{"title":"Exposure to Hypoxic Conditions Up-regulates HER2 in Breast Cancer Cell Lines.","authors":"Nobuyasu Suganuma, Nao Saito, Mio Yasukawa, Takashi Yamanaka, Toshinari Yamashita, Yohei Miyagi, Aya Saito, Daisuke Hoshino","doi":"10.21873/anticanres.17344","DOIUrl":null,"url":null,"abstract":"<p><strong>Background/aim: </strong>Tissue specimen quality is becoming increasingly important for basic research and routine clinical results. Warm ischemia time (WIT) affects human epidermal growth factor receptor 2 (HER2) immunohistochemistry (IHC) scores. However, the role of WIT on HER2 modulation remains unclear. We hypothesized that the WIT-mediated increase in HER2 IHC scores was caused by hypoxia. Therefore, this study aimed to determine the mechanism by which WIT mediates the increase in HER2.</p><p><strong>Materials and methods: </strong>HER2 mRNA expression was measured in 4T1, SKBR3, and HCC1954 breast cancer cell lines using real-time PCR following hypoxia exposure. The membrane proteins were isolated and extracted using the Mem-PER™ Plus Membrane Protein Extraction Kit (Thermo Fisher Scientific, Waltham, MA, USA) or evaluated through non-permeabilized immunofluorescent analysis.</p><p><strong>Results: </strong>Hypoxic conditions up-regulated GLUT1 mRNA expression but not HER2 expression. The HER2 membrane protein fraction increased in response to hypoxic conditions. Nonpermeabilized immunofluorescence analysis showed that membrane-bound HER2 was also promoted under hypoxic conditions.</p><p><strong>Conclusion: </strong>HER2 is not regulated at the mRNA level; however, the level of membrane-bound HER2 increases in response to hypoxia.</p>","PeriodicalId":8072,"journal":{"name":"Anticancer research","volume":"44 12","pages":"5187-5192"},"PeriodicalIF":1.6000,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Anticancer research","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.21873/anticanres.17344","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"ONCOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Background/aim: Tissue specimen quality is becoming increasingly important for basic research and routine clinical results. Warm ischemia time (WIT) affects human epidermal growth factor receptor 2 (HER2) immunohistochemistry (IHC) scores. However, the role of WIT on HER2 modulation remains unclear. We hypothesized that the WIT-mediated increase in HER2 IHC scores was caused by hypoxia. Therefore, this study aimed to determine the mechanism by which WIT mediates the increase in HER2.
Materials and methods: HER2 mRNA expression was measured in 4T1, SKBR3, and HCC1954 breast cancer cell lines using real-time PCR following hypoxia exposure. The membrane proteins were isolated and extracted using the Mem-PER™ Plus Membrane Protein Extraction Kit (Thermo Fisher Scientific, Waltham, MA, USA) or evaluated through non-permeabilized immunofluorescent analysis.
Results: Hypoxic conditions up-regulated GLUT1 mRNA expression but not HER2 expression. The HER2 membrane protein fraction increased in response to hypoxic conditions. Nonpermeabilized immunofluorescence analysis showed that membrane-bound HER2 was also promoted under hypoxic conditions.
Conclusion: HER2 is not regulated at the mRNA level; however, the level of membrane-bound HER2 increases in response to hypoxia.
期刊介绍:
ANTICANCER RESEARCH is an independent international peer-reviewed journal devoted to the rapid publication of high quality original articles and reviews on all aspects of experimental and clinical oncology. Prompt evaluation of all submitted articles in confidence and rapid publication within 1-2 months of acceptance are guaranteed.
ANTICANCER RESEARCH was established in 1981 and is published monthly (bimonthly until the end of 2008). Each annual volume contains twelve issues and index. Each issue may be divided into three parts (A: Reviews, B: Experimental studies, and C: Clinical and Epidemiological studies).
Special issues, presenting the proceedings of meetings or groups of papers on topics of significant progress, will also be included in each volume. There is no limitation to the number of pages per issue.