The epidermal growth factor receptor (EGFR) has been implicated in the regulation of wound healing. In order to directly evaluate the role of endogenous EGFR in cutaneous incisional wound healing, we examined EGFR null- and wild-type skin after injury. By 5 d after wounding, re-epithelialization was complete in all EGFR wild-type wounds, but in only 40% of EGFR null wounds. Delayed wound closure in EGFR null skin was accompanied by an increase in edema, longer lasting and more prominent eschar, and increased distance between apposing wound edges. EGFR altered neutrophil and mast cell infiltration, and enhanced angiogenesis. EGFR enhanced epithelial proliferation during the first 3 d following injury, although proliferation was greater in EGFR null wounds at 5 d. Although migration was decreased in EGFR null keratinocytes cultured with standard medium or in medium supplemented with transforming growth factor-alpha when compared with controls, the addition of the wound-associated motogen keratinocyte growth factor eliminated the differences between genotypes. Epithelial migration into the wound was decreased in EGFR null skin, suggesting that both EGFR-dependent and -independent mechanisms regulate migration during wound healing. These data demonstrate that EGFR regulates multiple facets of cutaneous wound healing, including inflammation, wound contraction, proliferation, migration, and angiogenesis.
BACKGROUND:The current study was performed to determine the impact of polysomy 17 on the interpretation of HER2 testing of invasive breast carcinomas using fluorescent in situ hybridization methods. Current American Society of Clinical Oncology/College of American Pathologists guidelines define HER2-positive tumors as those with >6 HER2 genes per nucleus or those with HER2/CEP17 (chromosome 17) ratio >2.2. These guidelines are potentially contradictory in tumors with polysomy of chromosome 17. METHODS: Seventy-two breast carcinoma cases with reported polysomy of chromosome 17 (3 CEP17 signals on average) by fluorescent in situ hybridization were identified, and the corresponding HER2 immunohistochemistry was obtained. The HER2 status of the archived samples was reviewed, and the tumors were recategorized according to the 2007 American Society of Clinical Oncology/College of American Pathologists guidelines. RESULTS: The average CEP17 copy number for the group was 4.5 (range, 3.0-10.4). Thirty-three (45.8%) cases had >6 copies of HER2 per nucleus. Twenty-one cases (29.2%) qualified as HER2 gene amplified using the HER2/CEP17 ratio (>2.2) guideline. All these cases had >6 HER2 signals, which represented 63.6% of all cases with >6 HER2 signals. HER2 protein expression showed significant positive correlations with both HER2 gene copy number and HER2/CEP17 ratio (P < .01, r s ¼ 0.56 and 0.64, respectively). CONCLUSIONS: Increased CEP17 signals detected in invasive breast carcinomas may lead to discordant interpretation of gene amplification in a significant proportion of the cases, depending on which criterion (ratio vs absolute number) is used for interpretation. However, increased gene dosage (>6 HER2 genes or HER2/CEP17 ratio >2.2), regardless of the evaluation method, is positively correlated with HER2 protein expression. Cancer 2011;117:48-53.
This report describes the brain autopsy of a boy who at age 4(1/2) years experienced an episode of fulminant Haemophilus influenzae type b bacterial meningitis, resulting in massive brain destruction and the clinical signs of brain death. However, medical intervention maintained him for an additional two decades. Subsequent autopsy revealed a calcified intracranial spherical structure weighing 750 g and consisting of a calcified shell containing grumous material and cystic spaces with no recognizable neural elements grossly or microscopically. This case represents an example of long survival of brain death with a living body.
The epidermal growth factor receptor (EGFR) is activated in cutaneous keratinocytes upon ultraviolet (UV) exposure and has been implicated in ultraviolet-(UV-)induced inflammation and skin tumorigenesis. Egfr mutant mice and EGFR inhibitors were used to investigate the hypothesis that EGFR activation augments inflammation following UV irradiation. Topical treatment of mouse skin with the EGFR inhibitor AG1478 before UV exposure suppressed UV-induced erythema, edema, mast cell infiltration, and neutrophil infiltration. Genetic ablation of Egfr and EGFR inhibition by AG1478 also suppressed the increase in the proinflammatory cytokines tumor necrosis factor α (TNF-α), interleukin-1α, KC (murine IL-8), and cyclooxygenase-2 (COX-2) after UV exposure of cultured keratinocytes. Finally, genetic ablation of inhibition of EGFR in cultured keratinocytes decreased p38 activation after UV, while inhibition of p38 kinase reduced COX-2 expression after UV. These data demonstrate that EGFR regulates multiple aspects of UV-induced inflammation and suggest activation of p38 kinase leading to increased COX-2 and cytokine expression as one mechanism through which it acts.
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