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Analysis of human in vivo irritated epidermis: differential profiles induced by sodium lauryl sulphate and nonanoic acid

ABSTRACT: Irritant contact dermatitis (ICD) pathogenesis is not completely understood and the genes participating in the epidermal response towards chemical irritants are only partly known. It is commonly accepted that different irritants have different mechanisms of action in the development of ICD. To define the differential molecular events induced in the epidermis by different irritants, we collected sequential biopsies (½, 4 and 24 hours after a single exposure and at day 11 after repeated exposure) from human volunteers exposed to sodium lauryl sulphate (SLS) or nonanoic acid (NON). Gene expression analysis using high-density oligonucleotide microarrays revealed essentially different pathway responses ½ h after exposure: NON transiently induced the IL-6 pathway as well as a number of mitogen activated signalling cascades including ERK and growth factor receptor signalling, whereas SLS transiently downregulated cellular energy metabolism pathways. Differential expression of the cyclooxygenase-2 and matrix metalloproteinase 3 transcripts was confirmed immunohistochemically. After cumulative exposure, 883 genes were differentially expressed while 26 suggested common biomarkers were identified . In conclusion, we bring new insights into two hitherto less well elucidated phases of skin irritancy: the very initial as well as the late phase after single and cumulative exposure, respectively.

ORGANISM(S): Homo sapiens

PROVIDER: GSE18206 | GEO | 2010/08/20

SECONDARY ACCESSION(S): PRJNA119569

REPOSITORIES: GEO

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Project description:Immunogenic cell death (ICD) in cancer represents a functionally unique therapeutic response that can induce tumor-targeting immune responses. ICD is characterized by the exposure and release of numerous damage-associated molecular patterns (DAMPs), which confer adjuvanticity to dying cancer cells. The spatiotemporally defined emission of DAMPs during ICD has been well described; whereas the epigenetic mechanisms that regulate ICD hallmarks have not yet been deeply elucidated. Here, we aimed to examine the involvement of miRNAs and their putative targets taking advantage from well-established in vitro models of ICD. To this end, B cell lymphoma (Mino) and breast cancer (MDA-MB-231) cell lines were exposed to two different ICD inducers: the combination of retinoic acid (RA) and interferon-alpha (IFN-a) and doxorubicin, and to non ICD inducers like gamma irradiation. Then, miRNA and mRNA profiles were studied by next generation sequencing. Co-expression analysis identified 16 miRNAs differentially modulated in cells subjected to ICD. Integrated miRNA-mRNA functional analysis revealed candidate miRNAs, mRNAs, and modulated pathways associated with Immune System Process (GO Term). In this sense, ICD induced a distinctive transcriptional signature hallmarked by regulation of antigen presentation, a crucial step for a proper immune system antitumor response activation. Interestingly, the major histocompatibility complex class I (MHC-I) pathway was upregulated whereas class II (MHC-II) was downregulated. Analysis of MHC-II associated transcripts and HLA-DR surface expression validated the inhibition of this pathway by ICD on lymphoma cells. miR-4284 and miR-212-3p were the strongest miRNAs upregulated by ICD associated with this event. It is well known that MHC-II expression on tumor cells facilitates the recruitment of CD4+ T cells. However, the interaction between tumor MHC-II and the inhibitory co-receptor LAG-3 on tumor-associated lymphocytes could provide an immunosuppressive signal that directly represses effector cytotoxic activity. In this context, MHC-II downregulation by ICD could enhance antitumor immunity. Overall, we found that the miRNA profile was significantly altered during ICD. Several miRNAs are predicted to be involved in the regulation of Class I and II MHC pathway, whose implication in ICD was demonstrated herein for the first time, which could eventually modulate tumor recognition and attack by the immune system.

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Analysis of human in vivo irritated epidermis: differential profiles induced by sodium lauryl sulphate and nonanoic acid

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