Expression of IGF-I, IGF-II, and IGF-IR in gallbladder carcinoma. A systematic analysis including primary and corresponding metastatic tumours

Next generation sequencing uncovers multiple miRNAs associated molecular targets in gallbladder cancer patients

Gallbladder cancer (GBC) is a lethal disease with surgical resection as the only curative treatment. However, many patients are ineligible for surgery, and current adjuvant treatments exhibit limited effectiveness. Next-generation sequencing has improved our understanding of molecular pathways in cancer, sparking interest in microRNA-based gene regulation. The aim of the study is to identify dysregulated miRNAs in GBC and investigate their potential as therapeutic tools for effective and targeted treatment strategies. GBC and control tissue samples were sequenced for miRNA expression using the Illumina HiSeq platform. Biological processes and related pathways were determined using the Panther and Gene Ontology databases. 439 significantly differentially expressed miRNAs were identified; 19 of them were upregulated and 29 were downregulated. Key enriched biological processes included immune cell apoptosis, endoplasmic reticulum (ER) overload response, and negative regulation of the androgen receptor (AR) signaling pathway. Panther analysis revealed the insulin-like growth factor (IGF)-mitogen activated protein kinases (MAPK) cascade, p38 MAPK pathway, p53 pathway, and FAS (a subgroup of the tumor necrosis factor receptor) signaling pathway as highly enriched among dysregulated miRNAs. Kirsten rat sarcoma virus (KRAS), AR, and interferon gamma (IFN-γ) pathways were identified among the key pathways potentially amenable to targeted therapy. We concluded that a combination approach involving miRNA-based interventions could enhance therapeutic outcomes. Our research emphasizes the importance of precision medicine, targeting pathways using sense and anti-sense miRNAs as potential therapies in GBC.

Patient-derived organoids for personalized gallbladder cancer modelling and drug screening

BACKGROUND

Gallbladder carcinoma (GBC) is a relatively rare but highly aggressive cancer with late clinical detection and a poor prognosis. However, the lack of models with features consistent with human gallbladder tumours has hindered progress in pathogenic mechanisms and therapies.

METHODS

We established organoid lines derived from human GBC as well as normal gallbladder and benign gallbladder adenoma (GBA) tissues. The histopathology signatures of organoid cultures were identified by H&E staining, immunohistochemistry and immunofluorescence. The genetic and transcriptional features of organoids were analysed by whole-exome sequencing and RNA sequencing. A set of compounds targeting the most active signalling pathways in GBCs were screened for their ability to suppress GBC organoids. The antitumour effects of candidate compounds, CUDC-101 and CUDC-907, were evaluated in vitro and in vivo.

RESULTS

The established organoids were cultured stably for more than 6 months and closely recapitulated the histopathology, genetic and transcriptional features, and intratumour heterogeneity of the primary tissues at the single-cell level. Notably, expression profiling analysis of the organoids revealed a set of genes that varied across the three subtypes and thus may participate in the malignant progression of gallbladder diseases. More importantly, we found that the dual PI3K/HDAC inhibitor CUDC-907 significantly restrained the growth of various GBC organoids with minimal toxicity to normal gallbladder organoids.

CONCLUSIONS

Patient-derived organoids are potentially a useful platform to explore molecular pathogenesis of gallbladder tumours and discover personalized drugs.

Insulin-Like Growth Factor-1 Receptor Targeted Fluorescent Imaging for Gallbladder Cancer in Orthotopic Mouse Models

Background/Aims

Gallbladder cancer is fatal, but fluorescent imaging technology can facilitate timely diagnosis and improve patient outcomes. Fluorophore-conjugated insulin-like growth factor-1 receptor (IGF-1R) targeted antibodies were used to visualize gallbladder cancer in orthotopic tumor mouse models.

Methods

Western blotting, flow cytometric analysis, and confocal microscopy detected the expression of IGF-1R in SNU-308, SNU-478, and SNU-1196 bile duct cancer cells. In vivo imaging of SNU-478 and SNU-1196 subcutaneous tumors and orthotopic gallbladder tumor models of SNU-478 were performed after injection with DyLight 650-conjugated IGF-1R antibody.

Results

Western blotting and flow cytometric analysis showed that IGF-1R was expressed in bile duct cancer cells, and confocal microscopy demonstrated that IGF-1R antibody was able to bind to IGF-1R on the cell membrane. Fluorescent IGF-1R antibody injected into the mouse tail vein made subcutaneous tumors and orthotopic tumors become fluorescent. The intensity of fluorescence from the tumor was stronger than that from surrounding normal tissues. Histochemical examination confirmed that the tumor was located inside the gallbladder and adjacent liver parenchyma of mice.

Conclusions

Our study showed that a fluorescent IGF-1R-targeted antibody could help detect gallbladder tumors. Tumor-specific imaging technology can be applied to endoscopy, laparoscopy, and robotic surgery for better management of gallbladder cancer.

Combination Treatment of OSI-906 with Aurora B Inhibitor Reduces Cell Viability via Cyclin B1 Degradation-Induced Mitotic Slippage

Insulin-like growth factor 1 receptor (IGF1R), a receptor-type tyrosine kinase, transduces signals related to cell proliferation, survival, and differentiation. We recently reported that OSI-906, an IGF1R inhibitor, in combination with the Aurora B inhibitor ZM447439 suppresses cell proliferation. However, the mechanism underlying this suppressive effect is yet to be elucidated. In this study, we examined the effects of combination treatment with OSI-906 and ZM447439 on cell division, so as to understand how cell proliferation was suppressed. Morphological analysis showed that the combination treatment generated enlarged cells with aberrant nuclei, whereas neither OSI-906 nor ZM447439 treatment alone caused this morphological change. Flow cytometry analysis indicated that over-replicated cells were generated by the combination treatment, but not by the lone treatment with either inhibitors. Time-lapse imaging showed mitotic slippage following a severe delay in chromosome alignment and cytokinesis failure with furrow regression. Furthermore, in S-trityl-l-cysteine–treated cells, cyclin B1 was precociously degraded. These results suggest that the combination treatment caused severe defect in the chromosome alignment and spindle assembly checkpoint, which resulted in the generation of over-replicated cells. The generation of over-replicated cells with massive aneuploidy may be the cause of reduction of cell viability and cell death. This study provides new possibilities of cancer chemotherapy.

Molecular Oncology of Gall Bladder Cancer

Gall bladder carcinoma (GBC) is a worldwide problem, with a higher incidence in areas of the world where cholelithiasis is common. As GBC is usually diagnosed in an advanced stage, the mortality is high. An understanding of the molecular pathways of carcinogenesis and the mutations involved in the development and progression of GBC could be useful in early diagnosis. Understanding molecular markers of prognosis as well as predictors of outcome could also potentially benefit patients undergoing treatment. New therapies targeting major molecular pathways and immunotherapy are exciting novel therapeutic options. This review focuses on the current understanding of the molecular oncology of GBC.

Targeting Insulin-Like Growth Factor 1 Receptor Delays M-Phase Progression and Synergizes with Aurora B Inhibition to Suppress Cell Proliferation

The insulin-like growth factor 1 receptor (IGF1R) is a receptor-type tyrosine kinase that transduces signals related to cell proliferation, differentiation, and survival. IGF1R expression is often misregulated in tumor cells, but the relevance of this for cancer progression remains unclear. Here, we examined the impact of IGF1R inhibition on cell division. We found that siRNA-mediated knockdown of IGF1R from HeLa S3 cells leads to M-phase delays. Although IGF1R depletion causes partial exclusion of FoxM1 from the nucleus, quantitative real-time PCR revealed that the transcription of M-phase regulators is not affected by decreased levels of IGF1R. Moreover, a similar delay in M phase was observed following 2 h of incubation with the IGF1R inhibitors OSI-906 and NVP-ADW742. These results suggest that the M-phase delay observed in IGF1R-compromised cells is not caused by altered expression of mitotic regulators. Live-cell imaging revealed that both prolonged prometaphase and prolonged metaphase underlie the delay and this can be abrogated by the inhibition of Mps1 with AZ3146, suggesting activation of the Spindle Assembly Checkpoint when IGF1R is inhibited. Furthermore, incubation with the Aurora B inhibitor ZM447439 potentiated the IGF1R inhibitor-induced suppression of cell proliferation, opening up new possibilities for more effective cancer chemotherapy.

mTOR Inhibitors in Advanced Biliary Tract Cancers

Patients with advanced biliary tract cancers (BTCs), including cholangiocarcinoma (CCA), have poor prognosis so novel treatment is warranted for advanced BTC. In current review, we discuss the limitations of current treatment in BTC, the importance of mTOR signalling in BTC, and the possible role of mTOR inhibitors as a future treatment in BTC. Chemotherapy with gemcitabine-based chemotherapy is still the standard of care and no targeted therapy has been established in advanced BTC. PI3K/AKT/mTOR signaling pathway linking to several other pathways and networks regulates cancer proliferation and progression. Emerging evidences reveal mTOR activation is associated with tumorigenesis and drug-resistance in BTC. Rapalogs, such as sirolimus and everolimus, partially inhibit mTOR complex 1 (mTORC1) and exhibit anti-cancer activity in vitro and in vivo in BTC. Rapalogs in clinical trials demonstrate some activity in patients with advanced BTC. New-generation mTOR inhibitors against ATP-binding pocket inhibit both TORC1 and TORC2 and demonstrate more potent anti-tumor effects in vitro and in vivo, however, prospective clinical trials are warranted to prove its efficacy in patients with advanced BTC.

Visceral Obesity Is Associated with Gallbladder Polyps

Background/Aims

Gallbladder polyps (GBP) are a common clinical finding and may possess malignant potential. We conducted this study to determine whether visceral obesity is a risk factor for GBP.

Methods

We retrospectively reviewed records of subjects who received both ultrasonography and computed tomography with measurements of the areas of visceral adipose tissue and total adipose tissue (TAT) on the same day as health checkups.

Results

Ninety-three of 1,615 subjects (5.8%) had GBP and were compared with 186 age- and sex-matched controls. VAT (odds ratio [OR], 2.941; 95% confidence interval [CI], 1.325 to 6.529; p=0.008 for the highest quartile vs the lowest quartile) and TAT (OR, 3.568; 95% CI, 1.625 to 7.833; p=0.002 for the highest quartile vs the lowest quartile) were independent risk factors together with hypertension (OR, 2.512; 95% CI, 1.381 to 4.569; p=0.003), diabetes mellitus (OR, 2.942; 95% CI, 1.061 to 8.158; p=0.038), hepatitis B virus positivity (OR, 3.548; 95% CI, 1.295 to 9.716; p=0.014), and a higher level of total cholesterol (OR, 2.232; 95% CI, 1.043 to 4.778; p=0.039 for <200 mg/dL vs ≥240 mg/dL). Body mass index and waist circumference were not meaningful variables.

Conclusions

Visceral obesity measured by VAT and TAT was associated with GBP irrespective of body mass index or waist circumference.

Sweetened Beverage Consumption and Risk of Biliary Tract and Gallbladder Cancer in a Prospective Study

BACKGROUND

Sugar-sweetened beverage consumption raises blood glucose concentration and has been positively associated with weight gain and type 2 diabetes, all of which have been implicated in the development of biliary tract cancer (BTC). This study examined the hypothesis that sweetened beverage consumption is positively associated with risk of BTC in a prospective study.

METHODS

The study population comprised 70 832 Swedish adults (55.9% men, age 45-83 years) from the Swedish Mammography Cohort and Cohort of Swedish Men who were free of cancer and diabetes and completed a food frequency questionnaire at baseline. Incident BTC case patients were ascertained through linkage with the Swedish Cancer Register. Cox proportional hazards regression model was used to analyze the data. All statistical tests were two-sided.

RESULTS

During a mean follow-up of 13.4 years, 127 extrahepatic BTC case patients (including 71 gallbladder cancers) and 21 intrahepatic BTC case patients were ascertained. After adjustment for other risk factors, women and men in the highest category of combined sugar-sweetened and artificially sweetened beverage consumption had a statistically significantly increased risk of extrahepatic BTC and gallbladder cancer. The multivariable hazard ratios for two or more servings per day (200 mL/serving) of sweetened beverages compared with no consumption were 1.79 (95% confidence interval [CI] = 1.02 to 3.13) for extrahepatic BTC and 2.24 (95% CI = 1.02 to 4.89) for gallbladder cancer. The corresponding hazard ratio for intrahepatic BTC was 1.69 (95% CI = 0.41 to 7.03).

CONCLUSIONS

These findings support the hypothesis that high consumption of sweetened beverages may increase the risk of BTC, particularly gallbladder cancer.

Prospective Study of Glycemic Load, Glycemic Index, and Carbohydrate Intake in Relation to Risk of Biliary Tract Cancer

OBJECTIVES

Diets that induce a high glycemic response might increase the risk of biliary tract cancer (BTC). We evaluated the hypothesis that diets with high glycemic load (GL) and high glycemic index (GI), which are measures of the glycemic effect of foods, are associated with an increased incidence of BTC.

METHODS

We used data from a population-based prospective study of 76,014 Swedish adults (age 45-83 years; 57% men) who were free of cancer and had completed a food-frequency questionnaire in the autumn of 1997. Incident cancer cases were ascertained by linkage with the Swedish Cancer Registry. Data were analyzed using Cox proportional hazards regression models.

RESULTS

During a mean follow-up of 13.3 years (1,010,777 person-years), we identified 140 extrahepatic BTC cases (including 77 gallbladder cancers) and 23 intrahepatic BTC cases. A high dietary GL was associated with an increased risk of BTC. The multivariable relative risks for the highest versus lowest quartile of dietary GL were 1.63 (95% confidence interval (95% CI), 1.01-2.63) for extrahepatic BTC, 2.14 (95% CI, 1.06-4.33) for gallbladder cancer, and 3.46 (95% CI, 1.22-9.84) for intrahepatic BTC. Dietary GI was statistically significantly positively associated with risk of extrahepatic BTC and gallbladder cancer. We observed no statistically significant association between carbohydrate intake and BTC risk, although all associations were positive.

CONCLUSION

Although these data do not prove a causal relationship, they are consistent with the hypothesis that high-GL and high-GI diets are associated with an increased risk of BTC.

Expert consensus document: Cholangiocarcinoma: current knowledge and future perspectives consensus statement from the European Network for the Study of Cholangiocarcinoma (ENS-CCA)

Cholangiocarcinoma (CCA) is a heterogeneous group of malignancies with features of biliary tract differentiation. CCA is the second most common primary liver tumour and the incidence is increasing worldwide. CCA has high mortality owing to its aggressiveness, late diagnosis and refractory nature. In May 2015, the "European Network for the Study of Cholangiocarcinoma" (ENS-CCA: www.enscca.org or www.cholangiocarcinoma.eu) was created to promote and boost international research collaboration on the study of CCA at basic, translational and clinical level. In this Consensus Statement, we aim to provide valuable information on classifications, pathological features, risk factors, cells of origin, genetic and epigenetic modifications and current therapies available for this cancer. Moreover, future directions on basic and clinical investigations and plans for the ENS-CCA are highlighted.

MicroRNA-497 regulates cell proliferation in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary cancer of the liver. MicroRNA-497 (miR-497) is known to be downregulated in several types of human cancer; however, the expression, function and underlying mechanisms of miR-497 in HCC remain unclear. Therefore, the present study investigated miR-497 expression in HCC samples and HCC-derived cell lines using reverse transcription-quantitative polymerase chain reaction. The protein expression of one of the predicted common targets of miR-497, insulin-like growth factor-1 receptor (IGF-1R), was assessed using western blot analyses and immunohistochemistry. The role of miR-497 in regulating the proliferation of HCC-derived cells was also investigated in vitro and in vivo. Of 60 paired specimens from HCC patients, miR-497 was downregulated in 42 cancer specimens compared with adjacent non-cancer tissues. Western blotting and immunohistochemical analyses revealed that IGF-1R expression was significantly increased in HCC compared to control tissues. In addition, overexpression of miR-497 was observed to inhibit colony formation and tumor growth in MHCC-97H human HCC cells. Conversely, SMMC-7721 human HCC cells transfected with a miR-497 inhibitor exhibited enhanced colony formation and tumor growth. Finally, IGF-1R protein, phosphoinositide 3-kinase/Akt signaling pathway-associated proteins and cyclin pathway-associated proteins were differentially expressed between miR-497-overexpressing cells and miR-497-silenced cells. These results indicate that miR-497 may be a potentially effective gene therapy target.

Evaluation of miR-29c inhibits endotheliocyte migration and angiogenesis of human endothelial cells by suppressing the insulin like growth factor 1

MicroRNAs, a class of 22-nucleotide non-coding RNAs, modulate gene expression by associating with the 3'-untranslated regions (3'- UTRs) of messenger RNAs (mRNAs). Although multiple miRNAs are known to be regulated during angiogenesis, their individual roles in blood vessel development are still not fully understood. Herein, we investigate the role of miR-29c in regulating cell cycle and angiogenic phenotype of endothelial cells. The results showed that IGF-1 is highly expressed and down-regulated by miR-29c in human umbilical vein endothelial cells (HUVEC). Consistent with this preliminary finding, introduction of exogenous miR-29c or miR-29c inhibitor alters cell cycle progression, proliferation and tube formation of HUVEC, respectively. Furthermore, by using luciferase reporter assay, we find that the expression of IGF-1, a suppressor transcription factor, is directly regulated by miR-29c through 3'-UTR. In addition, we show that the selective inhibition of PI3K/AKT pathway prior to miR-29c stimulation prevents the expression of angiogenesis suppressor miRNAs that are family and cluster specific. As a conclusion, we find that miR-29c plays a significant role in regulating cell cycle, proliferation and angiogenic properties of HUVECs. This function is likely mediated through IGF-1 proteins at the post-transcriptional level. As a novel molecular target, miR-29c may have a potential value in the treatment of angiogenesis-associated diseases, such as cardiovascular diseases and cancers.

Insulin-like growth factor-1 receptor is associated with better prognosis in classical Hodgkin's lymphoma: Correlation with MET expression

The purpose of this study was to examine the prognostic significance of insulin-like growth factor-1 receptor (IGF-1R) expression alone and in relation to the expression of the MET- receptor and the MET-homologous receptor RON, in classical Hodgkin's lymphoma (cHL). Tumour samples from patients with cHL (n = 202; median age 37.5 years) were analysed retrospectively for IGF-R1, MET or RON expression by immunohistochemistry using tissue microarrays. The median follow-up time was 3.7 years (range, 0.1-20 years). Twenty-nine patients (14.3%) expressed IGF-1R protein in Hodgkin/Reed-Sternberg (HRS) cells, which was associated with a better overall survival (OS) (P = 0.036). IGF-1R expression was closely associated with MET receptor expression and low level of lactate dehydrogenase. In patients with cHL receiving doxorubicin, bleomycin, vinblastine and dacarbazine, those expressing IGF-1R showed a trend towards better OS and event-free survival than IGF-1R-negative patients (P = 0.129 and P = 0.115 respectively), but statistical significance was not reached. This study suggests that IGF-1R expression could be associated with better clinical outcome in cHL but is significantly associated with the expression of MET receptor.

Evaluation of miR-29c inhibits endotheliocyte migration and angiogenesis of human endothelial cells by suppressing the insulin like growth factor 1

MicroRNAs, a class of 22-nucleotide non-coding RNAs, modulate gene expression by associating with the 3'-untranslated regions (3'-UTRs) of messenger RNAs (mRNAs). Although multiple miRNAs are known to be regulated during angiogenesis, their individual roles in blood vessel development are still not fully understood. Herein, we investigate the role of miR-29c in regulating cell cycle and angiogenic phenotype of endothelial cells. The results showed that IGF-1 is highly expressed and down-regulated by miR-29c in human umbilical vein endothelial cells (HUVEC). Consistent with this preliminary finding, introduction of exogenous miR-29c or miR-29c inhibitor alters cell cycle progression, proliferation and tube formation of HUVEC, respectively. Furthermore, by using luciferase reporter assay, we find that the expression of IGF-1, a suppressor transcription factor, is directly regulated by miR-29c through 3'-UTR. In addition, we show that the selective inhibition of PI3K/AKT pathway prior to miR-29c stimulation prevents the expression of angiogenesis suppressor miRNAs that are family and cluster specific. As a conclusion, we find that miR-29c plays a significant role in regulating cell cycle, proliferation and angiogenic properties of HUVECs. This function is likely mediated through IGF-1 proteins at the post-transcriptional level. As a novel molecular target, miR-29c may have a potential value in the treatment of angiogenesis-associated diseases, such as cardiovascular diseases and cancers.

Expression of insulin-like growth factor I receptor as a biomarker for predicting prognosis in biliary tract cancer patients

Carcinomas of the gallbladder (GBCa) and bile ducts are aggressive tumors with poor survival and it is, therefore, essential to elucidate the molecular mechanisms of the various signaling pathways in order to develop effective therapies. In this study, tumor specimens from 40 GBCa patients, 12 extrahepatic bile duct carcinoma patients and 26 intrahepatic bile duct carcinoma patients from the USA and Japan were investigated for insulin-like growth factor I receptor (IGF-IR), mammalian target of rapamycin (mTOR) and rapidly accelerated fibrosarcoma-1 (Raf-1) expression by immunohistochemistry; in addition, the correlations with histological type, pathological stage and patient outcome were analyzed. Positive expression of IGF-IR, mTOR and Raf-1 were identified in 68, 73 and 85% of the specimens, respectively. There was no association with histological type and pathological stage, although the positive expression rate of Raf-1 was higher in advanced-stage GBCa. Moreover, patients with positive expression of IGF-IR exhibited significantly reduced survival compared to those with negative IGF-IR expression. In conclusion, IGF-IR, mTOR and Raf-1 were highly expressed in biliary tract cancer and targeted therapy against IGF-IR may be an effective strategy. Among these molecules, IGF-IR expression was found to be a useful biomarker for identifying patients who may benefit from additional treatment.

Phosphorylated insulin-like growth factor-1 receptor expression predicts poor prognosis of Chinese patients with gastric cancer

Previous studies have established the role of phosphorylated form of insulin-like growth factor type 1 receptor (p-IGF1R) as a good candidate for tumor biomarker. The aims of this study were to investigate p-IGF1R expression status in gastric cancer (GC) specimens and to clarify its clinical significance. A total of 78 GC patients treated with radical resection were enrolled in this study. Immunohistochemistry was used to detect p-IGF1R and phosphatase and tensin homolog deleted on chromosome ten (PTEN) protein expression in paired tumor and adjacent normal tissues. Results showed a higher level of p-IGF1R protein expression in tumor tissues than that in normal tissues, and the rate of p-IGF1R protein high/moderate expression in GC and normal tissues was 52.6% (41/78) and 6.4% (5/78), respectively (p < 0.001). In contrast, PTEN protein expression was downregulated in GC, as compared with normal tissues (negative/low expression 49/78 vs. 8/78, p < 0.001). Moreover, PTEN protein downregulation was consistent with p-IGF1R upregulation. Overexpression of p-IGF1R protein was associated with lymph metastasis, clinical stage, and adverse 3-year progression-free survival (PFS). Survival analysis and Cox proportional hazards model revealed that p-IGF1R overexpression was an independent factor in predicting PFS for GC patients, apart from lymph metastasis. In conclusion, p-IGF1R is highly expressed in GC, which may be a novel biomarker to predict the clinical outcome of GC patients.

Insulin-like growth factor 1 receptor is a prognostic factor in classical Hodgkin lymphoma

The interaction between the tumor cells in classical Hodgkin lymphoma (cHL) and the microenvironment includes aberrant activity of receptor tyrosine kinases. In this study we evaluated the expression, functionality and prognostic significance of Insulin-like growth factor-1 receptor (IGF-1R) in cHL. IGF-1R was overexpressed in 55% (44/80) of cHL patients. Phosphorylated IGF-1R was detectable in a minority of the IGF-1R positive tumor cells. The overall survival (OS, 98%) and 5-year progression-free survival (PFS, 93%) was significantly higher in IGF-1R positive cHL patients compared to IGF-1R negative patients (OS 83%, p = .029 and PFS 77%, p = .047, respectively). Three cHL cell lines showed expression of IGF-1R, with strong staining especially in the mitotic cells and expression of IGF-1. IGF-1 treatment had a prominent effect on the cell growth of L428 and L1236 cells and resulted in an increased phosphorylation of IGF1R, Akt and ERK. Inhibition of IGF-1R with cyclolignan picropodophyllin (PPP) decreased cell growth and induced a G2/M cell cycle arrest in all three cell lines. Moreover, a decrease in pCcd2 and an increase in CyclinB1 levels were observed which is consistent with the G2/M cell cycle arrest. In conclusion, IGF-1R expression in HRS cells predicts a favorable outcome, despite the oncogenic effect of IGF-1R in cHL cell lines.

Targeting non-small cell lung cancer cells by dual inhibition of the insulin receptor and the insulin-like growth factor-1 receptor

Phase III trials of the anti-insulin-like growth factor-1 receptor (IGF1R) antibody figitumumab in non-small cell lung cancer (NSCLC) patients have been discontinued owing to lack of survival benefit. We investigated whether inhibition of the highly homologous insulin receptor (IR) in addition to the IGF1R would be more effective than inhibition of the IGF1R alone at preventing the proliferation of NSCLC cells. Signalling through IGF1R and IR in the NSCLC cell lines A549 and Hcc193 was stimulated by a combination of IGF1, IGF2 and insulin. It was inhibited by antibodies that block ligand binding, αIR3 (IGF1R) and IR47-9 (IR), and by the ATP-competitive small molecule tyrosine kinase inhibitors AZ12253801 and NVPAWD742 which inhibit both IGF1R and IR tyrosine kinases. The effect of inhibitors was determined by an anchorage-independent proliferation assay and by analysis of Akt phosphorylation. In Hcc193 cells the reduction in cell proliferation and Akt phosphorylation due to anti-IGF1R antibody was enhanced by antibody-mediated inhibition of the IR whereas in A549 cells, with a relatively low IR:IGF1R expression ratio, it was not. In each cell line proliferation and Akt phosphorylation were more effectively inhibited by AZ12253801 and NVPAWD742 than by combined αIR3 and IR47-9. When the IGF1R alone is inhibited, unencumbered signalling through the IR can contribute to continued NSCLC cell proliferation. We conclude that small molecule inhibitors targeting both the IR and IGF1R more effectively reduce NSCLC cell proliferation in a manner independent of the IR:IGF1R expression ratio, providing a therapeutic rationale for the treatment of this disease.

Expression of insulin-like growth factor 1 and insulin-like growth factor 1 receptor is associated with the favorable clinicopathologic parameters in small intestinal carcinomas

OBJECTIVE

The insulin-like growth factor (IGF) system has been known to play a critical role in tumor development and progression in many human cancers. However, the role of the IGF system in small intestinal carcinoma (SIC) has not been studied yet.

METHODS

We evaluated the expression of IGF1 and IGF1 receptor (IFG1R) in a total of 194 cases of SIC.

RESULTS

IGF1 expression was associated with well/moderate differentiation, better survival, lower pT, lower stage and no lymph node metastasis. IGF1R was more diffusely and strongly expressed in tumors with lower pT and lower stage.

CONCLUSIONS

IGF1 and IGF1R expression is associated with favorable clinicopathologic parameters and may involve early carcinogenesis of SICs. Target therapy for the IGF1R signaling pathway may not have a major therapeutic role in treating SIC.

Molecularly targeted therapy of gallbladder carcinoma

Gallbladder cancer (GBC) represents the most common and aggressive type of biliary tree cancers (BTCs). Complete surgical resection offers the only chance for cure; however, only 10% of patients with GBC present with early-stage disease and are considered surgical candidates. Among those patients who do undergo "curative" resection, recurrence rates are high. There are no established adjuvant treatments in this setting. Patients with unresectable or metastatic GBC have a poor prognosis. Molecularly targeted therapy offers a promising approach for the treatment of unresectable or metastatic GBC. Molecules involved in carcinogenesis or pathogenesis of GBC are target candidates. Molecularly targeted agents that inhibit angiogenesis and epidermal growth factor receptor (EGFR) pathways are entering clinical trials. Further understanding of the molecular mechanism of carcinogenesis coupled with more extensive genetic profiling of GBC patients will help assess the therapeutic relevance of targeting a specific pathway.

Insulin-like growth factor receptor expression is associated with aggressive phenotypes and has therapeutic activity in biliary tract cancers

Insulin-like growth factor (IGF)-I receptor (IGF-IR) signaling is required for carcinogenicity and progression of several cancers but the function of this pathway and its utility as a therapeutic target have not been studied comprehensively in biliary tract carcinomas (BTC). We investigated the immunohistochemical expression of elements of the IGF axis, matrilysin, overexpression of p53 and the methylation status of the IGFBP-3 promoter in 80 surgically resected BTC. We also assessed the effect of IGF-IR blockade on signal transduction, proliferation and survival in three BTC cell lines using a new tyrosine kinase inhibitor, BMS-536924, and dominant negative IGF-IR (IGF-IR/dn). The effects of IGF-IR blockade was also studied in nude mouse xenograft models. IGF-I was expressed in 60% and IGF-II in 50% of tumors. High expression was associated with tumor size. IGF-IR was expressed in 69% of the cases and was associated with advanced stage and matrilysin expression. Hypermethylation of the IGFBP-3 promoter was detected in 41% of BTC and was inversely correlated with p53 expression. BMS-536924 blocked autophosphorylation of IGF-IR and both Akt and ERK activation by both IGF-I and insulin. BMS-536924 suppressed proliferation and tumorigenicity in vitro in a dose-dependent fashion. This inhibitor upregulated chemotherapy-induced apoptosis in a dose-dependent fashion. Moreover, IGF-IR blockade was effective against tumors in mice. IGF-IR might identify a subset of BTC with a particularly aggressive phenotype and is a candidate therapeutic target in this disease. BMS-536924 might have significant therapeutic utility.

Development of molecularly targeted therapies in biliary tract cancers: reassessing the challenges and opportunities

Biliary tract cancers (BTCs), which encompass intra- and extrahepatic cholangiocarcinomas as well as gallbladder carcinomas, are a genetically diverse collection of cancers. Most patients with BTC will present with unresectable or metastatic disease. Although the standard systemic chemotherapy approaches are emerging, the prognosis remains poor. Development of molecularly targeted therapies in advanced BTC remains challenging. Recent early-stage clinical trials with targeted therapies appear promising, although the relationships between subsets of patients with positive responses to therapy and tumor genetics remain unexplored. Here we summarize the relevant molecular pathogenesis, recent and ongoing clinical trials with targeted agents, and the key issues in clinical trial design in BTC.

Gender-Specific Prognostic Markers of Patients with Gallbladder Cancer after Surgical Resection

The aim of this study was to elucidate gender-specific markers for postresectional long-term survival of gallbladder cancer (GBC) based on a cohort of Chinese patients. Clinicopathological records of 81 patients (27 males and 54 females) after surgical resection for GBC were reviewed retrospectively. The influence of each variable on survival was determined using the Kaplan-Meier method and log-rank test. For females, Cox regression analysis was also adopted. Univariate analysis showed that the absence of lymph node and distant metastases, differentiation grade, and curative resection were associated with prolonged survival for all males, whereas tumor size, differentiation grade, and the presence of lymph node metastases influenced the overall or disease-free survival of patients after curative resection (all P < 0.05). On the other hand, Nevin stage was an independent marker for both overall survival for all females and overall and disease-free survival for female patients who underwent curative resection. Additionally, resection type and differentiation grade were of independent prognostic significance for different subgroups of females (all P < 0.05). Our data suggested that tumor-related factors affect prognosis of both male and female patients with GBC after resection. Of these factors, tumor differentiation status might be more significant for males, but Nevin stage had a stronger predictive potential for females.

Genetics of biliary tract cancers and emerging targeted therapies

Biliary tract cancers (BTC), which encompass intra- and extrahepatic cholangiocarcinomas and gallbladder carcinomas, are a genetically diverse collection of cancers. Evidence suggests distinct models of molecular and pathologic progression, and a growing body of genetics data points to a heterogeneous collection of underlying mutations in key oncogenes and tumor suppressor genes. Although tumor genetics have been used to tailor individual treatment regimens and guide clinical decision making in other cancers, these principles have not been applied in BTC. Recent clinical trials with targeted therapies seem promising, although the relationships between subsets of patients with positive responses to therapy and tumor genetics remain unexplored. Here, we summarize the molecular pathogenesis and genetics of BTCs and animal modeling and relate these to recent and ongoing clinical trials with targeted agents.

Mutational and immunohistochemical study of the PI3K/Akt pathway in papillary thyroid carcinoma in Greece

PI3K/Akt signaling pathway plays critical role in many cell processes. There is indication that enhanced activation of PI3K/Akt cascade is implicated in thyroid tumors. Aim of this study was to evaluate the mutational status and expression of PI3K/Akt pathway mediators in papillary thyroid carcinoma in Greece. We evaluated the presence of mutations in PIK3CA (exons 9 and 20), AKT1 (exons 6-11), AKT2 (exons 6-11), AKT3 (exons 5-10), PTEN (exons 3-8), and PDPK1 (exons 4-10) genes in 83 papillary thyroid carcinomas by DNA sequencing. The expression levels of phospho-Akt and insulin-like growth factor I receptor (IGF-IR) were evaluated by immunohistochemistry. PIK3CA mutations were found in three samples. The analysis of AKT1 revealed one silent mutation in exon 9 (G726A) in 16 samples. One specimen carried an AKT3 mutation. One missense mutation was found in one sample in PTEN. No mutations were found in AKT2 and PDPK1. Increased levels of phosphorylated total Akt and IGF-IR were identified in some papillary cancers. Our findings indicate that PI3K/Akt signaling pathway is activated in some papillary tumors. However, mutations in genes coding most mediators of the pathway have not been proven to be the major modus of enhanced activation. These data suggest a potential role for PI3K/Akt-mediated signaling in papillary thyroid tumors.

Treatment of biliary tract cancer with NVP-AEW541: Mechanisms of action and resistance

AIM: To investigate in vitro treatment with NVP-AEW541, a small molecule inhibitor of insulin-like growth factor-1 receptor (IGF-1R), in biliary tract cancer (BTC), since this disease is associated with a poor prognosis due to wide resistance to chemotherapeutic agents and radiotherapy.

METHODS: Cell growth inhibition by NVP-AEW541 was studied in vitro in 7 human BTC cell lines by automated cell counting. In addition, the anti-tumoral mechanism of NVP-AEW541 was studied by Western blotting, cell cycle analysis and reverse transcription-polymerase chain reaction (RT-PCR). Anti-tumoral drug effect in combination with gemcitabine, 5-fluorouracil (5-FU) and Polo-like kinase 1 inhibitor BI2536 was also studied.

RESULTS: In vitro treatment with NVP-AEW541 suppressed growth in all human BTC cell lines, however response was lower in gallbladder cancer. Treatment with NVP-AEW541 was associated with dephosphorylation of IGF-1R and AKT. In contrast, phosphorylation of p42/p44 and Stat3 and expression of Bcl-xL were inconsistently downregulated. In addition, treated cells showed cell cycle arrest at the G1/S-checkpoint and an increase in sub-G1 peak. Moreover, IGF-1R and its ligands IGF-1 and IGF-2 were co-expressed in RT-PCR, suggesting an autocrine loop of tumor cell activation. Combined with gemcitabine, NVP-AEW541 exerted synergistic effects, particularly at low concentrations, while effects of combination with 5-FU or BI 2536 were only additive.

CONCLUSION: Our findings suggest that NVP-AEW541 is active against BTC in vitro and potentiates the efficacy of gemcitabine.

Head and neck squamous cancer stromal fibroblasts produce growth factors influencing phenotype of normal human keratinocytes

Epithelial-mesenchymal interaction between stromal fibroblasts and cancer cells influences the functional properties of tumor epithelium, including the tumor progression and spread. We compared fibroblasts prepared from stroma of squamous cell carcinoma and normal dermal fibroblasts concerning their biological activity toward normal keratinocytes assessed by immunocytochemistry and profiling of gene activation for growth factors/cytokines by microarray chip technology. IGF-2 and BMP-4 were determined as candidate factors responsible for tumor-associated fibroblast activity that influences normal epithelia. This effect was confirmed by addition of recombinant IGF-2 and BMP4, respectively, to the culture medium. This hypothesis was also verified by inhibition experiments where blocking antibodies were employed in the medium conditioned by cancer-associated fibroblast. Presence of these growth factors was also detected in tumor samples.

The insulin-like growth factor-I receptor as an oncogene

The insulin-like growth factor-I receptor (IGF-IR) mediates the biological actions of both IGF-I and IGF-II. The IGF-IR is expressed in most transformed cells, where it displays potent antiapoptotic, cell-survival, and transforming activities. IGF-IR expression is a fundamental prerequisite for the acquisition of a malignant phenotype, as suggested by the finding that IGF-IR-null cells (derived from IGF-IR knock-out embryos) are unable to undergo transformation when exposed to cellular or viral oncogenes. This review article will focus on the underlying molecular mechanisms that are responsible for the normal, physiological control of IGF-IR gene expression, as well as the cellular pathways that underlie its aberrant expression in cancer. Examples from the clinics will be presented, including a description of how the IGF system is involved in breast, prostate, pediatric, and gynecological cancers. Finally, current attempts to target the IGF-IR as a therapeutic approach will be described.

Phosphorylated Insulin Like Growth Factor-I Receptor Expression and Its Clinico-Pathological Significance in Histologic Subtypes of Human Thyroid Cancer

Overexpression of insulin-like growth factor-I receptor (IGF-IR) is seen in a multitude of human thyroid cancers and correlates with poor prognosis. However, recent studies suggest that low phospho-IGF-IR (pIGF-IR) expression rather than its overexpression may be an indicator of poorly differentiated disease. No previous study has evaluated the expression of pIGF-IR to determine if activation or loss of expression of this receptor is associated with thyroid tumor progression. Accordingly, a quantitative immunohistochemical (IHC) method was used to evaluate the clinico-pathological significance of pIGF-IR expression in archival samples of human thyroid carcinomas. Quantitative analysis of pIGF-IR levels revealed a significant difference in the median index of pIGF-IR between different histological subtypes of thyroid cancer ( P < 0.001). Specifically, the median pIGF-IR index of differentiated thyroid cancers was significantly higher than the median index of other poorly differentiated thyroid cancer ( P < 0.001). This was further confirmed in individual tumor sections of thyroid carcinoma where anaplastic and differentiated components co-existed. No significant difference was noted in the pIGF-IR index of tumors grouped by size or stage but a trend towards lower mean pIGF-IR index was noted in older patients. Our data indicates that pIGF-IR is upregulated in a majority of follicular thyroid carcinomas, suggesting it may be a potential target for therapy for patients with this disease. In addition, since low pIGF-IR expression was found to correlate with aggressive human thyroid carcinoma, it also suggests that IGF-IR may not be needed for progression of anaplastic thyroid carcinoma possibly because other cell signaling pathways are activated, obviating the need for IGF-IR signaling. However, more mechanistic studies would be necessary to substantiate the possibility that pIGF-IR may be important for differentiation of thyroid tissues and is lost with disease progression.

The role of the IGF system in cancer growth and metastasis: overview and recent insights

IGF-I receptor (IGF-IR) signaling and functions are mediated through the activities of a complex molecular network of positive (e.g., type I IGF) and negative (e.g., the type II IGF receptor, IGF-IIR) effectors. Under normal physiological conditions, the balance between the expression and activities of these molecules is tightly controlled. Changes in this delicate balance (e.g., overexpression of one effector) may trigger a cascade of molecular events that can ultimately lead to malignancy. In recent years, evidence has been mounting that the IGF axis may be involved in human cancer progression and can be targeted for therapeutic intervention. Here we review old and more recent evidence on the role the IGF system in malignancy and highlight experimental and clinical studies that provide novel insights into the complex mechanisms that contribute to its oncogenic potential. Controversies arising from conflicting evidence on the relevance of IGF-IR and its ligands to human cancer are discussed. Our review highlights the importance of viewing the IGF axis as a complex multifactorial system and shows that changes in the expression levels of any one component of the axis, in a given malignancy, should be interpreted with caution and viewed in a wider context that takes into account the expression levels, state of activation, accessibility, and functionality of other interacting components. Because IGF targeting for anticancer therapy is rapidly becoming a clinical reality, an understanding of this complexity is timely because it is likely to have an impact on the design, mode of action, and clinical outcomes of newly developed drugs.