Fibroblast growth factor signaling in non-small-cell lung cancer

Novel molecular subtypes of METex14 non-small cell lung cancer with distinct biological and clinical significance

Not all MET exon 14 skipping (METex14) NSCLC patients benefited from MET inhibitors. We hypothesized an inter-tumoral heterogeneity in METex14 NSCLC. Investigations at genomic and transcriptomic level were conducted in METex14 NSCLC samples from stage I-III and recurrent/metastatic patients as discovery and validation cohort. Four molecular subtypes were discovered. MET-Driven subtype, with the worst prognosis, displayed MET overexpression, enrichment of MET-related pathways, and higher infiltration of fibroblast and regulatory T cells. Immune-Activated subtype having the most idea long-term survival, had higher tertiary lymphoid structures, spatial co-option of PD-L1+ cancer cells, and GZMK+ CD8+ T cell. FGFR- and Bypass-Activated subtypes displayed FGFR2 overexpression and enrichments of multiple oncogenic pathways respectively. In the validation cohort, patients with MET-Driven subtype had better response to MET inhibitors than those with MET overexpression. Thus, molecular subtypes of METex14 NSCLC with distinct biological and clinical significance may indicate more precise therapeutic strategies for METex14 NSCLC patients.

Transcriptomic profiling of reward and sensory brain areas in perinatal fentanyl exposed juvenile mice

Use of the synthetic opioid fentanyl increased ~300% in the last decade, including among women of reproductive ages. Adverse neonatal outcomes and long-term behavioral disruptions are associated with perinatal opioid exposure. Our previous work demonstrated that perinatal fentanyl exposed mice displayed enhanced negative affect and somatosensory circuit and behavioral disruptions during adolescence. However, little is known about molecular adaptations across brain regions that underlie these outcomes. We performed RNA sequencing across three reward and two sensory brain areas to study transcriptional programs in perinatal fentanyl exposed juvenile mice. Pregnant dams received 10 μg/ml fentanyl in the drinking water from embryonic day 0 (E0) through gestational periods until weaning at postnatal day 21 (P21). RNA was extracted from nucleus accumbens (NAc), prelimbic cortex (PrL), ventral tegmental area (VTA), somatosensory cortex (S1) and ventrobasal thalamus (VBT) from perinatal fentanyl exposed mice of both sexes at P35. RNA sequencing was performed, followed by analysis of differentially expressed genes (DEGs) and gene co-expression networks. Transcriptome analysis revealed DEGs and gene modules significantly associated with exposure to perinatal fentanyl in a sex-wise manner. The VTA had the most DEGs, while robust gene enrichment occurred in NAc. Genes enriched in mitochondrial respiration were pronounced in NAc and VTA of perinatal fentanyl exposed males, extracellular matrix (ECM) and neuronal migration enrichment were pronounced in NAc and VTA of perinatal fentanyl exposed males, while genes associated with vesicular cycling and synaptic signaling were markedly altered in NAc of perinatal fentanyl exposed female mice. In sensory areas from perinatal fentanyl exposed females, we found alterations in mitochondrial respiration, synaptic and ciliary organization processes. Our findings demonstrate distinct transcriptomes across reward and sensory brain regions, with some showing discordance between sexes. These transcriptome adaptations may underlie structural, functional, and behavioral changes observed in perinatal fentanyl exposed mice.

Recent Developments and Challenges in Molecular-Targeted Therapy of Non-Small-Cell Lung Cancer

Treatment of lung cancer with conventional therapies, which include radiation, surgery, and chemotherapy results in multiple undesirable adverse or side effects. The major clinical challenge in developing new drug therapies for lung cancer is resistance, which involves mutations and disturbance in various signaling pathways. Molecular abnormalities related to epidermal growth factor receptor (EGFR), v-Raf murine sarcoma viral oncogene homolog B1 (B-RAF) Kirsten rat sarcoma virus (KRAS) mutations, translocation of the anaplastic lymphoma kinase (ALK) gene, mesenchymal-epithelial transition factor (MET) amplification have been studied to overcome the resistance and to develop new therapies for non-small cell lung cancer (NSCLC). But, inevitable development of resistance presents limits the clinical benefits of various new drugs. Here, we review current progress in the development of molecularly targeted therapies, concerning six clinical biomarkers: EGFR, ALK, MET, ROS-1, KRAS, and B-RAF for NSCLC treatment.

Identifying molecular targets of Aspiletrein-derived steroidal saponins in lung cancer using network pharmacology and molecular docking-based assessments

Lung cancer is one of the leading cancers and causes of cancer-related deaths worldwide. Due to its high prevalence and mortality rate, its clinical management remains a significant challenge. Previously, the in vitro anticancer activity of Aspiletrein A, a steroid and a saponin from Aspidistra letreae, against non-small cell lung cancer (NSCLC) cells was reported. However, the anticancer molecular mechanism of other Aspiletreins from A. letreae remains unknown. Using in silico network pharmacology approaches, the targets of Aspiletreins were predicted using the Swiss Target Prediction database. In addition, key mediators in NSCLC were obtained from the Genetic databases. The compound-target interacting networks were constructed using the STRING database and Cytoscape, uncovering potential targets, including STAT3, VEGFA, HSP90AA1, FGF2, and IL2. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis demonstrated that several pathways were highly relevant to cancer pathogenesis. Additionally, molecular docking and molecular dynamic analyses revealed the interaction between key identified targets and Aspiletreins, including hydrogen bonding and Van der Waals interaction. This study provides potential targets of Aspiletreins in NSCLC, and its approach of integrating network pharmacology, bioinformatics, and molecular docking is a powerful tool for investigating the mechanism of new drug targets on a specific disease.

Epidermal growth factor receptor-Mutated Non-small-cell Lung Cancer with Intracranial Progressions and Stable Extracranial Diseases Benefit from Osimertinib Regardless of T790M Mutational Status

Objectives

Osimertinib has exhibited promising central nervous system (CNS) efficacy in Epidermal growth factor receptor (EGFR)-mutated advanced non-small-cell lung cancer (NSCLC) patients. In real-world clinical practice, patients would turn to plasma genotyping or take osimertinib blindly after CNS progression on previous tyrosine kinase inhibitors (TKIs). However, the efficacy of osimertinib in those patients according to their T790M mutational status has not been explored.

Materials and methods

Twenty-five patients who received osimertinib due to intracranial progressions with stable extracranial diseases after early-generation EGFR-TKI treatment were collected from 1032 EGFR-mutated NSCLC. Plasma samples were analyzed for EGFR mutations using next-generation sequencing (NGS) or polymerase chain reaction (PCR).

Results

Among the 25 patients, 17 patients took plasma genotyping before osimertinib treatment with 8 patients EGFR T790M mutation-positive and the rest started osimertinib blindly. The median progression-free survival (PFS) was 8.0 months (95% confidence interval [CI]: 6.12-9.94) and median intracranial PFS (iPFS) was 14.4 months (95% CI: 7.27-21.59) for the total population. No statistical difference was found in PFS and iPFS among patients with different EGFR T790M mutational statuses. Intracranial disease control rate (DCR) was 100.0% for 14 patients with evaluable intracranial lesions despite different T790M mutational statuses. DCR for extracranial lesions and overall lesions were 100.0%, 66.7%, and 87.5% for patients with T790M, no T790M, and unknown T790M mutational status, respectively.

Conclusion

For EGFR-mutated NSCLC patients with only intracranial progressions after previous TKI treatments, osimertinib is a promising treatment option regardless of T790M mutational status from plasma genotyping.

Fibroblast growth factor 11 (FGF11) promotes non-small cell lung cancer (NSCLC) progression by regulating hypoxia signaling pathway

BACKGROUND

Accumulating evidence highlights the critical roles of fibroblast growth factors (FGFs) in regulating the progression of multiple human cancers, including non-small cell lung cancer (NSCLC). In this study, we investigated the role of FGF11 in the progression of NSCLC.

METHODS

Previously published transcriptomic data (GSE75037 and GSE81089) were used to compare FGF11 expression level between NSCLC tumor tissues and adjacent normal tissues. 100 cases of NSCLC tumor tissues and 30 cases of matched adjacent normal tissues were used to validate FGF11 expression at mRNA and protein level by qPCR and immunohistochemistry. Bioinformatics analysis and dual luciferase reporter analysis were performed to confirm the regulatory effect of miR-525-5p on FGF11 expression. CCK-8 assay and transwell migration assay were employed to examine cellular proliferation, migration and invasion. Gene set enrichment analysis (GSEA) was performed to identify the signaling pathway associated with FGF11 expression. Finally, the functional role of FGF11 in NSCLC tumor growth was evaluated by in vivo study.

RESULTS

FGF11 was upregulated in NSCLC tumor tissues and tumor cell lines. High FGF11 expression was associated with a poor prognosis in NSCLC patients. In vitro loss- and gain-of function experiments demonstrated that FGF11 knockdown inhibited, whereas FGF11 overexpression promoted the proliferation, migration and invasion of NSCLC cells. Dual luciferase reporter assay confirmed that FGF11 was downregulated by miR-525-5p, and the effect of FGF11 on cell proliferation, migration and invasion could be interfered by miR-525-5p. GSEA analysis further revealed that FGF11 expression was enriched with genes in hypoxia signaling pathway and the oncogenic function of FGF11 could be suppressed by knocking down HIF-1α in NSCLC cells. Moreover, FGF11 knockdown suppressed NSCLC tumor growth whereas FGF11 overexpression promoted tumor growth in vivo.

CONCLUSIONS

Our study showed that FGF11 functions as an oncogene in tumor NSCLC progression. miR-525-5p seems to negatively regulate FGF11 and the oncogenic role of FGF11 is dependent on the upregulation of HIF-1α. Our study suggests that targeting FGF11 and HIF-1α may serve as novel strategies for the treatment of NSCLC.

An updated meta-analysis of the association between fibroblast growth factor receptor 4 polymorphisms and susceptibility to cancer

Fibroblast growth factor receptor 4 (FGFR4) is a cell surface receptor tyrosine kinases (RTKs) for FGFs.

Several studies have focused on the association between FGFR4 polymorphisms and cancer development. This meta-analysis aimed to estimate the association between FGFR4 rs351855 (Gly³⁸⁸Arg), rs1966265 (Val¹⁰Ile), rs7708357, rs2011077, and rs376618 polymorphisms and cancer risk. Eligible studies were identified from electronic databases. All statistical analyses were achieved with the STATA 14.0 software. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to quantitatively estimate the association. Overall, no significant association was found among rs351855, rs2011077, and rs376618 polymorphisms with the risk of overall cancer. The rs1966265 polymorphism significantly decreased the risk of cancer in recessive (OR = 0.87, 95% CI = 0.78–0.97, P=0.009, TT vs CT+CC) genetic model. Whereas the rs7708357 polymorphism was positively associated with cancer risk in dominant (OR = 1.17, 95% CI = 1.02–1.36, P=0.028) genetic model. Stratified analysis revealed that rs351855 variant significantly increased the risk of prostate cancer in heterozygous (OR = 1.16, 95% CI = 1.02–1.32, P=0.025 AG vs GG), dominant (OR = 1.20, 95% CI = 1.06–1.35, P=0.004, AG+AA vs GG), and allele (OR = 1.22, 95% CI = 1.06–1.41, P=0.005, A vs G) genetic models.

In summary, the findings of this meta-analysis indicate that rs1966265, rs7708357, and rs351855 polymorphisms are correlated to cancer development. Further well-designed studies are necessary to draw more precise conclusions.

Evaluation of FGFR1 as a diagnostic biomarker for ovarian cancer using TCGA and GEO datasets

Background

Malignant ovarian cancer is associated with the highest mortality of all gynecological tumors. Designing therapeutic targets that are specific to OC tissue is important for optimizing OC therapies. This study aims to identify different expression patterns of genes related to FGFR1 and the usefulness of FGFR1 as diagnostic biomarker for OC.

Methods

We collected data from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. In the TCGA cohort we analyzed clinical information according to patient characteristics, including age, stage, grade, longest dimension of the tumor and the presence of a residual tumor. GEO data served as a validation set. We obtained data on differentially expressed genes (DEGs) from the two microarray datasets. We then used gene set enrichment analysis (GSEA) to analyze the DEG data in order to identify enriched pathways related to FGFR1.

Results

Differential expression analysis revealed that FGFR1 was significantly downregulated in OC specimens. 303 patients were included in the TCGA cohort. The GEO dataset confirmed these findings using information on 75 Asian patients. The GSE105437 and GSE12470 database highlighted the significant diagnostic value of FGFR1 in identifying OC (AUC = 1, p = 0.0009 and AUC = 0.8256, p = 0.0015 respectively).

Conclusions

Our study examined existing TCGA and GEO datasets for novel factors associated with OC and identified FGFR1 as a potential diagnostic factor. Further investigation is warranted to characterize the role played by FGFR1 in OC.

Fibroblast Growth Factor-14 Acts as Tumor Suppressor in Lung Adenocarcinomas

Investigation of the molecular dynamics in lung cancer is crucial for the development of new treatment strategies. Fibroblast growth factor (FGF) 14 belongs to the FGF family, which might play a crucial role in cancer progression. We analyzed lung adenocarcinoma (LUAC) patients samples and found that FGF14 was downregulated, correlating with reduced survival and oncogenic mutation status. FGF14 overexpression in lung cancer cell lines resulted in decreased proliferation, colony formation, and migration, as well as increased expression of epithelial markers and a decreased expression of mesenchymal markers, indicating a mesenchymal to epithelial transition in vitro. We verified these findings using small interfering RNA against FGF14 and further confirmed the suppressive effect of FGF14 in a NOD.Cg-Prkdc^scid Il2rg^tm1Wjl/SzJ immunodeficient xenograft tumor model. Moreover, FGF14 overexpressing tumor cell RNA sequencing data suggests that genes affected by FGF14 were related to the extracellular matrix, playing a role in proliferation and migration. Notably, newly identified FGF14 target genes, adenosine deaminase RNA specific B1 (ADARB1), collagen and calcium-binding epidermal growth factor domain-containing protein 1 (CCBE1), α1 chain of collagen XI (COL11A1), and mucin 16 (MUC16) expression was negatively correlated with overall survival when FGF14 was downregulated in LUAC. These findings led us to suggest that FGF14 regulates proliferation and migration in LUAC.

Silencing fibroblast growth factor 7 inhibits krypton laser-induced choroidal neovascularization in a rat model

Choroidal neovascularization (CNV), a characteristic of age-related macular degeneration, is an underlying cause of severe vision loss among elderly patients. Fibroblast growth factor (FGF) is suggested to exert an important role in the pathogenesis of CNV. However, the molecular mechanisms governing this event are not fully elucidated. Herein, we identified the potential role of FGF7 in CNV. To examine the roles of FGF7 in the progression of CNV, rat CNV models were established and treated with small interfering RNA (siRNA) against FGF7 or FGF7 overexpression, followed by identification of expression of FGF7 in the CNV modeled rats. Next, proliferation and migration, and in vitro tube formation of human umbilical vein endothelial cells, as well as expression of vascular endothelial growth factor (VEGF) and transforming growth factor-beta 2 (TGF-β2) were evaluated. CNV led to upregulated FGF7 expression. Cells in the presence of FGF7 siRNA showed suppressed proliferation, migration, and tube formation, along with downregulated VEGF and TGF-β2 expression. Taken together, functional suppression of FGF7 inhibited the onset of CNV, ultimately highlighting a novel therapeutic target for suppressing CNV progression.

Honokiol induces apoptosis of lung squamous cell carcinoma by targeting FGF2-FGFR1 autocrine loop

Lung squamous cell carcinoma (SCC) accounts for a considerable proportion of lung cancer cases, but there is still a lack of effective therapies. FGFR1 amplification is generally considered a promising therapeutic target. Honokiol is a chemical compound that has been proven to be effective against various malignancies and whose analog has been reported to target the mitogen‐activated protein kinase family, members of a downstream signaling pathway of FGFR1. This was an explorative study to determine the mechanism of honokiol in lung SCC. We found that honokiol induced apoptosis and cell cycle arrest in lung SCC cell lines in a time‐ and dose‐dependent manner. Honokiol also restricted cell migration in lung SCC cell lines. Moreover, the expression of FGF2 and the activation of FGFR1 were both downregulated by honokiol. Pharmacological inhibition and siRNA knockdown of FGFR1 induced apoptosis in lung SCC cells. Our in vivo study indicated that honokiol could suppress the growth of xenograft tumors, and this effect was associated with the inhibition of the FGF2‐FGFR1 signaling pathway. In conclusion, honokiol induced cell apoptosis in lung SCC by targeting the FGF2‐FGFR1 autocrine loop.

FGFR genes mutation is an independent prognostic factor and associated with lymph node metastasis in squamous non-small cell lung cancer

Targeting FGFRs is one of the most promising therapeutic strategies in squamous non-small cell lung cancer (SQCC). However, different FGFR genomic aberrations can be associated with distinct biological characteristics that result in different clinical outcomes or therapeutic consequences. Currently, the full spectrum of FGFR gene aberrations and their clinical significance in SQCC have not been comprehensively studied. Here, we used Next-generation sequencing to investigate the presence of FGFR gene mutations in 143 tumors from patients with stage I, II or III SQCC and who had not been treated with chemotherapy or radiotherapy prior to surgery. FGFR gene mutations were identified in 24 cases, resulting in an overall frequency of 16.9%. Among the mutations, 7% (10/143) were somatic mutations, and 9.8% (14/143) germline mutations. FGFR mutations were significantly associated with an increased risk of lymph node metastasis. SQCC patients with a FGFR somatic mutation had shorter OS (overall survival, log rank P = 0.005) and DFS (disease-free survival，log rank P = 0.004) compared with those without an FGFR mutation. The multivariate analysis confirmed that a somatic mutation was an independent poor prognostic factor for OS (HR: 4.26, 95% CI: 1.49-12.16, P = 0.007) and DFS (HR: 3.16, 95% CI: 1.20-8.35, P = 0.020). Our data indicate that FGFR genes mutation is an independent prognostic factor and associated with lymph node metastasis in stage I to III Chinese SQCC patients.

A Novel Receptor Tyrosine Kinase Switch Promotes Gastrointestinal Stromal Tumor Drug Resistance

The fact that most gastrointestinal stromal tumors (GISTs) acquire resistance to imatinib (IM)-based targeted therapy remains the main driving force to identify novel molecular targets that are capable to increase GISTs sensitivity to the current therapeutic regimens. Secondary resistance to IM in GISTs typically occurs due to several mechanisms that include hemi- or homo-zygous deletion of the wild-type KIT allele, overexpression of focal adhesion kinase (FAK) and insulin-like growth factor receptor I (IGF-1R) amplification, BRAF mutation, a RTK switch (loss of c-KIT and gain of c-MET/AXL), etc. We established and characterized the IM-resistant GIST T-1 cell line (GIST T-1R) lacking secondary c-KIT mutations typical for the IM-resistant phenotype. The resistance to IM in GIST T-1R cells was due to RTK switch (loss of c-KIT/gain of FGFR2α). Indeed, we have found that FGFR inhibition reduced cellular viability, induced apoptosis and affected the growth kinetics of the IM-resistant GISTs in vitro. In contrast, IM-naive GIST T-1 parental cells were not susceptible to FGFR inhibition. Importantly, inhibition of FGF-signaling restored the susceptibility to IM in IM-resistant GISTs. Additionally, IM-resistant GISTs were less susceptible to certain chemotherapeutic agents as compared to parental IM-sensitive GIST cells. The chemoresistance in GIST T-1R cells is not due to overexpression of ABC-related transporter proteins and might be the result of upregulation of DNA damage signaling and repair (DDR) genes involved in DNA double-strand break (DSB) repair pathways (e.g., XRCC3, Rad51, etc.). Taken together, the established GIST T-1R cell subline might be used for in vitro and in vivo studies to examine the efficacy and prospective use of FGFR inhibitors for patients with IM-resistant, un-resectable and metastatic forms of GISTs with the type of RTK switch indicated above.

Genome-wide copy number variation pattern analysis and a classification signature for non-small cell lung cancer

The accurate classification of non-small cell lung carcinoma (NSCLC) into lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) is essential for both clinical practice and lung cancer research. Although the standard WHO diagnosis of NSCLC on biopsy material is rapid and economic, more than 13% of NSCLC tumors in the USA are not further classified. The purpose of this study was to analyze the genome-wide pattern differences in copy number variations (CNVs) and to develop a CNV signature as an adjunct test for the routine histopathologic classification of NSCLCs. We investigated the genome-wide CNV differences between these two tumor types using three independent patient datasets. Approximately half of the genes examined exhibited significant differences between LUAD and LUSC tumors and the corresponding non-malignant tissues. A new classifier was developed to identify signature genes out of 20 000 genes. Thirty-three genes were identified as a CNV signature of NSCLC. Using only their CNV values, the classification model separated the LUADs from the LUSCs with an accuracy of 0.88 and 0.84, respectively, in the training and validation datasets. The same signature also classified NSCLC tumors from their corresponding non-malignant samples with an accuracy of 0.96 and 0.98, respectively. We also compared the CNV patterns of NSCLC tumors with those of histologically similar tumors arising at other sites, such as the breast, head, and neck, and four additional tumors. Of greater importance, the significant differences between these tumors may offer the possibility of identifying the origin of tumors whose origin is unknown.

Efficient regulation of branching morphogenesis via fibroblast growth factor receptor 2c in early-stage embryonic mouse salivary glands

Salivary gland (SG) defects have a wide range of health implications, including xerostomia, bacterial infections, and oral health issues. Branching morphogenesis is critical for SG development. A clear understanding of the mechanisms underlying this process will accelerate SG regeneration studies. Fibroblast growth factor receptor 2 (FGFR2) interacts with multiple fibroblast growth factors (FGFs), which promote development. FGFR2 consists of two isoforms, FGFR2b and FGFR2c. FGFR2b is critical for SG development, but little is known about the expression and function of FGFR2c. We investigated the expression of all FGFR family members in fetal SGs between embryonic day 12.5 (E12.5) and E18.5. Based on RT-PCR, we observed an increase in the expression of not only Fgfr2b, but also Fgfr2c in early-stage embryonic mouse SGs, suggesting that FGFR2c is related to SG development. The branch number decreased in response to exogenous FGF2 stimulation, and this effect was suppressed by a mouse anti-FGFR2c neutralizing antibody (NA) and siRNA targeting FGFR2c, whereas FGFR2b signaling was not inhibited. Moreover, the expression of marker genes related to EMT was induced by FGF2, and this expression was suppressed by the NA. These results suggested that branching morphogenesis in SGs is regulated by FGFR2c, in addition to FGFR2b. Interestingly, FGFR2c signaling also led to increased fgf10 expression, and this increase was suppressed by the NA. FGFR2c signaling regulates branching morphogenesis through the activation of FGFR2b signaling via increased FGF10 autocrine. These results provide new insight into the mechanisms by which crosstalk between FGFR2b and FGFR2c results in efficient branching morphogenesis.

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.

Angiogenic gene therapy does not cause retinal pathology

BACKGROUND

The potential negative influence of angiogenic gene therapy on the development or progression of retinal pathologies such as diabetic retinopathy (DR) or age-related macular degeneration (AMD) has led to the systematic exclusion of affected patients from trials. We investigated the role of nonviral fibroblast factor 1 (NV1FGF) in two phase II, multinational, double-blind, randomized, placebo-controlled, gene therapy trials (TALISMAN 201 and 211).

METHODS

One hundred and fifty-two subjects with critical limb ischemia or claudication were randomized to receive eight intramuscular injections of 2.5 ml of NV1FGF at 0.2 mg/ml or 0.4 mg/dl or placebo. One hundred and fifty-two patients received a plasmid dose of NV1FGF of up to 32 mg or placebo. All patients underwent a systematic ophthalmologic examination at baseline and at 3, 6 or 12 months following gene therapy. Twenty-six of these patients (Münster subgroup) received a retinal fluorescence angiography at baseline and at final examination.

RESULTS

Among those 26 patients, four of nine patients with diabetes suffered from nonproliferative DR. Three patients showed non-exsudative AMD. No change of retinal morphology or function was observed in Münster subgroup of both TALISMAN trials independent of the intramuscular NV1FGF dosage applied.

CONCLUSIONS

Angiogenic gene therapy using NV1FGF is safe even in diabetics.

Basic fibroblast growth factor shows prognostic impact on survival in operable non-small cell lung cancer patients

Background

The important role of angiogenesis displaying in tumor development and metastasis has been generally realized. Vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and endostatin (ES) are critical members of angiogenesis modulating the balance between pro-angiogenenic and anti-angiogenenic factors. The aim of this study was to evaluate the circulating level of these factors in serum and explore their prognostic significance in 96 operable non-small cell lung cancer (NSCLC) patients.

Methods

Pre-operational serum VEGF, bFGF, and ES were determined by commercially available enzyme-link immunosorbent assay for 96 NSCLC patients and compared to a cohort of healthy controls (n = 51). Values were correlated with clinicopathological features and overall survival (OS).

Results

The pretreatment serum levels of VEGF, bFGF and ES in NSCLC were significantly higher than in the healthy control (P < 0.001, P = 0.009 and P = 0.016, respectively). Univariate survival analysis showed that a high bFGF level correlated with shorter OS and remained an independent factor in multivariate analysis (hazard ratio [HR] = 1.918, 95% confidence interval [CI], 1.061–3.464). In the squamous subtype, a high bFGF indicated a particularly poor prognosis (HR = 2.609, 95% CI, 1.188–5.729).

Conclusions

bFGF is an independent predictor of poor survival in patients with NSCLC. For patients with high serum bFGF, aggressive antitumor treatments should be given after surgery. Approaches targeting the bFGF signaling pathway should be considered as potentially promising therapeutic strategies in NSCLC, especially for the squamous subtype.

Crosstalk between KIT and FGFR3 Promotes Gastrointestinal Stromal Tumor Cell Growth and Drug Resistance

Kinase inhibitors such as imatinib have dramatically improved outcomes for patients with gastrointestinal stromal tumor (GIST), but many patients develop resistance to these treatments. Although in some patients this event corresponds with mutations in the GIST driver oncogenic kinase KIT, other patients develop resistance without KIT mutations. In this study, we address this patient subset in reporting a functional dependence of GIST on the FGF receptor FGFR3 and its crosstalk with KIT in GIST cells. Addition of the FGFR3 ligand FGF2 to GIST cells restored KIT phosphorylation during imatinib treatment, allowing sensitive cells to proliferate in the presence of the drug. FGF2 expression was increased in imatinib-resistant GIST cells, the growth of which was blocked by RNAi-mediated silencing of FGFR3. Moreover, combining KIT and FGFR3 inhibitors synergized to block the growth of imatinib-resistant cells. Signaling crosstalk between KIT and FGFR3 activated the MAPK pathway to promote resistance to imatinib. Clinically, an IHC analysis of tumor specimens from imatinib-resistant GIST patients revealed a relative increase in FGF2 levels, with a trend toward increased expression in imatinib-naïve samples consistent with possible involvement in drug resistance. Our findings provide a mechanistic rationale to evaluate existing FGFR inhibitors and multikinase inhibitors that target FGFR3 as promising strategies to improve treatment of patients with GIST with de novo or acquired resistance to imatinib.

Genomic aberrations in the FGFR pathway: opportunities for targeted therapies in solid tumors

The fibroblast growth factor receptor (FGFR) cascade plays crucial roles in tumor cell proliferation, angiogenesis, migration and survival. Accumulating evidence suggests that in some tumor types, FGFRs are bona fide oncogenes to which cancer cells are addicted. Because FGFR inhibition can reduce proliferation and induce cell death in a variety of in vitro and in vivo tumor models harboring FGFR aberrations, a growing number of research groups have selected FGFRs as targets for anticancer drug development. Multikinase FGFR/vascular endothelial growth factor receptor (VEGFR) inhibitors have shown promising activity in breast cancer patients with FGFR1 and/or FGF3 amplification. Early clinical trials with selective FGFR inhibitors, which may overcome the toxicity constraints raised by multitarget kinase inhibition, are recruiting patients with known FGFR(1-4) status based on genomic screens. Preliminary signs of antitumor activity have been demonstrated in some tumor types, including squamous cell lung carcinomas. Rational combination of targeted therapies is expected to further increase the efficacy of selective FGFR inhibitors. Herein, we discuss unsolved questions in the clinical development of these agents and suggest guidelines for management of hyperphosphatemia, a class-specific mechanism-based toxicity. In addition, we propose standardized definitions for FGFR1 and FGFR2 gene amplification based on in situ hybridization methods. Extended access to next-generation sequencing platforms will facilitate the identification of diseases in which somatic FGFR(1-4) mutations, amplifications and fusions are potentially driving cancer cell viability, further strengthening the role of FGFR signaling in cancer biology and providing more possibilities for the therapeutic application of FGFR inhibitors.

Druggable targets of squamous cell lung cancer

Knowledge of molecular pathogenesis of non-small cell lung cancer has increased remarkably and changed the principles of treatment, especially during the past decade. These advancements have been limited mainly to adenocarcinoma of the lung. Recently, genetic alterations in squamous cell lung cancer (SQCLC) have been detailed and positive results of clinical trials using agents targeting these changes have indicated the potential for improved treatment outcomes for SQCLC.

Rapid induction of lung adenocarcinoma by fibroblast growth factor 9 signaling through FGF receptor 3

Fibroblast growth factors (FGF) are expressed in many non-small cell lung carcinoma (NSCLC) primary tumors and derived cell lines, and mutations in FGF receptor 3 (FGFR3) have been identified in human lung adenocarcinoma. FGF9 has been implicated in the pathogenesis of NSCLC by synergizing with EGFR pathways or by providing an escape pathway mediating resistance to EGFR inhibition. To model pathogenic mechanisms mediated by FGF signals, we have established a mouse model in which FGF9 expression can be induced in adult lung epithelium. Here, we show that induced expression of FGF9 in adult lung leads to the rapid proliferation of distal airway epithelial cells that express the stem cell marker, Sca-1, and the proximal and distal epithelial markers, Sftpc and CC10, the rapid formation of Sftpc-positive adenocarcinomas, and eventual metastasis in some mice. Furthermore, we have identified FGFR3 as the obligate receptor mediating the FGF9 oncogenic signal. These results identify an FGF9-FGFR3 signal as a primary oncogenic pathway for lung adenocarcinoma and suggest that this pathway could be exploited for customized therapeutic applications for both primary tumors and those that have acquired resistance to inhibition of other signaling pathways.

Phase 1 study of lenvatinib combined with carboplatin and paclitaxel in patients with non-small-cell lung cancer

BACKGROUND

This dose-finding study evaluated lenvatinib, an oral multitargeted receptor tyrosine kinase inhibitor, in combination with carboplatin/paclitaxel in chemotherapy-naïve non-small-cell lung cancer (NSCLC) patients.

PATIENTS AND METHODS

Patients received lenvatinib twice daily (BID) with carboplatin (area under the curve 6 mg ml(-1) min(-1), day 1)/paclitaxel (200 mg m(-2), day 1) every 3 weeks. The initial dose of lenvatinib was 6 mg BID. The primary end point was maximum tolerated dose (MTD) of lenvatinib. At the MTD, the cohort was expanded by 16 patients. Safety, pharmacokinetics, pharmacodynamics, and antitumor effects were evaluated.

RESULTS

Twenty-eight patients were treated. At 6 mg BID, dose-limiting toxicities (DLTs) included febrile neutropenia/gingival infection (n=2). No DLTs occurred with 4 mg BID, the recommended MTD for the expansion. Common grade 3/4 toxicities included neutropenia, leukopenia, hypertension, and thrombocytopenia. The combination had no significant impact on individual drug pharmacokinetics. Response rate and median progression-free survival were 68% and 9.0 months, respectively, with 4 mg BID. In the plasma biomarker analysis, stromal cell-derived factor 1α, stem cell factor, and granulocyte colony-stimulating factor correlated with antitumor activity.

CONCLUSION

The MTD for lenvatinib with carboplatin/paclitaxel is 4 mg BID in advanced NSCLC patients. This regimen demonstrated manageable tolerability and encouraging antitumor activity.

Nonsmall cell lung cancer therapy: insight into multitargeted small-molecule growth factor receptor inhibitors

To date, lung cancer is the leading cause of cancer-related death worldwide, among which nonsmall cell lung cancer (NSCLC) comprises about 85%. Taking into account the side effects of surgery, radiation, platinum-based doublet chemotherapy, and the growth self-sufficiency characteristic of cancer cells, drugs have been discovered toward growth factor receptor (GFR) to treat NSCLC. As expected, these drugs provide a greater benefit. To increase the efficacy of such growth factor receptor tyrosine kinase inhibitors (RTKIs), coinhibition of GFR signaling pathways and combination of inhibitors along with radiation or chemotherapy have drew intense insight. Although clinical trials about single-agent RTKIs or their combination strategies suggest their increase potency against cancer, they are not beyond adverse effects, and sometimes the effects are more deadly than chemotherapy. Nevertheless the hope for RTKIs may be proved true by further researches and digging deep into cancer therapeutics.

Inhibition of lung tumorigenesis by metformin is associated with decreased plasma IGF-I and diminished receptor tyrosine kinase signaling

Metformin is the most commonly prescribed drug for type II diabetes and is associated with decreased cancer risk. Previously, we showed that metformin prevented tobacco carcinogen (NNK)-induced lung tumorigenesis in a non-diabetic mouse model, which was associated with decreased IGF-I/insulin receptor signaling but not activation of AMPK in lung tissues, as well as decreased circulating levels of IGF-I and insulin. Here, we used liver IGF-I-deficient (LID) mice to determine the importance of IGF-I in NNK-induced lung tumorigenesis and chemoprevention by metformin. LID mice had decreased lung tumor multiplicity and burden compared with wild-type (WT) mice. Metformin further decreased lung tumorigenesis in LID mice without affecting IGF-I levels, suggesting that metformin can act through IGF-I-independent mechanisms. In lung tissues, metformin decreased phosphorylation of multiple receptor tyrosine kinases (RTK) as well as levels of GTP-bound Ras independently of AMPK. Metformin also diminished plasma levels of several cognate ligands for these RTKs. Tissue distribution studies using [(14)C]-metformin showed that uptake of metformin was high in liver but four-fold lower in lungs, suggesting that the suppression of RTK activation by metformin occurs predominantly via systemic, indirect effects. Systemic inhibition of circulating growth factors and local RTK signaling are new AMPK-independent mechanisms of action of metformin that could underlie its ability to prevent tobacco carcinogen-induced lung tumorigenesis.

Genomics of squamous cell lung cancer

Approximately 30% of patients with non-small cell lung cancer have the squamous cell carcinoma (SQCC) histological subtype. Although targeted therapies have improved outcomes in patients with adenocarcinoma, no agents are currently approved specifically for use in SQCC. The Cancer Genome Atlas (TCGA) recently published the results of comprehensive genomic analyses of tumor samples from 178 patients with SQCC of the lung. In this review, we briefly discuss key molecular aberrations reported by TCGA and other investigators and their potential therapeutic implications. Carefully designed preclinical and clinical studies based on these large-scale genomic analyses are critical to improve the outcomes of patients with SQCC of lung in the near future.

Targeted agents in non-small cell lung cancer therapy: What is there on the horizon?

Lung cancer is a heterogeneous group of diseases. There has been much research in lung cancer over the past decade which has advanced our ability to treat these patients with a more personalized approach. The scope of this paper is to review the literature and give a broad understanding of the current molecular targets for which we currently have therapies as well as other targets for which we may soon have therapies. Additionally, we will cover some of the issues of resistance with these targeted therapies. The molecular targets we intend to discuss are epidermal growth factor receptor (EGFR), Vascular endothelial growth factor (VEGF), anaplastic large-cell lymphoma kinase (ALK), KRAS, C-MET/RON, PIK3CA. ROS-1, RET Fibroblast growth factor receptor (FGFR). Ephrins and their receptors, BRAF, and immunotherapies/vaccines. This manuscript only summarizes the work which has been done to date and in no way is meant to be comprehensive.

Fibroblast growth factor receptor inhibitors as a cancer treatment: from a biologic rationale to medical perspectives

The fibroblast growth factor/fibroblast growth factor receptor (FGF/FGFR) signaling pathway plays a fundamental role in many physiologic processes, including embryogenesis, adult tissue homeostasis, and wound healing, by orchestrating angiogenesis. Ligand-independent and ligand-dependent activation have been implicated in a broad range of human malignancies and promote cancer progression in tumors driven by FGF/FGFR oncogenic mutations or amplifications, tumor neoangiogenesis, and targeted treatment resistance, thereby supporting a strong rationale for anti-FGF/FGFR agent development. Efforts are being pursued to develop selective approaches for use against this pathway by optimizing the management of emerging, class-specific toxicity profiles and correctly designing clinical trials to address these different issues.

Dramatic response to inhaled dobesilate in a patient with lung squamous cell cancer

The effectiveness of local application, by inhalation, of dobesilate, an inhibitor of fibroblast growth factor signalling, in a patient with squamous cell lung carcinoma is reported. To our knowledge, these are the first published data on the efficacy of dobesilate in the treatment of this disease. The antimitotic, antiangiogenic, proapoptotic and anti-inflammatory activities of dobesilate can be important factors to consider, in explaining the efficacy of the treatment. Dobesilate administration can be a therapeutic option in patients with lung cancer having poor performance status or severe complications.

Drug resistance and its significance for treatment decisions in non-small-cell lung cancer

Non-small-cell lung cancer (nsclc) constitutes about 85% of all lung cancers. Approximately 50% of patients diagnosed with nsclc present with advanced disease (stage iii or iv) that is not amenable to curative treatment. The number of patients with stage iiib or iv disease who are alive at 1 year after diagnosis has increased from 10% in the untreated population in the early 1980s to 50% in patients with a good performance status receiving treatment today. However, those statistics remain dismal, and the two dominant reasons are the large number of patients diagnosed with advanced-stage disease and the observed primary or secondary resistance to current therapies. The present article addresses the question of drug resistance in lung cancer, focusing on subjects that are currently topical and under intense scrutiny.