Aberrant expression of epidermal growth factor receptor in aural cholesteatoma

A monoclonal antibody recognizing an epitope of the external domain of the human epidermal growth factor (EGF) receptor was used in an alkaline phosphatase-antialkaline phosphatase (APAAP) technique to compare the distribution of this protein in normal human skin and aural cholesteatoma. EGF receptors appear to be highly expressed on the basal layer of the epidermis, in hair follicle apocrine sweat glands, and in the capillary system of normal skin. Cholesteatoma epithelium showed increased positive reactions in the suprabasal layers. A heterogeneity in the expression was found in different parts of the cholesteatoma. These results suggest the presence of an aberrant regulation and persistence of EGF receptors in cholesteatoma and confirm the hyperproliferative character of the cholesteatoma epithelium.     

Expression of epidermal growth factor, epidermal growth factor receptor and transforming growth factor-alpha in the human fetal inner ear

The expression of epidermal growth factor (EGF), EGF receptor and transforming growth factor (TGF)-alpha was analyzed in the human fetal inner ear using immuno-histochemical methods. EGF receptor was observed only in 9.5-week-old fetal vestibular epithelia. In 14- and 16-week-old fetuses, EGF receptor could not be detected. TGF-alpha was observed strongly in the 9- and 11-week-old vestibular epithelia, whereas only trace amounts were detectable in the 14- and 16-week-old vestibular epithelia. These findings suggest that EGF and TGF-alpha probably have a mitogenic effect in the sensory epithelia of the fetal inner ear, especially at early stages of development.     

表皮生长因子受体及血管内皮生长因子在喉乳头状瘤中的表达

目的探讨表皮生长因子受体（EGFR）和血管内皮生长因子（VEGF）在喉乳头状瘤（IJP）中的表达及意义。方法采用免疫组化二步法检测10例成人型喉乳头状瘤（ALP）、19例幼年型喉乳头状瘤（JLP）石蜡标本中EGFR、VEGF的表达与分布;并以10例声带息肉作为对照组。结果EGFR和VEGF在ALP、JLP组上皮层的表达水平明显高于对照组（P〈0．05）。EGFR在ALP、JLP表皮组织全层均有强阳性表达,VEGF呈现以基底层、棘层细胞显著表达,到颗粒层表达逐渐减弱的模式。VEGF在ALP、JLP和对照组间质的血管内皮细胞、炎症细胞、成纤维细胞中也有表达,但3组问VEGF的表达元显著统计学差异（P〉0．05）。JLP组上皮中VEGF的表达评分结果（7．133±0．061）比ALP组（6．934±0．041）高,两组比较有统计学意义（P〈0．05）。结论VEGF、EGFR在LP组织中的过度表达可能在LP的上皮细胞过度增生和血管大量形成中发挥重要作用,JLP比ALP具有更强的增殖活性。     

Overexpression of cyclooxygenase-2 in nasopharyngeal carcinoma and association with epidermal growth factor receptor expression

OBJECTIVES: To examine the association between cyclooxygenase-2 (COX-2) expression with epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), inducible nitric oxide synthase (iNOS), and latent membrane protein 1 (LMP-1) expression and with COX-2 promoter methylation status in primary nasopharyngeal cancer (NPC) tumors and to determine COX-2 promoter methylation status in NPC cell lines. DESIGN: Retrospective study. SETTING: Patients with NPC were referred to the Department of Otolaryngology-Head and Neck Surgery for treatment. PATIENTS: Formalin-fixed, paraffin-embedded NPC specimens from 42 patients were obtained. INTERVENTIONS: Immunohistochemical expression of COX-2, EGFR, VEGF, iNOS, and LMP-1 was performed in 42 NPC samples. COX-2 promoter methylation status was studied in 20 separate specimens and in 4 NPC cell lines. MAIN OUTCOME MEASURES: (1) COX-2, EGFR, VEGF, iNOS, and LMP-1 expression; and (2) COX-2 promotor methylation status. RESULTS: COX-2 was overexpressed in 79% of NPC specimens and was associated with EGFR status (P = .03) but not with LMP-1 or iNOS. In primary NPC tissue, methylation of the COX-2 promoter was seen in 4 of 7 COX-2-negative and 1 of 13 COX-2-positive immunohistochemical cases. COX-2 promoter methylation was found in the CNE-1 cell line. CONCLUSIONS: Nasopharyngeal cancer may be a useful target for selective COX-2 inhibition. The absence of promoter methylation may be a necessary component of COX-2 overexpression, and promoter methylation may be one of the mechanisms that regulate COX-2 expression.     

Upregulation of epidermal growth factor receptor 4 in oral leukoplakia

In the present study,we investigate the expression profile of the epidermal growth factor receptor family,which comprises EGFR/ ErbBl,HER2/ErbB2,HER3/ErbB3 and HER4/ErbB4 in oral leukoplakia(LP).The expression of four epidermal growth factor receptor (EGFR) family genes and their ligands were measured in LP tissues from 14 patients and compared with levels in 10 patients with oral lichen planus(OLP) and normal oral mucosa(NOM) from 14 healthy donors by real-time polymerase chain reaction(PCR) and immunohistochemistry.Synchronous mRNA coexpression of ErbBl,ErbB2,ErbB3and ErbB4 was detected in LP lesions.Out of the receptors,only ErbB4 mRNA and protein was more highly expressed in LP compared with NOM tissues.These were strongly expressed by epithelial keratinocytes in LP lesions,as shown by immunohistochemistry.Regarding the ligands,the mRNA of Neuregulin2 and 4 were more highly expressed in OLP compared with NOM tissues.Therefore,enhanced ErbB4 on the keratinocytes and synchronous modulation of EGFR family genes may contribute to the pathogenesis and carcinogenesis of LP.     

Northern印迹法检测喉鳞状细胞癌中表皮生长因子受体mRNA的表达

目的 :探讨喉部鳞状细胞癌的发病机制。方法 :采用Northern印迹法检测喉部鳞状细胞癌中表皮生长因子受体mRNA的表达。结果 :在喉部鳞状细胞癌中可见 5 80 0mRNA异常表达。结论 :喉部鳞状细胞癌的生物学行为与其 5 80 0mRNA介导异常表达密切相关。     

Expression and clinical significance of epidermal growth factor receptor and type 1 insulin-like growth factor receptor in nasopharyngeal carcinoma

OBJECTIVES: Epidermal growth factor (EGF) and type 1 insulin-like growth factor (IGF-1) receptors play an important role in the growth and apoptosis of nasopharyngeal carcinoma (NPC). They were separately found to be associated with prognosis in patients with NPC. To date, their expression correlation and clinicopathologic significance have never been specifically addressed in NPC. METHODS: Seventy-five patients with NPC and 21 noncancerous nasopharyngeal epithelial samples were accrued between 1998 and 2006 in a single hospital. The expressions of EGF and IGF-1 receptors were detected by immunohistochemical staining in the 75 NPC samples and the 21 noncancerous samples. Furthermore, the messenger RNA and protein expressions were assessed by real-time quantitative polymerase chain reaction and the Western blot technique, respectively, in NPC cell lines and normal nasopharyngeal epithelial cells. RESULTS: The 5-year survival rates, assessed by the Kaplan-Meier method, were 71.4% and 66.6% in the EGF and IGF-1 receptor protein-negative groups, respectively, whereas they were only 28.6% and 33.3% in the receptor protein-positive groups. The levels of these two proteins significantly correlated with each other, and the overexpression rates of EGF and IGF-1 receptors were 65.3% and 56% in nasopharyngeal samples, respectively. Furthermore, both protein expressions were significantly higher in NPC patients with cervical lymph node or distant metastasis than in NPC patients without lymph node or distant metastasis. Recurrence more often appears in cases positive for both proteins than in cases negative for both proteins. The expression levels of the receptor messenger RNA and proteins were higher in several NPC cell lines than in normal nasopharyngeal epithelial cells. CONCLUSIONS: These findings demonstrate that both receptor proteins may play an important role in the invasion, metastasis, and recurrence of NPC. Both receptors are valuable markers for assessing the prognosis of NPC. Their expression at such high frequencies provides the basis of combined targeted therapy with specific pharmacologic inhibitors to enhance the effects of radiotherapy and chemotherapy.     

Ryanodine receptor localisation in the mammalian cochlea: an ultrastructural study

Calcium-induced calcium release (CICR) in the mammalian cochlea has been suggested to enhance neurotransmitter release from inner hair cells and facilitate the efferent response in outer hair cells. Light microscopic evidence exists for the presence of ryanodine receptors in the organ of Corti but there is so far no information about their ultrastructural localisation. We have therefore used post-embedding immunogold labeling with antibodies that predominantly recognise ryanodine receptor isoforms 1 (RyR1) and 2 (RyR2) to investigate their distribution in rat cochleae. In inner hair cells, the highest levels of labeling were observed over an area of rough endoplasmic reticulum that lies in the cytoplasmic region beneath the nucleus; in outer hair cells, the cytoplasmic region above the nucleus displayed most labeling. Labeling was also associated with the subsurface cisternae adjacent to the lateral membranes of both types of hair cell, with the efferent terminals on the outer hair cells and was observed in adjacent supporting cells. Labeling in outer hair cells was significantly higher than that in inner hair cells or in the supporting cells. Our results support the presence of RyR1 in the cochlea but do not rule out the presence of other isoforms. CICR may be involved in the control of calcium levels in the base of the inner hair cells and supporting cells, and in the cholinergic efferent response and motile behaviour of the outer hair cells.     

Expression of epidermal growth factor receptor in laryngeal dysplasia and carcinoma

The immunoreactivity of epidermal growth factor receptor (EGFR) was studied in laryngeal biopsy specimens from 24 patients. The study comprised 5 cases of normal laryngeal mucosa, 5 cases of dysplasia, 7 cases of well differentiated squamous cell carcinoma, and 7 cases of poorly to moderately differentiated squamous cell carcinoma. EGFR was in general not expressed in normal and dysplastic epithelia, whilst all carcinomas showed a rather strong positive immunoreactivity. There was no significant difference in staining patterns between the well and poorly to moderately differentiated carcinomas. The results suggest that EGFR constitutes a component of neoplastic, but probably not preneoplastic, laryngeal disease. The study failed to reveal any difference in staining pattern between different types of laryngeal squamous cell carcinoma.     

Expression of epidermal growth factor receptor and its ligands in chronic sinusitis

The epidermal growth factor receptor (EGF-R) system plays a crucial role in mucus production in vitro and in rats. However, the role of the EGF-R system in humans is not known. We compared the localization of EGF-R and its ligands (epidermal growth factor and transforming growth factor alpha) in the epithelia of sinuses with chronic sinusitis and in those of healthy controls. Immunohistochemical techniques were employed to identify the presence of EGF-R and its ligands in the sinus mucosa. We found EGF-R in goblet cells, basal cells, and submucosal gland cells, but not in ciliated cells. Immunoreactivity for both epidermal growth factor and transforming growth factor alpha was found in the epithelial cells and inflammatory cells and in some submucosal gland cells. There was stronger staining of EGF-R and its ligand proteins in chronic sinusitis specimens than in controls. The interrelated localization of EGF-R and its ligands suggests a role in mucus production in the epithelium of the sinus mucosa.     

表皮生长因子受体在喉癌中的表达

为探讨表皮生长因子受体（enidermalgrowthfactorreceptor，EGFR）的表达在喉癌预后中的作用，运用免疫组化标记链霉菌素－生物素技术检测了60例喉癌和20例正常喉粘膜组织中EGFR的表达，发现20例正常喉粘膜组织全部为阴性，60例喉癌组织中44例出现EGFR阳性表达（阳性率73．3％）。EGFR的表达与喉爆发生部位、肿瘤分期和淋巴结转移之间无明显相关性，而与组织分化程度，患者生存率之间显著相关。低分化喉癌EGFR的表达较中、高度分化喉癌明显增高（P＜0．05）。具有EGFR阳性表达的喉癌患者3年生存率明显低于阴性患者（P＜0．01）。结果提示，EGFR的表达在喉癌的发生发展中起一定作用，并可作为判断喉癌生物行为和预后的一个参考指标。     

Inhibition of epidermal growth factor receptor signaling decreases p63 expression in head and neck squamous carcinoma cells

OBJECTIVES/HYPOTHESIS: Both the epidermal growth factor receptor (EGFR) and the p53 homologue p63 are overexpressed in a significant number of cases of head and neck squamous cell carcinoma (HNSCC). Epidermal growth factor receptor and p63 both possess oncogenic properties, including the potential to increase cell proliferation and antagonize apoptosis. ZD1839 ("Iressa") is an adenosine triphosphate-competitive inhibitor specific to the EGFR tyrosine kinase currently under evaluation as a chemotherapeutic agent in HNSCC. The objective was to investigate whether p63 expression is decreased after treatment of HNSCC cells with ZD1839. Downregulation of p63 by ZD1839 would identify a potential molecular relationship between EGFR signaling and p63 and could provide insight into the mechanism of action of ZD1839. STUDY DESIGN: In vitro examination of p63 expression after ZD1839 treatment. METHODS: A human HNSCC cell line, SCC-012, was treated with varying doses of ZD1839. p63 protein and messenger RNA levels were analyzed by Western and Northern blot analyses. The effect of ZD1839 on SCC-012 cell cycle was analyzed by flow cytometric analysis. RESULTS: In SCC-012 cells there was a dose-dependent decrease in p63 protein and messenger RNA levels over the course of ZD1839 treatment. Levels of phosphorylated MAPK decreased and p27KIP-1 levels increased after ZD1839 treatment. ZD1839 treatment induced a twofold increase in G1-phase cells and a 3.5-fold decrease in S-phase cells consistent with growth arrest. CONCLUSION: ZD1839 downregulates p63 expression at the messenger RNA level, suggesting that p63 is a downstream target of EGFR signaling.     

Immunohistochemical localization of nerve growth factor receptor in the cochlea and in the brainstem of the perinatal rat.

Nerve growth factor receptor (NGF-R) localization was studied immunohistochemically in the cochlea and in the brainstem of the perinatal rat, using a specific monoclonal antibody directed against the rat NGF-R. In the cochlea, NGF-R immunoreactivity is positive during the whole perinatal period studied, and is located at the hair cell level, in fibers that reach the organ of Corti, in the intraganglionic spiral bundle and in some small bundles of fibers in the auditory nerve. In the brainstem, NGF-R is detected in auditory structures such as the ventral cochlear nucleus, the superior olivary complex, the nuclei of the trapezoid body and the trapezoid body. Many auditory structures labelled by the NGF-R antibody are implicated in the efferent cochlear innervation. These results suggest that NGF could be implicated in interactions between auditory receptors and efferent innervation of the developing cochlea. This coincides with findings on the immunohistochemical localization of NGF-like protein in the organ of Corti of the developing rat. Moreover, these observations could be related to an early prenatal development of auditory efferent innervation.     

Immunohistochemical detection of epidermal growth factor receptor in laryngeal squamous cell carcinomas.

Laryngeal squamous cell carcinomas from 15 consecutive preoperatively irradiated patients were investigated for the expression of epidermal growth factor receptor (EGF receptor). The study was performed on frozen sections by means of the 5-layer APAAP technique employing an antibody recognizing the extracellular part of the EGF receptor. In sections from 9 of the patients with laryngeal squamous cell carcinoma, normal differentiated epithelia were included. Sections from 6 of these patients, in addition, contained dysplastic epithelia. Expression of EGF receptor-like material was demonstrated in the basal cell layer of normally differentiated laryngeal epithelial and in dysplastic epithelia. Fourteen of the squamous cell carcinomas proved EGF receptor positive. Nearly all cells in the poorly differentiated carcinomas showed positive staining with the antibodies. In moderately to well differentiated carcinomas a reduction in the extent of staining was seen in certain areas. Especially for the epithelial pearls, the staining reaction was localized to the undifferentiated cells in the periphery. This finding corresponds to the staining pattern observed in the basal cell layers of normal epithelial. The present investigation confirms the expression of EGF receptor-like material in normal laryngeal epithelial, dysplastic epithelial and squamous cell carcinoma. The staining pattern was similar to that observed in oral squamous cell carcinomas, predominantly varying inversely with cellular differentiation.