Quantification of Tyrosine Hydroxylase and ErbB4 in the Locus Coeruleus of Mood Disorder Patients Using a Multispectral Method to Prevent Interference with Immunocytochemical Signals by Neuromelanin / 神经科学通报·英文版

The locus coeruleus (LC) has been studied in major depressive disorder (MDD) and bipolar disorder (BD). A major problem of immunocytochemical studies in the human LC is interference with the staining of the immunocytochemical end-product by the omnipresent natural brown pigment neuromelanin. Here, we used a multispectral method to untangle the two colors: blue immunocytochemical staining and brown neuromelanin. We found significantly increased tyrosine hydroxylase (TH) in the LC of MDD patients-thus validating the method-but not in BD patients, and we did not find significant changes in the receptor tyrosine-protein kinase ErbB4 in the LC in MDD or BD patients. We observed clear co-localization of ErbB4, TH, and neuromelanin in the LC neurons. The different stress-related molecular changes in the LC may contribute to the different clinical symptoms in MDD and BD.

Research progress of neuregulin 4 biological function / 生理学报

Neuregulin 4 (NRG4) is a kind of protein containing epidermal growth factor (EGF)-like domains, mainly expressed and secreted by brown adipocytes. It specifically activates EGF receptor ErbB4 (v-erb-b2 avian erythroblastic leukemia viral oncogene homolog 4) to stimulate cell proliferation, inhibit apoptosis and improve energy metabolism of cells. Increasing evidence has shown that NRG4 plays an important role in epithelial cell-related diseases, cardiovascular diseases, tumors and glycolipid metabolic diseases, and therefore it could be a potential therapeutic target of some diseases.

miR-520a regulates ErbB4 expression and suppresses proliferation and invasion of esophageal squamous cell carcinoma / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the role of miR-520a in regulation ErbB4 expression and the biological behavior of esophageal squamous cell carcinoma (ESCC).</p><p><b>METHODS</b>The role of miR-520a in regulating the expression of ErbB4 was investigated by Western blotting and luciferase reporter assay system. The effect of miR-520a on the proliferation and invasion of ESCC cells was detected by MTT and Transwell invasion assay, respectively.</p><p><b>RESULTS</b>Western blotting and luciferase reporter assay revealed that miR-520a down-regulated the expression of ErbB4 in vitro. miR-520a significantly inhibited the proliferation and suppressed the invasion of ESCC cell line Eca109.</p><p><b>CONCLUSION</b>miR-520a regulates the expression of ErbB4 and suppresses the proliferation and invasion of ESCC cells in vitro, suggesting its role as a tumor suppressor.</p>

The absence of the ERBB4 hotspot mutations in melanomas in patients from southern China / 癌症

V-erb-a erythroblastic leukemia viral oncogene homolog 4 (ERBB4) has been reported to be somatically mutated in 19% of melanoma cases. To investigate the prevalence of ERBB4 mutations in melanoma patients from southern China, we analyzed 117 formalin-fixed, paraffin-embedded melanoma samples archived in the Sun Yat-sen University Cancer Center. A matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) platform was used to screen for mutations. No ERBB4 hotspot mutations were detected. Our results indicate that ERBB4 mutations may play a limited role in melanomas in China; therefore, targeting the ERBB4 mutation in melanoma patients from southern China may not be a promising strategy.

Clinical significance of human epidermal growth factor receptor family molecules expression in gastric cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To study the association of human epidermal growth factor receptor family molecules expression in gastric cancer tissues with the prognosis of patients with gastric cancer.</p><p><b>METHODS</b>Clinical data of 161 patients with gastric cancer undergoing gastrectomy in Jiangsu Cancer Hospital between January 2006 and January 2007 were analyzed retrospectively. The expression of HER1, HER2, HER3 and HER4 was detected by immunohistochemistry. Association of the expression of HER family with the prognosis of patients was examined. Kaplan-Meier method was used to analyze the survival.</p><p><b>RESULTS</b>High expression rates of HER1, HER2, HER3 and HER4 were 46.0% (74/161), 10.6% (17/161),55.9% (90/161) and 68.3% (110/161) respectively. Univariate analysis revealed that high expression of HER3 was associated with tumor invasion depth, lymph node metastasis, stage, neurovascular invasion, and overall 4-year survival. High expression of HER4 was associated with tumor distant metastasis and stage. High co-expression of HER2 and HER3 was associated with overall 4-year survival (P=0.023). Multivariate analysis revealed that high expression of HER3 and stage were prognostic independent factors.</p><p><b>CONCLUSION</b>Up-regulated expression of HER3 is associated with the poor prognosis in gastric cancer patients.</p>

Upregulation of epidermal growth factor receptor 4 in oral leukoplakia / 国际口腔科学杂志·英文版

In the present study, we investigate the expression profile of the epidermal growth factor receptor family, which comprises EGFR/ErbB1, 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 ErbB1, ErbB2, ErbB3 and 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.

Endogenous neuregulin-1 expression in the anterior pituitary of female Wistar-Furth rats during the estrous cycle / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the changes in endogenous neuregulin-1 (Nrg1) expression in the anterior pituitary of female Wistar-Furth rats in different phases of the estrous cycle.</p><p><b>METHODS</b>Female Wistar-Furth rats during estrous cycles were used. RT-PCR was employed to study the changes in the expression of Nrg1 isoforms and their cognate receptors ErbB-2 and ErbB-4 in the anterior pituitary in different phases of the estrous cycle. Western blotting was used to detect Nrg1 expression at the protein level. Immunofluorescence staining was used to identify hypophyseal cells expressing Nrg1 and observe the localization and distribution of Nrg1 and functional phosphorylation of ErbB-4. The co-expression of Nrg1 and ErbB-4 in the anterior pituitary of Rhesus monkey was also investigated.</p><p><b>RESULTS</b>Some of the Nrg1 isoforms, especially type III Nrg1s, were expressed at a higher level during the estrous cycle I (E1) and estrous cycle II (E2), a result consistent with that of Western blotting for samples of the anterior pituitaries collected at these phases. Immunofluorescence staining identified the gonadotrophs as the main source of Nrg1, and showed an extensive distribution of Nrg1 in the anterior pituitary in E1 and E2 phases accompanied by apparent phosphorylated activation of ErbB-4. Adjacent distribution of Nrg1- and ErbB-4-positive cells was also observed in the anterior pituitary of male Rhesus monkeys.</p><p><b>CONCLUSION</b>Our results provide evidence for the expression of multiple Nrg1 isoforms and the presence of Nrg1/ErbB-4 signaling in the anterior pituitary of female Wistar-Furth rats. This signaling demonstrates an estrous cycle phase-related pattern. Additionally, Nrg1/ErbB-4-based juxtacrine signaling may exist in the anterior pituitary of male non-human primate.</p>

Neuregulin-1 preconditioning protects the heart against ischemia/reperfusion injury through a PI3K/Akt-dependent mechanism / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Neuregulin-1 (NRG-1), the ligand of the myocardial ErbB receptor, is a protein mediator with regulatory actions in the heart. This study investigated whether NRG-1 preconditioning has protective effects on myocardial ischemia/reperfusion (I/R) injury and its potential mechanism.</p><p><b>METHODS</b>We worked with an in vivo rat model with induced myocardial ischemia (45 minutes) followed by reperfusion (3 hours). NRG-1 message was detected in the heart using RT-PCR and the protein levels of NRG-1 and ErbB4 were detected by Western blotting analysis. Infarct size was assessed using the staining agent triphenyltetrazolium chloride and cardiac function was continuously monitored. The levels of creatine kinase and lactate dehydrogenase in plasma were analyzed to assess the degree of cardiac injury. The extent of cardiac apoptosis was evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay and by Western blotting analysis of cleaved caspase-3. We examined the phosphorylation of Akt in the myocardium and the effect of PI3K/Akt inhibition on NRG-1-induced cardioprotection.</p><p><b>RESULTS</b>Transcription and expression of NRG-1 and phosphorylation of its ErbB4 receptor were significantly upregulated in the I/R hearts. NRG-1 pretreatment reduced the infarct size following cardiac I/R in a concentration-dependent manner with an optimal concentration of 4 µg/kg in vivo. NRG-1 pretreatment with 4 µg/kg, i.v. markedly reduced the plasma creatine kinase and lactate dehydrogenase levels. Pretreatment with NRG-1 also significantly reduced the percentage of TUNEL positive myocytes and the level of cleaved caspase-3 in the I/R hearts. Pretreatment with NRG-1 significantly increased phosphorylation of Akt following I/R. Furthermore, the cardioprotective effect limiting the infarct size that was induced by NRG-1 was abolished by co-administration of the PI3K inhibitor LY294002.</p><p><b>CONCLUSIONS</b>The concentration of NRG-1, a new autacoid, was rapidly upregulated after myocardial I/R. NRG-1 preconditioning has cardioprotective effects against I/R injury through a PI3K/Akt-dependent mechanism in vivo.</p>

The correlation between ketamine-induced schizophrenia-like signs in mice and the expressions of NRG1, ErbB4 mRNA / 法医学杂志

OBJECTIVE@#To explore the correlation between signs similar to schizophrenia in mice after ketamine administration and the expressions of NRG1 and ErbB4 mRNA in order to explain the possible pathogenesis of schizophrenia.@*METHODS@#Fifty KM mice were randomly divided into 5 groups which were administered intraperitoneally with saline, clozapine and different dosages ketamine. The ketamine groups were administered intraperitoneally with low dosage (25 mg/kg), middle dosage (50 mg/kg) and high dosage (100 mg/kg) one time every day for 7 days. After administration of 100 mg/kg ketamine for 7 days, the clozapine group was introgastrically administered 20 mg/kg with clozapine one time every day for 7 days. The pathological changes of hippocampus neurons were observed by HE stain. The expressions of the NRG1 and ErbB4 mRNA in hippocampus were detected by reverse transcriptase polymerase chain reaction (RT-PCR).@*RESULTS@#In the group with high dosage of ketamine, the levels of NRG1 and ErbB4 mRNA were significantly lower than that of the group with saline.@*CONCLUSION@#Ketamine may induce signs similar to schizophrenia in KM mice. The mechanism may be involved in the reduction of NRG1 and ErbB4 mRNA expression.

Changes of ErbB receptors mRNA expression in left ventricle of myocardial infarction / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the changes of ErbB receptors mRNA expression in left ventricle of myocardial infarction and its mechanism.</p><p><b>METHODS</b>Myocardial infarction was induced by ligation of the left anterior descending coronary artery in male Sprague Dawley(SD) rats. After 1 month, the rats were sacrificed and mRNA was extracted from the left ventricle. mRNA was also extracted from ventricular myocytes of neonatal SD rats which were cultured under serum deprivation and hypoxia for 5 d. Expression of ErbB receptors mRNA were detected by real-time quantitative PCR.</p><p><b>RESULT</b>The mRNA expression of ErbB2 and ErbB4 receptors was significantly down-regulated in the left ventricle of myocardial infarction compared with the normal left ventricle; in contrast, there were no changes in mRNA expression of ErbB3. Serum deprivation and hypoxia in vitro caused significant down-regulation of the mRNA expression of ErbB2 and ErbB4 receptors, but the mRNA expression of ErbB3 was not changed.</p><p><b>CONCLUSION</b>Expression of ErbB2 and ErbB4 receptors mRNA is down-regulated in myocardial infarction, which may results from the hypoxia, deprivation of nutrients and cytokines.</p>

Expression and significance of ErbB3 and ErbB4 in patients with laryngeal squamous cell carcinomas / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To explore expression of ErbB3 and ErbB4 genes in laryngeal squamous cell carcinomas and their relation with the biological and clinicopathological parameters.@*METHOD@#Expression of ErbB3 and ErbB4 mRNA in 36 cases of laryngeal carcinomas and normal mucosa of incisal margin, 11 cases of benign proliferative lesions were examined by reverse transcription polymerase chain reaction (RT-PCR).@*RESULT@#In laryngeal carcinomas and benign proliferative lesions, over-expressive positive ratios of ErbB3 were 66.7%, 18.2% respectively (P 0.05). Differences of expressive level of ErbB3 and ErbB4 were not significant between laryngeal carcinoma and normal mucous of incisal margin (P > 0.05). In addition, expressive level of ErbB3 and ErbB4 were not associated with diversity of clinical pathologic characters (P > 0.05).@*CONCLUSION@#ErbB3 and ErbB4 genes play different role in carcinogenesis and development, and relate to the reoccurrence of carcinoma.

The regulation of EKI-785 to the growth of U937 cell line / 中华肿瘤杂志

<p><b>OBJECTIVE</b>The aim of this study was to explore the expression of erbBs in U937, an acute monocyte leukemia cell line, and their impact on the growth of this cell line.</p><p><b>METHODS</b>Expression of erbBs was detected by RT-PCR and expression of erbB2 at protein level by Western blot. After U937 cells was treated with EKI-785, an irreversible specific inhibitor of erbBs, the growth was assessed by MTT and growth curve, apoptosis was detected by Annexin V-FITC Apoptosis Detection Kit, and signal pathway was detected by Western blot.</p><p><b>RESULTS</b>erbB2-4 were expressed in U937 cell line, but not erbB1. Especially, protein of erbB2 was expressed in this cell line. After treating with EKI-785, the growth of U937 cells was inhibited and early apoptosis was induced. Moreover, the Ras/MAPK and the PI3K/Akt signaling pathways were all blocked.</p><p><b>CONCLUSION</b>erbBs may play key roles in the development of some leukemia. Therefore, erbBs may become new targets of treatment to leukemia, and EKI-785 has a potency of clinic use to leukemia.</p>

Relation between c-erbB1, c-erbB2, MAPK expression and resistance to tamoxifen in breast cancer cells in vitro / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the growth regulation pathway and the mechanism of acquired resistance to tamoxifen (TAM) in breast cancer cells.</p><p><b>METHODS</b>TAM was used to induce wild-type MCF-7 human breast cancer cell line and establish a tamoxifen-resistant (TAM-R) cell line. RT-PCR, Western blot and immuocytochemical techniques were used to detect and compare mRNA and protein of c-erbB1, cerbB2, c-erbB3, c-erbB4 in wild-type MCF-7 and TAM-R MCF-7 cell lines.</p><p><b>RESULTS</b>Compared with wild-type MCF-7 cells, the mRNA of c-erbB1 increased 6 times (P < 0.05) and the protein 3 times higher (P < 0.05), and the mRNA of c-erbB2 increased 3 times (P < 0.05) and the protein 1.5 times higher (P < 0.05) in TAM-R MCF-7 cells. However, comparable levels of c-erbB3 mRNA and protein were expressed in both cell lines. c-erbB4 could not be detected. Under basic conditions, phosphorylated c-erbB1/c-erbB2 and c-erbB1/c-erbB3 heterodimers but not c-erbB2/c-erbB3 receptor heterodimers were detected in TAM-R cells in association with increased level of phosphorylated MAPK.</p><p><b>CONCLUSION</b>Our findings demonstrated that the development of TAM-resistance in MCF-7 cells is related with the autocrine release and action of an c-erbB1-specific ligand inducing preferential c-erbB1/c-erbB2 dimerization and downstream activation of the MAPK pathway.</p>