FOXO1 regulates oncogenic PKC-ι expression in melanoma inversely to c-Jun in an autocrine manner via IL-17E and ICAM-1 activation

Author(s):  
WISHRAWANA RATNAYAKE ◽  
CHRISTOPHER APOSTOLATOS ◽  
SLOAN BREEDY ◽  
ANDRE APOSTOLATOS ◽  
MILDRED ACEVEDO-DUNCAN

Regardless of abundant efforts to enhance primary prevention and early detection, the number of melanoma cases in the United States has increased steadily over the past 15 years, thus greatly affecting public health and the economy. In previous studies, we demonstrated protein kinase C‑ι (PKC‑ι) to be an oncogene in melanoma, which promotes the activation of nuclear factor (NF)‑κB, thereby supporting survival and progression. In addition, we demonstrated that PKC‑ι induced the metastasis of melanoma cells by activating Vimentin, and PKC‑ι inhibition downregulated epithilial‑mesencymal transition (EMT), while inducing apoptosis. Of note, PKC‑ι specific inhibitors downregulated the expression of both PKC‑ι and phosphorylated PKC‑ι, suggesting that PKC‑ι plays a role in regulating its own expression in melanoma. In this study, we report the underlaying mechanisms of the transcriptional regulation of PKC‑ι (PRKCI gene) expression in melanoma. c‑Jun, interferon‑stimulated gene factor 3 (ISGF3), paired box gene 3 (PAX3), early growth response protein 1 (EGR1) and Forkhead box protein O1 (FOXO1), which bind on or near the promoter sequence of the PRKCI gene, were analyzed for their role in PKC‑ι regulation in SK‑MEL‑2 and MeWo cell lines. We silenced selected transcription factors using siRNA, and the results revealed that the silencing of c‑Jun and FOXO1 significantly altered the expression of PRKCI. The levels of both phosphorylated and total PKC‑ι increased upon FOXO1 silencing and decreased upon c‑Jun silencing, suggesting that c‑Jun acts as an upregulator, while FOXO1 acts as a downregulator of PRKCI expression. We also used a multiplex ELISA to analyze multiple pathways other than NF‑κB that were affected by treatment with PKC‑ι inhibitor. The silencing of NF‑κB p65 and PKC‑ι by siRNA suggested that the regulation of PKC‑ι expression was strongly associated with FOXO1. In addition, we observed a significant decrease in the mRNA levels of both interleukin (IL)‑6 and IL‑8, with a significant increase in the levels of IL‑17E and intercellular adhesion molecule 1 (ICAM‑1) upon the knockdown of expression of PKC‑ι in both cell lines. This suggested that PKC‑ι expression was affected by these cytokines in an autocrine manner. Overall, the findings of this study suggest that PKC‑ι inhibition suppresses its own expression, diminishing oncogenic signaling, while upregulating anti‑tumor signaling, thus rendering it an effective novel biomarker for use in the design of novel targeted therapeutics for melanoma.


2018 ◽  
Author(s):  
WISHRAWANA RATNAYAKE ◽  
CHRISTOPHER APOSTOLATOS ◽  
SLOAN BREEDY ◽  
ANDRE APOSTOLATOS ◽  
MILDRED ACEVEDO-DUNCAN

Regardless of abundant efforts to enhance primary prevention and early detection, the number of melanoma cases in the United States has increased steadily over the past 15 years, thus greatly affecting public health and the economy. In previous studies, we demonstrated protein kinase C‑ι (PKC‑ι) to be an oncogene in melanoma, which promotes the activation of nuclear factor (NF)‑κB, thereby supporting survival and progression. In addition, we demonstrated that PKC‑ι induced the metastasis of melanoma cells by activating Vimentin, and PKC‑ι inhibition downregulated epithilial‑mesencymal transition (EMT), while inducing apoptosis. Of note, PKC‑ι specific inhibitors downregulated the expression of both PKC‑ι and phosphorylated PKC‑ι, suggesting that PKC‑ι plays a role in regulating its own expression in melanoma. In this study, we report the underlaying mechanisms of the transcriptional regulation of PKC‑ι (PRKCI gene) expression in melanoma. c‑Jun, interferon‑stimulated gene factor 3 (ISGF3), paired box gene 3 (PAX3), early growth response protein 1 (EGR1) and Forkhead box protein O1 (FOXO1), which bind on or near the promoter sequence of the PRKCI gene, were analyzed for their role in PKC‑ι regulation in SK‑MEL‑2 and MeWo cell lines. We silenced selected transcription factors using siRNA, and the results revealed that the silencing of c‑Jun and FOXO1 significantly altered the expression of PRKCI. The levels of both phosphorylated and total PKC‑ι increased upon FOXO1 silencing and decreased upon c‑Jun silencing, suggesting that c‑Jun acts as an upregulator, while FOXO1 acts as a downregulator of PRKCI expression. We also used a multiplex ELISA to analyze multiple pathways other than NF‑κB that were affected by treatment with PKC‑ι inhibitor. The silencing of NF‑κB p65 and PKC‑ι by siRNA suggested that the regulation of PKC‑ι expression was strongly associated with FOXO1. In addition, we observed a significant decrease in the mRNA levels of both interleukin (IL)‑6 and IL‑8, with a significant increase in the levels of IL‑17E and intercellular adhesion molecule 1 (ICAM‑1) upon the knockdown of expression of PKC‑ι in both cell lines. This suggested that PKC‑ι expression was affected by these cytokines in an autocrine manner. Overall, the findings of this study suggest that PKC‑ι inhibition suppresses its own expression, diminishing oncogenic signaling, while upregulating anti‑tumor signaling, thus rendering it an effective novel biomarker for use in the design of novel targeted therapeutics for melanoma.



10.3892/wasj ◽  
2018 ◽  
Author(s):  
WISHRAWANA RATNAYAKE

Regardless of abundant efforts to enhance primary prevention and early detection, the number of melanoma cases in the United States has increased steadily over the past 15 years, thus greatly affecting public health and the economy. In previous studies, we demonstrated protein kinase C‑ι (PKC‑ι) to be an oncogene in melanoma, which promotes the activation of nuclear factor (NF)‑κB, thereby supporting survival and progression. In addition, we demonstrated that PKC‑ι induced the metastasis of melanoma cells by activating Vimentin, and PKC‑ι inhibition downregulated epithilial‑mesencymal transition (EMT), while inducing apoptosis. Of note, PKC‑ι specific inhibitors downregulated the expression of both PKC‑ι and phosphorylated PKC‑ι, suggesting that PKC‑ι plays a role in regulating its own expression in melanoma. In this study, we report the underlaying mechanisms of the transcriptional regulation of PKC‑ι (PRKCI gene) expression in melanoma. c‑Jun, interferon‑stimulated gene factor 3 (ISGF3), paired box gene 3 (PAX3), early growth response protein 1 (EGR1) and Forkhead box protein O1 (FOXO1), which bind on or near the promoter sequence of the PRKCI gene, were analyzed for their role in PKC‑ι regulation in SK‑MEL‑2 and MeWo cell lines. We silenced selected transcription factors using siRNA, and the results revealed that the silencing of c‑Jun and FOXO1 significantly altered the expression of PRKCI. The levels of both phosphorylated and total PKC‑ι increased upon FOXO1 silencing and decreased upon c‑Jun silencing, suggesting that c‑Jun acts as an upregulator, while FOXO1 acts as a downregulator of PRKCI expression. We also used a multiplex ELISA to analyze multiple pathways other than NF‑κB that were affected by treatment with PKC‑ι inhibitor. The silencing of NF‑κB p65 and PKC‑ι by siRNA suggested that the regulation of PKC‑ι expression was strongly associated with FOXO1. In addition, we observed a significant decrease in the mRNA levels of both interleukin (IL)‑6 and IL‑8, with a significant increase in the levels of IL‑17E and intercellular adhesion molecule 1 (ICAM‑1) upon the knockdown of expression of PKC‑ι in both cell lines. This suggested that PKC‑ι expression was affected by these cytokines in an autocrine manner. Overall, the findings of this study suggest that PKC‑ι inhibition suppresses its own expression, diminishing oncogenic signaling, while upregulating anti‑tumor signaling, thus rendering it an effective novel biomarker for use in the design of novel targeted therapeutics for melanoma.



Life ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1223
Author(s):  
Nour A. Ass’ad ◽  
Xin Shore ◽  
Orrin Myers ◽  
Alexandra R. Camacho ◽  
Quiteria Jacquez ◽  
...  

The United States has a rich history of mining including uranium (U)-mining, coal mining, and other metal mining. Cardiovascular diseases (CVD) are largely understudied in miners and recent literature suggests that when compared to non-U miners, U-miners are more likely to report CVD. However, the molecular basis for this phenomenon is currently unknown. In this pilot study, a New Mexico (NM)-based occupational cohort of current and former miners (n = 44) were recruited via a mobile screening clinic for miners. Serum- and endothelial-based endpoints were used to assess circulating inflammatory potential relevant to CVD. Non-U miners reported significantly fewer pack years of smoking than U-miners. Circulating biomarkers of interest revealed that U-miners had significantly greater serum amyloid A (SAA), soluble intercellular adhesion molecule 1 (ICAM-1, ng/mL), soluble vascular cell adhesion molecule 1 (VCAM-1, ng/mL), and VCAM-1 mRNA expression, as determined by the serum cumulative inflammatory potential (SCIP) assay, an endothelial-based assay. Even after adjusting for various covariates, including age, multivariable analysis determined that U-miners had significantly upregulated VCAM-1 mRNA. In conclusion, VCAM-1 may be an important biomarker and possible contributor of CVD in U-miners. Further research to explore this mechanism may be warranted.



Cancers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1861
Author(s):  
Tyler Sheetz ◽  
Joseph Mills ◽  
Anna Tessari ◽  
Megan Pawlikowski ◽  
Ashley E. Braddom ◽  
...  

Prostate cancer (PCa) is the most frequently diagnosed cancer in men and second most common cause of cancer-related deaths in the United States. Androgen deprivation therapy (ADT) is only temporarily effective for advanced-stage PCa, as the disease inevitably progresses to castration-resistant prostate cancer (CRPC). The protein nucleolin (NCL) is overexpressed in several types of human tumors where it is also mislocalized to the cell surface. We previously reported the identification of a single-chain fragment variable (scFv) immuno-agent that is able to bind NCL on the surface of breast cancer cells and inhibit proliferation both in vitro and in vivo. In the present study, we evaluated whether NCL could be a valid therapeutic target for PCa, utilizing DU145, PC3 (CRPC), and LNCaP (androgen-sensitive) cell lines. First, we interrogated the publicly available databases and noted that higher NCL mRNA levels are associated with higher Gleason Scores as well as with recurrent and metastatic tumors. Then, using our anti-NCL scFv, we demonstrated that NCL is expressed on the surface of all three tested cell lines and that NCL inhibition results in reduced proliferation and migration. We also measured the inhibitory effect of NCL targeting on the biogenesis of oncogenic microRNAs such as miR-21, -221 and -222, which was cell context dependent. Taken together, our data provide evidence that NCL targeting inhibits the key hallmarks of malignancy in PCa cells and may provide a novel therapeutic option for patients with advanced-stage PCa.



2015 ◽  
Vol 34 (3) ◽  
pp. 314-322 ◽  
Author(s):  
Bosa Mirjanić-Azarić ◽  
Zorana Jelić-Ivanović ◽  
Aleksandra Zeljković ◽  
Jelena Vekić ◽  
Günther Jürgens ◽  
...  

SummaryBackground: High-density lipoproteins (HDL) have atheroprotective biological properties: antioxidative, anti-apoptotic, anti-inflammatory, and they have the efflux capacity of cellular cholesterol. Plasma mRNA analysis can be used to investigate statin pleiotropy in vivo as a new analytical tool for non-invasive assessment of gene expression in vascular beds. The aim of this study was to assess the pleiotropic effects of atorvastatin in stable angina patients with highrisk values (group A) as compared with patients who had borderline and desirable HDL-cholesterol (HDL-C) values (group B).Methods: The atorvastatin therapy (20 mg/day) was given to forty-three patients with stable angina for 10 weeks. We investigated three statin pleiotropy-targeted genes: intercellular adhesion molecule-1, chemokine (C-C motif) ligand 2 and cathepsin S and assessed by gel electrophoresis gradient the effects of atorvastatin on HDL size and subclasses.Results: In group A, after therapy, HDL-C concentration was significantly increased but not in group B. Atorvastatin lowered plasma chemokine (C-C motif) ligand 2 and intercellular adhesion molecule-1 mRNA levels in both groups, but did not change the plasma cathepsin S mRNA levels. In group A only, baseline total bilirubin showed negative cor relations with the genes of cathepsin S (r=-0.506; p=0.023) and significantly increased after therapy.Conclusion: HDL-C and bilirubin can be promising therapeutic targets in the treatment of cardiovascular diseases. Analysis of cell-free mRNA in plasma might become a useful tool for estimating statin pleiotropy



1992 ◽  
Vol 263 (1) ◽  
pp. L79-L87 ◽  
Author(s):  
D. C. Look ◽  
S. R. Rapp ◽  
B. T. Keller ◽  
M. J. Holtzman

To evaluate the factors controlling migration of leukocytes into pulmonary airway epithelium, we determined the biochemical mechanisms responsible for the regulation of intercellular adhesion molecule-1 (ICAM-1) expression on cultured monolayers of human tracheal epithelial cells (HTECs) or SV40 virus-transformed human bronchial epithelial cells (BEAS-2B). Validation experiments with human umbilical vein endothelial cells (HUVECs) demonstrated little detectable ICAM-1 expression on unstimulated cells or on cells incubated with interferon-gamma (IFN-gamma), but HUVEC monolayers responded to interleukin-1 beta (IL-1 beta) or tumor necrosis factor-alpha (TNF-alpha) with significant increases in ICAM-1 and ICAM-1-dependent adherence of polymorphonuclear leukocytes (PMNs). HTEC monolayers also exhibited no significant basal ICAM-1 expression but, in contrast to HUVEC monolayers, had marked increases in ICAM-1 expression and ICAM-1-dependent PMN adherence only after incubation with IFN-gamma (and not after IL-1 beta or TNF-alpha) treatment. BEAS-2B cells also exhibited relatively selective IFN-gamma stimulation of ICAM-1 expression and ICAM-1-dependent PMN adherence but (like late passage HTEC) showed significant basal ICAM-1 expression. Differences in IFN-gamma effect on ICAM-1 levels between HUVEC and HTEC monolayers were not due to differences in number or responsiveness of IFN-gamma receptors, because both cell types exhibited a similar number of receptors and other IFN-gamma-dependent responses of HUVECs remained active. In all analyses, ICAM-1 mRNA levels correlated closely with detection of ICAM-1 on the cell surface.(ABSTRACT TRUNCATED AT 250 WORDS)



2001 ◽  
Vol 69 (3) ◽  
pp. 1364-1372 ◽  
Author(s):  
George T.-J. Huang ◽  
Daniel Kim ◽  
Jonathan K.-H. Lee ◽  
Howard K. Kuramitsu ◽  
Susan Kinder Haake

ABSTRACT Interaction of bacteria with mucosal surfaces can modulate the production of proinflammatory cytokines and adhesion molecules produced by epithelial cells. Previously, we showed that expression of interleukin-8 (IL-8) and intercellular adhesion molecule 1 (ICAM-1) by gingival epithelial cells increases following interaction with several putative periodontal pathogens. In contrast, expression of IL-8 and ICAM-1 is reduced after Porphyromonas gingivalis ATCC 33277 challenge. In the present study, we investigated the mechanisms that govern the regulation of these two molecules in bacterially infected gingival epithelial cells. Experimental approaches included bacterial stimulation of gingival epithelial cells by either a brief challenge (1.5 to 2 h) or a continuous coculture throughout the incubation period. The kinetics of IL-8 and ICAM-1 expression following brief challenge were such that (i) secretion of IL-8 by gingival epithelial cells reached its peak 2 h following Fusobacterium nucleatum infection whereas it rapidly decreased within 2 h after P. gingivalis infection and remained decreased up to 30 h and (ii) IL-8 and ICAM-1 mRNA levels were up-regulated rapidly 2 to 4 h postinfection and then decreased to basal levels 8 to 20 h after infection with either Actinobacillus actinomycetemcomitans, F. nucleatum, or P. gingivalis. Attenuation of IL-8 secretion was facilitated by adherent P. gingivalis strains. The IL-8 secreted from epithelial cells after F. nucleatum stimulation could be down-regulated by subsequent infection with P. gingivalisor its culture supernatant. Although these results suggested that IL-8 attenuation at the protein level might be associated with P. gingivalis proteases, the Arg- and Lys-gingipain proteases did not appear to be solely responsible for IL-8 attenuation. In addition, while P. gingivalis up-regulated IL-8 mRNA expression, this effect was overridden when the bacteria were continuously cocultured with the epithelial cells. The IL-8 mRNA levels in epithelial cells following sequential challenge with P. gingivalis andF. nucleatum and vice versa were approximately identical and were lower than those following F. nucleatum challenge alone and higher than control levels or those following P. gingivalis challenge alone. Thus, together with the protease effect, P. gingivalis possesses a powerful strategy to ensure the down-regulation of IL-8 and ICAM-1.



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