skin neoplasms/phosphatase

Ectopic expression of dual-specificity phosphatase 5 (DUSP5), an inducible mitogen-activated protein (MAP) kinase phosphatase, specifically inactivates and anchors extracellular signal-regulated kinase (ERK)1/2 in the nucleus. However, the role of endogenous DUSP5 in regulating the outcome of

Non-melanoma skin cancer frequently results from chronic exposure to ultraviolet (UV) irradiation. UV-induced DNA damage activates cell cycle arrest checkpoints through degradation of the cyclin-dependent kinase activators, the cell division cycle 25 (CDC25) phosphatases. We previously reported

T-cell protein tyrosine phosphatase (TC-PTP, encoded by PTPN2) is a nonreceptor PTP that is most highly expressed in hematopoietic tissues. TC-PTP modulates a variety of physiological functions including cell cycle progression, cell survival and proliferation, and hematopoiesis through tyrosine

T-cell protein tyrosine phosphatase (TC-PTP), encoded by Ptpn2, has been shown to function as a tumor suppressor during skin carcinogenesis. In the current study, we generated a novel epidermal-specific TC-PTP-overexpressing (K5HA.Ptpn2) mouse model to show that TC-PTP contributes to the attenuation

Cutaneous squamous cell carcinoma (cSCC) is the second most common form of nonmelanoma skin cancer (NMSC), and its incidence is increasing rapidly. Metastatic cSCC accounts for the majority of deaths associated with NMSC, but the genetic basis for cSCC progression remains poorly understood. A

Ppp6c, which encodes the catalytic subunit of phosphoprotein phosphatase 6 (PP6), is conserved among eukaryotes from yeast to humans. In mammalian cells, PP6 targets IκBε for degradation, activates DNA-dependent protein kinase to trigger DNA repair, and is reportedly required for normal mitosis.

We have capitalized on the unique properties of the skin tumor promoter palytoxin, which does not activate protein kinase C, to investigate alternative mechanisms by which major signaling molecules can be modulated during carcinogenesis. We report here that palytoxin activates extracellular

Okadaic acid (OA), a toxin from the black sponge Halicondria okadai, is a specific inhibitor of serine/threonine protein phosphatases 1 (PP1) and 2A (PP2A). OA is a tumor promoter but also induces apoptosis in some tumor cell lines. In this study, we determined whether ras mutation and/or p53 status

We previously reported that deficiency in the gene encoding the catalytic subunit of protein phosphatase 6 (Ppp6c) predisposes mouse skin tissue to papilloma formation initiated by DMBA. Here, we demonstrate that Ppp6c loss acts as a tumor promoter in UVB-induced squamous cell carcinogenesis.

Okadaic acid (OA) is a prototypical non-phorbol ester skin tumor-promoting agent that works by inhibiting protein phosphatases, leading to an increase in protein phosphorylation. Increased protein phosphorylation can lead to stimulated signaling through various signal transduction pathways. One or

Chronic exposure to UV radiation can contribute to the development of skin cancer by promoting protein-tyrosine kinase (PTK) signaling. Studies show that exposure to UV radiation increases the ligand-independent activation of PTKs and induces protein-tyrosine phosphatase (PTP) inactivation. In the

Human papillomaviruses (HPV) replicate their DNA in the suprabasal layer of the infected mucosa or skin. In order to create a suitable environment for vegetative viral DNA replication HPV delay differentiation and sustain keratinocyte proliferation that can lead to hyperplasia. The mechanism