Differential Tumor Biology Effects of Double-Initiation in a Mouse Skin Chemical Carcinogenesis Model Comparing Wild Type versus Protein Kinase Cepsilon Overexpression Mice

Protein kinase Calpha (PKCalpha) is one of six PKC isoforms expressed in keratinocytes of mouse epidermis. To gain an understanding of the role of epidermal PKCalpha, we have localized its expression to specific cells of normal mouse skin and examined the effect of keratin 5 (K5) promoter directed expression of PKCalpha in transgenic mice. In normal mouse skin, PKCalpha was extensively expressed in the outer root sheath (ORS) keratinocytes of the anagen hair follicle and weakly expressed in keratinocytes of interfollicular epidermis. K5-targeted expression of PKCalpha to epidermal basal keratinocytes and follicular ORS keratinocytes resulted in a tenfold increase in epidermal PKCalpha. K5-PKCalpha mice exhibited no abnormalities in keratinocyte growth and differentiation in the epidermis. However, a single topical treatment with the PKC activator, 12-O-tetradecanoylphorbol-13-acetate (TPA) resulted in a striking inflammatory response characterized by edema and extensive epidermal infiltration of neutrophils that formed intraepidermal microabscesses in the epidermis. Compared to TPA-treated wild-type mice, the epidermis of TPA-treated K5-PKCalpha mice displayed increased expression of cyclooxygenase-2 (COX-2), the neutrophil chemotactic factor macrophage inflammatory protein-2 (MIP-2) mRNA and the proinflammatory cytokine TNFalpha mRNA but not IL-6 or IL-1alpha mRNA. To determine if K5-PKCalpha mice display an altered response to TPA-promotion, 7, 12-dimethylbenz[a]anthracene-initiated K5-PKCalpha mice and wild-type mice were promoted with TPA. No differences in papilloma incidence or multiplicity were observed between K5-PKCalpha mice and wild-type littermates. These results demonstrate that the overexpression of PKCalpha in epidermis increases the expression of specific proinflammatory mediators and induces cutaneous inflammation but has little to no effect on epidermal differentiation, proliferation or TPA tumor promotion.

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Faculty Opinions recommendation of Gene induction following wounding of wild-type versus macrophage-deficient Drosophila embryos.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1103556.559624 ◽

2008 ◽

Author(s):

Andrew Chisholm

Keyword(s):

Gene Induction ◽

Type Versus ◽

Wild Type ◽

Drosophila Embryos

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Knockout of Putative Tumor Suppressor Aldh1l1 in Mice Reprograms Metabolism to Accelerate Growth of Tumors in a Diethylnitrosamine (DEN) Model of Liver Carcinogenesis

Cancers ◽

10.3390/cancers13133219 ◽

2021 ◽

Vol 13 (13) ◽

pp. 3219

Author(s):

Natalia I. Krupenko ◽

Jaspreet Sharma ◽

Halle M. Fogle ◽

Peter Pediaditakis ◽

Kyle C. Strickland ◽

...

Keyword(s):

Tumor Growth ◽

Chemical Carcinogenesis ◽

Dependent Manner ◽

Wild Type ◽

Liver Carcinogenesis ◽

Wild Type Littermate ◽

Tumor Multiplicity ◽

Accelerate Growth ◽

Putative Tumor Suppressor ◽

Formyltetrahydrofolate Dehydrogenase

Cytosolic 10-formyltetrahydrofolate dehydrogenase (ALDH1L1) is commonly downregulated in human cancers through promoter methylation. We proposed that ALDH1L1 loss promotes malignant tumor growth. Here, we investigated the effect of the Aldh1l1 mouse knockout (Aldh1l1−/−) on hepatocellular carcinoma using a chemical carcinogenesis model. Fifteen-day-old male Aldh1l1 knockout mice and their wild-type littermate controls (Aldh1l1+/+) were injected intraperitoneally with 20 μg/g body weight of DEN (diethylnitrosamine). Mice were sacrificed 10, 20, 28, and 36 weeks post-DEN injection, and livers were examined for tumor multiplicity and size. We observed that while tumor multiplicity did not differ between Aldh1l1−/− and Aldh1l1+/+ animals, larger tumors grew in Aldh1l1−/− compared to Aldh1l1+/+ mice at 28 and 36 weeks. Profound differences between Aldh1l1−/− and Aldh1l1+/+ mice in the expression of inflammation-related genes were seen at 10 and 20 weeks. Of note, large tumors from wild-type mice showed a strong decrease of ALDH1L1 protein at 36 weeks. Metabolomic analysis of liver tissues at 20 weeks showed stronger differences in Aldh1l1+/+ versus Aldh1l1−/− metabotypes than at 10 weeks, which underscores metabolic pathways that respond to DEN in an ALDH1L1-dependent manner. Our study indicates that Aldh1l1 knockout promoted liver tumor growth without affecting tumor initiation or multiplicity.

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Effects of phorbol ester on mitogen-activated protein kinase kinase activity in wild-type and phorbol ester-resistant EL4 thymoma cells

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)85398-x ◽

1993 ◽

Vol 268 (22) ◽

pp. 16124-16129

Author(s):

K.C. Gause ◽

M.K. Homma ◽

K.A. Licciardi ◽

R. Seger ◽

N.G. Ahn ◽

...

Keyword(s):

Protein Kinase ◽

Phorbol Ester ◽

Kinase Activity ◽

Mitogen Activated Protein Kinase ◽

Wild Type ◽

Mitogen Activated Protein ◽

Protein Kinase Kinase

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The protein kinase C activator, phorbol ester, cooperates with the wild-type p53 species of Ras-transformed embryo fibroblasts growth arrest.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)43919-1 ◽

1994 ◽

Vol 269 (47) ◽

pp. 29579-29587

Author(s):

C Delphin ◽

J Baudier

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Phorbol Ester ◽

Growth Arrest ◽

Wild Type ◽

Kinase C ◽

Wild Type P53 ◽

Embryo Fibroblasts

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TRAF6-Dependent Mitogen-Activated Protein Kinase Activation Differentially Regulates the Production of Interleukin-12 by Macrophages in Response to Toxoplasma gondii

Infection and Immunity ◽

10.1128/iai.72.10.5662-5667.2004 ◽

2004 ◽

Vol 72 (10) ◽

pp. 5662-5667 ◽

Cited By ~ 43

Author(s):

Nicola J. Mason ◽

Jim Fiore ◽

Takashi Kobayashi ◽

Katherine S. Masek ◽

Yongwon Choi ◽

...

Keyword(s):

Protein Kinase ◽

Toxoplasma Gondii ◽

Signaling Pathways ◽

Intracellular Signaling ◽

Mitogen Activated Protein Kinase ◽

Interleukin 12 ◽

Wild Type ◽

Kinase Activation ◽

Extracellular Signal ◽

Mitogen Activated Protein

ABSTRACT The production of interleukin-12 (IL-12) is critical to the development of innate and adaptive immune responses required for the control of intracellular pathogens. Many microbial products signal through Toll-like receptors (TLR) and activate NF-κB family members that are required for the production of IL-12. Recent studies suggest that components of the TLR pathway are required for the production of IL-12 in response to the parasite Toxoplasma gondii; however, the production of IL-12 in response to this parasite is independent of NF-κB activation. The adaptor molecule TRAF6 is involved in TLR signaling pathways and associates with serine/threonine kinases involved in the activation of both NF-κB and mitogen-activated protein kinase (MAPK). To elucidate the intracellular signaling pathways involved in the production of IL-12 in response to soluble toxoplasma antigen (STAg), wild-type and TRAF6−/− mice were inoculated with STAg, and the production of IL-12(p40) was determined. TRAF6−/− mice failed to produce IL-12(p40) in response to STAg, and TRAF6−/− macrophages stimulated with STAg also failed to produce IL-12(p40). Studies using Western blot analysis of wild-type and TRAF6−/− macrophages revealed that stimulation with STAg resulted in the rapid TRAF6-dependent phosphorylation of p38 and extracellular signal-related kinase, which differentially regulated the production of IL-12(p40). The studies presented here demonstrate for the first time that the production of IL-12(p40) in response to toxoplasma is dependent upon TRAF6 and p38 MAPK.

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Dose-related inhibition of chemical carcinogenesis in mouse skin by caffeine

Nature ◽

10.1038/252069a0 ◽

1974 ◽

Vol 252 (5478) ◽

pp. 69-70 ◽

Cited By ~ 64

Author(s):

K. ROTHWELL

Keyword(s):

Mouse Skin ◽

Chemical Carcinogenesis

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A Regulator of G Protein Signaling-containing Kinase Is Important for Chemotaxis and Multicellular Development inDictyostelium

Molecular Biology of the Cell ◽

10.1091/mbc.e02-08-0550 ◽

2003 ◽

Vol 14 (4) ◽

pp. 1727-1743 ◽

Cited By ~ 17

Author(s):

Binggang Sun ◽

Richard A. Firtel

Keyword(s):

Protein Kinase ◽

G Protein ◽

Kinase Activity ◽

Site Directed Mutagenesis ◽

Membrane Localization ◽

Pleckstrin Homology Domain ◽

G Protein Signaling ◽

Protein Signaling ◽

Wild Type ◽

Gene Encoding

We have identified a gene encoding RGS domain-containing protein kinase (RCK1), a novel regulator of G protein signaling domain-containing protein kinase. RCK1 mutant strains exhibit strong aggregation and chemotaxis defects. rck1 null cells chemotax ∼50% faster than wild-type cells, suggesting RCK1 plays a negative regulatory role in chemotaxis. Consistent with this finding, overexpression of wild-type RCK1 reduces chemotaxis speed by ∼40%. On cAMP stimulation, RCK1 transiently translocates to the membrane/cortex region with membrane localization peaking at ∼10 s, similar to the kinetics of membrane localization of the pleckstrin homology domain-containing proteins CRAC, Akt/PKB, and PhdA. RCK1 kinase activity also increases dramatically. The RCK1 kinase activity does not rapidly adapt, but decreases after the cAMP stimulus is removed. This is particularly novel considering that most other chemoattractant-activated kinases (e.g., Akt/PKB, ERK1, ERK2, and PAKa) rapidly adapt after activation. Using site-directed mutagenesis, we further show that both the RGS and kinase domains are required for RCK1 function and that RCK1 kinase activity is required for the delocalization of RCK1 from the plasma membrane. Genetic evidence suggests RCK1 function lies downstream from Gα2, the heterotrimeric G protein that couples to the cAMP chemoattractant receptors. We suggest that RCK1 might be part of an adaptation pathway that regulates aspects of chemotaxis in Dictyostelium.

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Activated Protein C Strengthens Cardiac Tolerance to Ischemic Insults in Aging

Circulation Research ◽

10.1161/circresaha.121.319044 ◽

2021 ◽

Author(s):

Di Ren ◽

Julia Fedorova ◽

Kayla Davitt ◽

Tran Ngoc Van Le ◽

John H Griffin ◽

...

Keyword(s):

Protein Kinase ◽

Protein C ◽

Ex Vivo ◽

Activated Protein C ◽

Wild Type ◽

Endothelial Protein C Receptor ◽

Cardiac Damage ◽

Downstream Signaling ◽

Cardioprotective Effects ◽

Epcr Shedding

Background: Activated protein C (APC) is a plasma serine protease with anticoagulant and anti-inflammatory activities. Endothelial protein C receptor (EPCR) is associated with APC's activity and mediates its downstream signaling events. APC exerts cardioprotective effects during ischemia and reperfusion (I/R). This study aims to characterize the role of the APC-EPCR axis in ischemic insults in aging. Methods: Young (3-4 months) and aged (24-26 months) wild type C57BL/6J mice, as well as EPCR point mutation (EPCR R84A/R84A ) knock-in C57BL/6J mice incapable of interaction with APC and its wild type of littermate C57BL/6J mice, were subjected to I/R. Wild type APC, signaling-selective APC-2Cys, or anticoagulant-selective APC-E170A were administrated before reperfusion. Results: The results demonstrated that cardiac I/R reduces APC activity, and the APC activity was impaired in the aged versus young hearts possibly attributable to the declined EPCR level with aging. Serum EPCR measurement showed that I/R triggered the shedding of membrane EPCR into circulation, while administration of APC attenuated the I/R-induced EPCR shedding in both young and aged hearts. Subsequent echocardiography showed that APC and APC-2Cys but not APC-E170A ameliorated cardiac dysfunction during I/R in both young and aged mice. Importantly, APC elevated the resistance of the aged heart to ischemic insults through stabilizing EPCR. However, all these cardioprotective effects of APC were blunted in the EPCR R84A/R84A mice versus its wild-type littermates. The ex vivo working heart and metabolomics results demonstrated that AMP-activated protein kinase (AMPK) mediates acute adaptive response while protein kinase B (AKT) is involved in chronic metabolic programming in the hearts with APC treatment. Conclusions: I/R stress causes shedding of the membrane EPCR in the heart, and administration of APC prevents I/R-induced cardiac EPCR shedding that is critical for limiting cardiac damage in aging.

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Regulation of rat Na+-K+-ATPase activity by PKC is modulated by state of phosphorylation of Ser-943 by PKA

AJP Cell Physiology ◽

10.1152/ajpcell.1997.273.6.c1981 ◽

1997 ◽

Vol 273 (6) ◽

pp. C1981-C1986 ◽

Cited By ~ 32

Author(s):

Xian-Jun Cheng ◽

Jan-Olov Höög ◽

Angus C. Nairn ◽

Paul Greengard ◽

Anita Aperia

Keyword(s):

Enzyme Activity ◽

Protein Kinase C ◽

Protein Kinase ◽

Response To Treatment ◽

Wild Type ◽

Wild Type Enzyme ◽

Present Evidence ◽

Cos Cells ◽

Kinase C ◽

Kinase A

We have previously shown that the rat Na+-K+-ATPase α1-isoform is phosphorylated at Ser-943 by protein kinase A (PKA) and at Ser-23 by protein kinase C (PKC), which in both cases results in inhibition of enzyme activity. We now present evidence that suggests that the phosphorylation of Ser-943 by PKA modulates the response of Na+-K+-ATPase to PKC. Rat Na+-K+-ATPase α1 or a mutant in which Ser-943 was changed to Ala-943 was stably expressed in COS cells. The inhibition of enzyme activity measured in response to treatment with the phorbol ester, phorbol 12,13-dibutyrate (PDBu; 10−6 M), was significantly reduced in the cells expressing the Ala-943 mutant compared with that observed in cells expressing wild-type enzyme. In contrast, for cells expressing Na+-K+-ATPase α1 in which Ser-943 was mutated to Asp-943, the effect of PDBu was slightly enhanced. The PDBu-induced inhibition was not mediated by activation of the adenosine 3′,5′-cyclic monophosphate/PKA system and was not achieved via direct phosphorylation of Ser-943. Sp-5,6-DCl-cBIMPS, a specific PKA activator, increased the phosphorylation of Ser-943, and this was associated with an enhanced response to PDBu. Thus the effect of PKC on rat Na+-K+-ATPase α1 is determined not only by the activity of PKC but also by the state of phosphorylation of Ser-943.

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