casein-kinase-ii and Adenocarcinoma

Protein kinase CK2 (previously known as casein kinase II) is a protein serine/threonine kinase that has been implicated in cell growth and proliferation. The focus of this review is on the apparent role of CK2 in cancer. Studies from several laboratories have shown a dysregulated expression of the kinase in tumors. Nuclear matrix and chromatin appear to be key sites for signaling of the CK2 activity in relation to cell growth. Several types of growth stimuli produce a common downstream response in CK2 by enhancing its nuclear shuttling. The neoplastic change is also associated with changes in intracellular localization of the kinase so that a higher nuclear localization is observed in tumor cells compared with normal cells. Experimental studies suggest that dysregulated expression of the alpha subunit of CK2 imparts an oncogenic potential in the cells such that in cooperation with certain oncogenes it produces a profound enhancement of the tumor phenotype. Recent studies have provided evidence that overexpression of CK2 in tumor cells is not simply a reflection of tumor cell proliferation alone but additionally may reflect the pathobiological characteristics of the tumor. Of considerable interest is the possibility that CK2 dysregulation in tumors may influence the apoptotic activity in those cells. Approaches to interfering with the CK2 signal may provide a useful means for inducing tumor cell death.

Topics: Adenocarcinoma; Animals; Apoptosis; Carcinoma, Squamous Cell; Casein Kinase II; Cell Nucleus; Chromatin; Head and Neck Neoplasms; Humans; Immunohistochemistry; Male; Neoplasms; Nuclear Matrix; Prostatic Neoplasms; Protein Serine-Threonine Kinases; Signal Transduction

Although long noncoding RNAs (lncRNAs) in lung adenocarcinoma (LUAD) have been increasingly studied, LINC01426 has not been fully investigated in LUAD. The GEPIA database revealed that LINC01426 was upregulated in LUAD tissues. In our study, we further verified the significantly high expression of LINC01426 in LUAD tissues and cell lines. We also analyzed the LINC01426 expression level and LUAD clinical features and found that high LINC01426 expression was associated with tumor diameter; tumor, node, and metastases (TNM) staging; lymph node metastasis (LNM); and overall survival (OS) rate of LUAD patients. In vitro experiments revealed that suppression of LINC01426 could repress the proliferation, migration and invasion of LUAD cells. Then, the bioinformatic analysis revealed that there were binding domains between miR-125a-5p and the 3'-UTR of LINC01426. As revealed by dual-luciferase reporter gene experiment and RNA Binding Protein Immunoprecipitation (RIP) assay, miR-125a-5p could bind to LINC01426. Additionally, the results of qRT-PCR and Pearson's analysis respectively revealed that miR-125a-5p was slightly expressed in LUAD and its expression was negatively correlated with LINC01426. Moreover, casein kinase 2 alpha 1 (CSNK2A1) was predicted to bind to miR-125a-5p. CSNK2A1 expression was remarkably high in LUAD tissues, negatively associated with miR-125a-5p, and positively correlated with LINC01426. Subsequently, our results showed that CSNK2A1 enhanced the malignant progression of LUAD cells. Overall, our study revealed that LINC01426 might regulate the malignant phenotype of LUAD via the miR-125a-5p/CSNK2A1 axis.

Topics: Adenocarcinoma; Apoptosis; Casein Kinase II; Cell Line, Tumor; Cell Movement; Cell Proliferation; Gene Expression Regulation, Neoplastic; Humans; Lung; MicroRNAs; RNA, Long Noncoding

Lung cancer is the leading cancer-related death worldwide. Patients with lung cancer mainly died of tumor metastasis and invasion. Protein kinase CK2 is an ubiquitous serine/threonine protein kinase and is frequently upregulated in various human tumors. This study aims to explore the effect and molecular mechanism of the invasion and migration of lung adenocarcinoma A549 cells after knock-down of CK2α expression.. The pSilencerTM 4.1-siCK2α-eGFP of lentiviral-mediated shRNA was constructed. The expression of CK2α was knock-downed, and a stable A549 cell line was established. The invasion and migration of A549 cell line was detected through Transwell and Boyden chamber assays. The protein expression of the PI3K/Akt signaling pathway and mesenchymal-to-epithelial transition (EMT) was evaluated using Western blot analysis.. The invasion and migration of A549 cells were significantly inhibited after the knockdown of CK2α expression compared with that in the control group. p-PTEN, Akt, p-Akt473, p-Akt308, p-PDK1, p-c-Raf, and p-GSK-3β were significantly downregulated, whereas PTEN was upregulated. Moreover, vimentin, β-catenin, Snail, MMP2, and MMP9 were significantly downregulated after reducing the CK2α expression.. CK2α might regulate the invasion and migration of A549 cells through the PI3K/Akt/GSK-3β/Snail signaling pathway, which controls EMT in lung adenocarcinoma.
.. 背景与目的 肺癌已成为全球癌症死亡的首要原因，而侵袭和转移是导致肿瘤死亡的主要原因之一，蛋白激酶CK2是一种高度保守信使非依赖性丝氨酸苏氨酸蛋白激酶，其在各种肿瘤中高表达。本研究旨在探讨下调CK2α基因表达对肺腺癌A549细胞侵袭迁移的影响以及可能的机制。方法 构建pSilencerTM 4.1-shCK2α-eGFP慢病毒表达载体，建立稳定干扰CK2α表达的A549细胞株。利用Transwell和Boyden小室实验检测干扰CK2α表达前后A549细胞的侵袭及迁移的能力。Western blot检测PI3K/Akt信号通路和上皮-间充质转化（mesenchymal-to-epithelial transition, EMT）相关蛋白的表达。结果 与对照组相比，干扰CK2α表达后肺腺癌A549细胞的侵袭及迁移能力明显下降，p-PTEN、Akt、p-Akt473、p-Akt308、 p-PDK1、p-c-Raf、p-GSK-3β蛋白明显下调，PTEN蛋白表达水平显著上调。上皮-间充质转化的相关蛋白E-cadherin蛋白表达水平显著上调，而Vimentin、β-catenin、Snail蛋白表达水平显著下调，与侵袭转移相关蛋白的MMP2、MMP9表达水平显著下调。结论 CK2α可能通过PI3K/Akt/GSK-3β/Snail信号通路来调控上皮-间充质转化参与肺腺癌A549细胞的侵袭及迁移。.

Topics: A549 Cells; Adenocarcinoma; Adenocarcinoma of Lung; Casein Kinase II; Cell Movement; Glycogen Synthase Kinase 3 beta; Humans; Lung Neoplasms; Neoplasm Metastasis; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Signal Transduction

N-α-acetyltransferase D (NatD) mediates N-α-terminal acetylation (Nt-acetylation) of histone H4 known to be involved in cell growth. Here we report that NatD promotes the migratory and invasive capabilities of lung cancer cells in vitro and in vivo. Depletion of NatD suppresses the epithelial-to-mesenchymal transition (EMT) of lung cancer cells by directly repressing the expression of transcription factor Slug, a key regulator of EMT. We found that Nt-acetylation of histone H4 antagonizes histone H4 serine 1 phosphorylation (H4S1ph), and that downregulation of Nt-acetylation of histone H4 facilitates CK2α binding to histone H4 in lung cancer cells, resulting in increased H4S1ph and epigenetic reprogramming to suppress Slug transcription to inhibit EMT. Importantly, NatD is commonly upregulated in primary human lung cancer tissues where its expression level correlates with Slug expression, enhanced invasiveness, and poor clinical outcomes. These findings indicate that NatD is a crucial epigenetic modulator of cell invasion during lung cancer progression.NatD is an acetyltransferase responsible for N-α-terminal acetylation of the histone H4 and H2A and has been linked to cell growth. Here the authors show that NatD-mediated acetylation of histone H4 serine 1 competes with the phosphorylation by CK2α at the same residue thus leading to the upregulation of Slug and tumor progression.

Topics: A549 Cells; Adenocarcinoma; Animals; Carcinoma, Squamous Cell; Casein Kinase II; Cell Movement; China; Epithelial-Mesenchymal Transition; Female; HEK293 Cells; Histones; Humans; Lung Neoplasms; Male; Mice; Middle Aged; N-Terminal Acetyltransferase D; Neoplasm Invasiveness; Phosphorylation; Snail Family Transcription Factors

To explore whether quninalizarin, an specific inhibitor of protein kinase CK2, could sensitize icotinib in EGFR-TKIs (epithelial growth factor receptor-tyrosine kinase inhibitor)-resistant cell lines and uncover the underlying mechanisms.. MTT assay was performed to evaluate the inhibitory effect of quninalizarin, icotinib or the combination of both on cell proliferation in several lung adenocarcinoma cell lines. Western blot assay was used to assess if combined inhibition of EGFR and protein kinase CK2 by icotinib and quninalizarin, exerts effect on the expression and phosphorylation of major proteins of EGFR signaling pathways.. The IC50 of HCC827, H1650, H1975 and A549 cells for icotinib were (8.07±2.00)μmol/L, (66.01±6.64)μmol/L, (265.60±9.47)μmol/L and (87.88±6.8)μmol/L, respectively, indicating that HCC827 cells are sensitive to icotinib, and the H1650, H1975 and A549 cells are relatively resistant to icotinib. When treated with both quninalizarin and icotinib in the concentration of 50 μmol/L, the viability of H1650, H1975 and A549 cells was (40.64±3.73)%, (65.74±3.27)% and (44.96±0.48)%, respectively, significantly lower than that of H1650, H1975 and A549 cells treated with 50 μmol/L icotinib alone (55.05±1.22)%, (71.98±1.60)% and (61.74±6.18)%, respectively (P<0.01 for all). When treated with both 100 μmol/L quninalizarin and 100 μmol/L icotinib, the viability of H1650, H1975 and A549 ells were (23.35±0.81)%, (55.70±1.03)%, (33.42±1.33)%, respectively, significantly lower than the viability of H1650, H1975 and A549 cells treated with 100 μmol/L icotinib alone (40.57±2.65)%, (62.40±2.05)% and (44.97±8.20)%, respectively, (P<0.01 for all). The two-way ANOVA analysis showed that compared with the viability of EGFR-TKIs-resistant cells (H1650, H1975, A549) treated with 50 μmol/L and 100 μmol/L icotinib alone, the viability of cells treated with icotinib and quinalizarin were significantly suppressed, and the differences were statistically significant (P<0.01). In addition, the phosphorylation form of Akt and ERK (namely p-Akt and p-ERK) were significantly down-regulated by treating with quninalizarin and icotinib together in the H1650 cells while the expression of Akt and ERK changed little.. Quinalizarin, as a specific CK2 inhibitor, may overcome icotinib resistance by inhibiting proliferation mediated by Akt and ERK in human lung adenocarcinoma cell lines, and enhances the suppressive effect of icotinib on the proliferation of EGFR-TKIs-resistant human lung adenocarcinoma cells.

Topics: Adenocarcinoma; Adenocarcinoma of Lung; Analysis of Variance; Anthraquinones; Apoptosis; Casein Kinase II; Cell Line, Tumor; Cell Proliferation; Cell Survival; Crown Ethers; Down-Regulation; Drug Combinations; Drug Resistance, Neoplasm; Drug Synergism; ErbB Receptors; Humans; Lung Neoplasms; Phosphorylation; Protein-Tyrosine Kinases; Quinazolines; Signal Transduction

CK2α has diverse effects on the tumorigenesis owing to its kinase activity, which phosphorylates various proteins involved in tumorigenesis. We, therefore, investigated the expression and role of CK2α in the phosphorylation of deleted in breast cancer 1 (DBC1) in gastric carcinomas. We used 187 gastric carcinomas and human gastric cancer cells to investigate the roles and relationship between CK2α and DBC1 in gastric carcinomas. Positive expression of CK2α and phospho-DBC1 predicted shorter overall survival and relapse-free survival by univariate analysis. Especially, CK2α expression was an independent prognostic indicator for gastric carcinoma patients. In gastric carcinoma cells, CK2α was bound to DBC1 and phosphorylated DBC1. The phosphorylation of DBC1 by CK2α was evidenced by co-immunoprecipitation of CK2α and DBC1 in a GST pull-down assay, an in vitro kinase assay, and immunofluorescence staining. Inhibition of both CK2α and DBC1 decreased proliferation and invasive activity of cancer cells. Decreased migration and invasive activity was associated with a downregulation of MMP2, MMP9 and the epithelial-mesenchymal transition. A mutation at the phosphorylation site of DBC1 also downregulated the signals related with the epithelial-mesenchymal transition. Our study demonstrated that CK2α is an independent prognostic indicator for gastric carcinoma patients and is involved in tumorigenesis by regulating the phosphorylation of DBC1. In addition, the blocking of CK2α and DBC1 inhibited the proliferation and invasive potential of gastric cancer cells. Therefore, our study suggests that CK2α-DBC1 pathway might be a new therapeutic target for the treatment of gastric carcinoma.

Topics: Adaptor Proteins, Signal Transducing; Adenocarcinoma; Casein Kinase II; Cell Movement; Cell Proliferation; Disease Progression; Female; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Phosphorylation; Prognosis; Protein Processing, Post-Translational; Stomach Neoplasms

Maintenance of T cell immune homeostasis is critical for adequate anti-tumor immunity. The transcription factor Ikaros is essential for lymphocyte development including T cells. Alterations in Ikaros expression occur in blood malignancies in humans and mice. In this study, we investigated the role of Ikaros in regulating T cell immune balance in pancreatic cancer mouse models.. Using our Panc02 tumor-bearing (TB) mouse model, western blot analysis revealed a reduction in Ikaros proteins while qRT-PCR showed no differences in Ikaros mRNA levels in TB splenocytes compared to control. Treatment of naïve splenocytes with the proteasomal inhibitor, MG132, stabilized Ikaros expression and prevented Ikaros downregulation by Panc02 cells, in vitro. Western blot analyses showed a reduction in protein phosphatase 1 (PP1) and protein kinase CK2 expression in TB splenocytes while CK2 activity was increased. Immunofluorescence microscopy revealed altered punctate staining of Ikaros in TB splenocytes. Flow cytometry revealed a significant decrease in effector CD4+ and CD8+ T cell percentages but increased CD4+CD25+ regulatory T cells in TB splenocytes. Similar alterations in T cell percentages, as well as reduced Ikaros and CK2 but not PP1 expression, were observed in a transgenic, triple mutant (TrM) pancreatic cancer model. Ikaros expression was also reduced in enriched TB CD3+ T cells. MG132 treatment of naïve CD3+ T cells stabilized Ikaros expression in the presence of Panc02 cells. Western blots showed reduced PP1 and CK2 expression in TB CD3+ T cells.. The results of this study suggest that the pancreatic tumor microenvironment may cause proteasomal degradation of Ikaros, possibly via dysregulation of PP1 and CK2 expression and activity, respectively. This loss of Ikaros expression may contribute to an imbalance in T cell percentages. Ikaros may potentially be a therapeutic target to restore T cell homeostasis in pancreatic cancer hosts, which may be critical for effective anti-tumor immunity.

Topics: Adenocarcinoma; Animals; Casein Kinase II; CD3 Complex; Cell Line, Tumor; Disease Models, Animal; Female; Gene Expression Regulation, Neoplastic; Homeostasis; Ikaros Transcription Factor; Lymphocyte Count; Mice; Pancreatic Neoplasms; Proteasome Endopeptidase Complex; Proteolysis; Receptors, Neuropeptide Y; T-Lymphocytes; Ubiquitin

Protein kinase CK2 is widely expressed in eukaryotic cells, and plays an important role in cell proliferation, migration, apoptosis, etc. The aim of the current study is to explore how Quinalizarin, a specific CK2 inhibitor, affects the cell proliferation, migration, and apoptosis of different pathological and genetic types of human lung cancer cell lines.. MTT assays were performed to evaluate the cell viability after being treated by Quinalizarin. Transwell migration assays were used to assess whether Quinalizarin could suppress cell migration. Flow cytometry was employed to test the apoptosis rate of different cells.. After being treated by Quinalizarin, the viability of different pathological types of lung cancer cells (H446, H460, A549) were significantly suppressed in a time and dose-dependent manner. More interestingly, in a serial of human lung adenocarcinoma cell lines with different epidermal growth factor receptor (EGFR) mutation status, Quinalizarin was shown to have a much better ability to reduce the viability of cells with EGFR sensitive mutation than those with resistance mutations. Meanwhile, we also found that the cell migration of different pathological types of lung cancer cells (H446, H460, A549) was significantly decreased by Quinalizarin dose-dependently. In addition, the apoptosis rates in those cells were proved to be increased after exposed to Quinalizarin.. Quinalizarin, the specific CK2 inhibitor, could reduce cell viability with emphasis on adenocarcinoma cells harboring EGFR sensitive mutation, suppresses migration, and accelerates apoptosis in different human lung cancer cell lines.

Topics: Adenocarcinoma; Apoptosis; Carcinoma, Large Cell; Casein Kinase II; Cell Movement; Cell Proliferation; Flow Cytometry; Humans; Lung Neoplasms; Quinazolines; Small Cell Lung Carcinoma; Tumor Cells, Cultured

The epithelial-to-mesenchymal transition (EMT) is a major phenotype of cancer metastasis and invasion. As a druggable cancer target, the inhibition of protein kinase CK2 (formally named to casein kinase 2) has been suggested as a promising therapeutic strategy to treat EMT-controlled cancer metastasis. This study aimed to evaluate the effect of the CK2 inhibitor CX-4945 on the processes of cancer migration and invasion during the EMT in A549 human lung adenocarcinoma cells.. The effect of CX-4945 on TGF-β1-induced EMT was evaluated in A549 cells treated with TGF-β1 (5 ng/ml) and CX-4945. The effect of CX-4945 on TGF-β1-induced cadherin switch and activation of key signaling molecules involved in Smad, non-Smad, Wnt and focal adhesion signaling pathways were investigated by Western blot analysis, immunocytochemistry and reporter assay. Additionally, the effect of CX-4945 on TGF-β1-induced migration and invasion was investigated by wound healing assay, Boyden chamber assay, gelatin zymography, and the quantitative real-time PCR.. CX-4945 inhibits the TGF-β1-induced cadherin switch and the activation of key signaling molecules involved in Smad (Smad2/3, Twist and Snail), non-Smad (Akt and Erk), Wnt (β-catenin) and focal adhesion signaling pathways (FAK, Src and paxillin) that cooperatively regulate the overall process of EMT. As a result, CX-4945 inhibits the migration and invasion of A549 cells accompanied with the downregulation of MMP-2 and 9.. Clinical evaluation of CX-4945 in humans as a single agent in solid tumors and multiple myeloma has established its promising pharmacokinetic, pharmacodynamic, and safety profiles. Beyond regression of tumor mass, CX-4945 may be advanced as a new therapy for cancer metastasis and EMT-related disorders.

Topics: Adenocarcinoma; Adenocarcinoma of Lung; Cadherins; Casein Kinase II; Cell Line, Tumor; Cell Movement; Epithelial-Mesenchymal Transition; Focal Adhesion Kinase 1; Humans; Lung Neoplasms; Naphthyridines; Neoplasm Invasiveness; Paxillin; Phenazines; Protein Kinase Inhibitors; Signal Transduction; Smad Proteins; Transforming Growth Factor beta1; Wnt Proteins

Cell surface nucleolin (NCL) plays fundamental roles in tumor angiogenesis. However, the mechanism underlying its surface translocation remains obscure. The present study discovered that heat shock cognate 70 (Hsc70) is essential in both the surface translocation and the angiogenic function of NCL.. We identified that Hsc70 interacted with NCL in endothelial cells via the peptide-binding domain of Hsc70 and the RNA-binding domain of NCL. Functional knockdown of Hsc70 remarkably inhibited the expression of surface NCL, which was rescued by wild-type Hsc70 rather than its truncations. Phosphorylation of NCL by either protein kinase C-ξ or casein kinase 2 mediated its interaction with Hsc70 and the surface expression. Hsc70 regulated NCL translocation via stabilizing NCL and enhancing its interaction with nonmuscle myosin heavy chain 9. Moreover, Hsc70 was associated with NCL-induced endothelial cell migration and tubule formation in vitro and angiogenesis in both matrigel plugs and xenograft tumors. Tissue array analysis revealed that the expression levels of NCL and Hsc70 were intimately correlated in human lung adenocarcinomas.. Our study demonstrates that Hsc70 is a prerequisite for the surface translocation and angiogenic function of NCL, which suggests strategies to target both Hsc70 and NCL for more effective antiangiogenic therapies.

Topics: Adenocarcinoma; Adenocarcinoma of Lung; Animals; Benzhydryl Compounds; Binding Sites; Carcinoma, Non-Small-Cell Lung; Casein Kinase II; Cell Line, Tumor; Cell Movement; HSC70 Heat-Shock Proteins; Human Umbilical Vein Endothelial Cells; Humans; Lung Neoplasms; Mice; Mice, Nude; Myosin Heavy Chains; Neovascularization, Pathologic; Neovascularization, Physiologic; Nucleolin; Phosphoproteins; Phosphorylation; Protein Interaction Domains and Motifs; Protein Interaction Mapping; Protein Kinase C-epsilon; Protein Stability; Protein Transport; Pyrrolidinones; RNA Interference; RNA-Binding Proteins; Tissue Array Analysis; Transfection; Xenograft Model Antitumor Assays

Elevated level of oxygen (hyperoxia) is widely used in critical care units and in respiratory insufficiencies. In addition, hyperoxia has been implicated in many diseases such as bronchopulmonary dysplasia or acute respiratory distress syndrome. Although hyperoxia is known to cause DNA base modifications and strand breaks, the DNA damage response has not been adequately investigated. We have investigated the effect of hyperoxia on DNA damage signaling and show that hyperoxia is a unique stress that activates the ataxia telangiectasia mutant (ATM)- and Rad3-related protein kinase (ATR)-dependent p53 phosphorylations (Ser6, -15, -37, and -392), phosphorylation of histone H2AX (Ser139), and phosphorylation of checkpoint kinase 1 (Chk1). In addition, we show that phosphorylation of p53 (Ser6) and histone H2AX (Ser139) depend on both ATM and ATR. We demonstrate that ATR activation precedes ATM activation in hyperoxia. Finally, we show that ATR is required for ATM activation in hyperoxia. Taken together, we report that ATR is the major DNA damage signal transducer in hyperoxia that activates ATM.

Topics: Adaptor Proteins, Signal Transducing; Adenocarcinoma; Apoptosis; Ataxia Telangiectasia Mutated Proteins; Casein Kinase II; Cell Cycle Proteins; Cell Line, Tumor; Checkpoint Kinase 1; DNA Repair; DNA-Binding Proteins; Histones; Humans; Hyperoxia; Lung Neoplasms; Phosphorylation; Protein Kinases; Protein Serine-Threonine Kinases; RNA Interference; Serine; Signal Transduction; Tumor Suppressor Protein p53; Tumor Suppressor Proteins

The androgen receptor (AR) mediates the biological responses of androgens in the prostate gland. In prostate cancer, this pathway is often deregulated and causes an uncontrolled proliferation.. The current study focuses on the effects of an inhibition of protein kinase CK2 on the AR-mediated transcription in LNCaP prostate cancer cells. We used chemical inhibitors of CK2 as well as dominant-negative kinase mutants to downregulate the CK2 activity. We determined the effects of the inhibition by Western blot analysis of endogenous target genes of the AR as well as by reporter assays.. We found that inhibition of CK2 led to a downregulation of the AR-dependent transcription. Moreover, the amount of the AR protein decreased significantly.. According to the fact that AR pathways are involved in the development and progression of prostate cancer, the ability to modulate AR function should provide an alternative basis for the development of new cancer therapies.

Topics: Adenocarcinoma; Benzimidazoles; Blotting, Western; Casein Kinase II; Cell Line, Tumor; Dose-Response Relationship, Drug; Down-Regulation; Emodin; Genes, Reporter; Humans; Male; Prostate-Specific Antigen; Prostatic Neoplasms; Protein Kinase Inhibitors; Receptors, Androgen; Transcription, Genetic; Transfection

Exposure to and bioaccumulation of lipophilic environmental pollutants, such as polycyclic aromatic hydrocarbons (PAHs), has been implicated in breast cancer. Treatment of female rats with the prototypic xenobiotic PAH 7,12-dimethylbenz(a)anthracene (DMBA) induces mammary tumors with an invasive phenotype. Here, we show that green tea prevents or reverses loss of the epithelial marker E-cadherin on the surface of DMBA-induced in situ cancers. To investigate the mechanism(s) leading to a less invasive phenotype, the effects of the green tea polyphenol epigallocatechin-3 gallate (EGCG) on mammary tumor cells were assessed. EGCG reversed epithelial to mesenchymal transition (EMT) in DMBA-treated NF-kappaB c-Rel-driven mammary tumor cells and reduced levels of c-Rel and the protein kinase CK2. Ectopic coexpression of c-Rel and CK2alpha in untransformed mammary epithelial cells was sufficient to induce a mesenchymal gene profile. Mammary tumors and cell lines derived from MMTV-c-Rel x CK2alpha bitransgenic mice displayed a highly invasive phenotype. Coexpression of c-Rel and CK2, or DMBA exposure induced the aryl hydrocarbon receptor (AhR) and putative target gene product Slug, an EMT master regulator, which could be reversed by EGCG treatment. Thus, activation of c-Rel and CK2 and downstream targets AhR and Slug by DMBA induces EMT; EGCG can inhibit this signaling.

Topics: 9,10-Dimethyl-1,2-benzanthracene; Adenocarcinoma; Animals; Beverages; Carcinoma in Situ; Casein Kinase II; Female; Flavonoids; Mammary Neoplasms, Animal; Neoplasm Invasiveness; Phenols; Phenotype; Polyphenols; Proto-Oncogene Proteins c-rel; Rats; Rats, Sprague-Dawley; Snail Family Transcription Factors; Transcription Factors

Protein kinase casein kinase II (CK2) is increased in response to diverse growth stimuli, as well as being elevated in many human cancers examined. We have demonstrated that CK2 is a key survival factor that protects human colon carcinoma cells from TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis. We determined that inhibition of CK2 phosphorylation events by DRB (5,6-dichlorobenzimidazole) resulted in dramatic sensitization of tumor cells to TRAIL-induced apoptosis, in the absence of effects in normal cells. Sensitization was caspase dependent, and independent of regulation via NF-kappaB. Further, inhibition of phosphorylation by CK2 did not modify the expression level of antiapoptotic proteins. Analysis of TRAIL-induced death-inducing signaling complex (DISC) formation demonstrated enhanced formation of the DISC, enhanced cleavage of caspase-8 and cleavage of Bid in the presence of DRB, thereby facilitating the release of proapoptotic factors from the mitochondria with subsequent downregulation of the expression of XIAP and c-IAP1. Further, silencing of CK2alpha in HT29 cells following transfection of CK2alpha shRNA abrogated CK2 kinase activity while simultaneously increasing TRAIL sensitivity. These findings demonstrate that CK2 plays a critical antiapoptotic role by conferring resistance to TRAIL at the level of the DISC.

Topics: Adenocarcinoma; Apigenin; Apoptosis; Apoptosis Regulatory Proteins; Casein Kinase II; Cell Death; Cell Line, Tumor; Colonic Neoplasms; Death Domain Receptor Signaling Adaptor Proteins; Enzyme Inhibitors; Genetic Vectors; Humans; Indoles; Kinetics; Maleimides; Membrane Glycoproteins; Receptors, Tumor Necrosis Factor; Recombinant Proteins; TNF-Related Apoptosis-Inducing Ligand; Transfection; Tumor Necrosis Factor-alpha

Tumor-cell death can be triggered by engagement of specific death receptors with Apo2 ligand/tumor necrosis factor-related apoptosis-inducing ligand (Apo2L/TRAIL). Apo2L/TRAIL-induced apoptosis involves caspase-8-mediated cleavage of BID. The active truncated form of BID (tBID) triggers the mitochondrial activation of caspase-9 by inducing the activation of BAK or BAX. Although a broad spectrum of human cancer cell lines express death receptors for Apo2L/TRAIL, many remain resistant to TRAIL/Apo2L-induced death. A variety of human cancers exhibit increased activity of casein kinase II (CK2). Here we demonstrate that CK2 is at the nexus of two signaling pathways that protect tumor cells from Apo2L/TRAIL-induced apoptosis. We find that CK2 inhibits Apo2L/TRAIL-induced caspase-8-mediated cleavage of BID, thereby reducing the formation of tBID. In addition, CK2 promotes nuclear factor kappa B (NF-kappa B)-mediated expression of Bcl-x(L), which sequesters tBID and curtails its ability to activate BAX. Tumor cells with constitutive activation of CK2 exhibit a high Bcl-x(L)/tBID ratio and fail to activate caspase-9 or undergo apoptosis in response to Apo2L/TRAIL. Conversely, reduction of the Bcl-x(L)/tBID ratio by inhibition of CK2 renders such cancer cells sensitive to Apo2L/TRAIL-induced activation of caspase-9 and apoptosis. Using isogenic cancer cell lines that differ only in the presence or absence of either the p53 tumor suppressor or the BAX gene, we show that the enhancement of Apo2L/TRAIL-induced tumor-cell death by CK2 inhibitors requires BAX, but not p53. The identification of CK2 as a key survival signal that protects tumor cells from death-receptor-induced apoptosis could aid the design of Apo2L/TRAIL-based combination regimens for treatment of diverse cancers.

Topics: Adenocarcinoma; Antineoplastic Agents; Apoptosis; Apoptosis Regulatory Proteins; bcl-2-Associated X Protein; bcl-X Protein; BH3 Interacting Domain Death Agonist Protein; Breast Neoplasms; Carrier Proteins; Casein Kinase II; CASP8 and FADD-Like Apoptosis Regulating Protein; Colonic Neoplasms; Drug Synergism; Humans; Intracellular Signaling Peptides and Proteins; Membrane Glycoproteins; NF-kappa B; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-bcl-2; Recombinant Proteins; TNF-Related Apoptosis-Inducing Ligand; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha; Tumor Suppressor Protein p53

Protein kinase CK2 (CK2) has long been implicated in the regulation of cell growth and proliferation. Its activity is generally elevated in rapidly proliferating tissues, and nuclear matrix (NM) is an important subnuclear locale of its functional signaling. In the prostate, nuclear CK2 is rapidly lost commensurate with induction of receptor-mediated apoptosis after growth stimulus withdrawal. By contrast, chemical-induced apoptosis in prostate cancer and other cells (by etoposide and diethylstilbestrol) evokes an enhancement in CK2 associated with the NM that appears to be because of translocation of CK2 from the cytoplasmic to the nuclear compartment. This shuttling of CK2 to the NM may reflect a protective response to chemical-mediated apoptosis. Supporting evidence for this was obtained by employing cells that were transiently transfected with various expression plasmids of CK2 (thereby expressing additional CK2) prior to treatment with etoposide or diethylstilbestrol. Cells transfected with the CK2alpha or CK2alphabeta showed significant resistance to chemical-mediated apoptosis commensurate with the corresponding elevation in CK2 in the NM. Transfection with CK2beta did not demonstrate this effect. These results suggest, for the first time, that besides the commonly appreciated function of CK2 in cell growth, it may also have a role in protecting cells against apoptosis.

Topics: Adenocarcinoma; Animals; Apoptosis; Casein Kinase II; Catalytic Domain; Cell Compartmentation; Cytoprotection; Cytosol; Diethylstilbestrol; DNA, Neoplasm; Etoposide; Female; Humans; Male; Mammary Neoplasms, Animal; Mice; Nuclear Matrix; Prostatic Neoplasms; Protein Serine-Threonine Kinases; Protein Transport; Recombinant Proteins; Subcellular Fractions

Protein kinase CK2 is a ubiquitous and evolutionarily conserved serine/threonine kinase that is upregulated in many human cancers and can serve as an oncogene in lymphocytes. Recently, we have demonstrated that CK2 potentiates Wnt/beta-catenin signaling in mammary epithelial cells. To determine whether CK2 overexpression contributes to mammary tumorigenesis, we have performed comparative studies of human and rat breast cancer specimens and we have engineered transgenic mice with dysregulated expression of CK2alpha in the mammary gland. We find that CK2 is highly expressed in human breast tumor specimens and in carcinogen-induced rat mammary tumors. Overexpression of CK2alpha in the mammary gland of transgenic mice, under control of the MMTV-LTR, causes hyperplasia and dysplasia of the female mammary gland. Thirty per cent of the female MMTV-CK2alpha transgenic mice develop mammary adenocarcinomas at a median of 23 months of age, often associated with Wnt pathway activation, as evidenced by upregulation of beta-catenin protein. NF-kappaB activation and upregulation of c-Myc also occur frequently. Thus, in mice, rats, and humans, dysregulated expression of CK2 is associated with and is capable of contributing to mammary tumorigenesis. Targeted inhibition of CK2 could be useful in the treatment of breast cancer.

Topics: Adenocarcinoma; Age of Onset; Animals; beta Catenin; Breast Neoplasms; Casein Kinase II; Cell Transformation, Neoplastic; Cytoskeletal Proteins; Female; Fibrocystic Breast Disease; Humans; Hyperplasia; Lactation; Mammary Glands, Animal; Mammary Neoplasms, Animal; Mammary Tumor Virus, Mouse; Mice; Mice, Transgenic; NF-kappa B; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-myc; Signal Transduction; Trans-Activators; Wnt Proteins; Zebrafish Proteins

Protein P1, which is a nuclear protein resembling high mobility group proteins, has been studied in human breast adenocarcinomas and compared to those from control tissue. The presence of the protein was confirmed by in vitro phosphorylation by casein kinase II and immunoblotting, using antibodies raised in rabbits against rat liver P1. The protein has been isolated by reverse phase HPLC chromatography which provides a more rapid method of purification requiring smaller amounts of material. The levels of P1 expression were investigated and it was found that there was a three-fold increase in the ratio of P1/histone H1 in normal breast tissue as compared to the neoplastic tissue. In two other malignant and non-malignant tissues studied, the level of P1 was also decreased in the malignant tissues. Thermolytic phosphopeptides of P1 from normal and malignant human breast tissues exhibited the same pattern, though when compared to the phosphopeptide pattern from rat tissue, differences were observed.

Topics: Adenocarcinoma; Amino Acids; Animals; Blotting, Western; Breast Neoplasms; Casein Kinase II; Cell Cycle Proteins; Chromatography, High Pressure Liquid; Densitometry; DNA-Binding Proteins; Electrophoresis, Polyacrylamide Gel; Female; HeLa Cells; High Mobility Group Proteins; Histones; Humans; Image Processing, Computer-Assisted; In Vitro Techniques; Minichromosome Maintenance Complex Component 3; Molecular Weight; Nuclear Proteins; Phosphopeptides; Phosphorylation; Protein Serine-Threonine Kinases; Rabbits; Transcription Factors

Breast cancer is a major cause of cancer death in women, and the genetic abnormalities leading to the common sporadic forms of the disease are still under active investigation. CK2 has been reported to be upregulated in human breast cancer, which these studies confirm; CK2 is also upregulated in rat carcinogen-induced breast tumors. Transgenic mice overexpressing CK2alpha in the mammary gland develop mammary hyperplasia, dysplasia, and eventually adenocarcinomas, demonstrating that dysregulated expression of CK2 can contribute to transformation of the mammary epithelium. These mammary tumors have evidence of activation of the Wnt and NFkappaB pathways and upregulation of c-Myc. CK2 is capable of phosphorylating the key signaling molecule in the Wnt pathway, the transcriptional cofactor beta-catenin, and regulating its turnover. CK2 is known to phosphorylate IkappaB and thereby regulate basal NFkappaB levels; in the mammary cell lines and tumors, CK2 activity correlates with NFkappaB levels and inhibition of CK2 downregulates NFkappaB. Thus, CK2 may promote breast cancer through dysregulation of key pathways of transcriptional control in the mammary epithelium, and inhibition of CK2 has a potential role in the treatment of breast and other cancers.

Topics: Adenocarcinoma; Animals; Apigenin; Blotting, Western; Breast Neoplasms; Casein Kinase II; DNA, Complementary; Dose-Response Relationship, Drug; Down-Regulation; Flavonoids; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Neoplastic; Genes, Reporter; Humans; Immunohistochemistry; Mammary Neoplasms, Animal; Mice; Mice, Transgenic; Neoplasms, Experimental; NF-kappa B; Phosphorylation; Precipitin Tests; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-myc; Rats; Signal Transduction; Time Factors; Transcription, Genetic; Up-Regulation; Wnt Proteins; Zebrafish Proteins

Protein kinase CK2, a messenger-independent serine/threonine kinase, has been implicated in cell growth. Androgenic stimulus in rat prostate modulates its association with nuclear matrix (NM) and chromatin. Because the growth of human prostate carcinoma cells is influenced by androgens and/or growth factors, we determined the nature of CK2 signaling in the NM in response to androgen and growth factor stimuli. Androgen-sensitive LNCaP and androgen-insensitive PC-3 cells were cultured in media to regulate their growth in the presence of 5alpha-dihydrotestosterone (5alpha-DHT) or growth factors (epidermal growth factor, keratinocyte growth factor, and transforming growth factor alpha). The activity of CK2 was measured in the cytosolic and NM fractions isolated from these cells after treatment with growth stimuli. The changes in CK2 in various fractions were also confirmed by immunoblotting with a specific antibody. LNCaP cells responded to both 5alpha-DHT and growth factors for growth. The presence of these agents in the culture medium evoked a translocation of CK2 to the NM from the cytosol. The PC-3 cells did not respond to 5alpha-DHT for growth but did respond to growth factors. Under these conditions, there was also a translocation of CK2 to the NM concomitant with a decrease in the cytosolic fraction. These results suggest that CK2 translocation to the NM occurs in response to various growth stimuli in cells in culture. Thus, CK2 is a common downstream signal transducer in response to diverse growth stimuli that may relate to the pathobiology of prostate cancer cells.

Topics: Adenocarcinoma; Animals; Casein Kinase II; Cell Division; Chromatin; Cytosol; Dihydrotestosterone; DNA-Binding Proteins; Epidermal Growth Factor; Fibroblast Growth Factor 10; Fibroblast Growth Factor 7; Fibroblast Growth Factors; Growth Substances; Humans; Kinetics; Male; Nuclear Matrix; Prostatic Neoplasms; Protein Serine-Threonine Kinases; Rats; Signal Transduction; Transforming Growth Factor alpha; Tumor Cells, Cultured

Butyrate, a dietary fiber derivative, is a well-known differentiating agent in cultured cell lines. In addition, its antineoplastic activity toward colon-rectum cancers has been documented both in vivo and in vitro. Despite the large amount of information on the potential clinical efficacy of butyrate, its mechanism of action at the molecular level has only been partially investigated. Here, we show that serine/threonine protein kinase CKII is a target of butyrate activity. In the human adenocarcinoma cell line, HT29, treated with 2 mM sodium butyrate, CKII activity decreases 50% at 24 and 48 hours after drug addition. The enzyme down-regulation is not due to changes in protein amount since the levels of the different CKII subunits remain constant during butyrate treatment. The data reported provide the first evidence that CKII down-regulation is involved in the signal transduction pathway started by butyrate.

Topics: Adenocarcinoma; Amino Acid Sequence; Butyrates; Butyric Acid; Casein Kinase II; Cell Differentiation; Colonic Neoplasms; Down-Regulation; Enzyme Inhibitors; Humans; Oligopeptides; Protein Serine-Threonine Kinases; Signal Transduction; Substrate Specificity; Tumor Cells, Cultured