Publications by authors named "Mathew Loesch"

BACKGROUNDThe loss of insulin-like growth factor 1 (IGF-1) expression in senescent dermal fibroblasts during aging is associated with an increased risk of nonmelanoma skin cancer (NMSC). We tested how IGF-1 signaling can influence photocarcinogenesis during chronic UVB exposure to determine if fractionated laser resurfacing (FLR) of aged skin, which upregulates dermal IGF-1 levels, can prevent the occurrence of actinic keratosis (AK) and NMSC.METHODSA human skin/immunodeficient mouse xenografting model was used to test the effects of a small molecule inhibitor of the IGF-1 receptor on chronic UVB radiation.

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Importance: Surveying identical twins allows us to qualitatively separate genetic and environmental factors that may contribute to acne severity.

Objective: To study a cohort of identical and fraternal twins to identify environmental factors that may influence acne severity.

Design, Setting, Participants: A survey was administered to 139 identical and fraternal twin multiples (279 subjects) at the Annual Twins Day Festival in Twinsburg, Ohio on August 6-7, 2016.

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The activation status of the insulin-like growth factor-1 receptor (IGF-1R) regulates the cellular response of keratinocytes to ultraviolet B (UVB) exposure, both in vitro and in vivo. Geriatric skin is deficient in IGF-1 expression resulting in an aberrant IGF-1R-dependent UVB response which contributes to the development of aging-associated squamous cell carcinoma. Furthermore, our lab and others have reported that geriatric keratinocytes repair UVB-induced DNA damage less efficiently than young adult keratinocytes.

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Oxidative stress suppresses host immunity by generating oxidized lipid agonists of the platelet-activating factor receptor (PAF-R). Because many classical chemotherapeutic drugs induce reactive oxygen species (ROS), we investigated whether these drugs might subvert host immunity by activating PAF-R. Here, we show that PAF-R agonists are produced in melanoma cells by chemotherapy that is administered in vitro, in vivo, or in human subjects.

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The demand for skin resurfacing and rejuvenating procedures has progressively increased in the last decade and has sparked several advances within the skin resurfacing field that promote faster healing while minimizing downtime and side effects for patients. Several technological and procedural skin resurfacing developments are being integrated into clinical practices today allowing clinicians to treat a broader range of patients' skin types and pathologies than in years past, with noteworthy outcomes. This article will discuss some emerging and developing resurfacing therapies and treatments that are present today and soon to be available.

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Protein phosphatases are believed to coordinate with kinases to execute biological functions, but examples of such integrated activities, however, are still missing. In this report, we have identified protein tyrosine phosphatase H1 (PTPH1) as a specific phosphatase for p38gamma mitogen-activated protein kinase (MAPK) and shown their cooperative oncogenic activity through direct binding. p38gamma, a Ras effector known to act independent of its phosphorylation, was first shown to require its unique PDZ-binding motif to increase Ras transformation.

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Mitogen-activated protein kinases (MAPKs) regulate gene expression through transcription factors. However, the precise mechanisms in this critical signal event are largely unknown. Here, we show that the transcription factor c-Jun is activated by p38gamma MAPK, and the activated c-Jun then recruits p38gamma as a cofactor into the matrix metalloproteinase 9 (MMP9) promoter to induce its trans-activation and cell invasion.

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p38 mitogen-activated protein kinases (p38 MAPKs) are a group of serine/threonine protein kinases that together with ERK (extracellular signal-regulated kinases) and JNK (c-Jun N-terminal kinases) MAPKs act to convert different extracellular signals into specific cellular responses through interacting with and phosphorylating downstream targets. In contrast to the mitogenic ERK pathway, mammalian p38 MAPK family proteins (alpha, beta, gamma, and delta), with and without JNK participation, predominantly regulate inflammatory and stress response. Recent emerging evidence suggests that the p38 stress MAPK pathway may function as a tumor suppressor through regulating Ras-dependent and -independent proliferation, transformation, invasion and cell death by isoform-specific mechanisms.

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p38 MAPK family consists of four isoform proteins (alpha, beta, gamma, and delta) that are activated by the same stimuli, but the information about how these proteins act together to yield a biological response is missing. Here we show a feed-forward mechanism by which p38alpha may regulate Ras transformation and stress response through depleting its family member p38gamma protein via c-Jun-dependent ubiquitin-proteasome pathways. Analyses of MAPK kinase 6 (MKK6)-p38 fusion proteins showed that constitutively active p38alpha (MKK6-p38alpha) and p38gamma (MKK6-p38gamma) stimulates and inhibits c-Jun phosphorylation respectively, leading to a distinct AP-1 regulation.

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Vitamin D receptor (VDR) is a ligand-dependent transcription factor that mediates vitamin D(3)-induced gene expression. Our previous work has established that stress MAPK signaling stimulates VDR expression (Qi, X., Pramank, R.

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Ras is believed to stimulate invasion and growth by different effector pathways, and yet, the existence of such effectors under physiologic conditions has not been shown. Estrogen receptor (ER), on the other hand, is both anti-invasive and proliferative in human breast cancer, with mechanisms for these paradoxical actions remaining largely unknown. Our previous work showed an essential role of p38gamma mitogen-activated protein kinase in Ras transformation in rat intestinal epithelial cells, and here, we show that p38gamma integrates invasive antagonism between Ras and ER to increase human breast cancer invasion without affecting their proliferative activity.

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