Differential expression of epidermal growth factor receptor in human head and neck cancers

[Treatment of primary craniofacial (sinonasal) malignant tumors affecting the anterior and middle skull base]

Sinonasal malignant tumors are characterized by high histological variability and complexity of the differential diagnosis. Currently, there are classifications of these tumors, which are based on their localization and involvement of various anatomical structures. However, generally accepted algorithms for treatment of this pathology have not yet been developed. This review describes the most important algorithms for treatment of the most common histological variants of sinonasal malignant tumors: squamous cell carcinoma, adenocarcinoma, sinonasal undifferentiated carcinoma, esthesioneuroblastoma, adenoid cystic cancer, and sinonasal adenocarcinoma. The main problems in choosing the approach for treating these tumors are the lack of generally accepted resectability criteria and contradictions between oncological and neurosurgical indications for surgical treatment. Further research is needed to study the role of radiosensitizers and radioprotectors in comprehensive treatment of sinonasal malignant tumors.

Gefitinib (ZD1839) in Previously Treated Advanced Non-Small-Cell Lung Cancer: Experience from a Single Institution

BACKGROUND

We conducted an analysis of gefitinib in patients with advanced non-small-cell lung cancer (NSCLC) to assess the antitumor efficacy of this epidermal growth factor receptor tyrosine kinase inhibitor.

METHODS

Our single-center, prospective landmark analysis included 183 patients with advanced NSCLC who received 250 mg of gefitinib orally once daily in an expanded-use program at our institution. Thirty-three of the 183 patients were previously untreated. The patients included in this analysis had all received at least 12 weeks of gefitinib.

RESULTS

The objective tumor response rate was 3.8%, but an additional 53.5% of patients experienced clinically meaningful disease stabilization. Median progression-free survival time was 3.6 months, and median overall survival time was 8.8 months. The 1-year survival rate for the entire cohort was 35%. Predictors of longer survival included female gender, adenocarcinoma or bronchoalveolar carcinoma histology, and an Eastern Cooperative Oncology Group performance status of 0 or 1. Adverse events were generally mild (grade 1 or 2) and consisted mainly of skin reactions and diarrhea.

CONCLUSIONS

In this single-center experience, gefitinib demonstrated clinically significant antitumor activity and provided good palliation in a predominantly pretreated group of patients. Our results, which are likely to be reproducible in a community setting, demonstrated a 1-year survival rate of 35% in a cohort of patients who were able to take the drug for at least 12 weeks.

Prospects in the Application of Photodynamic Therapy in Oral Cancer and Premalignant Lesions

Oral cancer is a global health burden with significantly poor survival, especially when the diagnosis is at its late stage. Despite advances in current treatment modalities, there has been minimal improvement in survival rates over the last five decades. The development of local recurrence, regional failure, and the formation of second primary tumors accounts for this poor outcome. For survivors, cosmetic and functional compromises resulting from treatment are often devastating. These statistics underscore the need for novel approaches in the management of this deadly disease. Photodynamic therapy (PDT) is a treatment modality that involves administration of a light-sensitive drug, known as a photosensitizer, followed by light irradiation of an appropriate wavelength that corresponds to an absorbance band of the sensitizer. In the presence of tissue oxygen, cytotoxic free radicals that are produced cause direct tumor cell death, damage to the microvasculature, and induction of inflammatory reactions at the target sites. PDT offers a prospective new approach in controlling this disease at its various stages either as a stand-alone therapy for early lesions or as an adjuvant therapy for advanced cases. In this review, we aim to explore the applications of PDT in oral cancer therapy and to present an overview of the recent advances in PDT that can potentially reposition its utility for oral cancer treatment.

Cetuximab concurrent with IMRT versus cisplatin concurrent with IMRT in locally advanced nasopharyngeal carcinoma: A retrospective matched case-control study

To evaluate the treatment efficacies and toxicities of concurrent cetuximab-based bioradiotherapy (BRT) or cisplatin-based chemoradiotherapy (CRT) in locally advanced nasopharyngeal carcinoma. :Patients with previously untreated locally advanced nasopharyngeal carcinoma were matched into pairs, and enrolled into the study. All patients were given either BRT or CRT. Survival outcomes, toxicities, and prognostic factors were evaluated. :A total of 112 patients were enrolled. The 5-year overall survival was 79.3% and 79.5% in CRT and BRT arm, respectively (P = 0.797) and the 5-year DFS was 73.5% and 74.6%, respectively (P = 0.953). In toxicity analysis, CRT arm had more significant decrease in white blood cell, platelet, hemoglobin, and severe vomiting, while more severe skin reactions and mucositis were shown in BRT arm. :BRT was not less efficacious than traditional CRT. They lead to different aspects of toxicities. If patients cannot stand more severe toxicities caused by CRT, BRT could be an ideal alternative.

Short-term culture of tumour slices reveals the heterogeneous sensitivity of human head and neck squamous cell carcinoma to targeted therapies

Background

Despite recent progress, investigating the impact of targeted therapies on Head and Neck Squamous Cell Carcinoma (HNSCC) remains a challenge. We investigated whether short-term culture of tumour fragments would permit the evaluation of tumour sensitivity to targeted therapies at the individual level.

Methods

We cultivated tumour slices prepared from 18 HNSCC tumour samples obtained during surgical resection. The samples were treated for 48 h with a panel of 8 targeted therapies directed against selected oncogenic transduction pathways. We analysed the cell proliferation index (CPI) of tumour cells using Ki67 labelling and the activation status of the RAF-MEK-ERK cascade through ERK phosphorylation analysis.

Results

Fourteen tumours were successfully analysed after short-term culture of tumour samples, revealing a striking individual heterogeneity of HNSCC in terms of tumour cell sensitivity to targeted therapies. Using 50 % inhibition of CPI as threshold, sorafenib was shown to be active in 5/14 tumours. Cetuximab, the only approved targeted drug against HNSCC, was active in only 2/14 tumours. A more than 50 % inhibition was observed with at least one drug out of the eight tested in 10/14 tumours. Cluster analysis was carried out in order to examine the effect of the drugs on cell proliferation and the RAF-MEK-ERK cascade.

Conclusions

In vitro culture of tumour fragments allows for the evaluation of the effects of targeted therapies on freshly resected human tumours, and might be of value as a possible guide for the design of clinical trials and for the personalization of the medical treatment of HNSCC.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2318-x) contains supplementary material, which is available to authorized users.

mTOR inhibition induces EGFR feedback activation in association with its resistance to human pancreatic cancer

The mammalian target of rapamycin (mTOR) is dysregulated in diverse cancers and contributes to tumor progression and drug resistance. The first generation of mTOR inhibitors have failed to show clinical efficiency in treating pancreatic cancers due in part to the feedback relief of the insulin-like growth factor-1 receptor (IGF-1R)-AKT signaling pathway. The second generation of mTOR inhibitors, such as AZD8055, could inhibit AKT activation upon mTOR complex 2 (mTORC2) inhibition. However, whether this generation of mTOR inhibitors can obtain satisfactory activities in pancreatic cancer therapy remains unclear. In this study, we found AZD8055 did not show great improvement compared with everolimus, AZD8055 induced a temporal inhibition of AKT kinase activities and AKT was then rephosphorylated. Additionally, we found that AZD8055-induced transient AKT inhibition increased the expression and activation of epidermal growth factor receptor (EGFR) by releasing its transcriptional factors Fork-head box O 1/3a (FoxO1/3a), which might contribute to cell resistance to AZD8055. The in vitro and in vivo experiments further indicated the combination of AZD8055 and erlotinib synergistically inhibited the mTORC1/C2 signaling pathway, EGFR/AKT feedback activation, and cell growth, as well as suppressed the progression of pancreatic cancer in a xenograft model. This study provides a rationale and strategy for overcoming AZD8055 resistance by a combined treatment with the EGFR inhibitor erlotinib in pancreatic cancer therapy.

Strategies for non-resectable head and neck cancer

OPINION STATEMENT

Treatment of unresectable, locally advanced head and neck cancer consists of many different options, all of them based on radiotherapy. The main variable is represented by chemotherapy, i.e., the way in which chemotherapy is combined with radiation. More recently, the combination of cetuximab and radiotherapy emerged as a new treatment opportunity and induction chemotherapy, with the combination of docetaxel, cisplatin, and 5-fluoruracil, gained a renewed interest. Concurrent chemoradiation is based on the most robust evidence and is regarded as the leading standard of care for unresectable locally advanced head and neck cancer. Unfortunately, chemoradiation is hampered by severe toxicity and patients must be selected carefully before treatment. The experience of the staff (medical oncologists, radiation oncologists, and nurses), and in particular its familiarity with toxicity management, as well the structural facilities, play an important role in the final outcome. When the patient is unfit for chemoradiation, or when experienced staff or adequate structures are unavailable, induction chemotherapy, cetuximab and radiotherapy, or radiotherapy alone are all evidence-based alternative options. The choice among them will be based on the clinical condition of the patient, the physician's experience, and the patient's preference. Whatever is the treatment of choice, it is important to involve a multidisciplinary staff in the management of these patients. Indeed, also unresectable patients may require supportive surgical interventions before or during treatment, or removal of residual disease after treatment.

Targeted therapies in squamous cell carcinoma of the head and neck

Head and neck cancer is a challenging disease that is expected to account for greater than 500,000 new cases worldwide in 2008. Toxicity has impeded advances in chemotherapy and radiation for head and neck cancer, and the prognosis for patients with recurrent and/or metastatic disease remains poor. Over the past decade, clinical research in head and neck cancer has focused on improving the efficacy of current multimodal approaches by targeting cellular pathways associated with carcinogenesis. Blocking the epidermal growth factor receptor (EGFR) and the vascular endothelial growth factor receptor (VEGFR) have emerged as primary strategies that account for the success of current targeted therapies in cancer. Recent studies with cetuximab, a monoclonal antibody inhibitor of the EGFR, have demonstrated survival benefits across the range of treatment settings in advanced head and neck cancer, and it is the only targeted therapy approved for use in this malignancy. In this review, the authors present the current development status of targeted therapies, focusing on those that have potential to impact the management of head and neck cancer in the near-term future. Trials are ongoing in all stages of disease and with a variety of modalities and agents, and those trials should provide critical insight into the best way to use these agents to improve patient outcomes.

Drug Insight: cetuximab in the treatment of recurrent and metastatic squamous cell carcinoma of the head and neck

Patients with recurrent and/or metastatic squamous cell carcinoma of the head and neck (SCCHN) have a poor prognosis, particularly those whose disease has progressed on previous platinum-containing therapy. The epidermal growth factor receptor (EGFR) is expressed at very high levels in SCCHN and is associated with a poor prognosis. Several phase II-III studies have shown that the EGFR-targeting monoclonal antibody, cetuximab, offers clinical benefit for patients with SCCHN. Cetuximab monotherapy is active in patients whose cancer progresses on platinum-containing therapy. Tumor response and patient survival are in excess of what is achieved with commonly used therapies in this setting. Addition of a platinum regimen to cetuximab in patients with disease that progresses on platinum seems to confer no further benefit over cetuximab alone, either in terms of response rate or survival. In the first-line setting, cetuximab plus platinum and 5-fluorouracil significantly prolongs overall survival compared with platinum and 5-fluorouracil alone. The superior survival observed with cetuximab compared with platinum-based treatment demonstrates that cetuximab is the most active treatment for recurrent and/or metastatic SCCHN, and is of particular clinical significance.

Molecular contrast of EGFR expression using gold nanoparticles as a reflectance-based imaging probe

Advanced reflectance-based optical techniques for in vivo imaging often suffer from low contrast between neoplastic and normal tissue and are unable to image early biomolecular changes associated with carcinogenesis, thus limiting their clinical value. In this study, we exploit the resonance light scattering property of gold nanoparticles at their surface plasmon resonance to develop them as potential molecular contrast probes for imaging biomolecular changes during carcinogenesis under reflectance-mode imaging techniques. Gold nanoparticles were synthesized and conjugated to anti-epidermal growth factor receptor (EGFR). Their localization on the EGFR of nasopharyngeal carcinoma CNE2 cells and normal human lung fibroblast (NHLF) cells were imaged and compared under confocal microscopy in vitro. We have shown that the localization of gold bioconjugates on EGFR increases the reflectance properties of CNE2 cells and the regions of increased reflectance correspond to regions of high EGFR expression in the cells. The optical properties of normal fibroblast cells are not greatly affected. These gold bioconjugates are thus able to map the expression of relevant biomarkers and elicit an optical contrast for cancer cells over normal cells under confocal reflectance microscopy. Our study demonstrates the potential of gold nanoparticles to target and probe cancer cells and illuminates them for cancer detection under reflectance-based imaging systems based on biomolecular changes.

Expression of epidermal growth factor receptor in the inverted papilloma and squamous cell carcinoma of nasal cavity

The present study was undertaken to compare positive rate of immunostaining (PR) and positive intensity of immunostaining (PI) of epidermal growth factor receptor (EGFR) in inverted papilloma (IP), synchronous carcinoma with IP and metachronous carcinoma with IP of the nasal cavity. Ten subjects with nasal polyps, ten subjects with inverted papilloma (IP), five subjects with synchronous carcinoma with IP and ten subjects with metachronous carcinoma with IP were enrolled with a control group of ten subjects of inferior turbinate. Each specimen was divided into two portions: one for RNA isolation and the other for detection of EGFR protein. Positive rate of immunostaining, positive intensity of immunostaining for EGFR protein and EGFR mRNA were significantly up-regulated in the IP, synchronous carcinoma with IP and metachronous carcinoma with IP when comparing polyp and normal mucosa. A role for EGFR in the malignant transformation from IP to SCC of the nasal cavity is suggested.

ERBB receptors in developing, dysplastic and malignant oral epithelia

Some oral squamous cell carcinomas (OSCCs) overexpress epidermal growth factor receptor (EGFR) but little is known about the receptor system overall during oral carcinogenesis. We studied all four ERBB receptors (EGFR, ERBB2-4) in developing (n=2), normal (n=7), dysplastic (n=23) and malignant (n=26) oral epithelia by means of immunohistochemistry. The investigations were supplemented by conducting reverse transcription-polymerase chain reactions in relation to 13 OSCC samples. All four ERBB receptors were detected in developing oral epithelium and, to a lesser degree, in mature oral epithelium. An increase in EGFR immunoreactivity was seen in 61% and 54% of dysplasias and OSCCs, respectively. The corresponding percentages for ERBB2 were 48 and 12, for ERBB3 48 and 43. ERBB4 nuclear staining was increased in 30% of dysplasias and 26% of OSCCs. Changes in ERBB receptor mRNA levels were not statistically significant. The results show that ERBB receptor profiles are specific to each tumour. Increased nuclear translocation of ERBB4 in some OSCCs may alter transcription of target genes and be associated with cancer progression. This information may be useful for clinicians as EGFR inhibitors are becoming treatment options in modern oncology.

Phase I, Pharmacokinetic, and Biological Study of Erlotinib in Combination with Paclitaxel and Carboplatin in Patients with Advanced Solid Tumors

PURPOSE

To assess the feasibility of administering erlotinib, an inhibitor of epidermal growth factor receptor (EGFR) tyrosine kinase, in combination with paclitaxel and carboplatin, and to identify pharmacokinetic interactions, evaluate downstream effects of EGFR inhibition on surrogate tissues, and seek preliminary evidence for clinical activity.

EXPERIMENTAL DESIGN

Patients with advanced solid malignancies were treated continuously with erlotinib at doses of 100, 125, and 150 mg/d orally along with fixed i.v. doses of paclitaxel 225 mg/m(2) and carboplatin AUC 6 mg x min/mL, both on day 1 every 3 weeks.

RESULTS

Twenty evaluable patients were treated with 136 courses of erlotinib, paclitaxel, and carboplatin. Myelosuppression, skin rash, and diarrhea were the principal toxicities. Dose limiting diarrhea occurred in 1 of 6 patients at the 100 mg erlotinib dose level, whereas 0 of 9 evaluable patients at the 125 mg erlotinib dose level experienced dose limiting toxicity and 3 of 5 evaluable patients at 150 mg erlotinib experienced dose limiting skin rash and neutropenic sepsis. There was no evidence of pharmacokinetic interactions between paclitaxel and erlotinib; however, total carboplatin exposure trended higher in the presence of erlotinib. No consistent downstream effects on EGFR inhibition were found in skin. Durable objective responses were observed in non-small-cell lung and head and neck cancers.

CONCLUSIONS

A dose level of erlotinib 125 mg combined with paclitaxel 225 mg/m(2) and carboplatin AUC 6 mg.min/mL is recommended for disease-directed studies. This phase I trial was followed by a randomized phase III study in non-small-cell lung cancer using a similar regimen.

Reactive oxygen species regulate epidermal growth factor-induced vascular endothelial growth factor and hypoxia-inducible factor-1alpha expression through activation of AKT and P70S6K1 in human ovarian cancer cells

The epidermal growth factor (EGF) and EGF receptor (EGFR) family are often overexpressed in various human cancers including ovarian cancer. While it is generally believed that reactive oxygen species (ROS) are involved in the intracellular signaling events, the role of ROS in EGF-induced angiogenesis and carcinogenesis remains to be elucidated. The present study investigated the role of ROS in the regulation of AKT, p70S6K1, vascular endothelial growth factor (VEGF), and hypoxia-inducible factor 1 (HIF-1) in ovarian cancer cells. In this study, OVCAR-3 cells were treated with EGF and catalase, an H2O2 scavenger. EGF treatment increases H2O2 production, leading to activation of the AKT/p70S6K1 pathway, resulting in increased VEGF expression at the transcriptional level. The inhibition of H(2)O(2) production by catalase abolished EGF-induced AKT and p70S6K1 activation, and VEGF expression through HIF-1alpha expression. Forced expression of p70S6K1 and HIF-1alpha reversed catalase- and rapamycin-inhibited VEGF transcriptional activation. We also showed that rapamycin, p70S6K1 inhibitor and catalase overexpression inhibited tumor angiogenesis. This study demonstrates a novel mechanism of EGF-induced VEGF and HIF-1alpha expression through production of H2O2 and activation of AKT and p70S6K1 in human ovarian cancer cells. This study also indicates that p70S6K1 and H2O2 are important in tumor angiogenesis. The results of the study could have an important implication in ovarian cancer therapy.

Detection of the molecular changes associated with oral cancer using a molecular-specific fluorescent contrast agent and single-wavelength spectroscopy

There is currently no standard screening technique for oral cancer and its precursors other than visual identification and biopsy of suspicious lesions. To aid noninvasive early detection of oral neoplasia in vivo, we previously developed a molecular-specific contrast agent targeted against epidermal growth factor receptor. Here, we present a simple fluorescence spectroscopy system to detect the presence of this contrast agent in biological models representative of living tissues in order to demonstrate the feasibility of using a spectroscopy system in conjunction with a contrast agent as a screening technique for oral cancer. The spectroscopy system was tested for the ability to detect the contrast agent in four in vitro models: multilayer tissue phantoms made of cells pre-labeled with the contrast agent, multilayer tissue phantoms labeled with the contrast agent from the surface in conjunction with a permeability enhancing agent, fresh tissue slices from normal and abnormal oral cavity biopsies, and whole normal and abnormal oral cavity biopsies. The optical signal from samples labeled with the contrast agent was 3--32 times stronger compared to controls and was detected with a signal-to-noise ratio greater than 10. These results demonstrate that an inexpensive and simple spectroscopy system can be used in biological models of living systems to detect the optical signal from a contrast agent targeted toward a cancer-related biomarker with good signal-to-noise ratios. Coupling inexpensive fluorescence spectrometers with molecular-specific contrast agents has the potential to improve the early detection of oral neoplasia by providing a low-cost screening tool.

Mechanism of action of potato carboxypeptidase inhibitor (PCI) as an EGF blocker

The epidermal growth factor receptor (EGFR) signal transduction pathway plays a prominent role in the development of carcinomas, and is an interesting target for antitumoral therapy. We have previously described how potato carboxypeptidase inhibitor (PCI), a 39-amino acid protease inhibitor with a T-Knot motif, binds to EGFR receptor and inhibits the activation of receptor protein tyrosine kinase. In this paper it is shown that PCI interferes with EGFR activation through inhibition of receptor dimerization and receptor transphosphorylation induced by epidermal growth factor (EGF) and by transforming growth factor alpha (TGF-alpha). Moreover, PCI blocks the formation and activation of ErbB1/ErbB-2 heterodimers that have a prominent role in carcinoma development. As a result of these effects, PCI interferes in the EGFR signal transduction pathway by reversing the effects of EGF on the growth of two tumoral cell lines, A431 and MDA-MB-453, and promotes EGFR down-regulation. These results show that PCI acts as an EGF/TGF-alpha antagonist, which suggests its therapeutic potential in the treatment of carcinomas.

Salivary epidermal growth factor in oral cavity cancer

Salivary epidermal growth factor (EGF) effect on oral cancer biology is unknown. We examined changes in minute volumes of whole resting and stimulated saliva, EGF concentration and its output (ELISA) in whole resting and stimulated saliva before and 2 weeks after surgical treatment in oral carcinoma patients compared to the control group. After stimulation salivary flow increased both in the control (P=0.003) and in the patients group--before (P=0.007) and after surgery (P=0.005). Higher stimulated saliva volume levels were observed before surgery than in post-treatment patients (P=0.032). A trend was seen with increasing EGF salivary concentrations after tumour excision both in resting (P=0.508) and stimulated (P=0.647) saliva. A similar ascending tendency of EGF output in stimulated saliva of post-treatment patients was observed (P=0.878). Decreased levels of EGF concentration in saliva before and its contrary tendency after surgical treatment may suggest an important role of EGF in oral cancer tumourogenesis.

Molecular biological design of novel antineoplastic therapies

Novel therapies represent a new strategy for the development of anticancer agents. New targets derived from the knowledge of the molecular structure and genetic defects has been useful in developing anticancer drugs that prolong or stabilise the progression of tumours with minimal systemic toxicities. In this review, the mechanism of action and the most significant trials regarding monoclonal antibodies, tyrosine kinase inhibitors, angiogenesis and cyclooxygenase inhibitor-based therapies, farnesyl transferase inhibitors and proteasome inhibitors are discussed. The potential biological end points and toxicities are also described. In conclusion, novel therapies present a promising class of anticancer agents, acting through different mechanisms and offering a new perspective in the treatment of cancer.

A new immune-competent animal model of mucosally derived squamous cell carcinoma

OBJECTIVES

To develop an immune-competent animal model for mucosally derived squamous cell carcinoma (SCCA).

STUDY DESIGN

Fifteen Fischer 344 rats were inoculated with 1, 2, 5, 10, or 20 x 10(6) FAT7 cells in their flanks. The animals were observed for tumor growth and metastasis.

RESULTS

All animals developed tumors that grew exponentially. Pulmonary metastases developed in all animals and 13% developed lymph node metastases.

CONCLUSION

The FAT7 flank tumor in Fischer 344 rats is a new animal model that closely resembles the behavior of human mucosal head and neck cancer.

SIGNIFICANCE

The existence of an immune-competent, mucosally derived, and reliable animal model of SCCA that somewhat resembles human head and neck SCCA gives the opportunity to perform immune-modulating experiments on head and neck cancer in these animals.

EBM RATING

B-3.

Novel management of oral cancer: a paradigm of predictive oncology

The rationale for molecular-targeted prevention of oral cancer is strong. Oral cancer is a major global threat to public health with 300,000 new cases diagnosed worldwide on an annual basis. Notably, the great morbidity and mortality rates of this devastating disease have not improved in decades. Oral cancer development is a tobacco-related multistep and multifocal process involving field carcinogenesis and intraepithelial clonal spread. Biomarkers of genomic instability, such as aneuploidy and allelic imbalance, can accurately measure the cancer risk of oral premalignant lesions or intraepithelial neoplasia (IEN). Retinoid-oral IEN studies (e.g., retinoid acid receptor-beta, p53, genetic instability, loss of heterozygosity, and cyclin D1) have advanced the overall understanding of the biology of intraepithelial carcinogenesis and preventive agent molecular mechanisms and targets, important advances for monitoring preventive interventions, assessing cancer risk, and pharmacogenomics. Clinical management of oral IEN varies from watchful waiting to complete resection, although complete resection does not prevent oral cancer in high-risk patients. New approaches, such as interventions with molecular-targeted agents and agent combinations in molecularly defined high-risk oral IEN patients, are urgently needed to reduce the devastating worldwide consequences of oral cancer.

Immunohistochemical detection of EGFR in paraffin-embedded tumor tissues: variation in staining intensity due to choice of fixative and storage time of tissue sections

The epidermal growth factor receptor (EGFR) is highly expressed in a variety of solid malignant tumors and its expression has been correlated with disease progression and poor survival. With the advent of targeted therapies, especially IMC-C225 (Cetuximab), a monoclonal antibody (MAb) directed against the EGFR, there is an increasing interest in immunohistochemistry (IHC)-based EGFR screening methods using paraffin-embedded tumor specimens to select cancer patients eligible for treatment with Cetuximab. With the EGFRpharmDX kit, a complete assay for demonstration of EGFR is now available. Because no information about the preservation of the EGFR under various conditions of fixation is available, we performed a prospective study on a panel of commonly used fixatives to determine optimal tissue preservation protocols. The stability of the epitope on cut tissue sections stored for a period up to 24 month was also tested using material originating from patients with head and neck cancer, non-small-cell lung carcinomas, and colorectal adenocarcinomas. Depending on the fixative used and the time of storage of cut tissue sections, a variation in the determined level of EGFR expression was demonstrated compared with the most optimal fixation procedure.

Advances in Chemoprevention of Head and Neck Cancer

Head and neck squamous cell carcinoma is a devastating disease with a poor outcome in advanced stages, accounting for approximately 3% of all malignancies, with an estimated 37200 new cases and 11000 deaths annually in the U.S. Second primary tumors are estimated to occur at an annual rate of 3%-10% and are significant threats to long-term survivors. Chemoprevention is an appealing strategy, and its success has been demonstrated in breast cancer and familial adenomatous polyposis. High-dose retinoids have been shown to be active against oral premalignant lesions and in prevention of second primary tumors in the head and neck. New targets include the epidermal growth factor receptor, cyclooxygenase-2, and other molecular targets. Challenges in future head and neck cancer chemoprevention investigations include achieving long-lasting efficacy with retinoids and/or new agents, and determining the optimal dose and duration of therapy while maintaining acceptable toxicities.

Combination therapy with gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, gemcitabine and cisplatin in patients with advanced solid tumors

BACKGROUND

The aim of this study was to investigate the tolerability, pharmacokinetic interaction and antitumor activity of gefitinib ("Iressa", ZD1839), an orally active, selective epidermal growth factor receptor tyrosine kinase inhibitor, combined with gemcitabine and cisplatin in chemotherapy-naïve patients with advanced solid tumors.

PATIENTS AND METHODS

This was an open-label feasibility trial evaluating two doses of gefitinib (250 and 500 mg/day) in combination with gemcitabine and cisplatin. Gefitinib was administered daily from day 2 onwards. Gemcitabine 1250 mg/m(2) was given on days 1 and 8 and cisplatin 80 mg/m(2) on day 1 for up to six 3-week cycles. Patients could then continue to receive gefitinib monotherapy.

RESULTS

Eighteen patients were entered, nine at each gefitinib dose level. Two patients developed dose-limiting toxicity: one grade 3 convulsion (250 mg/day dose group) and one grade 3 rash (500 mg/day dose group). The most frequently occurring adverse events in the combination phase were vomiting (17 patients), asthenia (16), nausea (14), diarrhea (14) and skin rash (13). The most common grade 3/4 adverse events were vomiting (seven patients), asthenia (six), thrombocytopenia (six), diarrhea (five) and anorexia (five). Pharmacokinetic analyses showed no apparent pharmacokinetic interaction between gefitinib and cisplatin or gemcitabine, with the exception of a possible small increase in the geometric mean exposure to gemcitabine seen on day 8 of therapy when given alone with the higher dose of gefitinib. Of 17 evaluable patients, nine had confirmed partial responses, seven had stable disease and one had progressive disease.

CONCLUSIONS

Combination therapy of gefitinib with cisplatin and gemcitabine had a manageable and predictable safety profile, no major effect on exposure to any of the three drugs and antitumor activity.

Pharmacodiagnostic Value of the HER Family in Head and Neck Squamous Cell Carcinoma

Two protooncogene products, EGFR (Her-1, c-erbB-1) and HER2 (Her-2/neu, c-erbB-2), have been reported to be frequently overexpressed in head and neck squamous cell carcinoma (HNSCC). In order to identify patients who may benefit from targeted cancer treatment for these two molecules, we determined the expression status of EGFR and HER2 in 129 HNSCC tumor specimens. Two pharmacodiagnostic kits (EGFR pharmDx and HercepTest) were used to identify HNSCC tumors that overexpress EGFR or HER2. Overexpression of EGFR was detected in 42.6% of the tumor specimens, while HER2 was only rarely expressed (overexpression was observed in just 3.1% of all cases). Given the necessity of new therapeutic modalities for patients suffering from HNSCC, treatment EGFR signaling inhibitors appears to be warranted, whereas therapeutic intervention with HER2 inhibitors seems to be inappropriate in this tumor type.

Cetuximab in cancers of the lung and head & neck

The treatment of aerodigestive tract tumors remains difficult despite improved techniques in detection, surgery, radiation, and chemotherapy. Therefore, strategies to improve efficacy in accord with safety are needed. The epidermal growth factor receptor has become a target of increasing interest. Cetuximab is a monoclonal antibody targeting this receptor. A series of phase I and II studies of cetuximab in combination with radiotherapy or chemotherapy have been conducted initially to determine the optimal biological dose (ie, tumor epidermal growth factor receptor-saturating dose) and to establish a safety profile with cetuximab in combination with other antitumor agents. Ultimately, these therapies may become valuable contributors in the treatment of head and neck cancer and lung cancer. This report will focus specifically on the epidermal growth factor receptor and cetuximab.

Signal transduction--directed cancer treatments

The pathogenic mechanisms giving rise to cancer frequently involve altered signal transduction pathways. Therefore therapeutic agents that directly address signal transduction molecules are being explored as cancer treatments. Inhibitors of protein tyrosine and threonine kinases including STI-571, ZD-1839, OSI-774, and flavopiridol are ATP-site antagonists that have completed initial phase I and phase II evaluations. Herceptin and C225 are monoclonal antibodies also directed against signaling targets. Numerous other kinase antagonists are in clinical evaluation, including UCN-01 and PD184352. Alternative strategies to downmodulate kinase-driven signaling include 17-allyl-amino-17-demethoxygeldanamycin and rapamycin derivatives, and phospholipase-directed signaling may be modulated by alkylphospholipids. Farnesyltransferase inhibitors were originally developed as inhibitors of ras-driven signals but may have activity by affecting other or additional targets. Signal transduction will remain a fertile basis for suggesting cancer treatments of the future, the evaluation of which should include monitoring effects of the drugs on their intended target signaling molecules in preclinical and early clinical studies.

Differentiation-dependent expression of signal transducers and activators of transcription (STATs) might modify responses to growth factors in the cancers of the head and neck

Overexpression of the epidermal growth factor receptor (EGFR) in the cancers of the head and neck is well demonstrated. In addition, copy numbers of the EGFR mRNA were significantly higher in poorly differentiated tumors than in tumors that had a differentiated phenotype. Studies by others also showed that the constitutively activated signal transducer and activator of transcription-3 (STAT3), but not STAT1, is required for EGFR-mediated cell growth. Our aim was to reveal if STAT expression is differentiation-dependent and thus, might respond to exogenous stimuli in a differentiation-dependent manner. Both reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry revealed that expression of STAT1 was high in well/moderately differentiated tumors in vivo. In contrast, STAT3 was expressed in poorly differentiated tumors. In vitro experiments showed that differentiated primary oral keratinocytes expressed higher levels of STAT1, but lower levels of STAT3 than did their undifferentiated counterparts. Epidermal growth factor treatment of oral keratinocytes with various degrees of differentiation showed the maximal induction of cyclin D1 in undifferentiated cells. Our findings suggest that the level of differentiation might modulate the outcome of EGFR signaling (i.e. cyclin D1 transcription), due to the differentiation-associated intracellular balance of transcriptional regulators (STAT1 versus STAT3).

Novel approaches with targeted therapies in bladder cancer. Therapy of bladder cancer by blockade of the epidermal growth factor receptor family

The improved understanding of the molecular biology of urothelial malignancies is helping to define the role of new targets and prognostic indices that can direct the most appropriate choice of treatment for advanced disease. Many human tumors express high levels of growth factors and their receptors that can be used as potential therapeutical targets. Tyrosine-kinase receptors, including many growth factor receptors such the receptors for epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), and Her2/neu, have been found overexpressed in urothelial tumors. For many of these growth factor receptors, the degree of expression has been associated with the progression of cancer and a poor prognosis. Among the best studied growth factor receptors are the two members of EGF receptor familiy EGFr (ErbB-1), and Her2/neu (ErbB-2). Several preclinical studies in bladder cancer models, have confirmed that systemic administration of growth factor inhibitors inhibits the growth and metastasis of human transitional cell carcinoma established in the bladder wall of athymic nude mice. Additional studies indicate that therapy with EGFR inhibitors enhances the activity of conventional cytoreductive chemotherapeutic agents, in part by inhibiting tumor cell proliferation, angiogenesis, and inducing apoptosis. Novel targeted therapy hold promise to improve the current results of bladder cancer treatment. Based on the success seen with anti-HER2 monoclonal antibodies (Herceptin) and the promising results with EGFR targeted agents (IMC-C225 Cetuximab, ZD1389 Iressa, OSI-774 Tarceva, GW 57016) in other tumor types, and based on the results obtained in preclinical models, there is a great interest in assessing these agents in patients with bladder cancer. Several trials are now ongoing testing these new agents alone or in combination with chemotherapy in bladder cancer patients. The integration of these newer biologic agents, probably to supplement rather than to supplant chemotherapeutic drugs, should be a primary direction of research with the objective to interfere with multiple aspects of bladder cancer progression. However, the value of integration of biologically targeted agents into combined modality treatment for patients with bladder cancer has still to be proven.

Treatment of metastatic head and neck cancer: chemotherapy and novel agents

For more than a decade, the de facto "standard of care" for palliative mangement of recurrent head/neck squamous carcinoma (HNSCC) has been the combination of cisplatin/5-flourouracil. With the advent of new cytotoxins, such as the taxanes, and of the molecularly targeted agents, eg., the EGFR inhibitors, the number of options for treatment in this setting has increased. However, none of these new approaches has yet been proven to be more effective than cisplatin/5-fluorouracil. Further, despite the pallitive intent of therapy in this setting, the palliative effects have been only infrequently assessed, with many studies relying on response as a surrogate for palliation. This chapter will focus on clinical and translational research efforts in the past decade focusing on the patient with incurable locoregionally recurrent or metastatic HNSCC. Ongoing and planned future trails will also be discussed.

The role of epidermal growth factor receptor in head and neck squamous cell carcinoma

Growth factor receptors play a crucial role in the cell proliferation pathways involved in the development of cancer. One such receptor, the epidermal growth factor receptor (EGFR), is upregulated in many types of human tumors, particularly head and neck squamous cell carcinoma (HNSCC). EGFR overexpression in HNSCC has been the basis for investigation of therapeutic strategies that target EGFR. EGFR-blocking methods under evaluation involve immunotoxins, monoclonal antibodies, EGFR-specific tyrosine kinase inhibitors, and antisense approaches. These molecular targeting tactics have produced a number of agents that are currently in various stages of preclinical investigation, along with clinical trials to assess their potential as anticancer treatments.

ZD1839, a selective oral epidermal growth factor receptor-tyrosine kinase inhibitor, is well tolerated and active in patients with solid, malignant tumors: results of a phase I trial

PURPOSE

To investigate the tolerability, pharmacokinetics, and antitumor activity of the oral, selective epidermal growth factor receptor-tyrosine kinase inhibitor ZD1839 in patients with solid malignant tumors.

PATIENTS AND METHODS

This was an open, phase I, escalating multiple-dose tolerability and pharmacokinetic trial. ZD1839 was administered once daily for 14 consecutive days followed by 14 days off treatment. Dose escalation started at 50 mg/d and continued to 925 mg or until consistent dose-limiting toxicity (DLT) was observed.

RESULTS

Sixty-four patients were entered at eight dose levels. The most frequent dose-related grade 1 and 2 adverse events were an acne-like (or folliculitis) rash, nausea, and diarrhea. Three of nine patients treated at 700 mg/d developed DLT (reversible grade 3 diarrhea); grade 3 and 4 events were uncommon. Exposure to ZD1839 was dose proportional, and the mean terminal half-life was 48 hours (range, 37 to 65). Four of 16 patients with non-small-cell lung cancer (NSCLC) had objective partial responses observed from ZD1839 300 to 700 mg/d. Overall, 16 patients remained on study for > or = 3 months, with seven of these patients (five with NSCLC, including three of the patients with partial response) remaining on study for > or = 6 months.

CONCLUSION

ZD1839 was well tolerated, with DLT observed at a dose well above that at which antitumor activity was seen. Pharmacokinetic analysis confirmed that ZD1839 was suitable for administration as a once-daily oral tablet formulation. Phase II monotherapy and phase III combination trials in NSCLC are being conducted to investigate further the efficacy, tolerability, and optimal daily dose of ZD1839.

Novel therapeutics for head and neck cancer

Head and neck squamous cell carcinoma is a clinically challenging disease that resulted in more than 500,000 cases worldwide in 2001. In the United States, head and neck squamous cell carcinoma has accounted for approximately 40,000 cases with 12,000 deaths reported in 2001, which makes it the fifth leading cause of cancer incidence and the sixth leading cause of cancer-related deaths. Patients with recurrent or metastatic disease have a median survival rate of approximately 6 months; and there is little evidence from randomized trials that survival advantages have been achieved over the community standard of cisplatin and infusional 5-fluorouracil combination. Despite significant improvements in diagnosis, local management, and chemotherapy of head and neck cancer, there has been no significant increase in long-term survival rates over the past 30 years. As little progress has been made, new management approaches are required. Novel biologic agents have been developed to target multiple specific regions of the cancer cell. Epidermal growth factor receptor blockers have been investigated, such as anti epidermal growth factor receptor monoclonal antibodies, tyrosine kinase inhibitors, ligand conjugates, immunoconjugates, and antisense oligonucleotides. Farnesyl transferase inhibitors are a class of compounds that inhibit a critical enzymatic step in the constitutive expression of mutated ras genes, which are present in more than 27% of oral cancers. Strategies targeting the p53 gene and protein may halt or reverse the process of tumorigenesis and metastasis as p53 mutations occur in 45 to 70% of head and neck squamous cell carcinoma patients. Continued development of these novel agents may help improve the overall response and survival rate of patients with head and neck cancer.

Monoclonal antibodies to target epidermal growth factor receptor-positive tumors: a new paradigm for cancer therapy

BACKGROUND

Traditional cytotoxic approaches to tumor management are associated with efficacy and toxicity limitations. Blockade of the epidermal growth factor receptor (EGFR) and its ligands is a novel approach to the treatment of human tumors that offers a noncytotoxic alternative to cancer treatment.

METHODS

An English-language literature search was conducted to identify studies assessing the in vitro and in vivo effects of EGFR blockade with an emphasis on approaches that use monoclonal antibody therapy.

RESULTS

The EGF pathway regulates normal cellular processes and appears to be correlated with the development of malignancy. Approximately 30% of human tumors express EGFR, which has been reported to be correlated with poor prognosis and diminished disease-free and overall survival in selected tumor types. A number of anti-EGFR monoclonal antibodies have been developed, which currently are undergoing clinical trials in humans. Effective anti-EGFR monoclonal antibodies compete with endogenous ligands, primarily EGF and transforming growth factor-alpha, for receptor ligand-binding sites. Binding to EGFR blocks critical signaling pathways and interferes with the growth of tumors expressing EGFR. Anti-EGFR monoclonal antibodies that currently are under study include IMC-C225, EMD 55900, ICR 62, and ABX-EGF.

CONCLUSIONS

These antibodies have demonstrated promising results and appear to have been well tolerated. EGFR-targeted therapy addresses important, unmet needs in the treatment of human tumors, particularly EGFR-positive epithelial tumors including common malignancies of the head and neck, lung, and colon.

The unexplained survival of cells in oral cancer: what is the role of p53?

In normal oral epithelium the cells divide, mature, differentiate, and die. This sequence is not normally followed in oral cancer. Instead, the death of the cells is somehow prevented, although the pathways toward cell death in normal oral epithelium and the defects in oral cancer are not well defined. However, several components in the system have been identified, and information on their interactions is becoming available. This review summarizes the evidence for cell death being due to apoptosis and the central role of the p53 gene product in its regulation. Areas for future research are also identified.

Selected novel anticancer treatments targeting cell signaling proteins

Empirical approaches to discovery of anticancer drugs and cancer treatment have made limited progress in the cure of cancer in the last several decades. Recent advances in technology and expanded knowledge of the molecular basis of tumorigenesis and metastasis have provided unique opportunities to design novel compounds that rationally target the abnormal molecular and biochemical signals leading to cancer. Several such novel agents have completed advanced stages in clinical development. The excellent clinical results achieved by some of these compounds are creating new paradigms in management of patients with neoplastic diseases. Clinical development of these agents also raises challenges to the traditional methods of drug evaluation and measurement of efficacy.

Advanced diagnostic methods in oral and maxillofacial pathology. Part II: immunohistochemical and immunofluorescent methods

The practice of pathology is currently undergoing significant change, in large part due to advances in the analysis of DNA, RNA, and proteins in tissues. These advances have permitted improved biologic insights into many developmental, inflammatory, metabolic, infectious, and neoplastic diseases. Moreover, molecular analysis has also led to improvements in the accuracy of disease diagnosis and classification. It is likely that, in the future, these methods will increasingly enter into the day-to-day diagnosis and management of patients. The pathologist will continue to play a fundamental role in diagnosis and will likely be in a pivotal position to guide the implementation and interpretation of these tests as they move from the research laboratory into diagnostic pathology. The purpose of this 2-part series is to provide an overview of the principles and applications of current molecular biologic and immunologic tests. In Part I, the biologic fundamentals of DNA, RNA, and proteins and methods that are currently available or likely to become available to the pathologist in the next several years for their isolation and analysis in tissue biopsies were discussed. In Part II, advances in immunohistochemistry and immunofluorescence methods and their application to modern diagnostic pathology are reviewed.

Epidermal growth factor receptor biology (IMC-C225)

Treatment of solid tumors despite improved techniques in detection, surgery, radiation therapy, and chemotherapy remains difficult. Therefore, strategies to improve efficacy in accord with safety are needed. Many epithelial cancers have been found to overexpress the receptor to epidermal growth factor (EGFR), including head and neck, breast, colon, lung, prostate, kidney, ovary, brain, pancreas, and bladder. Because overexpression of EGFR has been associated with an overall poor prognosis in patients with cancer, a number of strategies to block or downregulate EGFR have been developed to inhibit tumor proliferation and improve overall clinical outcome. These include monoclonal antibodies to the EGFR, tyrosine kinase inhibitors, ligand-linked toxins, and antisense approaches. Antibodies such as IMC-C225 specifically target EGF receptors, whereas tyrosine kinase inhibition by many small molecules is less specific. Ultimately, IMC-C225 may prove to become a valuable contributor in the treatment of cancer. This report will focus on IMC-C225, a novel monoclonal antibody that targets the EGFR.

Expression of protease-activated receptor 1 in oral squamous cell carcinoma

Protease-activated receptor 1 (PAR-1) is a G-coupled membrane protein. In this study, we analyzed the expression of PAR-1 in oral squamous cell carcinomas (SCCs). PAR-1 was expressed in oral SCCs, but the level of PAR-1 protein was lower in non-metastatic cells than in metastatic cells. Thrombin stimulated the growth of metastatic cells, and both thrombin and thrombin receptor activation peptide (TRP) enhanced the adhesion of these cells to fibronectin, but had no effect on non-metastatic cells. Thrombin and TRP also induced matrix metalloproteinase (MMP)-2 and MMP-9 activities in metastatic cells. These results suggest that PAR-1 may contribute to the growth and invasive potential of oral SCC.

IMC-C225, an anti-epidermal growth factor receptor monoclonal antibody, for treatment of head and neck cancer

Squamous cell carcinoma (SCC) of the head and neck (H&N) remains a clinical challenge due to its high rate of locoregional disease recurrence. The importance of the epidermal growth factor receptor (EGFR) in the development and progression of many solid tumours (including SCC of the H&N) is well understood; increased expression is associated with enhanced tumour invasion, resistance to chemotherapy and decreased patient survival. Several approaches have been developed to achieve EGFR blockade as an anticancer treatment strategy, including an anti-EGFR monoclonal antibody (mAb), IMC-C225, which competitively binds to the extracellular receptor site to prevent binding by natural EGFR ligands (EGF and TGF-alpha). Preclinical studies evaluating this chimeric mAb in human cancer cell lines in vitro and human tumour xenografts in vivo have demonstrated its potent antitumour activity. The clinical efficacy of IMC-C225 appears to involve multiple anticancer mechanisms, including inhibition of cell cycle progression, induction of apoptosis, anti-angiogenesis, inhibition of metastasis and its ability to enhance the response to chemotherapy and radiation therapy. Phase I studies of IMC-C225 combined with chemotherapy or radiation for SCC of the H&N demonstrate excellent response rates in patients with recurrent or refractory disease. Phase II and III trials examining the efficacy and safety of these combinations are currently underway. To date, IMC-C225 has been well-tolerated, with skin rashes and allergic reactions being the most clinically important adverse events reported. IMC-C225 displays dose-dependent elimination characteristics and a half-life of approximately 7 days. Current recommendations for dosing include a 400 mg/m2 loading dose, followed by weekly infusions of 250 mg/m2.

Differential expression of a novel serine protease homologue in squamous cell carcinoma of the head and neck

Differential gene expression between squamous cell carcinoma of the head and neck and matched normal tissue was studied by utilizing Representational Difference Analysis. Using this methodology, a novel gene, DESC1 was isolated. DESC1 possesses strong identity to the serine protease super-family. Comparison of DESC1 expression between primary squamous cell carcinoma and matched normal tissue shows that the level of DESC1 expression is reduced or absent in 11/12 SCC tissue specimens when compared to specimens of matched normal tissue. Tissue-specific expression studies further show that DESC1 expression can only be detected in tissues derived from the head and neck, and in skin, prostate and testes. Cell line studies demonstrate that DESC1 expression is epithelial-specific. Chromosomal localization studies indicate that DESC1 is located on the long arm of chromosome 4 at position q12-13.