Insulin-like Growth Factor-1 Receptor Protein Research Articles

Association between Expression of Insulin-like Growth Factor-1 (IGF-1), IGF-1 Receptor (IGF-1R), and Hypertension-Mediated Organ Damage (HMOD) Parameters in Leukocytes and Plasma of Children/Adolescents with Primary Hypertension.

A decrease in IGF-1 is often linked to inflammation. Low systemic and local IGF-1 production and downregulation of IGF-1R expression may precede and predict PH development in children/adolescents. Leukocyte mRNA expression of IGF-1 and its receptor (IGF-1R) and plasma IGF-1 were measured in a group of 39 PH children/adolescents (29 boys and 10 girls) and 35 age-matched normotensive children (19 boys and 16 girls) using the RT-PCR and ELISA tests. The expression of the IGF-1R protein was assessed by flow cytometry. Plasma IGF-1 concentration was evaluated with ELISA. The expression of IGF-1 and IGF-1R and plasma concentrations of IGF-1 did not differ between groups. However, the PH children had a decreased percentage in IGF-1R-bearing lymphocytes (p = 0.02) and monocytes (p = 0.0003), as well as a low density of IGF-R in monocytes (p = 0.02). The IGF-1 expression was negatively correlated with pulse-wave velocity (PWV) (r = -0.49), systolic blood pressure (SBP) (-0.44), and carotid intima-media thickness (cIMT) (-0.43). The IGF-1R expression was negatively correlated with PWV (r = -0.42) and SBP (r = -0.41). Our results suggest that early subclinical hypertensive arterial injury is associated with lower activity of IGF-1-IGF-1R expression and loss of protective actions.

The in vitro and in vivo antiviral effects of IGF1R inhibitors against respiratory syncytial virus infection

The insulin-like growth factor 1 receptor (IGF1R) was recognized as a pivotal receptor that facilitated the cellular entry of RSV. Small molecule inhibitors designed to target IGF1R exhibited potential as potent antiviral agents. Through virtual screening, we conducted a screening process involving small molecule compounds derived from natural products, aiming to target the IGF1R protein against respiratory syncytial virus infection. The molecular dynamics simulation analysis showed that tannic acid and daptomycin interacted with the IGF1R. The experimental results in vivo and in vitro showed that tannic acid and daptomycin had anti-RSV infection potential through reducing viral loads, inflammation, airway resistance and protecting alveolar integrity. The CC50 values of tannic acid and daptomycin were 6 nM and 0.45 μM, respectively. Novel small-molecule inhibitors targeting the IGF1R, tannic acid and daptomycin, may be effective anti-RSV therapy agents. This study may in future broaden the arsenal of therapeutics for use against RSV infection and lead to more effective care against the virus. Communicated by Ramaswamy H. Sarma

A viral insulin-like peptide inhibits IGF-1 receptor phosphorylation and regulates IGF1R gene expression

ObjectiveThe insulin/IGF superfamily is conserved across vertebrates and invertebrates. Our team has identified five viruses containing genes encoding viral insulin/IGF-1 like peptides (VILPs) closely resembling human insulin and IGF-1. This study aims to characterize the impact of Mandarin fish ranavirus (MFRV) and Lymphocystis disease virus-Sa (LCDV-Sa) VILPs on the insulin/IGF system for the first time. MethodsWe chemically synthesized single chain (sc, IGF-1 like) and double chain (dc, insulin like) forms of MFRV and LCDV-Sa VILPs. Using cell lines overexpressing either human insulin receptor isoform A (IR-A), isoform B (IR-B) or IGF-1 receptor (IGF1R), and AML12 murine hepatocytes, we characterized receptor binding, insulin/IGF signaling. We further characterized the VILPs’ effects of proliferation and IGF1R and IR gene expression, and compared them to native ligands. Additionally, we performed insulin tolerance test in CB57BL/6 J mice to examine in vivo effects of VILPs on blood glucose levels. Finally, we employed cryo-electron microscopy (cryoEM) to analyze the structure of scMFRV-VILP in complex with the IGF1R ectodomain. ResultsVILPs can bind to human IR and IGF1R, stimulate receptor autophosphorylation and downstream signaling pathways. Notably, scMFRV-VILP exhibited a particularly strong affinity for IGF1R, with a mere 10-fold decrease compared to human IGF-1. At high concentrations, scMFRV-VILP selectively reduced IGF-1 stimulated IGF1R autophosphorylation and Erk phosphorylation (Ras/MAPK pathway), while leaving Akt phosphorylation (PI3K/Akt pathway) unaffected, indicating a potential biased inhibitory function. Prolonged exposure to MFRV-VILP led to a significant decrease in IGF1R gene expression in IGF1R overexpressing cells and AML12 hepatocytes. Furthermore, insulin tolerance test revealed scMFRV-VILP's sustained glucose-lowering effect compared to insulin and IGF-1. Finally, cryo-EM analysis revealed that scMFRV-VILP engages with IGF1R in a manner closely resembling IGF-1 binding, resulting in a highly analogous structure. ConclusionsThis study introduces MFRV and LCDV-Sa VILPs as novel members of the insulin/IGF superfamily. Particularly, scMFRV-VILP exhibits a biased inhibitory effect on IGF1R signaling at high concentrations, selectively inhibiting IGF-1 stimulated IGF1R autophosphorylation and Erk phosphorylation, without affecting Akt phosphorylation. In addition, MFRV-VILP specifically regulates IGF-1R gene expression and IGF1R protein levels without affecting IR. CryoEM analysis confirms that scMFRV-VILP’ binding to IGF1R is mirroring the interaction pattern observed with IGF-1. These findings offer valuable insights into IGF1R action and inhibition, suggesting potential applications in development of IGF1R specific inhibitors and advancing long-lasting insulins.

Inhibitory Effect of Iron Oxide Nanoparticle Liposome on the Growth of Non-Small Cell Lung Cancer In Vitro

In this study, we assessed the inhibitory potential of magnetic liposomes as gene vectors targeting human non-small cell lung cancer (NSCLC) growth In Vitro via hairpin RNA (shRNA) under the influence of an external magnetic field. Specifically, we engineered the plasmid pGFPshIGF-1R to co-express green fluorescent protein (GFP) and shRNA against insulin-like growth factor-1 receptor (IGF-1R), a gene associated with NSCLC progression. Utilizing superparamagnetic iron oxide nanoparticles (CombiMAG) and Lipofectamine2000,we constructed magnetic liposomes to deliver pGFPshIGF-1R into A549 NSCLC cells. Varying magnetic field strengths and exposure times were employed. The efficacy of transfection was gauged against liposome-only methods using Western blot analysis to measure IGF-1R protein reduction. In Vitro, the magnetic approach exhibited higher transfection efficiency (66.3%) compared to liposomes alone (22.1%), marking a threefold enhancement. In vivo, using a subcutaneous A549 tumor model in nude mice, shRNA-transfected A549 cells displayed substantial IGF-1R protein inhibition (interference rates: 56.1% and 85.1%). Importantly, magnetic transfection outperformed liposomal transfection in suppressing IGF-1R protein expression (P <0.05). Our findings suggest that magnetic liposome-mediated gene delivery, facilitated by an external magnetic field, holds promise as a targeted and safe therapeutic strategy for lung cancer.

Effect of 20-hydroxyecdysone and its metabolites in the absence or presence of IGF-1 on regulation of skeletal muscle cell growth

Purpose: To investigate the effect of 20-hydroxyecdysone (20E) and its metabolites and their synergistic effect with IGF-1 on regulation of skeletal muscle cell growth.
 Methods: Mouse skeletal muscle cell line (C2C12) was solely treated with 20E and its metabolites (14- deoxy- 20-hydroxyecdysone, poststerone, and 14-deoxypoststerone) at doses of 0.1, 1, and 10 µM or co-treated with IGF-1 (10 ng/ml). Cell viability and proliferative capacity were evaluated using MTT and BrdU incorporation assays, respectively. Myogenic differentiation proteins [embryonic myosin heavy chain (EbMHC) and MHC], androgen receptor (AR), and IGF-1 receptor (IGF-1R) protein expression were investigated using immunocytochemistry.
 Results: Treatments of 20E and its metabolites had no toxicity on skeletal muscle cells or induced AR/IGF-1R expression. In addition, solely treatment of 20E and its metabolites or co-treatment with IGF-1 had no significant effect on cell proliferation and myogenic differentiation capacity. In contrast, IGF-1 treatment alone significantly increased EbMHC expression (p<0.0001), MHC expression (p<0.05), and myotube number (p<0.05).
 Conclusion: These results indicate that 20E and its metabolites have no direct or synergistic effect with IGF-1 on skeletal muscle cell growth. Nevertheless, the pharmacological effects of 20E on skeletal muscle mass and strength in vivo that raises its therapeutic potential may associate with its indirect action.

Lower muscle protein synthesis in humans with obesity concurrent with lower expression of muscle IGF1 splice variants.

This study tested the hypothesis that expression of insulin-like growth factor 1 (IGF-1) protein and mRNA splice variants is lower in skeletal muscle of humans with obesity who have a lower mixed-muscle protein fractional synthesis rate (MMP-FSR) when compared with individuals without obesity. The study included nine participants with obesity (OB, mean [SD], BMI = 35 [3] kg/m2 , MMP-FSR = 0.06%/h [0.02%/h]) and nine participants without obesity (W-OB, BMI = 24 [3] kg/m2 , MMP-FSR = 0.08%/h [0.02%/h]; for both BMI and MMP-FSR p < 0.05). MMP-FSR and mitochondrial protein FSR were measured following an overnight fast. Along with lower MMP-FSR, OB participants displayed lower mitochondrial protein FSR (p = 0.03) compared with W-OB participants. Expression of IGF-1 (p = 0.04) and IGF-1 receptor (p < 0.01) proteins was lower in muscle of OB participants. In addition, OB participantshad lower (p < 0.05) mRNA expression of IGF1 variants Eb and Ec. This study demonstrates that lower protein synthesis in muscle of humans with obesity occurs concurrently with lower expression of muscle IGF-1 and IGF-1 receptor proteins, as well as lower mRNA expression of the IGF1 splice variants. These findings indicate that lower protein synthesis observed in muscle of humans with obesity may result from diminished muscle IGF1 gene expression.

Role of let-7 family in the invasion and metastasis of osteosarcoma.

Role of let-7 family in the invasion and metastasis of osteosarcoma.

MiR-194-5p suppresses the warburg effect in ovarian cancer cells through the IGF1R/PI3K/AKT axis

Background: The Warburg effect is considered as a hallmark of various types of cancers, while the regulatory mechanism is poorly understood. Our previous study demonstrated that miR-194-5p directly targets and regulates insulin-like growth factor1 receptor (IGF1R). In this study, we aimed to investigate the role of miR-194-5p in the regulation of the Warburg effect in ovarian cancer cells. Methods: The stable ovarian cell lines with miR-194-5p overexpression or silencing IGF1R expression were established by lentivirus infection. ATP generation, glucose uptake, lactate production and extracellular acidification rate (ECAR) assay were used to analyze the effects of aerobic glycolysis in ovarian cancer cells. Gene expression was analyzed by quantitative polymerase chain reaction (qPCR) and western blot. Immunohistochemistry assays were performed to assess the expression of the IGF1R protein in ovarian cancer tissues. Results: Overexpression of miR-194-5p or silencing IGF1R expression in ovarian cancer cells decreases ATP generation, glucose uptake, lactate production, and ECAR and inhibits both the mRNA and protein expression of PKM2, LDHA, GLUT1, and GLUT3. While the knockdown of miR-194-5p expression led to opposite results. Overexpression of miR-194-5p or silencing IGF1R expression suppressed the phosphatidylinositol-3-kinase/protein kinase B (PI3K/AKT) pathway, whose activation can sustain aerobic glycolysis in cancer cells, and the knockdown of miR-194-5p expression promoted the activation of the PI3K/AKT pathway. Conclusion: Our results suggest that miR- 194-5p can inhibit the Warburg effect by negative regulation of IGF1R and further repression of the PI3K/AKT pathway, which provides a theoretical basis for further test of miR-194-5p as a target in the treatment of ovarian cancer.

GRP94 Inhabits the Immortalized Porcine Hepatic Stellate Cells Apoptosis under Endoplasmic Reticulum Stress through Modulating the Expression of IGF-1 and Ubiquitin.

Endoplasmic reticulum stress (ERS) is closely related to the occurrence and progression of metabolic liver disease. The treatment targeting glucose-regulated protein 94 (GRP94) for liver disease has gotten much attention, but the specific effect of GRP94 on hepatocyte apoptosis is still unclear. So far, all the studies on GRP94 have been conducted in mice or rats, and little study has been reported on pigs, which share more similarities with humans. In this study, we used low-dose (LD) and high-dose (HD) tunicamycin (TM) to establish ERS models on piglet livers and immortalized porcine hepatic stellate cells (HSCs). On the piglet ERS model we found that ERS could significantly (p &lt; 0.01) stimulate the secretion and synthesis of insulin-like growth factor (IGF-1), IGF-1 receptor (IGF-1R), and IGF-binding protein (IGFBP)-1 and IGFBP-3; however, with the increase in ERS degree, the effect of promoting secretion and synthesis significantly (p &lt; 0.01) decreased. In addition, the ubiquitin protein and ubiquitination-related gene were significantly increased (p &lt; 0.05) in the LD group compared with the vehicle group. The protein level of Active-caspase 3 was significantly increased (p &lt; 0.01) in the HD group, however, the TUNEL staining showed there was no significant apoptosis in the piglet liver ERS model. To explore the biofunction of ER chaperone GRP94, we used shRNA to knock down the expression of GRP94 in porcine HSCs. Interestingly, on porcine HSCs, the knockdown of GRP94 significantly (p &lt; 0.05) decreased the secretion of IGF-1, IGFBP-1 and IGFBP-3 under ERS, but had no significant effect on these under normal condition, and knockdown GRP94 had a significant (p &lt; 0.01) effect on the UBE2E gene and ubiquitin protein from the analysis of two-way ANOVA. On porcine HSCs apoptosis, the knockdown of GRP94 increased the cell apoptosis in TUNEL staining, and the two-way ANOVA analysis shows that knockdown GRP94 had a significant (p &lt; 0.01) effect on the protein levels of Bcl-2 and Caspase-3. For CCK-8 assay, ERS had a significant inhibitory(p &lt; 0.05) effect on cell proliferation when treated with ERS for 24 h, and both knockdown GRP94 and ERS had a significant inhibitory(p &lt; 0.05) effect on cell proliferation when treated with ERS for 36 h and 48 h. We concluded that GRP94 can protect the cell from ERS-induced apoptosis by promoting the IGF-1 system and ubiquitin. These results provide valuable information on the adaptive mechanisms of the liver under ERS, and could help identify vital functional genes to be applied as possible diagnostic biomarkers and treatments for diseases induced by ERS in the future.

Effects of targeted-edited oncogenic insulin-like growth factor-1 receptor with specific-sgRNA on biological behaviors of HepG2 cells.

BACKGROUNDInsulin-like growth factor-1 receptor (IGF-1R) is over-expressed in hepatocellular carcinoma (HCC). However, the relationship between IGF-1R activation and HCC progression remains unidentified. AIMTo investigate the effects of editing IGF-1R on the biological features of HCC cells.METHODSImmunohistochemistry analyzed the expressions of IGF-1R and P-glyco protein (P-gp) in HCC tissues and their distal non-cancerous tissues (non-Ca). IGF-1R was edited with Crispr/Cas9 system, screened specific sgRNAs, and then transfected into HepG2 cells. CCK-8, scratch wound test detected cell proliferation, migration, invasion and transwell assays, respectively. Alterations of IGF-1R and P-gp were confirmed by Western blotting. Alterations of anti-cancer drug IC50 values were analyzed at the cell level. RESULTSThe positive rates of IGF-1R (93.6%, χ2 = 63.947) or P-gp (88.2%, χ2 = 58.448) were significantly higher (P < 0.001) in the HCC group than those (36.6% in IGF-1R or 26.9% in P-gp) in the non-Ca group. They were positively correlated between high IGF-1R and P-gp expression, and they were associated with hepatitis B virus infection and vascular invasion of HCC. Abnormal expressions of circulating IGF-1R and P-gp were confirmed and associated with HCC progression. Biological feature alterations of HCC cells transfected with specific sgRNA showed IGF-1R expression down-regulation, cell proliferation inhibition, cell invasion or migration potential decreasing, and enhancing susceptibility of HepG2 cells to anti-cancer drugs.CONCLUSIONEdited oncogenic IGF-1R was useful to inhibit biological behaviors of HepG2 cells.

The clinicopathological and prognostic significances of IGF-1R and Livin expression in patients with colorectal cancer

BackgroundColorectal cancer (CRC) is the third most common cancer worldwide. However, limited effective biomarkers are associated with the tumorigenesis and prognosis of CRC.MethodsThe present study identified potential signatures from The Cancer Genome Atlas (TCGA) database and further validated the identified biomarkers in CRC tissues by immunohistochemistry (IHC).ResultsThe expression of insulin-like growth factor 1 receptor (IGF-1R) and Livin gene was significantly upregulated in CRC samples compared to the adjacent normal samples in the TCGA dataset. IHC indicated that IGF-1R and Livin protein levels are increased in CRC and adenoma tissues compared to normal tissues. Notably, the IGF-1R protein levels differed significantly between adenoma and CRC. The elevated IGF-1R and Livin expression was associated with CRC clinicopathological features, including age, gender, histological subtype, individual cancer stages, nodal metastasis, and TP53-mutant in TCGA. Additionally, the IGF-1R promoter methylation level was closely related to CRC. Consistent with the TCGA study, IHC indicated that overexpressed IGF-1R and Livin proteins were independent risk factors for stage and metastasis. A marked correlation was established between IGF-1R and Livin expression in CRC, while the survival map showed no significant correlation with CRC. Kaplan–Meier survival curves showed that CRC patients with high IGF-1R or Livin expression had a prolonged overall disease-free survival than those with low expression in TCGA.ConclusionIGF-1R and Livin are associated with CRC tumorigenesis and might be valuable for novel biomarker identification and targeted therapeutic strategy development.

Leptin Promotes Primordial Follicle Activation by Regulating Ovarian Insulin-like Growth Factor System in Chicken.

Leptin and insulin-like growth factor 1 (IGF-1) regulate follicle development and reproduction in vertebrates. This study investigated the role played by leptin and IGF-1 in primordial follicle activation in the ovary of 7-day-old chicks. Different doses of leptin were intraperitoneally administrated to female layer chicks, and further analyses were performed. While leptin administration did not affect hepatic leptin receptor (LEPR), growth hormone receptor (GHR), or IGF-1, the lower dose of leptin significantly increased the messenger RNA (mRNA) expression of IGF-1, IGF-1 receptor, and IGF-binding protein (IGFBP)-2 and attenuated anti-Müllerian hormone (AMH) gene expression in the ovary. Furthermore, the ovaries of the same age chicks were challenged with leptin and/or IGF-1 in vitro. Leptin at a lower dose increased the mRNA expression of IGF-1, LEPR, and leptin; 100 ng/mL leptin and 10 ng/mL IGF-1 alone or combined with leptin reduced IGFBP-2 mRNA expression. AMH gene expression was also reduced by all doses except 10 ng/mL leptin. Histological studies showed that a lower dose of leptin injection induced the primordial follicle growth in the ovary in vivo, and the number of primordial follicles was higher in all leptin treatments over control in vitro. Moreover, the luciferase assay revealed that leptin enhanced IGF-1 promoter activity in LEPR-expressing CHO-K1 cells. Collectively, these results indicate that leptin directly affects the IGF-1/IGFBP system and promotes primordial follicular growth in the ovary of early posthatch chicks. In addition, the follicular development by leptin-induced IGF-1 is, at least in part, caused by the suppression of AMH in the ovary.

Research Note: Expression of IGF-1 and IGF-1 receptor proteins in skeletal muscle fiber types in chickens with hepatic fibrosis

We investigated the expression of insulin-like growth factor 1 (IGF-1) and IGF-1 type 1 receptor (IGF-1R) in skeletal muscle fiber types in chickens with hepatic fibrosis induced by bile duct ligation (BDL). Eleven hens, approximately 104 weeks old, were randomly assigned to BDL (n = 4) and sham surgery (SHAM; n = 7) groups. In BDL hens, histopathology revealed marked bile duct proliferation and liver fibrosis. The cross-sectional area (CSA) of myofibers from both the pectoralis (PCT) muscles significantly decreased in the BDL group compared with the SHAM group (P < 0.01). In contrast, the CSA of myofibers from the femorotibialis lateralis (FTL) muscle did not decrease in the BDL group. Type I fibers were large, round, and hypertrophic. Elongated type IIA and IIB fibers were also present. For IGF-1 immunostaining, the immunoreaction intensity was higher in the PCT in the BDL group than the SHAM group. Within the BDL group, type I fibers from FTL had a stronger immunoreaction intensity than the type II fibers. For IGF-1R immunostaining, the intensity of the immunoreactions was similar within the PCT in the BDL group compared with the SHAM group. For FTL, type I fibers had stronger reactions to IGF-1R than type II fibers in the BDL group. These results suggest that type I fibers express both IGF-1 and IGF-1R and become hypertrophic in chickens with hepatic fibrosis.

Circular RNA circ_0006089 regulates the IGF1R expression by targeting miR-143-3p to promote gastric cancer proliferation, migration and invasion

ABSTRACT Circular RNAs (circRNAs) figure prominently in regulating the progression of a variety of human malignancies. This study was performed to probe how circ_0006089 functioned in gastric cancer (GC). CircRNA expression profile GSE83521 was downloaded from Gene Expression Omnibus (GEO) database, and circRNAs and analyzed. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure circ_0006089, microRNA-143-3p (miR-143-3p) and insulin-like growth factor 1 receptor (IGF1R) mRNA expressions in GC tissues and cell lines. Kaplan-Meier curves were used to detect the relationship between circ_0006089 expression and overall survival time of GC patients. Cell counting kit-8 (CCK-8) and 5-bromo-2-deoxyuridine (BrdU) assays were employed to detect the proliferative ability of GC cells after circ_0006089 was overexpressed or knocked down. Wound healing assay and Transwell assay were executed to examine the migration and invasion ability of GC cells. Western blot was adopted to detect IGF1R protein expressions. Circ_0006089 expression was up-regulated in GC samples and cell lines. And high circ_0006089 expression was associated with shorter survival time in GC patients. Circ_0006089 overexpression in GC cells significantly accelerated GC cell proliferation, migration and invasion, whereas circ_0006089 knockdown resulted in the opposite effects. Additionally, miR-143-3p was validated as a downstream target of circ_0006089, and circ_0006089 could positively regulate IGF1R expression via repressing miR-143-3p. Circ_0006089 is highly expressed in GC, and it promotes the malignancy of GC cells via modulating miR-143-3p/IGF1R axis, suggesting that circ_0006089 may serve as a promising therapeutic target for GC.

Insulin Receptor Genetic Variants Causal Association with Type 2 Diabetes: A Mendelian Randomization Study

ABSTRACTBackgroundType 2 diabetes (T2D) is a prevalent chronic disease associated with several comorbidities.ObjectivesThis study investigated whether the risk of T2D varied with genetically predicted insulin (INS), insulin receptor (INS-R), or insulin-like growth factor 1 receptor (IGF-1R) using genetic variants in a Mendelian randomization (MR) study.MethodsA 2-sample MR study was conducted using summary statistics from 2 genome-wide association studies (GWASs). Genetic predictors of the exposures (INS, INS-R, and IGF-1R) were obtained from a publicly available proteomics GWAS of the INTERVAL randomized controlled trial of blood donation in the United Kingdom. For T2D, the study leveraged the DIAbetes Meta-ANalysis of Trans-Ethnic association studies (DIAMANTE) consortium. The estimated associations of INS, INS-R, and IGF-1R proteins with T2D were based on independent single nucleotide polymorphisms (SNPs) strongly (P < 5 × 10–6) predicting each exposure. These SNPs were applied to publicly available genetic associations with T2D from the DIAMANTE case (n = 74,124) and control (n = 824,006) study of people of European descent. SNP-specific Wald estimates were meta-analyzed using inverse variance weighting with multiplicative random effects. Sensitivity analysis was conducted using the weighted median (WM) and MR-Egger.ResultsINS-R (based on 13 SNPs) was associated with a lower risk of T2D (OR: 0.95 per effect size; 95% CI: 0.92, 0.98; P = 0.001), with similar estimates from the WM and MR-Egger. Insulin (8 SNPs) and IGF-1R (10 SNPs) were not associated with T2D. However, 1 of the SNPs for INS-R was from the ABO blood group gene.ConclusionsThis study is consistent with a causally protective association of the INS-R with T2D. INS-R in RBCs regulates glycolysis and thus may affect their functionality and integrity. However, a pleiotropic effect via the blood group ABO gene cannot be excluded. The INS-R may be a target for intervention by repurposing existing therapeutics or otherwise to reduce the risk of T2D.

Morphological and molecular effects of overexpressed GH on mice mammary gland

Growth Hormone (GH) plays crucial roles in mammary gland development and growth, and its upregulation has been associated with breast cancer promotion and/or progression. To ascertain how high GH levels could promote mammary tissue oncogenic transformation, morphological characteristics and the expression of receptors involved in mammary growth, development and cancer, and of mitogenic mediators were analyzed in the mammary gland of virgin adult transgenic mice that overexpress GH.Whole mounting and histologic analysis evidenced that transgenic mice exhibit increased epithelial ductal elongation and enlarged ducts along with deficient branching and reduced number of alveolar structures compared to wild type mice. The number of differentiated alveolar structures was diminished in transgenic mice while the amount of terminal end buds (TEBs) did not differ between both groups of mice. GH, insulin-like growth factor 1 (IGF1) and GH receptor mRNA levels were augmented in GH-overexpressing mice breast tissue, as well as IGF1 receptor protein content. However, GH receptor protein levels were decreased in transgenic mice. Fundamental receptors for breast growth and development like progesterone receptor and epidermal growth factor receptor were also increased in mammary tissue from transgenic animals. In turn, the levels of the proliferation marker Ki67, cFOS and Cyclin D1 were increased in GH-overexpressing mice, while cJUN expression was decreased and cMYC did not vary.In conclusion, prolonged exposure to high GH levels induces morphological and molecular alterations in the mammary gland that affects its normal development. While these effects would not be tumorigenic per se, they might predispose to oncogenic transformation.

+3179G/A Insulin-Like Growth Factor-1 Receptor Polymorphism: A Novel Susceptibility Contributor in Anti-Ro/SSA Positive Patients with Sjögren's Syndrome: Potential Clinical and Pathogenetic Implications.

Background: Alterations of the insulin-like growth factor (IGF) pathway along with genetic variations of the IGF1 receptor (IGF1R) gene have been linked to the development of systemic autoimmunity, possibly through apoptosis induction. This study aims to investigate whether genetic variations of the IGF1R contribute to Sjögren’s syndrome (SS) pathogenesis and explores potential functional implications. Methods: DNA extracted from whole peripheral blood derived from 277 primary SS patients, complicated or not by lymphoma, and 337 Healthy controls (HC) was genotyped for the rs2229765 IGF1R polymorphism using the RFLP-PCR assay. Gene expression of IGF1R and IGF1 isoforms, caspases 1, 4, and 5, and inflammasome components NLRP3, ASC, IL1β, IL18, IL33, IGFBP3, and IGFBP6 were quantitated by RT-PCR in total RNA extracted from minor salivary gland biopsies (MSGs) of 50 SS patients and 13 sicca controls (SCs). In addition, IGF1R immunohistochemical (IHC) expression was assessed in formalin-fixed, paraffin-embedded MSG tissue sections derived from 10 SS patients and 5 SCs. Results: The prevalence of the A/A genotype of the rs2229765 IGF1R polymorphism was significantly higher in the anti-Ro/SSA positive SS population compared to healthy controls (24.8% vs. 10.7%, p = 0.001). Moreover, IGF1Rs at both mRNA and protein levels were reduced in SS-derived MSGs compared to SCs and were negatively associated with caspase 1 transcripts. The latter were positively correlated with NLRP3, ASC, and IL1β at the salivary gland tissue level. IGF1R expression in peripheral blood was negatively correlated with ESR and IgG serum levels and positively correlated with urine-specific gravity values. Conclusions: The rs2229765 IGF1R variant confers increased susceptibility for seropositive primary SS. Dampened IGF1R mRNA and protein expression in salivary gland tissues could be related to increased apoptosis and subsequently to the activation of inflammasome pathways.

Abstract 749: Plasma insulin-like growth factor 1-related biomarkers and risk of lethal prostate cancer

Abstract Background Experimental and epidemiologic evidence supports the role of plasma IGF-1 and risk of prostate cancer. About 5% of IGF-1 circulates in a free or bioavailable form, and is only weakly correlated with total IGF-1; we hypothesized that higher levels of free IGF-1 would be associated with risk of lethal prostate cancer. Methods Lethal prostate cancer was defined as fatal prostate cancer plus metastatic prostate cancer. Non-lethal prostate cancer was defined as cases in which the men remained free of known metastases for at least eight years. Using prospectively collected samples in a nested design, we identified 434 lethal cases and 524 men with non-lethal prostate cancer in two prospective cohorts: the Physicians' Health Study (mean years of follow-up 33.2) and the Health Professionals Follow-up Study (mean years of follow-up 18.5). Circulating levels in prediagnostic plasma samples were assayed for IGF-1-related biomarkers, including free and total IGF-1, acid labile subunit (ALS), pregnancy-associated plasma protein A (PAPP-A, a protease that cleaves the IGF complex), intact IGF binding protein 4 (IGFBP-4), and total IGFBP-4, with risk of lethal prostate cancer. We estimated odds ratios (ORs) and corresponding 95% confidence intervals (CI) for the associations between IGF-1-related biomarkers (in quartiles) and lethal prostate cancer using unconditional logistic regression models adjusted for age, height, weight, and body mass index. Subgroup analyses were conducted by time from blood draw to diagnosis, and tumor biomarkers, ERG as a marker of the TMPRSS2:ERG fusion, phosphatase and tensin homolog (PTEN) loss, and IGF-1 receptor (IGF1R) protein expression. Results We observed no significant association between free IGF-1 and lethal prostate cancer (pooled adjusted OR for the highest versus lowest group 0.93, 95% CI 0.64 to 1.35) after adjusting for potential covariates. However, men in the highest quartile of PAPP-A levels had 43% higher odds of developing lethal prostate cancer (pooled adjusted OR 1.43, 95% CI 1.05 to 1.95) compared to men in the lowest three quartiles. The positive association between PAPP-A and lethal prostate cancer was present among men without PTEN loss, but not among those with (P for interaction = 0.002). There were no significant differences across the two cohorts (P for heterogeneity &amp;gt; 0.05 for all) and no significant associations were observed between other plasma biomarkers and lethal prostate cancer. Conclusions We found no significant association between free IGF-1 and lethal prostate cancer, but provide suggestive evidence that higher PAPP-A levels are associated with an increased risk of developing lethal prostate cancer. This observation merits testing in other cohorts. Citation Format: Chaoran Ma, Ye Wang, Lorelei A. Mucci, Meir J. Stampfer, Michael Pollak, Kathryn L. Penney. Plasma insulin-like growth factor 1-related biomarkers and risk of lethal prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 749.

Long non-coding RNA DUXAP8 promotes tumorigenesis by regulating IGF1R via miR-9-3p in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide with a low 5-year survival rate. Long non-coding RNA (lncRNA) double homeobox A pseudogene 8 (DUXAP8) is an oncogene and a potential biomarker in various tumors, such as ovarian, colorectal and non-small-cell lung cancer. However, the function and molecular mechanism underlying DUXAP8 in HCC progression is not completely understood. The expression of DUXAP8, microRNA (miR)-9-3p and insulin-like growth factor 1 receptor (IGF1R) in HCC tissues and cells was detected via reverse transcription-quantitative PCR. The expression levels of IGF1R and epithelial-mesenchymal transition-associated proteins (Snail, Slug, E-cadherin, N-cadherin and vimentin) were assessed via western blotting. The effects of DUXAP8, miR-9-3p and IGF1R on proliferation, migration and invasion were examined by conducting Cell Counting Kit-8 and Transwell assays, respectively. The interaction between miR-9-3p and DUXAP8 or IGF1R was predicted using StarBase or TargetScan, and further assessed using dual luciferase reporter and RNA immunoprecipitation assays. DUXAP8 and IGF1R were upregulated and miR-9-3p was downregulated in HCC tissues and cells compared with adjacent healthy tissues and a normal liver cell line, respectively. miR-9-3p overexpression decreased the protein expression level of IGF1R, and miR-9-3p knockdown enhanced the protein expression level of IGF1R in HCC cells compared with the corresponding control groups. Moreover, compared with the corresponding control groups, DUXAP8 knockdown and miR-9-3p overexpression increased E-cadherin protein expression levels, and decreased Snail, Slug, N-cadherin and vimentin protein expression levels. However, miR-9-3p inhibitor and IGF1R overexpression reversed DUXAP8 knockdown- and miR-9-3p overexpression-induced effects, respectively. In addition, compared with the corresponding control groups, DUXAP8 knockdown and miR-9-3p overexpression suppressed proliferation, migration and invasion, which was reversed by miR-9-3p inhibitor and IGF1R overexpression, respectively. Moreover, miR-9-3p as the target of DUXAP8 and IGF1R as the target of miR-9-3p were verified in HCC cells. lncRNA DUXAP8 contributed to HCC tumorigenesis via the miR-9-3p/IGF1R axis, providing a novel therapeutic approach for HCC diagnosis and treatment.

Placental Insulin/IGF-1 Signaling, PGC-1α, and Inflammatory Pathways Are Associated With Metabolic Outcomes at 4-6 Years of Age: The ECHO Healthy Start Cohort.

An adverse intrauterine environment is associated with the future risk of obesity and type 2 diabetes. Changes in placental function may underpin the intrauterine origins of adult disease, but longitudinal studies linking placental function with childhood outcomes are rare. Here, we determined the abundance and phosphorylation of protein intermediates involved in insulin signaling, inflammation, cortisol metabolism, protein glycosylation, and mitochondrial biogenesis in placental villus samples from healthy mothers from the Healthy Start cohort. Using MANOVA, we tested the association between placental proteins and offspring adiposity (fat mass percentage) at birth (n = 109) and infancy (4-6 months, n = 104), and adiposity, skinfold thickness, triglycerides, and insulin in children (4-6 years, n = 66). Placental IGF-1 receptor protein was positively associated with serum triglycerides in children. GSK3β phosphorylation at serine 9, a readout of insulin and growth factor signaling, and the ratio of phosphorylated to total JNK2 were both positively associated with midthigh skinfold thickness in children. Moreover, peroxisome proliferator-activated receptor γ coactivator (PGC)-1α abundance was positively associated with insulin in children. In conclusion, placental insulin/IGF-1 signaling, PGC-1α, and inflammation pathways were positively associated with metabolic outcomes in 4- to 6-year-old children, identifying a novel link between placental function and long-term metabolic outcomes.