Immunohistochemical expression of basic fibroblast growth factor and fibroblast growth factor receptors 1 and 2 in the pathogenesis of lung cancer

Sanikovich V, S. Rusanov A, N. Pirogova Y, Boroda A, Rozhkov A, Kemfang Ngowa JD, N. Bagmet L, I. Sekacheva M. Angiogenesis in Lung Cancer: Understanding the Roles of Growth Factors

Research has shown the role of growth factors in lung cancer angiogenesis. Angiogenesis promotes lung cancer progression by stimulating tumor growth, enhancing tumor invasion, contributing to metastasis, and modifying immune system responses within the tumor microenvironment. As a result, new treatment techniques based on the anti-angiogenic characteristics of compounds have been developed. These compounds selectively block the growth factors themselves, their receptors, or the downstream signaling pathways activated by these growth factors. The EGF and VEGF families are the primary targets in this approach, and several studies are being conducted to propose anti-angiogenic drugs that are increasingly suitable for the treatment of lung cancer, either as monotherapy or as combined therapy. The efficacy of the results are encouraging, but caution must be placed on the higher risk of toxicity, outlining the importance of personalized follow-up in the management of these patients.

Role of Basic Fibroblast Growth Factor in Cancer: Biological Activity, Targeted Therapies, and Prognostic Value

Cancer is the leading cause of death worldwide; thus, it is necessary to find successful strategies. Several growth factors, such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF, FGF2), and transforming growth factor beta (TGF-β), are involved in the main processes that fuel tumor growth, i.e., cell proliferation, angiogenesis, and metastasis, by activating important signaling pathways, including PLC-γ/PI3/Ca2+ signaling, leading to PKC activation. Here, we focused on bFGF, which, when secreted by tumor cells, mediates several signal transductions and plays an influential role in tumor cells and in the development of chemoresistance. The biological mechanism of bFGF is shown by its interaction with its four receptor subtypes: fibroblast growth factor receptor (FGFR) 1, FGFR2, FGFR3, and FGFR4. The bFGF–FGFR interaction stimulates tumor cell proliferation and invasion, resulting in an upregulation of pro-inflammatory and anti-apoptotic tumor cell proteins. Considering the involvement of the bFGF/FGFR axis in oncogenesis, preclinical and clinical studies have been conducted to develop new therapeutic strategies, alone and/or in combination, aimed at intervening on the bFGF/FGFR axis. Therefore, this review aimed to comprehensively examine the biological mechanisms underlying bFGF in the tumor microenvironment, the different anticancer therapies currently available that target the FGFRs, and the prognostic value of bFGF.

Inhibition of autophagy potentiates the cytotoxicity of the irreversible FGFR1-4 inhibitor FIIN-2 on lung adenocarcinoma

For patients with platinum-resistant lung adenocarcinoma (LUAD), the exploration of new effective drug candidates is urgently needed. Fibroblast growth factor receptors (FGFRs) have been identified as promising targets for LUAD therapy. The purpose of this study was to determine the exact role of the irreversible FGFR1-4 inhibitor FIIN-2 in LUAD and to clarify its underlying molecular mechanisms. Our results demonstrated that FIIN-2 significantly inhibited the proliferation, colony formation, and migration of A549 and A549/DDP cells but induced the mitochondria-mediated apoptosis of these cells. Meanwhile, FIIN-2 increased the autophagy flux of A549 and A549/DDP cells by inhibiting the mammalian target of rapamycin (mTOR) and further activating the class III PI3K complex pathway. More importantly, in vivo and in vitro experiments showed that autophagy inhibitors could enhance the cytotoxicity of FIIN-2 on A549 and A549/DDP cells, confirming that FIIN-2 induced protective autophagy. These findings indicated that FIIN-2 is a potential drug candidate for LUAD treatment, and its use in combination with autophagy inhibitors might be an efficient treatment strategy, especially for patients with cisplatin resistance.

Intratumoral Cellular Heterogeneity: Implications for Drug Resistance in Patients with Non-Small Cell Lung Cancer

Simple Summary

The number of druggable tumor-specific molecular alterations in the treatment of non-small cell lung cancer (NSCLC) has grown significantly in the past decade. Emerging technologies such as liquid biopsy and single-cell methods allow for studying targetable drivers and develop personalized treatments. However, although new therapies confer prolonged disease control and high tumor response rates, most patients eventually progress on targeted treatments. Intratumoral heterogeneity is a frequent event in NSCLC, driving the tumor cells to develop adaptive or new resistance mechanisms within the drug environment. This review summarizes the current and upcoming research on the biological role of tumor heterogeneity, highlighting the link between early and acquired drug resistance and tumoral heterogeneity in targetable driver mutated NSCLC.

Abstract

Tailored therapies based on the identification of molecular targets currently represent a well-established therapeutic scenario in the treatment of non-small cell lung cancer (NSCLC) patients. However, while aiming to improve patients’ response to therapy, development of resistance is frequently observed in daily clinical practice. Intratumoral heterogeneity is a frequent event in NSCLC, responsible for several critical issues in patients’ diagnosis and treatment. Advances in single-cell sequencing technologies have allowed in-depth profiling of tumors and attributed intratumoral heterogeneity to genetic, epigenetic, and protein modification driven diversities within cancer cell populations. This review highlights current research on the biological role of tumor heterogeneity and its impact on the development of acquired resistance in NSCLC patients.

Uncommon targets in non-small cell lung cancer: Everyone wants a slice of cake

Target therapies completely changed the clinical approach in EGFR mutated and ALK rearranged non-small cell lung cancer, ensuring these patients exceptional outcomes with a better toxicity profile compared to conventional chemotherapy. In recent years, beyond EGFR and ALK alterations, new data are emerging about less common alterations, new drugs have been already approved and others agents have been recently investigated or are currently under investigation. In this review we will discuss some uncommon alterations in non-small cell lung cancer such as ROS1, BRAF, RET, HER2, NTRK, MET and other targets that are in an early evaluation phase. We will summarize the characteristics of patients harboring these alterations, the already approved or under investigation therapies and the related resistance mechanisms.

Fibroblast growth factor receptor 2 expression in apical periodontitis in mice

AIM

To investigate the presence, localization and the possible correlation of the fibroblast growth factor receptor-2 (FGFR2) with inflammatory resorption of cementum, periodontal ligament and alveolar bone during development of apical periodontitis in mice.

METHODOLOGY

Apical periodontitis was experimentally induced in mandibular first molars of mice by pulp exposure to the oral environment. Healthy teeth without pulp exposure were used as controls. At 7, 21 and 42 days following pulp exposure, the animals were euthanized and the jaws were prepared for analysis under conventional and fluorescence microscopy, immunohistochemistry (FGFR2), RT-PCR (RNAm levels of RANK, RANKL, OPG, Runx2 and cathepsin K) and enzyme histochemistry (cementoclasts and osteoclasts). Statistical analysis was performed by Kruskal-Wallis tests and Dunn's post hoc tests for multiple comparisons (α = 0.05) using SAS 9.4 software.

RESULTS

FGFR2-positive cells were not observed in the tissues surrounding healthy teeth but were observed in teeth with periapical lesions from seven days after root canal contamination. At days 21 and 42 after endodontic infection, the increase in periapical lesion size was accompanied by significantly enhanced expression of FGFR2 (P < 0.0001), significantly increased intensity of inflammatory cells, number of osteoclasts (P < 0.0001) and cementoclasts (P < 0.0001), and significantly enhanced RNAm levels of RANK/RANKL/OPG, Runx2 and cathepsin K compared to day 0 (P < 0.0001). At 21 and 42 days, FGFR2 was also expressed on osteoblasts, fibroblasts and inside enlarged lacunae of cementocytes along with acute and chronic inflammatory cells (macrophages, plasma cells and neutrophils). At all periods and cells, FGFR2 expression was observed in the cell membrane and cytoplasm, but not in the nucleus.

CONCLUSION

In mice, FGFR2 was not expressed in tissues surrounding healthy teeth but was expressed in apical periodontitis, specifically in the membrane and cytoplasm of osteoblasts, fibroblasts, lacunae of cementocytes, and acute and chronic inflammatory cells (macrophages, plasma cells and neutrophils). Its expression was correlated with the size of the periapical lesions.

Fibroblast growth factor receptor 1 gene amplification and protein expression in human lung cancer

BACKGROUND

Targeting fibroblast growth factor receptor 1 (FGFR1) is a potential treatment for squamous cell lung cancer (SQCLC). So far, treatment decision in clinical studies is based on gene amplification. However, only a minority of patients have shown durable response. Furthermore, former studies have revealed contrasting results regarding the impact of FGFR1 amplification and expression on patient's prognosis.

AIMS

Here, we analyzed prevalence and correlation of FGFR1 gene amplification and protein expression in human lung cancer and their impact on overall survival. MATERIALS & METHODS: FGFR1 gene amplification and protein expression were analyzed by fluorescence in situ hybridization and immunohistochemistry (IHC) in 208 SQCLC and 45 small cell lung cancers (SCLC). Furthermore, FGFR1 protein expression was analyzed in 121 pulmonary adenocarcinomas (ACs). Amplification and expression were correlated to each other, clinicopathological characteristics, and overall survival.

RESULTS

FGFR1 was amplified in 23% of SQCLC and 8% of SCLC. Amplification was correlated to males (P = .027) but not to overall survival. Specificity of immunostaining was verified by cellular CRISPR/Cas9 FGFR1 knockout. FGFR1 was strongly expressed in 9% of SQCLC, 35% of AC, and 4% of SCLC. Expression was correlated to females (P = .0187) and to the absence of lymph node metastasis in SQCLC (P = .018) with no significant correlation to overall survival. Interestingly, no significant correlation between amplification and expression was detected.

DISCUSSION

FGFR1 gene amplification does not seem to correlate to protein expression.

CONCLUSION

We believe that patient selection for FGFR1 inhibitors in clinical studies should be reconsidered. Neither FGFR1 amplification nor expression influences patient's prognosis.

Genetic alteration profile of EGFR-mutant resected IIB-IIIA stage NSCLC and correlation to clinical outcomes

Background

Genetic alteration profile of epidermal growth factor receptor (EGFR) mutant resected non-small cell lung cancer (NSCLC) and its relationship with clinical outcomes remains to be illustrated and genetic biomarkers that can predict recurrence need to be figured out.

Methods

Clinicopathological and follow-up information were collected for 99 EGFR-mutant resected NSCLC. Tumor sections were collected for genetic alteration detection. Targeted next-generation sequencing (NGS) was performed to detect somatic mutations within each sample using a 285-gene panel on the Ion Torrent platform.

Results

Concurrent driver gene mutations were detected in 86 participants. Adjuvant therapy was a positive factor in disease-free survival (DFS) period, and patients receiving tyrosine kinase inhibitors (TKIs) gained the longest DFS. A total of 34 concurrent mutant driver genes were found. The median number of mutated driver genes for each sample was 2 (range, 0-12). TP53 and NOTCH1 were the most frequent concurrent mutant driver genes with rates of 53.54% and 25.25% respectively. The number of concurrent mutant genes did not have a significant effect on recurrence. Multivariable analysis found that mutations of ATM (P=0.021), KIT (P=0.002), FGFR2 (P<0.001), MET (P=0.015), PDGFRA (P=0.042), RB1 (P=0.006), and wildtype NOTCH1 (P=0.032), ERBB4 (P=0.012), FGFR3 (P=0.035) were independent risk factors for the recurrence of resected EGFR mutant NSCLC.

Conclusions

TP53 and NOTCH1 was the most common concurrent mutant driver gene. Mutations of ATM, KIT, FGFR2, MET, PDGFRA, RB1, and wildtype NOTCH1, ERBB4, FGFR3 were independent risk factors for the recurrence of resected EGFR mutant NSCLC.

Tumor-associated inflammatory microenvironment in non-small cell lung cancer: correlation with FGFR1 and TLR4 expression via PI3K/Akt pathway

The tumor-associated inflammatory microenvironment plays a pivotal role in human non-small cell lung cancer (NSCLC) development. FGFR1 and TLR4 involve in the regulation of inflammatory microenvironment of NSCLC.However, the relationship between the FGFR1 and TLR4 signaling and the mechanisms that involved in tumor-associated microenvironment are still unclear. We investigated the expression of FGFR1 and TLR4 in cancerous tissues and noncancerous lung tissues from 60 primary NSCLC patients using immunohistochemical staining. Three cell lines (A549, PC-9 and SK-MES-1) were used for in vitro studies. We demonstrated that the expression of FGFR1 and TLR4 was significantly correlated (r=0.504, p<0.05) in NSCLC tissues. We revealed that activation of FGFR1 and TLR4 pathways by specific signaling agonist increased Akt phosphorylation. Further results showed that FGFR1 and TLR4 regulated cell proliferation and migration and promoted the production of proinflammatory or immunosuppressive cytokines TNF-α and IL-6. Meanwhile, the PI3K inhibitor LY294002 rescued these changes. Taken together, our results indicate that the FGFR1 expression level is positively correlated with TLR4 expression level in human NSCLC tissues. The activation of FGFR1 and TLR4 in cancer cells contributes to inflammatory microenvironment via PI3K/Akt signaling and may make a significant contribution to the progression of human NSCLC.

Identification of differentially expressed genes and enriched pathways in lung cancer using bioinformatics analysis

Lung cancer is the leading cause of cancer‑associated mortality worldwide. The aim of the present study was to identify the differentially expressed genes (DEGs) and enriched pathways in lung cancer by bioinformatics analysis, and to provide potential targets for diagnosis and treatment. Valid microarray data of 31 pairs of lung cancer tissues and matched normal samples (GSE19804) were obtained from the Gene Expression Omnibus database. Significance analysis of the gene expression profile was used to identify DEGs between cancer tissues and normal tissues, and a total of 1,970 DEGs, which were significantly enriched in biological processes, were screened. Through the Gene Ontology function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, 77 KEGG pathways associated with lung cancer were identified, among which the Toll‑like receptor pathway was observed to be important. Protein‑protein interaction network analysis extracted 1,770 nodes and 10,667 edges, and identified 10 genes with key roles in lung cancer with highest degrees, hub centrality and betweenness. Additionally, the module analysis of protein‑protein interactions revealed that 'chemokine signaling pathway', 'cell cycle' and 'pathways in cancer' had a close association with lung cancer. In conclusion, the identified DEGs, particularly the hub genes, strengthen the understanding of the development and progression of lung cancer, and certain genes (including advanced glycosylation end‑product specific receptor and epidermal growth factor receptor) may be used as candidate target molecules to diagnose, monitor and treat lung cancer.

Pathological and Prognostic Impacts of FGFR2 Overexpression in Gastric Cancer: A Meta-Analysis

Fibroblast growth factor receptor-2 (FGFR2) protein expression by immunohistochemistry has been reported in up to 60% of patients with gastric cancer (GC). However, the clicopathological impacts of high FGFR2 expression have not been consistent among studies. We conducted this meta-analysis to evaluate the pathological and prognostic significance of FGFR2 overexpression in patients with GC. A systematic search of the electronic databases including PubMed, PMC, EMBASE, and Google Scholar was performed. From ten studies, 4,294 patients were included in the pooled analyses of odds ratios (ORs) with 95% confidence intervals (CIs) for pathological features and hazard ratios (HRs) with 95% CIs for overall survival according to the FGFR2 expression status. Compared with tumors showing low FGFR2 expression, GCs with FGFR2 overexpression revealed deeper depth of invasion (pT3-4) (OR = 2.63, 95% CI: 1.70-4.06, p < 0.0001), higher rate of lymph node metastasis (OR = 1.87, 95% CI: 1.31-2.67, p < 0.0001), and more advanced stage (III-IV) (OR = 1.78, 95% CI: 1.07-2.96, p = 0.03). In addition, patients with FGFR2-overexpressed GC showed significantly worse survival than those with FGFR2-low tumor (HR = 1.40, 95% CI: 1.25-1.58, p < 0.00001). In conclusion, this meta-analysis indicates that FGFR2 overexpression is associated with poor pathological features and prognosis in patients with GC.

Blocking FGFR4 exerts distinct anti-tumorigenic effects in esophageal squamous cell carcinoma

Background

The FGFR family can be activated by FGFs and plays important roles in regulating cell growth, differentiation, migration, and angiogenesis. Recent studies have suggested that FGFR4 could regulate several processes, including tumor progression. Esophageal squamous cell carcinoma (ESCC) is a malignancy with high global occurrence. However, the molecule mechanism and the potential roles of FGFR4 in ESCC remain unknown.

Methods

Immunohistochemistry and Western blotting were used to detect FGFR4 expression in ESCC samples and cell lines. Cell counting kit‐8, and clonogenic, transwell, flow cytometric, and tumor xenograft in nude mice assays were utilized to determine the effect of blocking FGFR4 in proliferation, invasion, migration, and apoptosis of ESCC cells.

Results

FGFR4 is frequently overexpressed in ESCC tissue and cell lines. in vitro assays have shown that blocking FGFR4 by a specific blocker, H3B‐6527, significantly decreases proliferation, invasion, and migration, and alters epithelial‐mesenchymal transition markers in ESCC cells. In addition, FGFR4 blockade is associated with the induction of apoptosis and affects PI3K/Akt and MAPK/ERK pathways. Moreover, FGFR4 blockade could significantly inhibit the growth of xenograft tumors in vivo.

Conclusion

Our findings suggest that blocking FGFR4 significantly suppresses the malignant behaviors of ESCC and indicate that FGFR4 is a potential target for the treatment of ESCC.

High Affinity Promotes Internalization of Engineered Antibodies Targeting FGFR1

Fibroblast growth factor receptor 1 (FGFR1) is a plasma membrane protein that transmits signals from the extracellular environment, regulating cell homeostasis and function. Dysregulation of FGFR1 leads to the development of human cancers and noncancerous diseases. Numerous tumors overproduce FGFR1, making this receptor a perspective target for cancer therapies. Antibody-drug conjugates (ADCs) are highly potent and selective anticancer agents. ADCs are composed of antibodies (targeting factors) fused to highly cytotoxic drugs (warheads). The efficiency of ADC strategy largely depends on the internalization of cytotoxic conjugate into cancer cells. Here, we have studied an interplay between affinity of anti-FGFR1 antibodies and efficiency of their cellular uptake. We have developed a unique set of engineered anti-FGFR1 antibodies that bind the same epitope in the extracellular part of FGFR1, but with different affinities. We have demonstrated that these antibodies are effectively taken up by cancer cells in the FGFR1-dependent manner. Interestingly, we have found that efficiency, defined as rate and level of antibody internalization, largely depends on the affinity of engineered antibodies towards FGFR1, as high affinity antibody displays fastest internalization kinetics. Our data may facilitate design of therapeutically relevant targeting molecules for selective treatment of FGFR1 overproducing cancers.

Beyond EGFR and ALK: targeting rare mutations in advanced non-small cell lung cancer

Lung cancer remains the leading cause of cancer-related death in men and women, despite its constantly declining rates in incidence and mortality in the developed world. The past decade has witnessed an unprecedented rise in the development of molecular targeted therapies in various types of tumors. In non-small cell lung cancer (NSCLC), the greatest paradigm shift is the implementation of EGFR and ALK tyrosine kinase inhibitors in the first line and subsequent lines of therapy, with impressive results. Though less frequent than the molecular alterations in the aforementioned genes, a number of aberrations in potential oncogenic drivers has been discovered, namely mutations in the genes KRAS, BRAF, HER2, PI3KCA and DDR2, ROS1 and RET rearrangements and MET, HER2 and FGFR1 gene amplifications. A great number of clinical trials are currently underway, evaluating agents specifically designed to target these alterations, with mixed results so far. The greatest cumulative benefit offered by these trials is that, despite their success or failure in their objective goals, they have provided us with a better understanding of the complexity of the molecular intracellular processes, necessitating thus the accurate interpretation of the preclinical data in order to appropriately select the patients that may derive benefit from targeted treatment strategies.

PAN-cancer analysis of S-phase enriched lncRNAs identifies oncogenic drivers and biomarkers

Despite improvement in our understanding of long noncoding RNAs (lncRNAs) role in cancer, efforts to find clinically relevant cancer-associated lncRNAs are still lacking. Here, using nascent RNA capture sequencing, we identify 1145 temporally expressed S-phase-enriched lncRNAs. Among these, 570 lncRNAs show significant differential expression in at least one tumor type across TCGA data sets. Systematic clinical investigation of 14 Pan-Cancer data sets identified 633 independent prognostic markers. Silencing of the top differentially expressed and clinically relevant S-phase-enriched lncRNAs in several cancer models affects crucial cancer cell hallmarks. Mechanistic investigations on SCAT7 in multiple cancer types reveal that it interacts with hnRNPK/YBX1 complex and affects cancer cell hallmarks through the regulation of FGF/FGFR and its downstream PI3K/AKT and MAPK pathways. We also implement a LNA-antisense oligo-based strategy to treat cancer cell line and patient-derived tumor (PDX) xenografts. Thus, this study provides a comprehensive list of lncRNA-based oncogenic drivers with potential prognostic value.

Although we know lncRNAs play a role in cancer, the identification of clinically relevant and functional lncRNAs is lacking. Here, the authors identify 633 prognostic markers, 570 S-phase cancer-associated lncRNAs, and show SCAT7 regulates FGF/FGFR and PI3K/AKT/MAPK pathways via interaction with hnRNPK/YBX1 complexes.

Expression Analysis of Angiogenesis-Related Genes in Bulgarian Patients with Early-Stage Non-Small Cell Lung Cancer

Aims and background

Angiogenesis is a key process in the early stages of tumor development. In this study we aimed to evaluate the expression of a panel of angiogenesis-related genes in a group of Bulgarian patients with early-stage non-small cell lung cancer (NSCLC).

Methods and study design

We analyzed the expression of 84 genes associated with the angiogenic process in 12 NSCLCs of two histological subtypes: 7 adenocarcinomas and 5 squamous cell carcinomas. Eight peripheral nontumorous tissues were used as controls. We performed real-time PCR on pathway-specific gene arrays (SABiosciences).

Results

Our pilot study identified upregulated genes in early-stage NSCLC including growth factors (TGFA and EFNA3), the adhesion molecule THBS2, cytokines and chemokines (MDK, CXCL9, CXCL10), and the serine protease PLAU. Several genes showed downregulation including one growth factor (FIGF), the receptors for growth factors TEK and S1PR1 as well as adhesion molecules (COL4A3 and CDH5), the cytokine IL6, the matrix protein LEP and the transcription factor NOTCH4. The study demonstrated deregulated genes specific for the two histological subtypes including the transcription factor HAND2, which was overexpressed in squamous cell carcinomas but not adenocarcinomas.

Conclusions

Despite the limited number of patients, our results demonstrated the potential of angiogenesis-related genes as biomarkers in the early stages of NSCLC development. Free full text available at www.tumorionline.it

FGF7/FGFR2 signal promotes invasion and migration in human gastric cancer through upregulation of thrombospondin-1

Fibroblast growth factor 7 (FGF7) is a mesenchyme-specific heparin-binding growth factor that binds FGF receptor 2 (FGFR2) to regulate numerous cellular and physiological processes. FGF7/FGFR2 signal is associated with gastric cancer progression. In the present study, we investigated the molecular mechanism by which FGF7/FGFR2 promotes invasion and migration in human gastric cancer. We first demonstrated that increased FGFR2 expression in human gastric cancer tissues was significantly associated with tumor depth and clinical stage in human gastric cancer tissues. Thrombospondin 1 (THBS1) is an extracellular glycoprotein that plays multiple roles in cell-matrix and cell-cell interactions. Increased expression of THBS1 significantly correlated with tumor differentiation. FGFR2 and THBS1 expression were both increased in cancer tissues as compared with adjacent normal tissues and their expression was positively correlated. In vitro, FGF7 stimulation of cell invasion and migration was partially suppressed by the FGFR2 knockdown. In addition, FGF7/FGFR2 upregulated THBS1, and cell invasion and migration were decreased by knockdown of THBS1. Furthermore, the PI3K/Akt/mTOR signaling pathway was predominantly responsible for FGF7/FGFR2-induced THBS1 upregulation. Taken together, our data suggest that FGF7/FGFR2/THBS1 is associated with the regulation of invasion and migration in human gastric cancer.

Fibroblast Growth Factor Receptor 1 (FGFR1), Partly Related to Vascular Endothelial Growth Factor Receptor 2 (VEGFR2) and Microvessel Density, is an Independent Prognostic Factor for Non-Small Cell Lung Cancer

Background

This study aimed to explore the correlation between FGFR1 and clinical features, including survival analysis and the promotion of angiogenesis by fibroblast growth factor receptor 1 (FGFR1) and vascular endothelial growth factor receptor 2 (VEGFR2). FGFR1 gene amplification has been found in non-small cell lung cancer (NSCLC). However, the prognostic value of FGFR1 and the correlation between FGFR1 and clinical features are still controversial.

Material/Methods

A total of 92 patients with NSCLC who underwent R0 resection between July 2006 and July 2008 were enrolled in the study. The expression of FGFR1, VEGFR2, and CD34 was detected by immunohistochemistry. The correlations between the aforementioned markers and the patients’ clinical features were analyzed by the chi-square test. The impact factors of prognosis were evaluated by Cox regression analyses.

Results

The expression ratios of FGFR1 and VEGFR2 were 26.1% and 43.4%, respectively. The intensity of FGFR1 expression was related to VEGFR2 and histopathology. To some extent, the average microvessel density (MVD) had correlation to the expression of FGFR1 and VGEFR2. The pathological stages III–IV and high expression of FGFR1 were found to be independent prognostic factors.

Conclusions

The expression intensity of FGFR1 and VEGFR2 was associated with MVD, and the expression of FGFR1 is one of the independent prognostic indicators for NSCLC.

Identification of feature genes for smoking-related lung adenocarcinoma based on gene expression profile data

This study aimed to identify the genes and pathways associated with smoking-related lung adenocarcinoma. Three lung adenocarcinoma associated datasets (GSE43458, GSE10072, and GSE50081), the subjects of which included smokers and nonsmokers, were downloaded to screen the differentially expressed feature genes between smokers and nonsmokers. Based on the identified feature genes, we constructed the protein-protein interaction (PPI) network and optimized feature genes using closeness centrality (CC) algorithm. Then, the support vector machine (SVM) classification model was constructed based on the feature genes with higher CC values. Finally, pathway enrichment analysis of the feature genes was performed. A total of 213 down-regulated and 83 up-regulated differentially expressed genes were identified. In the constructed PPI network, the top ten nodes with higher degrees and CC values included ANK3, EPHA4, FGFR2, etc. The SVM classifier was constructed with 27 feature genes, which could accurately identify smokers and nonsmokers. Pathways enrichment analysis for the 27 feature genes revealed that they were significantly enriched in five pathways, including proteoglycans in cancer (EGFR, SDC4, SDC2, etc.), and Ras signaling pathway (FGFR2, PLA2G1B, EGFR, etc.). The 27 feature genes, such as EPHA4, FGFR2, and EGFR for SVM classifier construction and cancer-related pathways of Ras signaling pathway and proteoglycans in cancer may play key roles in the progression and development of smoking-related lung adenocarcinoma.

The coexpression and prognostic significance of c-MET, fibroblast growth factor receptor 2, and human epidermal growth factor receptor 2 in resected gastric cancer: a retrospective study

Molecular-targeted therapy against tyrosine kinase receptors (RTKs) plays an important role in gastric cancer (GC) treatment. Understanding the correlation between RTK coexpression could better guide clinical drug use. In the present study, the coexpression status of c-MET, fibroblast growth factor receptor 2 (FGFR2), and human epidermal growth factor receptor 2 (HER2) in human GC and their clinical significance in clinical therapy were explored. Immunohistochemical (IHC) staining, quantitative real-time polymerase chain reaction and fluorescent in situ hybridization were performed in 143 cases of GC who had undergone gastrectomy without preoperative chemoradiotherapy. Their association with clinicopathological features and clinical prognosis was analyzed. The frequencies of c-MET, FGFR2, and HER2 overexpression were 47.6% (68/143), 34.3% (49/143), and 10.5% (15/143), respectively. In the RTK coexpression study, 30.1% of patients (43/143) were positive for only one RTK, 25.8% (37/143) were positive for two RTKs, 3.5% (5/143) had triple-positive status, and 40.6% (58/143) had triple-negative status. In survival analysis, the overexpression of c-MET, FGFR2, and HER2 were significantly associated with overall survival (OS) (P=0.018, 0.004, and 0.049, respectively). In coexpression analysis, patients with triple-positive GC had the poorest OS (P=0.013). In conclusion, RTK coexpression is significantly associated with poor clinical outcome in GC.

Anti-cancer effects of baicalein in non-small cell lung cancer in-vitro and in-vivo

Background

Baicalein is a widely used Chinese herbal medicine derived from Scutellaria baicalenesis, which has been traditionally used as anti-inflammatory and anti-cancer therapy. In this study we examined the anti-tumour pathways activated following baicalein treatment in non-small cell lung cancer (NSCLC), both in-vitro and in-vivo.

Methods

The effect of baicalein treatment on H-460 cells in-vitro was assessed using both BrdU assay (cell proliferation) and High Content Screening (multi-parameter apoptosis assay). A xenograft nude mouse model was subsequently established using these cells and the effect of baicalein on tumour growth and survival assessed in-vivo. Tumours were harvested from these mice and histological tissue analysis carried out. VEGF, 12-lipoxygenase and microvessel density (CD-31) were assessed by immunohistochemistry (IHC), while H and E staining was carried out to assess mitotic index. Gene expression profiling was carried out on corresponding RNA samples using Human Cancer Pathway Finder Arrays and qRT-PCR, with further gene expression analysis carried out using qRT-PCR.

Results

Baicalein significantly decreased lung cancer proliferation in H-460 cells in a dose dependent manner. At the functional level, a dose-dependent induction in apoptosis associated with decreased cellular f-actin content, an increase in nuclear condensation and an increase in mitochondrial mass potential was observed. Orthotopic treatment of experimental H-460 tumours in athymic nude mice with baicalein significantly (p < 0.05) reduced tumour growth and prolonged survival. Histological analysis of resulting tumour xenografts demonstrated reduced expression of both 12-lipoxygenase and VEGF proteins in baicalein-treated tumours, relative to untreated. A significant (p < 0.01) reduction in both mitotic index and micro-vessel density was observed following baicalein treatment. Gene expression profiling revealed a reduction (p < 0.01) in both VEGF and FGFR-2 following baicalein treatment, with a corresponding increase (p < 0.001) in RB-1.

Conclusion

This study is the first to demonstrate efficacy of baicalein both in-vitro and in-vivo in NSCLC. These effects may be mediated in part through a reduction in both cell cycle progression and angiogenesis. At the molecular level, alterations in expression of VEGF, FGFR-2, and RB-1 have been implicated, suggesting a molecular mechanism underlying this in-vivo effect.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2740-0) contains supplementary material, which is available to authorized users.

FGFR1, 2 and 3 protein overexpression and molecular aberrations of FGFR3 in early stage non-small cell lung cancer

This study aimed to determine protein expression levels of fibroblast growth factor receptors (FGFR) 1, 2 and 3 in early stage non‐small cell lung cancer (NSCLC). Additionally, a screen to define the frequency of FGFR3‐TACC3 translocation and FGFR3 amplification was performed. Archived tissues from 653 NSCLC samples (adenocarcinoma (AC), squamous cell carcinoma (SCC) and large cell carcinoma (LCC)) were analysed with immunohistochemistry (IHC) for expression of FGFR1, 2 and 3. Expression levels of FGFR1, 2 and 3 were correlated with clinicopathological features. The presence of FGFR3‐TACC3 translocation was detected by RT‐PCR and FGFR3 amplification was detected by fluorescence in situ hybridization. FGFR1, 2 and 3 proteins were highly expressed in 64 (10.6%), 76 (12.9%) and 20 (3.3%) NSCLC tumour samples, respectively. Protein expression of FGFR1 was significantly related to worse overall survival in NSCLC. Furthermore, FGFR1 protein expression was associated with light smoking and histological subtype (AC), FGFR2 protein expression with female gender, younger age, histological subtype (AC) and lower tumour stage, and FGFR3 protein was significantly overexpressed in tumours of older patients and SCC histology. The FGFR3‐TACC3 fusion was detected in 3.0% (6/200) of NSCLC samples and the FGFR3 gene was amplified in 4.7% of IHC positive NSCLC samples (2/43). FGFR1, 2 and 3 proteins are expressed in a high number of early stage NSCLC and FGFR1 protein expression may serve as a prognostic biomarker. Recurrent translocations and amplifications in FGFR3 can be found in NSCLC. This study shows that FGFR family members are frequently aberrant in NSCLC and could be interesting therapeutic targets for the treatment of NSCLC.

Peptidomimetic suppresses proliferation and invasion of gastric cancer cells by fibroblast growth factor 2 signaling cascade blockage

Fibroblast growth factor 2 (FGF2) is closely involved in a variety of tumors, including gastric cancer (GC). FGF2 inhibitors exert good antitumor activity, but no FGF2 inhibitor has been employed for clinical use. To obtain a low-toxicity, stable peptidomimetic (called P29) target to FGF2, the affinity between P29 and FGF2 was detected by surface plasmon resonance. The stability of P29 was measured by high performance liquid chromatography. MTT assay and transwell assay were used to access the proliferative and invasive ability of GC cells, respectively. Western blot assay and flow cytometric analysis were applied to study the mechanism of P29. P29 possessed high affinity with FGF2 and a longer half-life in vitro. P29 suppressed the FGF2-induced proliferation of GC cells. It also inhibited the phosphorylation of FRS2, ERK1/2, and AKT triggered by FGF2 in GC. In addition, P29 blocked GC cell transformation from the G1/G0 phase to the S phase and weakened the invasive capability of GC cells. In this paper, we present a novel FGF2 inhibitor that could exert improved anticancer effect in GC in vitro.

Amplification of FGFR1 gene and expression of FGFR1 protein is found in different histological types of lung carcinoma

Although lung cancer continues to be the leading cause of cancer-related death, accurate diagnosis followed by personalized treatment is expected to raise the 5-year survival rate. Targeted therapies are now in routine clinical use, in particular for lung adenocarcinoma (ADC). Fibroblast growth factor receptor 1 (FGFR1) has recently emerged as a molecular target, especially in squamous cell/epidermoid carcinoma (SQC) of the lung. This paper evaluates FGFR1 expression and gene copy number in adenocarcinomas, squamous cell carcinomas, pleomorphic carcinomas (PLEOMC) and adenosquamous carcinomas (ADSQC) of the lung and also explores the epithelial-mesenchymal transition (EMT) pathway. We studied 76 lung carcinomas: 34 ADC, 24 SQC, 10 PLEOMC and 8 ADSQC. FGFR1 expression was evaluated by immunohistochemistry and gene amplification by fluorescence in situ hybridization (FISH). Higher FGFR1 protein expression was observed in all tumour types compared to non-tumour tissue. FGFR1 expression was higher in ADC and PLEOMC than in SQC. We found a tendency to higher expression in ADC than in SQC and significantly higher expression in PLEOMC than in other histological subtypes. FISH-based amplification of FGFR1 was identified in 15 (20 %) lung carcinomas: 5 (15 %) ADC, 5 (21 %) SQC, 3 (30 %) PLEOMC and 2 (25 %) ADSQC. Amplification was more frequent in SQC without significant differences. FGFR1 protein is expressed in the majority of lung carcinomas, though it is higher in ADC and PLEOMC (the latter may reflect the importance of FGFR1 control of the EMT pathway). FGFR1 amplification was identified in all types of lung carcinoma. Although FGFR1 is most frequently amplified in SQC, other histological types merit assessment of FGFR1 amplification, in order to select patients that might benefit from targeted therapy.

Rapid Identification of FGFR2 Gene Mutations in Taiwanese Patients With Endometrial Cancer Using High-resolution Melting Analysis

OBJECTIVES

Mutations in fibroblast growth factor receptor 2 (FGFR2) gene have been reported in endometrial cancer and mutant FGFR2 has been pointed out as a potential therapeutic target. The aim of the current study was to use a high-resolution melting (HRM) analysis to identify FGFR2 hotspot mutations and to investigate the occurrence of these mutations in the Taiwanese population with endometrial cancer.

DESIGN AND METHODS

HRM analysis was designed to characterize the FGFR2 hotspot mutations. DNAs were extracted from 72 cases of fresh-frozen endometrial cancer tissues for FGFR2 mutational analysis by HRM analysis. The 6 exons of FGFR2 were screened by HRM analysis. All results were confirmed by direct sequencing.

RESULTS

We have identified the 6 reported mutations in the FGFR2 gene. The mutation c.879C>T (p.Q289P) was first reported in endometrial cancer. Each mutation could be readily and accurately identified in the difference plot curves. The frequency of FGFR2 hotspot mutations is 9.7% (7/72) in patients with endometrial cancer in the Taiwanese population.

CONCLUSIONS

HRM analysis is rapid, feasible, and a reliable diagnostic method for the detection of FGFR2 mutations in a clinical setting. Our results indicated the prevalence of FGFR2 mutational status in the Taiwanese population with endometrial cancer.

KIAA1522 is a novel prognostic biomarker in patients with non-small cell lung cancer

Nowadays, no robust biomarkers have been applied to clinical practice to provide prognostic evaluation of non-small cell lung cancer (NSCLC). This study aims to identify new potential prognostic biomarkers for NSCLC. In the present work, KIAA1522 is screened out from two independent GEO datasets as aberrantly up-regulated gene in NSCLC tissues. We evaluate KIAA1522 expression immunohistochemically in 583 NSCLC tissue samples and paired non-tumor tissues. KIAA1522 displays stronger staining in NSCLC cases than in adjacent normal lung tissues. Importantly, patients with KIAA1522 overexpression had a significantly shorter overall survival compared to those with low expression (P < 0.00001). Multivariate Cox regression analyses show that KIAA1522 is an independent prognostic indicator, even for early-stage NSCLCs (P = 0.00025, HR = 2.317, 95%CI: 1.477–3.635). We also found that high expression of KIAA1522 is a significant risk factor for decreased overall survival of the patients who received platinum-based chemotherapy. Gene set enrichment analysis (GSEA) and functional studies reveal that KIAA1522 is associated with oncogenic KRAS pathways. Taken together, high expression of KIAA1522 can be used as an independent biomarker for predication of poor survival and platinum-resistance of NSCLC patients, and aberrant KIAA1522 might be a new target for the therapy of the disease.

Cellular and molecular biology of small cell lung cancer: an overview

Although the incidence of small cell lung cancer (SCLC) has declined during the past 30 years, it remains a frustrating disease to research and treat. Numerous attempts to enhance the anti-tumor effects of traditional chemotherapy for SCLC have not been successful. For any tumor to become cancerous, various genetic mutations and biologic alterations must occur in the cell that, when combined, render it a malignant neoplasm. New and novel therapies based on understanding these mechanisms of transformation are needed. Herein we provide an in-depth view of some of the genomic alterations in SCLC that have emerged as potential targets for therapeutic intervention.

Fibroblast growth factor receptor 2 is associated with poor overall survival in clear cell carcinoma of the ovary and may be a novel therapeutic approach

OBJECTIVE

We previously found that gene and protein expression of fibroblast growth factor receptor (FGFR) 2 were increased in ovarian clear cell carcinoma (CCC); here, we examined FGFR2 expression in CCC tumor tissues and its correlation with clinical parameters. We also analyzed the effect of an FGFR inhibitor on the growth of CCC cells to investigate whether FGFR2 could be a therapeutic target for this disease.

METHODS

We analyze the protein expression of FGFR2 by immunohistochemical staining in CCC from 112 patients and evaluated the association of these molecular parameters with clinical outcome. We treated the 11 CCC cell lines with an FGFR inhibitor, and then assessed cell viability, the expression of protein in FGFR2 signaling pathway, and cell cycle distribution.

RESULTS

The expressions of FGFR2 were found in 96% of CCC. The 5-year survival rate for patients with a moderate or strong expression of FGFR2 was significantly lower than that for those with an absent or poor expression of FGFR2 (54% vs 79%). Multivariable analysis revealed that FGFR2 expression and disease stage were independent prognostic factors. The FGFR inhibitor effectively suppressed the growth of CCC cells with induction of G1 cell cycle arrest and down-regulated the expression of phosphorylated Akt and phosphorylated ERK.

CONCLUSIONS

FGFR2 is an important biomarker predictive of patient outcome and is a potential target for CCC. Further study is warranted for FGFR inhibitor to treat CCC.

Prognostic Value of Basic Fibroblast Growth Factor (bFGF) in Lung Cancer: A Systematic Review with Meta-Analysis

Background

Basic fibroblast growth factor (bFGF) is known to stimulate angiogenesis and thus to influence the proliferation, migration and survival of tumor cells. Many studies examined the relationship between human bFGF overexpression and survival in lung cancer patients, but the results have been mixed. To systematically summarize the clinical prognostic function of bFGF in lung cancer, we performed this systematic review with meta-analysis.

Method

Studies were identified by an electronic search of PubMed, EMBASE, China National Knowledge Infrastructure and Wanfang databases, including publications prior toAugust 2014. Pooled hazard ratios (HR) for overall survival (OS) were aggregated and quantitatively analyzed by meta-analysis.

Results

Twenty-two studies (n = 2154) were evaluated in the meta-analysis. Combined HR suggested that bFGF overexpression had an adverse impact on survival of patients with lung cancer(HR = 1.202,95%CI, 1.022–1.382). Our subgroup analysis revealed that the combined HR evaluating bFGF expression on OS in operable non-small cell lung cancer (NSCLC) was 1.553 (95%CI, 1.120–1.986); the combined HR in small cell lung cancer (SCLC) was 1.667 (95%CI, 1.035–2.299). There was no significant impact of bFGF expression on survival in advanced NSCLC.

Conclusion

This meta-analysis showed that bFGF overexpression is a potential indicator of worse prognosis for patients with operable NSCLC and SCLC, but is not associated with outcome in advanced NSCLC. The data suggests that high bFGF expression is highly related to poor prognosis. Nevertheless,more high-quality studies should be performed in order to provide additional evidence for the prognostic value of bFGF in lung cancer.

ZEB1 expression is associated with prognosis of intrahepatic cholangiocarcinoma

Background/Aim

Intrahepatic cholangiocarcinoma (ICC) is one of the most aggressive malignant tumours, so the identification of molecular targets for ICC is an important issue. Zinc finger E-box binding homeobox 1 (ZEB1) is a key inducer of epithelial–mesenchymal transition (EMT). The aim of the present study was to clarify the clinical significance of ZEB1 in ICC and the associations between ZEB1 expression and EMT-related proteins.

Methods

We immunohistochemically examined the expression of EMT-related proteins, namely ZEB1, vimentin and E-cadherin, in ICC specimens from 102 patients. The clinicopathological and prognostic values of these markers were evaluated.

Results

ZEB1 and vimentin were expressed in 46.1% and 43.1% of tumours, respectively, and E-cadherin expression was lost in 44.1% of tumours. ZEB1 expression showed a significant inverse correlation with E-cadherin expression (p=0.004) and a positive correlation with vimentin expression (p=0.022). Altered expression of ZEB1 was associated with aggressive tumour characteristics, including advanced tumour stage (p=0.037), undifferentiated-type histology (p=0.017), lymph node metastasis (p=0.024) and portal vein invasion (p=0.037). Moreover, overall survival rates were significantly lower for patients with high ZEB1 expression than for patients with low ZEB1 expression (p=0.027). Kaplan–Meier analysis also identified E-cadherin expression (p=0.041) and vimentin expression (p=0.049) as prognostic indicators for overall survival.

Conclusions

ZEB1 expression is associated with tumour progression and poor prognosis in patients with ICC through positive correlations with vimentin and negative correlations with E-cadherin. ZEB1 expression is associated with a poor prognosis and might be an attractive target for the treatment of ICC.

Circulating Thrombospondin-2 and FGF-2 in Patients with Advanced Non-small Cell Lung Cancer: Correlation with Survival

Thrombospondin-2 (TSP-2) is an endogenous negative regulator of vascularization in human cancer. TSP-2 regulates angiogenesis through binding and sequestration of the proangiogenic fibroblast growth factor-2 (FGF-2). However, it is unclear whether TSP-2 and FGF-2 are related to prognosis in non-small cell lung cancer (NSCLC). To study this issue, we measured serum (Elisa) levels of TSP-2 and FGF-2 in 40 NSCLC patients (before chemotherapy) and 22 healthy subjects. Both TSP-2 and FGF-2 concentrations were elevated in the NSCLC group compared with control (TSP-2: 26.72±8.00 vs. 18.64±5.50 ng/ml, p=0.002; FGF-2: 11.90±5.80 vs. 7.26±3.90 pg/ml, p=0.01). Receiver-operating characteristic (ROC) curves were applied to find the cut-off serum levels of TSP-2 and FGF-2 (NSCLC vs. healthy: TSP-2=15.09 ng/ml, FGF-2=2.23 pg/ml). Patients before treatment with the TSP-2 level<24.15 ng/ml had a median survival of 23.7 months, but those with TSP-2>24.15 ng/ml had only 9 months' median survival (p=0.007). Patients with FGF-2 level>11.21 pg/ml had significantly shorter survival than patients with FGF-2<11.21 pg/ml (7.5 months vs. 16 months, p=0.034). We conclude that NSCLC patients have higher serum concentrations of TSP-2 and FGF-2 than healthy people. High levels of TSP-2 and FGF-2 may predict worse survival.

High Expression of FGFR4 Enhances Tumor Growth and Metastasis in Nasopharyngeal Carcinoma

Background: FGF receptor (FGFR) family can be activated by FGFs and play important roles in regulating cell growth, differentiation, migration and angiogenesis. Recent studies suggested that FGFR4 could regulate several processes including tumor progression. Nasopharyngeal carcinoma (NPC) is a malignancy with a high occurrence in Southeast Asia and Southern China. However, the molecule mechanism and the potential roles of FGFR4 in NPC remain unknown

Methods: Immunohistochemistry and western blot were used to investigate the expression of FGFR4 in NPC samples. Then we used statistical analysis to evaluate the diagnostic value and the associations of FGFR4 expression with clinical parameters. In vitro studies, the effects of FGFR4 on proliferation and migration of NPC cell line CNE2 were measured by the starvation-refeeding experiment, CCK8 assay, wounding healing assay and transwell migration assay. The changes of the epithelial-mesenchymal transition (EMT) markers in CNE2 cells after knocking down the expression of FGFR4 were measured by Western blot and immunofluorescence analysis.

Results: FGFR4 was overexpressed in NPC as compared with the inflammatory tissues. High expression of FGFR4 was correlated with Ki67 expression, clinical stages and prognosis in NPC patients (P<0.05).While in vitro, the upregulation of FGFR4 was accompanied with CNE2 cells released from serum starvation. Moreover, it could increase cell proliferation and migration by regulating EMT markers in CNE2 cells.

Conclusion: Our data suggested that FGFR4 might induce NPC progression and act as a potential therapeutic target in NPC.

Expression pattern of FGFR2, Grb2 and Plcγ1 acts as a novel prognostic marker of recurrence recurrence-free survival in lung adenocarcinoma

Lung adenocarcinoma is characterized by complex biology involving alterations at the genomic and protein expression levels. FGFR2 mutation and/or amplification are key drivers of disease progression and drug resistance in lung adenocarcinoma patients. These genetic alterations drive oncogenic downstream signalling due to the deregulated activity of the receptor. We have previously reported that wild type FGFR2 provides a binding site for which two proteins, Grb2 and Plcγ1, compete in a concentration-dependent manner. Metastasis and invasion ensue when Plcγ1 prevails on the receptor giving rise to oncogenic outcome in the absence of gene mutation/deletion. The effect of this signalling mechanism on FGFR2-driven lung adenocarcinoma has not previously been considered. In this study we show that fluctuation in the combinatorial expression levels of FGFR2, Grb2 and Plcγ1 modulates cell invasive properties, tumor formation and is linked to recurrence-free survival in 150 lung adenocarcinoma patients. High levels of expression of FGFR2 and Plcγ1 in a low background of Grb2 significantly correlates with poor prognosis. On the other hand, low levels of expression of FGFR2 and Plcγ1 in a high background of Grb2 correlates with favourable prognosis. This study defines the expression pattern of FGFR2, Plcγ1 and Grb2 as a novel prognostic marker in human lung adenocarcinoma. Thus, consideration of the Grb2 and Plcγ1-mediated mechanism of FGFR2 regulation will enhance the therapeutic targeting of aberrant FGFR2 activity to provide the much-needed improvement to the treatment regimen of this high mortality disease.

Expression of fibroblast growth factor receptor 1, fibroblast growth factor 2, phosphatidyl inositol 3 phosphate kinase and their clinical and prognostic significance in early and advanced stage of squamous cell carcinoma of the lung

AIM

Non-small cell lung carcinoma is the leading cause of cancer related to death in the world. Squamous cell lung carcinoma (SqCLC) is the second most frequent histological subtype of lung carcinomas. Recently, growth factors, growth factor receptors, and signal transduction system-related gene amplifications and mutations are extensively under investigation to estimate the prognosis and to develop individualized therapies in SqCLC. In this study, besides the signal transduction molecule phosphatidyl inositol-3-phosphate kinase (IP3K) p110α, we explored the expressions of fibroblast growth factor 2 (FGF2) and receptor-1 (FGFR1) in tumor tissue and also their clinical and prognostic significance in patients with early/advanced SqCLC.

MATERIALS AND METHODS

From 2005 to 2013, 129 patients (23 early, 106 advanced disease) with a histopathological SqCLC diagnosis were selected from the hospital files of Cukurova University Medical Faculty for this study. Two independent pathologists evaluated FGFR1, FGF2, and PI3K (p110α) expressions in both tumor and stromal tissues from 99 of the patients with sufficient tissue samples, using immunohistochemistry. Considering survival analysis separately for patients with both early and advanced stage diseases, the relationship between the clinical features of the patients and expressions were evaluated by univariate and multivariate analyses.

RESULTS

FGFR1 expression was found to be low in 59 (60%) patients and high in 40 (40%) patients. For FGF2; 12 (12%) patients had high, 87 (88%) patients had low expression and for IP3K; 31 (32%) patients had high and 66 (68%) patients had low expressions. In univariate analysis, overall survival (OS) was significantly associated with stage of the disease and the performance status of the patient (P<0.0001 and P<0.001). There was no significant difference in OS of the patients with either low or high expressions of FGFR1, FGF2, and IP3K. When the patients with early or advanced stage disease were separately taken into consideration, the relationship did not differ, either. Any of FGFR1, FGF2 or IP3K expressions was not found predictive for the treatment of early or advanced staged patients. On the other hand, the expressions of both FGFR1 and FGF2 were significantly different with respect to smoking, scar of tuberculosis and scar of radiotherapy (P=0.002; P=0.06 and P=0.05, respectively).

DISCUSSION

There has not been identified an effective individualized treatment for SqCLC yet. Therefore, in order to be able to develop such a treatment in the future, it is essential to identify the genetic abnormalities that are responsible for the biological behaviors and carcinogenesis of SqCLC. Although we could not show the prognostic and predictive significance of FGFR1, FGF2 and IP3K expressions in SqCLC, we determined the expression rates of FGFR1, FGF2 and IP3K as a reference for Turkish patients. In conclusion, we want to put some emphasis on the fact that, pulmonary fibrosis which is a late complication of radiotherapy at stage III disease, and the scar of tuberculosis could be associated with FGFR1 and FGF2 expressions.

Fibroblast Growth Factor Receptor 1 and Related Ligands in Small-Cell Lung Cancer

INTRODUCTION

Small-cell lung cancer (SCLC) accounts for 15% of all lung cancers and has been understudied for novel therapies. Signaling through fibroblast growth factors (FGF2, FGF9) and their high-affinity receptor has recently emerged as a contributing factor in the pathogenesis and progression of non-small-cell lung cancer. In this study, we evaluated fibroblast growth factor receptor 1 (FGFR1) and ligand expression in primary SCLC samples.

METHODS

FGFR1 protein expression, messenger RNA (mRNA) levels, and gene copy number were determined by immunohistochemistry (IHC), mRNA in situ hybridization, and silver in situ hybridization, respectively, in primary tumors from 90 patients with SCLC. Protein and mRNA expression of the FGF2 and FGF9 ligands were determined by IHC and mRNA in situ hybridization, respectively. In addition, a second cohort of 24 SCLC biopsy samples with known FGFR1 amplification by fluorescence in situ hybridization was assessed for FGFR1 protein expression by IHC. Spearman correlation analysis was performed to evaluate associations of FGFR1, FGF2 and FGF9 protein levels, respective mRNA levels, and FGFR1 gene copy number.

RESULTS

FGFR1 protein expression by IHC demonstrated a significant correlation with FGFR1 mRNA levels (p < 0.0001) and FGFR1 gene copy number (p = 0.03). The prevalence of FGFR1 mRNA positivity was 19.7%. FGFR1 mRNA expression correlated with both FGF2 (p = 0.0001) and FGF9 (p = 0.002) mRNA levels, as well as with FGF2 (p = 0.01) and FGF9 (p = 0.001) protein levels. There was no significant association between FGFR1 and ligands with clinical characteristics or prognosis. In the second cohort of specimens with known FGFR1 amplification by fluorescence in situ hybridization, 23 of 24 had adequate tumor by IHC, and 73.9% (17 of 23) were positive for FGFR1 protein expression.

CONCLUSIONS

A subset of SCLCs is characterized by potentially activated FGF/FGFR1 pathways, as evidenced by positive FGF2, FGF9, and FGFR1 protein and/or mRNA expression. FGFR1 protein expression is correlated with FGFR1 mRNA levels and FGFR1 gene copy number. Combined analysis of FGFR1 and ligand expression may allow selection of patients with SCLC to FGFR1 inhibitor therapy.

Fibroblast Growth Factor Receptor 1 Gene Copy Number and mRNA Expression in Primary Colorectal Cancer and Its Clinicopathologic Correlation

OBJECTIVES

Fibroblast growth factor receptor 1 (FGFR1) has been reported to be overexpressed in colorectal cancer (CRC) and suggested to be a therapeutic target. In this study, we investigated FGFR1 expression and amplification in CRC and its correlation with clinicopathologic parameters.

METHODS

FGFR1 dual-color fluorescence in situ hybridization and mRNA in situ hybridization were performed on tissue array blocks composed of 291 consecutive primary CRCs.

RESULTS

Of the 291 CRC cases, FGFR1 gene amplification was found in 11 (3.8%) cases, high FGFR1 polysomy in 4 (1.4%) cases, and FGFR1 gene copy number (GCN) gain (GCN >2) in 77 (26.5%) cases. FGFR1 GCN gain was significantly associated with left-sided location, lymph node metastasis, distant metastasis, and higher TNM stage (p < 0.05). FGFR1 GCN gain also correlated with poor patient survival (p = 0.015). FGFR1 mRNA overexpression (score 3-4) was present in 11.7% (34/291) of the patients and was significantly associated with FGFR1 GCN alteration (Pearson correlation coefficient, r = 0.463; p < 0.001).

CONCLUSION

FGFR1 GCN gain was more frequently found (26.5%) than gene amplification (3.8%) and correlated with aggressive clinical behavior in consecutive CRC patients. FGFR1 GCN alteration was associated with a high FGFR1 mRNA level.

Expression profiles of HER2, EGFR, MET and FGFR2 in a large cohort of patients with gastric adenocarcinoma

BACKGROUND

Some tyrosine kinase receptors (RTKs) play critical roles in gastric cancer progression. Not only trastuzumab, but also several other agents targeting RTKs are being investigated for gastric cancer therapy. However, the simultaneous expression of multiple RTKs, which may interfere with the effectiveness of therapeutic agents, has not been evaluated in a large cohort with gastric adenocarcinoma (GAC).

METHODS

We performed a tissue microarray analysis in 950 patients with GAC who underwent a gastrectomy without preoperative chemotherapy. The protein expressions of HER2, EGFR, MET and FGFR2 were evaluated using immunohistochemistry, and the gene amplifications of HER2, EGFR and MET were examined using dual-color in situ hybridization.

RESULTS

The frequency of overexpression was 11.8% for HER2, 23.5% for EGFR, 24.9 % for MET and 31.1% for FGFR2. Whereas strong staining for each of the RTKs was heterogeneous, tumors with homogeneously strong staining areas often exhibited gene amplification. Strong EGFR expression was significantly associated with a poor outcome, but no prognostic correlations were observed in other RTKs. The overexpression of single and multiple RTKs was observed in 40.4 and 22.7% of the cases, respectively. HER2, EGFR, MET and FGFR2 predominance was observed in 10.1, 13.9, 16.1 and 22.9% of the GACs, respectively.

CONCLUSIONS

Approximately two-thirds of patients with GAC exhibited the expression of at least one RTK and would be candidates for targeted therapies. Moreover, one-third of at least one RTK overexspressing cases showed multiple RTKs expression. Our results may be useful for selecting the most suitable patients for each targeted therapy.

Redundant kinase activation and resistance of EGFR-tyrosine kinase inhibitors

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have shown dramatic effects against that tumors harboring EGFR activating mutations in the EGFR intracytoplasmic tyrosine kinase domain and resulted in cell apoptosis. Unfortunately, a number of patients ultimately developed resistance by multiple mechanisms. Thus, elucidation of the mechanism of resistance to EGFR-TKIs can provide strategies for blocking or reversing the situation. Recent studies suggested that redundant kinase activation plays pivotal roles in escaping from the effects of EGFR-TKIs. Herein, we aimed to characterize several molecular events involved in the resistance to EGFR-TKIs mediated by redundant kinase activation.

EGFR and KRAS mutations, and ALK fusions: current developments and personalized therapies for patients with advanced non-small-cell lung cancer

Personalized therapy has significantly developed in lung cancer treatment over recent years. VEGF and EGF play a major role in non-small-cell lung cancer (NSCLC) tumor angiogenesis and aggressiveness. EGFR mutation as well as KRAS and ALK rearrangements are important biomarkers in the field owing to potential targeted therapies involved in clinical practice: erlotinib, geftinib, cetuximab and crizotinib. More recently, regulation of tumor immunity through CTLA4 and PD1/L1 has emerged as a promising field in NSCLC management. This review will focus on the current and future biomarkers in the advanced NSCLC field and also address potential related targeted therapies for these patients.

[Advanced research of fibroblast growth factor receptor in non-small cell lung cancer]

Lung cancer is severely threatening human health. In recent years, the treatment for lung adenocarcinoma has made a great progress, targeted therapy has been widely applied in clinic, and benefits amount of patients. However, in squamous cell lung cancer, the incidence of epidermal growth factor receptor (EGFR) gene mutant and ALK fusion gene are low,and targeted therapy like Tarceva and crizotinib, can hardly work. Since the fibroblast growth factors (fibroblast growth factor, FGF) pathway is considered to be related to tumor cell proliferation, metastasis and angiogenesis, more and more researches proved the amplification of fibroblast growth factor receptor (FGFR) in squamous cell lung cancer. Experiments in vivo and in vitro found that blocking FGF pathway could reduce the proliferation of tumor cells and inhibit metastasis. The FGF pathway might be a new target for treatment of squamous cell lung cancer. This article reviews the effect of FGFR in tumorigenesis,as well as the prospect as a therapeutic target in non-small cell lung cancer.

Loss of Dlg-1 in the mouse lens impairs fibroblast growth factor receptor signaling

Coordination of cell proliferation, differentiation and survival is essential for normal development and maintenance of tissues in the adult organism. Growth factor receptor tyrosine kinase signaling pathways and planar cell polarity pathways are two regulators of many developmental processes. We have previously shown through analysis of mice conditionally null in the lens for the planar cell polarity gene (PCP), Dlg-1, that Dlg-1 is required for fiber differentiation. Herein, we asked if Dlg-1 is a regulator of the Fibroblast growth factor receptor (Fgfr) signaling pathway, which is known to be required for fiber cell differentiation. Western blot analysis of whole fiber cell extracts from control and Dlg-1 deficient lenses showed that levels of the Fgfr signaling intermediates pErk, pAkt, and pFrs2α, the Fgfr target, Erm, and the fiber cell specific protein, Mip26, were reduced in the Dlg-1 deficient fiber cells. The levels of Fgfr2 were decreased in Dlg-1 deficient lenses compared to controls. Conversely, levels of Fgfr1 in Dlg-1 deficient lenses were increased compared to controls. The changes in Fgfr levels were found to be specifically in the triton insoluble, cytoskeletal associated fraction of Dlg-1 deficient lenses. Immunofluorescent staining of lenses from E13.5 embryos showed that expression levels of pErk were reduced in the transition zone, a region of the lens that exhibits PCP, in the Dlg-1 deficient lenses as compared to controls. In control lenses, immunofluorescent staining for Fgfr2 was observed in the epithelium, transition zone and fibers. By E13.5, the intensity of staining for Fgfr2 was reduced in these regions of the Dlg-1 deficient lenses. Thus, loss of Dlg-1 in the lens impairs Fgfr signaling and leads to altered levels of Fgfrs, suggesting that Dlg-1 is a modulator of Fgfr signaling pathway at the level of the receptors and that Dlg-1 regulates fiber cell differentiation through its role in PCP.

Fibroblast growth factor signaling and inhibition in non-small cell lung cancer and their role in squamous cell tumors

With the introduction of targeted agents primarily applicable to non-small cell lung cancer (NSCLC) of adenocarcinoma histology, there is a heightened unmet need in the squamous cell carcinoma population. Targeting the angiogenic fibroblast growth factor (FGF)/FGF receptor (FGFR) signaling pathway is among the strategies being explored in squamous NSCLC; these efforts are supported by growth-promoting effects of FGF signaling in preclinical studies (including interactions with other pathways) and observations suggesting that FGF/FGFR-related aberrations may be more common in squamous versus adenocarcinoma and other histologies. A number of different anti-FGF/FGFR approaches have shown promise in preclinical studies. Clinical trials of two multitargeted tyrosine kinase inhibitors are restricting enrollment to patients with squamous NSCLC: a phase I/II trial of nintedanib added to first-line gemcitabine/cisplatin and a phase II trial of ponatinib for previously treated advanced disease, with the latter requiring not only squamous disease but also a confirmed FGFR kinase amplification or mutation. There are several ongoing clinical trials of multitargeted agents in general NSCLC populations, including but not limited to patients with squamous disease. Other FGF/FGFR-targeted agents are in earlier clinical development. While results are awaited from these clinical investigations in squamous NSCLC and other disease settings, additional research is needed to elucidate the role of FGF/FGFR signaling in the biology of NSCLC of different histologies.

The effects of cetuximab alone and in combination with endostatin on vascular endothelial growth factor and interleukin-8 expression in human lung adenocarcinoma cells

BACKGROUND

Angiogenesis, the growth of new blood vessels, plays an important role in tumor growth and metastasis. Both cetuximab and endostatin have been found to reduce the expression of endothelial-stimulating growth factors such as vascular endothelial growth factor (VEGF) and interleukin (IL)-8. However, the effects of cetuximab alone or in combination with endostatin on human lung adenocarcinoma cell growth remain unclear.

OBJECTIVE

The aim of this study was to evaluate the cellular and molecular effects of cetuximab alone and in combination with endostatin on human lung adenocarcinoma cell lines HI 299, SPC-A1, and H460 in vitro. Methods The epidermal growth factor receptor (EGFR) status of a panel of human lung adenocarcinoma cell lines was characterized using Western blot analysis. We used a modified tetrazolium salt assay to evaluate the growth-inhibitory effects of cetuximab and endostatin alone and in combination on the cell lines. We also determined the effects of these 2 drugs on VEGF and IL-8 expression using enzyme-linked immunosorbent assay (ELISA) and Western blot analysis. Cells were treated for 4 days with cetuximab 12.5 μ/mL, endostatin 25 μ/mL, or cetuximab 12.5 μg/mL + endostatin 25 μg/mL. Untreated cells cultured for 4 days served as controls.

RESULTS

EGFR expression in the H1299 cells was higher than in the SPC-A1 and H460 cells. Varying concentrations of cetuximab alone were associated with a significant growth-inhibitory effect on all 3 cell lines in a dose-dependent manner after 4 days of exposure compared with controls (all, P < 0.05). Compared with controls, varying concentrations of endostatin alone were not associated with significant inhibition of cell growth in any of the 3 cell lines. The inhibitory ratio of cetuximab + endostatin at varying concentrations was significantly greater than that of cetuximab alone (all, P < 0.05). On ELISA, either drug alone was associated with significant reductions in secreted VEGF and IL-8 in the HI 299, SPC-A1, and H460 cell lines (all, P < 0.05), with the exception of IL-8 concentration in the H460 cells. Mean (SD) VEGF expression with combination treatment in the H1299 and SPC-A1 cell lines (687 [21] and 629 [23] pg/mL, respectively) was significantly lower than with cetuxi-mab alone (878 [31] and 708 [20] pg/mL; both, P < 0.001); in the H460 cell line, combination treatment was not associated with a significant further reduction in VEGF expression. IL-8 concentrations with cetuximab in the H1299, SPC-A1, and H460 cell lines were 628 (20), 484 (29), and 532 (28) pg/mL, respectively, while the IL-8 concentrations with the combination treatment were 516 (20), 480 (18), and 467 (30) pg/mL. An enhanced effect of endostatin on IL-8 was observed in the H1299 and H460 cell lines (P < 0.001 and P = 0.018, respectively); however, no enhanced effect in the SPC-A1 line was observed. Similar results for VEGF and IL-8 expression were found using Western blot analysis.

CONCLUSIONS

The results from this in vitro study suggest that cetuximab treatment might both inhibit human lung adenocarcinoma cell line growth and reduce the expression of VEGF and IL-8, which are the biomarkers of angiogenesis. Endostatin was not associated with inhibition of human lung adenocarcinoma cell line growth directly. Findings with the combination of cetuximab + endostatin suggest that endostatin might enhance the antiangiogenic and antitumor activity of cetuximab through an apparent effect on VEGF expression and, to a lesser degree, on IL-8 expression.

Transcriptomic architecture of the adjacent airway field cancerization in non-small cell lung cancer

BACKGROUND

Earlier work identified specific tumor-promoting abnormalities that are shared between lung cancers and adjacent normal bronchial epithelia. We sought to characterize the yet unknown global molecular and adjacent airway field cancerization (FC) in early-stage non-small cell lung cancer (NSCLC).

METHODS

Whole-transcriptome expression profiling of resected early-stage (I-IIIA) NSCLC specimens (n = 20) with matched tumors, multiple cytologically controlled normal airways with varying distances from tumors, and uninvolved normal lung tissues (n = 194 samples) was performed using the Affymetrix Human Gene 1.0 ST platform. Mixed-effects models were used to identify differentially expressed genes among groups. Ordinal regression analysis was performed to characterize site-dependent airway expression profiles. All statistical tests were two-sided, except where noted.

RESULTS

We identified differentially expressed gene features (n = 1661) between NSCLCs and airways compared with normal lung tissues, a subset of which (n = 299), after gene set enrichment analysis, statistically significantly (P < .001) distinguished large airways in lung cancer patients from airways in cancer-free smokers. In addition, we identified genes (n = 422) statistically significantly and progressively differentially expressed in airways by distance from tumors that were found to be congruently modulated between NSCLCs and normal lung tissues. Furthermore, LAPTM4B, with statistically significantly increased expression (P < .05) in airways with shorter distance from tumors, was upregulated in human immortalized cells compared with normal bronchial epithelial cells (P < .001) and promoted anchorage-dependent and -independent lung cancer cell growth.

CONCLUSIONS

The adjacent airway FC comprises both site-independent profiles as well as gradient and localized airway expression patterns. Profiling of the airway FC may provide new insights into NSCLC oncogenesis and molecular tools for detection of the disease.

Prediction of survival in resected non-small cell lung cancer using a protein expression-based risk model: implications for personalized chemoprevention and therapy

PURPOSE

Patients with resected non-small cell lung cancer (NSCLC) are at risk for recurrence of disease, but we do not have tools to predict which patients are at highest risk. We set out to create a risk model incorporating both clinical data and biomarkers.

EXPERIMENTAL DESIGN

We assembled a comprehensive database with archival tissues and clinical follow-up from patients with NSCLC resected between 2002 and 2005. Twenty-one proteins identified from our preclinical studies as related to lung carcinogenesis were investigated, including pathways related to metabolism, DNA repair, inflammation, and growth factors. Expression of proteins was quantified using immunohistochemistry. Immunohistochemistry was chosen because it is widely available and can be performed on formalin-fixed paraffin-embedded specimens. Cox models were fitted to estimate effects of clinical factors and biomarkers on recurrence-free survival (RFS) and overall survival (OS).

RESULTS

A total of 370 patients are included in our analysis. With median follow-up of 5.3 years, median OS is 6.4 years. A total of 209 cases with recurrence or death were observed. Multicovariate risk models for RFS and OS were developed including relevant biomarkers, age, and stage. Increased expression of phospho-adenosine monophosphate-activated protein kinase (pAMPK), phospho-mTOR (pmTOR), epithelial cell adhesion molecule (EpCAM), and calcium/calmodulin-dependent serine protein kinase were significant (P < 0.05) predictors for favorable RFS; insulin receptor, chemokine (C-X-C motif) receptor 2 (CXCR2), and insulin-like growth factor-1 receptor predicted for unfavorable RFS. Significant (P < 0.05) predictors for favorable OS include pAMPK, pmTOR, and EpCAM; CXCR2 and flap structure-specific endonuclease-1 predicted unfavorable OS.

CONCLUSION

We have developed a comprehensive risk model predictive for recurrence in our large retrospective database, which is one of the largest reported series of resected NSCLC.