Expression of the type 1 tyrosine kinase growth factor receptors EGF receptor, c-erbB2 and c-erbB3 in bladder cancer

Validade dos marcadores tumorais

Considerando-se o número crescente dos chamados marcadores tumorais e a sua incorporação sistemática à prática médica, procedeu-se a um levantamento, por meio de Medline® 1995, na Biblioteca Central do Instituto Nacional de Câncer - INCA, e revisão de 95 resumos de trabalhos publicados de 1995 a abril de 1997. Verificou-se que a validade dos marcadores é maior para o diagnóstico patológico de alguns tipos tumorais e determinação de alguns fatores prognósticos; que poucos são os de real utilidade clínica, seja para prevenção, diagnóstico ou prognóstico, vez que a maioria deles só alcança significância quando a doença já provoca algum sinal ou sintoma; que a maioria das referências correspondem, a rigor, a trabalhos repetidos, que avaliam os mesmos marcadores, embora em diferentes tumores; e que há trabalhos que se referem a poucos casos, quando não pouquíssimos, e cujos resultados tomam-se, por isso, inconsistentes. Neste artigo, os marcadores tumorais são classificados por tipos (genes, expressões genéticas, substâncias circulantes, substâncias celulares, receptores da membrana celular e índices de proliferação tumoral) e por finalidades (prevenção, detecção, diagnóstico, estadiamento, monitoração terapêutica, seguimento pós-tratamento e prognóstico) e são correlacionados com o(s) tumor(es) em que foram pesquisados. Apresentam-se três grupos de critérios de validação (estatísticos, biomédicos e por finalidades) e resume-se, a partir também de mais 16 outras referências bibliográficas, a utilidade de marcadores dos cânceres de mama [ADN, fração de Fase S, índice de ADN, C-erbB-2 (HER-2/neu), P53, CAT-D, CA15.3 e CEA - sem validade; marcadores tumorais hormonais - úteis para a indicação de hormonioterapia adjuvante ou paliativa]; colorretal [LASA, CA 19.9, índice de ADN, fração de Fase S, p53 e ras - sem validade; CEA-com validade para estadiamento e planejamento cirúrgico, e para seguimento pós-operatório (dosagem seriada a cada 2-3 meses por 2 anos, se houve suspeita de metástase hepática em estádios cirúrgicos II e III)] e de próstata (PSA com utilidade para a detecção, mas associado ao toque retal, em homens acima de 40-50 anos, como indicativos da necessidade de exames mais acurados, e para o seguimento dos casos tratados). E inquestionável a utilidade da dosagem de alfa-feto-proteína (aFP) e da gonadotrofina coriônica (hCG), para o estadiamento, tratamento, avaliação da resposta terapêutica e seguimento dos casos tratados de tumores testiculares (aFP e hCG) e de neoplasia trofoblástica gestacional (hCG). Também inquestionável é o papel da identificação dos marcadores de diferenciação celular no diagnóstico patológico de leucemias e linfomas. Os dilemas evidenciados a partir deste estudo referem-se a cinco binômios: 1) ausência de sinal ou sintoma versus positividade de marcador tumoral; 2) detecção de recidiva assintomática versus a qualidade e a quantidade da sobrevida do indivíduo; 3) natureza da causa versus aumento do marcador; 4) exame falso-positivo versus tratamento; e 5) baixo risco de evolução de neoplasia detectada versus tratamento. Conclui-se que, exceto pelos marcadores de validade estabelecida para o diagnóstico, o seguimento do tratamento ou o prognóstico dos casos de alguns cânceres, o médico precisa, além de conhecer os marcadores tumorais e suas siglas, saber os limites das suas indicações e ter opinião, crítica e método na sua utilização.

Study of the Relationship between MMP-2 and MMP-9 and Her2/neu Overexpression in Gastric Cancer: Clinico- Pathological Correlations

Background:

The relationship between the expressions of matrix metalloproteinases with clinico-pathological data on gastric cancer has been investigated in many countries, but this relationship remains unexplored in Iranian patients. Also, the correlation of the MMPs and the HER-2/neu proto-oncogene with other clinic-pathological variables has been evaluated for several other malignancies, but little effort has been made to shed light on the relationship with gastric cancer.

Methods:

We investigated MMP-2 and MMP-9 expression and HERE-2/neu overexpression in 48 gastric cancer patients referred to Afzalipour Hospital, associated with Kerman Medical University. Immunohistochemistry staining with rabbit polyclonal antibodies was used. Data statistical analysis was done by SPSS software (Version 20.0).

Results:

The mean age was 59, most of the patients were male (79.2%), and the average tumor size was larger than 5 centimeters in its greatest diameter. The majority of tumors were of the intestinal subtype and were located in the pyloric and antrum regions (43.8%). Invasion to muscularis properia was seen in 87.5% of the tumors (T3). MMP-2 and MMP-9 were highly expressed in 58.3% and 50% of cases, respectively, and Her-2/neu positivity was 10.4%. MMP-2, MMP-9 and HER-2 were found to have no relation with any clinicopathological parameters.

Conclusion:

According to the results of this study, MMP-2 and MMP-9 were highly expressed in gastric cancer, but there was no significant association with other clinicopathological variables.

New insights into ErbB3 function and therapeutic targeting in cancer

INTRODUCTION

The importance of ErbB3 receptor tyrosine kinase in cancer progression, primary and acquired drug resistance, has become steadily evident since its discovery in 1989. ErbB3 overexpression in various solid organ malignancies is associated with shorter survival of patients. However, initial strategies to therapeutically target ErbB3 have not been rewarding.

AREAS COVERED

Here, we provide an overview of ErbB3 biology in carcinogenesis. We outline the role of ErbB3 as a critical pathway for resistance to other anti-cancer drugs. We focus on emerging clinical data, which will steer the potential future development of ErbB3 directed therapies.

EXPERT OPINION

Initial approaches to ErbB3 targeting have been challenging. However, the lack of success of anti-ErbB3 therapies in ongoing clinical trials may relate more to the complex biology of the receptor and challenges with the biomarkers used to date. Furthermore, it seems certain that the expression of the receptor per se is necessary but not sufficient for the response to ErbB3 therapies. Emerging data suggest that more sophisticated biomarkers are needed. Nonetheless, it is also likely that ErbB3 therapies may have the most efficacy in combination therapy, and their favorable toxicity profile makes this feasible.

Clinicopathologic significance of CXCR4 expressions in patients with esophageal squamous cell carcinoma

AIMS

This study was designed to investigate the biological function of CXCR4 in esophageal squamous cell carcinoma and to explore the underlying mechanism to provide potential targets for esophageal squamous cell carcinoma.

METHODS

A total of 101 patients with esophageal squamous cell carcinoma were included, and the relationship between CXCR4 and clinicopathological factors was analyzed. Laser scanning confocal microscopy was used to observe numbers of autophagosomes in TE-1 cell line and the ability of proliferation and invasion were evaluated meanwhile.

RESULTS

CXCR4 is overexpressed in ESCC specimens and is associated with poor differentiation and lymphocyte metastasis. In the survival analysis, CXCR4 predicted a poor overall survival prognosis. The number of autophagosomes in the siR-CXCR4 group was decreased compared with negative group (P < 0.05), while was increased in the pcDNA3.1-CXCR4 group (P < 0.05).Western blot result show upregulation of LC3II, the ratio of LC3II/LC3I and Beclin1 in pcDNA3.1-CXCR4 group and decreased expression of LC3II, the ratio of LC3II/LC3I and Beclin1 in siR-CXCR4 group. Transwell assay show CXCR4 overexpression promote the invasion of TE-1 cells and was attenuated by autophagy inhibitor 3-Methyladenine.On the contrary, invasion cell numbers decreased in siR-CXCR4 group and was rescued by autophagy inducer Rapamycin.

CONCLUSION

CXCR4 is an indicator of poor prognosis for ESCC. CXCR4 promote autophagy and regulate cell invasion through autophagy in ESCC. Our study provides new insights for the treatment of esophageal squamous cell carcinoma and CXCR4 may serve as a therapeutic target for ESCC.

Upregulation of ADAMTS‑7 and downregulation of COMP are associated with aortic aneurysm

Aortic aneurysm (AA) remains a fatal condition with high rates of morbidity and mortality, and the associated underlying mechanism influencing its pathology remains to be elucidated. A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-7 has previously been demonstrated to be involved in the pathogenesis of vascular atherosclerosis via degradation of cartilage oligomeric matrix protein (COMP). The ADAMTS-7/COMP pathway may therefore act as a potential therapeutic target for vascular disorders. To the best of the author's knowledge, the present study aimed to investigate for the first time, the expression of ADAMTS-7 and COMP in human AA. Human aortic aneurysm samples were collected from patients with AA (n=24), and ascending aorta control samples were harvested from dilated cardiomyopathy patients who underwent heart transplantation (n=18). Expression levels of ADAMTS-7 and matrix metalloproteinase-9 were significantly increased in the AA group, as detected by immunohistochemistry (P<0.05). The COMP protein level was markedly decreased in the AA group when compared with the control group, as demonstrated via immunohistochemistry and western blot analysis (P<0.05). The findings suggest that upregulation of ADAMTS-7 and downregulation of COMP are associated with induction of human AA. ADAMTS-7/COMP pathway may provide therefore act as a potential therapeutic target in human AA for efficient, optimal treatment interventions in the future.

Evaluation of MMP-9 and MMP-2 and their suppressor TIMP-1 and TIMP-2 in adenocarcinoma of esophagogastric junction

OBJECTIVE

Adenocarcinoma of esophagogastric junction (AEG) is a lethal malignancy featured with early metastasis, poor prognosis, and few treatment options. Matrix metalloproteinase (MMP) and metalloproteinase suppressor (TIMP) have been considered to be associated with cancer invasion and metastasis. In our study, we evaluated expressions of MMP-9, MMP-2, TIMP-1, and TIMP-2 in AEG and their correlation with clinicopathological parameters and the overall survival rate.

METHODS

Expressions of MMP-9, MMP-2, TIMP-1, and TIMP-2 in specimens from 120 AEGs were detected by immunohistochemistry. The correlations between expressions of these four proteins and clinicopathological characters were analyzed by chi-square test. Moreover, the prognostic value of these four biomarkers was evaluated by univariate analysis with Kaplan-Meier method and multivariate analysis with Cox regression model.

RESULTS

The positive expression rate of MMP-9, MMP-2, TIMP-1, and TIMP-2 was 65%, 53%, 70%, and 49%, respectively, in the detected 120 AEG samples. MMP-9 was significantly associated with poorly histological differentiation (P=0.001), lymph node metastasis (P=0.007), and UICC stage (P=0.008). TIMP-1 showed significantly reversed correlations with histological differentiation (P=0.001), lymph node metastasis (P=0.007), and Union for International Cancer Control stage (P=0.008). Univariate analysis revealed that lymph node metastasis (P=0.002), depth of invasion (P=0.050), and MMP-9+/TIMP-1 phonotype (P<0.001) were significantly associated with the overall survival rate. Multivariate analyses demonstrated that MMP-9+/TIMP-1-phenotype was an independent prognostic factor in AEGs.

CONCLUSION

Detection of MMP-9 and TIMP-1 expression allows stratification of AEG patients into different survival categories and can be useful for precise individual evaluation and survival prediction.

Clinical significance of cyclophilin a expression in esophageal squamous cell carcinoma

OBJECTIVE

To explore the expression of cyclophilin A (CypA) in esophageal tissues and its clinical significance.

METHOD

Expression of CypA was detected in 236 esophageal cancer tissues and 236 normal tissues by using an immunohistochemical method, and the relationship between CypA expression and clinical outcomes was observed.

RESULTS

There were 166 patients with high expression of CypA (70.23%) and a higher expression in 69.3% of males and 73.3% in females. The CypA expression was irrelevant to age, tumor location, lymph node metastasis, and tumor differentiation degree. The Kaplan-Meier survival curve analysis showed that the expression of CypA was associated with the prognosis of patients with esophageal squamous cell carcinoma.

CONCLUSION

The poor prognosis of esophageal cancer patients was associated with high expression of CypA.

Characterization of EGFR family gene aberrations in cholangiocarcinoma

Cholangiocarcinoma (CCA) is a highly lethal malignancy of the biliary tract with very few treatment options. Epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor (HER2) have been considered as potential therapeutic targets in CCA. In the present study, we attempted to clarify the clinicopathological significance of all EGFR family members, EGFR, HER2, HER3 and HER4, across the full spectrum of CCAs. Immunohistochemistry and FISH were performed to validate expressions and genetic aberrations of these molecules retrospectively in 175 CCA patients. EGFR, HER3 and HER4 were overexpressed in 20 (30.8%), 8 (12.3%) and 41 (63.1%) of the 65 intrahepatic cholangiocarcinomas (IHCCs), and in 23 (20.9%), 13 (11.8%) and 62 (56.4%) of the 110 extrahepatic cholangiocarcinomas (EHCCs), respectively. Overexpression of HER2 was exclusively identified in EHCCs, among which the rate was 4.5% (5/110). A significant association was identified between EGFR amplification and EGFR overexpression (P=0.002). Similarly, HER2 amplification was strongly associated with HER2 overexpression (P<0.001). Multivariate analysis suggested that EGFR overexpression is an independent prognostic factor in IHCC, but not in EHCC cases [HR (95% CI): 3.689 (1.253-10.587), P=0.018]. Notably, for the first time, we demonstrated HER4 expression is a prognostic factor in EGFR-negative IHCC patients. In vitro data further suggested a tumor-suppressor role of HER4 in CCA. siRNA knockdown of HER4 significantly increased RBE cell migration and invasion. By contrast, HER4 overexpression decreased proliferation of HuCCT-1 cells and their migratory and invasive capacity. In summary, our results revealed expression of the EGFR family members in CCA development and progression. CCAs differentially express HER2 protein based on tumor location. HER4 expression status allows stratification of CCA patients into different survival categories.

Peptide vaccines and targeting HER and VEGF proteins may offer a potentially new paradigm in cancer immunotherapy

The ErbB family (HER-1, HER-2, HER-3 and HER-4) of receptor tyrosine kinases has been the focus of cancer immunotherapeutic strategies while antiangiogenic therapies have focused on VEGF and its receptors VEGFR-1 and VEGFR-2. Agents targeting receptor tyrosine kinases in oncology include therapeutic antibodies to receptor tyrosine kinase ligands or the receptors themselves, and small-molecule inhibitors. Many of the US FDA-approved therapies targeting HER-2 and VEGF exhibit unacceptable toxicities, and show problems of efficacy, development of resistance and unacceptable safety profiles that continue to hamper their clinical progress. The combination of different peptide vaccines and peptidomimetics targeting specific molecular pathways that are dysregulated in tumors may potentiate anticancer immune responses, bypass immune tolerance and circumvent resistance mechanisms. The focus of this review is to discuss efforts in our laboratory spanning two decades of rationally developing peptide vaccines and therapeutics for breast cancer. This review highlights the prospective benefit of a new, untapped category of therapies biologically targeted to EGF receptor (HER-1), HER-2 and VEGF with potential peptide 'blockbusters' that could lay the foundation of a new paradigm in cancer immunotherapy by creating clinical breakthroughs for safe and efficacious cancer cures.

miR-143, miR-222, and miR-452 are useful as tumor stratification and noninvasive diagnostic biomarkers for bladder cancer

Altered microRNA (miRNA) expression may occur early in bladder cancer and may play a role in carcinogenesis and tumor behavior. We evaluated whether alterations in miRNA expression could improve disease stratification and outcome prognosis in bladder tumors and noninvasive diagnosis in urinary samples. miR-143, miR-222, and miR-452 expression levels were analyzed by quantitative RT-PCR (RT-qPCR) in paired urinary and matching tumors and in two independent prospective series of tumors and urinary specimens. Differential expression of miR-143, miR-222, and miR-452 in urine were verified by in situ hybridization in matching tumors. Tumor miRNA expression by RT-qPCR correlated with tumor grade, size, and presence of carcinoma in situ for miR-222, recurrence (miR-222 and miR-143), progression (miR-222 and miR-143), disease-specific survival (miR-222), and overall survival (miR-222). Protein expression patterns of potential miRNA targets, including vascular endothelial growth factor, BCL2, v-erb-b2 erythroblastic leukemia viral oncogene (ERBB) homolog 3, and ERBB4, were evaluated by IHC in tissue arrays containing tumors for which miRNAs were assessed by RT-qPCR. Target expression correlated with expression of their predicted regulatory miRNAs, recurrence (ERBB3), progression (ERBB4), disease-specific survival (ERBB3 and ERBB4), and overall survival (ERBB3 and ERBB4). Furthermore, RT-qPCR of miR-452 (area under the curve, 0.848) and miR-222 (area under the curve, 0.718) in urine provided high accuracies for bladder cancer diagnosis. Thus, bladder tumors were characterized by changes in miRNA expression that could aid in tumor stratification and clinical outcome prognosis, and miRNAs were detected in urinary specimens for noninvasive diagnosis.

Prognostic implications of altered human epidermal growth factor receptors (HERs) in gastric carcinomas: HER2 and HER3 are predictors of poor outcome

PURPOSE

The human epidermal growth factor receptor (HER) family consists of four members: ErbB-1 (HER1), ErbB-2 (HER2), ErbB-3 (HER3), and ErbB-4 (HER4). These receptors activate numerous downstream pathways in response to extracellular ligands, regulating diverse processes that include differentiation, migration, proliferation, and survival. Alterations in these genes play a role in the development and progression of many human cancers. In gastric carcinomas (GCs), expression of HER1 and HER2 is thought to be a prognostic factor and target of novel biologic agents. The effect of HER3 or HER4 expression in GC has not been sufficiently studied. In this study, we explored the gene and protein expression of the HER family in GC to establish new potential prognostic factors.

PATIENTS AND METHODS

Immunohistochemistry and fluorescence in situ hybridization were performed in 221 patients with GC using tissue microarray. Correlation between the expression or amplification of HER genes and the clinicopathologic parameters was statistically analyzed.

RESULTS

Alterations of members of the HER family were significantly associated with the parameters involved in tumor progression, including depth of tumor invasion, involved lymph nodes, and tumor stage. In addition, HER2 amplification and HER3 expression were significantly related to worse survival.

CONCLUSION

These results reveal that all members of the HER family are expressed in GC. Furthermore, expression of HER2 and HER3 is a significant predictor of poor survival in GC. Therefore, the development of HER-targeted agents and agents targeting downstream signaling pathways provides new possibilities in the treatment of GC.

Expression of NRG1 and its receptors in human bladder cancer

BACKGROUND

Therapies targeting ERBB2 have shown success in the clinic. However, response is not determined solely by expression of ERBB2. Levels of ERBB3, its preferred heterodimerisation partner and ERBB ligands may also have a role.

METHODS

We measured NRG1 expression by real-time quantitative RT-PCR and ERBB receptors by western blotting and immunohistochemistry in bladder tumours and cell lines.

RESULTS

NRG1α and NRG1β showed significant coordinate expression. NRG1β was upregulated in 78% of cell lines. In tumours, there was a greater range of expression with a trend towards increased NRG1α with higher stage and grade. Increased expression of ERBB proteins was detected in 15% (EGFR), 20% (ERBB2), 41% (ERBB3) and 0% (ERBB4) of cell lines. High EGFR expression was detected in 28% of tumours, associated with grade and stage (P=0.05; P=0.04). Moderate or high expression of ERBB2 was detected in 22% and was associated with stage (P=0.025). Cytoplasmic ERBB3 was associated with high tumour grade (P=0.01) and with ERBB2 positivity. In cell lines, NRG1β expression was significantly inversely related to ERBB3, but this was not confirmed in tumours.

CONCLUSION

There is a wide spectrum of NRG1 and ERBB receptor expression in bladder cancer. In advanced tumours, EGFR, ERBB2 and ERBB3 upregulation is common and there is a relationship between expression of ERBB2 and ERBB3 but not the NRG1 ligand.

Combining phage and staphylococcal surface display for generation of ErbB3-specific Affibody molecules

Emerging evidence suggests that the catalytically inactive ErbB3 (HER3) protein plays a fundamental role in normal tyrosine kinase receptor signaling as well as in aberrant functioning of these signaling pathways, resulting in several forms of human cancers. ErbB3 has recently also been implicated in resistance to ErbB2-targeting therapies. Here we report the generation of high-affinity ErbB3-specific Affibody molecules intended for future molecular imaging and biotherapeutic applications. Using a high-complexity phage-displayed Affibody library, a number of ErbB3 binders were isolated and specific cell-binding activity was demonstrated in immunofluorescence microscopic studies. Subsequently, a second-generation library was constructed based on sequences of the candidates from the phage display selection. By exploiting the sensitive affinity discrimination capacity of a novel bacterial surface display technology, the affinity of candidate Affibody molecules was further increased down to subnanomolar affinity. In summary, the demonstrated specific targeting of native ErbB3 receptor on human cancer cell lines as well as competition with the heregulin/ErbB3 interaction indicates that these novel biological agents may become useful tools for diagnostic and therapeutic targeting of ErbB3-expressing cancers. Our studies also highlight the powerful approach of combining the advantages of different display technologies for generation of functional high-affinity protein-based binders. Potential future applications, such as radionuclide-based diagnosis and treatment of human cancers are discussed.

Systemic therapy of metastatic bladder cancer in the molecular era: current status and future promise

IMPORTANCE OF THE FIELD

Platinum-based chemotherapy is considered the standard-of-care first-line therapy for metastatic bladder cancer. Despite the initial high response rate, the vast majority of patients eventually progress and succumb to their disease, urging the need for development of novel therapies.

AREAS COVERED IN THIS REVIEW

This article discusses the main signaling pathways implicated in the pathogenesis of bladder carcinomas, reviews recently completed and ongoing clinical trials, and anticipates the future direction of molecularly targeted agents.

WHAT THE READER WILL GAIN

This manuscript presents the current status of conventional chemotherapy in advanced bladder cancer, and provides a comprehensive review of molecular targeted agents currently in clinical development for this disease.

TAKE HOME MESSAGE

Improved understanding of the biology of urothelial carcinogenesis has paved the way for the development of novel molecularly targeted therapies, several of which are currently tested in clinical trials. In this regard, VEGF and EGFR pathways are emerging as important therapeutic targets for metastatic bladder cancer, either alone or in combination with conventional chemotherapeutics. Other therapies, including aurora kinase inhibitors, endothelin receptor antagonists, RAS/MAPK pathway inhibitors and novel immunologic strategies, may also prove helpful in the treatment of this disease.

Comparison of global versus epidermal growth factor receptor pathway profiling for prediction of lapatinib sensitivity in bladder cancer

Chemotherapy for metastatic bladder cancer is rarely curative. The recently developed small molecule, lapatinib, a dual epidermal growth factor receptor (EGFR)/human epidermal growth factor receptor-2 receptor tyrosine kinase inhibitor, might improve this situation. Recent findings suggest that identifying which patients are likely to benefit from targeted therapies is beneficial, although controversy remains regarding what types of evaluation might yield optimal candidate biomarkers of sensitivity. Here, we address this issue by developing and comparing lapatinib sensitivity prediction models for human bladder cancer cells. After empirically determining in vitro sensitivities (drug concentration necessary to cause a 50% growth inhibition) of a panel of 39 such lines to lapatinib treatment, we developed prediction models based on profiling the baseline transcriptome, the phosphorylation status of EGFR pathway signaling targets, or a combination of both data sets. We observed that models derived from microarray gene expression data showed better prediction performance (93%-98% accuracy) compared with models derived from EGFR pathway profiling of 23 selected phosphoproteins known to be involved in EGFR-driven signaling (54%-61% accuracy) or from a subset of the microarray data for transcripts in the EGFR pathway (86% accuracy). Combining microarray data and phosphoprotein profiling provided a combination model with 98% accuracy. Our findings suggest that transcriptome-wide profiling for biomarkers of lapatinib sensitivity in cancer cells provides models with excellent predictive performance and may be effectively combined with EGFR pathway phosphoprotein profiling data. These results have significant implications for the use of such tools in personalizing the approach to cancers treated with EGFR-directed targeted therapies.

Management of bladder cancer: current and emerging strategies

Cancer of the urinary bladder is the fifth most prevalent solid tumour in the US. Urothelial carcinoma is the most common form of bladder cancer, accounting for about 90% of cases. About 25% of patients with bladder cancer have advanced disease (muscle-invasive or metastatic disease) at presentation and are candidates for systemic chemotherapy. Urothelial carcinoma is a chemo-sensitive disease, with a high overall and complete response rate to combination chemotherapy. In the setting of muscle-invasive urothelial carcinoma, use of neoadjuvant chemotherapy is associated with overall survival benefit. The role of adjuvant chemotherapy in this setting is yet to be validated. In the setting of metastatic disease, use of cisplatin-based regimens improves survival. However, despite initial high response rates, the responses are typically not durable leading to recurrence and death in the vast majority of these patients. Currently, there is no standard second-line therapy for patients in whom first-line chemotherapy for metastatic disease has failed. Many newer chemotherapeutic agents have shown modest activity in urothelial carcinoma. Improved understanding of molecular biology and pathogenesis of urothelial carcinoma has opened avenues for the use of molecularly targeted therapies, several of which are being tested in clinical trials. Currently, several novel drugs seem particularly promising including inhibitors of the epidermal growth factor receptor pathway, such as cetuximab, and inhibitors of tumour angiogenesis, such as bevacizumab and sunitinib. Development of reliable molecular predictive markers is expected to improve treatment decisions, therapy development and outcomes in urothelial carcinoma. Funding of and participation in clinical trials are key to advancing the care of urothelial cancer patients. Current and emerging strategies in the medical management of urothelial carcinoma are reviewed.

The ERBB3 receptor in cancer and cancer gene therapy

ERBB3, a member of the epidermal growth factor receptor (EGFR) family, is unique in that its tyrosine kinase domain is functionally defective. It is activated by neuregulins, by other ERBB and nonERBB receptors as well as by other kinases, and by novel mechanisms. Downstream it interacts prominently with the phosphoinositol 3-kinase/AKT survival/mitogenic pathway, but also with GRB, SHC, SRC, ABL, rasGAP, SYK and the transcription regulator EBP1. There are likely important but poorly understood roles for nuclear localization and for secreted isoforms. Studies of ERBB3 expression in primary cancers and of its mechanistic contributions in cultured cells have implicated it, with varying degrees of certainty, with causation or sustenance of cancers of the breast, ovary, prostate, certain brain cells, retina, melanocytes, colon, pancreas, stomach, oral cavity and lung. Recent results link high ERBB3 activity with escape from therapy targeting other ERBBs in lung and breast cancers. Thus a wide and centrally important role for ERBB3 in cancer is becoming increasingly apparent. Several approaches for targeting ERBB3 in cancers have been tested or proposed. Small inhibitory RNA (siRNA) to ERBB3 or AKT is showing promise as a therapeutic approach to treatment of lung adenocarcinoma.

Nuclear translocation of HER-4/c-erbB-4 is significantly correlated with prognosis of esophageal squamous cell carcinoma

BACKGROUND

HER family is an attractive target for the treatment of esophageal cancer. The clinical relevance of HER-4 has not been yet characterized.

METHODS

The expression of HER-4 was immunohistochemically examined in 61 surgically resected esophageal squamous cell carcinomas (ESCC), and the prognostic significance of HER-4 in ESCC was evaluated.

RESULTS

HER-4 was positive in the cytoplasm and cell membrane of 51 (84%) tumors, with variable intensity and a heterogeneous distribution, with preferential expression in well or moderately differentiated tumors. Nuclear staining of HER-4 was observed in 37 (61%) cases as well. The membranous/cytoplasmic, but not nuclear, expression of HER-4 was positively correlated with the expression of HER-2 and HER-3. Survival of the HER-4-positive group was significantly better than that of the HER-4-negative group (P < 0.05). Multivariate analysis revealed that extranuclear expression of HER-4 was independently correlated with increased survival. In contrast, nuclear staining of HER-4 was correlated with increased T stage, which resulted in a significant reduction in survival in the HER-4 positive group (P < 0.05).

CONCLUSION

Extranuclear HER-4 may have negative effects on the progression of ESCC, whereas nuclear translocation of HER-4 may elicit a tumor-promoting property. Immunohistochemical detection of HER-4 localization is clinically useful to predict the survival of the patients with ESCC.

Distinctive expression pattern of ErbB family receptors signifies an aggressive variant of bladder cancer

PURPOSE

Expression of various members of the ErbB family (epidermal growth factor receptor/ErbB-1, ErbB-2, ErbB-3 and ErbB-4) is associated with disease stage and survival in patients with urothelial carcinoma. We examined the correlation of ErbB family receptor expression with the progression of urothelial carcinoma and survival.

MATERIALS AND METHODS

A urothelial carcinoma tissue array was constructed from 248 archival paraffin blocks and quality control studies were ascertained. The tissue microarray was stained for epidermal growth factor receptor, ErbB-2, ErbB-3 and ErbB-4, and analyzed using an automated reader. Patient data included grade, stage, growth pattern, recurrence and survival.

RESULTS

Kaplan-Meier estimates of 5-year overall and recurrence-free survival were 58% and 27%, respectively. Patients with high grade, invasive or nonpapillary disease had a worse prognosis than patients with low grade, superficial or papillary disease (p <0.0001). High epidermal growth factor receptor or low ErbB-4 expression was associated with nonpapillary, high grade and invasive tumors as well as with significantly shorter recurrence-free and overall survival (p <0.002, 0.028 and 0.047, respectively). Levels of ErbB-2 and ErbB-3 expression were not associated with overall or recurrence-free survival.

CONCLUSIONS

The expression profiles of ErbB-4 and epidermal growth factor receptor are prognostic in urothelial carcinoma. They may help in selecting patients at high risk with bladder cancer for more aggressive therapy.

Identification and characterization of novel spliced variants of neuregulin 4 in prostate cancer

PURPOSE

The neuregulin (NRG) 1, 2, and 3 genes undergo extensive alternative mRNA splicing, which results in variants that show structural and functional diversity. The aims of this study were to establish whether the fourth member of this family, NRG4, is expressed in prostate cancer, if it is alternatively spliced and whether any functional differences between the variants could be observed.

EXPERIMENTAL DESIGN

The expression of NRG4 was determined using immunohistochemical staining of 40 cases of primary prostate cancer. Bioinformatic analysis and reverse transcription-PCR (RT-PCR) using NRG4 isotype-specific primers on a panel of normal and prostate cancer cell lines were used to identify alternatively spliced NRG4 variants. Expression of these variants was determined using isotype-specific antibodies. Transfection into Cos-7 cells of two of these green fluorescent protein-tagged variants allowed analysis of their subcellular location. Four of the variants were chemically synthesized and tested for their ability to activate the ErbB4 receptor.

RESULTS

NRG4 was variably expressed in the cytoplasm in the majority of prostate cancer cases, and in a subset of cases in the membrane, high levels were associated with advanced disease stage. Four novel NRG4 splice variants (NRGA2, NRG4 B1-3) were characterized, where each seemed to have a different subcellular location and were also expressed in the cytoplasm of the prostate tumors. NRG4 B3 was also present in endothelial cells. In transfected cells, the A type variant (NRG4 A1) was localized to the membrane, whereas the B type variant (NRG4 B1), which lacks the predicted transmembrane region, had an intracellular localization. Only the variants with an intact epidermal growth factor-like domain activated ErbB4 signaling.

CONCLUSION

NRG4 overexpression is associated with advanced-stage prostate cancer. The alternative splice variants may have different roles in cell signaling, some acting as classic receptor ligands and some with as-yet unknown functions.

Role of HER2/HER3 co-receptor in breast carcinogenesis

ErbB receptors are essential mediators of cell proliferation and differentiation. Their aberrant activation is associated with the development and severity of many cancers. Homo- and heterodimerization of ErbB receptors result in a wide variety of cellular signal transduction. Dimerization of human epidermal growth-factor receptor (HER)2 and HER3 occurs frequently and is a preferred heterodimer. The HER2/HER3 dimer constitutes a high affinity co-receptor for heregulin, which is capable of potent mitogenic signaling. HER3 is a kinase-defective protein that is phosphorylated by HER2. Tyrosine phosphorylated HER3 is able to directly couple to phosphatidylinositide 3-kinase, a lipid kinase involved in the proliferation, survival, adhesion and motility of tumor cells. The authors' research provides mechanistic evidence that apigenin induces apoptosis by depleting the HER2 protein and, in turn, suppressing the signaling of the HER2/HER3-phosphatidylinositide 3-kinase/Akt pathway. This indicates that inhibition of HER2/HER3 heterodimer function may be an especially effective and unique strategy for blocking the HER2-mediated carcinogenesis of breast cancer cells.

ErbB-3 predicts survival in ovarian cancer

BACKGROUND

HER3 (erbB-3) is a member of the epidermal growth factor receptor (EGFR) family. After dimerization with other members of the EGFR family several signal transduction cascades can be activated, including phosphoinosite 3'-kinase (PI3-K)/Akt and extracellular signal-regulated kinase (ERK1/2). Here, we studied a possible association between HER3 expression and prognosis in patients with ovarian cancer.

METHODS

Tumor tissue of 116 consecutive patients diagnosed with primary epithelial ovarian cancer between 1986 and 1995 was analyzed immunohistochemically for HER3 expression. A possible influence of HER3 expression on survival was studied by multivariate Cox regression adjusting for established clinical prognostic factors.

RESULTS

A positive HER3 expression was observed in 53.4% of the patients. HER3 expression was associated with decreased survival in proportional hazard modeling, including the International Federation of Gynecology and Obstetrics (FIGO) stage, histologic grade and type, residual disease, and age. After likelihood ratio forward as well as backward selection, only HER3 expression (hazard ratio, 1.71; 95% CI, 1.10 to 2.67; P = .018), FIGO stage (hazard ratio, 4.78; 95% CI, 1.89 to 12.08; P = .001), residual tumor (hazard ratio, 2.69; 95% CI, 1.40 to 5.17; P = .003), and age (hazard ratio, 2.06; 95% CI, 1.17 to 3.65; P = .013) were found to be significant. Kaplan-Meier plots demonstrated a clear influence of HER3 expression on survival time. Median survival time was 3.31 years (95% CI, 1.93 to 4.68) for patients with low HER3 expression, compared with only 1.80 years (95% CI, 0.83 to 2.78) for patients with HER3 overexpression (log-rank test P = .0034).

CONCLUSION

HER3 may represent a new prognostic factor in primary epithelial ovarian cancer. Pending validation, exploration of therapeutic strategies to block HER3 could be warranted.

Is Quantitative Real-Time RT-PCR an Adjunct to Immunohistochemistry for the Evaluation of ErbB2 Status in Transitional Carcinoma of the Bladder?

OBJECTIVE

To test different approaches of evaluation of the ErbB2 status in a large series of human transitional cell carcinoma (TCC) of the bladder with the prospect of finding targeted therapies.

METHODS

ErbB2 status of 73 human TCC samples was analyzed by both immunohistochemistry (IHC) and by quantification of mRNA levels of expression using real-time reverse transcription-polymerase chain reaction (RT-PCR). Additionally, 18 bladder samples were studied for ERBB2 gene amplification by real-time quantitative PCR.

RESULTS

Twenty-five tumors (34.2%) overexpressed ERBB2 mRNA compared to normal bladder samples; this alteration appeared in low-grade and low-stage tumors (pTaG1). Twenty-four (32.9%) tumors showed moderate (++) or strong (+++) immunostaining. A very strong agreement was found between the two methods (kappa = 0.97, 95% confidence interval, 0.90-1). ErbB2 status was not associated with tumor stage. Of the 18 bladder samples tested for ERBB2 gene amplification, only one showed ERBB2 DNA amplification.

CONCLUSIONS

ErbB2 overexpression occurs in about one third of bladder TCCs. This overexpression can be detected by RT-PCR with a very good correlation with IHC. RT-PCR can therefore be used for cases considered doubtful on IHC rather than gene amplification studies because, in TCC, gene amplification is not the predominant mechanism of both mRNA and protein overexpression. Accurate quantification of ErbB2 status is mandatory for the use of anti-ErbB2-targeted therapies in bladder TCC.

Expression of the epidermal growth factor receptor family in normal and malignant urothelium

OBJECTIVE

To compare the immunohistochemically assessed expression of the epidermal growth factor receptor (EGFR) family in normal and malignant bladder urothelium, and suggest new hypotheses about their function in the development and progression of transitional cell carcinoma (TCC).

PATIENTS AND METHODS

EGFR, ERBB2, ERBB3 and ERBB4 were evaluated immunohistochemically in normal urothelium (NU, 15), primary non-metastasized invasive TCC (NMC, 19) and in primary invasive TCCs with corresponding metastases (MC, 51, both specimens).

RESULTS

All NU samples expressed ERBB4, none expressed ERBB2 and two expressed EGFR; all staining was uniform throughout all cell layers. ERBB2 expression increased and ERBB4 decreased from normal samples to carcinomas. There was no difference between NMCs and MCs in ERBB2, ERBB3 and ERBB4, but the NMCs expressed more EGFR than both NU and MC samples. There were no associations with T category, grade or survival. All combinations of expression levels for the four receptors were detected, with no dominant profile.

CONCLUSION

We hypothesise that: (i) ERBB4 is important for differentiation in NU; (ii) ERBB2 is up-regulated with carcinogenesis in the urinary bladder but does not discriminate between bladder cancer with or without metastases; (iii) EGFR may be a marker of indolent disease. A current hypothesis, that superficial layers of NU do not express EGFR and thus protect the basal cells from the mitogenic effect of urinary EGF, is challenged.

Apigenin induces apoptosis through proteasomal degradation of HER2/neu in HER2/neu-overexpressing breast cancer cells via the phosphatidylinositol 3-kinase/Akt-dependent pathway

Apigenin is a low toxicity and non-mutagenic phytopolyphenol and protein kinase inhibitor. It exhibits anti-proliferating effects on human breast cancer cells. Here we examined several human breast cancer cell lines having different levels of HER2/neu expression and found that apigenin exhibited potent growth-inhibitory activity in HER2/neu-overexpressing breast cancer cells but was much less effective for those cells expressing basal levels of HER2/neu. Induction of apoptosis was also observed in HER2/neu-overexpressing breast cancer cells in a dose- and time-dependent manner. However, the one or more molecular mechanisms of apigenin-induced apoptosis in HER2/neu-overexpressing breast cancer cells remained to be elucidated. A cell survival pathway involving phosphatidylinositol 3-kinase (PI3K), and Akt is known to play an important role in inhibiting apoptosis in response to HER2/neu-overexpressing breast cancer cells, which prompted us to investigate whether this pathway plays a role in apigenin-induced apoptosis in HER2/neu-overexpressing breast cancer cells. Our results showed that apigenin inhibits Akt function in tumor cells in a complex manner. First, apigenin directly inhibited the PI3K activity while indirectly inhibiting the Akt kinase activity. Second, inhibition of HER2/neu autophosphorylation and transphosphorylation resulting from depleting HER2/neu protein in vivo was also observed. In addition, apigenin inhibited Akt kinase activity by preventing the docking of PI3K to HER2/HER3 heterodimers. Therefore, we proposed that apigenin-induced cellular effects result from loss of HER2/neu and HER3 expression with subsequent inactivation of PI3K and AKT in cells that are dependent on this pathway for cell proliferation and inhibition of apoptosis. This implies that the inhibition of the HER2/HER3 heterodimer function provided an especially effective strategy for blocking the HER2/neu-mediated transformation of breast cancer cells. Our results also demonstrated that apigenin dissociated the complex of HER2/neu and GRP94 that preceded the depletion of HER2/neu. Apigenin-induced degradation of mature HER2/neu involves polyubiquitination of HER2/neu and subsequent hydrolysis by the proteasome.

Overview of bladder cancer trials in the Cancer and Leukemia Group B

The Cancer and Leukemia Group B (CALGB) Genitourinary Committee has developed a broad range of clinical trials across most stages of bladder cancer. Recurrence rates of superficial bladder cancer after transurethral resection range from 50-70%. Although adjuvant bacillus Calmette-Guerin reduces the risk of disease recurrence or progression, only 30% of patients have long-term disease-free survival. Because the development of novel secondline agents is needed, the CALGB is evaluating the utility of intravesicle gemcitabine as well as an oral proapoptotic agent (CP-461). In patients with locally advanced disease with an increased risk of disease recurrence after cystectomy, a randomized trial of conventional chemotherapy versus sequential dose-dense therapy is under development. The gemcitabine/cisplatin combination has become a commonly used regimen for the treatment of advanced transitional cell carcinoma (TCC). The CALGB is undertaking a Phase II study that incorporates a fixed dose rate gemcitabine infusion in this regimen, together with a selective epidermal growth factor receptor tyrosine kinase inhibitor, Iressa (Astra Zeneca, Wilmington, DE). In patients with renal insufficiency, a regimen of carboplatin, gemcitabine, and Iressa is planned. Novel agents, including arsenic trioxide and trastuzumab (Herceptin; Genentech, Inc., South San Francisco, CA), are being evaluated as secondline therapy in patients with advanced TCC who have disease progression after frontline therapy.

Appraisal of differentiation markers in urothelial cells

The expression, subcellular localization, and supramolecular organization of structural and differentiation-related proteins were studied in differentiating superficial cells during regeneration of the rat urothelium. Cytokeratin 17 and epidermal growth factor receptor were expressed in undifferentiated cells, whereas in differentiated superficial cells, this expression ceased. beta-Actin was expressed in undifferentiated and in differentiated cells, but subcellular localization markedly changed by its withdrawal from apical region during differentiation. In differentiating cells, cytokeratin 20 was first observed as diffusely arranged spots distributed throughout the cytoplasm; later, it became organized as a network in the apical part of the cells. Urothelium specific proteins, uroplakins, were weakly expressed at early states of differentiation, but only in terminally differentiated cells did they organize into asymmetric unit membrane plaques. These findings show that in some cases, expression is a sufficient marker of cell differentiation. In other cases, however, the specific subcellular localization and supramolecular organization of proteins should be considered. It is evident that choosing the appropriate methods is crucial for precise evaluation of the urothelial differentiation states.

Differential C-erbB-2 and VEGF expression following BCG immunotherapy in superficial papillary transitional cell carcinoma of the bladder

Bacillus Calmette Guerin (BCG) is generally regarded as an effective immunotherapy for superficially invasive papillary transitional cell carcinoma of the bladder. The exact mechanism(s) which underlie its efficacy are unknown. As C-erbB-2 oncoprotein and vascular endothelial growth factor (VEGF) have been shown to be over-expressed in TCC of the bladder, it has been postulated that they may be important in its pathogenesis. The purpose of this study was to 1.) differentially evaluate the effect of BCG immunotherapy in treated and untreated cohorts on the immunohistochemical expression of C-erbB-2 and VEGF in formalin-fixed paraffin-embedded sections of superficial and superficially invasive (Stage Ta-T1) transitional cell carcinoma of the bladder. Immunolabeling intensity was assessed independently by two pathologists and reported as a mean labeling index. The results confirm previous studies that 1.) both c-erbB-2 and VEGF are over-expressed in these tumors MLI = 90.1 and 45.7 respectively, 2.) that VEGF is an early and sensitive indicator of TCC, and 3.) that BCG has a salutary effect on papillary TCC, 66% vs. 89% recurrence rate, P = .04. Our findings show that 1.) C-erbB-2 expression is decreased in patients tumors which show response to BCG (45.7 to 38.5), P = 0.15, 2.) that BCG administration has no effect on the expression of VEGF. While the decrement in c-erbB-2 immunostaining observed in those patients who received BCG contrasts with the increase in c-erbB-2 immunolabeling observed in patients who did not receive BCG, the differences were not statistically significant and could reflect tumor grade or stage regression associated with BCG therapy. However, this study suggests that BCG differentially influences the expression of C-erbB-2 and VEGF.

Increased expression of c-erbB-3 protein and proliferating cell nuclear antigen during development of verrucous carcinoma of the oral mucosa

BACKGROUND

The roles of c-erbB-3 gene and protein in the pathogenesis, progression, and outcome of oral carcinoma remain unknown. To determine whether c-erbB-3 expression could serve as an indicator of progression from premalignant to malignant transformation and of prognoses in patients with oral carcinoma, the authors examined the relation between the expression of c-erbB-3 protein and cell proliferation activity during the development of oral verrucous carcinoma (VC).

METHODS

Immunohistochemical techniques were used to evaluate c-erbB-3 protein and proliferative cell nuclear antigen (PCNA). Sixty-one samples (36 patients) of verrucous hyperplasia (VH), VC, and well differentiated squamous cell carcinoma arising from verrucous carcinoma (V-WSCC) in the oral mucosa were examined.

RESULTS

Normal human oral mucosa showed weak c-erbB-3 immunostaining, predominantly on the epithelial surface. In contrast, 7 (39%) of 18 VHs, 25 (84%) of 31 VCs, and all (100%) of 12 V-WSCCs demonstrated overexpression of c-erbB-3 protein with increased expression of PCNA in some premalignant epithelial cells and many tumor cells. This finding suggested the involvement of c-erbB-3 gene in the progression from VH to VC and V-WSCC.

CONCLUSIONS

Overexpression of c-erbB-3 protein correlated with increased PCNA labeling index, indicating that c-erbB-3 may contribute to malignant transformation and tumor growth. Further, patients with high expression of both c-erbB-3 and PCNA had a poor outcome. Study results suggested that c-erbB-3 expression was an index of malignancy during progression from VH to VC and V-WSCC and might have been involved in the outcome of oral carcinoma patients.

Expression of c-erbB3 protein in primary breast carcinomas

Expression of c-erbB3 protein was investigated in 104 primary breast carcinomas comprising nine comedo ductal carcinoma in situ (DCIS), 91 invasive ductal carcinomas and four invasive lobular carcinomas using two monoclonal antibodies, RTJ1 and RTJ2. Of the 91 invasive ductal carcinomas, seven contained the comedo DCIS component adjacent to the invasive component. An immunohistochemical technique was used to evaluate the association between expression of c-erbB3 and clinical parameters and tumour markers such as epidermal growth factor receptor (EGFR), c-erbB2, cathepsin-D and p53 in archival formalin-fixed paraffin-embedded tumour tissues. Our results indicated that RTJ1 and RTJ2 gave identical staining patterns and concordant results. It was found that the overexpression of c-erbB3 protein was observed in 67% (6/9) of comedo DCIS, 52% (44/84) of invasive ductal carcinomas, 71% (5/7) of carcinomas containing both the in situ and invasive lesions and 25% (1/4) of invasive lobular carcinomas. A significant relationship (P < 0.05) was observed between strong immunoreactivity of c-erbB3 protein and histological grade, EGFR and cathepsin-D, but not with expression of c-erbB2, p53, oestrogen receptor status, lymph node metastases or age of patient. However, we noted that a high percentage of oestrogen receptor-negative tumours (59%), lymph node-positive tumours (63%) and c-erbB2 (63%) were strongly positive for c-erbB3 protein. We have also documented that a high percentage of EGFR (67%), c-erbB2 (67%), p53 (75%) and cathepsin-D-positive DCIS (60%) were strongly positive for c-erbB3. These observations suggest that overexpression of c-erbB3 protein could play an important role in tumour progression from non-invasive to invasive and, also, that it may have the potential to be used as a marker for poor prognosis of breast cancer.

Expression of the c-erbB-4/HER4 protein and mRNA in normal human fetal and adult tissues and in a survey of nine solid tumour types

The c-erbB-4/HER4 receptor belongs to the family of the type I growth factor receptors. Mouse monoclonal antibodies have been raised to the cytoplasmic domain of the c-erbB-4 receptor and characterized; the antibody HFR-1 has been used to determine the pattern of expression of the c-erbB-4 protein immunohistochemically in formalin-fixed, paraffin-embedded adult and fetal tissues. The expression of c-erbB-4 mRNA was determined by using 35S-labelled riboprobes and tissue in situ hybridization. c-erbB-4 is widely expressed in many adult and fetal tissues, including the lining epithelia of the gastrointestinal, urinary, reproductive, and respiratory tracts, as well as the skin, skeletal muscle, circulatory, endocrine, and nervous systems. The developing brain and heart notably express high levels of this receptor. The pattern of c-erbB-4 protein expression is also reported in a survey of common solid human cancers. Loss of expression was noted in 40-80 per cent of adenocarcinomas and up to 100 per cent of squamous cell carcinomas, whereas overexpression was observed in about 10-20 per cent of adenocarcinomas and astrocytomas. In general, the pattern of c-erbB-4 expression in normal tissues and cancers suggests that it tends to be associated with the differentiated compartment.

Expression and functions of EGF, FGF and TGFbeta-growth-factor family members and their receptors in invasive human transitional-cell-carcinoma cells

Studies on epidermal-growth-factor-like-, fibroblast- and transforming growth factors suggested their implication in tumorigenesis involving effects on tumour-cell proliferation and migration. In human transitional-cell carcinomas (TCC), enhanced expression of TGF alpha and EGF receptors correlated with an aggressive phenotype. However, little is known about functions of these growth factors in invasive TCCs. In this study, we performed protein- and RNA-expression studies on a set of growth factors and their receptors on the newly established invasive human TCC cell line designated 1207. The data were correlated with functional proliferation and migration studies. Similar expression patterns of many cellular markers, growth factors and their receptors were noted both in the original TCC tissue and in its derivative cell line, indicating the relevance of this cell line to the investigation of growth factor functions on TCC cells. The proliferation induction by EGF, TGF alpha, amphiregulin, heregulin alpha, FGF-1 and FGF-7 correlated with the presence of EGF receptors, c-erbB4 and FGFR2 (IIIb), respectively. Amphiregulin and heregulin alpha induced the most proliferation. In conformity with the low expression of TGF beta receptors I and II, TGF beta1, barely inhibited proliferation, while TGF alpha induced invasion of 1207 cells into Matrigel. These data support the notion that notably EGF-like proteins mediate TCC growth and invasion through autocrine pathways which can be reinforced by loss of TGF beta1 regulation.