HIF-1alpha Research Articles

Ginsenosides ameliorates high altitude-induced hypoxia injury in lung and kidney tissues by regulating PHD2/HIF-1α/EPO signaling pathway.

Background: The primary constituent of ginseng, known as ginsenosides (GS), has been scientifically demonstrated to possess anti-fatigue, anti-hypoxia, anti-inflammatory, and antioxidant properties. However, the effect and mechanisms of GS on tissue injury induced by high-altitude hypoxia still remain unclear. Aim of the study: This study aims to investigate the protective effect of GS on a high-altitude hypoxia model and explore its mechanism. Materials and methods: Sprague-Dawley rats were placed in a high-altitude simulation chamber for 48h (equivalent to an altitude of 6,000m) to establish a high-altitude hypoxia model. We assessed the anti-hypoxic efficacy of GS through blood gas analysis, complete blood count, and hemorheology analysis. We used H&E and hypoxia probe assays to evaluate the protective effect of GS on organ ischemia-induced injury. Further, we used ELISA and qPCR analysis to detect the levels of inflammatory factors and oxidative stress markers. Immunohistochemistry and immunofluorescence staining were performed to determinate protein expression of hypoxia inducible factor 1-alpha (HIF-1α), erythropoietin (EPO), and prolyl hydroxylase 2 (PHD2). Results: In the survival experiment of anoxic mice, 100mg/kg of GS had the best anti-anoxic effect. GS slowed down the weight loss rate of rats in hypoxic environment. In the fluorescence detection of hypoxia, GS reduced the fluorescence signal value of lung and kidney tissue and alleviated the hypoxia state of tissue. Meanwhile GS improved blood biochemical and hematological parameters. We also observed that GS treatment significantly decreased oxidative stress damage in lung and kidney tissues. Further, the levels of inflammatory factors, IL-1β, IL-6, and TNF-α were reduced by GS. Finally, GS regulated the PHD2/HIF-1α/EPO signaling pathway to improve blood viscosity and tissue hyperemia damage. Conclusion: GS could alleviate high-altitude induced lung and kidney damage by reducing the level of inflammation and oxidative stress, improving blood circulation through the PHD2/HIF-1α/EPO pathway.

Diverse responses of hypoxia-inducible factor alpha mRNA abundance in fish exposed to low oxygen: the importance of reporting methods.

Low dissolved oxygen (hypoxia) poses significant challenges to aquatic ecosystems, affecting the behavior, reproduction, and survival of aquatic organisms. Some fishes respond to hypoxia by changes in gene expression, which may be regulated by the hypoxia inducible factor (HIF) family of transcription factors. HIF abundance and activity depends upon the post-translational modification of the alpha protein subunit, although several studies indicate that HIFA mRNA abundance increases in tissues of fishes exposed to hypoxia. This study reviewed reports of laboratory exposures of adult ray-finned fishes to hypoxia and used generalized linear mixed effects models to examine the influence of HIFA gene, tissue sampled, and exposure conditions in explaining the diversity of responses seen in HIFA mRNA abundance. The frequency of hypoxia-induced increases in HIFA mRNA was poorly explained by gene, tissue, or the severity of the hypoxic exposure. Rather, the frequency of reported increases was strongly related to the extent to which studies adhered to guidelines for documenting quantitative real-time PCR methods: the frequency of hypoxia-induced increases in HIFA mRNA decreased sharply in studies with more thorough description of experimental design. Future research should (a) adhere to stringent reporting of experimental design, (b) address the relative paucity of data on HIF2A and HIF3A, and (c) determine levels of HIF alpha protein subunits. By following these recommendations, it is hoped that a more complete understanding will be gained of the role of the HIF family of transcription factors in the response of fish to hypoxia.

Unlocking the Potential of Ultra-High Dose Fractionated Radiation for Effective Treatment of Glioblastoma in Mice.

Background: Current radiotherapy regimens for glioblastoma (GBM) have limited efficacy and fails to eradicate tumors. Regenerative medicine brings hope for repairing damaged tissue, opening opportunities for elevating the maximum acceptable radiation dose. In this study, we explored the effect of ultra-high dose fractionated radiation on tumor responses and brain injury in immunocompetent mice which can better mimic the tumor-host interactions observed in patients. We also evaluated the role of the hypoxia-inducible factor-1 alpha under radiation as potential target for combating radiation-induced brain injury. Methods: Naïve and Hif-1α+/- heterozygous mice received a fractionated daily dose of 20 Gy for three or five consecutive days. Magnetic resonance imaging (MRI) and histology were performed to assess brain injury post-radiation. The 2×105 human GBM1 luciferase-expressing cells were transplanted with tolerance induction protocol. Fractionated radiotherapy was performed during the exponential phase of tumor growth. Bioluminescence imaging, MRI, and immunohistochemistry staining were performed to evaluate tumor growth dynamics and radiotherapy responses. Additionally, animal lifespan was recorded. Results: Fractionated radiation of 5×20 Gy induced severe brain damage, starting 3 weeks after radiation. All animals from this group died within 12 weeks. In contrast, later onset and less severe brain injury were observed starting 12 weeks after radiation of 3×20 Gy. It resulted in complete GBM eradication and survival of all treated animals. Furthermore, Hif-1α+/- mice exhibited more severe vascular damage after fractionated radiation of 3×20 Gy. Conclusion: Ultra-high dose fractionated 3×20 Gy radiation has the potential to fully eradicate GBM cells at the cost of only mild brain injury. The Hif-1α gene is a promising target for ameliorating vascular impairment post-radiation, encouraging the implementation of neurorestorative strategies.

Effect of Cyclophilin A on Biological Behavior of Placental Trophoblast Cells in Severe Preeclampsia by Regulating HIF-1 Alpha Signaling Pathway

Effect of Cyclophilin A on Biological Behavior of Placental Trophoblast Cells in Severe Preeclampsia by Regulating HIF-1 Alpha Signaling Pathway

Decreased Angiopoietin Expression in Underactive Bladder Induced by Long-term Bladder Outlet Obstruction.

Ischemia of the bladder can occur if neovascular formation cannot keep pace with hypoxia induced by chronic bladder outlet obstruction (BOO). The aim of this study was to examine changes in angiogenesis growth factor expression generated by chronic BOO in a rat model of underactive bladder. Twenty female Sprague-Dawley rats aged 6 weeks were assigned to 4 groups (5 rats per group). Group 1 was the control. Group 2 underwent sham surgery. The rats in groups 3 and 4 underwent BOO and were followed up for 1 week and 8 weeks. Cystometry was carried out together with bladder tissue analysis at 1 week and 8 weeks postoperatively. Real-time polymerase chain reaction (PCR) assays were conducted to determine the expression level of angiogenesis-related growth factors. A hypoxia signaling pathway PCR array was additionally carried out. The group that underwent BOO for 8 weeks showed abnormal bladder function, with a diminished intercontraction interval, decreased maximal voiding pressure, and higher volume of residual urine (P<0.05). Hypoxia-inducible factor-1 alpha expression was elevated in this group. The expression levels of vascular endothelial growth factor (VEGF) and VEGF receptor messenger RNA (mRNA) in the BOO group were comparable to those in the control group. However, angiotensin/tie receptor mRNA expression levels increased at 1 week after BOO, but decreased at 8 weeks after BOO. In animals that underwent BOO, fewer blood vessels exhibited positive immunofluorescent staining for von Willebrand factor. Alterations were also seen in the hypoxia signaling pathway PCR array. In a rat model of underactive bladder caused by surgical BOO, reduced angiopoietin expression was demonstrated. This observation might underlie visceral ischemia and fibrosis associated with the procedure. The findings of this study might offer an improved understanding of the disease processes underlying BOO and facilitate selection of the appropriate time to repair the organ in this condition.

Effect of umbilical cord mesenchymal stem cells on hypoxia-inducible factor-1 alpha (HIF-1α) production in arteriovenous fistula (AVF) animal model: A preliminary study.

Hypoxia-inducible factor-1 alpha (HIF-1α) is a transcription factor that plays a crucial role in cellular responses to hypoxia, such as in the development of intimal hyperplasia, a common complication in arteriovenous fistula (AVF) creation. While the application of umbilical cord mesenchymal stem cells (UC-MSCs) has shown promise in various regenerative medicine applications, including tissue repair and angiogenesis, the effect of UC-MSCs on HIF-1α level in the AVF has not been tested. Therefore, the aim of this study was to evaluate the effect of UC-MSCs administration on HIF-1α levels in the AVF animal model. An experimental study was conducted on 28 local male rabbits (Lepus domestica) using a post-test-only design. The rabbits were divided randomly into four groups: normal rabbit group (negative control), placebo-treated AVF rabbit group (positive control), AVF rabbits treated with in-situ UC-MSCs injection (one dose, 106 UC-MSCs/kg body weight), and AVF rabbits treated with intravenous UC-MSCs (one dose, 106 UC-MSCs/kg body weight (BW). HIF-1α level was measured using ELISA method after 28 days post-treatment. All data were analyzed using the one-way analysis of variance (ANOVA) and continued with the Duncan's post-hoc test. The data indicated that the levels of HIF-1α were different among all four groups (p<0.001). The post-hoc analysis revealed that the HIF-1α levels in both UC-MSC treated groups were significantly lower compared to untreated AVF rabbits (p<0.05). This study suggests that UC-MSCs could be a promising therapy to prevent and reduce intimal hyperplasia in AVF.

MRI-Based Assessment of Brain Tumor Hypoxia: Correlation with Histology.

Cerebral hypoxia significantly impacts the progression of brain tumors and their resistance to radiotherapy. This study employed streamlined quantitative blood-oxygen-level-dependent (sqBOLD) MRI to assess the oxygen extraction fraction (OEF)-a measure of how much oxygen is being extracted from vessels, with higher OEF values indicating hypoxia. Simultaneously, we utilized vessel size imaging (VSI) to evaluate microvascular dimensions and blood volume. A cohort of ten patients, divided between those with glioma and those with brain metastases, underwent a 3 Tesla MRI scan. We generated OEF, cerebral blood volume (CBV), and vessel size maps, which guided 3-4 targeted biopsies per patient. Subsequent histological analyses of these biopsies used hypoxia-inducible factor 1-alpha (HIF-1α) for hypoxia and CD31 for microvasculature assessment, followed by a correlation analysis between MRI and histological data. The results showed that while the sqBOLD model was generally applicable to brain tumors, it demonstrated discrepancies in some metastatic tumors, highlighting the need for model adjustments in these cases. The OEF, CBV, and vessel size maps provided insights into the tumor's hypoxic condition, showing intertumoral and intratumoral heterogeneity. A significant relationship between MRI-derived measurements and histological data was only evident in the vessel size measurements (r = 0.68, p < 0.001).

Dual Strategy with Adipose-Derived Stem Cells and l-arginine Recovered Cavernosal Functions in a Rat Model of Radical Prostatectomy.

As standard therapy for prostate cancer, radical prostatectomy causes cavernous nerve (CN) injury and increases fibrosis and hypoxia-induced penile structural alterations. This study aimed to determine the potential beneficial effects of adipose-derived stem cells (ADSCs) and l-arginine alone or in combination on the penile erection in a rat model of erectile dysfunction caused by bilateral cavernous nerve transection (CNT). Male rats (n = 35) were randomized into five groups: Sham-operated; CNT (4-weeks); CNT plus ADSCs (1 × 106 cells by intracavernosal injection); CNT plus l-arginine (4 weeks, 10 mg/kg/day, oral); and ADSCs combined with l-arginine in CNT. In vivo erectile responses and in vitro relaxant responses were measured. Western blot and immunohistochemistry analyses were used to determine the expression and localization of endothelial nitric oxide synthase, neuronal nitric oxide synthase, transforming growth factor-beta 1, hypoxia-inducible factor-1 alpha (HIF-1α), and apoptosis markers (Bax and Bcl-2). The ratio of smooth muscle to collagen and nerve regeneration were calculated using Masson's trichrome and nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase staining. The combined treatment restored diminished erectile responses, endothelium-dependent acetylcholine, and electrical field stimulation-induced relaxation of the corpus cavernosum in rats with CNT, whereas either monotherapy produced only partial improvements. All treatment regimens restored increases in the protein expression of HIF-1 and Bax in rats with CNT. The decrease in smooth muscle mass and NADPH-diaphorase-positive nerve fibers was partially ameliorated by monotherapy, whereas combined therapy led to recovery. These findings indicate that combined treatment with ADSCs and l-arginine may restore erectile function in rats with CNT by inhibiting hypoxia-induced neurotoxicity and preserving endothelium function and smooth muscle content.

Glucose Regulates Glucose Transport and Metabolism via mTOR Signaling Pathway in Bovine Placental Trophoblast Cells.

It has been confirmed that improving the energy level of the diet contributed to the greater reproductive performance and birth weight of calves in periparturient dairy cows. To investigate the effect of glucose on nutrient transport during fetal development, the bovine placental trophoblast cells (BPTCs) were cultured in media with different glucose concentrations (1, 2, 4, 8, or 16 mg/mL). Subsequently, the BPTCs were cultured in media with 1, 8 mg/mL glucose and 8 mg/mL glucose plus 100 nmol/L rapamycin (the inhibitor of mTOR pathway). Compared with the 1 mg/mL glucose, the addition of 8 mg/mL glucose stimulated cell proliferation, upregulated the mRNA abundance of the glucose transporter GLUT1 and GLUT4, and increased the activity of glucose metabolism-related enzyme glucose-6-phosphate dehydrogenease (G6PD), lactate dehydrogenase (LDHA) and phosphoglycerate kinase 1 (PGK1), as well as adenosine-triphosphate (ATP) content (p < 0.05).Furthermore, compared with the treatment of 1 mg/mL glucose, adding 8 mg/mL of glucose-upregulated gene expression in the mTOR signaling pathway, including phosphatidylinositol3-kinase (PI3K), protein kinase B (Akt), mammalian target of rapamycin (mTOR) and 70 kDa ribosomal protein S6 kinase 2 (P70S6K) (p < 0.05).The supplementation of rapamycin downregulated the gene and protein expression of the mTOR signaling pathway, including mTOR, P70S6K, EIF4E-binding protein 1 (4EBP1), hypoxia-inducible factor 1-alpha (HIF-1α) and gene expression of glucose transporter upregulated by 8 mg/mL glucose (p < 0.05). Thus, these results indicated that the addition of 8 mg/mL glucose regulated the glucose transport and metabolism in BPTCs through the mTOR signaling pathway, thereby promoting the supply of nutrients to fetus.

HIF-1 inhibitor PX-478 for cancer therapy and other fields

Hypoxia-inducible factor 1-alpha (HIF-1) is a crucial transcription factor for tumor growth and progression. PX-478, a small molecule HIF-1 inhibitor, has been extensively studied for its potential as an anti-cancer agent in preclinical studies. This paper provides an overview of the current status of PX-478 in cancer treatment, with a focus on its application in treating pancreatic ductal adenocarcinoma (PDAC), lung cancer, breast cancer, glioma, and other kinds of cancer. This article discusses the mechanisms of action, pharmacokinetics, and pharmacodynamics of PX-478, as well as the findings of preclinical and clinical studies conducted to date. The evidence suggests that PX-478 has promising potential as a therapeutic agent for various cancer types. However, further research is needed to fully comprehend the compound's potential benefits and limitations and its optimal clinical application.

IDF-11774 Induces Cell Cycle Arrest and Apoptosis by Inhibiting HIF-1α in Gastric Cancer.

Hypoxia-inducible factor-1 alpha (HIF-1α) is a regulatory factor of intracellular oxygen supersession. The expression or increased activity of HIF-1α is closely related to various human cancers. Previously, IDF-11774 was demonstrated to inhibit HSP70 chaperone activity and suppress the accumulation of HIF-1α. In this study, we aimed to determine the effects of IDF-11774 on gastric cancer cell lines. Treatment with IDF-11774 was found to markedly decrease the proliferation, migration, and invasion of the gastric cancer cell lines. Furthermore, the phosphorylation levels of extracellular signal-regulated kinase 1/2, p38, and Jun N-terminal kinase in the mitogen-activated protein kinase signaling pathways were markedly increased in a dose-dependent manner, ultimately promoting apoptosis via the induction of cell cycle arrest. Our findings indicate that HIF-1α inhibitors are potent drugs for the treatment of gastric cancer.

10247-ET-8 HHYPOXIA-TARGETING RADIOPHARMACEUTICAL 64CU-ATSM FOR PET MONITORING WITH LOCAL THERAPY IN HIGH-GRADE GLIOMA PATIENT-DERIVED XENOGRAFT MODEL

Abstract High-grade gliomas (HGGs) are highly aggressive brain cancers characterized by the presence of hypoxia within a rapidly-growing tumor mass. Due to invasion to the surrounding brain parenchyma, these tumors commonly recur locally,, and novel local approaches are required. Here, we show a positron emission tomography (PET) integrated local therapy (PETx), to target HGGs. This technique consists of a one-step local theranostic application, followed by PET monitoring, with a hypoxia-targeting radiopharmaceutical64Cu-diacetyl-bis (N4-methylthiosemicarbazone) (64Cu-ATSM). We examined the safety and therapeutic potential of 64Cu-ATSM PETx for HGG patient-derived xenograft (PDX) tumors. PDX models were recapitulated the parent tumor phenotype of high expression of HIF-1 alpha and BNIP3, biomarkers of tissue hypoxia. We confirmed that HIF-1 alpha and BNIP3 were highly upregulated under hypoxia and 64Cu-ATSM was retained with potent cytotoxic effect under hypoxic condition in vitro. We determined that determined the maximum tolerated dose (MTD) to be 3.7 MBq in mouse. PETx using the MTD dose of 64Cu-ATSM indicated high tumor penetration, distribution, and retention of 64Cu-ATSM in PDX tumors, as compared to sham-treated mice. The 64Cu-ATSM PETx promoted DNA double-strand breaks, followed by apoptosis in tumors, and extensively prolonged overall survival with tolerable systemic toxicity. These findings indicate the potential of 64Cu-ATSM PETx to induce high uptake in the hypoxic tumor microenvironment, and strong therapeutic effects in PDX models. These findings establish 64Cu-ATSM PETx as a potential novel theranostic approach to facilitate local control of HGGs.

The role and mechanism of HIF-1α-mediated glypican-3 secretion in hypoxia-induced tumor progression in hepatocellular carcinoma

ObjectiveTo explore the expression and secretion mechanism of glypican-3 (GPC3) in hepatocellular carcinoma (HCC) cells under hypoxic conditions, and its role in tumor progression. MethodsHuh7 cells with and without the knockdown of hypoxia-inducible factor 1-alpha (HIF-1α) were cultured under 1% O2 for varying durations to induce hypoxia. The expression levels of GPC3, HSP70, CD63, STX11 and SYT7 in the cytoplasm and exosomes of Huh7 cells were evaluated by western blotting and immunofluorescence. GPC3 protein expression was further measured in cells treated with GW4869 under hypoxic conditions. Huh7 cells and human umbilical vein endothelial cells (HUVECs) were cultured with the exosomes extracted from the control and GPC3-knockdown cells, the cell proliferation, migration, epithelial-mesenchymal transition (EMT), invasion, and in vitro angiogenesis were analyzed. Tumor xenografts were established to assess the role of GPC3-deficient exosomes in tumor growth. ResultsHypoxic culture conditions downregulated GPC3, STX11 and SYT7 protein levels in the Huh7 cells and upregulated GPC3 mRNA, and also increased GPC3 protein expression in the exosomes. HIF-1α knockdown, as well as treatment with GW4869, upregulated GPC3 protein in the Huh7 cells grown under 1% O2, but downregulated exosomal GPC3. Furthermore, exosomes derived from the GPC3-knockdown cells inhibited the proliferation and migration of Huh7 cells, decreased the expression of N-cadherin, vimentin, β-catenin, c-Myc and cyclin D1, and increased that of E-cadherin. Likewise, the GPC3-deficient exosomes also suppressed the invasion and tube formation ability of the HUVECs compared to that of control cells. Consistent with the in vitro results, the GPC3-deficient exosomes also repressed tumor growth in vivo. ConclusionHypoxia promoted secretion of exosomal GPC3 through the activation of HIF-1α. GPC3-deficient exosomes inhibited the proliferation, migration and EMT of HCC cells via the Wnt/β-catenin signaling pathway, and suppressed the angiogenic potential of HUVECs. This provided a novel understanding of the role of exosomal GPC3 in HCC progression.

An AMPK agonist suppresses the progress of colorectal cancer by regulating the polarization of TAM to M1 through inhibition of HIF-1α and mTOR signal pathway.

This study aimed to evaluate the impact of an adenosine monophosphate-activated protein kinase (AMPK) agonist, metformin (MET), on the antitumor effects of macrophages and to determine the underlying mechanism involved in the process. M0 macrophages were derived from phorbol-12-myristate-13-acetate-stimulated THP-1 cells. The levels of tumor necrosis factor-alpha (TNF-α) and human leukocyte antigen-DR (HLA-DR) were decreased in macrophages incubated with HCT116 cells, whereas those of arginase-1 (Arg-1), CD163, and CD206 were elevated; these effects were reversed by MET. The transfection of small interfering (si) RNA abrogated the influence of MET on the expression of the M1/M2 macrophage biomarkers. MET significantly suppressed the proliferation and migration abilities of HCT116 cells incubated with M0 macrophages; these actions were reversed by siRNA transfection against AMPK. The hypoxia-inducible factor 1-alpha (HIF-1α), phosphorylated protein kinase B (p-AKT), and phosphorylated mammalian target of rapamycin (p-mTOR) levels were reduced by the introduction of MET and promoted by siRNA transfection against AMPK. In addition, the levels of HIF-1α, p-AKT, and p-mTOR suppressed by MET were markedly increased following the transfection of siRNA against AMPK. These findings indicate that MET can repress the progression of colorectal cancer by transforming tumor-associated macrophages to the M1phenotype via inhibition of the HIF-1α and mTOR signaling pathways.

Network pharmacology integrated with molecular docking technology to reveal the potential mechanism of Shuganfang against drug-induced liver injury.

This study aimed to investigate the active composition and mechanism of the Shuganfang (SGF) in treating drug-induced liver injury (DILI) using network pharmacology and molecular docking. The potential active ingredients and targets of SGF were obtained from the Traditional Chinese Medicine Systems Pharmacology Database (TCMSP) database. DILI-related targets were queried from various databases including GEO, GeneCards, OMIM, NCBI, and DisGeNET. The STRING database was used to establish a protein-protein interaction (PPI) network. DAVID was utilized for conducting gene ontology (GO) function enrichment and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analyses. The data visualization and analysis of herb-ingredient-target and disease-pathway-target-ingredient networks were conducted using Cytoscape software (version 3.7.2). PyMoL and AutoDock software was used to select the best binding target for molecular docking. A total of 177 active ingredients,126 targets and 10112 disease targets were obtained, including 122 intersection targets. The identified potential active ingredients consisted of quercetin, kaempferol, luteolin, tanshinone IIa, nobiletin, isorhamnetin, beta-sitosterol and naringenin. The core targets implicated in the study were IL6, estrogen receptor 1 (ESR1), hypoxia-inducible factor alpha subunit 1 (HIF1A), MYC and vascular endothelial growth factor A (VEGFA). KEGG analysis revealed that the treatment of DILI with SGF mainly acted through apoptosis, the PI3K-Akt signaling pathway, and the tumor necrosis factor (TNF) signaling pathway. Furthermore, the binding affinities between the potential ingredients and the core targets were subsequently confirmed through molecular docking experiments. The findings indicated that the docking outcomes remained consistent and demonstrated a favorable capacity for binding. SGF exerts a therapeutic effect on DILI through multiple active ingredients, multiple targets and multiple pathways. Our findings contribute to a positive investigation and establish a theoretical basis for further extensive exploration of SGF as a potential treatment for DILI in future research.

Novel Risk Models and Promising Biomarkers for Prognostic Prediction in T-Cell Lymphoma with Pleural Effusion

Introduction: T-cell lymphomas (TCLs), a cluster of lymphoproliferative diseases, display high heterogeneity of characteristics, and lack for accurate prognostic models and precision treatment at present. Pleural effusion (PE) is a relatively severe manifestation of lymphomas, which has been found to be associated with worse prognosis in tumor patients, posing more challenges for risk stratification in TCL patients. Methods: Entire of 472 new diagnosed TCL patients were included from Shandong Provincial Hospital (2010-2022), and 130 among them with PE were retrospectively investigated to evaluate the prognostic value of clinical factors. The study was performed with the approval of the Medical Ethical Committee of Shandong Provincial Hospital, and all samples were collected with informed consents. RNA sequencing datasets GSE5584, GSE58445 and GSE6338 from GEO database were applied for the identification and function analysis of PE-related genes (PERGs). LASSO Cox regression analysis was utilized to reveal the prognostic role of PERGs in TCL patients. Immunohistochemistry (IHC) was applied to explore the expression and prognostic significance of HIF1A in TCLs. Results: 130 TCL patients with PE were found to display worse prognosis compared to non-PE group (P &amp;lt; 0.0001). Three clinical variables were confirmed as independently prognostic factors in TCL patients with PE, including serum albumin concentration (ALB) &amp;lt; 40 g/L (HR = 0.346, P = 0.0452), PE volume (PEV) &amp;gt; 500ml (HR = 2.192, P = 0.0269) and serum procalcitonin concentration (PCT) &amp;gt; 0.05ng/ml (HR = 3.408, P = 0.0036). After addition of these three variables to NCCN IPI, we constructed NAPP prognostic model (NAPP score = 3 × NCCN IPI - ALB + 8 × PEV + 12 × PCT) in TCL patients with PE. With an Akaike information criterion (AIC) of 363.14 and concordance index (C-index) of 0.71, NAPP prognostic model obviously improved the prediction performance of NCCN IPI (AIC = 741.01 and C-index = 0.52). Then we used the “cutoff” package in R to choose optimum marginal value, patients with NAPP risk score &amp;lt; 41 were deemed as low risk while ≥ 41 were high risk. Kaplan-Meier survival curve clarified that there was significant discrepancy of OS between the two groups (Fig. 1A, P &amp;lt; 0.0001). The 1-, 3-, and 5-year AUC values of NAPP for OS were 0.70, 0.64 and 0.64. The point estimated value of AUC at each prediction time was above 0.60 (Fig. 1A), suggesting that NAPP score had obvious superiority in predictive ability than current NCCN IPI and prognostic index for PTCL-unspecified (PIT) risk models. Subsequently, based on GSE55846, we found 50 miRNAs were differentially expressed (|log 2FC| &amp;gt; 1.5 and P &amp;lt; 0.05) between TCL patients with and without PE. Then, 239 predicted target genes of the 50 differentially expressed miRNAs were selected as PERGs based on miRTarBase and TargetScanHuman 8.0 databases. GO and KEGG analysis revealed the tight relationship between PERGs and tumor immunity. Besides, we constructed a signature including 4 PERGs (HIF1A, FERMT2, NFACT1 and COL1A1) in GSE58445. The 1-year AUC value for OS in the cohort was 0.78, indicating that PERGs signature had reliable predictive ability for OS in TCL patients. Moreover, the expression of hypoxia inducible factor-1 alpha (HIF1A) was verified to be decreased in TCL patients with PE through IHC. TCL patients with low expression of HIF1A suffered obviously inferior prognosis (Fig. 1B, P &amp;lt; 0.0001), especially in PE group. In non-PE group, there were no statistical differences of OS between the two groups based on HIF1A expression (P = 0.48). These results indicated that HIF1A might serve as a promising prognostic biomarker in TCL patients with PE. Conclusions: A novel NAPP risk model was firstly constructed and demonstrated to achieve accurate risk stratification for TCL patients with PE. PERGs, especially HIF1A, were closely related to tumor immune, and could act as molecular predictors for prognosis in TCL patients. These findings have the promising potential to facilitate the identification of high-risk population and the establishment of individualized treatment in TCL patients with PE.

Interrelation of Hypoxia-Inducible Factor-1 Alpha (HIF-1 α) and the Ratio between the Mean Corpuscular Volume/Lymphocytes (MCVL) and the Cumulative Inflammatory Index (IIC) in Ulcerative Colitis.

We intended to investigate the presence and medical application of serum hypoxia-inducible factor-1 alpha (HIF-1α) along with the already known systemic inflammatory markers and the new one's inflammatory indices, the proportion of mean corpuscular volume and lymphocytes (MCVL) and the cumulative inflammatory index (IIC), for patients with ulcerative colitis (UC). We sought to establish correlations that may be present between the serum levels of HIF-1α and these inflammatory indices, as well as their relationship with disease activity and the extent of UC, which can provide us with a more precise understanding of the evolution, prognosis, and future well-being of patients. Serum samples were collected from 46 patients diagnosed with UC and 23 controls. For our assessment of the serum levels of HIF-1α, we used the Enzyme-Linked Immunosorbent Assay (ELISA) technique. Thus, for HIF-1α we detected significantly higher values in more severe and more extensive UC. When it came to MCVL and IIC, we observed statistically significant differences between the three groups being compared (Severe, Moderate, and Mild). Our study highlighted that HIF-1α correlated much better with a disease activity score, MCVL, and IIC. With MCVL and IIC, a strong and very strong correlation had formed between them and well-known inflammation indices. By examining the ROC curves of the analyzed parameters, we recognized that TWI (accuracy of 83.70%) provides the best discrimination of patients with early forms of UC, followed by HIF-1α (73.90% accuracy), MCVL (70.90% accuracy), and PLR (70.40%). In our study, we observed that HIF-1α, MCVL, and PLR had the same sensitivity (73.33%) but HIF-1α had a much better specificity (60.87% vs. 58.70%, and 54.35%). Also, in addition to the PLR, HIF-1α and MCVL can be used as independent predictor factors in the discrimination of patients with early forms of UC.

CSIG-22. CAMKIIΓ INTERACTS WITH HIF-1Α IN AN OXYGEN-INDEPENDENT MANNER TO DRIVE PLASTICITY IN GLIOBLASTOMA

Abstract Glioblastoma (GBM) is a highly aggressive brain tumor that demonstrates treatment resistance. Hypoxia-inducible factor 1-alpha (HIF-1α) plays a crucial role in GBM progression and recurrence. While HIF-1α overexpression is correlated with poor GBM survival, clinical inhibitors have shown limited efficacy due to compensatory pathways that are not well understood. In previous studies, we discovered GBM upregulates HIF-1α after temozolomide (TMZ) through an unknown mechanism independent of physiological hypoxia. We demonstrated HIF-1α but not HIF-2α knockdown reduces the stem-like properties of GBM and enhances their sensitivity to TMZ therapy in vitro and in vivo. To elucidate the mechanism of TMZ-induced HIF-1α stabilization, we performed co-immunoprecipitation of HIF-1α followed by mass spectrometry analysis (IP-MS). Our findings revealed 99 binding partners that were significantly and uniquely upregulated after TMZ treatment compared to GBM cells cultured under normal oxygen tension (20% O2), hypoxia (1% O2), or DMSO. Among these interactions, we focused on the HIF-1α-CAMKIIγ axis for further investigation based on pathway enrichment, patient survival data, and co-expression analysis in the TCGA_GBM dataset. Co-immunoprecipitation experiments confirmed enhanced binding between HIF-1α and CAMKIIγ in different GBM patient-derived xenograft (PDX) lines while this interaction was significantly reduced in normal astrocytes. Knockdown of CAMKIIγ inhibited the transcriptional activity of HIF-1α, increased its protein turnover, and improved TMZ sensitivity compared to control cells following TMZ treatment. Additionally, the expression of stem-cell markers and neurosphere formation, which are associated with GBM aggressiveness, were attenuated in hypoxia and TMZ conditions when CAMKIIγ was absent. Our data demonstrated that the HIF-1α-CAMKIIγ axis is critical for TMZ-induction of HIF signaling and cellular plasticity.

NCOG-37. BELZUTIFAN IN ADULTS WITH VHL-ASSOCIATED CENTRAL NERVOUS SYSTEM HEMANGIOBLASTOMA: A SINGLE-CENTER EXPERIENCE

Abstract INTRODUCTION Belzutifan is a selective inhibitor of hypoxia-inducible factor 2-alpha that has been FDA approved for Von Hippel–Lindau (VHL) syndrome-associated tumors. There is limited real-world evidence in CNS hemangioblastoma. Our objective was to report on our clinical experience with belzutifan. METHODS We retrospectively reviewed our institutional (Mayo Clinic Rochester) experience of belzutifan in adults (18 years or older) with VHL and craniospinal hemangioblastomas not amenable to surgery. The study period was October 2021 to March 2023. RESULTS 4 patients (all female) with a median age of 36 years at time of belzutifan initiation were included. Median duration of therapy at last follow-up was 11 months (6-17 months). All patients had radiographic response to therapy after a median of 3 months (2-5 months), with maximal response to therapy after a median of 8 months (3-17 months). Therapy was well tolerated. The most common adverse effect was anemia. No patients had treatment pauses or dose adjustments due to toxicity. No patients experienced hypoxia. DISCUSSION We showed that belzutifan is safe and well-tolerated with strong disease response for CNS hemangioblastoma in adults with VHL, supporting continued use of belzutifan in this patient population. Future studies should assess duration of treatment, effects of cessation after long-term use, and markers of therapeutic response.

MODL-14. IMAGING, HISTOLOGICAL AND MOLECULAR CHARACTERIZATION AND COMPARISON OF POST-ABLATION RECURRENT TUMOR WITH THE PRIMARY TUMOR IN A PRECLINICAL GLIOBLASTOMA MODEL

Abstract Recurrent glioblastoma (rGBM) is highly aggressive and invasive. A reliable preclinical model that recapitulates these features is not presently available. The objective was to generate a preclinical rGBM model, characterize and compare its imaging, histological and molecular signatures in comparison to the primary tumor. Immune-suppressed, RNU/RNU female rats were implanted with U251N tumor cells in one brain hemisphere (n=33). Tumor progression in all rats was followed by longitudinal dynamic contrast enhanced-magnetic resonance imaging (DCE-MRI). In 24 rats the tumor was ablated under diffusion-weighted imaging (DWI)-guided laser interstitial thermal therapy (LITT) at post-implantation 2-weeks. Cohorts from twenty ablated rats were euthanized at post-LITT 24 h, 2- and 4-weeks and, along with 5 unablated controls, used for hematoxylin and eosin (H&amp;E) and Ki67 staining. Tissues from 4 other unablated and 4 recurrent tumors at post-LITT 2-weeks were used for RNAseq. All the rats survived the LITT procedure. Unablated controls showed increased tumor burden by post-implantation 2 weeks and were euthanized. In the LITT group, MRI showed little tumor tissue at 24 h, evidence of recurrence at 2 weeks and significant tumor tissue at 4 weeks and matched with histological evidence for tumor recurrence. Compared to the primary tumor, H&amp;E staining showed increased vascular hyperplasia, mitotic bodies and hypoxic regions with pseudopalisading necrosis in the recurrent tumor. Increased KI67 staining in recurrent tumors suggested higher rates of proliferation and evidence of infiltration into host tissue. Pathway analyses demonstrated differentially expressed genes in the canonical pathways of hypoxia-inducible factor-alpha (HIF-1α), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and OX40 signaling. The genes for the following functions were significantly affected: cell cycle, cellular movement and cell morphology. Reliable preclinical rGBM models are few. These data suggest that this model replicates the features of human rGBM and can be useful in testing putative anti-glioma therapies.