Increased serum levels of basic fibroblast growth factor in lung cancer patients: relevance to response of therapy and prognosis

The Design, Characterizations, and Tumor Angiogenesis Inhibition of a Multi-Epitope Peptibody With bFGF/VEGFA

Tumor angiogenesis is dependent on growth factors, and inhibition of their pathways is one of the promising strategies in cancer therapy. However, resistance to single pathway has been a great concern in clinical trials so that it necessitates multiple targetable factors for developing tumor angiogenesis inhibitors. Moreover, the strategy of Fc fusion protein is an attractive platform for novel peptide agents, which gains increasing importance with FDA approval because of better immunogenicity and stability. Here, we applied the Fc fusion protein concept to bFGF/VEGFA pathways and designed a multi-epitope Peptibody with immunogenic peptides derived from human bFGF and VEGFA sequences. Immunization with Peptibody could elicit high-titer anti-bFGF and anti-VEGFA antibodies, activate T cells, and induce Th1/Th2-type cytokines. In in vitro experiments, the isolated anti-Peptibody antibody inhibited the proliferation and migration of A549 cells and human umbilical vein endothelial cells (HUVECs) by decreasing the MAPK/Akt/mTOR signal pathways. In the murine tumor model, pre-immunization with Peptibody suppressed the tumor growth and neovascularization of lung cancer by decreasing the production of bFGF/VEGFA/PDGF, the MAPK/Akt/mTOR signal pathways, and the activation of suppressive cells in tumor sites. Further, the biological characterizations of the recombinant Peptibody were investigated systematically, including protein primary structure, secondary structure, stability, and toxicity. Collectively, the results highlighted the strategy of bFGF/VEGFA pathways and Fc fusion protein in suppressing tumor progression and angiogenesis, which emphasized the potential of multiple targetable factors for producing enduring clinical responses in tumor patients.

Cell Death, Inflammation, Tumor Burden, and Proliferation Blood Biomarkers Predict Lung Cancer Radiotherapy Response and Correlate With Tumor Volume and Proliferation Imaging

INTRODUCTION

There is an unmet need to develop noninvasive biomarkers to stratify patients in drug-radiotherapy trials. In this pilot study we investigated lung cancer radiotherapy response and toxicity blood biomarkers and correlated findings with tumor volume and proliferation imaging.

PATIENTS AND METHODS

Blood samples were collected before and during (day 21) radiotherapy. Twenty-six cell-death, hypoxia, angiogenesis, inflammation, proliferation, invasion, and tumor-burden biomarkers were evaluated. Clinical and laboratory data were collected. Univariate analysis was performed on small-cell and non-small-cell lung cancer (NSCLC) whereas multivariate analysis focused on NSCLC.

RESULTS

Blood samples from 78 patients were analyzed. Sixty-one (78.2%) harbored NSCLC, 48 (61.5%) received sequential chemoradiotherapy. Of tested baseline biomarkers, undetectable interleukin (IL)-1b (hazard ratio [HR], 4.02; 95% confidence interval [CI], 2.04-7.93; P < .001) was the only significant survival covariate. Of routinely collected laboratory tests, high baseline neutrophil count was a significant survival covariate (HR, 1.07; 95% CI, 1.02-1.11; P = .017). Baseline IL-1b and neutrophil count were prognostic for survival in a multivariate model. The addition of day-21 cytokeratin-19 antigen modestly improved this model's survival prediction (concordance probability, 0.75-0.78). Chemotherapy (P < .001) and baseline keratinocyte growth factor (P = .019) predicted acute esophagitis, but only chemotherapy remained significant after Bonferroni correction. Baseline angioprotein-1 and hepatocyte growth factor showed a direct correlation with tumor volume whereas changes in vascular cell adhesion molecule 1 showed significant correlations with 18F-fluorothymidine (FLT) positron emission tomography (PET).

CONCLUSION

Select biomarkers are prognostic after radiotherapy in this lung cancer series. The correlation between circulating biomarkers and 18F-FLT PET is shown, to our knowledge for the first time, highlighting their potential role as imaging surrogates.

The role of fibroblast growth factor 2 in patients with uterine smooth muscle tumors: an immunohistochemical study

OBJECTIVE

Fibroblast growth factor 2 (FGF-2) is considered to be a potent stimulator of angiogenesis and seems therefore to play an important role in the growth of tumors. We compared the immunohistochemical profile of FGF-2 in patients with uterine leiomyomas, smooth muscle tumors of uncertain malignant potential (STUMP) and leiomyosarcoma (LMS). Furthermore, we tried to clarify the prognostic role of FGF-2 in uterine leiomyosarcoma.

STUDY DESIGN

FGF-2 expression was investigated by immunohistochemistry from paraffin-embedded tissue in 26 patients with leiomyoma, in 24 cases with STUMP and in 21 patients with LMS. The immunohistochemical profile of these 3 tumor entities was compared and regarding LMS correlated with different clinicopathologic parameters.

RESULTS

FGF-2 was expressed in 85% of leiomyomas, in 88% of STUMP and in 57% of LMS. Significant differences regarding the frequency of FGF-2 expression were observed between leiomyoma and LMS as well as between STUMP and LMS (p<0.05). In uterine LMS FGF-2 expression was statistically more frequent in cases with high histological grade (p<0.05). Furthermore, FGF-2 positive tumors demonstrated a statistically significant higher rate of recurrence disease and tumor progression (p=0.005). Disease free as well as overall survival was significantly shortened in patients with FGF-2 positive compared to FGF-2 negative tumors (p<0.05).

CONCLUSION

The significant correlation between FGF-2 expression and high histological grade indicates that FGF-2 might work as a negative predictive factor. Higher rates of recurrence disease as well as shortened disease free and overall survival among FGF-2 positive LMS support the potential role as prognosticator for poor clinical outcome.

Targeting angiogenesis in small cell lung cancer

Small cell lung cancer (SCLC) is a highly aggressive and lethal malignancy. Despite high initial response rates to systemic chemotherapy, the disease eventually relapses; further treatment only modestly improves outcomes and overall survival (OS) for patients with extensive stage disease is less than one year. Little progress has been made during the past decades, with no new drugs approved. Consequently, the development of novel strategies is an unmet need. The inhibition of angiogenesis, a defining characteristic of cancer, has demonstrated modest efficacy in several human malignancies, including non-small cell lung cancer (NSCLC). However, results from clinical trials in SCLC have been disappointing, and no anti-angiogenic agent has received regulatory approval due to lack of clinical efficacy. The elucidation of underlying mechanisms responsible for tumor resistance to angiogenic therapy and the simultaneous blockade of multiple elements that play a role in angiogenesis need to be further explored.

Molecular and clinical significance of fibroblast growth factor 2 (FGF2 /bFGF) in malignancies of solid and hematological cancers for personalized therapies

Fibroblast growth factor (FGF) signaling is essential for normal and cancer biology. Mammalian FGF family members participate in multiple signaling pathways by binding to heparan sulfate and FGF receptors (FGFR) with varying affinities. FGF2 is the prototype member of the FGF family and interacts with its receptor to mediate receptor dimerization, phosphorylation, and activation of signaling pathways, such as Ras-MAPK and PI3K pathways. Excessive mitogenic signaling through the FGF/FGFR axis may induce carcinogenic effects by promoting cancer progression and increasing the angiogenic potential, which can lead to metastatic tumor phenotypes. Dysregulated FGF/FGFR signaling is associated with aggressive cancer phenotypes, enhanced chemotherapy resistance and poor clinical outcomes. In vitro experimental settings have indicated that extracellular FGF2 affects proliferation, drug sensitivity, and apoptosis of cancer cells. Therapeutically targeting FGF2 and FGFR has been extensively assessed in multiple preclinical studies and numerous drugs and treatment options have been tested in clinical trials. Diagnostic assays are used to quantify FGF2, FGFRs, and downstream signaling molecules to better select a target patient population for higher efficacy of cancer therapies. This review focuses on the prognostic significance of FGF2 in cancer with emphasis on therapeutic intervention strategies for solid and hematological malignancies.

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.

Clinical significance of fibroblast growth factor (FGF) expression in colorectal cancer

In this study, we serologically and pathologically examined the clinical significance of fibroblast growth factor (FGF) expression in patients with colorectal cancer. Serum basic FGF (bFGF) levels in 92 surgical colorectal cancer patients and 31 controls were measured, and the relationship between those levels and clinicopathological factors were examined. Immunohistochemical study was also conducted on specimens from 51 cancer patients, and the association between bFGF staining and serum levels were investigated. An examination of clinicopathological factors revealed significant differences in bFGF levels between stage 0-IIIb and stage IV cancers (P = 0.013). Lymphatic invasion was one factor that differed significantly. Patients with a tumor 30 mm or smaller had a bFGF level of 7.65 ± 1.11 pg/ml while patients with a tumor 31 mm or larger had a bFGF level of 8.53 ± 3.22 pg/ml; significant differences in these bFGF levels were noted (P < 0.05). Patients with a tumor that had no lymphatic invasion (ly0) had a bFGF level of 7.25 ± 0.66 pg/ml, those with a tumor that had minimal lymphatic invasion (ly1) had a bFGF level of 7.99 ± 1.68 pg/ml, and those with a tumor that had moderate lymphatic invasion (ly2) had a bFGF level of 9.17 ± 4.23 pg/ml. bFGF levels differed significantly for tumors with no/minimal lymphatic invasion (ly0-ly1) and those with moderate lymphatic invasion (ly2) (P < 0.0001). Serological examination of bFGF levels during the proliferation of colorectal cancer revealed that moderate lymphatic invasion can be readily distinguished.

Personalized Therapy of Small Cell Lung Cancer

Small cell lung cancer (SCLC) is an aggressive, poorly differentiated neuroendocrine carcinoma with distinct clinical, pathological and molecular characteristics. Despite robust responses to initial chemotherapy and radiation, the prognosis of patients with SCLC remains poor with an overall 5-year survival rate of less than 10 %. Despite the fact that numerous molecularly targeted approaches have thus far failed to demonstrate clinical utility in SCLC, further advances will rely on better definition of the biological pathways that drive survival, proliferation and metastasis. Recent next-generation, molecular profiling studies have identified many new therapeutic targets in SCLC, as well as extreme genomic instability which explains the high degree of resistance. A wide variety of anti-angiogenic agents, growth factor inhibitors, pro-apoptotic agents, and epigenetic modulators have been evaluated in SCLC and many studies of these strategies are on-going. Perhaps the most promising approaches involve agents targeting cancer stem cell pathways and immunomodulatory drugs that interfere with the PD1 and CTLA-4 pathways. SCLC offers many barriers to the development of successful therapy, including limited tumor samples, inadequate preclinical models, high mutational burden, and aggressive tumor growth which impairs functional status and hampers enrollment on clinical trials.

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.

The Fibroblast Growth Factor signaling pathway

The signaling component of the mammalian Fibroblast Growth Factor (FGF) family is comprised of eighteen secreted proteins that interact with four signaling tyrosine kinase FGF receptors (FGFRs). Interaction of FGF ligands with their signaling receptors is regulated by protein or proteoglycan cofactors and by extracellular binding proteins. Activated FGFRs phosphorylate specific tyrosine residues that mediate interaction with cytosolic adaptor proteins and the RAS-MAPK, PI3K-AKT, PLCγ, and STAT intracellular signaling pathways. Four structurally related intracellular non-signaling FGFs interact with and regulate the family of voltage gated sodium channels. Members of the FGF family function in the earliest stages of embryonic development and during organogenesis to maintain progenitor cells and mediate their growth, differentiation, survival, and patterning. FGFs also have roles in adult tissues where they mediate metabolic functions, tissue repair, and regeneration, often by reactivating developmental signaling pathways. Consistent with the presence of FGFs in almost all tissues and organs, aberrant activity of the pathway is associated with developmental defects that disrupt organogenesis, impair the response to injury, and result in metabolic disorders, and cancer. For further resources related to this article, please visit the WIREs website.

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 development of targeted therapy in small cell lung cancer

Small cell lung cancer (SCLC) is a highly aggressive cancer usually with distal metastasis and very poor prognosis. Chemotherapy is the treatment of choice for SCLC in all stages and an initial good response, but there is a high chance of disease relapse with an overall poor median survival for both stages. With increasing translational research and a better understanding of the molecular basis of cancer, a number of molecular targets have been identified in various preclinical studies. Targeted drugs have less toxicity than chemotherapy drugs, but no targeted agents have been approved for use in the treatment of SCLC patients to date. This review focuses on targeted therapies in SCLC.

Fibroblast growth factor-2 (FGF2) and syndecan-1 (SDC1) are potential biomarkers for putative circulating CD15+/CD30+ cells in poor outcome Hodgkin lymphoma patients

Background

High risk, unfavorable classical Hodgkin lymphoma (cHL) includes those patients with primary refractory or early relapse, and progressive disease. To improve the availability of biomarkers for this group of patients, we investigated both tumor biopsies and peripheral blood leukocytes (PBL) of untreated (chemo-naïve, CN) Nodular Sclerosis Classic Hodgkin Lymphoma (NS-cHL) patients for consistent biomarkers that can predict the outcome prior to frontline treatment.

Methods and materials

Bioinformatics data mining was used to generate 151 candidate biomarkers, which were screened against a library of 10 HL cell lines. Expression of FGF2 and SDC1 by CD30+ cells from HL patient samples representing good and poor outcomes were analyzed by qRT-PCR, immunohistochemical (IHC), and immunofluorescence analyses.

Results

To identify predictive HL-specific biomarkers, potential marker genes selected using bioinformatics approaches were screened against HL cell lines and HL patient samples. Fibroblast Growth Factor-2 (FGF2) and Syndecan-1 (SDC1) were overexpressed in all HL cell lines, and the overexpression was HL-specific when compared to 116 non-Hodgkin lymphoma tissues. In the analysis of stratified NS-cHL patient samples, expression of FGF2 and SDC1 were 245 fold and 91 fold higher, respectively, in the poor outcome (PO) group than in the good outcome (GO) group. The PO group exhibited higher expression of the HL marker CD30, the macrophage marker CD68, and metastatic markers TGFβ1 and MMP9 compared to the GO group. This expression signature was confirmed by qualitative immunohistochemical and immunofluorescent data. A Kaplan-Meier analysis indicated that samples in which the CD30+ cells carried an FGF2+/SDC1+ immunophenotype showed shortened survival. Analysis of chemo-naive HL blood samples suggested that in the PO group a subset of CD30+ HL cells had entered the circulation. These cells significantly overexpressed FGF2 and SDC1 compared to the GO group. The PO group showed significant down-regulation of markers for monocytes, T-cells, and B-cells. These expression signatures were eliminated in heavily pretreated patients.

Conclusion

The results suggest that small subsets of circulating CD30+/CD15+ cells expressing FGF2 and SDC1 represent biomarkers that identify NS-cHL patients who will experience a poor outcome (primary refractory and early relapsing).

Expression, prognostic and predictive impact of VEGF and bFGF in non-small cell lung cancer

Despite major advances in cancer therapeutics, the prognosis for lung cancer patients is still poor and the median survival for patients presenting with advanced non-small cell lung cancer (NSCLC) is only 8-10 months. Angiogenesis is an important biological process and a relatively early event during lung cancer pathogenesis. Anti-angiogenic agents are used in treating patients with NSCLC, and their molecular biomarkers are also being assessed to predict response. A better understanding of the biology of angiogenesis in NSCLC may reveal new targets for treating this malignancy. In this article, we review the expression and prognostic impact of the angiogenic growth factors, vascular endothelial growth factor and basic fibroblast growth factor, in NSCLC.

Prognostic impact of fibroblast growth factor 2 in non-small cell lung cancer: coexpression with VEGFR-3 and PDGF-B predicts poor survival

PURPOSE

Fibroblast growth factor 2 (FGF2; basic fibroblast growth factor, b-FGF) and its main receptor FGFR-1 are important in both hemangiogenesis and lymphangiogenesis. Murine studies have indicated a close interplay between both FGF2 and platelet-derived growth factor-B (PDGF-B) as well as FGF2 and vascular endothelial growth factor-3 (VEGFR-3). This study investigates the prognostic impact of FGF2 and FGFR-1 in tumor cells and tumor stroma of resected non-small cell lung carcinomas (NSCLC) and explores the importance of their coexpression with VEGFR-3 or PDGF-B.

METHODS

Tumor tissue samples from 335 resected patients with stage I to IIIA NSCLC were obtained and tissue microarrays were constructed from duplicate cores of tumor cells and tumor-related stroma from each specimen. Immunohistochemistry was used to evaluate the expression of the molecular markers FGF2, FGFR-1, VEGFR-3, and PDGF-B.

RESULTS

In univariate analyses, high tumor cell FGF2 expression (p = 0.015) was a negative prognostic indicator for disease-specific survival. In tumor stroma, high FGF2 (p = 0.024) expression correlated with good prognosis. In multivariate analyses, high expression of FGF2 in tumor cells (p = 0.038) was an independent negative prognostic factor whereas increased FGF2 in stroma (p = 0.015) was a positive prognosticator. Tumor cell coexpressions of FGF2/VEGFR-3 (p < 0.001) and FGFR-1/PDGF-B (p = 0.002) were significant indicators of poor prognosis.

CONCLUSIONS

Expression of FGF2 in tumor cells is an independent negative prognostic factor, and the coexpressions of FGF2/VEGFR-3 and FGFR-1/PDGF-B are strongly associated with poor survival in NSCLC patients.

Anti-angiogenic therapy using thalidomide combined with chemotherapy in small cell lung cancer: a randomized, double-blind, placebo-controlled trial

BACKGROUND

Cancer cells rely on angiogenesis for growth and dissemination, and small cell lung cancer (SCLC) is a highly angiogenic tumor. We evaluated thalidomide, an anti-angiogenic agent, when combined with chemotherapy and as maintenance treatment.

METHODS

A total of 724 patients (51% with limited and 49% with extensive disease) were randomly assigned to receive placebo or thalidomide capsules, 100-200 mg daily for up to 2 years. All patients received etoposide and carboplatin every 3 weeks for up to six cycles. Endpoints were overall survival, progression-free survival, tumor response rate, toxicity, and quality of life (QoL). Hazard ratios (HRs) for comparing thalidomide against placebo were estimated using Cox regression modeling. Statistical tests were two-sided.

RESULTS

The median overall survival was 10.5 months (placebo) and 10.1 months (thalidomide) (HR for death = 1.09, 95% confidence interval [CI] = 0.93 to 1.27; P = .28). Among patients with limited-stage disease, there was no evidence of a survival difference (HR for death = 0.91, 95% CI = 0.73 to 1.15), but among patients with extensive disease, survival was worse in the thalidomide group (HR for death = 1.36, 95% CI = 1.10 to 1.68). Progression-free survival rates were also similar in the two groups (HR = 1.07, 95% CI = 0.92 to 1.24). Thalidomide was associated with an increased risk of having a thrombotic event, mainly pulmonary embolus and deep vein thrombosis (19% thalidomide vs 10% placebo; HR = 2.13, 95% CI = 1.41 to 3.20; P < .001). There were no statistically significant differences between treatments in hematological and nonhematological toxic effects, except more patients in the thalidomide group had rash, constipation, or neuropathy. Overall, QoL scores were similar in the two treatment groups, but thalidomide was associated with less insomnia and diarrhea and more constipation and peripheral neuropathy.

CONCLUSIONS

In this large randomized trial, thalidomide in combination with chemotherapy did not improve survival of patients with SCLC but was associated with an increased risk of thrombotic events.

The fibroblast growth factor receptor signaling pathway as a mediator of intrinsic resistance to EGFR-specific tyrosine kinase inhibitors in non-small cell lung cancer

The EGFR has been targeted through the development of selective tyrosine kinase inhibitors (TKIs) that have proven effective in a subset of non-small cell lung cancer (NSCLC) patients, many bearing gain-of-function EGFR mutations or egfr gene amplification. However, the majority ( approximately 80-90%) of NSCLC patients do not respond to EGFR-specific TKIs and a high rate of acquired resistance to these therapeutics is observed in those that do respond. Thus, EGFR-specific TKIs will not, as single agents, make a high impact on overall lung cancer survival. A number of studies support the activities of other receptor tyrosine kinase pathways including cMet, IGF-1R and FGFRs as mechanisms for both intrinsic and acquired resistance to EGFR TKIs. While the role of cMet and IGF-1R signaling systems as mechanisms of resistance to EGFR TKIs has been widely reviewed in recent years, the potential role of FGFR-dependent signaling as a mechanism for EGFR TKI resistance has more recently emerged and will be highlighted herein. Due to the high degree of homology of FGFRs with VEGFRs and PDGFRs, FGFR-active TKIs already exist via development of VEGFR-targeted TKIs as angiogenesis inhibitors. Thus, these agents could be rapidly advanced into clinical investigations as FGFR inhibitors, either alone or in combination with TKIs selective for EGFR, cMet or IGF-1R as a means to expand the spectrum of NSCLC patients that can be effectively targeted with TKI-directed therapies.

Molecular and pathological signatures of epithelial-mesenchymal transitions at the cancer invasion front

Reduction of epithelial cell-cell adhesion via the transcriptional repression of cadherins in combination with the acquisition of mesenchymal properties are key determinants of epithelial-mesenchymal transition (EMT). EMT is associated with early stages of carcinogenesis, cancer invasion and recurrence. Furthermore, the tumor stroma dictates EMT through intensive bidirectional communication. The pathological analysis of EMT signatures is critically, especially to determine the presence of cancer cells at the resection margins of a tumor. When diffusion barriers disappear, EMT markers may be detected in sera from cancer patients. The detection of EMT signatures is not only important for diagnosis but can also be exploited to enhance classical chemotherapy treatments. In conclusion, further detailed understanding of the contextual cues and molecular mediators that control EMT will be required in order to develop diagnostic tools and small molecule inhibitors with potential clinical implications.

Biosensor incorporating cell barrier architectures on ion selective electrodes for early screening of cancer

Angiogenesis occurs during the early phase of cancer. Recruitment of new blood vessels by existing cancer cells leads to the release of higher concentrations of cytokines as compared to cells in healthy individuals. Some of the common cytokines observed at higher concentrations, such as vascular endothelial growth factor, basic fibroblast growth factor, hepatocyte growth factor and tumor necrosis factor-alpha, are also known to induce increased permeability across an endothelial cell monolayer. A whole-cell-based biosensor has been developed that can detect the presence of small quantities of the abovementioned cytokines individually and in different combinations. It was observed that the biosensor could differentiate between the cytokine concentrations observed in the sera of healthy individuals and cancer patients. The biosensor was also evaluated by exposing it to actual serum. These results demonstrated that the sensor can distinguish between healthy individuals and cancer patients and that the corresponding biosensor responses correlate with the stages of cancer.

Phase II trial of thalidomide with chemotherapy and as maintenance therapy for patients with poor prognosis small-cell lung cancer

BACKGROUND

Despite the high response rates achieved following standard chemotherapy for small-cell lung cancer (SCLC), the majority of patients will subsequently die from disease progression.

MATERIALS AND METHODS

We examined the efficacy and toxicity of thalidomide, an anti-angiogenic agent, in combination with carboplatin and etoposide and as maintenance therapy in patients with untreated SCLC. Twenty-five chemotherapy-naive patients with extensive disease (ED) or limited disease (LD) SCLC were enrolled in a single-arm phase II study. Carboplatin and etoposide were given every 3 weeks for 6 cycles with concurrent thalidomide 100mg orally daily. The treatment with thalidomide was continued as maintenance for up to 2 years.

RESULTS

Median progression free and overall survival were 8.3 months and 10.1 months, respectively. One-year survival was 40% and the 1-year progression-free survival was 36%. The overall response rate was 68% (95% CI 46-85%) with four complete remissions (20%) and 13 partial remissions (48%). We observed no increase in chemotherapy related toxicity. Thalidomide was well-tolerated and median time on thalidomide treatment was 7.6 months.

CONCLUSION

Concurrent thalidomide with chemotherapy followed by maintenance thalidomide appears to be well tolerated. The results on tumour response rate and survival led us to initiate a randomised phase III trial in the United Kingdom.

Enhanced expression of VEGF following bFGF inhibition in non-small cell lung cancer cell lines

Inhibition of basic fibroblast growth factor (bFGF) leads to decreased proliferation of non-small cell lung cancer (NSCLC) cell lines. Although it is well known that bFGF stimulates vascular endothelial growth factor (VEGF) secretion, the influence of bFGF-inhibition is unclear. We therefore investigated the influence of bFGF inhibition on VEGF gene expression and secretion in NSCLC cell lines. In our experiments we demonstrated that inhibition of bFGF gene and protein expression induced increased secretion of VEGF. We also observed an increase of VEGF gene expression in these cells. Furthermore, inhibition of bFGF activated the p42/p44 mitogen-activated protein kinase (MAPK). These results demonstrate that inhibition of bFGF appears to stimulate VEGF production in a p42/44 MAPK-dependent manner. These findings suggest that inhibition of bFGF alone is not a promising strategy to inhibit angiogenesis.

Pseudoscleroderma associated with cancer

In the period 1994-2002, we saw 71 patients with sclerotic skin changes; 66 were diagnosed with systemic sclerosis (SSc) while five (7%) were diagnosed with pseudoscleroderma associated with various malignancies. The mean duration of disease in these five patients was significantly shorter than that of patients with SSc. The incidence of positive antinuclear antibodies, Raynaud's phenomenon or oesophageal involvement in patients with pseudoscleroderma was significantly lower than that in patients with SSc. The distributions of skin sclerosis varied in each case. Serum basic fibroblast growth factor (bFGF) levels in the five patients with pseudoscleroderma were very elevated compared with levels in controls. Elevated expression of bFGF was detected on fibroblasts of affected skin and in one lung-cancer tissue sample obtained by excision.

Angiogenesis in non-small cell lung cancer: The prognostic impact of neoangiogenesis and the cytokines VEGF and bFGF in tumours and blood

BACKGROUND

Due to a dismal prognosis of advanced lung cancer, novel screening tools and more effective treatments are clearly needed. Lately, an increasing number of tumour-released angiogenic cytokines which affect vessel formation, tumour growth, invasion, and metastasis have been identified. Vascular endothelial growth factors (VEGFs) and basic fibroblast growth factor (bFGF) are among the most important angiogenic factors. Based on available literature, we have explored the mechanisms of angiogenesis and its prognostic significance in non-small cell lung cancer, estimated by microvessel density (MVD) and the presence of VEGF and bFGF in the tumour and blood from NSCLC patients.

METHODS

Several comprehensive Pubmed searches for the period January 1993 to May 2005 were performed using strategic combinations of the terms non-small cell lung cancer, angiogenesis, vascular endothelial growth factor, basic fibroblast growth factor, tumour expression, microvessel density, circulating, and serum.

RESULTS

NSCLC neoangiogenesis, as measured by MVD, and tumour expression of VEGF are poor prognostic factors for survival (MVD, HR 1.8-2.0; VEGF, HR 1.5). bFGF tumour expression is also associated with poor survival and more aggressive disease. When evaluating the prognostic impact of elevated VEGF levels in blood, 10 of 16 studies (63%) indicated a negative prognostic impact. Of five studies on the prognostic value of circulating bFGF, three studies reported a negative prognostic impact, while one indicated bFGF as a good prognostic factor and one was inconclusive.

CONCLUSION

Angiogenic factors are poor prognostic indicators for tumour aggressiveness and survival in NSCLC. Assessments of circulating levels of VEGF and possibly bFGF may be valuable future tools for treatment planning and monitoring of treatment effect and relapse. First, however, these blood tests need to be standardised and validated in large-scale prospective clinical trials.

Decline in angiogenic factors, such as interleukin-8, indicates response to chemotherapy of metastatic melanoma

Serum concentrations of angiogenic factors have been reported to correlate with tumour burden and prognosis in metastatic melanoma. The present study was performed to assess the value of angiogenic factors in serum in indicating response or failure to chemotherapy and immunochemotherapy in stage IV melanoma. Thirty-five patients suffering from stage IV melanoma according to the American Joint Committee on Cancer (AJCC) criteria were included in this prospective study. Before and following chemotherapy or immunochemotherapy, serum levels of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), platelet-derived growth factor (PDGF-AB), vascular cell adhesion molecule-1 (VCAM-1) and interleukin-8 (IL-8) were measured. Staging examinations following chemotherapy revealed 15 patients with response to therapy (complete response, partial response, stable disease), 14 patients with progressive disease and six patients with mixed response. Patients who responded to therapy showed a significant decrease in the serum level of IL-8 at the time of staging examinations, whereas patients with progressive disease did not. Following chemotherapy, serum concentrations of PDGF-AB had significantly decreased in both patients with response and patients with progressive disease. Comparing the VEGF and bFGF levels of responders and non-responders after a single administration of cytostatics showed significantly lower concentrations in patients with response to therapy. In all patients, a high intra- and inter-individual variability of serum values was observed during application of therapy. It can be concluded that low IL-8 serum levels after chemotherapy indicate response to chemotherapy in stage IV melanoma patients. The persistence of elevated serum levels of VEGF and bFGF following the initial cytostatic administration may help to identify patients resistant to chemotherapy. The distinct variability of serum levels indicates that processes other than tumour angiogenesis also influence the serum concentration of the examined angiogenic factors.

The role of cystatin C and the angiogenic cytokines VEGF and bFGF in patients with esophageal carcinoma

Angiogenesis is the formation of new blood vessels out of the existing vascular bed. Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) are potent circulating angiogenic factors, whereas cystatin C is one of the most important extracellular inhibitors of several cysteine proteinases. Because proteases degrade interstitial connective tissue and basement membranes during tumor growth and metastasis, an association between cystatin C and the angiogenic factors seems plausible. The primary aim of the present study was to investigate if such a correlation exists between these serum markers. The secondary aim was to determine the prognostic value of these circulating cytokines and cystatin C, collected prior to therapy, in patients with esophageal carcinoma.A total of 42 patients with esophageal carcinoma donated serum samples prior to therapy. VEGF and bFGF were correlated to platelet and leukocyte counts and VEGF was correlated to tumor volume (p = 0.04), whereas bFGF was not (p = 0.08). VEGF was significantly correlated with cystatin C (p = 0.027). Survival analysis showed that VEGF regarded as a continuous variable was associated with a significantly poorer survival in the univariate analysis (p = 0.023); however, this was not found for bFGF (p = 0.46). Neither of the angiogenic factors were associated with survival in the multivariate analysis. In the univariate analysis, cystatin c was correlated with survival (p = 0.01), but this was not found in the multivariate analysis (p = 0.28). In conclusion, VEGF was correlated with cystatin C, possible explanations being discussed in the present article. Results of the present study indicate that use of the angiogenic factors as prognostic factors, prior to therapy in patients with esophageal carcinoma, appears limited.

Circulating angiogenic cytokines in patients with advanced non-small cell lung cancer: correlation with treatment response and survival

Tumor angiogenesis is stimulated by a pro-angiogenic shift in both inducers and inhibitors of endothelial growth. To study this shift, we measured serum and plasma levels of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), endostatin, and thrombospondin 1 (TSP1) in 21 advanced non-small cell lung cancer (NSCLC) patients and 46 healthy control subjects. In addition, we assessed the relevance of these levels to disease outcome. Cytokine levels were prospectively measured in plasma and serum by enzyme-linked immunosorbent assay at three times: before chemotherapy and at 1 and 12 weeks following initiation of chemotherapy. In NSCLC patients, serum VEGF levels (sVEGF) were elevated (p<0.001), whereas serum and plasma TSP1 levels were lower (p=0.012 and p=0.004, respectively) than in healthy control subjects. Pretreatment plasma endostatin and serum bFGF levels were higher in NSCLC patients than in healthy controls (p=0.05 and 0.01, respectively). Change in sVEGF at week 12 after initiation of chemotherapy correlated with response to therapy (p=0.002). Patients with pretreatment sVEGF levels <500 pg/mL had a median survival of 11 months, but those with sVEGF >500 pg/mL had only a 6 months' median survival (p < 0.03). In NSCLC patients, VEGF levels are increased, whereas TSP1 levels are decreased, which may trigger and sustain tumor angiogenesis. High levels of serum VEGF at the time of presentation with NSCLC may predict worse survival.

Angiogenesis in non-small cell lung cancer. A new target for therapy

Non-small cell lung cancer (NSCLC) is cured with surgery in a minority of affected persons. Chemotherapy and radiation can palliate and extend survival of patients with disease not amenable to surgery. Consequently, new treatment options are urgently needed. In the era of molecularly targeted therapeutics, the recent direction in cancer research has been to identify and modulate specific events in tumorigenesis. Angiogenesis, or new vessel formation, is one such event elucidated to be fundamental to the development, growth, and metastasis of cancers and is one of the characteristics that differentiates tumor from host. Thus, targeting of tumor neovasculature continues to generate tremendous enthusiasm and effort in drug development. Extensive research into the role of angiogenesis in NSCLC has produced a host of novel targets; their potential inhibitors, now numbering over 40, are in various phases of clinical testing around the world. The current lead compounds include inhibitors of matrix metalloproteinases, angiogenic growth factors and their receptor tyrosine kinases. Despite their impressive activity in animal models, definitive evidence of their antitumor activity in humans is yet to be established. We face several challenges as we look to advance the field of antiangiogenesis for the treatment of cancer, namely, the need for a better understanding of the optimal timing and dosing of antiangiogenic agents, the validation of imaging and quantification methods of tumor angiogenesis, and a new clinical trials design for a more expedient evaluation of novel cytostatic target modulators.

Elevated fibroblast growth factor 23 in women with malignant ovarian tumors

OBJECTIVE

To determine whether fibroblast growth factor 23 (FGF23) concentrations are altered in women with ovarian cancers in which FGF physiology is known to be abnormal.

PATIENTS AND METHODS

Between May 2002 and September 2003 at the Mayo Clinic in Rochester, Minn, plasma or serum FGF23 concentrations were measured in 39 healthy women and in 14 with benign ovarian tumors, 14 with early-stage ovarian cancer, and 13 with advanced-stage ovarian cancer. Immunohistochemistry using anti-human FGF23 antibodies was performed on tissue from benign masses and advanced-stage tumors.

RESULTS

Serum or plasma FGF23 concentrations were significantly higher in women with advanced-stage ovarian cancer compared with concentrations in women with early-stage ovarian cancer or benign disease or in healthy women. A significant positive correlation was seen between serum iFGF23 and cFGF23 concentrations and stage of disease. Serum iFGF23 and cFGF23 concentrations were positively correlated with serum phosphorus among women with ovarian cancer. No patients with elevated iFGF23 or cFGF23 concentrations had hypophosphatemia. Immunohistochemistry detected FGF23 tissue staining in malignant ovarian cancer cells.

CONCLUSION

Serum or plasma FGF23 concentrations are elevated in patients with advanced-stage epithellal ovarian cancer without reductions in serum phosphate concentrations. The presence of elevated FGF23 concentrations in patients with an ovarian mass should suggest advanced-stage disease.

Influence of basic fibroblast growth factor on the proliferation of non-small cell lung cancer cell lines

Basic fibroblast growth factor (bFGF) is closely involved in angiogenesis and tumor growth of various cancers, but its role in proliferation and differentiation of non-small cell lung cancer (NSCLC) remains to be defined. The majority of NSCLC cell lines produce elevated protein levels of bFGF but do not secrete comparable amounts. We therefore investigated the influence of bFGF on the proliferation of three human NSCLC cell lines. Our experiments demonstrate that intracellular bFGF level and bFGF mRNA expression correlated with the proliferation rate in all three cell lines. Delivery of a bFGF neutralizing monoclonal antibody, anti-sense oligonucleotides or a vector expressing bFGF antisense cDNA into the cells inhibited tumor cell growth. Delivery of recombinant bFGF into a bFGF-negative cell line led to increased proliferation. These findings suggest that bFGF stimulates the growth of tumor cells by intracrine mechanisms. Strategies to inhibit bFGF in NSCLC may therefore be a promising approach in NSCLC therapy.

Serum VEGF and bFGF adds prognostic information in patients with normal platelet counts when sampled before, during and after treatment for locally advanced non-small cell lung cancer

Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) have both been implicated to have roles in tumour angiogenesis. In the present retrospective study, serum VEGF and bFGF from patients with locally advanced non-small cell lung cancer (NSCLC) were analysed before, during and after treatment. Seventy-three patients and a total of 460 serum samples were analysed for VEGF and 443 serum samples were analysed for bFGF. Pre-treatment bFGF levels in patients with normal platelet counts, were correlated to poorer survival, P-value = 0.047. During chemotherapy, each rise of one unit bFGF corresponded to a hazard ratio of 4.06 (P=0.022). In patients with normal platelet counts, VEGF levels after radiotherapy significantly correlated to good prognosis (P=0.023), during radiotherapy VEGF levels indicated the same correlation (P=0.085). We conclude that serum VEGF and especially bFGF are of clinical interest as prognostic factors, especially in patients presenting with normal platelet counts.

Evaluation of the levels of bFGF, VEGF, sICAM-1, and sVCAM-1 in serum of patients with thyroid cancer

Tumour growth and development depend on a complex cascade of angiogenic factors. The aim of the study is evaluation of the level of growth factors VEGF and bFGF, and adhesion molecules sICAM-1, sVCAM-1 in the serum of patients with papillary thyroid cancer. The study comprised 35 patients aged 21-68 years (mean age 46+/-14) who had papillary thyroid cancer diagnosed on the basis of thin needle aspiration biopsy, and were qualified for operative treatment. This group comprised 28 women and seven men. The control group was 26 healthy individuals. Serum concentrations of bFGF, VEGF, sICAM-1, and sVCAM-1 were evaluated by the enzyme-linked immunosorbent assay (ELISA) method. We have observed significantly higher mean concentrations of bFGF, VEGF, and sICAM-1 in the serum of patients with thyroid cancer compared with the control group. There was no significant difference between the sVCAM-1 concentrations of the thyroid cancer group and the control group.

Fibroblast growth factors in cancer: therapeutic possibilities

The fibroblast growth factor (FGF) family of signalling molecules and its receptors (FGFRs) contribute to normal developmental and physiological processes. However, the subversion of this powerful growth stimulatory pathway has been implicated in the generation of a variety of pathological conditions. This review focuses on the role of FGF/FGFRs in cancer. The case will be made that this signalling pathway is associated with and functionally important for the growth of some human tumours. As such, FGF/FGFRs can be viewed as rational therapeutic oncology targets and strategies used to inhibit these molecules are discussed. The therapeutic exploitation of tumour-associated FGFR expression to deliver toxins or antiproliferative signals to tumour cells is also reviewed, as is the use of FGFs as protein therapeutics to alleviate the side effects of cancer therapy.