Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04626 (erbB-2)
 5,251 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Laryngeal papillomas are benign epithelial tumors caused by human papillomaviruses. These tumors are characterized by hyperplasia of the spinous layer and abnormal differentiation. Many tumor cell lines over-express the epidermal growth factor (EGF) receptor on their surface, and EGF regulates normal cell growth. We have asked about the relationship of the EGF receptor and EGF response in laryngeal papilloma cells. Papilloma cells showed markedly greater immunohistochemical staining for the EGF receptor, compared to uninfected cells. Both cell types showed a 2-3-fold increase in nuclei incorporating bromodeoxyuridine when EGF was present. Removal of EGF from papilloma cells cultured on collagen rafts permitted normal stratification and differentiation, as determined by synthesis of keratin 13. Inclusion of EGF induced abnormal differentiation with minimal expression of keratin 13. Uninfected laryngeal cells cultured on rafts in the presence of EGF synthesize keratin 13 in all suprabasal cells. EGF reduced both human papillomavirus RNA levels in the papilloma cells and expression of a reporter gene linked to the human papillomavirus 11 enhancers and E6 promoter in uninfected cells. These results suggest that the phenotype of papillomas is induced, in part, by EGF binding to the abundant EGF receptors.
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PMID:Laryngeal papilloma cells have high levels of epidermal growth factor receptor and respond to epidermal growth factor by a decrease in epithelial differentiation. 767 53

To directly compare the expression patterns of different proteins known to be altered during mouse skin carcinogenesis, serial sections of normal and hyperplastic skin and tumors from various stages of 7,12-dimethylbenz[a]anthracene-initiated, 12-O-tetradecanoylphorbol-13-acetate-promoted female SENCAR mice were examined by immunohistochemistry. In untreated, normal mouse skin, keratin 1 (K1) and transforming growth factor-beta1 (TGFbeta1) were strongly expressed in the suprabasal layers, whereas integrin alpha6beta4 was expressed only in basal cells and only moderate staining for transforming growth factor-alpha (TGFalpha) was seen. In hyperplastic skin, TGFalpha expression became stronger, whereas expression of another epidermal growth factor (EGF) receptor ligand, heparin-binding EGF-like growth factor (HB-EGF), was strongly induced in all epidermal layers from no expression in normal skin. Likewise, the gap-junctional protein connexin 26 (Cx26) became highly expressed in the differentiated granular layers of hyperplastic skin relative to undetectable expression in normal skin. Expression of cyclin D1 in the proliferative cell compartment was seen in all benign and malignant tumors but not in hyperplastic skin. Beginning with very early papillomas (after 10 wk of promotion), expression of alpha6beta4 in suprabasal cells and small, focal staining for keratin 13 (K13) were seen in some tumors. Later (after 20-30 wk), focal areas of gamma-glutamyl transpeptidase (GGT) activity appeared in a few papillomas, whereas TGFbeta1 expression began to decrease. Cx26 and TGFalpha staining became patchier in some late-stage papillomas (30-40 wk), whereas suprabasal alpha6beta4, K13, and GGT expression progressively increased and K1 expression decreased. Finally, in squamous cell carcinomas (SCCs), there was an almost complete loss of K1 and a further decline in TGFalpha, HB-EGF, TGFbeta1, and Cx26 expression. On the other hand, almost all SCCs showed suprabasal staining for alpha6beta4 and widespread cyclin D1 and K13 expression, whereas only about half showed positive focal staining for GGT activity.
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PMID:Changes in protein expression during multistage mouse skin carcinogenesis. 932 43