Epidermal growth factor receptors in lung tumours

In Vivo and in Vitro Growth of SCLC Cells Derived from Biopsies

In order to increase the availability of SCLC cells derived from biopsies, in vivo and in vitro growth methods were investigated. The cells grown in both conditions were periodically monitored for reactivity with 2 monoclonal antibodies (MAbs): MLuC1 directed against SCLC cells and IM1 which recognizes the class II antigen on activated lymphocytes and macrophages. About 50 % of the 28 analyzed SCLC specimens were found to proliferate in one or both systems. The in vitro-grown cells exhibited the same heterogeneity found in the original cell suspensions and moreover, in some cases only normal cells were recovered after several in vitro passages. From the subcutaneous transplanted tumors a large number of MLuC1-positive tumor cells could easily be recovered, thus indicating the validity of the in vivo methodology. The MBr1 MAb, directed against an epithelial antigen, was found to react with about 50 % of the 26 tested tumors, mainly those which demonstrated in vivo and/or in vitro growth capacity. These data suggest that only some tumors, presumably with peculiar biological characteristics, can efficiently grow in these artificial systems.

Survival analysis of patients with advanced non-small cell lung cancer receiving tyrosine kinase inhibitor (TKI) treatment: A multi-center retrospective study

Background

The study was conducted to assess differences in overall survival (OS) in patients with non‐small cell lung cancer (NSCLC) receiving different treatment modalities of tyrosine kinase inhibitors (TKIs).

Methods

A total of 463 NSCLC patients receiving TKI treatment were included. OS was compared according to treatment timing in all patients, the elderly, and patients positive for EGFR mutations.

Results

One hundred and seventy two patients received TKIs as first‐line treatment, 220 as second‐line, and 67 as third‐line. The results between the three groups were not statistically significant: the one, two, and three‐year OS rates were: 55.3%, 22.3%, and 11.3% (first‐line); 59.6%, 27.8%, and 14.9% (second‐line); and 53.8%, 41.3%, and 29.5% (third‐line), respectively (P = 0.095). Results between the three groups of elderly patients were also not statistically significant (P = 0.469). The one and two‐year OS rates in EGFR mutation‐positive patients receiving first‐line treatment were 48% and 17.5%, respectively. The one, two, and three‐year OS rates of patients receiving second‐line treatment were: 54.2%, 30.3%, and 20.2%, respectively. There were no statistically significant differences between the groups with EGFR mutations receiving first‐line or second‐line treatment. Thirteen EGFR mutation‐positive patients received third‐line TKI treatment for a median duration of 7 months. Their one and two‐year OS rates were 69.8% and 58.2%, respectively, which were higher than in the other two groups (P = 0.015).

Conclusion

Three lines of TKI therapy can prolong survival in NSCLC patients. Elderly patients can benefit from TKI therapy. EGFR mutation‐positive patients can benefit from second‐line or third‐line TKI therapy.

Nonviral gene therapy in vivo with PAM-RG4/apoptin as a potential brain tumor therapeutic

Background

Glioma is still one of the most complicated forms of brain tumor to remove completely due to its location and the lack of an efficient means to specifically eliminate tumor cells. For these reasons, this study has examined the effectiveness of a nonviral gene therapy approach utilizing a tumor-selective killer gene on a brain tumor xenograft model.

Methods and results

The therapeutic apoptin gene was recombined into the JDK plasmid and delivered into human brain tumor cells (U87MG) by using a polyamidoamine dendrimer with an arginine surface (PAM-RG4). Studies in vitro showed that the PAM-RG4/apoptin plasmid polyplex exhibited a particularly high transfection activity of .40%. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, 4′,6-Diamidino-2-phenylindole (DAPI) TUNEL assay, DAPI staining, and caspase-3 activity assay verified that the tumor cells had undergone apoptosis induced by apoptin. For in vivo studies, the polyplex was injected into tumors, which were induced by injecting U87MG cells intradermally into nude mice. Based on hematoxylin and eosin staining, epidermal growth factor receptor immunohistochemistry results and tumor volume measurement results, tumor growth was effectively inhibited and no specific edema, irritation, or other harm to the skin was observed after polyplex injection. The in vivo expression of apoptin and the induction of apoptosis were verified by reverse-transcription polymerase chain reaction analysis, TUNEL assay, and DAPI staining.

Conclusion

The PAM-RG4/apoptin gene polyplex is a strong candidate for brain tumor therapeutics because of the synergistic effect of the carrier’s high transfection efficiency (35%–40%) in glioma cells and the selective apoptosis-inducing activity of apoptin in tumor cells.

Epidermal growth factor receptor as a biomarker for cervical cancer

This review focuses on the different modes of expression of the epidermal growth factor receptor (EGFR). All methods used to assess EGFR expression are critically analyzed and insights into the use of inhibitors of EGFR for treatment of cervical cancer are discussed. Currently, expression of EGFR as a biomarker for prognosis or for treatment of cervical cancer is not defined for clinical use.

Silencing kinase-interacting stathmin gene enhances erlotinib sensitivity by inhibiting Ser¹⁰ p27 phosphorylation in epidermal growth factor receptor-expressing breast cancer

The epidermal growth factor receptor (EGFR) signaling pathway has emerged as a promising target for cancer therapy. EGFR tyrosine kinase inhibitors (TKI) such as erlotinib have been approved for cancer treatment but have shown very limited activity in breast cancer patients. Clarifying the molecular mechanism underlying resistance to EGFR TKIs could lead to more effective treatment against breast cancer. We previously reported that the sensitivity of breast cancer cells to erlotinib is partially dependent on p27 and that cytoplasmic localization of p27 is associated with erlotinib resistance. In the present study, we found that erlotinib induces p27 phosphorylation at Ser¹⁰ (S10), and S10 p27 phosphorylation leads to erlotinib resistance in EGFR-expressing breast cancer. Inhibiting S10 phosphorylation of p27 by knocking down human kinase-interacting stathmin (KIS), a nuclear protein that can phosphorylate p27 at S10, led to p27 accumulation in the nucleus and enhanced erlotinib-mediated cytotoxicity. Further, in vivo KIS gene silencing enhanced the antitumor activity of erlotinib in an orthotopic breast cancer xenograft model. KIS depletion also enhanced erlotinib sensitivity in erlotinib-resistant EGFR-expressing triple-negative breast cancer cells. Our study provides a rationale for the development of combinations of erlotinib with KIS inhibition to overcome EGFR TKI resistance in EGFR-expressing breast cancer.

The distribution of the therapeutic monoclonal antibodies cetuximab and trastuzumab within solid tumors

Background

Poor distribution of some anticancer drugs in solid tumors may limit their anti-tumor activity.

Methods

Here we used immunohistochemistry to quantify the distribution of the therapeutic monoclonal antibodies cetuximab and trastuzumab in relation to blood vessels and to regions of hypoxia in human tumor xenografts. The antibodies were injected into mice implanted with human epidermoid carcinoma A431 or human breast carcinoma MDA-MB-231 transfected with ERBB2 (231-H2N) that express high levels of ErbB1 and ErbB2 respectively, or wild-type MDA-MB-231, which expresses intermediate levels of ErbB1 and low levels of ErbB2.

Results

The distribution of cetuximab in A431 xenografts and trastuzumab in 231-H2N xenografts was time and dose dependent. At early intervals after injection of 1 mg cetuximab into A431 xenografts, the concentration of cetuximab decreased with increasing distance from blood vessels, but became more uniformly distributed at later times; there remained however limited distribution and binding in hypoxic regions of tumors. Injection of lower doses of cetuximab led to heterogeneous distributions. Similar results were observed with trastuzumab in 231-H2N xenografts. In MDA-MB-231 xenografts, which express lower levels of ErbB1, homogeneity of distribution of cetuximab was achieved more rapidly.

Conclusions

Cetuximab and trastuzumab distribute slowly, but at higher doses achieve a relatively uniform distribution after about 24 hours, most likely due to their long half-lives in the circulation. There remains poor distribution within hypoxic regions of tumors.

Epidermal growth factor receptor tyrosine kinase inhibitor reverses mesenchymal to epithelial phenotype and inhibits metastasis in inflammatory breast cancer

PURPOSE

Inflammatory breast cancer (IBC) is a rare but aggressive type of advanced breast cancer. Epidermal growth factor receptor (EGFR) expression is an independent poor prognostic factor in IBC. The purpose of this study was to determine the effect on IBC tumorigenicity and metastasis of blocking the EGFR pathway.

EXPERIMENTAL DESIGN

IBC cell lines, which express high level of EGFR, were treated with EGFR small interfering RNA and with the EGFR tyrosine kinase inhibitor erlotinib. The role of EGFR in IBC cell proliferation, motility, invasiveness, and change of the expression levels of epithelial-mesenchymal transition markers was examined. The role of extracellular signal-regulated kinase (ERK)-1/2 in erlotinib activity was also studied. The activity of erlotinib in tumor growth and metastasis was examined in an orthotopic xenograft model of IBC.

RESULTS

Erlotinib inhibited proliferation and anchorage-independent growth of IBC cells, and this inhibition was ERK dependent. Erlotinib inhibited cell motility and invasiveness and reversed the mesenchymal phenotype of IBC cells to epithelial phenotype in three-dimensional culture. Erlotinib dramatically inhibited IBC tumor growth in a xenograft model. Interestingly, erlotinib inhibited spontaneous lung metastasis, even at a low dose that had no significant effect on primary tumor growth. These erlotinib-treated tumors were converted to epithelial phenotype from mesenchymal phenotype.

CONCLUSIONS

The EGFR pathway is involved in tumor growth and metastasis of IBC. Targeting EGFR through the ERK pathway may represent an effective therapeutic approach to suppress tumorigenicity and prevent metastasis in EGFR-expressing IBC.

Annulate Lamellae in a Large Cell Lung Carcinoma Cell Line with High Expression of Tyrosine Kinase Receptor and Proto-Oncogenes

The morphology, karyotype, in vitro growth properties, and expression of tyrosine kinase receptors and proto-oncogenes are reported for a newly established large cell undifferentiated lung carcinoma cell line (RVH-6849). The results were analyzed concomitantly with those for two well-established cell lines from an adenocarcinoma of the lung (A549) and a squamous cell carcinoma (A431). All three cell lines demonstrated common ultrastructural features of epithelial cells, but only RVH-6849 had frequent aggregates of centrioles and annulate lamellae (AL) and was polyploid, having five to seven copies of chromosome 7 by karyotype analysis. All three cell lines expressed transforming growth factor alpha (TGF-alpha), epidermal growth factor receptor (EGFR), c-erb B-2, and c-met genes. RVH-6849 cells, however, expressed the most messenger RNA (mRNA) for TGF-alpha, c-erb B-2, and c-met. Only EGFR mRNA was expressed more in the other two cell lines, especially in A431 cells. AL represent an exaggerated form of the nuclear membrane-pore complex that is found in actively proliferating cells such as germ and some neoplastic cells. AL are suspected to be involved in the deposition or processing of mRNA: The enhanced coexpression of AL and mRNAs of three tyrosine kinase-containing receptors in RVH-6849 cells may represent such a relationship.

Serum levels of epidermal growth factor and HER-2 neu in non small-cell lung cancer: prognostic correlation

Lung cancer is still a leading cause of cancer related mortality all over the world with the majority of cases are discovered at a late stage. Various panels of molecular prognostic markers are being studied to map the association of these markers with response and survival. The aim of this study is to study levels of epidermal growth factor receptor (EGFR), HER-2 neu in both serum and bronchoalveolar lavage (BAL) in patients with non small-cell lung cancer (NSCLC), correlate their levels with clinical, pathological characters as well as prognosis. A total of 30 patients with pathologically proven NSCLC were enrolled in this study in addition to ten normal controls subjects and ten cases with benign pulmonary diseases as broncheicatsis, chronic obstructive pulmonary disease. Results revealed significantly increased levels of EGFR and HER-2 neu in both serum and bronco-alveolar lavage compared with controls. The levels were significantly higher in those with stages III, IV compared with I, II, and in those with higher grades of the tumor. There was no statistically significant correlation with performance status or survival. In conclusion, serum measurement of these markers is a promising noninvasive technique which needs correlation with other methods of determination, measurement at different chronological points during disease evolution to explore its full potential. Standardization of techniques for determination of EGFR and HER-2 neu over-expression must become a priority in future studies that should also include larger number of patients, conducted in a prospective manner together with comparisons of various methods and correlation of protein expression with gene copy numbers.

T helper type 1 cytokines and keratinocyte growth factor play a critical role in pseudoepitheliomatous hyperplasia initiation during cutaneous leishmaniasis

Pseudoepitheliomatous hyperplasia (PEH) is an exuberant proliferation of the epidermis. The underlying mechanism(s) that lead to PEH have not been completely elucidated. Here, we characterize PEH during the healing stages of cutaneous leishmanial ulcers in mice. During experimental cutaneous leishmaniasis (CL) C57BL/6 mice produce PEH, and BALB/c do not. A series of immunohistochemical and immunological studies were performed to identify the secretory products of PEH regulation. We observed that the distribution of TNF-alpha and IFN-gamma under PEH had a stripe-like diffuse pattern and localized in the upper part of the papillary dermis directly under the proliferating epidermis. Macrophages were identified as the major source of TNF-alpha (56.3%). The importance of IFN-gamma and TNF-alpha in PEH development was proven by the initiation of PEH after three intralesional injections of TNF-alpha and IFN-gamma every three days in infected BALB/c mice. In C57BL/6 mice, keratinocyte growth factor (KGF) expressing cells were found immediately under the basal membrane of the hyperplastic epidermis in comparison with sporadic KGF positive cells deep in the dermis of BALB/c mice. Quantitative RT-PCR analysis demonstrated increased KGF and KGF receptor expression in uninfected C57BL/6 mice as compared to BALB/c mice. These data indicate that Th1 cytokines and KGF play a critical role in PEH initiation during CL.

Expression of epidermal growth factor receptor in squamous cell carcinomas of the anal canal is independent of gene amplification

Immunohistochemical detection of expression of the epidermal growth factor receptor (EGFR) has been utilized to identify eligible patients with solid malignant tumors, including colorectal adenocarcinoma, for monoclonal antibody therapy (eg, cetuximab). The EGFR status in squamous cell carcinoma of the anal canal, an uncommon malignancy traditionally treated with chemoradiation, has not been well investigated. In this study, 38 primary squamous cell carcinomas of the anal canal were immunohistochemically examined for EGFR expression and analyzed by fluorescence in situ hybridization (FISH) for EGFR gene copy numbers. The results showed a variable degree of EGFR expression in 21 (55%) tumors, among which 13 (62%) cases exhibited a 2+ to 3+ staining pattern according to the Dako EGFR phamDx interpretation guide. There were no significant differences among tumors stratified by stage, degree of keratinization, or tissue block storage times. FISH analysis showed that none of the 34 cases with interpretable results had EGFR gene amplification. Increased gene copy numbers due to polysomy 7 were seen in seven of 18 (39%) cases that expressed EGFR protein and four of 16 (25%) cases that did not (P=0.3876). Ten (56%) tumors with positive EGFR staining showed a balanced disomy 7 pattern and one case with monosomy 7 exhibited strong EGFR expression (3+). These results demonstrate that EGFR is overexpressed in more than one-half of the squamous cell carcinomas of the anal canal through mechanisms other than gene amplification. These observations may have important therapeutic implications since EGFR-based targeted therapies have shown promise for other malignant neoplasms.

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.

Epidermal growth factor receptor in non-small-cell lung carcinomas: correlation between gene copy number and protein expression and impact on prognosis

PURPOSE

The epidermal growth factor receptor (EGFR) is frequently overexpressed in non-small-cell lung carcinoma (NSCLC), and EGFR inhibitors are promising new therapeutic agents. The molecular mechanisms responsible for EGFR overexpression are poorly understood.

MATERIALS AND METHODS

Gene copy number and protein status of EGFR were investigated in microarrayed tumors from 183 NSCLC patients, including squamous cell carcinoma (SCC; 89 patients) and non-SCC (94 patients) histologies. Protein expression was assessed by immunohistochemistry on a scale from 0 to 400 (percentage of positive cells x staining intensity). Gene and chromosome 7 copy numbers were identified by fluorescent in situ hybridization (FISH).

RESULTS

EGFR protein overexpression was observed in 62% of the NSCLC (25% scored 201 to 300; 37% scored 301 to 400), more frequently in SCC than non-SCC (82% v 44%; P <.001), and in 80% of the bronchioloalveolar carcinomas. The prevalent FISH patterns were balanced disomy (40%) and trisomy (38%) for EGFR gene and chromosome 7 (40%), whereas balanced polysomy was seen in 13% and gene amplification was seen in 9% of the patients. Gene copy number correlated with protein expression (r = 0.4; P <.001). EGFR overexpression or high gene copy numbers had no significant influence on prognosis.

CONCLUSION

EGFR overexpression is frequent in NSCLC, is most prominent in SCC, and correlates with increased gene copy number per cell. High gene copy numbers per cell showed a trend toward poor prognosis. It will be important to evaluate EGFR gene and EGFR protein status and signal protein expression to properly interpret future clinical trials using EGFR inhibitors.

Immunogene therapy of tumors with vaccine based on xenogeneic epidermal growth factor receptor

The breaking of immune tolerance against self epidermal growth factor receptor (EGFr) should be a useful approach for the treatment of receptor-positive tumors with active immunization. To test this concept, we constructed a plasmid DNA encoding extracellular domain of xenogeneic (human) EGFr (hEe-p) or corresponding control mouse EGFr (mEe-p) and empty vector (c-p). Mice immunized with hEe-p showed both protective and therapeutic antitumor activity against EGFr-positive tumor. Sera isolated from the hEe-p-immunized mice exhibited positive staining for EGFr-positive tumor cells in flow cytometric analysis and recognized a single 170-kDa band in Western blot analysis. Ig subclasses responded to rEGFr proteins were elevated in IgG1, Ig2a, and Ig2b. There was the deposition of IgG on the tumor cells. Adoptive transfer of the purified Igs showed the antitumor activity. The increased killing activity of CTL against EGFr-positive tumor cells could be blocked by anti-CD8 or anti-MHC class I mAb. In vivo depletion of CD4(+) T lymphocytes could completely abrogate the antitumor activity, whereas the depletion of CD8(+) cells showed partial abrogation. The adoptive transfer of CD4-depleted (CD8(+)) or CD8-depleted (CD4(+)) T lymphocytes isolated from mice immunized with hEe-p vaccine showed the antitumor activity. In addition, the increase in level of both IFN-gamma and IL-4 was found. Taken together, these findings may provide a new vaccine strategy for the treatment of EGFr-positive tumors through the induction of the autoimmune response against EGFr in a cross-reaction between the xenogeneic homologous and self EGFr.

Lung cancer. 1: prevention of lung cancer

Cancer of the lung causes more deaths from cancer worldwide than at any other site. The environmental, genetic, and dietary risk factors are discussed and progress in chemoprevention is reviewed. A better understanding of the molecular events that occur during carcinogenesis has opened up new areas of research in cancer prevention and a number of biochemical markers of high risk individuals have been identified. It is predicted that greater success in chemoprevention will be achieved in the next decade than in the last.

ZD1839, a selective epidermal growth factor receptor tyrosine kinase inhibitor, alone and in combination with radiation and chemotherapy as a new therapeutic strategy in non-small cell lung cancer

The epidermal growth factor receptor is overexpressed in a majority of non-small cell lung cancers and has been associated with a poor prognosis. Preclinical studies have shown that ZD1839, an oral anilinoquinazoline, targets the epidermal growth factor receptor-associated tyrosine kinase, reversibly inhibiting critical downstream signaling and resulting in cancer cell growth arrest. Potent antitumor effects have been observed in human lung tumor xenograft models. Preclinical studies have shown additive to synergistic effects when ZD1839 is combined with radiation or chemotherapy in colon, head and neck, and non-small cell lung cancers. Phase I clinical trials have shown modest dose-related toxicity, and antitumor activity has been reported in a variety of malignancies including lung cancer. Future studies will certainly combine ZD1839 with chemotherapy or radiation. ZD1839 also may be effective as a chemoprevention agent because premalignant lesions often overexpress epidermal growth factor receptor.

Epidermal growth factor receptor family in lung cancer and premalignancy

Lung cancer, like many other epithelial malignancies, is thought to be the outcome of genetic and epigenetic changes that result in a constellation of phenotypic abnormalities in bronchial epithelium. These include morphologic epithelial dysplasia, angiogenesis, increased proliferative rate, and changes in expression of cell surface proteins, particularly overexpression of epidermal growth factor receptor (EGFR) family proteins. The EFGR family is a group of four structurally similar tyrosine kinases (EGFR, HER2/neu, ErbB-3, and ErbB-4) that dimerize on binding with a number of ligands, including EGF and transforming growth factor alpha. Epidermal growth factor receptor overexpression is pronounced in virtually all squamous carcinomas and is also found in > or = 65% of large cell and adenocarcinomas. It is not expressed in situ by small cell lung carcinoma. Overexpression of EGFR is one of the earliest and most consistent abnormalities in bronchial epithelium of high-risk smokers. It is present at the stage of basal cell hyperplasia and persists through squamous metaplasia, dysplasia, and carcinoma in situ. Recent studies of the effect of inhibitors of receptor tyrosine kinases suggest that patterns of coexpression of multiple members of the EGFR family could be important in determining response. Intermediate endpoints of such trials could include monitoring of phosphorylation levels in signal transduction molecules downstream of the receptor dimers. These trials represent a new targeted approach to lung cancer treatment and chemoprevention that will require greater attention to molecular endpoints than required in past trials.

Anti-CD3/anti-epidermal growth factor receptor-bispecific antibody retargeting of lymphocytes against human neoplastic keratinocytes in an autologous organotypic culture model

Local cellular immune defects have been described in several tumors including human papillomavirus (HPV)-associated cervical cancer. This observation suggests the potential therapeutic benefit of immune manipulations that restore cellular immunity. Here, we evaluated the ability of bispecific monoclonal antibodies (bimAbs) to redirect T cells against keratinocytes transformed in vitro by HPV in an autologous three-dimensional culture model (organotypic cultures). The epidermal growth factor receptor (EGFR) was chosen as target for an anti-CD3/anti-EGFR bimAb because it is overexpressed in many malignant epithelial lesions and only weakly expressed in the basal layers of normal squamous epithelium. Interestingly, in organotypic cultures, the pattern of expression of EGFR was similar to that observed in vivo. The ability of T cells retargeted by CD3/EGFR bimAb to lyse HPV-transformed cell lines was confirmed in monolayer cultures. In autologous organotypic cultures, an increase in apoptotic HPV(+) keratinocytes and a significant decrease in the thickness of HPV(+) organotypic cultures were observed when activated lymphocytes and bimAbs were added to the cultures, whereas organotypic cultures of normal keratinocytes were not significantly affected. These data were similar to those obtained in the allogeneic model. These results suggest the potential usefulness of CD3-EGFR bimAb-retargeted lymphocytes in immunotherapeutic protocols for malignant epithelial lesions.

Molecular abnormalities in lung carcinogenesis and their potential clinical implications

Development of lung cancer is multistep and requires accumulation of multiple genetic and epigenetic alterations. Modern molecular technology has facilitated a rapid and effective identification of these genetic alterations as well as epigenetic alterations. The determination of molecular alterations in the early tumorigenic process of the lung will not only extend our understanding of the underlying biology but also provide molecular markers for cancer risk assessment, early detection, and molecular classification. In this article, I will discuss the common molecular abnormalities in lung cancer and how these abnormalities may be used as biomarkers in clinical practice.

Pseudocarcinomatous change in lymphomatoid papulosis and primary cutaneous CD30+ lymphoma: a clinicopathologic and immunohistochemical study of 6 patients

We report 6 cases of pseudoepitheliomatous hyperplasia (PEH) mimicking squamous cell carcinoma in association with an atypical CD30+ dermal infiltrate. Three patients had lymphomatoid papulosis type A, and 3 patients had cutaneous CD30+ lymphoma. All 6 cases showed histologic evidence of PEH with keratinocyte atypia. In 4 cases there was significant atypia to prompt a diagnosis of squamous cell carcinoma. Three of these received treatment with wide local excision and 2 had been engrafted. Immunohistochemical staining for epidermal growth factor (EGF) and transforming growth factor alpha (TGF-alpha) showed similar expression in lesional and perilesional skin. Epidermal growth factor receptor (EGFR) expression by the proliferating epithelium was similar to that of the suprabasal adjacent normal epidermis. There was no aberrant expression of EGF, TGF-alpha, and EGFR by atypical lymphocytes. These cases demonstrate that PEH associated with CD30+ lymphoproliferative disease may closely resemble squamous cell carcinoma, thereby leading to inappropriate diagnosis and treatment.

Inhibitors of protein tyrosine phosphorylation: preliminary assessment of activity by time-resolved fluorescence

Epidermal growth factor (EGF) receptor (ErbB1)-associated tyrosine kinase inhibitors may act as potential chemotherapeutic agents. In order to assess the inhibitory activity of these compounds, we developed a simple and sensitive assay based on time-resolved fluorescence. In this technique, crude cell lysates bearing the ErbB1 receptor were captured in microtitre plates immobilized with monoclonal anti-ErbB1 antibody SG 565. Subsequently, the phosphotyrosine content of the cell lysates was quantified by a europium-labelled anti-phosphotyrosine antibody. Thus, genistein, a tyrosine kinase inhibitor, was capable of reducing by half the tyrosine phosphorylation caused by the binding of EGF to A431 cells, whereas 6-carboxymethyl genistein did not inhibit protein tyrosine phosphorylation. This assay is simple to perform, does not use radioactive substrates, and can be useful for screening EGF receptor tyrosine kinase inhibitors from natural products or synthetic compounds. Moreover, the assay has a high signal:noise ratio and is suitable for large-scale screening.

Co-expression of epidermal growth factor receptor and transforming growth factor-alpha is independent of ras mutations in lung adenocarcinoma

The interaction of epidermal growth factor receptor (EGFR) and its ligand transforming growth factor-alpha (TGF-alpha) leads to an autocrine activation of the ras signaling pathway and putatively its oncogenic activity. It is thus hypothesized that the co-overexpression of EGFR-TGFalpha will be redundant hence rare in tumors with oncogenic ras mutations. To test this hypothesis, we studied by immunohistochemistry the expression of EGFR and TGF-alpha in primary non small cell lung cancers. Such putative EGFR autocrine loop activation was found in 73% of squamous cell carcinomas that rarely develop ras mutations. In contrast, EGFR-TGFalpha co-expression occurred with equal frequency in adenocarcinomas irrespective of their ras genotype. The results indicate that EGFR autocrine loop activity in adenocarcinoma may have alternative signaling activities aside from the activation of ras-MAP kinase pathway.

Molecular biology of pancreatic cancer; oncogenes, tumour suppressor genes, growth factors, and their receptors from a clinical perspective

Pancreatic cancer represents the fourth leading cause of cancer death in men and the fifth in women. Prognosis remains dismal, mainly because the diagnosis is made late in the clinical course of the disease. The need to improve the diagnosis, detection, and treatment of pancreatic cancer is great. It is in this type of cancer, in which the mortality is so great and the clinical detection so difficult that the recent advances of molecular biology may have a significant impact. Genetic alterations can be detected at different levels. These alterations include oncogene mutations (most commonly, K-ras mutations, which occur in 75% to more than 95% of pancreatic cancer tissues), tumour suppressor genes alterations (mainly, p53, p16, DCC, etc.), overexpression of growth factors (such as EGF, TGF alpha, TGF beta 1-3, aFGF, bTGF, etc.) and their receptors (i.e., EGF receptor, TGF beta receptor I-III, etc.). Insights into the molecular genetics of pancreatic carcinogenesis are beginning to form a genetic model for pancreatic cancer and its precursors. These improvements in our understanding of the molecular biology of pancreatic cancer are not simply of research interest, but may have clinical implications, such as risk assessment, early diagnosis, treatment, and prognosis evaluation.

Pseudoepitheliomatous hyperplasia in cutaneous T-cell lymphoma. A clinical, histopathological and immunohistochemical study with particular interest in epithelial growth factor expression. The French Study Group on Cutaneous Lymphoma

Pseudoepitheliomatous hyperplasia has occasionally been reported in cutaneous T-cell lymphoma (CTCL). This association raises the question of the relationship between epidermal hyperplasia and the lymphomatous infiltrate. Because epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) have been demonstrated to be involved in epidermal proliferation through binding to EGF receptor (EGFr), we tested the hypothesis that these cytokines could be secreted by lymphomatous cells, and induce the overlying pseudoepitheliomatous hyperplasia. The purposes of this study were: (i) to describe the clinical and immunohistological features of pseudoepitheliomatous hyperplasia; (ii) to determine its frequency in a large series of CTCLs; and (iii) to evaluate the expression of EGF, TGF-alpha and EGFr in CTCL with or without pseudoepitheliomatous hyperplasia. Eleven cases of CTCL with pseudoepitheliomatous hyperplasia were collected from a series of 353 cases of cutaneous lymphoma registered from 1990 to 1996. They consisted of eight of 28 (28.5%) CD30+ large T-cell lymphomas and three of 148 (2%) cases of mycosis fungoides. Epidermal expression of EGF, EGFr and TGF-alpha was stronger in CTCL than in control normal human skin. Lymphomatous T cells expressed EGF and TGF-alpha whereas no expression of these cytokines could be detected in cutaneous and nodal B-cell lymphomas, nor in a normal lymph node. In addition, epidermal expression of EGFr was stronger in CTCL with pseudoepitheliomatous hyperplasia than in control cases of CTCL without pseudoepitheliomatous hyperplasia, suggesting that these cytokines, in association with other factors, are probably involved in the epidermal hyperplasia observed in some cases of CTCL.

Enzyme-linked immunosorbent assay of epidermal growth factor receptor in lung cancer: comparisons with immunohistochemistry, clinicopathological features and prognosis

The prognostic role of epidermal growth factor receptor (EGFR) remains controversial in patients with lung cancer. Previous assays for EGFR have primarily been qualitative or, at best, semiquantitative. In the present study, using fresh-frozen tissue from 190 unselected lung cancer patients, quantification of EGFR (EGFR(ELISA)) using a recently developed enzyme-linked immunosorbent assay (ELISA) technique was compared with results (EGFR(IHC)) obtained using immunohistochemistry (IHC). Correlation between results obtained by the two different techniques was highly significant (r(s) = 0.63, P < 0.001, n = 190). This correlation improved even further (r(s) = 0.76) when sections were estimated using an IHC score that took into account percentage staining, intensity and relative tumour area. Furthermore, the relationship between clinicopathological features and prognosis was identical for the two methods. The expression of EGFR was highest in squamous cell carcinomas, but it was not correlated with other characteristics such as age, sex, histological grading, stage or prognosis. We conclude that evaluation of EGFR content using IHC and ELISA produces comparable results.

Bispecific antibodies for treatment of cancer in experimental animal models and man

Immunotherapy is a powerful anti-cancer treatment modality. However, despite numerous encouraging results obtained in pre-clinical studies, a definite breakthrough towards an established clinical treatment modality has as yet not occurred. Antibodies against tumor antigens have been shown to localise at the site of the tumor, but inadequate triggering of immune effector mechanisms have thwarted clinical efficacy thus far. Cellular immunotherapy has been hampered by limitations such as lack of specificity, down-regulation of major histocompatibility complex (MHC)-expression or Fas ligand up-regulation on tumor cells. This review focuses on the use of bispecific antibodies (BsAbs) for immunotherapy of cancer. Using BsAbs, it is possible to take advantage of the highly specific binding characteristics of antibodies and combine these with the powerful effector functions of cytotoxic immune effector cells. BsAbs share two different, monoclonal antibody-derived, antigen-recognizing moieties within one molecule. By dual binding, BsAbs reactive with a trigger molecule on an immune effector cell on the one hand and a surface antigen on a tumor target cell on the other are thus able to functionally focus the lytic activity of the immune effector cell towards the target cell. Over the last few years, the concept of BsAb-mediated tumor cell killing has been studied extensively both in preclinical models and in a number of phase I clinical trials. Promising pre-clinical results have been reported using tumor models in which diverse immune effector cell populations have been used. Despite this pre-clinical in vivo efficacy, the first clinical trials indicate that we are still not in a position to successfully treat human malignancies. This review discusses the production of BsAbs, the choice of trigger molecules in combination with potential effector cells and the preclinical models that have led to the current use of BsAbs in experimental clinical trials. It has become clear that appropriate immune cell activation and establishing a favourable effector-to-target cell ratio will have direct impact on the efficacy of the therapeutic approaches using BsAbs. New directions are discussed, i.e. finding appropriate dosage schemes by which immune effector cells become redirected without inducing hyporesponsiveness, defining possibilities for combining different immune effector cell populations and creating an in situ tumor environment that allows maximal tumoricidal activity

Combined chromosome microdissection and comparative genomic hybridization detect multiple sites of amplification DNA in a human lung carcinoma cell line

Chromosome microdissection-fluorescence in situ hybridization and comparative genomic hybridization (CGH) were performed in parallel to identify the native location of amplified DNA in a human non-small cell lung cancer (NSCLC) cell line exhibiting a homogeneously staining region (hsr) and double minutes (dmin). The native locations of microdissected DNA from the hsr and dmin were 7p12-13 and 8q24, respectively. Southern analysis revealed coamplification of EGFR (7p12) and MYC (8q24). CGH detected amplification of DNA not only from 7p12-13 and 8q24, but also from 9p24 and 10q22.

Genetic factors in lung disease. Part II: Lung cancer and angiotensin converting enzyme gene

The recent progress in molecular biology has led to the elucidation of pathogenesis of lung cancer. The development of a lung cancer requires multiple genetic changes, consisting of the activation of oncogenes, including the K-ras and myc genes, and of inactivation of tumour suppressor genes, including the Rb, p53 and CDKN2 genes. Knowing the specific genes undergoing such changes should be useful as biomarkers for the early detection of cells destined to become malignant. Moreover, such genetic changes could be targets of newly designed drugs and gene-based therapy. Although the angiotensin I-converting enzyme was originally discovered in equine plasma, it has been recognized in various organs and cells other than vascular endothelial cells. This enzyme is also known to have wide substrate specificity to many peptides. The definite roles of angiotensin converting enzyme (ACE) in the respiratory system are largely unknown. Recent progress in molecular biology of the ACE, however, gives us a good chance to look over the significance of ACE in respiratory diseases as well as cardiovascular disorders. In this review, we show the recent advances in the basic studies of the ACE and refer to its clinical application.

Clinical relevance of transforming growth factor-beta 1 in the urine of patients with hepatocellular carcinoma

To assess the clinical relevance of transforming growth factor-beta 1 (TGF-beta 1) in the urine of patients with hepatocellular carcinoma (HCC), TGF-beta 1 was measured, by radioimmunoassay, in 140 patients with HCC, 50 cirrhotic patients, 30 patients with chronic active hepatitis, and 50 healthy controls. The results indicate that there were significantly increased urinary TGF-beta 1 levels in patients with HCC. Raised TGF-beta 1 levels were associated, in a dose-related fashion, with increased risk for development of HCC (odds ratio, 1.05, 95% confidence interval, 1.03-1.07). HCC patients with raised TGF-beta 1 levels had shorter survival than those with normal TGF-beta 1 levels (p = 0.038). TGF-beta 1 levels decreased after successful anticancer therapy (p < 0.0001). There was an inverse correlation between TGF-beta 1 and serum alpha-fetoprotein (AFP) (r = -0.199, p < 0.04). Receiver operating characteristics (ROC) curve analysis indicated that parallel determination of TGF-beta 1 and AFP significantly increased the sensitivity and diagnostic accuracy, with a high specificity. In conclusion, raised urinary TGF-beta 1 was associated with HCC development. It is a predictor of poor prognosis, and a tumor marker for diagnosis and therapeutic follow-up of HCC.

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

Epidermal growth factor receptor (EGFR) was measured using a competitive radioligand binding assay in membrane preparations from 74 primary human non-small cell lung cancer (NSCLC) tissues and 20 pathologically normal peripheral lung tissues. The mean EGFR level in tumours was 30.38 fmol/mg (+/-41.95 S.D.) of membrane protein (mg.p), significantly higher (P = 0.00016) than in normal tissues (mean, 10.26 +/- 10.02 fmol/mg.p). The mean EGFR concentration was also significantly higher in pathological stage IV tissue than in stages I (P = 0.049) and II (P = 0.040), and the mean EGFR concentration was significantly higher in cases with mediastinal involvement than in cases without it (P = 0.029). The mean EGFR level was higher in DNA aneuploid and multiploid cases than in DNA diploid cases, but there was no significant difference. No significant relationships were found to exist between receptor concentrations and pathological tumour size or histological type, or patient gender or age. From the above findings, a possible prognostic role for EGFR in primary NSCLC should be investigated.

Tyrosine phosphorylation of 100-130 kDa proteins in lung cancer correlates with poor prognosis

To search for the signalling pathways in lung cancer relevant to its aggressive behaviour, we studied tyrosine phosphorylated proteins in lung cancer cell lines and surgical specimens. We found that the profiles of protein phosphorylation were closely matched among these cell lines and cancer tissues of different histological origins, and 100-130 kDa proteins were the major components of phosphorylated proteins. In surgical specimens, approximately half of the cases showed tyrosine phosphorylation of these proteins in a tumour-specific manner, and phosphorylation of these proteins showed good correlation with the survival length of patients after operation. By immunoprecipitation with specific antibodies, we found that p125FAK, p120 and beta-catenin were the major components of tyrosine-phosphorylated proteins in the surgical specimens. These results suggest that tyrosine phosphorylation of these proteins may play a role in tumour relapse and is available as a clinical marker.

The epidermal growth factor receptor and its ligands as therapeutic targets in human tumors

The epidermal growth factor receptor (EGFR) is detected on many non-haematopoietic tissues and is frequently overexpressed in human tumors. With its ligand, TGF-alpha, it forms a well-defined autocrine growth loop. Several clinical approaches, using EGFR as a therapeutic target, are being investigated, particularly monoclonal antibodies combined with chemotherapy, and pharmacological inhibition of downstream components of the EGFR signaling pathway.

Lack of prognostic significance of epidermal growth factor receptor and the oncoprotein p185HER-2 in patients with systemically untreated non-small-cell lung cancer: an immunohistochemical study on cryosections

The prognostic role of the epidermal growth factor receptor (EGFR) and the related receptor p185HER-2 in lung cancer is as yet undefined. We investigated the immunohistochemical expression of EGFR (monoclonal antibody R1; Amersham) and p185HER-2 (polyclonal antibody A485; Dako) in cryosections. A total of 186 unselected and systemically untreated patients with non-small-cell lung cancer (NSCLC) diagnosed and treated at Odense University Hospital, Denmark, were included. Median follow-up period was 66 months. EGFR and p185HER-2 was highly expressed in 55% and 26% of cases respectively. Expression of EGFR was independent of p185HER-2 expression. The expression of EGFR was higher in squamous cell carcinomas whereas the level of p185HER-2 staining was higher in adenocarcinomas. Expression of either or both receptors was not correlated with age, histological grading, stage and prognosis. We conclude that immunohistochemical detection of these growth factor receptors failed to demonstrate a prognostic significance in patients operated on for NSCLC.

Ligand-independent dimerization of oncogenic v-erbB products involves covalent interactions

Mutant v-erbB products of avian c-erbB1 have previously been used to correlate structural domains of the receptor encoded by this proto-oncogene with tissue-specific transformation potential. In these studies, deletion of the ligand-binding domain of the receptor has been shown to be required for transformation of erythroblasts, fibroblasts, and endothelial cells. It has, therefore, been postulated that deletion of this domain results in an allosteric change in the receptor analogous to the ligand-bound state of the epidermal growth factor receptor; i.e., it induces a receptor conformation that is constitutively active with respect to mitogenic signaling. While oncogenic v-erbB products have been shown to be expressed on the cell surface of both fibroblasts and erythroblasts, no comprehensive analysis of the oligomeric potential of these products has been conducted. Since the first event known to follow epidermal growth factor binding to its receptor is oligomerization, and receptor dimerization has been correlated with mitogenic signaling, we have carefully analyzed the ability of several v-erbB products to oligomerize in the three target cell types transformed by these oncogenes. In this report, we demonstrate the v-erbB products can efficiently homodimerize in all three target tissues, that this dimerization is ligand independent and occurs at the cell surface, and that there is no apparent correlation between v-erbB dimerization and transformation of avian fibroblasts. Furthermore, both oncogenic and nononcogenic v-erbB products can heterodimerize with the native c-erbB1 product in chicken embryo fibroblasts, suggesting that heterodimerization between v-erB and native c-erbB1 is not sufficient to result in c-erbB1-mediated sarcomagenesis.

Overexpression of different members of the type 1 growth factor receptor family and their association with cell proliferation in periampullary carcinoma

The expression of epidermal growth factor receptor (EGFR), c-erbB-2, and c-erbB-3 was examined immunohistochemically in 57 cases of periampullary carcinoma. The percentage of Ki-67-positive cells was also examined in the same tissue, to determine the relationship between the expression of the members of the type I growth factor receptor family and cell proliferation. In carcinoma of the head of pancreas, the percentage of cases with overexpression of c-erbB-3 was significantly higher than with overexpression of c-erbB-2 and EGFR. In contrast, in lower bile duct carcinoma and carcinoma of the ampulla of Vater, the percentages of cases with overexpression of c-erbB-2 was greater than with overexpression of other growth factor receptors. A higher percentage of cases with overexpression of c-erbB-3 in pancreatic head carcinoma and overexpression of c-erbB-2 in carcinoma of the ampulla of Vater was found in Ki-67 antigen-positive cases. Moreover, the overexpression of c-erb-3 in pancreatic head carcinoma, c-erb-2 in ampulla of Vater carcinoma, and Ki-67 in both carcinomas was found to be associated with poor patient outcome. These results demonstrate that different members of the type I growth factor receptor family are overexpressed in different carcinomas of the periampullary region.

Peptides and growth factors in non-small cell lung cancer

Numerous growth factors and receptors that alter proliferation have been identified in lung cancer. In non-small cell lung cancer (NSCLC) cell lines, high levels of vasoactive intestinal peptide (VIP) mRNA have been detected by Northern analysis, and immunoreactive VIP is present. VIP elevates intracellular cAMP and stimulates the clonal growth of NSCLC cells. Also, transforming growth factor alpha (TGF-alpha) mRNA is present in NSCLC cells and TGF-alpha is present in conditioned media exposed to NSCLC cells. TGF-alpha binds with high affinity to epidermal growth factor (EGF) receptors present on NSCLC cells. EGF stimulates tyrosine kinase activity and growth in NSCLC cells. Synthetic peptide antagonists and monoclonal antibodies have been identified that disrupt autocrine growth pathways and inhibit NSCLC growth. These data suggest that VIP and TGF-alpha are important autocrine growth factors for NSCLC.

Immunohistochemical localization of epidermal growth factor receptor and epithelial antigen in tumors of the human conjunctiva, eyelid, lacrimal gland, and orbit

BACKGROUND

Increased numbers of epidermal growth factor (EGF) receptors are observed in squamous cell carcinomas of human lung, head, neck, and cervix. We studied the presence of EGF receptors and epithelial antigen in some ophthalmic lesions.

METHODS

Immunohistochemical staining for EGF receptors was assessed in tumors of human conjunctiva, eyelid, lacrimal glands, and orbit with monoclonal antibodies (EGF-R1 and clone 29.1). Reactivity of Ber-EP4, which recognizes epithelial antigen, was also examined.

RESULTS

Strong staining of EGF-R1 and clone 29.1 and weak to moderate staining of Ber-EP4 were demonstrated in conjunctival squamous cell carcinomas. Cell membranes of conjunctival papilloma were moderately or strongly stained with these antibodies. Ductal components in sebaceous gland adenoma of the eyelid and pleomorphic adenoma of the lacrimal gland were positively stained. The antibodies did not bind to reactive lymphoid hyperplasia of the orbit and Wegener's granulomatosis. Relatively good correlation for immunostaining reaction was observed among EGF-R1, clone 29.1, and Ber-EP4 in each tumor.

CONCLUSION

Immunostaining using EGF-R1, clone 29.1, and Ber-EP4 may be useful in differentiating epithelial tumors from non-epithelial lesions. Strong immunostaining for EGF receptor may be the hallmark of epidermoid malignancy.

Expression of epidermal growth factor receptor messenger RNA in human colorectal carcinomas assessed by non-radioactive in-situ hybridization

No consensus as to the involvement of the epidermal growth factor receptor (EGF-R) in colorectal carcinomas has yet been attained, although they are assumed to play a role in the metastasis to lymph nodes and recurrence of breast carcinoma and bladder carcinoma invasion. Knowing that Dukes' classification of colorectal carcinoma is closely related to prognosis, we examined whether there is a correlation between Dukes' classification and the expression of EGF-R in colorectal carcinoma. If there is a positive correlation, the involvement of EGF-R in the processes may be assumed and the expression of EGF-R may be used as a marker of their prognosis. To this end, the expression of EGF-R mRNA and protein by non-radioactive in-situ hybridization and immunohistochemistry, respectively, were determined on histological preparations of formalin-fixed paraffin-embedded colorectal surgical specimens. In 30 cases of colorectal carcinoma examined, mRNA and/or protein was detected in 33% (two of six) of Dukes' A, in 40% (four of 10) of Dukes' B, in 36% (four of 11) of Dukes' C, in 33% (one of three) of Dukes' D and in 0% of normal colon epithelial cells. Thus, there was no positive correlation between the Dukes' classification and the expression of EGF-R. It is concluded that the expression of EGF-R in colorectal carcinoma is not a promising marker of prognosis. However, the role of EGF-R in EGF-R positive tumours remains to be examined.

Divergent effects of epidermal growth factor and calcipotriol on human rectal cell proliferation

Vitamin D may protect against colorectal cancer by reducing cell proliferation and inducing differentiation. By contrast, epidermal growth factor (EGF) stimulates cell proliferation and may encourage gastrointestinal mucosal healing. This study investigated the effect of a synthetic vitamin D analogue, calcipotriol, and EGF on human rectal epithelial cell proliferation in patients with familial adenomatous polyposis (FAP). In addition, a new technique to measure the cell cycle time is described. Sigmoidoscopic biopsy specimens were obtained from 14 patients with FAP. Tissue was established in organ culture, with or without the addition of EGF (n = 8), or calcipotriol (n = 6). Proliferation was determined using (a) metaphase arrest to measure the crypt cell production rate, (b) native mitotic index, and (c) the growth fraction using PC10 antibody. EGF receptor expression was shown using a polyclonal antibody AP12E. Calcipotriol reduced crypt cell production rate by 52% from mean (SEM) 5.29 (1.18) to 2.56 (0.80) cells/crypt/hour (p < 0.01) and EGF increased crypt cell production rate by 102% from 3.62 (0.59) to 7.33 (0.90) cells/crypt/hour (p < 0.05), and this tissue expressed the EGF receptor. The growth fraction was 48.40 (4.0)%, and the native mitotic index 1.08 (0.14)%. The cell cycle time was estimated as 94.5 hours and the time for mitosis as one hour. Thus, calcipotriol and EGF have divergent effects on human rectal mucosal proliferation.

[Epidermal growth factor receptor in non-small cell cancer of the lung]

In this study we determined the concentration of epidermic growth factor receptors (EGFr) in non-small cell carcinoma of the lung (NSCCL) and analyzed its relation to the anatomical, pathological and clinical factors of these neoplasms. The concentration of EGFr in 62 tumor tissue samples was 9.9 +/- 14 fmol/mg, higher than that found in 14 tissue samples from cases of spontaneous pneumothorax (3.9 +/- 3.6 fmol/mg) (p = 0.005). EGFr concentration in lung tissue with no signs of neoplasm was 6.5 +/- 10 fmol/mg. In 21 (33%) cases of NSCCL the concentration exceeded the normal threshold of 10 fmol/mg. EGFr concentration was higher in cases of epidermoid carcinoma than in other tissue samples (p = 0.042). No significant association was found between EGFr levels and status of tumor node metastasis, degree of differentiation and mitotic index. The probability of remaining free of tumor recurrence and of survival after 24 months among patients whose tumoral EGFr concentration was below 10 fmol/mg was 34 and 40%, respectively. The rates for patients with concentrations that exceeded the threshold were 20% (p = 0.32) and 25% (p = 0.26), respectively. The results seem to indicate that the study of EGFr concentration alone does not yield practically important information for the management of patients with NSCCL who have undergone surgery. The concentration of EGFr marks degree of differentiation in NSCCL and has prognostic implications derived from its association with other factors.