The Winding Roadmap of Biomarkers toward Clinic: Lessons from Predictors of Resistance to Anti-EGFRs in Metastatic Colorectal Cancer.

In the evolving molecular landscape of metastatic colorectal cancer, optimizing available tools to select patients to receive anti-epidermal growth factor receptor (anti-EGFR) monoclonal antibodies is a modern challenge of colorectal oncologists. Several molecular biomarkers have been investigated in recent years as potential predictors of resistance to anti-EGFR agents in preclinical and clinical retrospective series. Nevertheless, none of them have been implemented in clinical practice due to the lack of a formal prospective demonstration. Here, we propose a literature review of molecular alterations associated with resistance to anti-EGFRs, underlining the reasons why their roadmap from laboratories to clinics was prematurely halted.

Pharmacogenomics of Targeted Agents for Personalization of Colorectal Cancer Treatment.

The use of targeted agents in the treatment of metastatic colorectal cancer (CRC) has improved patient outcomes. Anti-epidermal growth factor receptor (anti-EGFR) agents (cetuximab and panitumumab) and antiangiogenic molecules (bevacizumab, regorafeninb, ramucirumab, and aflibercept) have been successfully integrated into clinical practice. Other drugs have been designed to target additional deregulated pathways in CRC, such as MAPK (mitogen-activated protein kinase)/PI3K-AKT (phosphatidylinositol-3-kinase-AKT serine/threonine kinase)/mTOR (mammalian target of rapamycin), HER-2 and 3 ( human epidermal growth factor receptor-2 and -3), and BRAF. A major issue with targeted treatment is early identification of patients with primary or secondary drug resistance. Pharmacogenomic research has demonstrated its value in this field, highlighting some tumor mutations that could discriminate responders from non-responders. The tumor genetic profile of the RAS/RAF pathway is needed before treatment with anti-EGFR agents; mutations in EGFR pathway genes have also been explored in relation to antiangiogenic molecules although further data are required prior to their integration into clinical practice. The introduction of immunotherapy has paved the way for a new generation of predictive markers, including genome-wide assessment of the tumor landscape. Furthermore, the development of next generation sequencing technology and non-invasive approaches to analyze circulating tumor DNA will make real-time monitoring of the tumor pharmacogenomic markers possible in the clinical routine, rendering precision medicine available to every patient.

Tyrosine kinase inhibitors in breast cancer (Review).

Anti-epidermal growth factor receptor (EGFR)-targeted therapy has been intensely researched in the last years, motivated by the favorable results obtained with monoclonal antibodies in HER2-enriched breast cancer (BC) patients. Most researched alternatives of anti-EGFR agents were tyrosine kinase inhibitors (TKIs) and monoclonal antibodies. However, excluding monoclonal antibodies trastuzumab and pertuzumab, the remaining anti-EGFR molecules have exhibited disappointing results, due to the lack of specificity and frequent adverse side effects. TKIs have several advantages, including reduced cardiotoxicity, oral administration and favorable penetration of blood-brain barrier for brain metastatic BC. Lapatinib and neratinib and recently pyrotinib (approved only in China) are the only TKIs from dozens of molecules researched over the years that were approved to be used in clinical practice with limited indications, in a subset of BC patients, single or in combination with other chemotherapy or hormonal therapeutic agents. Improved identification of BC subtypes and improved characterization of aggressive forms (triple negative BC or inflammatory BC) should lead to advancements in shaping of targeted agents to improve the outcome of patients.

Adding Concurrent Chemotherapy Significantly Improves the Survival of Stage II-IVb Nasopharyngeal Carcinoma Patients Treated With Concurrent Anti-EGFR Agents.

OBJECTIVE: Anti-EGFR Targeted agents were found to be capable of modulating the antitumor immunity in head and neck cancer and become more and more frequently used in the treatment of nasopharyngeal carcinoma(NPC). We aimed to explore whether adding concurrent chemotherapy influences the survival outcome of patients with stage II-IVb NPC treated with concurrent anti-EGFR agents and intensity-modulated radiation therapy (IMRT) and explore other prognostic factors for the patients. MATERIALS AND METHODS: A total of 656 stage II-IVb NPC patients treated with concurrent anti-EGFR agents plus IMRT between January 2011 and November 2015 were enrolled. Firstly, from these patients, a well-balanced cohort of 302 patients who received concurrent chemotherapy was created by matching potential prognostic factors. Furthermore, for all 656 stage II-IVb NPC patients, univariate and multivariate analyses of overall survival (OS), progression-free survival (PFS), locoregional recurrence-free survival (LRRFS) and distant metastasis-free survival (DMFS) were conducted to identify prognostic factors and to confirm the findings from the matching cohort. RESULTS: Compared with concurrent anti-EGFR agents alone, combining concurrent cisplatin and anti-EGFR agents significantly improved the OS (5-year 94.7% versus 84.3%, P=0.012) and PFS (5-year 82.0% versus 71.7%, P=0.039) of NPC patients with more severe hematologic toxicity and mucositis. The independent prognostic factors identified by multivariate analysis of OS and PFS included concurrent chemotherapy, epstein-barr virus(EBV) status and clinical stage. Patients treated without induction chemotherapy (IC) may achieve more benefits from the addition of concurrent chemotherapy to concurrent anti-EGFR agents. CONCLUSIONS: For stage II-IVb NPC patients treated with concurrent anti-EGFR agents, the addition of concurrent chemotherapy can significantly improve the survival outcome.

Genetic Markers of the Host to Predict the Efficacy of Colorectal Cancer Targeted Therapy.

The introduction of anti-EGFR (cetuximab and panitumumab) and antiangiogenic (bevacizumab, regorafeninb, ramucirumab, and aflibercept) agents in the therapeutic armamentarium of the metastatic colorectal cancer (CRC) has significantly improved the therapeutic efficacy and patients survival. However, despite the great improvements achieved in the patients life expectation, the high inter-individual heterogeneity in the response to the targeted agents still represent an issue for the management of advanced CRC patients. Even if the role of tumor genetic mutations as predictive markers of drug efficacy has been well-established, the contribution of the host genetic markers is still controversial. Promising results regard the germ-line immune-profile, inflammation and tumor microenvironment. Inherent variations in KRAS 3'UTR region as well as EGF/ EGFR genes were investigated as markers of cetuximab effectiveness. More recently interesting data in the field of anti- EGFR agents were generated also for germ-line variants in genes involved in inflammation (e.g. COX-2, LIFR, IGF1 signaling), immune system (e.g., FCGRs, IL-1RA), and other players of the RAS signaling, including the Hippo pathway related genes (e.g. Rassf, YAP, TAZ). Host genetic variants in VEGF-dependent (i.e., EGF, IGF-1, HIF1α, eNOS, iNOS) and -independent (i.e., EMT cascade, EGFL7) pathways, with specific attention on inflammation and immune system-related factors (e.g., IL-8, CXCR-1/2, CXCR4-CXCL12 axis, TLRs, GADD34, PPP1R15A, ANXA11, MKNK1), were investigated as predictive markers of bevacizumab outcome, generating some promising results. In this review, we aimed to summarize the most recent literature data regarding the potential role of common and rare inhered variants in predicting which CRC patients will benefit more from a specifically targeted drug administration.

A Retrospective Look at Anti-EGFR Agents in Pancreatic Cancer Therapy.

BACKGROUND: The introduction of Monoclonal Antibodies (mAbs) and small-molecule Tyrosine Kinase Inhibitors (TKIs) that target the Epidermal Growth Factor Receptor (EGFR), marks a huge step forward in the Pancreatic Cancer (PC) therapy. However, anti-EGFR therapy is found to be successful only in a fraction of patients. Although anti-EGFR agents have shown considerable clinical promise, a serious adverse event associated with anti- EGFR therapy has been challenging. At this juncture, there is still more to be done in the search for effective predictive markers with therapeutic applicability. METHODS: A focused literature search was conducted to summarize the existing evidence on anti-EGFR agents in pancreatic cancer therapy. RESULTS: This review discusses various anti-EGFR agents currently in use for PC therapy and potential adverse effects associated with it. Existing evidence on EGFR TKIs demonstrated better tolerant effects and outcomes with multiple toxic regimens. Anti-EGFR therapy in combination with chemotherapy is necessary to achieve the best clinical outcomes. CONCLUSION: Future prospective studies on the identification of additional biological agents and novel anti-EGFR agents are warranted.

The role of anti-EGFR agents in patients with locoregionally advanced head and neck cancer: a meta-analysis of randomized trials.

There has been a debate over whether the addition of anti-epidermal growth factor receptor (EGFR) agents to the conventional treatments has beneficial effects in patients with head and neck squamous cell carcinoma (HNSCC). This meta-analysis was performed to investigate the role of anti-EGFR agents in patients with locoregionally advanced HNSCC (LA-HNSCC). A systematic search of the electronic databases was carried out. From eight randomized controlled trials, 2,263 patients were included in the meta-analysis. Compared with chemoradiotherapy (CRT), the addition of an EGFR inhibitor to radiotherapy (RT) or CRT did not improve locoregional control (hazard ratio (HR) = 1.19 [95% confidence interval (CI): 0.99-1.42], P = 0.06), progression-free survival (HR = 1.07 [95% CI: 0.92-1.24], P = 0.37), and overall survival (HR = 1.04 [95% CI, 0.88-1.23], P = 0.65) in patients with LA-HNSCC. Moreover, the addition of anti-EGFR agents increased the risk of skin toxicities (odds ratio = 4.04 [95% CI: 2.51-6.48], P < 0.00001) and mucositis (odds ratio = 1.58 [95% CI: 0.99-2.52], P = 0.06). In conclusion, this meta-analysis indicates that the addition of an anti-EGFR agent to RT or CRT do not improve clinical outcomes compared with CRT in patients with LA-HNSCC. Except for patients with coexisting medical conditions or decreased performance status, concurrent CRT should remain the standard of care for patients with LA-HNSCC.

Meta-analysis of the incidence and risk of arterial and venous thromboembolic events associated with anti-EGFR agents in non-small-cell lung cancer patients.

BACKGROUND: To determine the risk of arterial and venous thromboembolic events (ATEs and VETs) associated with anti-epidermal growth factor receptor (EGFR) agents in non-small-cell lung cancer (NSCLC) patients. METHODS: Prospective randomized trials evaluating therapy with or without anti-EGFR agents in NSCLC patients. Data on VTEs and ATEs were extracted. RESULTS: A total of 8,410 patients from 12 trials were included for analysis. Anti-EGFR agents significantly increased the risk of all-grade and high-grade VTEs (Peto OR 1.50, 95%CI 1.16-1.95, P = 0.002; Peto OR 1.73, 95%CI: 1.32-2.26, p < 0.001, respectively), but not for all-grade and high-grade ATEs. CONCLUSION: The use of anti-EGFR agents significantly increased the risk of all-grade and high-grade VTEs but not for ATEs in NSCLC patients.

Anti-epidermal-growth-factor-receptor agents and complete responses in the treatment of advanced non-small-cell lung cancer: a meta-analysis of 17 phase III randomized controlled trials.

PURPOSE: Currently, the anti-epidermal-growth-factor-receptor (EGFR) agents have shown encouraging treatment benefits in patients with various types of solid tumors including non-small-cell lung cancer (NSCLC). Despite these advances, radiological complete response to these therapies is rare. We meta-analyze the incidence of complete response (CR) in advanced NSCLC patients treated with anti-EGFR agents and controls in randomized controlled trials (RCTs). METHODS: PubMed, Web of Science, Embase and Cochrane library databases were reviewed for phase III RCTs with EGFR-targeted agents vs. non-EGFR-targeted agents in patients with advanced NSCLC. We calculated the odds ratio of CR in patients assigned to anti-EGFR agents compared to controls. RESULTS: A total of 11,568 patients from 17 RCTs were included for analysis. The incidence of CR in patients treated with anti-EGFR agents was 1.1% (95% CI, 0.7-1.7%) compared to 0.6% (95% CI, 0.4-0.9%) in control arms. Comparing the different types of anti-EGFR agents, the incidence of CR was 1.9% for gefitinib (95% CI: 1.4-2.6%), 1.4% for cetuximab (95% CI: 0.8-2.7%) and 0.9% for erlotinib (95% CI: 0.6-1.5%), respectively. The use of anti-EGFR agents significantly increased the odds ratio of obtaining a CR (OR 2.12, 95% CI: 1.28-3.49, p = 0.003) compared to controls. This was found to be higher in treatment arms involving more than 50% of: female patients, patients who had never smoked tobacco, patients of Asian descent or patients with adenocarcinoma or EGFR mutation. No significant differences in ORs were observed in any prespecified sub-groups. CONCLUSION: Although a CR is rare in advanced NSCLC patients receiving anti-EGFR agents, these drugs significantly increase the OR of a CR compared to controls, especially for patients with EGFR mutations. Further studies are needed to investigate whether the increase of CR with anti-EGFR therapy would be translated into survival benefits.