glioblastoma patients were collected. After DNA isolation, all coding regions of PTEN were sequenced and analysed. PTEN expression status was also evaluated by qRT-PCR, western blot, and immunohistochemical methods. Interferon-stimulated gene expressions, cGAMP activity, CD8 infiltration, and Granzyme B expression levels were determined especially for the evaluation of cGAS-STING activity and immunogenicity.ResultsMutant PTEN patients had significantly lower PTEN expression, both at mRNA and protein levels. Decreased STING, IRF3, NF-KB1, and RELA mRNA expressions were also found in patients with mutant PTEN. Immunohistochemistry staining of PTEN displayed expressional loss in 38.1% of the patients. Besides, patients with PTEN loss had considerably lower amounts of IFNB and IFIT2 mRNA expressions. Furthermore, CD8 infiltration, cGAMP, and Granzyme B levels were reduced in the PTEN loss group.ConclusionThis study reveals the immunosuppressive effects of PTEN loss in glioblastoma tumours via the cGAS-STING pathway. Therefore, determining the PTEN status in tumours is of great importance, like in situations when considering the treatment of glioblastoma patients with immunotherapeutic agents.

A study on molecular mechanism of Xihuang pill in the treatment of glioblastoma based on network pharmacology and validation in vitro and in vivo

Ethnopharmacological relevanceXihuang pill has been utilized to treat cancer for more than three hundred years in China. The molecular mechanisms of Xihuang pill in treating glioblastoma remains unclear. Aim of the studyThis study aimed to explore the core molecular mechanisms of Xihuang pill in treating glioblastoma by an integrative pharmacology-based investigation. Materials and methodsThe main active compounds of Xihuang pill were identified from TCMSP, BATMAN-TCM, TCMID and CNKI. Glioblastoma-related therapeutic targets were retrieved from GeneCards and UniProt. Subsequently, a protein-protein interaction (PPI) network analysis was constructed using STRING. GO and KEGG enrichment were performed to analyze the intersection targets between the active compounds of Xihuang pill and glioblastoma. Based on the above analysis, we built a CTP network. The in vitro and in vivo experiments were further performed to validate the crucial molecular targets of Xihuang pill for the treatment of glioblastoma. ResultsA total of sixty active compounds of Xihuang pill and ten potential targets related to glioblastoma were found. Based on topological analysis, fourteen ingredients were selected as the main active compounds, and MY11 might be the most important metabolite in Xihuang pill. PI3K/Akt signaling pathway and receptor tyrosine kinases were considered as crucial targets for Xihuang pill against glioblastoma through KEGG enrichment and CTP analysis. The present experiments indicated that Xihuang pill suppressed the activation of PI3K/Akt/mTOR signaling pathway in glioblastoma cells and mouse xenografts via modulating the expression of PTEN and Rheb proteins, the interaction between TSC2 and Rheb, and the production of PIP3. Meanwhile, after glioblastoma cells treatment with Xihuang pil, the release of IL-1β, INF-γ was increased and the production of IL-10, TGF-β1 was decreased in glioblastoma cells after incubated with Xihuang pill. In addition, the activation of the upstream positive modulators of PI3K/Akt/mTOR pathway including PDGF/PDGFR and FGF/FGFR signaling were down-regulated in glioblastoma cells and mouse xenografts after treatment with Xihuang pill. ConclusionTaken together, Xihuang pill inhibiting glioblastoma cell growth might be partly through down-regulating the activation of PDGF/PDGFR or FGF/FGFR-PI3K/Akt/mTOR signaling axis and improving immuno-suppressive micro-environment of glioblastoma.

The use of L-asparaginase for the treatment of solid tumors: data from experimental studies and clinical trials

Drug therapy is one of the main strategies of cancer treatment. L-asparaginase, the enzyme that hydrolyzes asparagine, has been included in the treatment regimens for acute lymphoblastic leukemia and other hematological malignancies since more than 50 years ago, but its use for the treatment of solid tumors is still extremely limited. This review analyzes experimental data on the sensitivity of cell lines and xenografts of solid tumors to L-asparaginase, examines the results of clinical trials. Among the mechanisms of the cytotoxic effect of L-asparaginase on tumor cells, such processes as depletion of aspartic and glutamic acids, influence on the internal and external pathways of apoptosis, inhibition of cellular processes through a decrease in the activity of the mTOR protein, and weakening of the expression of the telomerase gene are discussed. Separately, molecular markers are considered, which can be used to suggest the effectiveness of future therapy with L-asparaginase in solid tumors. These markers include expression levels of asparagine synthetase and glutamine synthetase genes, degree of methylation of the ASNS gene promoter region, PTEN protein activity and autophagy, bone marrow environment of tumor cells, as well as expression of genes associated with asparaginase resistance (such as the μ1 opioid receptor gene and the huntingtin-associated protein 1 gene).

The Correlations between the Intensity of Histopathological Ubiquitin-Specific Protease 11 Staining and Progression of Prostate Cancer.

Ubiquitin-specific protease 11 (USP11), one of the principal phosphatase and tensin homolog (PTEN) deubiquitinases, can reserve PTEN polyubiquitination to maintain PTEN protein integrity and inhibit PI3K/AKT pathway activation. The aim of the current study was to investigate the associations between immunohistochemical USP11 staining intensities and prognostic indicators in individuals with prostate cancer. Tissue microarrays (TMAs) were performed for human prostate cancer and normal tissue (control) samples. Data on patient's age, Gleason score, plasma prostate-specific antigen (PSA) titer, disease stage, and presence of seminal vesicles, lymph nodes, and surgical margin involvement were collected. A pathologist who was blinded to the clinical outcome data scored the TMA for USP11 staining intensity as either positive or negative. Cancerous tissues exhibited lower USP11 staining intensity, whereas the neighboring benign peri-tumoral tissues showed higher USP11 staining intensity. The degree of USP11 staining intensity was lower in patients with a higher PSA titer, higher Gleason score, or more advanced disease stage. Patients who showed positive USP11 staining were more likely to have more optimal clinical and biochemical recurrence-free survival statistics. USP11 staining intensity in patients with prostate cancer is negatively associated with several prognostic factors such as an elevated PSA titer and a high Gleason score. It also reflects both biochemical and clinical recurrence-free survival in such patients. Thus, USP11 staining is a valuable prognostic factor in patients with prostate cancer.

WITHDRAWN: CircBUB1 activates the PI3K/AKT signaling pathway to promote the migration and invasion of glioblastoma cells

BackgroundGlioblastoma (GBM) is the most aggressive primary brain tumor, characterized by rapid growth and resistance to treatment, leading to poor survival rates. The molecular mechanisms underlying GBM progression remain unclear, necessitating further research. This study focuses on the role of circBUB1, a circular RNA, in GBM cell migration and invasion, and the associated molecular mechanisms. MethodsRNA/protein expression was detected using RT-qPCR/western blot assay. Transwell and wound healing assays were conducted to assess GBM cell migration and invasion. Detailed mechanistic analyses were carried out to understand the role of circBUB1 in GBM cells. ResultsCircBUB1 was found to be highly expressed and functioned as an oncogene in GBM cells. Functional assays revealed that knockdown of circBUB1 suppressed the migration and invasion of GBM cells. Mechanistic analyses showed that circBUB1 sequestered miR-1296-5p, thereby elevating TRIM14 expression. TRIM14 was also found to promote PTEN ubiquitination, ultimately leading to the down-regulation of PTEN protein and activation of the PI3K/AKT signaling pathway. Through rescue assays, this study confirmed that circBUB1 promoted GBM cell migration and invasion by reducing PTEN protein levels. ConclusionOur findings indicate that circBUB1 activates the PI3K/AKT signaling pathway, promoting the migration and invasion of GBM cells via the miR-1296-5p/TRIM14 axis. This provides new insights into the molecular mechanisms of GBM progression and potential therapeutic targets.

Quercetin Inhibits Proliferation and Migration via miR-301b-3p/Phosphatase and Tensin Homolog Axis Regulation in Laryngocarcinoma Cells

In this study, we investigated the role of miR-301b-3p in promoting tumor cell proliferation and metastasis and explored the anti-cancer effects of quercetin in laryngocarcinoma cells. Through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation analyses, we examined the effects of miR-301b-3p and PTEN on potential target genes. We measured laryngocarcinoma cell activity and apoptosis using CCK8 and flow cytometry, respectively, and assessed migration and invasion through transwell assay. qRT-PCR was used to determine the levels of miR-301b-3p and PTEN in laryngocarcinoma cells. Luciferase activity and western blot assays were employed to study the interaction between miR-301b-3p and PTEN. We found that miR-301b-3p was associated with various types of cancer, and pathways related to miR-301b-3p overlapped with those of PTEN. Quercetin effectively inhibited the proliferation, migration, and invasion of laryngocarcinoma cells, but these effects were reversed by miR-301b-3p overexpression. The level of miR-301b-3p was significantly increased in laryngocarcinoma cells, leading to down-regulation of PTEN protein and enhanced tumor cell activity. However, restoring PTEN alleviated the malignant growth caused by miR-301b-3p overexpression. Ultimately, quercetin exerted its inhibitory effects on proliferation, migration, and invasion by regulating the miR-301b-3p/PTEN axis in laryngocarcinoma cells. These findings highlight the potential of quercetin as a promising treatment option for laryngocarcinoma.

Site-specific protein conjugates incorporating Para-Azido-L-Phenylalanine for cellular and in vivo imaging.

This work features the use of amber suppression-mediated unnatural amino acid (UAA) incorporation into proteins for various imaging purposes. The site-specific incorporation of the UAA, p-azido-L-phenylalanine (pAzF), provides an azide handle that can be used to complete the strain promoted azide-alkyne click cycloaddition (SPAAC) reaction to introduce an imaging modality such as a fluorophore or a positron emission tomography (PET) tracer on the protein of interest (POI). Such methodology can be pursued directly in mammalian cell lines or on proteins expressed in vitro, thereby conferring a homogeneous pool of protein conjugates. A general procedure for UAA incorporation to use with a site-specific protein labeling method is provided allowing for in vitro and in vivo imaging applications based on the representative proteins PTEN and PD-L1. This approach would help elucidate the cellular or in vivo biological activities of the POI.

Nicotinamide Adenine Dinucleotide Phosphate Oxidase Promotes Glioblastoma Radiation Resistance in a Phosphate and Tensin Homolog-Dependent Manner.

Aims: The goal of this study was to determine whether nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX)-produced reactive oxygen species (ROS) enhance brain tumor growth of glioblastoma (GBM) under hypoxic conditions and during radiation treatment. Results: Exogenous ROS promoted brain tumor growth in gliomasphere cultures that expressed functional phosphate and tensin homolog (PTEN), but not in tumors that were PTEN deficient. Hypoxia induced the production of endogenous cytoplasmic ROS and tumor cell growth via activation of NOX. NOX activation resulted in oxidation of PTEN and downstream protein kinase B (Akt) activation. Radiation also promoted ROS production via NOX, which, in turn, resulted in cellular protection that could be abrogated by knockdown of the key NOX component, p22. Knockdown of p22 also inhibited tumor growth and enhanced the efficacy of radiation in PTEN-expressing GBM cells. Innovation: While other studies have implicated NOX function in GBM models, this study demonstrates NOX activation and function under physiological hypoxia and following radiation in GBM, two conditions that are seen in patients. NOX plays an important role in a PTEN-expressing GBM model system, but not in PTEN-nonfunctional systems, and provides a potential, patient-specific therapeutic opportunity. Conclusion: This study provides a strong basis for pursuing NOX inhibition in PTEN-expressing GBM cells as a possible adjunct to radiation therapy. Antioxid. Redox Signal. 39, 890-903.