Interleukin-4 receptor and epidermal growth factor receptor expression in colorectal cancer.

Interleukin-4 receptor (IL-4R) and Epidermal Growth Factor receptor (EGFR) were assessed as factors associated with adenoma-carcinoma progression in colorectal cancer and tumour invasion. A monoclonal antibody (MR6) was applied to detect IL-4R in: metaplastic polyps (five cases), adenomas (15 cases), and carcinomas (44 adenocarcinomas and one squamous cell). Positive labelling was obtained in all polyps, adenomas and in 40/45 carcinomas. Normal colonic mucosa of these patients, as well as macrophages and lymphocytes infiltrating the tumour stroma, were also positively labelled with MR6. Four out of five poorly differentiated adenocarcinomas did not show IL-4 receptor expression. No significant correlation was found with tumour size, lymph node stage and IL-4 receptor expression. On the above specimens a parallel detection of epidermal growth factor receptors (EGFR) by a monoclonal antibody (EGFR 1) was carried out. Expression of EGFR was found in 14/20 polyps and in 22/45 carcinomas. All but one of the EGFR positive malignant tumours showed coexpression of IL-4 receptor. Lymph node involvement by tumour cells was detected in 25 out of 45 patients. Eighteen of these 25 cases were positive with EGFR1.     

Heparin-binding epidermal growth factor-like growth factor isoforms and epidermal growth factor receptor/ErbB1 expression in bladder cancer and their relation to clinical outcome

BACKGROUND: Cleavage of membrane-anchored heparin-binding epidermal growth factor-like growth factor (proHB-EGF) yields a soluble HB-EGF isoform (sHB-EGF), which is an activating epidermal growth factor receptor (EGFR) ligand and a C-terminal fragment HB-EGF-C acting directly in the nucleus. In bladder cancer, overexpression of both HB-EGF and EGFR have been observed, but to the authors' knowledge the prognostic significance of different modes of HB-EGF signaling have remained unclear. METHODS: Expression and intracellular localization of HB-EGF and EGFR were examined by immunohistochemistry in paraffin-embedded specimens from 121 patients who underwent cystectomy for bladder cancer. Tumor stage was pTis/pT1 in 7 patients, pT2 in 41 patients, pT3 in 55 patients, and pT4 in 18 patients. Lymph node metastases were present in 32 patients. RESULTS: Using an antibody directed against the C-terminal domain, HB-EGF expression was detected in the cytoplasm or in the nucleus of tumor cells. EGFR staining was uniform at the plasma membrane. The actuarial 5-year cancer-specific survival of patients with tumors with predominant nuclear HB-EGF staining was 28% compared with 57% if HB-EGF staining was predominantly cytoplasmic (P = .027). Disease outcome of patients with a 'mixed' HB-EGF staining pattern was found to be between that of the 2 former groups. In agreement with previous studies, strong EGFR expression was associated with poor prognosis. Despite strong EGFR expression, predominant cytoplasmic HB-EGF staining was associated with a more favorable outcome, whereas a predominant nuclear pattern defined a subgroup with extremely poor prognosis (5-year tumor-specific survival of 55% vs 13%, respectively; P = .026). CONCLUSIONS: The current study results confirm that EGFR expression is significantly correlated with disease-specific mortality but that the outcome is also influenced by the mode of HB-EGF signaling. Additional nuclear HB-EGF signaling, indicative of increased cleavage of proHB-EGF, appears to enhance the adverse activities. Cytoplasmic HB-EGF staining likely reflects proHB-EGF, which may also exert antiproliferative effects.     

The epidermal growth factor receptor pathway: a model for targeted therapy.

The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase receptor that is frequently expressed in epithelial tumors. The EGFR was the first receptor to be proposed as a target for cancer therapy, and after 2 decades of intensive research, there are several anti-EGFR agents available in the clinic. Recent advances in our understanding in the mechanisms of receptor activation and function, discovery of primary and secondary EGFR somatic mutations, as well as a new generation of anti-EGFR agents provide new leads on the clinical targeting of this receptor and may serve as a model for strategies aimed at targeting other receptors.     

Increase of the epidermal growth factor receptor expression by interferon-beta

The epidermal growth factor receptor (EGF-R) is expressed on both normal and malignant epithelial tissue. Recent efforts in cancer therapy use the EGF-R as a target for an antibody therapy. A further increase of the EGF-R expression possibly by interferon (IFN) could improve the efficacy of such an antibody therapy. The effects of IFN on the EGF-R and on the cell proliferation were first evaluated on a human squamous cell carcinoma cell line HLac 79. Several types of IFN were screened for their influence on the receptor expression by flow cytometric studies. IFN-beta caused a doubling of the measured EGF-R expression at a concentration of 100 IU/ml for 48 h. Scatchard analysis with I-125-EGF after IFN treatment showed a doubling of the EGF-R expression and a third of the receptor affinity compared to untreated cells. These alterations were associated with a decrease of the cell proliferation as measured by a bromodeoxyuridine (BrdU) assay. Results were confirmed with xenografts on NMRI nu/nu mice. IFN-beta (intra tumoral) treated xenografts showed a significantly higher amount of EGF-R (393+/-59 fmol/mg protein) and significantly reduced tumour growth compared to untreated xenografts (262+/-51 fmol/mg protein). This study shows that IFN-beta results in an increase of the EGF-R expression in a carcinoma cell line and in xeno-grafts. Cell proliferation is decreased, resulting in reduced growth of the xenograft.     

Epidermal growth factor receptor and human epidermal growth receptor 2 expression in parotid mucoepidermoid carcinoma: possible implications for targeted therapy

The expression of epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) was analyzed in immunohistochemical preparations from 46 primary parotid mucoepidermoid carcinomas (MEC). For the cases with lymph node metastases, the receptor expressions were investigated in parallel samples, primary tumour and metastasis, from each patient (n=11). The goal was to evaluate whether any of these receptors are suitable as a target for radionuclide-based imaging and therapy. The HercepTest scoring was used for the analysis of both HER2 and EGFR expression (0, 1+, 2+ or 3+). EGFR overexpression (2+/3+) was found in 67.4% (31/46) of the primary tumours. Out of the 11 cases with evaluated paired samples, EGFR overexpression was observed in 81.8% (9/11) of the primary tumours and 72.7% (8/11) of the corresponding lymph node metastases. There was only one patient who had EGFR overexpression in the primary tumours which changed to negative in the lymph node metastases but no changes occurred reciprocally. The HER2 overexpression was only found in 4.3% (2/46) of the primary mucoepidermoid carcinoma and none of the lymph node metastases (0/11). EGFR and HER2 stainings were mainly found in the cell membranes. It was concluded that the majority of parotid mucoepidermoid carcinomas express EGFR strongly in their cell membranes and that lymph node metastases generally express EGFR to approximately the same extent as in the primary tumours. The stability in the EGFR expression is encouraging in the effort to develop radionuclide-based EGFR imaging agents. It is also possible that EGFR targeting agents (e.g. Iressa, Tarceva, Erbitux or radiolabelled antibodies) can be applied for the therapy of mucoepidermoid carcinoma.     

Predicting response to epidermal growth factor receptor-targeted therapy in colorectal cancer

The discovery over 20 years ago by the Nobel Laureate Stanley Cohen of epidermal growth factor and its receptor, followed by the recognition that this receptor is overexpressed in multiple cancer types, has been of phenomenal significance. From these events the ‘Holy Grail’ of targeted therapy has looked increasingly realistic. Over the last 5 years this work has come of age with the licensing of multiple agents targeting this important mitogenic pathway in multiple tumor types. However, these agents and the technology behind them, while impressive, have resulted in lower clinical response rates than anticipated. In this review we will focus on the epidermal growth factor receptor-targeted therapies in colorectal cancer, why our expectations from these therapies have not yet been fulfilled and how we may predict those cancers that are likely to respond or be resistant to these therapies through a greater appreciation of the intricacy, diversity and dynamism of cellular signaling mechanisms.     

Adjuvant inhibition of the epidermal growth factor receptor after fractionated irradiation of FaDu human squamous cell carcinoma.

BACKGROUND AND PURPOSE: Experiments performed by others have shown that inhibition of EGFR before and after single dose irradiation prolonged growth delay and improved local tumour control. This suggests that adjuvant EGFR inhibition can inactivate clonogens that survived irradiation. To test this hypothesis local tumour control was investigated after fractionated radiotherapy and adjuvant EGFR-TK inhibition. MATERIALS AND METHODS: FaDu hSCC xenografts were irradiated with 30 fractions in 6 weeks with total doses of 30-100Gy. After the end of fractionated irradiation, BIBX1382BS was administered daily orally over a time period of 75 days. Tumour volumes were determined two times per week, the volume doubling time during adjuvant treatment was calculated for progressing and recurrent tumours. Local tumour control was investigated 120 days after end of irradiation. RESULTS: Adjuvant BIBX1382BS significantly reduced the tumour growth rate but did not improve local tumour control. The TCD(50) values were 66.1Gy (95% C.I.: 59; 73Gy) after adjuvant BIBX1382BS treatment and 67.9Gy (61; 75Gy) for control tumours (P=0.9). CONCLUSIONS: These data indicate that, although growth of recurrent tumour cells after irradiation is dependent on the EGFR pathway, tumour cells retain their clonogenic potential despite of EGFR inhibition. The results imply also that a decreased tumour growth rate does not necessarily allow conclusions on enhanced inactivation of clonogenic cells when antiproliferative drugs are combined with radiation.     

Predicting response to epidermal growth factor receptor-targeted therapy in colorectal cancer

The discovery over 20 years ago by the Nobel Laureate Stanley Cohen of epidermal growth factor and its receptor, followed by the recognition that this receptor is overexpressed in multiple cancer types, has been of phenomenal significance. From these events the 'Holy Grail' of targeted therapy has looked increasingly realistic. Over the last 5 years this work has come of age with the licensing of multiple agents targeting this important mitogenic pathway in multiple tumor types. However, these agents and the technology behind them, while impressive, have resulted in lower clinical response rates than anticipated. In this review we will focus on the epidermal growth factor receptor-targeted therapies in colorectal cancer, why our expectations from these therapies have not yet been fulfilled and how we may predict those cancers that are likely to respond or be resistant to these therapies through a greater appreciation of the intricacy, diversity and dynamism of cellular signaling mechanisms.     

Racial disparity of epidermal growth factor receptor expression in prostate cancer.

PURPOSE: The epidermal growth factor receptor (EGFR) plays a critical role in prostate cancer (PC) signal transduction and is the target of a novel class of anticancer agents. Despite recent reports of interethnic variation in response to EGFR inhibitors, limited information exists regarding differences in expression of EGFR in PC patients. This has therapeutic relevance because a better understanding of the molecular basis underlying the ethnic variability will help in the design of individualized treatment regimens using EGFR inhibitors. PATIENTS AND METHODS: We investigated EGFR expression in a well-characterized cohort of PC patients to determine the association between EGFR expression and race. Tumor tissues from 202 radical prostatectomies performed between 1990 and 2000 at the Veterans Administration Medical Center (New York, NY) were studied (142 African Americans, 60 whites; median age, 67 years; stage T2, n = 130; stage > or = T3, n = 72; Gleason score < 7, n = 110; Gleason score > or = 7, n = 92). Membrane-specific EGFR expression was evaluated immunohistochemically. RESULTS: EGFR overexpression, defined as complete membrane staining in more than 10% of tumor cells, was observed in 75 of 202 patients (37%). There was a significant association between EGFR overexpression and African American race (P = .0006), higher pretreatment prostate-specific antigen (PSA; P = .02), and stage (P = .02), but not Gleason score (P = .33). The association between African American race and EGFR overexpression remained significant in a multivariate model after controlling for grade, stage, and pretreatment PSA simultaneously (P = .003). CONCLUSION: Our data demonstrate that race contributes significantly to variability of EGFR expression in prostate cancer. Racial background may have an impact on the design of clinical trials to test the efficacy of anti-EGFR agents.     

External and internal radiation therapy: past and future directions

Cancer is a leading cause of morbidity and mortality in the modern world. Treatment modalities comprise radiation therapy, surgery, chemotherapy and hormonal therapy. Radiation therapy can be performed by using external or internal radiation therapy. However, each method has its unique properties which undertakes special role in cancer treatment, this question is brought up that: For cancer treatment, whether external radiation therapy is more efficient or internal radiation therapy one? To answer this question, we need to consider principles and structure of individual methods. In this review, principles and application of each method are considered and finally these two methods are compared with each other.     

Targeting the epidermal growth factor receptor

The epidermal growth factor receptor (EGFR) is a member of the erbB family of tyrosine kinase receptors (RTK). The EGFR is involved in cell proliferation, metastasis and angiogenesis, and is expressed in a large proportion of epithelial tumours. The two main classes of EGFR inhibitors in clinical trials are the RTK inhibitors and the monoclonal antibodies. The clinical development of EGFR inhibitors has introduced new challenges to the design of phase I, II, and III trials. Both classes of agents can be safely administered at doses sufficient to inhibit the EGFR system. Receptor tyrosine kinase inhibitors have been extensively evaluated in non-small-cell lung cancer. In this setting, gefitinib has demonstrated activity in patients who fail initial chemotherapy. Monoclonal antibodies have been developed in combination with cytotoxic chemotherapy in several tumour types, most notably colorectal and head and neck cancer. The preliminary results suggest an increase in response rate and time to progression with the combination of cetuximab and chemotherapy in both disease models. Future issues in the development of EGFR inhibitors include the identification of biologic predictors of response, combination with other targeted agents, and their utilisation in earlier stage malignancies.     

Significance of epidermal growth factor receptor expression in breast cancer

Colorectal cancer is one of the most common cancers worldwide. The anticancer effect of Wolfberry (Lycium barbarum) polysaccharide (LBP) on colon cancer cells is largely unknown. To investigate the growth effect of LBP on human colon cancer cell and its possible mechanisms, human colon cancer SW480 and Caco-2 cells were treated with 100–1,000 mg/l LBP for 1–8 days. Cell growth was measured by MTT assay and crystal violet assay. Distribution of the cell cycle was analyzed by flow cytometry. Western blotting was used to indicate changes in the level of cyclins and cyclin-dependent kinases (CDKs). LBP treatment inhibited both colon cancer cell lines in a dose-dependent manner. At concentrations from 400 to 1,000 mg/l, LBP significantly inhibited the growth of SW480 cells (400 mg/l, P < 0.01; 800 and 1,000 mg/l, P < 0.001); while at concentrations from 200 to 1,000 mg/l, LBP significantly inhibited the growth of Caco-2 cells (200 mg/l, P < 0.05; 400–1,000 mg/l, P < 0.001). Crystal violet assay showed that LBP had a long-term anti-proliferative effect. More importantly, cells were arrested at the G0/G1 phase. The changes in cell-cycle-associated protein, cyclins, and CDKs were consistent with the changes in cell-cycle distribution. This is one of the first studies to focus on LBP-induced interruption of the cell cycle in human colon carcinoma cells. The results suggest that LBP is a candidate anticancer agent.     

Significance of epidermal growth factor receptor expression in breast cancer

Recent interest of many investigators is focused on epidermal growth factor receptor (EGFR) family, because of their potential role in the pathogenesis and progression of breast cancer. Paraffin tumor sections were collected retrospectively from 181 breast cancer patients diagnosed between 2002 and 2003. Immunohistochemical staining with ErbB-1, ErbB-2, ErbB-3, and ErbB-4 monoclonal antibodies was performed. The ErbB expression was correlated with the other clinicopathological variables. Overexpression of ErbB-1, ErbB-2, ErbB-3, and ErbB-4 was observed in 20.6, 18.2, 14.3, and 5.7% cases, respectively. Overexpression of ErbB-1 and ErbB-2 was associated with poor prognostic features and decreased 5-year disease-free survival. The patients with co-overexpression of ErbB-1 and ErbB-2 had a shorter DFS, although this difference was not statistically significant. ErbB-1 overexpression may indicate a subset of patients with a poor disease prognosis. Assays for ErbB-1 and ErbB-2 may be more useful than a single assay in predicting prognosis of a breast cancer patient.     

Significance of epidermal growth factor receptor expression in breast cancer

Recent interest of many investigators is focused on epidermal growth factor receptor (EGFR) family, because of their potential role in the pathogenesis and progression of breast cancer. Paraffin tumor sections were collected retrospectively from 181 breast cancer patients diagnosed between 2002 and 2003. Immunohistochemical staining with ErbB-1, ErbB-2, ErbB-3, and ErbB-4 monoclonal antibodies was performed. The ErbB expression was correlated with the other clinicopathological variables. Overexpression of ErbB-1, ErbB-2, ErbB-3, and ErbB-4 was observed in 20.6, 18.2, 14.3, and 5.7% cases, respectively. Overexpression of ErbB-1 and ErbB-2 was associated with poor prognostic features and decreased 5-year disease-free survival. The patients with co-overexpression of ErbB-1 and ErbB-2 had a shorter DFS, although this difference was not statistically significant. ErbB-1 overexpression may indicate a subset of patients with a poor disease prognosis. Assays for ErbB-1 and ErbB-2 may be more useful than a single assay in predicting prognosis of a breast cancer patient.