Fibroblast growth factor receptor 1 amplification in non-small cell lung cancer by quantitative real-time PCR

Receptor Pharmacogenomics: Deciphering Genetic Influence on Drug Response

The paradigm "one drug fits all" or "one dose fits all" will soon be challenged by pharmacogenetics research and application. Drug response-efficacy or safety-depends on interindividual variability. The current clinical practice does not include genetic screening as a routine procedure and does not account for genetic variation. Patients with the same illness receive the same treatment, yielding different responses. Integrating pharmacogenomics in therapy would provide critical information about how a patient will respond to a certain drug. Worldwide, great efforts are being made to achieve a personalized therapy-based approach. Nevertheless, a global harmonized guideline is still needed. Plasma membrane proteins, like receptor tyrosine kinase (RTK) and G protein-coupled receptors (GPCRs), are ubiquitously expressed, being involved in a diverse array of physiopathological processes. Over 30% of drugs approved by the FDA target GPCRs, reflecting the importance of assessing the genetic variability among individuals who are treated with these drugs. Pharmacogenomics of transmembrane protein receptors is a dynamic field with profound implications for precision medicine. Understanding genetic variations in these receptors provides a framework for optimizing drug therapies, minimizing adverse reactions, and advancing the paradigm of personalized healthcare.

Combined FGFR and Akt pathway inhibition abrogates growth of FGFR1 overexpressing EGFR-TKI-resistant NSCLC cells

EGFR tyrosine kinase inhibitor (TKI) resistance in non-small cell lung cancer (NSCLC) patients is inevitable. Identification of resistance mechanisms and corresponding targeting strategies can lead to more successful later-line treatment in many patients. Using spectrometry-based proteomics, we identified increased fibroblast growth factor receptor 1 (FGFR1) expression and Akt activation across erlotinib, gefitinib, and osimertinib EGFR-TKI-resistant cell line models. We show that while combined EGFR-TKI and FGFR inhibition showed some efficacy, simultaneous inhibition of FGFR and Akt or PI3K induced superior synergistic growth inhibition of FGFR1-overexpressing EGFR-TKI-resistant NSCLC cells. This effect was confirmed in vivo. Only dual FGFR and Akt inhibition completely blocked the resistance-mediating signaling pathways downstream of Akt. Further, increased FGFR1 expression was associated with significantly lower PFS in EGFR-TKI-treated NSCLC patients, and increased FGFR1 were demonstrated in a few post- vs. pre-EGFR-TKI treatment clinical biopsies. The superior therapeutic benefit of combining FGFR and Akt inhibitors provide the rationale for clinical trials of this strategy.

The association between fibroblast growth factor receptor 1 gene amplification and lung cancer: a meta-analysis

INTRODUCTION

Identifying target oncogenic alterations in lung cancer represents a major development in disease management. We examined the association of fibroblast growth factor receptor 1 (FGFR1) gene amplification with pathological characteristics and geographic region.

MATERIAL AND METHODS

We conducted a meta-analysis of studies published between January 2010 and October 2016. Relative risks (RR) and corresponding 95% confidence intervals (CI) were calculated regarding the rate of FGFR1 amplification in different lung cancer types and geographic region.

RESULTS

Twenty-three studies (5252 patients) were included. There was heterogeneity between studies. However, in subgroup analyses for squamous cell carcinoma (SCC), small cell lung cancer (SCLC), studies using the same definition of FGFR1 amplification, and those from Australia, no significant heterogeneity was detected. The prevalence of FGFR1 amplification in these studies ranged from 4.9% to 49.2% in non-small cell lung cancer (NSCLC), 5.1% to 41.5% in SCC, 0% to 14.7% in adenocarcinoma, and 0% to 7.8% in SCLC. The prevalence of FGFR1 amplification was significantly higher in SCC than in adenocarcinoma (RR = 5.2) and SCLC (RR = 4.2). The prevalence of FGFR1 amplification ranged from 5.6% to 22.2% in Europe, 4.1% to 18.2% in the United States, 7.8% to 49.2% in Asia, and 14.2% to 18.6% in Australia. The rate of FGFR1 amplification was higher in Asians than in non-Asians (RR = 1.9) in NSCLC.

CONCLUSIONS

These results suggest that FGFR1 amplification occurs more frequently in SCC and in Asians. FGFR1 amplification may be a potential new therapeutic target for specific patients and lung cancer subtypes.

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

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

Molecular Testing of Lung Cancers

Targeted therapies guided by molecular diagnostics have become a standard treatment of lung cancer. Epidermal growth factor receptor (EGFR) mutations and anaplastic lymphoma kinase (ALK) rearrangements are currently used as the best predictive biomarkers for EGFR tyrosine kinase inhibitors and ALK inhibitors, respectively. Besides EGFR and ALK, the list of druggable genetic alterations has been growing, including ROS1 rearrangements, RET rearrangements, and MET alterations. In this situation, pathologists should carefully manage clinical samples for molecular testing and should do their best to quickly and accurately identify patients who will benefit from precision therapeutics. Here, we grouped molecular biomarkers of lung cancers into three categories—mutations, gene rearrangements, and amplifications—and propose expanded guidelines on molecular testing of lung cancers.

FGFR Signaling as a Target for Lung Cancer Therapy

Lung cancer is the leading cause of cancer-related death in developed countries. Recently, molecular targeted therapies have shown promising results in the management of lung cancer. These therapies require a clear understanding of the relevant pathways that drive carcinogenesis and maintenance of the malignant phenotype. The fibroblast growth factor receptor (FGFR) signaling axis is one such pathway that plays a central role in normal cellular function. Alterations in this pathway have been found in many cancers. In this review article, we focus on the role of this pathway in lung cancer. We present the molecular structure of FGFR, the interaction of the receptor with its ligands (the fibroblast growth factors), its downstream signaling, and aberrations in the FGFR pathway. We also discuss clinical trials involving selective and multikinase FGFR inhibitors in lung cancer treatment.

Clinicopathologic Features of Advanced Squamous NSCLC

Lung cancer remains the leading cause of cancer-related death worldwide. NSCLC accounts for more than 85% of all lung cancers, and the prognosis for advanced-stage disease is typically poor. In recent years, the importance of histologic subtypes of NSCLC has been recognized, and the distinction between squamous and other NSCLC histologic subtypes is now critical to patient management. Squamous cell lung cancer (sqCLC) represents approximately 25% to 30% of NSCLC. The prognosis for patients with advanced NSCLC is poorer for those with sqCLC than for those with adenocarcinoma. This is partly due to a number of clinical characteristics that distinguish sqCLC from other NSCLC histologic subtypes, such as smoking history, comorbid diseases, age, and molecular profile. Together, these factors make sqCLC an especially challenging disease to manage. Herein, we review some of the key clinicopathologic features of sqCLC. Understanding these features to optimally address many of the unique therapeutic challenges of this disease is likely to be central to ultimately improving outcomes for patients with squamous NSCLC.

The clinical pathological characteristics and prognosis of FGFR1 gene amplification in non-small-cell lung cancer: a meta-analysis

FGFR1 amplification is recognized as a novel therapy target for non-small-cell lung cancer (NSCLC), especially in squamous cell carcinoma (SCC). However, the association between FGFR1 amplification and the clinicopathological characteristics of NSCLC remains controversial. We performed a meta-analysis of 17 eligible studies to examine the correlation between FGFR1 gene amplification and clinicopathological characteristics. FGFR1 amplification was closely related to these clinicopathological features, including sex (odds ratio [OR] 2.05, 95% confidence interval [CI] 1.50–2.80), smoking (OR 3.31, 95% CI 2.02–5.44), and histology (OR 3.60, 95% CI 2.82–4.59). FGFR1 amplification was associated with shorter overall survival, and no significant heterogeneity existed between studies (I²=3.8%). We should note that publication bias may partly account for these results, but our findings remained significant after the trim-and-fill method (hazard ratio 1.22, 95% CI 1.06–1.40). However, no significant correlation was found with poor disease-free survival (hazard ratio 1.43, 95% CI 0.96–2.12). In conclusion, this study showed that FGFR1 amplification was significantly associated with sex, smoking, and histology. FGFR1 amplification could be a marker of poor prognosis in NSCLC patients, especially in SCC patients.

FGFR1 Amplification in Squamous Cell Carcinoma of the Lung with Correlation of Primary and Metastatic Tumor Status

BACKGROUND

The FGFR1 gene can be amplified in squamous cell carcinoma of the lung (SqCC). The aim of this study was to compare FGFR1 status with stage and matched primaries with metastases.

METHODS

Cases with FGFR1 fluorescence in situ hybridization (FISH) testing performed from 2000 to 2013 were evaluated for amplification status and clinicopathologic features.

RESULTS

Of the 336 cases tested by FGFR1 FISH, 52 (15%) were positive for amplification. Eight (13%) of 60 N0 cases and eight (17%) of 46 N1 or N2 cases were amplified, with no statistically significant difference. Of the 24 cases with matched primary and metastatic tumors, 22 (92%) were synchronous and one (4%) had discordant amplification.

CONCLUSIONS

Frequency of FGFR1 amplification is similar in SqCC with and without lymph node metastases, but status in metastatic sites may be discordant from the primary in a small subset of cases, which may affect the decision to perform testing of metastatic SqCCs.

Personalized Therapy of Non-small Cell Lung Cancer (NSCLC)

Lung cancer remains the most common cause of cancer related deaths in both men and women in the United States and non-small cell lung cancer (NSCLC) accounts for over 85 % of all lung cancers. Survival of these patients has not significantly altered in over 30 years. This chapter initially discusses the clinical presentation of lung cancer patients. Most patients diagnosed with lung cancer due to symptoms have advanced stage cancer. Once diagnosed, lung cancer patients need imaging studies to assess the stage of the disease before decisions regarding therapy are finalized. The most important prognostic factors are stage of the disease and performance status and these factors also determine therapy. The chapter subsequently discusses management of each stage of the disease and the impact of several pathologic, clinical factors in personalizing therapy for each individual patient. Transition from chemotherapy for every patient to a more personalized approach based on histology and molecular markers has occurred in the management of advanced stage NSCLC. It is expected that such a personalized approach will extend to all stages of NSCLC and will likely improve the outcomes of all NSCLC patients.

The Role of FGFR1 Gene Amplification as a Poor Prognostic Factor in Squamous Cell Lung Cancer: A Meta-Analysis of Published Data

Objectives. The prognostic factors of the fibroblast growth factor receptor 1 (FGFR1) in non-small cell lung cancer (NSCLC) remain controversial. Methods. We conducted a meta-analysis of published studies from 1974 to February 2015. In absence of quality difference between studies of reporting significant and nonsignificant results, the relationship between FGFR1 amplification and clinicopathological parameters in NSCLC was analyzed. And also the combined hazard ratio (HR) and their corresponding 95% confidence interval (CI) were calculated in terms of overall survival. Results. 3178 patients (12 studies) were included in the analysis. It was shown that FGFR1 amplification was significantly more prevalent among male patients (RR 2.03, 95% CI 1.57–2.63) with squamous cell lung cancer (SQCC) (RR 3.49, 95% CI 2.62–4.64) and current smokers (RR 2.63, 95% CI 1.92–3.60). The pooled data also showed that the FGFR1 amplification was a poor prognostic factor in SQCC (HR 1.38, 95% CI 1.07–1.78), Asian patients (HR 1.78, 95% CI 1.22–2.60), and fluorescence in situ hybridization (FISH) method (HR 1.30, 95% CI 1.06–1.58). Conclusions. This meta-analysis strongly suggests that FGFR1 amplification occurs more frequently in male, SQCC and smokers, and it is a risk factor for poor prognosis among Asian patients with SQCC.

FGFR as potential target in the treatment of squamous non small cell lung cancer

To date therapeutic options for squamous cell lung cancer patients remain scarce because no druggable targets have been identified so far. Aberrant signaling by FGFs (fibroblast growth factors) and FGFRs (fibroblast growth factors receptors) has been implicated in several human cancers and, particularly, in squamous non-small cell lung cancer (NSCLC). FGFR gene amplifications, somatic missense mutations, chromosomal translocations are the most frequent mechanisms able to induce aberrant activation of this pathway. Data from literature have established that the presence of an aberrant FGFR signaling has to be considered a possible negative prognostic factor but predictive of potential sensitivity to FGFR inhibitors. In the last years, clinical research efforts allowed to identify and evaluate promising FGFR inhibitors, such as monoclonal antibodies, ligand traps, non-selective or selective tyrosine kinase inhibitors. This review summarizes the current knowledge about FGFR alterations in NSCLC and the relative inhibitors in development, in particular in squamous NSCLC.

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

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

Oncogenic KIAA1549-BRAF fusion with activation of the MAPK/ERK pathway in pediatric oligodendrogliomas

Pediatric oligodendrogliomas (pODGs) are rare central nervous system tumors, and comparatively little is known about their molecular pathogenesis. Co-deletion of 1p/19q; and IDH1, CIC, and FUBP1 mutations, which are molecular signatures of adult oligodendrogliomas, are extremely rare in pODGs. In this report, two pODGs, one each of grade II and grade III, were evaluated using clinical, radiological, histopathologic, and follow-up methods. IDH1, TP53, CIC, H3F3A, and BRAF-V600 E mutations were analyzed by Sanger sequencing and immunohistochemical methods, and 1p/19q co-deletion was analyzed by fluorescence in situ hybridization. PDGFRA amplification, BRAF gain, intragenic duplication of FGFR-TKD, and KIAA1549-BRAF fusion (validated by Sanger sequencing) were analyzed by real-time reverse transcription PCR. Notably, both cases showed the oncogenic KIAA1549_Ex15-BRAF_Ex9 fusion transcript. Further, immunohistochemical analysis showed activation of the MAPK/ERK pathway in both of these cases. However, neither 1p/19q co-deletion; IDH1, TP53, CIC, H3F3A, nor BRAF-V600 E mutation; PDGFRA amplification; BRAF gain; nor duplication of FGFR-TKD was identified. Overall, this study highlights that pODGs can harbor the KIAA1549-BRAF fusion with aberrant MAPK/ERK signaling, and there exists an option of targeting these pathways in such patients. These results indicate that pODGs with the KIAA1549-BRAF fusion may represent a subset of this rare tumor that shares molecular and genetic features of pilocytic astrocytomas. These findings will increase our understanding of pODGs and may have clinical implications.

Fibroblast growth factor receptor 1 gene amplification is associated with poor survival in patients with resected esophageal squamous cell carcinoma

To investigate the frequency and the prognostic impact of fibroblast growth factor receptor 1 (FGFR1) gene amplification in 526 curatively resected esophageal squamous cell carcinoma (ESCC). Using fluorescent in situ hybridization, high amplification was defined by an FGFR1/centromer 8 ratio is ≥ 2.0, or average number of FGFR1 signals/tumor cell nucleus ≥ 6.0, or percentage of tumor cells containing ≥ 15 FGFR1 signals or large cluster in ≥ 10%. Low amplification was defined by ≥ 5 FGFR1 signals in ≥ 50%. FGFR2 and FGFR3 mutations were assessed by direct sequencing in 388 cases and no mutation was detected. High and low amplification were detected in 8.6% and 1.1%, respectively. High FGFR1 amplification had significantly shorter disease-free survival (34.0 vs 158.5 months P=0.019) and overall survival (52.2 vs not reached P=0.022) than low/no amplification group. After adjusting for sex, smoking, stage, histology, and adjuvant treatment, high FGFR1 amplification had a greater risk of recurrence (adjusted hazard ratio [AHR], 1.6; P=0.029) and death (AHR, 1.53; P=0.050). High amplification was significantly higher in current smokers than former and never-smokers (Ptrend<0.001) and increased proportional to smoking dosage. High FGFR1 amplification is a frequent oncogenic alteration and an independent poor prognostic factor in resected ESCC.

Molecularly targeted therapies in non-small-cell lung cancer annual update 2014

There have been significant advances in the understanding of the biology and treatment of non-small-cell lung cancer (NSCLC) during the past few years. A number of molecularly targeted agents are in the clinic or in development for patients with advanced NSCLC. We are beginning to understand the mechanisms of acquired resistance after exposure to tyrosine kinase inhibitors in patients with oncogene addicted NSCLC. The advent of next-generation sequencing has enabled to study comprehensively genomic alterations in lung cancer. Finally, early results from immune checkpoint inhibitors are very encouraging. This review summarizes recent advances in the area of cancer genomics, targeted therapies, and immunotherapy.

FGFR1 amplification in lung squamous cell carcinoma: a systematic review with meta-analysis

INTRODUCTION

Current targeted therapy proves no effective outcomes in lung squamous cell carcinoma (SQCC). Recent studies suggested that FGFR1 would be promising. This systematic review elaborated FGFR1 amplification in lung SQCC.

METHODS

An electronic search was conducted on PubMed, EMBASE, Web of SCI, Google Scholar and Cochrane Library. Eligible studies regarding incidence of FGFR1 amplification in lung SQCC and correlation between FGFR1 amplification and clinicopathological features or survival were extracted and analyzed.

RESULTS

We identified 13 eligible studies with a total of 1798 patients. The results showed about 19% of FGFR1 amplification (95% CI: 0.15-0.24; I(2)=84.5%; p=0.000). Using the same test method: FISH, definition and ethnicity, the rates were 17% (95% CI: 0.14-0.20; I(2)=53.1%; p=0.037), 21% (95% CI: 0.18-0.24; I(2)=0; p=0.615), and 16% (95% CI: 0.13-0.19; I(2)=72.1%; p=0.028), respectively. Pearson's correlation analysis suggested that smoking status was highly correlated with FGFR1 amplification (coefficient=0.961, p<0.001). FGFR1 amplification was significantly correlated with lymph node metastasis (OR: 2.27; 95% CI: 1.62-3.20; p=0.000), but not correlated with gender (OR: 1.12; 95% CI: 0.90-1.38; p=0.91), differentiation (OR: 1.02; 95% CI: 0.76-1.38; p=0.959) and stage (OR: 0.93; 95% CI: 0.73-1.19; p=0.877) in lung SQCC patients. With respect to survival, FGFR1 amplification had no influence on PFS (HR: 1.57; 95% CI: 0.85-2.30; p=0.259) and OS (HR: 1.40; 95% CI: 0.90-1.89; p=0.416) for SQCC patients.

CONCLUSION

FGFR1 amplification is about 19%. Gender, stage, differentiation, ethnicities and test methods have no influence on FGFR1 amplification. FGFR1 amplification trends to correlate with lymph node metastasis and smoking. Whether FGFR1 amplification has effect on survival remains controversial.

Oncogenic drivers, targeted therapies, and acquired resistance in non-small-cell lung cancer

In the past decade, a shift toward targeted therapies in non-small-cell lung cancer following molecular profiling has dramatically changed the way advanced adenocarcinoma is treated. However, tumor cells inevitably acquire resistance to such therapies, circumventing any sustained clinical benefit. As the genomic classification of lung cancer continues to evolve and as the mechanisms of acquired resistance to targeted therapies become elucidated and more improved target-specific drugs come into sight, the future will see more promising results from the clinic through the development of new therapeutic strategies to overcome, or prevent the development of, resistance for lung cancer patients.