Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

TRANSCRIPTIONAL EFFECTS OF INHIBITING EGFR IN KERATINOCYTES

ABSTRACT: EGFR activation is important in human epithelial malignancies, including cutaneous squamous cell carcinoma, lung, colon, pancreatic and other cancers. Therapies targeting EGFR are currently used to treat such cancers, but one significant drawback to EGFR inhibitor therapies is the associated skin toxicity. This toxicity usually presents as papular or pustular folliculitis, dry skin with pruritus and hair and nails abnormalities. The side effects often limit the usefulness of EGFR inhibitors in cancer treatment. The transcriptional changes caused by EGFR inhibition in epidermal keratinocytes have not been extensively explored. To define the transcriptional changes caused by inhibition of EGFR in primary human epidermal keratinocytes, we treated these cells with Tyrphostin and compared treated and control cultures in parallel, using Affymetrix microarrays. Using metaanalysis approaches, we integrated the observed changes with a large set of already existing data on transcriptional profiling in epidermal keratinocytes. We found that EGFR inhibition suppresses expression of genes associated with keratinocyte proliferation, attachment and motility. Apoptosis is facilitated by both induction of proapoptotic and suppression of antiapoptotic genes. Surprisingly, EGFR inhibition induces expression of markers of epidermal differentiation. Time course of human epidermal keratinocytes treated with Tyrphostin (AG1478) and untreated controls

ORGANISM(S): Homo sapiens

SUBMITTER: Miki Blumenberg

PROVIDER: E-GEOD-41680 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Similar Datasets

Project description:Approximately 15% of lung cancer cases are not associated with smoking and show molecular and clinical characteristics distinct from those in smokers. Epidermal growth factor receptor (EGFR) gene mutations, which are correlated with sensitivity to EGFR-tyrosine kinase inhibitors (EGFR-TKIs), are more frequent in never-smoker lung cancers. In this study, microRNA (miRNA) expression profiling of 28 never-smoker lung cancer cases identified aberrantly expressed miRNAs, which were much fewer than in lung cancers of smokers and included miRNAs previously identified (e.g., upregulated miR-21) and unidentified (e.g., downregulated miR-138) in those smoker cases. The changes in expression of some of these miRNAs were more remarkable in cases with EGFR mutations than in those without: the most upregulated miRNA, miR-21, was more abundant in cancers with EGFR mutation. A significant correlation between phosphorylated-EGFR (p-EGFR) and miR-21 levels in lung carcinoma cell lines and the suppression of miR-21 by an EGFR-TKI, AG1478, suggested that the EGFR signaling pathway positively regulated miR-21 expression. In a never-smoker-derived lung adenocarcinoma cell line H3255 with mutant EGFR and high levels of p-EGFR and miR-21, antisense inhibition of miR-21 enhanced AG1478-induced apoptosis. In a never-smoker-derived adenocarcinoma cell line H441 with wild-type EGFR, the antisense miR-21 not only showed the additive effect with AG1478 but also induced apoptosis by itself. These results suggest that aberrantly increased expression of miR-21, which is further enhanced by the activated EGFR signaling pathway, plays a critical role in lung carcinogenesis in never-smokers and is a potential therapeutic target in both EGFR mutant and wild-type cases. Twenty-eight pairs of lung cancer tissues and corresponding noncancerous lung tissues were obtained from never-smokers who had undergone surgical resection from 2000 to 2004 at the University of Maryland Medical Center (n=15), Mayo Clinic (n=7) in United States and Hamamatsu University School of Medicine (n=6) in Japan.

Dataset Information

TRANSCRIPTIONAL EFFECTS OF INHIBITING EGFR IN KERATINOCYTES

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets