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)

We studied the expression of epidermal growth factor (EGF) receptor protein and messenger RNA (mRNA) in human fallopian tubes at three stages of the menstrual cycle: early follicular (n = 3), late follicular (n = 3) and luteal (n = 3). Immunohistochemical studies in the ampullary portion of the tubes showed that specific staining was localized to the epithelium and the vascular endothelium. Staining of the epithelium was intense at the late follicular and luteal stages, while it was weak at the early follicular stage. 125I-EGF binding study in the tubal plasma membranes revealed a class of high-affinity EGF receptors. Although dissociation constants were similar between the stages, numbers of binding sites at the late follicular and luteal stages were significantly (P < 0.01) greater than those at the early follicular stage. Western blotting showed that tubal plasma membranes contain M(r) 170,000 EGF receptor protein. The amounts were significantly (P < 0.01, n = 3) greater at the late follicular and luteal stages than those at the early follicular stage. Reverse transcription and polymerase chain reaction (RT-PCR) revealed that EGF receptor mRNA was expressed in all the 9 RNA samples (n = 3 for each stage) from the tubal ampullary portion. The amounts were significantly (P < 0.01, n = 3) greater at the late follicular and luteal stages than those at the early follicular stage (by a competitive PCR). Increase in the amounts of EGF receptor protein and mRNA occurred in association with an increase in serum oestradiol but not progesterone levels. Next we examined whether EGF receptor and its ligands (EGF and transforming growth factor alpha) are directly induced by oestrogen. We found that specific staining for EGF receptor and its ligands in the tubal epithelium was detected (by immunohistochemistry) in postmenopausal women with oestrogen replacement (n = 3), but not in subjects without oestrogen replacement (n = 3). These results suggested that EGF receptors in the human tubal epithelium are expressed in relation to specific stages of the menstrual cycle and that the expression may be induced by oestrogen.
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PMID:Menstrual cycle specific expression of epidermal growth factor receptors in human fallopian tube epithelium. 854 26

Reactive oxygen species (ROS) function as intracellular signaling molecules in a diverse range of biological processes. However, it is unclear how freely diffusible ROS dictate specific cellular responses. In this study, we demonstrate that nicotinamide adenine dinucleotide phosphate reduced oxidase 4 (Nox4), a major Nox isoform expressed in nonphagocytic cells, including vascular endothelium, is localized to the endoplasmic reticulum (ER). ER localization of Nox4 is critical for the regulation of protein tyrosine phosphatase (PTP) 1B, also an ER resident, through redox-mediated signaling. Nox4-mediated oxidation and inactivation of PTP1B in the ER serves as a regulatory switch for epidermal growth factor (EGF) receptor trafficking and specifically acts to terminate EGF signaling. Consistent with this notion, PTP1B oxidation could also be modulated by ER targeting of antioxidant enzymes but not their untargeted counterparts. These data indicate that the specificity of intracellular ROS-mediated signal transduction may be modulated by the localization of Nox isoforms within specific subcellular compartments.
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PMID:Regulation of ROS signal transduction by NADPH oxidase 4 localization. 1857 11