IGF-1R Levels Research Articles

Screening and identification of potential target of 1′-acetoxychavicol acetate (ACA) in acquired lapatinib-resistant breast cancer

1′-Acetoxychavicol acetate (ACA) eliminates breast cancer cells via the HER2/MAPK/ERK1/2 and PI3K/AKT pathways, and it also directly influences endocrine resistance by both enhancing pro-apoptotic signals and suppressing pro-survival molecules. This study utilized bioinformatics to assess ACA target genes for lapatinib-resistant breast cancer. We identified differentially expressed genes (DEGs) using GSE16179 microarray data. DEGs from ACA-treated and lapatinib-resistant cells were analyses using Panther DB, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses, and protein-protein interaction (PPI) network analysis. Genomic mutations, expression levels, prognostic significance, and ROC analysis were examined in selected genes. We used AutoDock Vina to conduct ACA molecular docking with potential target genes. In the PPI network analysis, BCL2, CXCR2, and CDC42 were the three highest-scoring genes. Genetic modification analysis identified PLAU and SSTR3 as the genes most frequently altered in breast cancer samples. The RTK-Ras pathway is likely to be affected by changes in BCL2, CXCR2, CDC42, SSTR3, PLAU, ICAM1, IGF1R, and MET genes. Patients with breast cancer who had lower levels of BCL2, SSTR3, PLAU, ICAM1, IGF1R, and MET had worse overall survival compared to other groups. ACA exhibited moderate binding affinity to BCL2, SSTR3, PLAU, ICAM1, IGF1R, and MET. Overall, ACA might counteract breast cancer resistance to lapatinib by targeting BCL2, SSTR3, PLAU, ICAM1, IGF1R, and MET. Further in vitro studies involving gene silencing could provide more detailed insights into the mechanism by which ACA combats lapatinib resistance.

Therapeutic Potential of Growth Hormone in Peripheral Nerve Injury: Enhancing Schwann Cell Proliferation and Migration Through IGF-1R-AKT and ERK Signaling Pathways.

Peripheral nerve injury (PNI) represents a prevalent condition characterized by the demyelination of affected nerves. The challenge of remyelinating these nerves and achieving satisfactory functional recovery has long been a persistent issue. The specific contributions of growth hormone (GH) in the aftermath of PNI have remained ambiguous. Our investigations have demonstrated that GH not only enhances neurological function scores but also promotes remyelination within a three-week period. Further invivo studies corroborated that GH facilitates nerve function improvement by mitigating neuronal apoptosis. Invitro, the ideal concentration of GH for exerting effects on Schwann cells (SCs) has been identified as 80 ng/mL. Subsequent research uncovered GH's profound impact on SCs proliferation, cell cycle progression, and migration. Through RNA sequencing and additional experiments, it was discovered that GH treatment elevates the phosphorylation levels of IGF-1R, AKT, and ERK. Moreover, the GH-induced proliferation and migration of SCs were significantly diminished by the inhibition of the IGF-1R pathway, achieved through pre-treatment with Linsitinib. The outcomes of this investigation suggest that GH can significantly enhance the proliferation and migration of SCs, presenting it as a viable option for PNI repair.

CDR1as/miR-7-5p/IGF1R axis contributes to the suppression of cell viability in prostate cancer

Abstract Background Prostate cancer is the most frequently diagnosed male cancer and the fifth highest cause of cancer mortality in men. CDR1as has played an essential role in the growth of several malignancies. However, its significance in the progression of prostate cancer has not been investigated. We aimed to investigate the role and mechanism of CDR1as in the development of prostate cancer and identify a new target for diagnostics and treatment. Methods CDR1as siRNA and miR-7-5p mimic were transfected into PC3 and DU145 PCa cell lines and their effects on cellular processes were investigated. Cell viability was measured by WST-8 assay. The role of CDR1as and/or miR-7-5p on PCa cell migration was detected using the scratch-wound assay. The apoptotic capacity of the cells was evaluated using the Caspase-3 kit. The potential targets of miR-7-5p were defined via in silico tools. mRNA and protein expression levels of IGF1R and EIF4E were detected by qRT-PCR and western blot assays, respectively. The matching between miR-7-5p and IGF1R was defined via luciferase reporter assay. Results Inhibiting CDR1as or restoring miR-7-5p reduced prostate cancer cell proliferation and migration while increasing apoptosis. Silencing CDR1as elevated the expression of miR-7-5p while decreasing IGF1R. Conclusions CDR1as functions as a miR-7-5p sponge, increasing IGF1R expression and promoting tumor development.

IGF-1 impacts neocortical interneuron connectivity in epileptic spasm generation and resolution

Little is known about the mechanisms that generate epileptic spasms following perinatal brain injury. Recent studies have implicated reduced levels of Insulin-like Growth Factor 1 (IGF-1) in these patients’ brains. Other studies have reported low levels of the inhibitory neurotransmitter, GABA. In the TTX brain injury model of epileptic spasms, we undertook experiments to evaluate the impact of IGF-1 deficiencies on neocortical interneurons and their role in spasms. Quantitative immunohistochemical analyses revealed that neocortical interneurons that express glutamic acid decarboxylase, parvalbumin, or synaptotagmin 2 co-express IGF-1. In epileptic rats, expression of these three interneuron markers were reduced in the neocortex. IGF-1 expression was also reduced, but surprisingly this loss was confined to interneurons. Interneuron connectivity was reduced in tandem with IGF-1 deficiencies. Similar changes were observed in surgically resected neocortex from infantile epileptic spasms syndrome (IESS) patients. To evaluate the impact of IGF-1 deficiencies on interneuron development, IGF-1R levels were reduced in the neocortex of neonatal conditional IGF-1R knock out mice by viral injections. Four weeks later, this experimental maneuver resulted in similar reductions in interneuron connectivity. Treatment with the IGF-1 derived tripeptide, (1–3)IGF-1, abolished epileptic spasms in most animals, rescued interneuron connectivity, and restored neocortical levels of IGF-1. Our results implicate interneuron IGF-1 deficiencies, possibly impaired autocrine IGF-1 signaling and a resultant interneuron dysmaturation in epileptic spasm generation. By restoring IGF-1 levels, (1–3)IGF-1 likely suppresses spasms by rescuing interneuron connectivity. Results point to (1–3)IGF-1 and its analogues as potential novel disease-modifying therapies for this neurodevelopmental disorder.

Causal associations between the insulin-like growth factor family and sarcopenia: a bidirectional Mendelian randomization study.

Insulin-like growth factor (IGF) is closely associated with sarcopenia, yet the causal relationship of this association remains unclear. This study aims to explore the potential causal relationship between members of the IGF family and sarcopenia from a genetic perspective through bidirectional Mendelian randomization (MR) analysis using two-sample datasets. Five genetically predicted factors of the IGF family (IGF-1, IGF-1R, IGF-2R, IGFBP-3, IGFBP-7) as one sample, while four relevant features of sarcopenia (low hand grip strength, appendicular lean mass, whole body fat-free mass, and walking pace) as another sample, in conducting a two-sample MR analysis. The forward MR results of the relationship between IGF and sarcopenia showed that elevated levels of IGF-1 reduced the risk of low hand grip strength (OR = 0.936, 95% CI=0.892-0.983, P = 0.008) and increased appendicular lean mass of the extremities and whole body fat-free mass (OR = 1.125, 95% CI=1.070-1.182,P = 0.000; OR =1.076, 95% CI=1.047-1.106, P=0.000), reduced the risk of sarcopenia. Elevated IGF-1R also favored an increase in whole body fat-free mass (OR=1.023, 95% CI=1.008-1.038, P =0.002), and the appendicular lean mass trait was more pronounced with elevated IGFBP-3 and IGFBP-7 (OR=1.034, 95% CI=1.024-1.044, P =0.000; OR=1.020, 95% CI=1.010-1.030, P=0.000). Inverse MR results of the effect of sarcopenia on IGF showed that decreased hand grip strength may elevate IGF-1 levels (OR=1.243, 95% CI=1.026-1.505,P =0.027), whereas improvements in appendicular lean mass, whole body fat-free mass traits, and increased walking pace decreased IGF-1 levels (OR=0.902, 95% CI: 0.877-0.927, P = 0.000; OR=0.903, 95% CI=0.859-0.949,P = 0.000; OR=0.209, 95% CI=0.051-0.862,P = 0.045). Also decreased hand grip strength may elevate IGF-1R levels (OR=1.454, 95% CI=1.108-1.909, P =0.007), and appendicular lean mass stimulated high expression of IGFBP-1 (OR=1.314, 95% CI=1.003-1.722, P =0.047). Heterogeneity and pleiotropy were not detected in all results, and the results were stable and reliable. There is a bi-directional causal association between IGF family members and the risk of sarcopenia, which provides a more adequate basis for early biological monitoring of sarcopenia and may provide new targets for early intervention and treatment of sarcopenia.

Hederagenin regulates the migration and invasion of hepatocellular carcinoma cells through FOXO signaling pathway.

This study aimed to elucidate the effects of Hederagenin (HG) on hepatocellular carcinoma (HCC) and explore its potential molecular mechanisms. Virtual screening was employed to identify potential targets within core pathways of liver cancer and to analyze the possible mechanisms of HG. CCK-8 assays were used to assess the viability of HCC cells, while Hoechst 33342/PI staining was utilized to evaluate apoptosis. The migration and invasion abilities of HCC cells were examined using Transwell and scratch assays, and single-cell cloning ability was assessed via colony formation assays. Subsequent qRT-PCR was conducted to determine the mRNA expression levels of FOXO1 and FOXO6 following HG treatment. Western blot (WB) analysis was employed to measure the protein expression levels of IGF1R, FOXO1, FOXO6, MMP2, MMP9, and VEGFA, as well as the phosphorylation status of FOXO1 Ser249. Virtual screening indicated that HG might exert antitumor effects through the FOXO signaling pathway. Experimental results demonstrated that HG induces apoptosis in a dose-dependent manner and inhibits the proliferation, migration, invasion, and single-cell cloning ability of HCC cells. After HG treatment, FOXO1 expression was upregulated, while the expression levels of IGF1R, phosphorylated FOXO1 Ser249, MMP2, MMP9, and VEGFA were downregulated. In summary, our study is the first to demonstrate that HG regulates the phosphorylation of FOXO1, affecting the proliferation, migration, and invasion of HCC cells. The findings suggest that HG can inhibit the migration of HCC cells in vitro. The data indicate that HG-mediated targeting of the FOXO1/FOXO6 pathway holds promise as a novel therapeutic approach.

Dendrobium nobile-derived polysaccharides stimulate the glycolytic pathway by activating SIRT2 to regulate insulin resistance in polycystic ovary syndrome granulosa cells

Insulin resistance (IR) is one of the major complications of polycystic ovary syndrome (PCOS). This study aimed to investigate the effects and the molecular regulatory mechanism by which Dendrobium nobile-derived polysaccharides (DNP) improve IR in rats with letrozole and high-fat-diet induced PCOS. In vivo, DNP (200 mg/kg/d) administration not only reduced body weight, blood glucose, and insulin levels in PCOS rats, but also improve the disrupted estrous cycle. In addition, DNP treatment reduced atretic and cystic follicles and enhanced granulosa cell layer thickness, thereby restoring follicle development. In vitro, DNP treatment (100 μM) increased lactate levels and decreased pyruvate levels in insulin-treated (8 μg/mL) KGN cells. Additionally, DNP also decreased the expression of IGF1 and increased that of IGF1R, SIRT2, LDHA, PKM2 and HK2 both in vivo and in vitro. Also, SIRT2 expression was specifically inhibited by AGK2, while DNP significantly improved IR and glycolysis by reversing the effect of AGK2 treatment on lactate and pyruvate production, upregulating the expression levels of IGF1R, LDHA, HK2, and PKM2 and downregulating the expression level of IGF1. The results indicate that DNP can effectively improve IR and restore glycolytic pathway by activating SIRT2, which may provide a potential therapeutic approach for PCOS patients.

Effect of temperature on growth, expression of growth regulating genes, and deformity development of juvenile European plaice (Pleuronectes platessa)

The flatfish European plaice is a demersal, temperate species and a candidate for marine aquaculture. To better understand growth and the mechanisms involved in growth regulation, juvenile plaice (initial mean weight ± SEM, 10.4 ± 0.1 g) were reared in triplicate rearing tanks at three different temperature: ambient (average of 8.6 °C), 12 °C and 16 °C, for 100 days. Interactions between growth, expression of growth regulating genes, and skeletal development were studied to determine optimal rearing conditions for juvenile plaice. Juvenile plaice grew fastest at 16 °C, followed by the 12 °C group. The condition factor was inversely correlated to increased temperatures and was highest in the 8.6 °C group. At the start of the experiment, 11% of the fish had vertebra deformities. Increasing temperature resulted in higher frequency and severity of malformations, and the 8.6 °C group had 8% less vertebra deformities at the end of the experiment compared to other two groups. The 12 °C and 16 °C groups had similar frequency of deformed fish, however, the 16 °C had more severe deformities, measured as number of deformed vertebrae per fish. Temperature affected gene transcript levels of ghr, igf-1, and igf-1r in muscle and liver tissue differently. Hepatic igf-1 transcript levels increased with increased growth and temperature. Muscular igf-1r transcript levels increased with increasing temperature in each sampling, indicating that igf-1r corresponded with muscular growth. Based on the present findings, a rearing temperature of 12 °C is recommended for on-growing of juvenile plaice.

The miR-15b-5p/miR-379-3p-FOXO axis regulates cell cycle and apoptosis in scleral remodeling during experimental myopia

BackgroundMyopia is one of the most common eye diseases in children and adolescents worldwide, and scleral remodeling plays a role in myopia progression. However, the identity of the initiating factors and signaling pathways that induce myopia-associated scleral remodeling is still unclear. This study aimed to identify biomarkers of scleral remodeling to elucidate the pathogenesis of myopia.MethodsThe gene expression omnibus (GEO) and comparative toxicogenomics database (CTD) mining were used to identify the miRNA-mRNA regulatory network related to scleral remodeling in myopia. Real-time quantitative PCR (RT-qPCR), Western blot, immunofluorescence, H&E staining, Masson staining, and flow cytometry were used to detect the changes in the FOXO signaling pathway, fibrosis, apoptosis, cell cycle, and other related factors in scleral remodeling.ResultsmiR-15b-5p/miR-379-3p can regulate the FOXO signaling pathway. Confirmatory studies confirmed that the axial length of the eye was significantly increased, the scleral thickness was thinner, the levels of miR-15b-5p, miR-379-3p, PTEN, p-PTEN, FOXO3a, cyclin-dependent kinase (CDK) inhibitor 1B (CDKN1B) were increased, and the levels of IGF1R were decreased in Len-induced myopia (LIM) group. CDK2, cyclin D1 (CCND1), and cell cycle block assessed by flow cytometry indicated G1/S cell cycle arrest in myopic sclera. The increase in BAX level and the decrease in BCL-2 level indicated enhanced apoptosis of the myopic sclera. In addition, we found that the levels of transforming growth factor-β1 (TGF-β1), collagen type 1 (COL-1), and α-smooth muscle actin (α-SMA) were decreased, suggesting scleral remodeling occurred in myopia.ConclusionsmiR-15b-5p/miR-379-3p can regulate the scleral cell cycle and apoptosis through the IGF1R/PTEN/FOXO signaling pathway, thereby promoting scleral remodeling in myopia progression.Graphical

Neohesperidin alleviates the inhibitory effect of bisphenol A on the myogenic differentiation of umbilical cord mesenchymal stem cells via the IGF1R/AKT1/RHOA signaling pathway

Bisphenol A (BPA), a typical environmental endocrine disruptor, has raised concerns among researchers due to its toxicological effects. Whether neohesperidin (NEO) can intervene in the toxic effects of BPA remains unknown. This study aims to investigate the effects and mechanisms of NEO on the myogenic differentiation of umbilical cord-derived mesenchymal stem cells (UC-MSCs) exposed to BPA. Sheep UC-MSCs were isolated, characterized, and induced to myogenic differentiation. BPA decreased cell viability, cell migration, and the expressions of myogenic marker genes, leading to myogenic differentiation inhibition, which were reversed by NEO. Network pharmacology suggested the IGF1R/AKT1/RHOA pathway as potential targets of BPA and NEO regulating muscle development. Western blot results showed that NEO could reverse the down-regulation of the pathway proteins induced by BPA, and counteract the effects of picropodophyllin (PPP) or MK-2206 dihydrochloride (MK-2206) in the myogenic differentiation of sheep UC-MSCs. Additionally, the expression levels of (p-) IGF1R, AKT1, and RHOA were positively correlated. Taken together, the mechanisms of NEO resistance to BPA involved the IGF1R/AKT1/RHOA signaling pathway. These findings provide a scientific basis for alleviating BPA toxicity, preventing and treating muscular dysplasia, and promoting muscle damage repair.

Effects of spectral on growth, physiology, and growth axis gene expression in Plectropomus leopardus

This study examined the effect of different spectral on the growth, feeding rate, digestion, and metabolism of Plectropomus leopardus in an industrial recirculating aquaculture system. All Plectropomus leopardus (wet weight 100 g ± 0.45 g) were kept in triplicate tanks for 60 days under six different spectral full visual (400 to 800 nm), blue (450 nm), green (530 nm), yellow (590 nm), red (630 nm) spectrum, and dark. After the experiment, fish were weighed and sampled to obtain haemolymph, brain, and hepatopancreas tissues, which were used to analyze biochemical parameters and gene expression. The findings indicated that the group exposed to blue light demonstrated substantially elevated feeding rate, weight gain, specific growth rate, and reduced feed conversion ratios and visceral-somatic indexes compared to the other groups (p < 0.05). The blue light and full spectrum groups had considerably increased levels of digestive, metabolic, and antioxidant enzyme activity compared to the other groups (p < 0.05). The expression levels of GH, GHR, PACA, ADCY, IGFI, IGFIR, and IGFBP growth axis genes in the brain and liver were significantly higher in the blue light group than in the other groups (p < 0.05). The results indicate that spectral impact the growth, feeding rate, digestion, and metabolism of P. leopardus. This study revealed distinct spectra that enhanced the growth rate and increased the weight gain from feeding. Furthermore, the optimal spectral composition for recycling aquaculture of P. leopardus was clarified, thereby providing theoretical references for designing lighting strategies in indoor recycling aquaculture systems tailored to P. leopardus.

Exploration and optimisation of structure-activity relationships of new triazole-based C-terminal Hsp90 inhibitors towards in vivo anticancer potency

The development of new anticancer agents is one of the most urgent topics in drug discovery. Inhibition of molecular chaperone Hsp90 stands out as an approach that affects various oncogenic proteins in different types of cancer. These proteins rely on Hsp90 to obtain their functional structure, and thus Hsp90 is indirectly involved in the pathophysiology of cancer. However, the most studied ATP-competitive inhibition of Hsp90 at the N-terminal domain has proven to be largely unsuccessful clinically. Therefore, research has shifted towards Hsp90 C-terminal domain (CTD) inhibitors, which are also the focus of this study. Our recent discovery of compound C has provided us with a starting point for exploring the structure-activity relationship and optimising this new class of triazole-based Hsp90 inhibitors. This investigation has ultimately led to a library of 33 analogues of C that have suitable physicochemical properties and several inhibit the growth of different cancer types in the low micromolar range. Inhibition of Hsp90 was confirmed by biophysical and cellular assays and the binding epitopes of selected inhibitors were studied by STD NMR. Furthermore, the most promising Hsp90 CTD inhibitor 5x was shown to induce apoptosis in breast cancer (MCF-7) and Ewing sarcoma (SK-N-MC) cells while inducing cause cell cycle arrest in MCF-7 cells. In MCF-7 cells, it caused a decrease in the levels of ERα and IGF1R, known Hsp90 client proteins. Finally, 5x was tested in zebrafish larvae xenografted with SK-N-MC tumour cells, where it limited tumour growth with no obvious adverse effects on normal zebrafish development.

The receptor tyrosine kinase IGF1R and its associated GPCRs are co-regulated by the noncoding RNA NEAT1 in Alzheimer’s disease

The study is based on the complexity of Insulin like growth factor receptor (IGF1R) signaling and its regulation by noncoding RNAs (ncRNAs). IGF1R signaling is an important cascade in Alzheimer’s disease (AD); however, its regulation and roles are poorly understood. Due to the presence of β-arrestin and GPCR Receptor Kinase binding sites, this protein has been termed a ‘functional hybrid’, as it can take part in both kinase and GPCR signaling pathways, further adding to its complexity. The objective of this study is to understand the underlying ncRNA regulation controlling IGF1R and GPCRs in AD to find commonalities in the network. We found through data mining that 45 GPCRs were reportedly deregulated in AD and built clusters based on GO/KEGG pathways to show shared functionality with IGF1R. Eight miRs were further discovered that could coregulate IGF1R and GPCRs. We validated their expression in an AD cell model and probed for common lncRNAs downstream that could regulate these miRs. Seven such candidates were identified and further validated. A combined network comprising IGF1R with nine GPCRs, eight miRs, and seven lncRNAs was created to visualize the interconnectivity within pathways. Betweenness centrality analysis showed a cluster of NEAT1, hsa-miR-15a-5p, hsa-miR-16-5p, and IGF1R to be crucial form a competitive endogenous RNA-based (ceRNA) tetrad that could relay information within the network, which was further validated by cell-based studies. NEAT1 emerged as a master regulator that could alter the levels of IGF1R and associated GPCRs. This combined bioinformatics and experimental study for the first time explored the regulation of IGF1R through ncRNAs from the perspective of neurodegeneration.

The Effect of Different Exercise Modalities on Sertoli-germ Cells Metabolic Interactions in High-fat Diet-induced Obesity Rat Models: Implication on Glucose and Lactate Transport, Igf1, and Igf1R-dependent Pathways.

The study aimed to uncover a unique aspect of obesity-related metabolic disorders in the testicles induced by a high-fat diet (HFD) and explored the potential mitigating effects of exercise modalities on male fertility. Thirty mature male Wistar rats were randomly assigned to control, HFD-sole, moderate-intensity exercise with HFD (HFD+MICT), high-intensity continuous exercise with HFD (HFD+HICT), and high-intensity interval exercise with HFD (HFD+HIIT) groups (n=6/group). Intracytoplasmic carbohydrate (ICC) storage, expression levels of GLUT-1, GLUT-3, MCT-4, Igf1, and Igf1R, and testicular lactate and lactate dehydrogenase (LDH) levels were assessed. ICC storage significantly decreased in HFD-sole rats, along with decreased mRNA and protein levels of GLUT-1, GLUT-3, MCT-4, Igf1, and Igf1R. The HFD-sole group exhibited a notable reduction in testicular lactate and LDH levels (p<0.05). Conversely, exercise, particularly HIIT, upregulated ICC storage, expression levels of GLUT-1, GLUT-3, MCT-4, Igf1, and Igf1R, and enhanced testicular lactate and LDH levels. These results confirm that exercise, especially HIIT, has the potential to mitigate the adverse effects of HFD-induced obesity on testicular metabolism and male fertility. The upregulation of metabolite transporters, LDH, lactate levels, Igf1, and Igf1R expression may contribute to maintaining metabolic interactions and improving the glucose/lactate conversion process. These findings underscore the potential benefits of exercise in preventing and managing obesity-related male fertility issues.

Sex-based differences in growth-related IGF1 signaling in response to PAPP-A2 deficiency: comparative effects of rhGH, rhIGF1 and rhPAPP-A2 treatments

BackgroundChildren with pregnancy-associated plasma protein-A2 (PAPP-A2) mutations resulting in low levels of bioactive insulin-like growth factor-1 (IGF1) and progressive postnatal growth retardation have improved growth velocity and height following recombinant human (rh)IGF1 treatment. The present study aimed to evaluate whether Pappa2 deficiency and pharmacological manipulation of GH/IGF1 system are associated with sex-specific differences in growth-related signaling pathways.MethodsPlasma, hypothalamus, pituitary gland and liver of Pappa2ko/ko mice of both sexes, showing reduced skeletal growth, and liver of these mice treated with rhGH, rhIGF1 and rhPAPP-A2 from postnatal day (PND) 5 to PND35 were analyzed.ResultsReduced body and femur length of Pappa2ko/ko mice was associated with increases in: (1) components of IGF1 ternary complexes (IGF1, IGFBP5/Igfbp5, Igfbp3, Igfals) in plasma, hypothalamus and/or liver; and (2) key signaling regulators (phosphorylated PI3K, AKT, mTOR, GSK3β, ERK1/2 and AMPKα) in hypothalamus, pituitary gland and/or liver, with Pappa2ko/ko females having a more prominent effect. Compared to rhGH and rhIGF1, rhPAPP-A2 specifically induced: (1) increased body and femur length, and reduced plasma total IGF1 and IGFBP5 concentrations in Pappa2ko/ko females; and (2) increased Igf1 and Igf1r levels and decreased Ghr, Igfbp3 and Igfals levels in the liver of Pappa2ko/ko females. These changes were accompanied by lower phospho-STAT5, phospho-AKT and phospho-ERK2 levels and higher phospho-AMPK levels in the liver of Pappa2ko/ko females.ConclusionsSex-specific differences in IGF1 system and signaling pathways are associated with Pappa2 deficiency, pointing to rhPAPP-A2 as a promising drug to alleviate postnatal growth retardation underlying low IGF1 bioavailability in a female-specific manner.

Abstract B040: Trispecific killer engagers against IGF1R and fetal form of insulin receptor induce human natural killer cell mediated killing of hormone receptor positive breast cancer in vitro and in vivo

Abstract Patients with hormone receptor-positive (HR+) breast cancers frequently recur with metastatic disease 5-20 years after the initial diagnosis and completion of chemotherapy and prolonged treatment with hormonal therapy. Thus, patients with metastatic HR+ breast cancer need new therapeutic options. A potential mechanism of therapeutic resistance in HR+ patients is the presence of slow-growing, well-differentiated cancer cells that result in clinically detectable metastases after a prolonged latency. One way to eliminate these cancer cells is with immunotherapy (IT). Unfortunately HR+ breast cancers have not responded to current T-cell based IT. The objective of this study is to target HR+ breast cancers using a natural killer (NK) cell based approach that targets cell surface receptors in HR+ breast cancer. The type I IGF receptor (IGF1R) is expressed on HR+ breast cancers and its expression is tightly related to ER function. Endocrine therapy resistance is associated with increased expression of the A-isoform or fetal form of IR (IR-A) and depend on IR signaling. We hypothesized that a drug that would target NK cells to IGF1R or IR-A expressing HR+ cells will be effective in killing them. We generated IGF1R or IR-A specific Tri specific Killer Engagers (TriKE) that leverage expression of IGF1R and IR-A on HR+ cells to cause NK directed death. The IGF1R TriKE consists of humanized single domain antibody (VHH) sequence of a CD16 nanobody to engage and activate NK cells, a humanized VHH of a nanobody against IGF1R to target HR+ breast cancer cells, and an IL-15 molecule between them to drive NK cell expansion and survival. The IGF1R TriKE did not bind embryonal fibroblasts from IGF1R knock out mice (R- cells) but bound R-/IGF1R cells (R- cells engineered to express human IGF1R) and to IGF1R+ MCF-7 and T47D breast cancer cells indicating specific binding to IGF1R on cells. It did not cause downregulation of IGF1R levels in multiple HR+ breast cancer cells and did not inhibit signaling via IGF1R. It specifically induced NK cell degranulation, measured by surface CD107a expression and intracellular IFNγ, against IGF1R+ target breast cancer cells (MCF-7, T-47D, ZR-75-1) in a functional assay compared to the anti-IGF1R nanobody. It did not induce degranulation of NK cells against IGF1R negative cells suggesting that the functionality was specific for IGF1R expressing targets. The IGF1R TriKE enhanced cell killing of HR+ breast cancer cells as measured by cytotoxicity assays. IGF1R TriKE combined with human NK cells inhibited tumor growth of MCF-7 tumors in NSG mice compared to control groups. Human NK cells persisted in peripheral blood three weeks after final NK infusion based on flow cytometry assessment. The IR-A TriKE incorporated a novel engineered non-immunoglobulin IR-A specific peptide binder. Our preliminary data show that the IR-A TriKE degranulated NK cells against breast cancer cells overexpressing IR-A. These data indicate that this strategy could be an effective treatment for HR+ metastatic breast cancer and make them responsive to IT. Citation Format: Courtney Baar, Emily Chiu, Yvette Soignier, Behiye Kodal, Jeffrey S Miller, Martin Felices, Deepali Sachdev. Trispecific killer engagers against IGF1R and fetal form of insulin receptor induce human natural killer cell mediated killing of hormone receptor positive breast cancer in vitro and in vivo [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr B040.

Molecular characteristics of IGF and IGF1R genes and their potential roles on longevity in two scallops with distinct lifespans

Bay scallops are commercially important bivalve species for aquaculture worldwide, but the serious inbreeding depression is decreasing their production. Some interspecific hybrids of bay scallops (Argopecten irradians irradians) and Peruvian scallops (A. purpuratus) exhibit longer lifespan and significantly larger size for high yield, which may result from the longevity genes of Peruvian scallops. Insulin-like growth factor (IGF) system, as the conspicuous entry point of insulin/insulin-like growth factor signal (IIS) pathway, regulates various cellular processes including growth, autophagy, aging and longevity, but its roles remain unexplored in marine animals. In this study, we separately cloned a unique IGF2 (ApIGF2 and AiIGF2) and IGF1R (ApIGF1R and AiIGF1R) for the first time from two closely related Argopecten scallops with distinct lifespans and characterized for their ability to regulate longevity. Sequence analysis demonstrated that there were six-span transmembrane domains located at the additional extension of C-terminus special to AiIGF2, which appeared to relate to the differences in posttranslational processing. The amino acid variation (Y247) in TyrKc domain may be a key site affecting ApIGF1R kinase activity for longevity. Spatiotemporal expression of IGF2 and IGF1R during development and aging showed that the mantle and gonad are representative tissues for aging in scallops. The dietary restriction assay revealed the beneficial effects of attenuated IGF2 and IGF1R levels on longevity in scallops. The invigorated IGF1R conferred DNA repair and prosurvival properties to Peruvian scallops for radio-resistance after acute radioresistance. Inhibition of AiIGF1R upregulated the expression of senescence-associated genes (PENT, FoxO, CAT, Mn-SOD) and antioxidant enzyme activities, and suppressed the senescence marker β-GAL activity, indicating that IGF1R was a crucial regulator for longevity in scallops. Collectively, our work would bring us closer to understanding the longevity mechanism mediated by IGF system and breeding larger and long-lived hybrids for the sustainable development of aquaculture.

SAT047 Regulation Of The Insulin Receptor And The Insulin-like Growth Factor 1 Receptor By miR-322-5p, A miR-16 Family Member, In Hypothalamic Neuronal Models

Abstract Disclosure: W. He: None. N. Loganathan: None. K.W. Mak: None. E. McIlwraith: None. D.D. Belsham: None. Insulin signals through the insulin receptor (INSR) and the insulin-like growth factor 1 receptor (IGF1R) in hypothalamic neurons to control food intake and peripheral metabolism. A contributor to obesity, and subsequent comorbidities such type 2 diabetes and heart disease, is the development of cellular insulin resistance in hypothalamic neurons. However, the molecular changes to neuronal insulin signaling remain to be fully elucidated. MicroRNAs (miRNAs) inhibit translation of specific mRNAs; thus, this study aimed to understand the involvement of miRNAs in the regulation of insulin signaling and resistance in hypothalamic neurons. To profile miRNAs expressed in hypothalamic neurons, RNA from the whole hypothalami of 14-week-old CD1 male mice (n = 4), as well as the immortalized hypothalamic neuronal cell lines mHypoE-46 (n = 3) and mHypoA-59 (n = 3), each co-expressing neuropeptide Y (NPY) and agouti-related peptide (AgRP), were assessed using the Affymetrix GeneChip miRNA 4.0 Array. Notably, miR-16 family members, including miR-16-5p, miR-15b-5p, and miR-322-5p, were among the most highly expressed miRNAs in each case. In the mHypoA-59 neurons, overexpression of miR-322-5p for 24 hours decreased the mRNA levels of Igf1r (-26.1%; p = 0.0007; n = 4) and the protein level of INSR-beta (-31.8%; p = 0.0023). These results suggest that the miR-16 family plays an inhibitory role in insulin signaling in hypothalamic neurons. To study the involvement of miRNAs in hyperinsulinemia-induced neuronal insulin resistance, the mHypoE-46 neurons were treated with 100 nM insulin for 24 hours to induce cellular insulin resistance, as characterized by decreased INSR-beta protein (-96.3%; p &amp;lt; 0.0001; n = 4) and a resulting decrease in insulin-induced phosphorylation of protein kinase B (AKT) (-67.6%; p = 0.01; n = 4). GeneChip miRNA array analysis showed that insulin overexposure disrupted the expression of 48 miRNAs (p &amp;lt; 0.05, n = 3), including the upregulation of miR-18a-3p, mir-322, miR-494-3p, and miR-671-3p. Upon RT-qPCR validation (n = 3), we established that prolonged (24 hours), but not acute (1-6 hours), insulin exposure upregulated miR-18a-3p (+62%; p = 0.0104), miR-671-3p (+111%; p = 0.0079), and miR-1983 (+97%; p = 0.0181). miR-671-3p, miR-494-3p, and miR-18a-3p have been shown to decrease phosphatase and tensin homolog (PTEN) levels, which can promote neuronal insulin resistance based on bioinformatic analysis. Overall, these results suggest hyperinsulinemia disrupts the expression of specific miRNAs in hypothalamic neurons to promote cellular insulin resistance. Knowledge derived from these studies will provide insight into hypothalamus-derived miRNAs that could be targeted for miRNA-based diagnostics and therapeutics for early central insulin resistance in humans.(Supported by the CRC, CIHR, NSERC, EndoSoc, and BBDC) Presentation: Saturday, June 17, 2023

Abstract 1697: Role of intra-tumoral bacteria in EGFR-tyrosine kinase inhibitor resistance

Abstract Although most lung cancers with EGFR-mutation respond to osimertinib, resistance eventually develops, and there are no approved targeted therapies once resistance to osimertinib occurs. Intra-tumoral bacteria are emerging as a cause of therapy resistance in cancer. In order to determine if intra-tumoral bacteria play a role in the resistance of EGFR-mutant lung cancers to EGFR-TKIs, including osimertinib, we used a bacterial pre-conditioned medium (PCM) screening system which utilized various bacteria identified in lung cancer specimens. We used a cell viability evaluation method in GFP-labeled PC9 cells (EGFR Ex19del) to identify the bacterial PCM that may lead to resistance to EGFR-TKIs. We found that PCM from Chryseobacterium indologenes (C-PCM) markedly rescued PC9 from osimertinib. Furthermore, we found that C-PCM also could increase cell viability in other EGFR-mutated cell lines HCC4006, HCC827, and H1650. We found that proteinase K treatment eliminated the rescue of C-PCM on EGFR-TKI treatment, indicating that proteins within C-PCM are responsible for its effect of EGFR-TKI treatment. Mass spectrometry (MS) analysis showed that C-PCM does not degrade osimertinib, suggesting that C-PCM mediated resistance does not occur through drug degradation. To understand the mechanism by which C-PCM meditates resistance to osimertinib in NSCLC, we performed phosphor-Receptor Kinase Array to detect changes in phosphorylation between C-PCM and non-C-PCM treatment in PC9 cells. This showed no change in phosphorylation levels of EGFR, indicating that rescue from osimertinib is not through re-activation of EGFR pathway. However, phosphorylation levels of MET and IGF1R were significantly increased when C-PCM was applied to PC9 cells regardless of the presence or absence of osimertinib. Knockdown of IGF1R significantly increased the sensitivity of PC9 cell to osimertinib. Similar results were observed in siMET-PC9 cells. Interestingly, we found that C-PCM lost its ability to rescue PC9 cells from osimertinib when IGF1R was knocked down. Also, inhibition of IGF1R activation by the IGF1R inhibitor linsitinib increased PC9 cell sensitivity to osimertinib, and C-PCM rescue ability decreased with increased linsitinib concentration. Even though MET knockdown increased PC9 cell sensitivity to osimertinib, C-PCM still could increase cell viability with MET knockdown. These results together indicate that activation of IGF1R may be the main pathway that mediates Chryseobacterium indologenes resistance to osimertinib. Further mechanistic studies of C-PCM mediated resistance are underway to understand the precise mechanism of bacterial-mediated EGFR-TKI resistance. Additional research on the clinical relevance of these findings may lead to new strategies to overcome EGFR-TKI-resistance. Citation Format: Wendong Li, Keqiang Zhang, Aviva Rotter-Maskowitz, Deborah Nejman, Ravid Straussman, Dan Raz. Role of intra-tumoral bacteria in EGFR-tyrosine kinase inhibitor resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1697.

Abstract 2567: Exploring novel roles of the GPCR Smoothened in AKT signaling and drug resistance

Abstract The Smoothened receptor (SMO) belongs to the frizzled-class-G-protein coupled receptor and its activity can be classified in the canonical and the non-canonical pathway. The canonical pathway concludes in the transcriptional activation of the Hedgehog target genes through the GLI family of transcription factors whereas the non-canonical pathway leads to the recruitment and activation of trimeric G proteins. Recently, we have reported two novel roles of SMO with relevance to cell survival and drug resistance in DLBCL. In the first, SMO promotes a shift in the ubiquitination pattern for TNF receptor-associated factor 6 (TRAF6) from degradation inducing K48-ubiquitin branching towards K63-ubiquitination. TRAF6 is a K63-Ub E3 ubiquitin ligase for AKT and K63-ubiquitination of AKT increases membrane recruitment, activation and stability. Evidently, SMO promotes the formation of a scaffold-like protein complex including the de-ubiquitinating enzyme Ubiquitin specific peptidase 8 (USP8) and TRAF6. In its second novel role, SMO influences the vesicular sorting of IGF1R and other receptor tyrosine kinases. Loss of SMO leads to increased IGF1R lysosomal degradation and reduced IGF1R recycling, while overexpression increases IGF1R levels and AKT signaling. These observations indicate SMO receptor biology outside of the established canonical and non-canonical pathway functions. We have set out to use BioID to investigate the SMO interactome that contributes to these novel functionalities using a fusion protein of SMO and the reengineered E. coli biotinyl transferase BirA (Turbo) as bait. Preliminary BioID using SMO-Turbo returned a list of candidates which will require further data filtering approaches, but thus far shows a marked enrichment for proteins involved in vesicular trafficking. Citation Format: Samantha Manuel, Nitin Agarwal, Daniel Bilbao, Francisco Vega, Ralf Landgraf. Exploring novel roles of the GPCR Smoothened in AKT signaling and drug resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2567.