A comparison of epidermal growth factor receptor levels and other prognostic parameters in non-small cell lung cancer

Aptamer-based targeted delivery systems for cancer treatment using DNA origami and DNA nanostructures

Due to the limitations of conventional cancer treatment methods, nanomedicine has appeared as a promising alternative, allowing improved drug targeting and decreased drug toxicity. In the development of cancer nanomedicines, among various nanoparticles (NPs), DNA nanostructures are more attractive because of their precisely controllable size, shape, excellent biocompatibility, programmability, biodegradability, and facile functionalization. Aptamers are introduced as single-stranded RNA or DNA molecules with recognize their corresponding targets. So, incorporating aptamers into DNA nanostructures led to influential vehicles for bioimaging and biosensing as well as targeted cancer therapy. In this review, the recent developments in the application of aptamer-based DNA origami and DNA nanostructures in advanced cancer treatment have been highlighted. Some of the main methods of cancer treatment are classified as chemo-, gene-, photodynamic- and combined therapy. Finally, the opportunities and problems for targeted DNA aptamer-based nanocarriers for medicinal applications have also been discussed.

New pyrimidine-5-carbonitrile derivatives as EGFR inhibitors with anticancer and apoptotic activity: Design, molecular modeling and synthesis

In connection with our efforts on the development of new anticancer agents, herein we report the design and synthesis of new small pyrimidine-5-carbonitrile based derivatives. The target pyrimidines were evaluated...

Targeted Therapy and Checkpoint Immunotherapy in Lung Cancer

Lung cancer is the leading cause of cancer mortality. It is classified into different histologic subtypes, including adenocarcinoma, squamous carcinoma, and large cell carcinoma (commonly referred as non-small cell lung cancer) and small cell lung cancer. Comprehensive molecular characterization of lung cancer has expanded our understanding of the cellular origins and molecular pathways affected in each of these subtypes. Many of these genetic alterations represent potential therapeutic targets for which drugs are constantly under development. This article discusses the molecular characteristics of the main lung cancer subtypes and discusses the current guidelines and novel targeted therapies, including checkpoint immunotherapy.

LncZEB1-AS1 regulates hepatocellular carcinoma bone metastasis via regulation of the miR-302b-EGFR-PI3K-AKT axis

In patients with hepatocellular carcinoma (HCC), disease progression and associated bone metastasis (BM) can markedly reduce quality of life. While the long non-coding RNA (lncRNA) zinc finger E-box binding homeobox 1 antisense 1 (ZEB1-AS1) has been shown to function as a key regulator of oncogenic processes in HCC and other tumor types, whether it plays a role in controlling HCC BM remains to be established. In the current study, we detected the significant upregulation of lncZEB1-AS1 in HCC tissues, and we found this expression to be associated with BM progression. When we knocked down this lncRNA in HCC cells, we found that this significantly reduced their migratory, invasive, and metastatic activity both in vitro and in vivo. At a mechanistic level, we found that lncZEB1-AS1 was able to target miR-302b and to thereby increase PI3K-AKT pathway activation and EGFR expression, resulting in the enhanced expression of downstream matrix metalloproteinase genes in HCC cells. In summary, our results provide novel evidence that lncZEB1-AS1 can promote HCC BM through a mechanism dependent upon the activation of PI3K-AKT signaling, thus highlighting a potentially novel therapeutic avenue for the treatment of such metastatic progression in HCC patients.

Icotinib as Adjuvant Treatment for Stage II-IIIA Lung Adenocarcinoma Patients with EGFR Mutation (ICWIP Study): Study Protocol for a Randomised Controlled Trial

The efficacy and possible role of epidermal growth factor receptor tyrosine kinase inhibitors in treating early-stage non-small-cell lung cancer have yet to be established. Therefore, we aimed to explore the efficacy and safety of icotinib in completely resected EGFR-mutant stage II-IIIA lung adenocarcinoma patients who underwent standard chemotherapy. This is a randomised, double-blinded, placebo-controlled, multicentre, Phase III trial. A total of 124 patients aged 18-75 years who qualified the inclusion criteria were recruited. These patients were randomised (1:1) to receive either icotinib (125 mg 3 times per day) or placebo (the same dosage and frequency) for 36 months, followed by a further 36 months of observational window. The primary endpoint is disease-free survival (DFS), while the secondary endpoints are overall survival, 3-year and 5-year DFS, safety and tolerability of the medication, and health-related quality-of-life. Analyses will be conducted in a full analysis set and a per-protocol set as well. To our knowledge, the present study is the first randomised, double-blinded, placebo-controlled, multicenter trial designed to explore efficacy and safety of icotonib in this population. The results obtained in the near future may provide potential guidance in clinical practice. Trial Registration: This trial was registered on www.ClinicalTrail.gov as NCT02125240.

miR-206 inhibits liver cancer stem cell expansion by regulating EGFR expression

Liver cancer stem cells (CSCs) are involved in tumorigenesis, progression, drug resistance and recurrence of hepatocellular carcinoma (HCC). However, the underlying mechanism for the propagation of liver cancer stem cells was unclear. Herein, we observed miR-206 expression was reduced in both chemoresistant HCCs and recurrent HCCs from patients. A dramatically decrease of miR-206 was detected in cluster of differentiation 133 (CD133) or epithelial cell adhesion molecule (EpCAM)-positive liver CSCs and in CSC-enriched hepatoma spheres. Functional studies revealed that a forced expression of miR-206 inhibited liver CSCs expansion by suppressing the dedifferentiation of hepatoma cells and attenuating the self-renewal of liver CSCs. Mechanistically, bioinformatic and luciferase reporter analysis identified epidermal growth factor receptor (EGFR) as a direct target of miR-206. Moreover, miR-206 downregulated the expression of EGFR in liver CSCs. There was a significant inverse correlation between miR-206 and EGFR mRNA expression in HCC samples. Special EGFR inhibitor Gefitinib abolished the discrepancy in liver CSC proportion and the self-renewal capacity between miR-206 overexpression hepatoma cells and control cells, which further confirmed that EGFR was required in miR-206-inhibited liver CSCs expansion. Conclusion: miR-206 could suppress HCC cell dedifferentiation and liver CSCs expansion by targeting EGFR signaling.

Cyclooxygenase-2 mediates gefitinib resistance in non-small cell lung cancer through the EGFR/PI3K/AKT axis

Gefitinib is a potent inhibitor of EGFR and represents the front-line treatment for non-small cell lung cancer (NSCLC) therapeutics. However, NSCLC patients are prone to develop acquired resistance through as yet, undefined mechanisms of resistance. Here, we investigated the role of COX-2 during gefitinib resistance in NSCLC cells and revealed its underlying mechanism(s) of action. We report the upregulation of COX-2 in gefitinib-resistant NSCLC tissues and cells, which is associated with poor prognosis. In vitro assays in NSCLC cells (PC9/GR) showed that COX-2 facilitates gefitinib resistance in NSCLC cells through its effects on P-gp, MRP1, and BCRP, and cancer cell migration and invasion. In vivo, COX-2 silencing could repress tumor growth. We found that the overexpression of COX-2 enhances the transcription of MMP-2, MMP-7, and MMP-9 which mediates PI3K-AKT activation. In summary, we demonstrate that COX-2 mediates the gefitinib resistance of NSCLC cells through its interaction with EGFR and the PI3K-AKT axis. This highlights COX-2 as a novel molecular target for NSCLC.

PLK1 and EGFR targeted nanoparticle as a radiation sensitizer for non-small cell lung cancer

Radiation sensitizers that can selectively act on cancer cells hold great promise to patients who receive radiation therapy. We developed a novel targeted therapy and radiation sensitizer for non-small cell lung cancer (NSCLC) based on cetuximab conjugated nanoparticle that targets epidermal growth factor receptor (EGFR) and delivers small interfering RNA (siRNA) against polo-like kinase 1 (PLK1). EGFR is overexpressed in 50% of lung cancer patients and a mediator of DNA repair, while PLK1 is a key mitotic regulator whose inhibition enhances radiation sensitivity. The nanoparticle construct (C-siPLK1-NP) effectively targets EGFR + NSCLC cells and reduces PLK1 expression, leading to G2/M arrest and cell death. Furthermore, we show a synergistic combination between C-siPLK1-NP and radiation, which was confirmed in vivo in A549 flank tumors. We also demonstrate the translational potential of C-siPLK1-NP as a systemic therapeutic in an orthotopic lung tumor model, where administration of C-siPLK1-NP reduced tumor growth and led to prolonged survival. Our findings demonstrate that C-siPLK1-NP is effective as a targeted therapy and as a potent radiation sensitizer for NSCLC. Potential application to other EGFR + cancer types such as colorectal and breast cancer is also demonstrated.

Patterns of brain metastasis in anaplastic lymphoma kinase - rearranged and epidermal growth factor receptor-mutated lung cancer patients in magnetic resonance imaging

Introduction:

The optimal management of neuroparenchymal lesions in cases of lung cancer is exigent as this frequent yet notorious complication negatively impacts the morbidity and mortality index.

Aims:

This study is aimed at recognizing various patterns of neuroparenchymal metastasis in patients of lung cancer with epidermal growth factor receptor (EGFR)- and anaplastic lymphoma kinase (ALK)-positive mutations.

Material and Methods:

The radiological findings of the neuroparenchymal lesions were analyzed and the statistical data were charted. We identified two groups of patients with neuroparenchymal lesions among a cohort of 340 patients having EGFR-positive (68) and ALK-positive (24) mutations (total: 24 + 68 = 92).

Results:

We observed that among the ALK group, leptomeningeal spread was less compared to EGFR group (2/24 as opposed to 18/68). Morphological heterogeneity and central necrosis in the parenchymal lesion which were associated with unfavorable outcomes were predominant in ALK group (8/24) as opposed to EGFR group (2/68). Ancillary findings but pertinent to survival and morbidity such as presence of perilesional edema, hemorrhage, and hydrocephalus on magnetic resonance imaging were also analyzed. The mutation-specific differential imaging spectrum could be attributed to biological differences between these cancers.

Safety Profiles and Pharmacovigilance Considerations for Recently Patented Anticancer Drugs: Lung Cancer

BACKGROUND

Lung cancer is the most frequent cause of cancer-related death. In the last decades, the introduction of targeted therapies and more recently, of immunotherapy, has led to significant improvements in different outcomes of this malignant neoplasm.

OBJECTIVE

The present review provides a balanced overview of most recent targeted therapies and immunotherapies patented for the treatment of lung cancer.

METHODS

An extensive scientific literature and patent databases search were performed to identify peerreviewed studies containing information on recently patented drugs for the treatment of lung cancer, with a particular focus on their safety data and recently patented combinations.

RESULTS

The development of therapies directed to different pathways involved in the tumor angiogenesis, proliferation, and metastasis has transformed the clinical practice of lung malignancies. Several clinical trials have shown an improvement in terms of progression-free survival and overall survival in patients with advanced/metastatic lung cancer. Safety data, extracted from clinical trials and from the WHO global database of adverse drug reactions (VigiAccessTM database), show that recently patented drugs for the treatment of lung cancer are well-tolerated and most of the adverse events reported are mild to moderate.

CONCLUSION

Currently, a consistent number of new drugs and combinations have been introduced for the treatment of patients with advanced-stage lung cancer. Safety data remain essential to better assess the long-term risk/benefit ratio of these valuable emerging therapies. The new patents' development could provide further significant improvements for lung cancer treatment.

Tropomodulin 3 modulates EGFR-PI3K-AKT signaling to drive hepatocellular carcinoma metastasis

The mechanism of hepatocellular carcinoma (HCC) metastasis remains poorly understood. Tropomodulin 3 (TMOD3) is a member of the pointed end capping protein family that contributes to invasion and metastasis in several types of malignancies. It has been found to be crucial for the membranous skeleton and embryonic development, although, its role in HCC progression remains largely unclear. We observed increased levels of Tmod3 in HCCs, especially in extrahepatic metastasis. High Tmod3 expression correlated with aggressive carcinoma and poor patient with HCC survival. Loss-of-function studies conducted by us determined Tmod3 as an oncogene that promoted HCC growth and metastasis. Mechanistically, Tmod3 increases transcription of matrix metalloproteinase-2, -7, and -9 which required PI3K-AKT. Interaction between Tmod3 and epidermal growth factor receptor (EGFR) that supports the activation of EGFR phosphorylation, is essential for signaling activation of PI3K-AKT viral oncogene homolog. These findings reveal that Tmod3 enhances aggressive behavior of HCC both in vitro and in vivo by interacting with EFGR and by activating the PI3K-AKT signaling pathway.

MiR-27a: A Novel Biomarker and Potential Therapeutic Target in Tumors

MicroRNAs (miRNAs) are endogenous, time sequencing, conserved and small non-coding RNA molecules (19-25 bp long) that regulate gene expression at the post-transcriptional level by binding to the partial sequence homology of the 3'-untranslated region of target messenger (m)RNA. The miRNA-27 family consists of miR-27a and miR-27b, which are transcribed from different chromosomes and different in nucleotide at the 3' end. It has been reported that miR-27a was located on chromosome 19 and played a vital role in tumor development. Increasing evidences support a vital role for miR-27a in modulating polymorphisms, tumorigenesis, proliferation, apoptosis, invasion, migration and angiogenesis. Apart from it, miR-27a could affect drug sensitivity, treatment of cancer and patients prognosis. The miR-27a could be an oncogene or a tumor suppressor in several types of cancer, including colon cancer, pancreatic cancer, breast cancer, bladder cancer and hepatocellular carcinoma. In this review, we discuss the role of miR-27a in tumor biology and clinical significance in detail and offer novel insights into molecular targeting therapy for human cancers.

Clinical development of targeted and immune based anti-cancer therapies

Cancer is currently the second leading cause of death globally and is expected to be responsible for approximately 9.6 million deaths in 2018. With an unprecedented understanding of the molecular pathways that drive the development and progression of human cancers, novel targeted therapies have become an exciting new development for anti-cancer medicine. These targeted therapies, also known as biologic therapies, have become a major modality of medical treatment, by acting to block the growth of cancer cells by specifically targeting molecules required for cell growth and tumorigenesis. Due to their specificity, these new therapies are expected to have better efficacy and limited adverse side effects when compared with other treatment options, including hormonal and cytotoxic therapies. In this review, we explore the clinical development, successes and challenges facing targeted anti-cancer therapies, including both small molecule inhibitors and antibody targeted therapies. Herein, we introduce targeted therapies to epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), human epidermal growth factor receptor 2 (HER2), anaplastic lymphoma kinase (ALK), BRAF, and the inhibitors of the T-cell mediated immune response, cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death protein-1 (PD-1)/ PD-1 ligand (PD-1 L).

Neurotensin promotes cholangiocarcinoma metastasis via the EGFR/AKT pathway

Cholangiocarcinoma (CCA) is a fatal disease with increasing morbidity and poor prognosis due to poor response to conventional chemotherapy or radiotherapy. Neurotensin (NTS) has long been recognized as an important factor in the central nervous system and as an endocrine agent in the peripheral circulation via NTS receptor (NTSR) mediated actions. In recent years, NTS has been implicated in the carcinogenesis of numerous cancers; however, its role in cholangiocarcinoma remains obscure. Here, we observed the expression of NTS in cholangiocarcinoma vs. non-cancerous tissues and found that up-regulation of NTS facilitated cholangiocarcinoma cell metastasis and down-regulation of NTS inhibited their migration ability. Mechanistically, NTS drove cholangiocarcinoma cell metastasis via the EGFR/AKT pathway. Both the PI3-K inhibitor LY294002 or EGFR inhibitor Erlotinib stopped the discrepant metastatic capacity between NTS-depleted cholangiocarcinoma cells and control cells, further confirming that EGFR/AKT was required in NTS-promoted cholangiocarcinoma cell metastasis. More importantly, overexpression of NTS predicted poor prognosis of CCA patients. In summary, NTS could promote cholangiocarcinoma cells metastasis by amplifying EGFR/AKT signaling and may therefore be useful to predict patient prognosis.

Epidermal growth factor receptor: Structure-function informing the design of anticancer therapeutics

Research on the epidermal growth factor (EGF) family and the family of receptors (EGFR) has progressed rapidly in recent times. New crystal structures of the ectodomains with different ligands, the activation of the kinase domain through oligomerisation and the use of fluorescence techniques have revealed profound conformational changes on ligand binding. The control of cell signaling from the EGFR-family is complex, with heterodimerisation, ligand affinity and signaling cross-talk influencing cellular outcomes. Analysis of tissue homeostasis indicates that the control of pro-ligand processing is likely to be as important as receptor activation events. Several members of the EGFR-family are overexpressed and/or mutated in cancer cells. The perturbation of EGFR-family signaling drives the malignant phenotype of many cancers and both inhibitors and antagonists of signaling from these receptors have already produced therapeutic benefits for patients. The design of affibodies, antibodies, small molecule inhibitors and even immunotherapeutic drugs targeting the EGFR-family has yielded promising new approaches to improving outcomes for cancer patients. In this review, we describe recent discoveries which have increased our understanding of the structure and dynamics of signaling from the EGFR-family, the roles of ligand processing and receptor cross-talk. We discuss the relevance of these studies to the development of strategies for designing more effective targeted treatments for cancer patients.

Long non-coding RNA THOR promotes cell proliferation and metastasis in hepatocellular carcinoma

Long non-coding RNAs (lncRNAs) have been demonstrated to be involved in the development and progression of multiple cancers by previous studies. Recently, a novel lncRNA, THOR (testis-associated highly conserved oncogenic long non-coding RNA), was characterized in human cancers and shown to exhibit an oncogenic role. However, the role of THOR in hepatocellular carcinoma (HCC) is still unclear. In this study, we found that THOR was relatively highly expressed in human HCC tissues and cell lines. Notably, high THOR expression was associated with worse prognosis. THOR depletion resulted in significant inhibition of the growth and metastasis of HCC cells. Mechanistically, THOR drives HCC cell progression via the PTEN/AKT pathway. Moreover, the specific PI3-K inhibitor LY294002 abolished the discrepancy in the growth and metastatic capacity between THOR-silenced HCC cells and control cells, which further confirmed that AKT was required in THOR-driven HCC cell growth and metastasis. Taken together, our results suggest that THOR could promote HCC cell growth and metastasis by amplifying PTEN/AKT signaling and may be a new therapeutic target and predictive factor for HCC.

Selection of Luteolin as a potential antagonist from molecular docking analysis of EGFR mutant

The life-threatening sides effect of the current EGFR mutant inhibitors (drugs) such as the eruption of rash which can be seen on the face, chest, back and even the trunk, diarrhea, nausea, vomiting, anorexia and stomatitis, necessitates the discovery of new potent and safe compounds as a chemo-therapeutic measure against lung cancer. Approximately about 10% of patients with Non-small cell lung cancer (NSCLC) in the US and about 35% in East Asia have tumor associated EGFR. These mutations occur within EGFR exon 18-21, which encodes a portion of the EGFR kinase domain and enables researchers to identify compounds that only recognizes and binds to the cancer cells. Thus, mutations in EGFR play a role as both biomarkers and rational targets for targeted therapy. In view of this, we out-source for the best-in -class inhibitor for this druggable target via computational tools. The purpose of this study was to analyze the inhibitory potential of luteolin by computational docking studies. For this, three (3) flavone chemical compounds (phytochemicals) retrieved from literatures were screened for their inhibitory effects on the epidermal growth factor receptor (EGFR). Luteolin was the lead compound with a binding energy of -7.7 kcal/mol. Computational docking analysis was performed using PyRx, AutoDock Vina option based on scoring functions and the target was validated so as to ensure that the right target and appropriate docking protocol was used for this analysis.

A randomized, phase II study of gefitinib alone versus nimotuzumab plus gefitinib after platinum-based chemotherapy in advanced non-small cell lung cancer (KCSG LU12-01)

We aimed to evaluate the efficacy of dual inhibition of epidermal growth factor receptor (EGFR) with nimotuzumab (EGFR monoclonal antibody) plus gefitinib (EGFR-tyrosine kinase inhibitor) in advanced non-small cell lung cancer (NSCLC) after platinum-based chemotherapy. An open label, randomized, phase II trial was conducted at 6 centers; 160 patients were randomized (1:1) to either gefitinib alone or nimotuzumab (200 mg, i.v. weekly) plus gefitinib (250 mg p.o. daily) until disease progression or intolerable toxicity. The primary endpoint was progression-free survival (PFS) at 3 months. Of the total 160 enrolled patients, 155 (77: gefitinib, 78: nimotuzumab plus gefitinib) received at least one dose and could be evaluated for efficacy and toxicity. The majority had adenocarcinoma (65.2%) and ECOG performance status of 0 to 1 (83.5%). The median follow-up was 22.1 months, and the PFS rate at 3 months was 48.1% in gefitinib and 37.2% in nimotuzumab plus gefitinib (P = not significant, NS). The median PFS and OS were 2.8 and 13.2 months in gefitinib and 2.0 and 14.0 months in nimotuzumab plus gefitinib. Combined treatment was not associated with superior PFS to gefitinib alone in patients with EGFR mutation (13.5 vs. 10.2 months in gefitinib alone, P=NS) or those with wild-type EGFR (0.9 vs. 2.0 months in gefitinib alone, P=NS). Combined treatment did not increase EGFR inhibition-related adverse events with manageable toxicities. The dual inhibition of EGFR with nimotuzumab plus gefitinib was not associated with better outcomes than gefitinib alone as a second-line treatment of advanced NSCLC (NCT01498562).

Patterns of spread and prognostic implications of lung cancer metastasis in an era of driver mutations

BACKGROUND

In the present study, we examined the pattern of metastatic spread in patients with advanced non-small-cell lung cancer (nsclc) and the effect of EGFR mutations.

METHODS

Patients were identified from a provincial cancer registry, and individual medical records were reviewed. Patients were included if they had stage iv nsclc and underwent diagnostic EGFR mutation testing. Patients were divided into EGFR mutation-positive (EGFR+) and EGFR wild type (wt) cohorts. The primary endpoint was the cumulative incidence for each metastatic site: lung, bone, brain, liver, adrenal glands, distant nodes, and other. Cumulative incidence curves were estimated using a competing-risks method. The secondary outcome was survival.

RESULTS

Of the 543 identified patients, 121 (22.3%) tested as EGFR+, and 422 (77.7%) tested as EGFR wt. The incidence of brain (39.2% vs. 28.2%, p = 0.038) and lung (61.2% vs. 51.0%, p = 0.048) metastasis was higher in the EGFR+ cohort than in the EGFR wt cohort. In the EGFR+ cohort, a higher incidence of liver metastasis was associated with the exon 21 mutation subtype than with the exon 19 deletion subtype [23% vs. 7%, p < 0.01; hazard ratio (hr): 3.47]. Median survival was significantly longer for the EGFR+ cohort than for the EGFR wt cohort (22.4 months vs. 7.9 months, p < 0.001). In multivariable analysis, brain (hr: 1.73), liver (hr: 1.69), and bone (hr: 1.89) metastases were associated with worse survival.

CONCLUSIONS

Rates of lung and brain metastases are higher in EGFR mutation carriers, even when adjusted for differences in survival. Brain, liver, and bone metastases are independent negative prognostic factors for survival.

Epidermal Growth Factor Receptor Cell Proliferation Signaling Pathways

The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase that is commonly upregulated in cancers such as in non-small-cell lung cancer, metastatic colorectal cancer, glioblastoma, head and neck cancer, pancreatic cancer, and breast cancer. Various mechanisms mediate the upregulation of EGFR activity, including common mutations and truncations to its extracellular domain, such as in the EGFRvIII truncations, as well as to its kinase domain, such as the L858R and T790M mutations, or the exon 19 truncation. These EGFR aberrations over-activate downstream pro-oncogenic signaling pathways, including the RAS-RAF-MEK-ERK MAPK and AKT-PI3K-mTOR pathways. These pathways then activate many biological outputs that are beneficial to cancer cell proliferation, including their chronic initiation and progression through the cell cycle. Here, we review the molecular mechanisms that regulate EGFR signal transduction, including the EGFR structure and its mutations, ligand binding and EGFR dimerization, as well as the signaling pathways that lead to G1 cell cycle progression. We focus on the induction of CYCLIN D expression, CDK4/6 activation, and the repression of cyclin-dependent kinase inhibitor proteins (CDKi) by EGFR signaling pathways. We also discuss the successes and challenges of EGFR-targeted therapies, and the potential for their use in combination with CDK4/6 inhibitors.

Epidermal Growth Factor Receptor Cell Proliferation Signaling Pathways

The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase that is commonly upregulated in cancers such as in non-small-cell lung cancer, metastatic colorectal cancer, glioblastoma, head and neck cancer, pancreatic cancer, and breast cancer. Various mechanisms mediate the upregulation of EGFR activity, including common mutations and truncations to its extracellular domain, such as in the EGFRvIII truncations, as well as to its kinase domain, such as the L858R and T790M mutations, or the exon 19 truncation. These EGFR aberrations over-activate downstream pro-oncogenic signaling pathways, including the RAS-RAF-MEK-ERK MAPK and AKT-PI3K-mTOR pathways. These pathways then activate many biological outputs that are beneficial to cancer cell proliferation, including their chronic initiation and progression through the cell cycle. Here, we review the molecular mechanisms that regulate EGFR signal transduction, including the EGFR structure and its mutations, ligand binding and EGFR dimerization, as well as the signaling pathways that lead to G1 cell cycle progression. We focus on the induction of CYCLIN D expression, CDK4/6 activation, and the repression of cyclin-dependent kinase inhibitor proteins (CDKi) by EGFR signaling pathways. We also discuss the successes and challenges of EGFR-targeted therapies, and the potential for their use in combination with CDK4/6 inhibitors.

Phase 1 study of romidepsin plus erlotinib in advanced non-small cell lung cancer

PURPOSE

Preclinical studies demonstrated anti-tumor efficacy of the combination of the histone deacetylase (HDAC) inhibitor romidepsin plus erlotinib in non-small cell lung cancer (NSCLC) models that were insensitive to erlotinib monotherapy. We therefore studied this combination in a phase 1 clinical trial in previously treated advanced NSCLC.

METHODS

Romidepsin (8 or 10mg/m(2)) was administered intravenously on days 1, 8, and 15 every 28 days in combination with erlotinib (150 mg orally daily), with romidepsin monotherapy lead-in during Cycle 1. Correlative studies included peripheral blood mononuclear cell HDAC activity and histone acetylation status, and EGFR pathway activation status in skin biopsies.

RESULTS

A total of 17 patients were enrolled. Median number of prior lines of therapy was 3 (range 1-5). No cases had a sensitizing EGFR mutation. The most common related adverse events were nausea, vomiting, and fatigue (each 82%), diarrhea (65%), anorexia (53%), and rash (41%). Dose-limiting nausea and vomiting occurred at the romidepsin 10 mg/m(2) level despite aggressive antiemetic prophylaxis and treatment. Among 10 evaluable patients, the best response was stable disease (n=7) and progressive disease (n=3). Median progression-free survival (PFS) was 3.3 months (range 1.4-16.5 months). Prolonged PFS (>6 months) was noted in a KRAS mutant adenocarcinoma and a squamous cell cancer previously progressed on erlotinib monotherapy. Romidepsin monotherapy inhibited HDAC activity, increased histone acetylation status, and inhibited EGFR phosphorylation.

CONCLUSIONS

Romidepsin 8 mg/m(2) plus erlotinib appears well tolerated, has evidence of disease control, and exhibits effects on relevant molecular targets in an unselected advanced NSCLC population.

Molecular recognition of HER-1 in whole-blood samples

Multimode sensing was proposed for molecular screening and recognition of HER-1 in whole blood. The tools used for molecular recognition were platforms based on nanostructured materials such as the complex of Mn(III) with meso-tetra (4-carboxyphenyl) porphyrin, and maltodextrin (dextrose equivalence between 4 and 7), immobilized in diamond paste, graphite paste or C60 fullerene paste. The identification of HER-1 in whole-blood samples, at molecular level, is performed using stochastic mode and is followed by the quantification of it using stochastic and differential pulse voltammetry modes. HER-1 can be identified in the concentration range between 280 fg/ml and 4.86 ng/ml using stochastic mode, this making possible the early detection of cancers such as gastrointestinal, pancreatic and lung cancers. The recovery tests performed using whole-blood samples proved that the platforms can be used for identification and quantification of HER-1 with high sensitivity and reliability in such samples, these making them good molecular screening tools.

Tyrosine kinase inhibitors for epidermal growth factor receptor gene mutation-positive non-small cell lung cancers: an update for recent advances in therapeutics

The presence of activating gene mutations in the epidermal growth factor receptor of non-small cell lung cancer patients is predictive (improved progression-free survival and improved response rate) when treated with small molecule tyrosine kinase inhibitors such as gefitinib, erlotinib and afatinib. The two most common mutations that account for greater than 85% of all EGFR gene mutations are in-frame deletions in exon 19 (LREA deletions) and substitution in exon 21 (L858R). Exon 18 mutations occur much less frequently at about 4% of all EGFR gene mutations. Together, exon 19 deletion and exon 21 L858R gene substitution are present in about 10% of Caucasian patients and 20-40% of Asian patients with non-small cell lung cancer. T790M gene mutation at exon 20 is associated with acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors. Early studies showed that activating EGFR gene mutations are most common in patients with adenocarcinoma histology, women, never smokers and those of Asian ethnicity. A recent multi-center phase III trial suggested that frontline epidermal growth factor receptor tyrosine kinase inhibitor therapy with afatinib is associated with improved progression-free survival compared to chemotherapy regardless of race. Moreover, guidelines now suggest EGFR gene mutation testing should be conducted in all patients with lung adenocarcinoma or mixed lung cancers with an adenocarcinoma component, regardless of characteristics such as smoking status, gender or race. The success of targeted therapies in non-small cell lung cancer patients has changed the treatment paradigm in metastatic non-small cell lung cancer. However, despite a durable response of greater than a year, resistance to epidermal growth factor receptor tyrosine kinase inhibitors inevitably occurs. This mini-review describes the clinically relevant EGFR gene mutations and the efficacy/toxicity of small molecule epidermal growth factor receptor tyrosine kinase inhibitors as targeted therapies for these gene mutations. Therapeutic strategies to overcome resistance, including emerging and novel therapies, are discussed.

Trials to Overcome Drug Resistance to EGFR and ALK Targeted Therapies - Past, Present, and Future

Molecularly targeted agents are changing the therapeutic landscape in advanced non-small cell lung cancer. Since the discovery of sensitizing mutations in the epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) domain, clinical investigations have focused on optimizing the efficacy of EGFR and ALK tyrosine kinase inhibitors by addressing therapeutic resistance that commonly develops within a year of treatment initiation. Here, we review the clinical trials of novel therapies and combination regimens that have been undertaken in response to our evolving understanding of the mechanisms of resistance to targeted therapy. The aim of these trials was to enhance the therapeutic efficacy of targeted therapies by improving blockade and/or inhibiting parallel or compensatory signaling pathways. We have documented the sequential conduct of EGFR and ALK biomarker-driven trials in order to highlight particular pitfalls and successes, which should be considered in the design of future trials. Although there remain significant challenges, substantial gains have been made in our understanding of cellular resistance. This knowledge will drive the design of future trials to the benefit of lung cancer patients.

CKAP4 inhibited growth and metastasis of hepatocellular carcinoma through regulating EGFR signaling

CKAP4, one kind of type II trans-membrane protein, plays an important role to maintain endoplasmic reticulum structure and inhibits the proliferation of bladder cancer cells by combining its ligand anti-proliferative factor (APF). However, the biological function of CKAP4 in the progression of liver cancer has not been clearly demonstrated. In the present study, we knocked down or overexpressed CKAP4 in hepatocellular carcinoma (HCC) cells and cell proliferation, invasion, and migration capacities were investigated by CCK-8 and transwell assays. In vivo tumor model in mice was used to evaluate the role of CKAP4 on growth and metastasis of HCC. The data documented that HCC cells with high CKAP4 levels were featured by low proliferation capability as well as low invasion potential. Interestingly, we found that CKAP4 suppressed the activation of epithelial growth factor receptor (EGFR) signaling, which may partly explain the role of CKAP4 in cell biological behavior of HCC. Further study revealed that CKAP4 could associate with EGFR at basal status and the complex was reduced upon EGF stimulation, leading to release EGFR into cytoplasm. Thus, we demonstrate the novel mechanism, for the first time, expression of CKAP4 regulates progression and metastasis of HCC and it may provide therapeutic values in this tumor.

Targeted therapy for non-small-cell lung cancer: past, present and future

Therapy for advanced non-small-cell lung cancer has developed significantly with new awareness of histologic subtype as an important factor in guiding treatment and the development of targeted agents for molecular subgroups harboring critical mutations that spur on cancer growth. In this comprehensive review, we look back at developments in targeted therapy for advanced non-small-cell lung cancer, reviewing in detail efforts, both successful and in some cases less so, to target EGFR, VEGF and ALK. This review provides an overview of where the field stands at present and the areas we feel are most likely to provide challenges and potential successes in the next 5 years including immune checkpoint inhibition, epigenetic therapy and driver mutation targeting.

Ligand-conjugated mesoporous silica nanorattles based on enzyme targeted prodrug delivery system for effective lung cancer therapy

Epidermal growth factor receptor antibody (EGFRAb) conjugated silica nanorattles (SNs) were synthesized and used to develop receptor mediated endocytosis for targeted drug delivery strategies for cancer therapy. The present study determined that the rate of internalization of silica nanorattles was found to be high in lung cancer cells when compared with the normal lung cells. EGFRAb can specifically bind to EGFR, a receptor that is highly expressed in lung cancer cells, but is expressed at low levels in other normal cells. Furthermore, in vitro studies clearly substantiated that the cPLA2α activity, arachidonic acid release and cell proliferation were considerably reduced by pyrrolidine-2 loaded EGFRAb-SN in H460 cells. The cytotoxicity, cell cycle arrest and apoptosis were significantly induced by the treatment of pyrrolidine-2 loaded EGFRAb-SN when compared with free pyrrolidine-2 and pyrrolidine-2 loaded SNs in human non-small cell lung cancer cells. An in vivo toxicity assessment showed that silica nanorattles and EGFRAb-SN-pyrrolidine-2 exhibited low systemic toxicity in healthy Balb/c mice. The EGFRAb-SN-pyrrolidine-2 showed a much better antitumor activity (38%) with enhanced tumor inhibition rate than the pyrrolidine-2 on the non-small cell lung carcinoma subcutaneous model. Thus, the present findings validated the low toxicity and high therapeutic potentials of EGFRAb-SN-pyrrolidine-2, which may provide a convincing evidence of the silica nanorattles as new potential carriers for targeted drug delivery systems.

MUC15 inhibits dimerization of EGFR and PI3K-AKT signaling and is associated with aggressive hepatocellular carcinomas in patients

BACKGROUND & AIMS

Aberrant expression of MUC15 correlates with development of colorectal adenocarcinoma, and MUC15 has been reported to prevent trophoblast invasion of human placenta. However, little is known about the role of MUC15 in pathogenesis of hepatocellular carcinoma (HCC).

METHODS

We analyzed HCC samples and matched nontumor liver tissues (controls) collected from 313 patients who underwent hepatectomy in Shanghai, China, from January 2006 through September 2009. Levels of messenger RNAs and proteins were determined by immunohistochemical, quantitative reverse transcription polymerase chain reaction, and immunoblot analyses. Statistical analyses were used to associate levels of MUC15 with tumor features and patient outcomes.

RESULTS

Levels of MUC15 messenger RNA and protein were reduced in a greater percentage of HCC samples than control tissues. Tumors with reduced levels of MUC15 were more likely to have aggressive characteristics (eg, high levels of α-fetoprotein, vascular invasion, lack of encapsulation, and poor differentiation) than those with low levels. Patients whose tumors had reduced levels of MUC15 had shorter overall survival times (24 months vs 46 months for patients with tumors with high levels of MUC15) and time to disease recurrence. Stable expression of MUC15 in HCC cell lines (SMMC-7721 and HCC-LM3) reduced their proliferation and invasive features in vitro, and ability to form metastatic tumors in mice. MUC15 reduced transcription of the matrix metalloproteinases 2 and 7 increased expression of tissue inhibitor of metalloproteinase-2, which required phosphoinositide 3-kinase-v-akt murine thymoma viral oncogene homolog signaling. Physical interaction between MUC15 and epidermal growth factor receptor led to its relocation and degradation within early endosomes and was required for inactivation of phosphoinositide 3-kinase-v-akt murine thymoma viral oncogene homolog signaling.

CONCLUSIONS

Reduced levels of MUC15 in HCCs are associated with shorter survival times of patients and reduced time to disease recurrence. Expression of MUC15 in HCC cells reduces their aggressive behavior in vitro and in mice by inducing dimerization of epidermal growth factor receptor and decreasing phosphoinositide 3-kinase signaling via v-akt murine thymoma viral oncogene homolog.

Gefitinib versus placebo in completely resected non-small-cell lung cancer: results of the NCIC CTG BR19 study

PURPOSE

Survival of patients with completely resected non-small-cell lung cancer (NSCLC) is unsatisfactory, and in 2002, the benefit of adjuvant chemotherapy was not established. This phase III study assessed the impact of postoperative adjuvant gefitinib on overall survival (OS).

PATIENTS AND METHODS

Patients with completely resected (stage IB, II, or IIIA) NSCLC stratified by stage, histology, sex, postoperative radiotherapy, and chemotherapy were randomly assigned (1:1) to receive gefitinib 250 mg per day or placebo for 2 years. Study end points were OS, disease-free survival (DFS), and toxicity.

RESULTS

As a result of early closure, 503 of 1,242 planned patients were randomly assigned (251 to gefitinib and 252 to placebo). Baseline factors were balanced between the arms. With a median of 4.7 years of follow-up (range, 0.1 to 6.3 years), there was no difference in OS (hazard ratio [HR], 1.24; 95% CI, 0.94 to 1.64; P = .14) or DFS (HR, 1.22; 95% CI, 0.93 to 1.61; P = .15) between the arms. Exploratory analyses demonstrated no DFS (HR, 1.28; 95% CI, 0.92 to 1.76; P = .14) or OS benefit (HR, 1.24; 95% CI, 0.90 to 1.71; P = .18) from gefitinib for 344 patients with epidermal growth factor receptor (EGFR) wild-type tumors. Similarly, there was no DFS (HR, 1.84; 95% CI, 0.44 to 7.73; P = .395) or OS benefit (HR, 3.16; 95% CI, 0.61 to 16.45; P = .15) from gefitinib for the 15 patients with EGFR mutation-positive tumors. Adverse events were those expected with an EGFR inhibitor. Serious adverse events occurred in ≤ 5% of patients, except infection, fatigue, and pain. One patient in each arm had fatal pneumonitis.

CONCLUSION

Although the trial closed prematurely and definitive statements regarding the efficacy of adjuvant gefitinib cannot be made, these results indicate that it is unlikely to be of benefit.

Cross-talk between MET and EGFR in non-small cell lung cancer involves miR-27a and Sprouty2

In the past decade, we have observed exciting advances in lung cancer therapy, including the development of targeted therapies. However, additional strategies for early detection and tumor-based therapy are still essential in improving patient outcomes. EGF receptor (EGFR) and MET (the receptor tyrosine kinase for hepatocyte growth factors) are cell-surface tyrosine kinase receptors that have been implicated in diverse cellular processes and as regulators of several microRNAs (miRNAs), thus contributing to tumor progression. Here, we demonstrate a biological link between EGFR, MET, and the miRNA cluster 23a ~ 27a ~ 24-2. We show that miR-27a regulates MET, EGFR, and Sprouty2 in lung cancer. In addition, we identify both direct and indirect mechanisms by which miR-27a can regulate both MET and EGFR. Thus, we propose a mechanism for MET and EGFR axis regulation that may lead to the development of therapeutics in lung cancer.

A phase I trial of gefitinib and nimotuzumab in patients with advanced non-small cell lung cancer (NSCLC)

BACKGROUND

Nimotuzumab (TheraCIM®) is a humanized anti-epidermal growth factor receptor (EGFR) monoclonal antibody (mAb) with minimal skin toxicity. Combining a different class of anti-EGFR drug with gefitinib is a new strategy to overcome intrinsic and acquired resistance to gefitinib. The aim of this phase I trial was to determine recommended phase II dose (RPIID) and the safety of gefitinib and nimotuzumab combination treatment.

METHODS

Patients with advanced/metastatic NSCLC were treated with escalating doses of weekly nimotuzumab (100mg or 200mg, IV) and fixed doses of daily gefitinib (250 mg/day, PO) until disease progression or unacceptable toxicity. We planned to enroll 10 additional patients at RPIID to ascertain the safety of treatment. EGFR mutations and KRAS mutations were analyzed from available tumor samples.

RESULTS

A total of 16 patients were enrolled (3 in 100mg cohort, 13 in 200mg cohort). Six patients (37.5%) were female, and 5 (31.3%) were never smokers. Adenocarcinoma was the major histologic type (13 patients, 81.3%). Treatment was well-tolerated without dose-limiting toxicity (DLT). Four patients (25.0%) experienced grade 2 skin toxicity (1 in 100mg cohorts, 3 in 200mg cohort). Other common grade 1/2 toxicities were fatigue (37.5%) and diarrhea (25.0%). Among 16 evaluable patients, four patients (25.0%) achieved partial response and 7 patients (43.8%) had stable disease. Two of 4 responders had EGFR mutation (exon 19 deletion).

CONCLUSIONS

Dual agent molecular targeting of EGFR with nimotuzumab and gefitinib in patients with advanced NSCLC is well-tolerated. The RPIID for nimotuzumab is 200mg weekly IV and for gefitinib 250 mg/day PO. Based upon this phase I trial, we are planning to conduct a randomized phase II trial comparing gefitinib and nimotuzumab with gefitinib alone in patients with advanced NSCLC.

Modeling of tumor progression in NSCLC and intrinsic resistance to TKI in loss of PTEN expression

EGFR signaling plays a very important role in NSCLC. It activates Ras/ERK, PI3K/Akt and STAT activation pathways. These are the main pathways for cell proliferation and survival. We have developed two mathematical models to relate to the different EGFR signaling in NSCLC and normal cells in the presence or absence of EGFR and PTEN mutations. The dynamics of downstream signaling pathways vary in the disease state and activation of some factors can be indicative of drug resistance. Our simulation denotes the effect of EGFR mutations and increased expression of certain factors in NSCLC EGFR signaling on each of the three pathways where levels of pERK, pSTAT and pAkt are increased. Over activation of ERK, Akt and STAT3 which are the main cell proliferation and survival factors act as promoting factors for tumor progression in NSCLC. In case of loss of PTEN, Akt activity level is considerably increased. Our simulation results show that in the presence of erlotinib, downstream factors i.e. pAkt, pSTAT3 and pERK are inhibited. However, in case of loss of PTEN expression in the presence of erlotinib, pAkt level would not decrease which demonstrates that these cells are resistant to erlotinib.

Optimizing the use of epidermal growth factor receptor inhibitors in advanced non-small-lung cancer (NSCLC)

Lung cancer is the leading cause of cancer-related death in US and Europe. Treatment with a platinum-based chemotherapy remains the standard of care, however with modest effect on quality of life and overall survival which seldom reaches 1 year. Recently, several classes of targeted agents have emerged showing promising results. In particular, agents targeting the epidermal growth factor receptor (EGFR) showed impressive clinical activity both in the first line and salvage settings. However, it is evident that these drugs are not effective in all patients. Putting into consideration the very high cost of these agents, there is an urgent need to provide reliable tools to identify those patients that would derive the maximum benefit from these drugs. Several predictive biomarkers were developed to identify those patients who would derive the maximal benefit of these drugs. In this review we will discuss the recent updates on the role of EGFR inhibitors in the treatment of advanced NSCLC and the role of predictive bio-markers in patient selection.

Tankyrase and the canonical Wnt pathway protect lung cancer cells from EGFR inhibition

Lung cancer is the leading cause of death worldwide. Adenocarcinomas, the most common histologic subtype of non-small cell lung cancer (NSCLC), are frequently associated with activating mutations in the epidermal growth factor receptor (EGFR) gene. Although these patients often respond clinically to the EGFR tyrosine kinase inhibitors erlotinib and gefitinib, relapse inevitably occurs, suggesting the development of escape mechanisms that promote cell survival. Using a loss-of-function, whole genome short hairpin RNA (shRNA) screen, we identified that the canonical Wnt pathway contributes to the maintenance of NSCLC cells during EGFR inhibition, particularly the poly-ADP-ribosylating enzymes tankyrase 1 and 2 that positively regulate canonical Wnt signaling. Inhibition of tankyrase and various other components of the Wnt pathway with shRNAs or small molecules significantly increased the efficacy of EGFR inhibitors both in vitro and in vivo. Our findings therefore reveal a critical role for tankyrase and the canonical Wnt pathway in maintaining lung cancer cells during EGFR inhibition. Targeting the Wnt-tankyrase-β-catenin pathway together with EGFR inhibition may improve clinical outcome in patients with NSCLC.

Molecular biology of lung cancer: clinical implications

Lung cancer is a heterogeneous disease clinically, biologically, histologically, and molecularly. Understanding the molecular causes of this heterogeneity, which might reflect changes occurring in different classes of epithelial cells or different molecular changes occurring in the same target lung epithelial cells, is the focus of current research. Identifying the genes and pathways involved, determining how they relate to the biological behavior of lung cancer, and their utility as diagnostic and therapeutic targets are important basic and translational research issues. This article reviews current information on the key molecular steps in lung cancer pathogenesis, their timing, and clinical implications.

Targeted therapies for lung cancer: clinical experience and novel agents

Although lung cancer remains the leading cancer killer in the United States, recently a number of developments indicate future clinical benefit. These include evidence that computed tomography-based screening decreases lung cancer mortality, the use of stereotactic radiation for early-stage tumors, the development of molecular methods to predict chemotherapy sensitivity, and genome-wide expression and mutation analysis data that have uncovered oncogene "addictions" as important therapeutic targets. Perhaps the most significant advance in the treatment of this challenging disease is the introduction of molecularly targeted therapies, a term that currently includes monoclonal antibodies and small-molecule tyrosine kinase inhibitors. The development of effective targeted therapeutics requires knowledge of the genes and pathways involved and how they relate to the biologic behavior of lung cancer. Drugs targeting the epidermal growth factor receptor, anaplastic lymphoma kinase, and vascular endothelial growth factor are now U.S. Food and Drug Administration approved for the treatment of advanced non-small cell lung cancer. These agents are generally better tolerated than conventional chemotherapy and show dramatic efficacy when their use is coupled with a clear understanding of clinical data, mechanism, patient selection, drug interactions, and toxicities. Integrating genome-wide tumor analysis with drug- and targeted agent-responsive phenotypes will provide a wealth of new possibilities for lung cancer-targeted therapeutics. Ongoing research efforts in these areas as well as a discussion of emerging targeted agents being evaluated in clinical trials are the subjects of this review.

Prognostic value of epidermal growth factor receptor expression in operable non-small cell lung carcinoma

Background and aim

Increased expression of the epidermal growth factor receptor (EGFR) in non-small cell lung cancer (NSCLC), supporting the tumor growth by a possible endocrine mechanism, affects patient survival negatively. We designed a study to test EGFR expression by immunohistochemistry (IHC) in resected stage I-II NSCLC and to correlate its overexpression with survival.

Methods

EGFR expression was evaluated in 98 consecutive NSCLC patients after complete resection (53 squamous cell carcinomas, 40 adenocarcinomas, 5 large cell carcinomas: stage I, 57 (58%) and stage II, 41 (42%). IHC was used to examine the expression of EGFR in resected lung tumor samples obtained from these patients, who had no pre- or post-operative chemotherapy or radiotherapy. Univariate and multivariate analyses were performed for factors influencing patient survival.

Results

EGFR was expressed in 51 (52%) of 98 NSCLC samples. More squamous tumors (61%) were EGFR-positive than adenocarcinomas (38%) (p = 0.038). There was a statistically significant correlation between EGFR expression and stage (p = 0.04). No difference was found between EGFR positive and negative tumors in the 5-year overall survival (57% vs. 73%, p = 0.13).

Conclusion

The level of EGFR expression in tumors was not a successful predictor of survival in resected NSCLC.

Targeted therapy in non-small-cell lung cancer--is it becoming a reality?

Treatment outcomes in advanced or metastatic non-small-cell lung cancer (NSCLC) remain unsatisfactory, with low long-term survival rates. Palliative chemotherapy offers a median survival not exceeding 1 year. To date, various combinations of cytotoxic drugs have not improved treatment results beyond what has been observed with platinum doublets. By contrast, molecular targeted drugs may block important pathways that drive cancer progression and achieve long-term disease control. Conflicting results have demonstrated marginal benefit with EGFR inhibitors, anti-EGFR monoclonal antibodies and antiangiogenic strategies in unselected populations of patients with advanced NSCLC. However, patients with an EGFR mutation are likely to respond to agents that target this gene. Novel targeted therapies that interfere with insulin-like growth factor 1 receptor, or the EML4-ALK fusion protein have shown promising activity. Aberrations in other key signaling pathways and molecules, such as RAS/RAF/MEK, PI3K/AKT/mTOR, or MET kinase, have been identified as crucial targets, especially in resistant patients. Novel drugs aimed at these abnormalities are already in the clinic. This Review outlines the current state-of-the-art research for targeted therapy in NSCLC.

Epidermal growth factor receptor signaling in nonsmall cell lung cancer

Epidermal growth factor is a 170-kd protein that binds to a specific tyrosine kinase receptor, epidermal growth factor receptor (EGFR), on the cell surface. EGFR function is dysregulated in various malignancies including nonsmall cell lung cancer (NSCLC) leading to activation of several signal transduction pathways including K-RAS, PIK3, and STAT3 and STAT5, that promote cell cycle progression, proliferation, invasion, angiogenesis, and inhibit apoptosis. EGFR overexpression is seen in a majority of cases of NSCLC, but its prognostic role is controversial. EGFR inhibitors currently undergoing clinical trials in NSCLC include monoclonal antibodies or small molecule tyrosine kinase inhibitors. The only EGFR inhibitor currently approved for the treatment of NSCLC is erlotinib, a small molecule tyrosine kinase inhibitor. Although women, nonsmokers, patients with adenocarcinoma and patients with Asian ethnicity seem to have better outcomes with erlotinib, the factors predictive for response to these agents are currently the focus of investigation.

Standing the test of time in Europe? Gefitinib in the treatment of non-small-cell lung cancer

Lung cancer is the most common cancer worldwide, with 1.3 million new cases diagnosed every year. Non-small-cell lung carcinoma (NSCLC) has previously had a very poor prognosis with few effective therapies; however, research has identified that it is associated with a high rate of expression of epidermal growth factor receptor (EGFR) tyrosine kinase. This has led to discoveries in drug manipulation of this receptor, to provide effective new therapies against NSCLC. Gefitinib is a small molecule kinase inhibitor which inhibits the cytoplasmic domain of the EGFR; the evidence behind its use and future role is presented in this review.

Erlotinib treatment in pretreated patients with non-small cell lung cancer: A Phase II study

Erlotinib is an oral, small-molecule targeting therapy that inhibits epidermal growth factor tyrosine kinase receptors. Erlotinib has been administered for the treatment of advanced pancreatic cancer and non-small cell lung cancer. In the present trial, erlotinib was administered as second-line monotherapy in pretreated patients with advanced non-small cell lung cancer. Our objectives were to determine response, survival and toxicity. Fifty-four patients pretreated with cisplatin or its analogue-based combinations were evaluated. The disease stage of the patients was IIIB and IV. Thirty-eight patients were male, 16 were female, the median age was 65 years, and the WHO performance status was 0-2. Twenty-five cases were adenocarcinomas, 19 squamous cell carcinomas and 10 were undifferentiated. Erlotinib was administered at a dose of 150 mg daily. In case of intolerable adverse reactions, the dose was either reduced to 100 mg daily or treatment was interrupted for a maximum of two weeks. A partial response was observed in 10 (18.52%) and stable disease in 40 (74.07%) patients. The median time to disease progression was 3 months (95% CI 1.7-10.3), and the median survival was 6 months. Concerning toxicity, 53 patients (98.15%) developed a grade 1-2 skin rash, and 1 (1.85%) grade 3. Diarrhea occurred in 9 (16.67%) patients, nausea and vomiting in 4 (7.41%) and gastritis in 2 (3.70%). The majority of patients tolerated the erlotinib treatment. Of note were the 18.52% response rate and 74.07% stable disease.

Rationale of a relaunch of gefitinib in Caucasian non-small cell lung cancer patients

In 2002 results of two-phase II studies with the new epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) gefitinib showed not only promising efficacy in second and third line non-small cell lung cancer (NSCLC) therapies but also an excellent tolerability. Since then, thousands of patients have been treated in one of the largest expanded access programs ever performed and the successful application in daily routine led to a preliminary approval of the drug by the U.S. Food and Drug Administration in 2003. In the light of the negative results of a subsequent phase III trial comparing gefitinib with best supportive care, the approval was withdrawn. In 2009 gefitinib was relaunched for Caucasian patients in the US and Europe based on new data and on the re-interpretation of previous studies. The approval is now recommended exclusively for patients with an activating EGFR mutation. For the first time in lung cancer, molecular work-up is of clinical relevance and will change the diagnostic and therapeutic algorithms. The present review summarizes these data, presents the rationale for this development and proposes a diagnostic work-up.