Unlike most other matrix metalloproteinases (MMPs) MMP-19 is expressed in undifferentiated basal keratinocytes of healthy human skin. The human keratinocyte cell line HaCaT, which like basal keratinocytes constitutively expresses MMP-19, down-regulated the expression of MMP-19 at high calcium concentrations. Calcium-regulation occurred through E-cadherin mediated cell-cell contacts because neut...

Thapsigargin is a specific inhibitor of the sarco/endoplasmic reticulum Ca ATPase of the endoplasmic reticulum. Here, we show that stimulation of human HaCaT keratinocytes with nanomolar concentrations of thapsigargin triggers expression of activating transcription factor (ATF) 3, a basic-region leucin zipper transcription factor. ATF3 expression was also up-regulated in thapsigargin-stimulated...

Ultraviolet A (UVA, 320-400 nm) radiation is an oxidizing agent that causes significant damage to cellular components and that leads to photoaging and cancer. It strongly induces NF-E2-related factor 2 (Nrf2) expressions in cultured FEK4 human skin fibroblasts but weakly induces it in transformed HaCaT skin keratinocytes. Nrf2 silencing increases cell damage at a moderate dose of UVA irradiatio...

Thapsigargin is a specific inhibitor of the sarco/endoplasmic reticulum Ca(2+) ATPase of the endoplasmic reticulum. Here, we show that stimulation of human HaCaT keratinocytes with nanomolar concentrations of thapsigargin triggers expression of activating transcription factor (ATF) 3, a basic-region leucin zipper transcription factor. ATF3 expression was also up-regulated in thapsigargin-stimul...

The human keratinocyte cell line HaCaT expresses essentially all epidermal differentiation markers but exhibits deficiencies in tissue organization as surface transplants in nude mice and even more so in organotypic co-cultures with fibroblasts. Whereas tissue differentiation by normal keratinocytes (NEKs) is regulated by stromal interactions, this mechanism is impaired in HaCaT cells. This reg...

DESENSITIZATION OF HACAT KERATINOCYTES TO VITAMIN D3 OCCURS VIA LOSS OF REDD1REGULATION OF THE MTOR PATHWAY

Keratinocytes proliferation is critical for the capacity to heal wounds and accumulating evidences have proved that dysregulation of microRNAs is involved in proliferation of keratinocytes. However, the molecular mechanisms remain to be completely elucidated. Here, we show that miR-136 was significantly decreased by TGF-β1 treatment in HaCaT cells and normal human epidermal keratinocytes (NHEK)...

OBJECTIVES The aim of this study was to evaluate and compare the biological effects of three resin monomers on three human gingival fibroblast (HGF) cell lines and immortalised human keratinocytes. METHODS Primary HGFs and HaCaT keratinocytes were cultured for 24h and grown to sub-confluent monolayers. Resin monomers were dissolved in dimethyl sulphoxide (DMSO) and diluted with culture medium...

Keratinocytes intrinsically migrate when wounding occurs. Scratch assays are widely used to evaluate the ability of cells on a flat surface. However, keratinocytes seem perpendicularly epidermal layer in phenomena such as elongation rete ridges and formation cysts pathological conditions. Here we present an assay for visualizing cell migration from keratinocyte sheets downward direction. HaCaT ...

Keratinocytes were shown to induce the activation of plasminogen activator resulting in the formation of plasmin and the initiation of proteolysis in vitro. Activation of surface bound plasminogen may localize protease activity in the pericellular microenvironment and play a role in inducing both a conformational change and cell locomotion. Plasmin, however, can induce non-proteolytic effects o...