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.

Inetetamab combined with tegafur as second-line treatment for human epidermal growth factor receptor-2-positive gastric cancer: A case report

BACKGROUND Human epidermal growth factor receptor-2(HER-2)plays a vital role in tumor cell proliferation and metastasis.However,the prognosis of HER2-positive gastric cancer is poor.Inetetamab,a novel anti-HER2 targeting drug independently developed in China,exhibits more potent antibody-dependent cell-mediated cytotoxicity than trastuzumab,which is administered as the first-line treatment for HER2-positive gastric cancer in combination with chemotherapy.In this case,the efficacy and safety of inetetamab combined with tegafur was investigated as a second-line treatment for HER2-positive gastric cancer.CASE SUMMARY A 52-year-old male patient with HER2-positive gastric cancer presented with abdominal distension,poor appetite,and fatigue two years after receiving six cycles of oxaliplatin combined with tegafur as first-line treatment after surgery,followed by tegafur monotherapy for six months.The patient was diagnosed with postoperative recurrence of gastric adenocarcinoma.He received 17 cycles of a combination of inetetamab,an innovative domestically developed anti-HER2 monoclonal antibody,and tegafur chemotherapy as the second-line treatment(inetetamab 200 mg on day 1,every 3 wk combined with tegafur twice daily on days 1–14,every 3 wk).Evaluation of the efficacy of the second-line treatment revealed that the patient achieved a stable condition and progression-free survival of 17 months.He tolerated the treatment well without exhibiting any grade 3-4 adverse events.CONCLUSION Inetetamab combined with chemotherapy for the treatment of metastatic HER2-positive gastric cancer demonstrates significant survival benefits and acceptable safety.

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.

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.

Roles of fibroblast growth factors in the treatment of diabetes

Diabetes affects about 422 million people worldwide,causing 1.5 million deaths each year.However,the incidence of diabetes is increasing,including several types of diabetes.Type 1 diabetes(5%-10%of diabetic cases)and type 2 diabetes(90%-95%of diabetic cases)are the main types of diabetes in the clinic.Accumulating evidence shows that the fibroblast growth factor(FGF)family plays important roles in many metabolic disorders,including type 1 and type 2 diabetes.FGF consists of 23 family members(FGF-1-23)in humans.Here,we review current findings of FGFs in the treatment of diabetes and management of diabetic complications.Some FGFs(e.g.,FGF-15,FGF-19,and FGF-21)have been broadly investigated in preclinical studies for the diagnosis and treatment of diabetes,and their therapeutic roles in diabetes are currently under investigation in clinical trials.Overall,the roles of FGFs in diabetes and diabetic complications are involved in numerous processes.First,FGF intervention can prevent high-fat diet-induced obesity and insulin resistance and reduce the levels of fasting blood glucose and triglycerides by regulating lipolysis in adipose tissues and hepatic glucose production.Second,modulation of FGF expression can inhibit renal and cardiac fibrosis by regulating the expression of extracellular matrix components,promote diabetic wound healing process and bone repair,and inhibit cancer cell proliferation and migration.Finally,FGFs can regulate the activation of glucoseexcited neurons and the expression of thermogenic genes.

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.

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.

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.

Insulin-like growth factor 2 mRNA-binding protein 1 promotes cell proliferation via activation of AKT and is directly targeted by microRNA-494 in pancreatic cancer

BACKGROUND Studies have shown that insulin-like growth factor 2 mRNA-binding protein 1(IGF2BP1)plays critical roles in the genesis and development of human cancers.AIM To investigate the clinical significance and role of IGF2BP1 in pancreatic cancer.METHODS Expression levels of IGF2BP1 and microRNA-494(miR-494)were mined based on Gene Expression Omnibus datasets and validated in both clinical samples and cell lines by quantitative real-time polymerase chain reaction and Western blot.The relationship between IGF2BP1 expression and clinicopathological factors of pancreatic cancer patients was analyzed.The effect and mechanism of IGF2BP1 on pancreatic cancer cell proliferation were investigated in vitro and in vivo.Analyses were performed to explore underlying mechanisms of IGF2BP1 upregulation in pancreatic cancer and assays were carried out to verify the posttranscriptional regulation of IGF2BP1 by miR-494.RESULTS We found that IGF2BP1 was upregulated and associated with a poor prognosis in pancreatic cancer patients.We showed that downregulation of IGF2BP1 inhibited pancreatic cancer cell growth in vitro and in vivo via the AKT signaling pathway.Mechanistically,we showed that the frequent upregulation of IGF2BP1 was attributed to the downregulation of miR-494 expression in pancreatic cancer.Furthermore,we discovered that reexpression of miR-494 could partially abrogate the oncogenic role of IGF2BP1.CONCLUSION Our results revealed that upregulated IGF2BP1 promotes the proliferation of pancreatic cancer cells via the AKT signaling pathway and confirmed that the activation of IGF2BP1 is partly due to the silencing of miR-494.

Association of Insulin-like Growth Factors with Lung Development in Neonatal Rats

To explore the relationship between Insulin-like growth factor (IGF)- Ⅰ, -Ⅱ and lung development in neonatal rats. 80 timed pregnant Sprague-Dawley ( SD) rats were randomly divided into 4 groups (n=20): group A (Control group), group B (Dexamethasone (DEX) 1 group), group C (DEX 2 group), group D (retinoic acid (RA) group). 20 pregnant rats in group A, B and D were injected subcutaneously or intraperitoneally with vehicle (NS), DEX, or RA respectively during gestational day 16 to 18. All newborn rats in group C were subcutaneously injected with DEX at day 1 to 3 after birth. The lung tissue was obtained at the following times: fetuses at gestational ages of 18, 20 and 21 days, and 1, 3, 5, 7, 10, 14 and 21 days after birth. Lung tissues were used for histopathological study, the polypeptides analysis of IGF-Ⅰ, -Ⅱ (immunohistochemistry and Western blot) and mRNA analysis ( RT- PCR). The results showed that the strongest expression of IGF-Ⅰ in group A and D occurred at ages of 5-7 days (alveolar stage). The stronger their expressions, the better the alveolar develop. The peak stage of expression in group B occurred earlier, on the day 3 after birth. Compared with group A, the expression of IGF-Ⅰ during gestation age of 18 days to age of 3 days in group B were significantly higher (P<0.01), but significantly lower at other time points (P<0.01). The expression of IGF-Ⅰ was lower in group C all the time and always higher in group D than those in group A (P<0.01). The peak expression of IGF-Ⅱ took place at the gestation age of 18 days, then gradually dropped to trace. During 18 days of gestation to age of 3 days, the expression of IGF-Ⅱ in group B was significantly higher than that in group A (P<0.01). No difference was found among all other groups. The change in the expression of IGF-Ⅰ, -Ⅱ mRNA in all 4 groups was similar to that of their polypeptides. The results suggested that there is a close linking between IGF-Ⅰ, -Ⅱ and lung development in newborns. The IGF-Ⅱ works at early stage and the that of IGF-Ⅰ works at the stage of new septa formation and alveoli maturation. The stronger their expressions, the more mature the lung development.

Changes of Serum Insulin-like Growth Factor-2 Response to Negative Symptom Improvements in Schizophrenia Patients Treated with Atypical Antipsychotics

Accumulating evidence suggests that a disruption of early brain development,in which insulin-like growth factor-2(IGF-2)has a crucial role,may underlie the pathophysiology of schizophrenia.Our previous study has shown that decreased serum IGF-2 was correlated with the severity of psychopathology in patients with schizophrenia.Here we conducted a prospective observation trial to investigate the effects of atypical antipsychotics on serum IGF-2 level and its relationship with clinical improvements in schizophrenia patients.Thirty-one schizophrenia patients with acute exacerbation and 30 healthy individuals were recruited in this study.Psychiatric symptoms were assessed using the Positive and Negative Syndrome Scale(PANSS)and serum IGF-2 levels were determined using ELISA.We found that schizophrenia patients with acute exacerbation had lower serum IGF-2 levels than control individuals at baseline(P<0.05).After 2 months of atypical antipsychotic treatment,a significant improvement in each PANSS subscore and total score was observed in patients(all P<0.01),and the serum IGF-2 levels of patients were significantly increased compared with those at baseline(203.13±64.62 vs.426.99±124.26 ng/mL;t=−5.044,P<0.001).Correlation analysis revealed that the changes of serum IGF-2 levels in patients were significantly correlated with the improvements of negative symptoms(r=−0.522,P=0.006).Collectively,our findings demonstrated changes of serum IGF-2 response to improvements of negative symptoms in schizophrenia patients treated with atypical antipsychotics,suggesting that serum IGF-2 might be a treatment biomarker for schizophrenia.

Variation in Expression of Insulin-like Growth Factors( IGFs) System Genes in Ovarian and Uterine Tissues of Aging Rats

Variations in expression of insulin-like growth factors （IGFs） system genes in rat ovarian and uterine tissues were investigated by real-time quantitative PCR amplification using RT2 ProfilerTM PCR Array Rat Insulin Signaling Pathway （PARN-030A） chips. According to results of gene detection, a total of 15 differeutially expressed genes were screened in ovarian tissues, including 3 upregulated genes and 10 downregulated genes; a total of 22 differentially expressed genes were screened in uterine tissues, including 5 upregulated genes and 17 downregulated genes. These differentially expressed genes might be related to the insulin resistance.

A predictive score for retinopathy of prematurity by using clinical risk factors and serum insulin-like growth factor-1 levels

AIM：To detect the impact of insulin-like growth factor-1（IGF-1）and other risk factors for the early prediction of retinopathy of prematurity（ROP）and to establish a scoring system for ROP prediction by using clinical criteria and serum IGF-1 levels.METHODS：The study was conducted with 127 preterm infants.IGF-1 levels in the 1st day of life,1st,2nd,3rd and4th week of life was analyzed.The score was established after logistic regression analysis,considering the impact of each variable on the occurrences of any stage ROP.A validation cohort containing 107 preterm infants was included in the study and the predictive ability of ROP score was calculated.RESULTS：Birth weights（BW）,gestational weeks（GW）and the prevalence of breast milk consumption were lower,respiratory distress syndrome（RDS）,bronchopulmonarydysplasia（BPD）and necrotizing enterocolitis（NEC）were more frequent,the duration of mechanical ventilation and oxygen supplementation was longer in patients with ROP（P〈0.05）.Initial serum IGF-1 levels tended to be lower in newborns who developed ROP.Logistic regression analysis revealed that low BW（〈1250 g）,presence of intraventricular hemorrhage（IVH）and formula feeding increased the risk of ROP.Afterwards,the scoring system was validated on 107 infants.The negative predictive values of a score less than 4 were 84.3%,74.7%and 79.8%while positive predictive values were 76.3%,65.5%and71.6%respectively.CONCLUSION：In addition to BW〈1250 g and IVH,formula consumption was detected as a risk factor for the development of ROP.Breastfeeding is important for prevention of ROP in preterm infants.

Liver insulin-like growth factor 2 methylation in hepatitis C virus cirrhosis and further occurrence of hepatocellular carcinoma

AIM: To assess the predictive value of the insulinlike growth factor 2 (Igf2) methylation profile for the occurrence of Hepatocellular Carcinoma (HCC) in hepatitis C (HCV) cirrhosis. METHODS: Patients with: (1) biopsy-proven compensated HCV cirrhosis; (2) available baseline frozen liver sample; (3) absence of detectable HCC; (4) regular screening for HCC; (5) informed consent for genetic analysis were studied. After DNA extraction from liver samples and bisulfite treatment, unbiased PCR and DHPLC analysis were performed for methylation analysis at the Igf2 locus. The predictive value of the Igf2 methylation profile for HCC wasassessed by Kaplan-Meier and Cox methods. RESULTS: Among 94 included patients, 20 developed an HCC during follow-up (6.9 ± 3.2 years). The methylation profile was hypomethylated, intermediate and hypermethylated in 13, 64 and 17 cases, respectively. In univariate analysis, two baseline parameters were associated with the occurrence of HCC: age (P = 0.01) and prothrombin (P = 0.04). The test of linear tendency between the three ordered levels of Igf2 methylation and probability of HCC occurrence was significant (Log Rank, P = 0.043; Breslow, P = 0.037; Tarone-Ware, P = 0.039). CONCLUSION: These results suggest that hypomethylation at the Igf2 locus in the liver could be predictive for HCC occurrence in HCV cirrhosis.

Glycosylation-independent binding to extracellular domains 11-13 of mannose-6-phosphate/insulin-like growth factor-2 receptor mediates the effects of soluble CREG on the phenotypic proliferation of vascular smooth muscle cells

Background The present study aimed to investigate the detailed mode and specific sites for their binding as well as the functional relevance of this binding in the phenotypic proliferation of vascular smooth muscle cells(SMCs). Methods CREG knocked-down SMCs were employed to evaluate the biological activity of wtCREG and mCREG.Expressions of SMC differentiation markers SM myosin heavy chain(SM-MHC),SM-actin,heavy caldesmon and myocardin were determined by Western blotting using specific antibodies. Cellular growth of SMCs was assessed by bromide dewuridine (BrdU) incorporation and cell cycle analysis on fluorescence-activated cell sorting(FACS).A solid-phase binding assay was used to study the binding of CREG to extracellular domains of M6P/IGF2R.The cellular co-localization of the two recombinant CREGs with M6P/IGF2R was detected on SMC surface by immunoprecipitation and immunofluorescence analysis.Results The molecular weight of wtCREG was around 30 kD while that of the mCREG was～25 kD.Treatment of wtCREG with PNGase F reduced its molecular weight from～30 kD to～25 kD,whereas PNGase F treatment had no effect on the molecular weight of mCREG.Both wtCREG and mCREG proteins enhanced SMC differentiation,inhibited BrdU incorporation,and arrested cell cycle progression when added to the culture medium.In CREG knocked-down SMCs,the amount of CREG detected by immunoblotting in M6P/IGF2R immunoprecipitates was significantly reduced when compared to normal cells.Both recombinant CREGs co-immunoprecipitated with M6P/IGF2R, although slightly reduced amount of the mutant CREG was detected in M6P/IGF2R immunoprecipitates.Immunostaining revealed that His-tagged CREGs co-localized with IGF2R on the cell surface in a glycosylation-independent manner.In vitro binding assay showed that CREGs bound to M6P/ IGF2R extracellular domains 7-10 and 11-13 in a glycosylation -dependent and -independent manner,respectively.Further blocking experiments using soluble M6P/IGF2R fragments and M6P/IGF2R neutralizing antibody indicated that the biological activities of recombinant CREGs in SMC growth and the up-regulation of SMC differentiation markers were all abolished by treatment with the M6P/IGF2R neutralizing antibody. However,although the growth inhibitory effect of wtCREG was nearly abolished by D7-10 or D11-13,the effect of mCREG was only reversed by Dll-13,indicating that the binding to domains 11-13 is required for CREG to modulate the proliferation of SMCs.Conclusions These data suggest that solubleCREG proteins can exert their biological function via binding to the extracellular domains 7-10 and 11-13 of cell surface M6P/IGF2R in both a glycosylation-dependent and -independent manner.

RNA interference affects tumorigenicity and expression of insulin-like growth factor-1,insulin-like growth factor-1 receptor,and basic fibroblast growth factor-2 in rat C6 glioma cells

BACKGROUND： Human gliomas are more likely to express basic fibroblast growth factor-2 （FGF-2） insulin-like growth factor-1（IGF-1）, and IGF-1 receptor （IGF-1R） than normal brain tissue. These factors activate signal transduction systems of Ras/MAPK and PI3K/Akl, which promote glioma growth. OBJECTIVE： To utilize RNA interference （RNAi） technique to down-regulate FGF-2, IGF-1, and IGF-1R gene expression, and to investigate the effects of these genes on rat C6 glioma cells, as well as the feasibility of RNAi for treating glioma. DESIGN, TIME AND SETTING： This neurooncological, randomized, controlled, in vivo and in vitro experiment, which used RNAi methodology, was performed at the Laboratory of Molecular Biology, Institute of Biochemistry, Chinese Academy of Sciences between August 2005 and February 2008. MATERIALS： Rat C6 cell lines were purchased from Shanghai Institute of Cellular Biology Affiliated to Chinese Academy of Sciences. Small interfering RNA （siRNA） was synthesized by Shanghai GenePharma. Anti-IGF-1, anti-IGF-1R, anti-FGF-2, anti-mouse and anti-rabbit IgG G1-HRP antibodies were provided by Santa Cruz Biotechnology, USA. Four to six week-old BALB/c nude mice were purchased from the Laboratory Animal Center, Chinese Academy of Sciences. METHODS： C6 glioma cells were transfected with siRNA, which was chemically synthesized in vitro to correspond to endogenous FGF-2, IGF-1, and IGF-1R genes. The inhibition ratio of targeting mRNA expression was detected by semiquantitative RT-PCR, and protein expression was determined by Western blot analysis. C6 glioma cell proliferation was observed using a growth curve C6 glioma cell apoptosis rate and cell cycle were detected by flow cytometry. C6 glioma cell growth regression was observed by transwell migration assay. In addition, nude mouse subcutaneous tumor models were used in this study. For studying the anti-tumor effects of IGF-1 and IGF-1R siRNA, two blank control groups, with six mice each, were set up： A （2.5 μg siRNA was injected one week after C6 cells were inoculated, Le., when tumor volume reached 8 mm × 8 mm） and B （siRNA was injected at the same time with C6 cells were inoculated. To study the effects of FGF-2 siRNA, the groups consisted of a blank control group, negative control group, 2.6 μg siRNA group, 4 μg siRNA group, and 5.3 μg siRNA group, with six mice each. MAIN OUTCOME MEASURES： mRNA and protein inhibition ratio of FGF-2, IGF-1, and IGF-1 R; C6 glioma cell proliferation, apoptosis, and cycle growth arrest; C6 glioma cell growth regression and subcutaneous tumorigenicity rates. RESULTS： All siRNA constructs proved to be effective. After 48 hours, transfection of 200 nmol/L siRNA resulted in a FGF-2 or IGF-1R gene inhibition ratio 〉 80% and an IGF-1 gene inhibition ratio of approximately 70%. Protein expression levels for FGF-2, IGF-1, and IGF-1R decreased in a dose-dependent manner following siRNA transfection, with an inhibition rate 〉 85%, 60%, and 50%, respectively. C6 glioma cell proliferation and apoptosis rates increased in proportion to siRNA. The apoptosis rate of C6 glioma cells induced by FGF-2, IGF-1, and IGF-1R siRNA was 39.96%, 15.07% and 22.47%, respectively （P 〈 0.01）. Transfection of 200 nmol/L IGF or IGF-1R siRNA for 48 hours suppressed C6 glioma cell migration. At 30 days after intratumoral injection of 2.6, 4, and 5.3 tJg FGF-2 siRNA, tumor growth regression rate of FGF-2 siRNA was 56%, 67%, and 86%, respectively. The tumor growth regression rate was 71.88% and 45.71%, respectively, when IGF-1 or IGF-1R siRNA was intratumorally injected 1 week after C6 glioma cell transplantation. When IGF-1 or IGF-1 R siRNA was intratumorally injected during C6 glioma cell transplantation, the tumor growth regression rate was 78.13% and 74.29%, respectively. CONCLUSION： siRNA transfection downregulated gene expression of FGF-2, IGF-1, and IGF-1R In addition, siRNA treatment markedly suppressed glioma cell proliferation, growth, and migration, and concomitantly reduced subcutaneous tumorigenicity.

A peptide containing the receptor binding site of insulin-like growth factor binding protein-2 enhances bone mass in ovariectomized rats

Male Igfbp2-/-mice have a significant reduction in bone mass and administration of a peptide that contains the insulin-like growth factor binding protein-2(IGFBP-2) receptor-binding domain stimulates bone formation in these animals. Female Igfbp2-/-mice do not have this phenotype but following ovariectomy(OVX) lose more bone than OVX wild-type mice. This suggests that in the absence of estrogen, IGFBP-2 is required to maintain bone mass. Therefore these studies were undertaken to determine if this peptide could stimulate bone acquisition in OVX rats. OVX rats were divided into seven treatment groups: sham animals, OVX animals, OVX animals receiving a control scrambled peptide, or one of three doses of the active peptide termed PEG-HBD-1(0.7, 2,and 6 mg·kg^(-1)) and an OVX group receiving parathyroid hormone(PTH)(50 μg·kg-1 per day). The peptides were administered for8 weeks. DXA revealed a significant reduction in femoral and tibial areal bone mineral density(aBMD) after OVX, whereas treatment with the high-dose peptide increased aBMD by 6.2% ± 2.4%(P < 0.01) compared to control peptide; similar to the increase noted with PTH(5.6% ± 3.0%, P < 0.01). Similar increases were noted with two lower doses of the peptide(3.8% ± 1.5%, P < 0.05 for low dose; 3.1% ± 1.6%, P = 0.07 for middle dose). Micro CT showed that the OVX control peptide animals had reductions of 41% and64% in femoral trabecular BV/TV and trabecular number, respectively. All three doses of the peptide increased bone volume/total volume(BV/TV) significantly, while the low and middle doses increased trabecular number. Cortical BV/TV and thickness at the midshaft increased significantly with each dose of peptide(18.9% ± 9.8%, P < 0.01 and 14.2% ± 7.9%, P < 0.01 for low dose; 23.7% ±10.7%, P < 0.001 and 15.8% ± 6.1%, P < 0.001 for middle dose; 19.0% ± 6.9%, P < 0.01 and 16.2% ± 9.7%, P < 0.001 for high dose)and with PTH(25.8% ± 9.2%, P < 0.001 and 19.4% ± 8.8%, P < 0.001). Histomorphometry showed that the lowest dose of peptide stimulated BV/TV, trabecular thickness, mineral apposition rate(MAR), bone formation rate/bone surface(BFR/BS), number of osteoblasts/bone perimeter(N.ob/B.pm), and decreased osteoclast surface/bone perimeter(Oc.S/B.Pm). The highest dose stimulated each of these parameters except MAR and BFR/BS. Thus, the heparin-binding domain receptor region of IGFBP-2 accounts for its anabolic activity in bone. Importantly, this peptide enhances bone mass in estrogen-deficient animals.

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.

Depletion of gut microbiota facilitates fibroblast growth factor 21-mediated protection against acute pancreatitis in diabetic mice

BACKGROUND Fibroblast growth factor 21(FGF21),primarily secreted by the pancreas,liver,and adipose tissues,plays a pivotal role in regulating glucose and lipid metabolism.Acute pancreatitis(AP)is a common inflammatory disease with specific clinical manifestations.Many patients with diabetes present with concurrent inflammatory symptoms.Diabetes exacerbates intestinal permeability and intestinal inflammation,thus leading to the progression to AP.Our previous study indicated that FGF21 significantly attenuated susceptibility to AP in mice.AIM To investigate the potential protective role of FGF21 against AP in diabetic mice.METHODS In the present study,a mouse model of AP was established in diabetic(db)/db diabetic mice through ceruletide injections.Thereafter,the protective effects of recombinant FGF21 protein against AP were evaluated,with an emphasis on examining serum amylase(AMS)levels and pancreatic and intestinal inflammatory cytokines[interleukin(IL)-6,tumor necrosis factor-alpha(TNF-),and intestinal IL-1β].Additionally,the impact of this treatment on the histopathologic changes of the pancreas and small intestinal was examined to elucidate the role of FGF21 in diabetic mice with AP.An antibiotic(Abx)cocktail was administered in combination with FGF21 therapy to investigate whether the effect of FGF21 on AP in diabetic mice with AP was mediated through the modulation of the gut microbiota. Subsequently, thePhylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt), a bioinformaticssoftware package, was used to predict different pathways between the groups and to explore the potentialmechanisms by which the gut microbiota influenced the protective effect of FGF21.RESULTSThe results indicated that FGF21 notably diminished the levels of serum AMS (944.5 ± 15.9 vs 1732 ± 83.9, P < 0.01)and inflammatory factors including IL-6 (0.2400 ± 0.55 vs 1.233 ± 0.053, P < 0.01), TNF- (0.7067 ± 0.22 vs 1.433 ±0.051, P < 0.01), and IL-1β (1.377 ± 0.069 vs 0.3328 ± 0.02542, P < 0.01) in diabetic mice with AP. Moreover, notablesigns of recovery were observed in the pancreatic structure of the mice. The histologic evidence of inflammation inthe small intestine, including edema and villous damage, was significantly alleviated. FGF21 also significantlyaltered the composition of the gut microbiota, reestablishing the Bacteroidetes/Firmicutes ratio. Upon treatment withan Abx cocktail to deplete the gut microbiota, the FGF21 + Abx group showed lower levels of serum AMS (0.9328 ±0.075 vs 0.2249 ± 0.023, P < 0.01) and inflammatory factors (1.083 ± 0.12 vs 0.2799 ± 0.032, p < 0.01) than the FGF21group. Furthermore, the FGF21 + Abx group exhibited diminished injury to the pancreatic and small intestinaltissues, accompanied by a significant decrease in blood glucose levels (17.50 ± 1.1 vs 9.817 ± 0.69 mmol/L, P <0.001). These findings underscored the superior protective effects of the combination therapy involving an Abxcocktail with FGF21 over the FGF21 treatment alone in diabetic mice with AP. The gut microbiota compositionacross different groups was further characterized, and a differential expression analysis of gene functions wasundertaken using the PICRUSt2 prediction method. These findings suggested that FGF21 could potentially confertherapeutic effects on diabetic mice with AP by modulating the sulfate reduction I pathway and the superpathwayof n-acetylceramide degradation in the gut microbiota.CONCLUSION This study reveals the potential of FGF21 in improving pancreatic and intestinal damage recovery, reducing bloodglucose levels, and reshaping gut microbiota composition in diabetic mice with AP. Notably, the protective effectsof FGF21 are augmented when combined with the Abx cocktail.

Tyrosine kinase inhibitors and human epidermal growth factor receptor-2 positive breast cancer

The body of evidence investigating human epidermal growth factor receptor-2(HER2)directed therapy in patients with breast cancer(BC)has been growing within the last decade.Recently,the use of tyrosine kinase inhibitors(TKIs)has been of particular interest in the treatment of human malignancies.This literature commentary is intended to highlight the most recent findings associated with the widely-studied TKI agents and their clinical significance in improving the outcomes of HER2 positive BC.