Concomitant high gene copy number and protein overexpression of IGF1R and EGFR negatively affect disease-free survival of surgically resected non-small-cell-lung cancer patients

Mechanism and recent updates on insulin-related disorders

Insulin, a small protein with 51 amino acids synthesized by pancreatic β-cells, is crucial to sustain glucose homeostasis at biochemical and molecular levels. Numerous metabolic dysfunctions are related to insulin-mediated altered glucose homeostasis. One of the significant pathophysiological conditions linked to the insulin associated disorder is diabetes mellitus (DM) (type 1, type 2, and gestational). Insulin resistance (IR) is one of the major underlying causes of metabolic disorders despite its association with several physiological conditions. Metabolic syndrome (MS) is another pathophysiological condition that is associated with IR, hypertension, and obesity. Further, several other pathophysiological disorders/diseases are associated with the insulin malfunctioning, which include polycystic ovary syndrome, neuronal disorders, and cancer. Insulinomas are an uncommon type of pancreatic β-cell-derived neuroendocrine tumor that makes up 2% of all pancreatic neoplasms. Literature revealed that different biochemical events, molecular signaling pathways, microRNAs, and microbiota act as connecting links between insulin disorder and associated pathophysiology such as DM, insuloma, neurological disorder, MS, and cancer. In this review, we focus on the insulin-related disorders and the underlying mechanisms associated with the pathophysiology.

Measurement of Serum EGFR mRNA Expression is a Reliable Predictor of Treatment Response and Survival Outcomes in Non- Small Cell Lung Cancer

BACKGROUND

EGFR over-expression plays a key role in the development and progression of lung cancer. However, its status as a prognostic biomarker for survival outcomes is unclear.

OBJECTIVES

To evaluate the prognostic utility of serum EGFR mRNA expression in Non-Small cell lung cancer (NSCLC) for treatment response and survival.

METHODS

EGFR mRNA levels were determined in serum using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Based on ROC curve, a cut off value of 16.0-fold increase was selected to categorize patients into low EGFR (≤ 16.0) and high EGFR (> 16.0) groups.

RESULTS

A total of 350 subjects were included (78.3% males), with mean (± SD) age of 57.1 (± 11.2) years, and including 247 (70.6%) adenocarcinoma (ADC). Majority (73.1%) had metastatic (stage IV) disease. Patients had higher pre-treatment serum EGFR mRNA levels than controls [median fold-increase (min, max), 16.2 (1.9, 66.7). Serum EGFR mRNA levels significantly reduced in those who achieved objective response and disease control. Significantly longer OS and PFS was observed in subjects having baseline EGFR mRNA expression ≤ 16.0 fold- increase compared to those with > 16.0 fold- increase [median (95% CI) OS: 25.0 (14.9, NR) versus 7.7 (6.3, 8.9) months; HR (95% CI) 2.9 (2.3, 4.0), p < 0.001; and PFS: 9.9 (7.1, 11.5) versus 6.0 (4.1, 7.5) months; HR (95% CI) 1.8 (1.3, 2.4), p < 0.001].

CONCLUSION

Serum EGFR mRNA expression is a useful parameter for predicting treatment response and survival outcomes in NSCLC.

Insulin Receptor Substrate-1 (IRS-1) and IRS-2 expression levels are associated with prognosis in non-small cell lung cancer (NSCLC)

The insulin-like growth factor-1 (IGF-1) signaling pathway has been implicated in non-small cell lung cancer (NSCLC) outcomes and resistance to targeted therapies. However, little is known regarding the molecular mechanisms by which this pathway contributes to the biology of NSCLC. The insulin receptor substrate (IRS) proteins are cytoplasmic adaptor proteins that signal downstream of the IGF-1R and determine the functional outcomes of this signaling pathway. In this study, we assessed the expression patterns of IRS-1 and IRS-2 in NSCLC to identify associations between IRS-1 and IRS-2 expression levels and survival outcomes in the two major histological subtypes of NSCLC, adenocarcinoma (ADC) and squamous cell carcinoma (SCC). High IRS-2 expression was significantly associated with decreased overall survival in adenocarcinoma (ADC) patients, whereas low IRS-1 cytoplasmic expression showed a trend toward association with decreased overall survival in squamous cell carcinoma (SCC) patients. Tumors with low IRS-1 and high IRS-2 expression were found to be associated with poor outcomes in ADC and SCC, indicating a potential role for IRS-2 in the aggressive behavior of NSCLC. Our results suggest distinct contributions of IRS-1 and IRS-2 to the biology of ADC and SCC that impact disease progression.

Prognostic value of IGF-1R in lung cancer: A PRISMA-compliant meta-analysis

BACKGROUND

Insulin-like growth factor receptor 1 (IGF-1R) is a key player in a wide array of pathological processes, while the prognostic role of IGF-1R in lung cancer remains controversial.

METHODS

We conducted a meta-analysis to evaluate the prognostic value of IGF-1R in lung cancer. We searched for recent studies on the expression of IGF-1R and extracted prognostic lung cancer data from the articles.

RESULTS

Eventually, 22 studies with 3859 patients were analyzed in our meta-analysis. Hazard ratios (HRs) and their 95% confidence intervals (CIs) were used to quantify the ability of IGF-1R to predict survival. The results indicated that IGF-1R positive expression was associated with an unfavorable disease-free survival (DFS) in non-small cell lung cancer (NSCLC) patients on univariate analysis (HR = 1.24, 95% CI: 1.00-1.55, P = .054) and multivariate analysis (HR = 1.49, 95% CI: 1.01-2.21, P = .045), but there was no significant difference in the relationship between IGF-1R positive expression and overall survival (OS) on univariate analysis (HR = 1.04, 95% CI: 0.86-1.25, P = .712) and multivariate analysis (HR = 0.89, 95% CI: 0.57-1.39, P = .602). IGF-1R mRNA expression related to OS was obtained in 2 studies, with the pooled HR being 1.663 (95% CI: 1.071-2.583, P = .024). For IGF-1R expression and small cell lung cancer (SCLC), the conclusion was not statistically significant, with the pooled HR being 1.22 (95% CI: 0.66-2.27, P = .524).

CONCLUSIONS

Our results indicate that high expression of IGF-1R predicts poor DFS in NSCLC, yet it does not predict poor OS in NSCLC and SCLC. IGF-1R may be a useful predictor of outcomes in patients with NSCLC.

Identification of key genes and associated pathways in KIT/PDGFRA wild‑type gastrointestinal stromal tumors through bioinformatics analysis

Gastrointestinal stromal tumors (GISTs) are the most common type of mesenchymal tumor in the gastrointestinal tract. The present study aimed to identify the potential candidate biomarkers that may be involved in the pathogenesis and progression of v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog (KIT)/platelet-derived growth factor receptor α (PDGFRA) wild-type GISTs. A joint bioinformatics analysis was performed to identify the differentially expressed genes (DEGs) in wild-type GIST samples compared with KIT/PDGFRA mutant GIST samples. Gene Ontology function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of DEGs was conducted using Database for Annotation, Visualization and Integrated Discovery and KEGG Orthology-Based Annotation System (KOBAS) online tools, respectively. Protein-protein interaction (PPI) networks of the DEGs were constructed using Search Tool for the Retrieval of Interacting Genes online tool and Cytoscape, and divided into sub-networks using the Molecular Complex Detection (MCODE) plug-in. Furthermore, enrichment analysis of DEGs in the modules was analyzed with KOBAS. In total, 546 DEGs were identified, including 238 upregulated genes primarily enriched in ‘cell adhesion’, ‘biological adhesion’, ‘cell-cell signaling’, ‘PI3K-Akt signaling pathway’ and ‘ECM-receptor interaction’, while the 308 downregulated genes were predominantly involved in ‘inflammatory response’, ‘sterol metabolic process’ and ‘fatty acid metabolic process’, ‘small GTPase mediated signal transduction’, ‘cAMP signaling pathway’ and ‘proteoglycans in cancer’. A total of 25 hub genes were obtained and four modules were mined from the PPI network, and sub-networks also revealed these genes were primarily involved in significant pathways, including ‘PI3K-Akt signaling pathway’, ‘proteoglycans in cancer’, ‘pathways in cancer’, ‘Rap1 signaling pathway’, ‘ECM-receptor interaction’, ‘phospholipase D signaling pathway’, ‘ras signaling pathway’ and ‘cGMP-PKG signaling pathway’. These results suggested that several key hub DEGs may serve as potential candidate biomarkers for wild-type GISTs, including phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit γ, insulin like growth factor 1 receptor, hepatocyte growth factor, thrombospondin 1, Erb-B2 receptor tyrosine kinase 2 and matrix metallopeptidase 2. However, further experiments are required to confirm these results.

HSP90: A Novel Target Gene of miRNA-628-3p in A549 Cells

Lung cancer is one of the leading causes of cancer-related death in the world. MicroRNA- (miR-) 628-3p plays critical roles in many cancers, including lung cancer. We investigated how miR-628-3p affected migration and apoptosis in A549 cells. We used bioinformatics algorithms to predict the miR-628-3p target gene to study the molecular mechanism by which miR-628-3p contributes to lung cancer. Then, we used the luciferase reporter assay to identify whether heat shock protein 90a (HSP90) is a direct target of miR-628-3p. Western blotting and quantitative real-time PCR showed that miR-628-3p downregulated HSP90a protein expression via a posttranscriptional mechanism. We confirm that miR-628-3p promotes apoptosis and inhibits migration in A549 cells by negatively regulating HSP90. Our results may reveal a novel strategy for lung cancer treatment.

Personalized Radiation Oncology: Epidermal Growth Factor Receptor and Other Receptor Tyrosine Kinase Inhibitors

Molecular biomarkers are currently evaluated in preclinical and clinical studies in order to establish predictors for treatment decisions in radiation oncology. The receptor tyrosine kinases (RTK) are described in the following text. Among them, the most data are available for the epidermal growth factor receptor (EGFR) that plays a major role for prognosis of patients after radiotherapy, but seems also to be involved in mechanisms of radioresistance, specifically in repopulation of tumour cells between radiotherapy fractions. Monoclonal antibodies against the EGFR improve locoregional tumour control and survival when applied during radiotherapy, however, the effects are heterogeneous and biomarkers for patient selection are warranted. Also other RTK´s such as c-Met and IGF-1R seem to play important roles in tumour radioresistance. Beside the potential to select patients for molecular targeting approaches combined with radiotherapy, studies are also needed to evluate radiotherapy adaptation approaches for selected patients, i.e. adaptation of radiation dose, or, more sophisticated, of target volumes.

Insulin-like Growth Factor 1 Receptor Expression in Advanced Non-small-cell Lung Cancer and its Impact on Overall Survival

BACKGROUND

The insulin-like growth factor 1 receptor (IGF1R) expression has been addressed as a potential prognostic marker in non-small-cell lung cancer (NSCLC) in various studies; however, the associations between IGF1R expression and prognosis of advanced NSCLC patients is still controversial. The aim of our observational, cohort study was to evaluate the expression of IGF1R in advanced NSCLC and its prognostic role. A subgroup analysis was performed to address the influence of pre-existing type 2 diabetes mellitus (T2DM) status on IGF1R expression and overall survival (OS).

PATIENTS AND METHODS

IGF1R expression was evaluated in 167 consecutive advanced NSCLC patients (stage IIIB and IV), diagnosed and treated at one university institution, between 2005 and 2010. All patients received at least one line of standard cytotoxic therapy and 18 of them had pre-existing T2DM. IGF1R expression was determined by immunohistochemical (IHC) staining, with score ≥ 1+ considered as positive. Information on baseline characteristics, as well as patients' follow-up data, were obtained from the hospital registry. Associations of IGF1R expression with clinical characteristics and overall survival were compared.

RESULTS

IGF1R expression was positive in 79.6% of patients, significantly more often in squamous-cell carcinoma (SCC) compared to non-squamous-cell (NSCC) histology (88.7% vs. 74.3%; P = 0.03). IGF1R positivity did not correlate with T2DM status or with other clinical features (sex, smoking status, performance status). Median OS was similar between IGF1R positive and IGF1R negative group (10.2 vs. 8.5 months, P = 0.168) and between patients with or without T2DM (8.7 vs. 9.8 months, P = 0.575). Neither IGF1R expression nor T2DM were significant predictors of OS.

CONCLUSIONS

IGF1R or T2DM status were not significantly prognostic in described above collective of advanced NSCLC treated with at least one line of chemotherapy. In addition, no association between T2DM status and IGF1R expression was found. Further studies on IGF1R expression and its prognostic as well as therapeutic consequences in a larger collective of advanced NSCLC patients, with or without T2DM, are needed.

Pharmacogenomics of EGFR-targeted therapies in non-small cell lung cancer: EGFR and beyond

Commonly observed aberrations in epidermal growth factor receptor (EGFR) signaling have led to the development of EGFR-targeted therapies for various cancers, including non–small cell lung cancer (NSCLC). EGFR mutations and overexpression have further been shown to modulate sensitivity to these EGFR-targeted therapies in NSCLC and several other types of cancers. However, it is clear that mutations and/or genetic variations in EGFR alone cannot explain all of the variability in the responses of patients with NSCLC to EGFR-targeted therapies. For instance, in addition to EGFR genotype, genetic variations in other members of the signaling pathway downstream of EGFR or variations in parallel receptor tyrosine kinase (RTK) pathways are now recognized to have a significant impact on the efficacy of certain EGFR-targeted therapies. In this review, we highlight the mutations and genetic variations in such genes downstream of EGFR and in parallel RTK pathways. Specifically, the directional effects of these pharmacogenetic factors are discussed with a focus on two commonly prescribed EGFR inhibitors: cetuximab and erlotinib. The results of this comprehensive review can be used to optimize the treatment of NSCLC with EGFR inhibitors. Furthermore, they may provide the rationale for the design of subsequent combination therapies that involve the inhibition of EGFR.

Prognostic and predictive biomarkers in early stage non-small cell lung cancer: tumor based approaches including gene signatures

In early stage non-small cell lung cancer (NSCLC) large randomized trials have demonstrated that in patients with radically resected disease adjuvant chemotherapy improves 5-year survival rates. However, a customization of systemic treatment is needed to avoid treatments in patients cured by surgery alone or to justify the use of adjuvant chemotherapy in high risk patients, including those in stage IA. Recently, the possibility of identifying prognostic and predictive factors related to the genetic signatures of the tumor that could affect adjuvant and neo-adjuvant treatment choices for resectable non-small cell lung cancer (NSCLC) has been of interest. This review summarizes the current status and future opportunities for clinical application of genotyping and genomic tests in early NSCLC.

Insulin-like growth factor receptor 1 (IGF1R) expression and survival in non-small cell lung cancer patients: a meta-analysis

The insulin-like growth factor receptor-1 (IGF1R) plays an important role in cancer progression. Previous studies have been controversial with respect to the associations between IGF1R expression and non small cell lung cancer (NSCLC) prognosis. Thus, we performed a meta-analysis to investigate the prognostic value of IGF1R expression in NSCLC patients and the relationship between the expression of IGF1R and clinical characteristics. Two independent reviewers searched PubMed, Embase, Ovid Medline and CNKI to identify eligible studies. Overall survival (OS), disease free survival (DFS) and clinicopathological characteristics were collected from included studies. Pooled hazard ratios (HRs) or odds ratios (ORs) with 95% confidence interval (95% CI) were calculated to estimate the effect. 17 studies comprising 3,294 patients were included in this meta-analysis. The results showed IGF1R positive expression was associated with an unfavorable DFS in NSCLC patients on univariate analysis (HR = 1.26, 95% CI: 1.09-1.46, P = 0.002) and multivariate analysis (HR = 1.49, 95% CI: 1.01-2.20, p = 0.045), but the relationship between IGF1R expression and OS have no significant difference on univariate analysis (HR = 0.91, 95% CI: 0.82-1.01, P = 0.157) and multivariate analysis (HR = 0.79, 95% CI: 0.45-1.41, P = 0.427). Ever smoking and smaller tumor size (T1 or T2) were associated with IGF1R positive expression: pooled OR 1.45 (1.13-1.85) and pooled OR 0.61 (0.60-0.95). Our results suggested IGF1R positive expression as an unfavorable factor for DFS in NSCLC patients, and IGF1R expression was associated with smoking status and tumor size.

Alterations of insulin-like growth factor-1 receptor gene copy number and protein expression are common in non-small cell lung cancer

Aims

Insulin-like growth factor-1 receptor (IGF1R) is a tyrosine kinase membrane receptor involved in tumourigenesis that may be a potential therapeutic target. We aimed to investigate the incidence and prognostic significance of alterations in IGF1R copy number, and IGF1R protein expression in resected primary non-small cell lung cancer (NSCLC), and lymph node metastases.

Methods

IGF1R gene copy number status was evaluated by chromogenic silver in situ hybridisation and IGF1R protein expression was evaluated by immunohistochemistry in tissue microarray sections from a retrospective cohort of 309 surgically resected NSCLCs and results were compared with clinicopathological features, including EGFR and KRAS mutational status and patient survival.

Results

IGF1R gene copy number status was positive (high polysomy or amplification) in 29.2% of NSCLC, and 12.1% exhibited IGF1R gene amplification. High IGF1R expression was found in 28.3%. There was a modest correlation between IGF1R gene copy number and protein expression (r=0.2, p<0.05). Alterations of IGF1R gene copy number and protein expression in primary tumours were significantly associated with alterations in lymph node metastases (p<0.01). High IGF1R gene copy number and protein expression was significantly higher in squamous cell carcinomas (SCC) compared with other subtypes of NSCLC (p<0.05). There were no other associations between IGF1R status and other clinicopathological features including patient age, gender, smoking status, tumour size, stage, grade, EGFR or KRAS mutational status or overall survival.

Conclusions

High IGF1R gene copy number and protein overexpression are frequent in NSCLC, particularly in SCCs, but they are not prognostically relevant.

Photothermolysis mediated by gold nanorods modified with EGFR monoclonal antibody induces Hep-2 cells apoptosis in vitro and in vivo

Gold nanorods (AuNRs) have been used in plasmonic photothermal therapy (PPTT), which is thought to be more efficient and selective than conventional photothermal therapy. The efficiency and safety of PPTT can be improved by functionally modifying the gold nanorods with proteins or biomolecules. In this study, AuNRs were modified with anti-epidermal growth factor receptor (EGFR) monoclonal antibody (mAb), and the apoptotic potential of EGFRmAb-AuNR was assessed in Hep-2 cells in vitro and in vivo. The EGFRmAb modification had no obvious influence on the original optical property of the AuNRs, but it significantly increased the entry of AuNRs into Hep-2 cells. EGFRmAb-AuNRs, with appropriate laser irradiation, resulted in higher Hep-2 cells apoptosis than AuNRs did alone, in vitro, and was accompanied by alteration of reactive oxygen species (ROS) production, Ca(2+) release, change in mitochondrial membrane potential (ΔΨm), cytochrome c (Cyt-c) release, active caspase-3 expression, and level of B-cell lymphoma 2 (Bcl-2) and B-cell lymphoma 2 protein-associated X protein (Bax). EGFRmAb-AuNR-mediated apoptosis in Hep-2 cells was also observed in vivo and had an inhibitive effect on growth of Hep-2 tumor xenografts. Our data suggest that the EGFRmAb modification improves AuNR-mediated apoptosis and may have the potential to be used clinically.