Insulin-like growth factor 2 targets IGF1R signaling transduction to facilitate metastasis and imatinib resistance in gastrointestinal stromal tumors

BACKGROUND Gastrointestinal stromal tumors(GISTs)are typical gastrointestinal tract neoplasms.Imatinib is the first-line therapy for GIST patients.Drug resistance limits the long-term effectiveness of imatinib.The regulatory effect of insulin-like growth factor 2(IGF2)has been confirmed in various cancers and is related to resistance to chemotherapy and a worse prognosis.AIM To further investigate the mechanism of IGF2 specific to GISTs.METHODS IGF2 was screened and analyzed using Gene Expression Omnibus(GEO:GSE225819)data.After IGF2 knockdown or overexpression by transfection,the phenotypes(proliferation,migration,invasion,apoptosis)of GIST cells were characterized by cell counting kit 8,Transwell,and flow cytometry assays.We used western blotting to evaluate pathway-associated and epithelial-mesenchymal transition(EMT)-associated proteins.We injected transfected cells into nude mice to establish a tumor xenograft model and observed the occurrence and metastasis of GIST.RESULTS Data from the GEO indicated that IGF2 expression is high in GISTs,associated with liver metastasis,and closely related to drug resistance.GIST cells with high expression of IGF2 had increased proliferation and migration,invasiveness and EMT.Knockdown of IGF2 significantly inhibited those activities.In addition,OEIGF2 promoted GIST metastasis in vivo in nude mice.IGF2 activated IGF1R signaling in GIST cells,and IGF2/IGF1R-mediated glycolysis was required for GIST with liver metastasis.GIST cells with IGF2 knockdown were sensitive to imatinib treatment when IGF2 overexpression significantly raised imatinib resistance.Moreover,2-deoxy-D-glucose(a glycolysis inhibitor)treatment reversed IGF2 overexpressionmediated imatinib resistance in GISTs.CONCLUSION IGF2 targeting of IGF1R signaling inhibited metastasis and decreased imatinib resistance by driving glycolysis in GISTs.

Exosome-transported IncRNA H19 regulates insulin-like growth factor-1 via the H19/let-7a/insulin-like growth factor-1 receptor axis in ischemic stroke

LncRNA(long non-coding RNA) H19 is a transcript of the H19 gene that is expressed during embryogenesis.We previously discove red a role for circular lncRNA H19 in the onset and prognosis of cerebral ischemic stroke.In this study,we used serum from patients with ischemic stroke,and mouse and cell culture models to elucidate the roles of plasma and neuronal exosomes in the regulatory effect of lncRNA H19 on insulin-like growth factor-1 and its mechanism in ischemic stroke,using western blotting,quantitative real-time polymerase chain reaction,and enzyme-linked immunosorbent assays.Plasma exosomal IncRNA H19 was negatively associated with blood levels of insulin-like growth factor-1 in samples from patients with cerebral ischemic stroke.In a mouse model,levels of exosomal IncRNA H19 were positively correlated with plasma and cerebral lncRNA H19.In a cell co-culture model,we confirmed that IncRNA H19 was transported from neuro ns to astrocytes by exosomes to induce downregulation of insulin-like growth factor-1 through the H19/let-7 a/insulin-like growth factor-1 receptor axis.This study provides the first evidence for the transpo rtation of IncRNA H19 by exosomes and the relationship between IncRNA H19 and insulinlike growth factor-1.

PRaG 3.0 therapy for human epidermal growth factor receptor 2-positive metastatic pancreatic ductal adenocarcinoma:A case report

BACKGROUND Pancreatic ductal adenocarcinoma(PDAC)is a highly fatal disease with limited effective treatment especially after first-line chemotherapy.The human epidermal growth factor receptor 2(HER-2)immunohistochemistry(IHC)positive is associated with more aggressive clinical behavior and shorter overall survival in PDAC.CASE SUMMARY We present a case of multiple metastatic PDAC with IHC mismatch repair proficient but HER-2 IHC weakly positive at diagnosis that didn’t have tumor regression after first-line nab-paclitaxel plus gemcitabine and PD-1 inhibitor treatment.A novel combination therapy PRaG 3.0 of RC48(HER2-antibody-drug conjugate),radio-therapy,PD-1 inhibitor,granulocyte-macrophage colony-stimulating factor and interleukin-2 was then applied as second-line therapy and the patient had confirmed good partial response with progress-free-survival of 6.5 months and overall survival of 14.2 month.She had not developed any grade 2 or above treatment-related adverse events at any point.Percentage of peripheral CD8^(+) Temra and CD4^(+) Temra were increased during first two activation cycles of PRaG 3.0 treatment containing radiotherapy but deceased to the baseline during the maintenance cycles containing no radiotherapy.CONCLUSION PRaG 3.0 might be a novel strategy for HER2-positive metastatic PDAC patients who failed from previous first-line approach and even PD-1 immunotherapy but needs more data in prospective trials.

Efficacy and safety of dacomitinib as first-line treatment for advanced non-small cell lung cancer patients with epidermal growth factor receptor 21L858R mutation:A multicenter,case-series study in China

Objective:To provide real-world evidence for the application of first-line dacomitinib treatment for epidermal growth factor receptor(EGFR)21L858R mutant non-small cell lung cancer(NSCLC)patients in China and to explore the factors influencing the efficacy and safety.Methods:A longitudinal,consecutive case-series,multicenter study with mixed prospective and retrospective data was conducted.The primary endpoint was progression-free survival(PFS),and the secondary endpoints included duration of treatment(DOT),overall survival(OS),objective response rate(ORR),disease control rate(DCR)and safety.Results:A total of 155 EGFR 21L858R mutant patients treated with first-line dacomitinib were included.The median follow-up time for these patients was 20.4 months.Among 134 patients with evaluable lesions,the ORR was 70.9%and the DCR was 96.3%.The median PFS was 16.3[95%confidence interval(95%CI),13.7−18.9]months.Multivariate Cox regression analysis suggested that the baseline brain metastasis(BM)status[with vs.without BM:hazard ratio(HR),1.331;95%CI,0.720−2.458;P=0.361]and initial doses(45 mg vs.30 mg:HR,0.837;95%CI,0.427−1.641;P=0.604)did not significantly affect the median PFS.The median DOT was 21.0(95%CI,17.5−24.6)months and the median OS was not reached.Genetic tests were performed in 64 patients after progression,among whom 29(45.3%)patients developed the EGFR 20T790M mutation.In addition,among the 46 patients who discontinued dacomitinib treatment after progression,31(67.4%)patients received subsequent third-generation EGFR-tyrosine kinase inhibitors.The most common grade 3−4 adverse events were rash(10.4%),diarrhea(9.1%),stomatitis(7.1%)and paronychia(4.5%).The incidence of grade 3−4 rash was significantly higher in the 45 mg group than that in the 30 mg group(21.9%vs.7.5%,P=0.042).Conclusions:First-line dacomitinib treatment demonstrated promising efficacy and tolerable adverse events among EGFR 21L858R mutant NSCLC patients in China.

Inetetamab combined with S-1 and oxaliplatin as first-line treatment for human epidermal growth factor receptor 2-positive gastric cancer

BACKGROUND Patients with human epidermal growth factor receptor 2(HER2)-positive advanced gastric cancer have poor outcomes.Trastuzumab combined with chemotherapy is the first-line standard treatment for HER2-positive advanced gastric cancer.Inetetamab is a novel anti-HER2 drug,and its efficacy and safety in gastric cancer have not yet been reported.AIM To evaluate the efficacy and safety of the S-1 plus oxaliplatin(SOX)regimen combined with inetetamab as a first-line treatment for HER2-positive advanced gastric cancer.METHODS Thirty-eight patients with HER2-positive advanced gastric cancer or gastroeso-phageal junction adenocarcinoma were randomly divided into two groups:One group received inetetamab combined with the SOX regimen,and the other group received trastuzumab combined with the SOX regimen.After 4-6 cycles,patients with stable disease received maintenance therapy.The primary endpoints were progression-free survival(PFS)and overall survival(OS),and the secondary endpoints were the objective response rate,disease control rate,and adverse events(AEs).RESULTS Thirty-seven patients completed the trial,with 18 patients in the inetetamab group and 19 patients in the trastuzumab group.In the inetetamab group,the median PFS was 8.5 months,whereas it was 7.3 months in the trastuzumab group(P=0.046);this difference was significant.The median OS in the inetetamab group vs the trastuzumab group was 15.4 months vs 14.3 months(P=0.33),and the objective response rate was 50%vs 42%(P=0.63),respectively;these differences were not significant.Common AEs included leukopenia,thrombocytopenia,nausea,and vomiting.The incidence rates of grade≥3 AEs were 56%in the inetetamab group and 47%in the trastuzumab group(P=0.63),with no significant difference.CONCLUSION In the first-line treatment of HER2-positive advanced gastric cancer,inetetamab and trastuzumab showed comparable efficacy.The inetetamab group showed superior PFS,and both groups had good safety.

BIRC3 induces the phosphoinositide 3-kinase-Akt pathway activation to promote trastuzumab resistance in human epidermal growth factor receptor 2-positive gastric cancer

BACKGROUND Trastuzumab-targeted therapy is currently the standard of care for advanced human epidermal growth factor receptor 2(HER2)-positive gastric cancer.However,the emergence of resistance to trastuzumab poses significant challenges.AIM To identify the key genes associated with trastuzumab resistance.These results provide a basis for the development of interventions to address drug resistance and improve patient outcomes.METHODS High-throughput sequencing and bioinformatics were used to identify the differentially expressed pivotal gene BIRC3 and delineate its potential function and pathway regulation.Tumor samples were collected from patients with HER2-positive gastric cancer to evaluate the correlation between BIRC3 expression and trastuzumab resistance.We established gastric cancer cell lines with both highly expressed and suppressed levels of BIRC3,followed by comprehensive in vitro and in vivo experiments to confirm the involvement of BIRC3 in trastuzumab resistance and to elucidate its underlying mechanisms.RESULTS In patients with HER2-positive gastric cancer,there is a significant correlation between elevated BIRC3 expression in tumor tissues and higher T stage,tumor node metastasis stage,as well as poor overall survival and progressionfree survival.BIRC3 is highly expressed in trastuzumab-resistant gastric cancer cell lines,where it inhibits tumor cell apoptosis and enhances trastuzumab resistance by promoting the phosphorylation and activation of the phosphoinositide 3-kinase-Akt(PI3K-AKT)pathway in HER2-positive gastric cancer cells,both in vivo and in vitro.CONCLUSION This study revealed a robust association between high BIRC3 expression and an unfavorable prognosis in patients with HER2-positive gastric cancer.Thus,the high expression of BIRC3 stimulated PI3K-AKT phosphorylation and activation,stimulating the proliferation of HER2-positive tumor cells and suppressing apoptosis,ultimately leading to trastuzumab resistance.

Advances in targeted therapy for human epidermal growth factor receptor 2 positive in advanced gastric cancer

Emerging therapeutic methods represented by targeted therapy are effective supplements to traditional first-line chemoradiotherapy resistance.Human epidermal growth factor receptor 2(HER2)is one of the most important targets in targeted therapy for gastric cancer.Trastuzumab combined with chemotherapy has been used as the first-line treatment for advanced gastric cancer.The safety and efficacy of pertuzumab and margetuximab in the treatment of gastric cancer have been verified.However,monoclonal antibodies,due to their large molecular weight,inability to penetrate the blood-brain barrier,and drug resistance,lead to decreased therapeutic efficacy,so it is necessary to explore the efficacy of other HER2-targeting therapies in gastric cancer.Small-molecule tyrosine kinase inhibitors,such as lapatinib and pyrrotinib,have the advantages of small molecular weight,penetrating the blood-brain barrier and high oral bioavailability,and are expected to become the drugs of choice for perioperative treatment and neoadjuvant therapy of gastric cancer after validation by large-scale clinical trials in the future.Antibo-drug conjugate,such as T-DM1 and T-DXd,can overcome the resistance of monoclonal antibodies despite their different mechanisms of tumor killing,and are a supplement for the treatment of patients who have failed the treatment of monoclonal antibodies such as trastuzumab.Therefore,after more detailed stratification of gastric cancer patients,various gastric cancer drugs targeting HER2 are expected to play a more significant role.

Therapeutic strategies targeting the epidermal growth factor receptor signaling pathway in metastatic colorectal cancer

More than 1.9 million new colorectal cancer(CRC)cases and 935000 deaths were estimated to occur worldwide in 2020,representing about one in ten cancer cases and deaths.Overall,colorectal ranks third in incidence,but second in mortality.More than half of the patients are in advanced stages at diagnosis.Treatment options are complex because of the heterogeneity of the patient population,including different molecular subtypes.Treatments have included conventional fluorouracil-based chemotherapy,targeted therapy,immunotherapy,etc.In recent years,with the development of genetic testing technology,more and more targeted drugs have been applied to the treatment of CRC,which has further prolonged the survival of metastatic CRC patients.

Concomitant epidermal growth factor receptor mutation/c-ros oncogene 1 rearrangement in non-small cell lung cancer: A case report

BACKGROUND Epidermal growth factor receptor(EGFR)mutation and c-ros oncogene 1(ROS1)rearrangement are key genetic alterations and predictive tumor markers for non-small cell lung cancer(NSCLC)and are typically considered to be mutually exc-lusive.EGFR/ROS1 co-mutation is a rare event,and the standard treatment appr-oach for such cases is still equivocal.CASE SUMMARY Herein,we report the case of a 64-year-old woman diagnosed with lung adenocar-cinoma,with concomitant EGFR L858R mutation and ROS1 rearrangement.The patient received two cycles of chemotherapy after surgery,but the disease prog-ressed.Following 1-month treatment with gefitinib,the disease progressed again.However,after switching to crizotinib,the lesion became stable.Currently,crizotinib has been administered for over 53 months with a remarkable treatment effect.CONCLUSION The efficacy of EGFR tyrosine kinase inhibitors and crizotinib was vastly different in this NSCLC patient with EGFR/ROS1 co-mutation.This report will aid future treatment of such patients.

Human epidermal growth factor receptor 2 expression level and combined positive score can evaluate efficacy of advanced gastric cancer

BACKGROUND Although treatment options for gastric cancer(GC)continue to advance,the overall prognosis for patients with GC remains poor.At present,the predictors of treatment efficacy remain controversial except for high microsatellite instability.AIM To develop methods to identify groups of patients with GC who would benefit the most from receiving the combination of a programmed cell death protein 1(PD-1)inhibitor and chemotherapy.METHODS We acquired data from 63 patients with human epidermal growth factor receptor 2(HER2)-negative GC with a histological diagnosis of GC at the Cancer Hospital,Chinese Academy of Medical Sciences between November 2020 and October 2022.All of the patients screened received a PD-1 inhibitor combined with chemotherapy as the first-line treatment.RESULTS As of July 1,2023,the objective response rate was 61.9%,and the disease control rate was 96.8%.The median progression-free survival(mPFS)for all patients was 6.3 months.The median overall survival was not achieved.Survival analysis showed that patients with a combined positive score(CPS)≥1 exhibited an extended trend in progression-free survival(PFS)when compared to patients with a CPS of 0 after receiving a PD-1 inhibitor combined with oxaliplatin and tegafur as the first-line treatment.PFS exhibited a trend for prolongation as the expression level of HER2 increased.Based on PFS,we divided patients into two groups:A treatment group with excellent efficacy and a treatment group with poor efficacy.The mPFS of the excellent efficacy group was 8 months,with a mPFS of 9.1 months after excluding a cohort of patients who received interrupted therapy due to surgery.The mPFS was 4.5 months in patients in the group with poor efficacy who did not receive surgery.Using good/poor efficacy as the endpoint of our study,univariate analysis revealed that both CPS score(P=0.004)and HER2 expression level(P=0.015)were both factors that exerted significant influence on the efficacy of treatment the combination of a PD-1 inhibitor and chemotherapy in patients with advanced GC(AGC).Finally,multivariate analysis confirmed that CPS score was a significant influencing factor.CONCLUSION CPS score and HER2 expression both impacted the efficacy of immunotherapy combined with chemotherapy in AGC patients who were non-positive for HER2.

Neuroprotective effects of insulin-like growth factor-2 in 6-hydroxydopamine-induced cellular and mouse models of Parkinson’s disease

Skin-derived precursor Schwann cells have been reported to play a protective role in the central nervous system. The neuroprotective effects of skin-derived precursor Schwann cells may be attributable to the release of growth factors that nourish host cells. In this study, we first established a cellular model of Parkinson’s disease using 6-hydroxydopamine. When SH-SY5 Y cells were pretreated with conditioned medium from skin-derived precursor Schwann cells, their activity was greatly increased. The addition of insulin-like growth factor-2 neutralizing antibody markedly attenuated the neuroprotective effects of skin-derived precursor Schwann cells. We also found that insulin-like growth factor-2 levels in the peripheral blood were greatly increased in patients with Parkinson’s disease and in a mouse model of Parkinson’s disease. Next, we pretreated cell models of Parkinson’s disease with insulin-like growth factor-2 and administered insulin-like growth factor-2 intranasally to a mouse model of Parkinson’s disease induced by 6-hydroxydopamine and found that the level of tyrosine hydroxylase, a marker of dopamine neurons, was markedly restored, α-synuclein aggregation decreased, and insulin-like growth factor-2 receptor downregulation was alleviated. Finally, in vitro experiments showed that insulin-like growth factor-2 activated the phosphatidylinositol 3 kinase(PI3 K)/AKT pathway. These findings suggest that the neuroprotective effects of skin-derived precursor Schwann cells on the central nervous system were achieved through insulinlike growth factor-2, and that insulin-like growth factor-2 may play a neuroprotective role through the insulin-like growth factor-2 receptor/PI3 K/AKT pathway. Therefore, insulin-like growth factor-2 may be an useful target for Parkinson’s disease treatment.

Mendelian randomization provides evidence for a causal effect of serum insulin-like growth factor family concentration on risk of atrial fibrillation

BACKGROUND Atrial fibrillation(AF)is one of the most common persistent arrhythmias among adult cardiovascular diseases.It is important to identify potential risk factors for AF.Members of the insulin-like growth factor(IGF)family exert a variety of effects on various cell types in the context of the pathogenesis of cardiovascular diseases,and previous population-based studies indicate associations between IGF family members and AF.However,the causal effects of IGF family members in AF have not been evaluated.assess genetic relationships between IGF family members and AF.METHODS MR was performed based on genome-wide association study(GWAS)datasets,and concentration levels of 14 IGF family members were retrieved.An initial MR analysis was conducted to identify single nucleotide polymorphisms potentially associated with IGF serum concentrations.A GWAS meta-analysis including 60620 AF cases and 970216 control participants of European ancestry was then conducted to identify AF causal effects.Two-sample MR packages were used to perform MR analysis in R.MR-Egger,weighted median(WM),and inverse va-riance weighted(IVW)methods were used.RESULTS Core Tip:Due to the high prevalence of atrial fibrillation(AF),and adverse outcomes related to it,it is important to identify risk factors associated with development of the condition.Insulin-like growth factor(IGF)family members exert a variety of effects on various cell types in the context of the pathogenesis of cardiovascular diseases,and previous population-based studies indicate associations between IGF family members and AF.However,the causal effects of IGF family members in AF have not been evaluated.The results of the current study provide novel insights on the pathogenesis of AF,and implic-ations of serum IGF family member concentrations when assessing the risk of AF.The study generated evidence on the potential roles of developmental pathological effects in the pathogenesis of AF.Further observational and experimental studies are critically needed.

Tyrosine kinase of insulin-like growth factor receptor as target for novel treatment and prevention strategies of colorectal cancer

AIM： To investigate the antineoplastic potency of the novel insulin-like growth factor 1 receptor （IGF-1R） tyrosine kinase inhibitor （TKI） NVP-AEW541 in cell lines and primary cell cultures of human colorectal cancer （CRC）. METHODS： Cells of primary colorectal carcinomas were from 8 patients. Immunostaining and crystal violet staining were used for analysis of growth factor receptor protein expression and detection of cell number changes, respectively. Cytotoxicity was determined by measuring the release of the cytoplasmic enzyme lactate dehydrogenase （LDH）. The proportion of apoptotic cells was determined by quantifying the percentage of sub-G1 （hypodiploid） cells. Cell cycle status reflected by the DNA content of the nuclei was detected by flow cytometry. RESULTS： NVP-AEW541 dose-dependently inhibited the proliferation of colorectal carcinoma cell lines and primary cell cultures by inducing apoptosis and cell cycle arrest. Apoptosis was characterized by caspase-3 activation and nuclear degradation. Cell cycle was arrested at the G1/S checkpoint. The NVP-AEW541-mediated cell cycle-related signaling involved the inactivation of Akt and extracellular signal-regulated kinase （ERK） 1/2, the upregulation of the cyclin-dependent kinase inhibitors p21^waf1/CIP1 and p27^kjp1, and the downregulation of the cell cycle promoter cyclin D1. Moreover, BAX was upregulated during NVP-AEW541-induced apoptosis, whereas Bcl-2 was downregulated. Measurement of LDH release showed that the antineoplastic effect of NVP-AEW541 was not due to general cytotoxicity of the compound. However, augmented antineoplastic effects were observed in combination treatments of NVP-AEW541 with either 5-FU, or the EGFR-antibody cetuximab, or the HMG-CoA-reductase inhibitor fluvastatin. CONCLUSION： IGF-1R-TK inhibition is a promising novel approach for either monoor combination treatment strategies of colorectal carcinoma and even for CRC chemoprevention.

A candidate targeting molecule of insulin-like growth factor-Ⅰ receptor for gastrointestinal cancers

Advances in molecular research in cancer have brought new therapeutic strategies into clinical usage.One new group of targets is tyrosine kinase receptors,which can be treated by several strategies,including small molecule tyrosine kinase inhibitors(TKIs) and monoclonal antibodies(mAbs).Aberrant activation of growth factors/receptors and their signal pathways are required for malignant transformation and progression in gastrointestinal(GI) carcinomas.The concept of targeting specif ic carcinogenic receptors has been validated by successful clinical application of many new drugs.Type I insulin-like growth factor(IGF) receptor(IGF-IR) signaling potently stimulates tumor progression and cellular differentiation,and is a promising new molecular target in human malignancies.In this review,we focus on this promising therapeutic target,IGF-IR.The IGF/IGF-IR axis is an important modifier of tumor cell proliferation,survival,growth,and treatment sensitivity in many malignant diseases,including human GI cancers.Preclinical studies demonstrated that downregulation of IGF-IR signals reversed the neoplastic phenotype and sensitized cells to anticancer treatments.These results were mainly obtained through our strategy of adenoviruses expressing dominant negative IGF-IR(IGF-IR/dn) against gastrointestinal cancers,including esophagus,stomach,colon,and pancreas.We also summarize a variety of strategies to interrupt the IGFs/IGF-IR axis and their preclinical experiences.Several mAbs and TKIs targeting IGF-IR have entered clinical trials,and early results have suggested that these agents have generally acceptable safety profiles as single agents.We summarize the advantages and disadvantages of each strategy and discuss the merits/demerits of dual targeting of IGF-IR and other growth factor receptors,including Her2 and the insulin receptor,as well as other alternatives and possible drug combinations.Thus,IGF-IR might be a candidate for a molecular therapeutic target in human GI carcinomas.

Expression of insulin-like growth factor Ⅱ and its receptor in liver cells of chronic liver diseases

AIM To clarify the relationship between the Insulin like growth factor Ⅱ (IGF Ⅱ), IGF Ⅱ receptor and chronic liver diseases and to provide evidences for basic and clinical researches for exploring the potential mechanisms of human hepatocellular carcinoma (HCC). METHODS The poly (A)+ mRNA translation of IGF Ⅱ and IGF Ⅱ receptor in dysplasia liver cell (DLC n =10), liver cirrhosis (LC n =9) and chronic active hepatitis (CAH n =9) were analyzed with RNA gel electrophoresis, Northern blot and hybridization using human IGF Ⅱ and IGF Ⅱ receptor DNA probes labelled with 32 P through Nick translation and autoradiography. RESULTS The overexpression of IGF Ⅱ in DLC (10/10, 100%) was apparently higher than that in CAH (3/9, 33%) and LC (3/9, 33%), ( P <0 01). The overexpression of IGF Ⅱ receptor in DLC (7/10, 70%) was significantly higher than that in CAH (2/9, 22%) and LC (3/9, 33%), respectively. The data of HBV infection from different chronic liver diseases were analyzed. CONCLUSION The overexpression of IGF Ⅱ and IGF Ⅱ receptor in DLC was related to the preceeding of malignant phenotype of hepatocyte, which provided a diagnostic value for early detection of hepatocellular carcinoma (HCC). Persistent HBV infection is strongly associated with abnormal activation of IGF Ⅱ and IGF Ⅱ receptor, which might indicate a stimulating mechanism of autocrine or paracrine growth involved in live cell carcinogenesis.

Insulin-like growth factor-I receptor in proliferation and motility of pancreatic cancer

AIM:To develop a molecular therapy for pancreatic cancer, the insulin-like growth factor-I (IGF-I) signaling pathway was analyzed.METHODS: Pancreatic cancer cell lines (MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4) were cultured in media with 10 mL/L fetal bovine serum. Western blotting analysis was performed to clarify the expression of IGF-I receptor (IGF-IR). Picropodophyllin (PPP), a specific inhibitor of IGF-IR, LY294002, a specific inhibitor of phosphatidylinositol3 kinase (PI3K), and PD98059, a specific inhibitor of mitogen-activated protein kinase, were added to the media. After 72 h, a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt (MTS) assay was performed to analyze cell proliferation. A wound assay was performed to analyze cell motility with hematoxylin and eosin (HE) staining 48 h after addition of each inhibitor. RESULTS: All cell lines clearly expressed not only IGF-IR but also phosphorylated IGF-IR. PPP significantly suppressed proliferation of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 cells to 36.9% ± 2.4% (mean ± SD), 30.9% ± 5.5%, 23.8% ± 3.9%, 37.1% ± 5.3%, 10.4% ± 4.5%, 52.5% ± 4.5% and 22.6% ± 0.4%, at 2 μmol/L, respectively (P < 0.05). LY294002 significantly suppressed proliferation of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 cells to 44.4% ± 7.6%, 32.9% ± 8.2%, 53.9% ± 8.0%, 52.8% ± 4.0%, 32.3% ± 4.2%, 51.8% ± 4.5%, and 30.6% ± 9.4%, at 50 μmol/L, respectively (P < 0.05). PD98059 did not significantly suppress cell proliferation. PPP at 2 μmol/L suppressed motility of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 cells to 3.0% ± 0.2%, 0%, 0%, 2.0% ± 0.1%, 5.0% ± 0.2%, 3.0% ± 0.1%, and 5.0% ± 0.2%, respectively (P < 0.05). LY294002 at 50 μmol/L suppressed motility of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 to 3.0% ± 0.2%, 0%, 3.0% ± 0.2%, 0%, 0%, 0% and 3% ± 0.1%, respectively (P < 0.05). PD980509 at 20 μmol/L did not suppress motility. Cells were observed by microscopy to analyze the morphological changes induced by the inhibitors. Cells in medium treated with 2 μmol/L PPP or 50 μmol/L LY294002 had pyknotic nuclei, whereas those in medium with 20 μmol/L PD98059 did not show apoptosis.CONCLUSION: IGF-IR and PI3K are good candidates for molecular therapy of pancreatic cancer.

Expression of insulin-like growth factor Ⅱ and its receptor in hepatocellular carcinogenesis

INTRODUCTIONInsulin-like growth factor Ⅱ(IGF-Ⅱ) is a mitogenic peptide of 74 kD and is mostly synthesized in fetal liver tissue .IGF-Ⅱ is believed to play an important role in fetal growth and development and is involved in cellular proliferation and differentiation[1-5]. Recently ,several researchers have reported increased expression of the IGF-Ⅱgene in human hepatocellular carcinoma (HCC) and adjacent non-cancerous liver tissues [6-10].

Role of Insulin-like Growth Factor II Receptor in Transdifferentiation of Free Silica-induced Primary Rat Lung Fibroblasts

Objective To study the role of insulin-like growth factor II receptor in free silica-induced transdifferentiation of primary rat lung fibroblasts Methods Rat lung fibroblasts and rat alveolar macrophages were cultured. A transdifferentiation model of primary rat lung fibroblasts was induced by free silica. Levels of a-SMA protein, IGF-liR protein and mRNA were measured by immunocytochemistry, Western blot and RT-PCR, respectively. Lung fibroblasts were treated with Wortmannin. Results The expression levels of a-SMA concentration and decreased after Wortmann and IGF-IIR increased with the increasing free silica n was used. Conclusion The IGF-IIR plays an important role in free silica-induced transdifferentiation of primary rat lung fibroblasts.

Overexpression of insulin-like growth factor-Ⅰ receptor as a pertinent biomarker for hepatocytes malignant transformation

AIM: To investigate the dynamic features of insulin-like growth factor-I receptor (IGF-IR) expression in rat hepatocarcinogenesis, and the relationship between IGF-IR and hepatocytes malignant transformation at mRNA or protein level.METHODS: Hepatoma models were made by inducing with 2-fluorenylacetamide (2-FAA) on male Sprague-Dawley rats. Morphological changes of hepatocytes were observed by pathological Hematoxylin and eosin staining, the dynamic expressions of liver and serum IGF-IR were quantitatively analyzed by an enzyme-linked immunosorbent assay. The distribution of hepatic IGF-IR was located by immunohistochemistry. The fragments of IGF-IR gene were amplified by reverse transcription-polymerase chain reaction, and confirmed by sequencing.RESULTS: Rat hepatocytes after induced by 2-FAA were changed dynamically from granule-like degeneration, precancerous to hepatoma formation with the progressing increasing of hepatic mRNA or IGF-IR expression. The incidences of liver IGF-IR, IGF-IR mRNA, specific IGF-IR concentration (ng/mg wet liver), and serum IGF-IR level (ng/mL) were 0.0%, 0.0%, 0.63 ± 0.17, and 1.33 ± 0.47 in the control; 50.0%, 61.1%, 0.65 ± 0.2, and 1.51 ± 0.46 in the degeneration; 88.9%, 100%, 0.66 ± 0.14, and 1.92 ± 0.29 in the precancerosis; and 100%, 100%, 0.96 ± 0.09, and 2.43 ± 0.57 in the cancerous group, respectively. IGF-IR expression in the cancerous group was significantly higher (P < 0.01) than that in any of other groups at mRNA or protein level. The closely positive IGF-IR relationship was found between livers and sera (r = 0.91, t = 14.222, P < 0.01), respectively.CONCLUSION: IGF-IR expression may participate in rat hepatocarcinogenesis and its abnormality should be an early marker for hepatocytes malignant transformation.

Insulin-like growth factor receptor-1 overexpression is associated with poor response of rectal cancers to radiotherapy

AIM: To explore the potential correlation between insulin-like growth factor receptor-1 (IGF-1R) expression and rectal cancer radiosensitivity.