Epidermal growth factor receptor inhibitors in non-small-cell lung cancer

The epidermal growth factor receptor (EGFR) is a cell membrane receptor that plays a key role in cancer development and in the progression of many human malignancies, including non-small-cell lung cancer (NSCLC). EGFR-dependent signaling is involved in cancer cell proliferation, apoptosis, angiogenesis, invasion and metastasis. Targeting the EGFR is a valuable molecular approach in cancer therapy. This receptor is overexpressed in up to 80% of NSCLC cases. Thus, several molecules inhibiting this critical biologic pathway have been synthesized and tested as a single agent or in combination with other anticancer modalities in a wide of clinical trials, including reversible and irreversible small tyrosine kinase inhibitors, such as gefitinib and erlotinib, dual vascular endothelial growth factor receptor EGFR tyrosine kinase inhibitors, such as vandetanib (ZD-6474), and monoclonal antibodies, such as cetuximab, which have shown promising activity in patients with NSCLC. This review focuses on the preclinical and clinical results available with EGFR inhibitors in the treatment of NSCLC patients.     

EGFR抑制剂耐药机制研究的新进展

表皮生长因子受体(EGFR)通路在肿瘤发生、发展过程中起到非常重要的作用,它已成为肿瘤分子治疗领域最主要的研究和开发靶点之一。目前有单克隆抗体与小分子受体酪氨酸激酶抑制剂两类EGFR抑制剂在临床治疗中取得成功。然而,该类药物在临床前研究及临床治疗中已经出现耐药现象。由于EGFR调节多种细胞功能,该耐药现象可能与多个传导通路紊乱有关,包括配体自分泌/旁分泌的产生、受体突变、下游信号蛋白的组成性活化以及旁路信号途径的激活。本文就EGFR抑制剂耐药机制的最新研究进展进行综述。     

Epidermal growth factor receptor tyrosine kinase inhibitors as anticancer agents

The epidermal growth factor receptor (EGFR)-driven autocrine growth pathway has been implicated in the development and progression of the majority of the most common human epithelial cancers, making the blockade of this growth pathway a promising anticancer therapeutic strategy. Different approaches have been developed to block EGFR activation and/or function in cancer cells. In the past 15 years, various anti-EGFR blocking monoclonal antibodies (MAb), recombinant proteins containing transforming growth factor-alpha (TGFalpha) or EGF fused to toxins, and tyrosine kinase inhibitors (TKIs) have been generated and their biological and potentially therapeutic properties characterised. One of these agents, MAb IMC-C225, a chimeric human-mouse IgG1 MAb, is the first anti-EGFR agent to enter phase II to III clinical trials in patients with cancer. Several small compounds that block the ligand-induced activation of the EGFR tyrosine kinase have been developed. Among these EGFR-TKIs, various quinazoline-derived agents have been synthesised and have shown promising activity as anticancer agents in preclinical models. ZD1839 ('Iressa'), an anilinoquinazoline, is an orally active, selective EGFR-TKI which is currently under clinical evaluation in phase II to III clinical trials in patients with cancer. Preclinical data for ZD1839 strongly support the possibility of potentiating the antitumour activity of conventional chemotherapy with agents that selectively block the EGFR.     

Adding to the mix: fibroblast growth factor and platelet-derived growth factor receptor pathways as targets in non-small cell lung cancer

The treatment of advanced non ? small cell lung cancer (NSCLC) increasingly involves the use of molecularly targeted therapy with activity against either the tumor directly, or indirectly, through activity against host-derived mechanisms of tumor support such as angiogenesis. The most well studied signaling pathway associated with angiogenesis is the vascular endothelial growth factor (VEGF) pathway, and the only antiangiogenic agent currently approved for the treatment of NSCLC is bevacizumab, an antibody targeted against VEGF. More recently, preclinical data supporting the role of fibroblast growth factor receptor (FGFR) and platelet-derived growth factor receptor (PDGFR) signaling in angiogenesis have been reported. The platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF) pathways may also stimulate tumor growth directly through activation of downstream mitogenic signaling cascades. In addition, 1 or both of these pathways have been associated with resistance to agents targeting the epidermal growth factor receptor (EGFR) and VEGF. A number of agents that target FGF and/or PDGF signaling are now in development for the treatment of NSCLC. This review will summarize the potential molecular roles of PDGFR and FGFR in tumor growth and angiogenesis, as well as discuss the current clinical status of PDGFR and FGFR inhibitors in clinical development.     

Molecularly targeted therapy for gastrointestinal cancer

Receptor and non-receptor tyrosine kinases (TKs) have emerged as clinically useful drug target molecules for treating gastrointestinal cancer. Imatinib mesilate (STI-571, Gleevec(TM)), an inhibitior of bcr-abl TK, which was primarily designed to treat chronic myeloid leukemia is also an inhibitor of c-kit receptor TK, and is currently the drug of choice for the therapy of metastatic gastrointestinal stromal tumors (GISTs), which frequently express constitutively activated forms of the c-kit-receptor. The epidermal growth factor receptor (EGFR), which is involved in cell proliferation, metastasis and angiogenesis, is another important target. The two main classes of EGFR inhibitors are the TK inhibitors and monoclonal antibodies. Gefitinib (ZD1839, Iressa(TM)) has been on trial for esophageal and colorectal cancer (CRC) and erlotinib (OSI-774, Tarceva(TM)) on trial for esophageal, colorectal, hepatocellular, and biliary carcinoma. In addition, erlotinib has been evaluated in a Phase III study for the treatment of pancreatic cancer. Cetuximab (IMC-C225, Erbitux(TM)), a monoclonal EGFR antibody, has been FDA approved for the therapy of irinotecan resistant colorectal cancer and has been tested for pancreatic cancer. Vascular endothelial growth factor (VEGF) and its receptor (VEGFR) are critical regulators of tumor angiogenesis. Bevacizumab (Avastin(TM)), a monoclonal antibody against VEGF, was efficient in two randomized clinical trials investigating the treatment of metastatic colorectal cancer. It is also currently investigated for the therapy of pancreatic cancer in combination with gemcitabine. Other promising new drugs currently under preclinical and clinical evaluation, are VEGFR2 inhibitor PTK787/ZK 222584, thalidomide, farnesyl transferase inhibitor R115777 (tipifarnib, Zarnestra(TM)), matrix metalloproteinase inhibitors, proteasome inhibitor bortezomib (Velcade(TM)), mammalian target of rapamycin (mTOR) inhibitors, cyclooxygenase-2 (COX-2) inhibitors, platelet derived growth factor receptor (PDGF-R) inhibitors, protein kinase C (PKC) inhibitors, mitogen-activated protein kinase kinase (MEK) 1/2 inhibitors, Rous sarcoma virus transforming oncogene (SRC) kinase inhibitors, histondeacetylase (HDAC) inhibitors, small hypoxia-inducible factor (HIF) inhibitors, aurora kinase inhibitors, hedgehog inhibitors, and TGF-beta signalling inhibitors.     

Promising molecular targeted therapies in breast cancer

In recent years, there has been a significant improvement in the understanding of molecular events and critical pathways involved in breast cancer. This has led to the identification of novel targets and development of anticancer therapies referred to as targeted therapy. Targeted therapy has high specificity for the molecules involved in key molecular events that are responsible for cancer phenotype such as cell growth, survival, migration, invasion, metastasis, apoptosis, cell-cycle progression, and angiogenesis. Targeted agents that have been approved for breast cancer include trastuzumab and lapatinib, directed against human epidermal growth factor receptor 2 (HER2) and bevacizumab, directed against vascular endothelial growth factor (VEGF). Several other targeted agents currently under evaluation in preclinical and clinical trials include inhibitors of epidermal growth factor receptor (EGFR), dual EGFR and HER2 inhibitors, VEGF/VEGFR inhibitors, and agents that interfere with crucial signaling pathways such as PI3K/AKT/mTOR and RAS/MEK/ERK; agents against other tyrosine kinases such as Src, insulin-like growth factor (IGF)/IGF-receptor (IGFR); agents that promote apoptosis such as Poly ADP ribose polymerase inhibitors; agents that target invasion and metastasis such as matrix metalloproteinases inhibitors and others. In this review, we highlight the most promising targeted agents and their combination with mainstream chemotherapeutic drugs in clinical trials.     

Antitumor therapeutic strategies based on the targeting of epidermal growth factor-induced survival pathways

Cellular receptors for the Epidermal Growth Factor are considered important targets for the experimental treatment of human cancer. Monoclonal antibodies as well as small tyrosine kinase inhibitors have been developed and have undergone extensive evaluation in preclinical and clinical studies. Most of these studies have been conceived on the general idea that epidermal growth factor receptor (EGFR) plays a critical role on the growth and survival of human tumors. This assumption has been derived by the successful development of BCR/ABL tyrosine kinase inhibitors in human chronic myeloid leukemia as well as on the activity of antiCD20 monoclonal antibodies in lymphoproliferative disease and of anti HER2 agents in breast tumors overexpressing the targeted antigens. It is now becoming clear that factors regulating sensitivity to kinase inhibitors may differ from monoclonal antibodies and that the molecules targeted by interferring drugs must be prioritaire for growth and survival of those specific tumors in order to achieve valuable results. Recent evidence of major responses to the EGFR inhibitor Gefitinib in tumors harboring activating mutations in the EGFR appears on line with this concept. In this article we will discuss the significance of targeting the EGFR driven survival pathways. Specifically, we will afford the point of EGFR survival signalling prioritization by means of pharmacological treatment. Finally, we will address the role of profiling technologies and of novel computational system biology-based approaches for identification of innovative strategies for effective targeting of EGFR driven survival pathways.     

Targeting the EGFR signaling pathway in cancer therapy

Introduction: Cancer is a devastating disease; however, several therapeutic advances have recently been made, wherein EGFR and its family members have emerged as useful biomarkers and therapeutic targets. EGFR, a transmembrane glycoprotein is a member of the ERBB receptor tyrosine kinase superfamily. EGFR binds to its cognate ligand EGF, which further induces tyrosine phosphorylation and receptor dimerization with other family members leading to enhanced uncontrolled proliferation. Several anti-EGFR therapies such as monoclonal antibodies and tyrosine kinase inhibitors have been developed, which has enabled clinicians to identify and treat specific patient cohorts. Areas covered: This review covers the basic mechanism of EGFR activation and the role of EGFR signaling in cancer progression. Furthermore, current developments made toward targeting the EGFR signaling pathway for the treatment of epithelial cancers and a summary of the various anti-EGFR therapeutic agents that are currently in use are also presented in this review. Expert opinion: EGFR signaling is a part of a complex network that has been the target of effective cancer therapies. However, a further understanding of the system is required to develop an effective anticancer regimen. A combination therapy that comprises an anti-EGFR and a chemotherapeutic/chemopreventive agent will exhibit a multi-pronged approach that can be developed into a highly attractive and specific molecular oriented remedy.     

The epidermal growth factor receptor in malignant gliomas: pathogenesis and therapeutic implications

Activated epidermal growth factor receptor (EGFR) has emerged as an important therapeutic target for a variety of solid tumors, particularly malignant gliomas. Mutation or amplification of EGFR is commonly observed in malignant gliomas and these modifications are associated with increased cell proliferation and radiation resistance. Small-molecule kinase inhibitors targeting the intracellular kinase domain of the EGFR and monoclonal antibodies against the extracellular domain of the EGFR have demonstrated in vitro efficacy and have spawned clinical trials incorporating EGFR inhibition into the management of malignant gliomas, for example, combining EGFR inhibitors with radiation therapy. This early clinical experience indicates that EGFR inhibitors are well tolerated; however, it remains unclear how best to integrate EGFR inhibition into the management of malignant gliomas. As signaling pathways become better defined, patients may be treated with EGFR inhibitors based on the molecular features of their tumors and treatment efficacy may be improved by combining EGFR inhibition with other small kinase inhibitors and radiation therapy.     

The epidermal growth factor receptor in malignant gliomas: pathogenesis and therapeutic implications

Activated epidermal growth factor receptor (EGFR) has emerged as an important therapeutic target for a variety of solid tumors, particularly malignant gliomas. Mutation or amplification of EGFR is commonly observed in malignant gliomas and these modifications are associated with increased cell proliferation and radiation resistance. Small-molecule kinase inhibitors targeting the intracellular kinase domain of the EGFR and monoclonal antibodies against the extracellular domain of the EGFR have demonstrated in vitro efficacy and have spawned clinical trials incorporating EGFR inhibition into the management of malignant gliomas, for example, combining EGFR inhibitors with radiation therapy. This early clinical experience indicates that EGFR inhibitors are well tolerated; however, it remains unclear how best to integrate EGFR inhibition into the management of malignant gliomas. As signaling pathways become better defined, patients may be treated with EGFR inhibitors based on the molecular features of their tumors and treatment efficacy may be improved by combining EGFR inhibition with other small kinase inhibitors and radiation therapy.     

Rational combination of targeted therapies as a strategy to overcome the mechanisms of resistance to inhibitors of EGFR signaling

The epidermal growth factor receptor (EGFR) has been widely used as a target for novel anticancer agents, such as blocking antibodies and small molecular weight tyrosine kinase compounds. In spite of recent advances in cancer cell biology, leading to the introduction of clinically active new drugs, such as cetuximab, panitumumab and erlotinib, unfortunately disease control remains unsuccessful due to the presence of constitutive resistance to EGFR inhibitors in most patients and the development of acquired resistance in the responders. A large number of molecular abnormalities in tumor cells seem to partly contribute to their resistance to anti-EGFR therapy: increased angiogenesis, constitutive activation of downstream mediators, overexpression of other tyrosine kinase receptors. Moreover, some mutations in the EGFR receptor kinase domain seem to play a crucial role in determining the sensitivity of cancer cells to specific inhibitors by altering the conformation of the receptor and its activity. The development of rational combinations of anticancer agents and EGFR inhibitors, able to exert synergistic cytotoxic interactions, has been widely accepted and used in both preclinical and clinical studies. Although the failure of large clinical trial based on empirical combination of anti-EGFR and classic chemotherapeutic agents, several preclinical data seems to support the hypothesis that combining EGFR inhibitors and other novel agents could efficiently inhibit tumor growth and overcome intrinsic resistance to a single-agent based therapy. This review focuses on the role of complementary signalling pathways in the development of resistance to EGFR targeting agents and the rationale to combine novel inhibitors as anticancer therapy.     

Signal transduction inhibitors in the treatment of breast cancer

Signal transduction pathways are frequently altered in human breast cancer and are the targets of several novel therapies currently in clinical trials. Therapeutic strategies include extracellular blockade of tyrosine kinase receptors with the monoclonal antibodies C225 and trastuzumab. Competitive inhibitors of adenosine triphosphate binding sites on tyrosine and serine/threonine kinases are also being evaluated in phase I/II trials; these include ZD1839, OSI-774 and CI-1033. Flavopiridol and UCN-01 are nonspecific cell cycle kinase antagonists with preliminary evidence of breast cancer cell growth inhibition. Several inhibitors of mitogen-activated protein kinase and phosphatidylinositol 3-kinase signaling are also in various stages of preclinical or clinical development. Additionally, inhibitors of farnesyl transferase have demonstrated activity in breast cancer cells irrespective of ras status. Current evidence suggests that targeting of signaling molecules is a promising new approach to treatment of breast cancer.     

Insulin-like growth factor-1 receptor (IGF-1R) kinase inhibitors in cancer therapy: advances and perspectives

The insulin-like growth factors (IGF) and their receptors play pivotal roles in cellular signaling transduction and thus regulate cell growth, differentiation, apoptosis, transformation and other important physiological progresses. The insulin-like growth factor 1 receptor (IGF-1R) mainly engages in the Ras/mitogen-activated protein kinase (MAPK) pathway and the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway, and also forms cross-talk with the epidermal growth factor receptor (EGFR) pathway. Currently, it draws more attention since its overexpression has been demonstrated in various human cancers, such as colorectal cancer, breast cancer, prostate cancer and lung tumors, thus the strategy targeting the IGF-1R would be promising in treatment of these cancers. There are already dozens of agents developed for the inhibition of IGF-1R, which are categorized into monoclonal antibodies, small molecule inhibitors and so on. While in this review, small molecule inhibitors would be the focus for detailed discussion. Herein, we updated previously reported research papers and reviews in this field and summarized developments of small molecule inhibitors up to 2011. Finally, we proposed the application of network pharmacology methods to reconsider the clinical use of inhibitors with concomitant IR inhibition or other kinases inhibition, hoping that more optimal combinations would be obtained for cancer therapy.     

EGFR, HER2 and VEGF pathways: validated targets for cancer treatment

Targeted therapies are rationally designed to interfere with specific molecular events that are important in tumour growth, progression or survival. Several targeted therapies with anti-tumour activity in human cancer cell lines and xenograft models have now been shown to produce objective responses, delay disease progression and, in some cases, improve survival of patients with advanced malignancies. These targeted therapies include cetuximab, an anti-epidermal growth factor receptor (EGFR) monoclonal antibody; gefitinib and erlotinib, EGFR-specific tyrosine kinase inhibitors; trastuzumab, an anti-human EGFR type 2 (HER2)-related monoclonal antibody; lapatinib, a dual inhibitor of both EGFR- and HER2-associated tyrosine kinases; and bevacizumab, an anti-vascular endothelial growth factor (VEGF) monoclonal antibody.On the basis of preclinical and clinical evidence, EGFR, HER2 and VEGF represent validated targets for cancer therapy and remain the subject of intensive investigation. Both EGFR and HER2 are targets found on cancer cells, whereas VEGF is a target that acts in the tumour microenvironment. Clinical studies are focusing on how to best incorporate targeted therapy into current treatment regimens and other studies are exploring whether different strategies for inhibiting these targets will offer greater benefit. It is clear that optimal use of targeted therapy will depend on understanding how these drugs work mechanistically, and recognising that their activities may differ across patient populations, tumour types and disease stages, as well as when and how they are used in cancer treatment. The results achieved with targeted therapies to date are promising, although they illustrate the need for additional preclinical and clinical study.     

Everolimus: targeted therapy on the horizon for the treatment of breast cancer

The mammalian target of rapamycin (mTOR) is a signaling kinase of the phosphatidylinositol 3-kinase/protein kinase B (also known as Akt) signaling pathway that mediates cell growth and metabolism. Dysregulation of the mTOR pathway creates a favorable environment for the development and progression of many cancers, including breast cancer, and is associated with the development of resistance to endocrine therapy and to the anti-human epidermal growth factor receptor-2 (HER2) monoclonal antibody trastuzumab. Therefore, the addition of mTOR inhibitors to conventional breast cancer therapy has the potential to enhance therapeutic efficacy and/or overcome innate or acquired resistance. Everolimus, an mTOR inhibitor with demonstrated preclinical activity against breast cancer cell lines, has been shown to reverse Akt-induced resistance to hormonal therapy and trastuzumab. Phase I-II clinical trials have demonstrated that everolimus has promising clinical activity in women with HER2-positive, HER2-negative, and estrogen receptor-positive breast cancer when combined with HER2-targeted therapy, cytotoxic chemotherapy, and hormonal therapy, respectively. Everolimus is generally well tolerated; hematologic abnormalities and stomatitis are most common adverse events when this drug is combined with cytotoxic chemotherapy. Based on these promising results, everolimus is currently under evaluation in a series of phase III Breast Cancer Trials of Oral Everolimus (BOLERO) trials of women with HER2-positive and estrogen receptor-positive breast cancer. Results of these trials will help to establish the role of everolimus in the treatment of clinically important breast cancer subtypes.     

以EGFR家族受体酪氨酸激酶为靶点的抗肿瘤治疗研究进展

表皮生长因子受体 (EGFR)家族的受体酪氨酸激酶与多种恶性肿瘤的发生、发展及预后等密切相关。近年来 ,许多以此为靶点的新的抗肿瘤药物和治疗方法陆续被开发 ,主要有单克隆抗体、双特异性抗体、小分子酪氨酸激酶抑制剂和基因治疗等。它们有的已进入临床试验 ,耐受性良好 ,并且在多种肿瘤治疗中取得了令人鼓舞的疗效     

Insulin-like growth factor signaling as a therapeutic target in pancreatic cancer

Insulin-like growth factor-1 (IGF-1) leads via its receptor IGF-1R to the activation of the PI3K/Akt pathway, providing antiapoptotic signals to pre-malignant and malignant cells. In pancreatic cancer, IGF-1 and its receptor are constitutively overexpressed. Mammalian target of rapamycin (mTOR) is the main mediator of mitogenic stimuli transduced by PI3K/Akt. Interestingly, inhibition of mTOR activates PI3K/Akt by up-regulating IGF-1R signaling. Several targeted agents have been developed to inhibit the activity of IGF-1 or to block IGF-1R. These pharmaceuticals may offer additional ways of stimulating apoptosis in neoplastic cells. Yet, there are difficulties in targeting this pathway: The ideal anti-cancer drug target is expressed only in cancer cells; however, IGF-1 and its receptor IGF-1R are ubiquitously expressed throughout the body. Moreover, when using antibodies against IGF-1R, the structurally similar insulin receptor might also be blocked, leading to hyperglycemia as a severe side effect. There are currently several phase I/II trials investigating IGF-1 and its receptor as a drug target in various kinds of cancer. Specifically, therapeutic effects on pancreatic cancer by combining a humanized monoclonal antibody against IGF-1R with other chemotherapeutics are being investigated. To improve the clinical outcome of mTOR inhibitors such as everolimus, it has been suggested to use combination therapies of mTOR inhibitors and IGF-1/IGF-1R inhibitors. In theory, this would counterbalance the feedback effects of mTOR inhibition on IGF-1 signaling. In conclusion, IGF-1 and its receptor are promising new drug targets in cancer therapy. Combination therapies of IGF-1/IGF-1R inhibitors and mTOR inhibitors could improve the clinical outcome.     

Anti-epidermal growth factor receptor drugs in cancer therapy

The epidermal growth factor receptor is a cell membrane growth factor receptor that plays a key role in cancer development and progression. Epidermal growth factor receptor-activated signalling pathways control cell proliferation, apoptosis, angiogenesis and metastatic spread in the majority of human epithelial cancers. Targeting the epidermal growth factor receptor represents a valuable molecular approach to cancer therapy. Promising strategies in clinical development include monoclonal antibodies which block ligand binding and small molecule inhibitors of the tyrosine kinase enzymatic activity which prevent epidermal growth factor receptor autophosphorylation and propagation of downstream intracellular signals. Several anti-epidermal growth factor receptor agents are in clinical development for cancer therapy. Among these, IMC-225 (cetuximab), a chimeric human-mouse monoclonal IgG1 antibody, OSI-774 (Tarceva) and ZD1839 (Iressa), two small molecule epidermal growth factor receptor-selective tyrosine kinase inhibitors, are currently in Phase II and III development as single agents or in combination with conventional therapies, such as radiotherapy or chemotherapy. Results from Phase I - II trials in advanced cancer demonstrate that these drugs have an acceptable tolerability and an interesting clinical activity in patients with a variety of tumour types.     

Resistance to epidermal growth factor receptor-targeted therapy.

The epidermal growth factor receptor (EGFR) has been a major target of molecular anticancer therapy. Two approaches have been developed, involving monoclonal antibodies and receptor tyrosine kinase inhibitors, and both have demonstrated benefit in clinical trials. However, evidence of resistance to these drugs has been described. Cellular levels of EGFR do not always correlate with response to the EGFR tyrosine kinase inhibitors, indicating acquired resistance to these drugs. Since EGFR antagonists interfere with the activation of several intracellular pathways that control cell proliferation, survival, apoptosis, angiogenesis, invasion and metastasis, acquired resistance can occur as a result of several different molecular mechanisms: autocrine/paracrine production of ligand, receptor mutation, constitutive activation of the downstream pathway and activation of alternative pathways. We will describe here potential mechanisms that can cause resistance to EGFR-targeted drugs. Combinations of EGFR antagonists with inhibitors targeting different signaling mechanism(s) - such as insulin-like growth factor receptor and vascular endothelial growth factor receptor - that share the same downstream mediator (e.g., phosphatidylinositol 3-kinase/Akt, mitogen-activated protein kinase), may circumvent or delay the development of resistance to EGFR antagonists resulting in enhanced antitumor activities.     

Targeting EGFR in pancreatic cancer treatment

The prognosis of patients with pancreatic cancer is extremely poor, and current systemic therapies provide marginal survival benefits for treated patients. The era of targeted therapies has offered a new avenue to search for potentially more effective strategies. Epidermal growth factor receptor (EGFR) is a member of the erbB/human epidermal growth factor receptor family of tyrosine kinases, which includes erbB2/HER2, erbB3/HER3 and erbB4/HER4. Epidermal growth factor receptor overexpression may be detected in up to 90% of pancreatic tumors. Two pharmacologic approaches have been successfully used to inhibit epidermal growth factor receptor function in cancer treatment: neutralizing monoclonal antibodies and small molecule tyrosine inhibitors. The randomized trials studying the addition of EGFR targeted agents to gemcitabine compared with gemcitabine alone have been disappointing, although results with the EGFR tyrosine kinase inhibitor erlotinib were statistically significant but clinically of marginal benefit. In this article, we review the epidermal growth factor receptor signaling network in pancreatic cancer, the strategies to increase the effectiveness of epidermal growth factor receptor inhibitors, and the clinical trials of these inhibitors in pancreatic cancer.