The Preeclamptic Environment Promotes the Activation of Transcription Factor Kappa B by P53/RSK1 Complex in a HTR8/SVneo Trophoblastic Cell Line.

Preeclampsia is a pregnancy disorder associated with shallow placentation, forcing placental cells to live in hypoxic conditions. This activates the transcription factor kappa B (NFκB) in maternal and placental cells. Although the role of NFκB in preeclampsia is well documented, its mechanism of activation in trophoblastic cells has been never studied. This study investigates the mechanism of NFκB activation in a first trimester trophoblastic cell line (HTR8/SVneo) stimulated by a medium containing serum from preeclamptic (PE) or normotensive (C) women in hypoxic (2% O2) or normoxic (8% O2) conditions. The results indicate that in HTR8/SVneo cells, the most widely studied NFκB pathways, i.e., canonical, non-canonical and atypical, are downregulated in environment PE 2% O2 in comparison to C 8% O2. Therefore, other pathways may be responsible for NFκB activation. One such pathway depends on the activation of NFκB by the p53/RSK1 complex through its phosphorylation at Serine 536 (pNFκB Ser536). The data generated by our study show that inhibition of the p53/RSK1 pathway by p53-targeted siRNA results in a depletion of pNFκB Ser536 in the nucleus, but only in cells incubated with PE serum at 2% O2. Thus, the p53/RSK1 complex might play a critical role in the activation of NFκB in trophoblastic cells and preeclamptic placentas.

Canonical, Non-Canonical and Atypical Pathways of Nuclear Factor кb Activation in Preeclampsia.

Although higher nuclear factor κB (NFκB) expression and activity is observed in preeclamptic placentas, its mechanism of activation is unknown. This is the first study to investigate whether the canonical, non-canonical, or atypical NFκB activation pathways may be responsible for the higher activation of NFκB observed in preeclamptic placentas. The study included 268 cases (130 preeclamptic women and 138 controls). We studied the expression of the genes coding for NFκB activators (NIK, IKKα, IKKß, and CK2α) and inhibitors (IκBα and IκBß) using RT-PCR in real time. The RT-PCR results were verified on the protein level using ELISA and Western blot. To determine the efficiency of the pathways, the ratios of activator(s) to one of the inhibitors (IκBα or IκBß) were calculated for each studied pathway. The preeclamptic placentas demonstrated significantly lower IKKα and CK2α but higher IκBα and IκBß protein levels. In addition, the calculated activator(s) to inhibitor (IκBα or IκBß) ratios suggested that all studied pathways might be downregulated in preeclamptic placentas. Our results indicate that preeclamptic placentas may demonstrate mechanisms of NFκB activation other than the canonical, non-canonical, and atypical forms. In these mechanisms, inhibitors of NFκB may play a key role. These observations broaden the existing knowledge regarding the molecular background of preeclampsia development.

Placental Expression of NEMO Protein in Normal Pregnancy and Preeclampsia.

BACKGROUND: Preeclamptic pregnancies often present an intensified inflammatory state associated with the nuclear activity of NFκB. NEMO is an essential regulator of nuclear factor kappa B (NFκB) in cytoplasmic and nuclear cellular compartments. The aim of the present study is to examine the level and localization of the NEMO protein in preeclamptic and nonpreeclamptic placentas. METHODS: The study includes 97 preeclamptic cases and 88 controls. NEMO distribution was analyzed immunohistochemically. Its localization in the nuclear and cytoplasmic fractions, as well as in total homogenates of placental samples, was studied by western blot and ELISA. RESULTS: The western blot and ELISA results indicate a significant difference in NEMO concentration in the total and nuclear fractions between preeclamptic and control samples (p < 0.01 and p < 0.001, respectively). In the cytoplasmic complement, similar levels of NEMO were found in preeclamptic and control placentas. In addition, immunohistochemical staining revealed that the NEMO protein is mainly localized in the syncytiotrophoblast layer, with controls demonstrating a stronger reaction with NEMO antibodies. This study also shows that the placental level of NEMO depends on the sex of the fetus. CONCLUSIONS: The depletion of the NEMO protein in the cellular compartments of placental samples may activate one of the molecular pathways influencing the development of preeclampsia, especially in pregnancies with a female fetus. A reduction of the NEMO protein in the nuclear fraction of preeclamptic placentas may intensify the inflammatory state characteristic for preeclampsia and increase the level of apoptosis and necrosis within preeclamptic placentas.

Silencing of angiotensin receptor 1 interferes with angiotensin II oncogenic activity in endometrial cancer.

In mammalian cells, angiotensin II (AngII) binds to 2 distinct high-affinity plasma membrane receptors: angiotensin receptor 1 (AT1R) and angiotensin receptor 2 (AT2R). Healthy human endometrium from women of reproductive age expresses all of the components of the renin-angiotensin system. Many studies suggest that AngII, acting via AT1R, may have a role in the development and progression of cancer, which changes the expression of angiogenic factors, AngII and AT1R are correlated with the presence of endometrial cancer (EC). The aim of the current study was to identify the effects of AngII on the proliferation, cell cycle progression, apoptosis and mobility of ISHIKAWA, MFE296 and MFE280 EC cells with silenced AT1R. It also examines epithelial-mesenchymal transition markers by gene expression analysis. The obtained results suggest that the silencing of AT1R expression alters the migration and invasion ability of EC cells. However, this silencing is not sufficient to inhibit the effects of AngII on EC cells, suggesting that AngII plays a more complex role in the development of EC.

Lower levels of Caveolin-1 and higher levels of endothelial nitric oxide synthase are observed in abdominal aortic aneurysm patients treated with simvastatin.

This study was undertaken to verify whether simvastatin modulates Cav-1/eNOS expression, and if this modulation is associated with changes in pro- and anti-inflammatory cytokine and Toll-like receptor 4 (TLR4) level in abdominal aortic aneurysm (AAA). It is a 1:2 case-control study of non-statin (n=12) and simvastatin-treated patients (n=24) who underwent open AAA repair. Simvastatin treatment decreased Cav-1 (p<0.05) and increased eNOS expression (p<0.01) in the AAA wall. These changes might be dose dependent. The changes in Cav-1 and eNOS were associated with a trend towards decreased IL-6 and IL-17 concentration (p>0.05) and increased IL-10 concentration (p=0.055); however, TLR4 expression was unaffected, suggesting that simvastatin influences Cav-1 and eNOS in the AAA wall by other mechanisms. Simvastatin may modulate Cav-1 and eNOS expression in the aneurysmal wall, indicating a potentially beneficial role for statins in AAA patients.

Synthesis, Biological Activity and Preliminary in Silico ADMET Screening of Polyamine Conjugates with Bicyclic Systems.

Polyamine conjugates with bicyclic terminal groups including quinazoline, naphthalene, quinoline, coumarine and indole have been obtained and their cytotoxic activity against PC-3, DU-145 and MCF-7 cell lines was evaluated in vitro. Their antiproliferative potential differed markedly and depended on both their chemical structure and the type of cancer cell line. Noncovalent DNA-binding properties of the most active compounds have been examined using ds-DNA thermal melting studies and topo I activity assay. The promising biological activity, DNA intercalative binding mode and favorable drug-like properties of bis(naphthalene-2-carboxamides) make them a good lead for further development of potential anticancer drugs.

A common effect of angiotensin II and relaxin 2 on the PNT1A normal prostate epithelial cell line

The prostate gland is a part of the male reproductive tract which produces both angiotensin II (Ang II) and relaxin 2 (RLN2). The present study analyzes the effect of both these peptide hormones at concentration 10−8M on viability, proliferation, adhesion, migration, and invasion of normal prostate epithelial cells (PNT1A). Improved survival in two- and three-dimensional cell cultures was noted as well as visual changes in colony size and structure in Geltrex™. Stimulatory influence on cell viability of each peptide applied single was lower than in combination. Enhanced survival of PNT1A cells appears to be associated with increased BCL2/BAX messenger RNA (mRNA) expression ratio. Modulation of cell spreading and cell-extracellular matrix adhesion dynamics were also altered as an influence of tested hormone application. However, long-term Ang II and RLN2 effects may lead to an increase of normal prostate cell migration and invasion abilities. Moreover, gelatin zymography revealed that both gelatinases A and B were augmented by Ang II treatment, whereas RLN2 significantly stimulated only MMP-9 secretion. These results support the hypothesis that deregulation of locally secreted peptide hormones such as Ang II and RLN2 may take part in the development of certain cancers, including prostate cancer. Moreover, the observed ability of relaxin 2 to act as a regulator of mRNA expression levels not only LGR7 but also classic angiotensin receptors suggested that renin-angiotensin system and relaxin family peptide system are functionally linked (AU)

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Angiotensin II promotes endometrial cancer cell survival.

Endometrial cancer (EC) is one of the most common female cancers. One of the key processes involved in EC development is uncontrolled proliferation stimulated by local factors such as angiotensin. The aim of the present study was to evaluate the influence of angiotensin II (Ang II) on human EC cells. Biological assays and gene expression analysis were performed on three cell lines: ISH, MFE-296 and MFE-280. Our results indicated that at the beginning of cancerogenesis Ang II induced abnormal proliferation at lower doses. We also showed that dose-dependent induction of proliferation was connected with changes in the expression of MKI67, CCND1 and CCNE1 genes in well- and poorly differentiated cancer cells. After Ang II treatment, poorly differentiated endometrial cancer cell line acquired a mesenchymal phenotype, which was characterized by induced expression of EMT-related genes (VIM, CD44, SNAI1, ZEB1 and ZEB2). Our study revealed that Ang II influences EC cells in terms of cancer-related processes, and is responsible for increased proliferation, reduction in apoptosis, increased mobility and modulation of adhesion potential. Its effect and effectiveness appear to be highly connected with the differentiation status of the cancerous cells, as Ang II appears to play a crucial role in the early and late stages of malignant transformation.

Coexpression of CAV-1, AT1-R and FOXM1 in prostate and breast cancer and normal cell lines and their influence on metastatic properties.

The aim of this study was to evaluate the coexpression of caveolin-1 (CAV-1), angiotensin II type 1 receptor (AT1-R) and forkhead box Ml (FOXM1) in prostate and breast cancer cell lines, in comparison with normal cell lines. CAV-1, AT1-R and FOXM1 expression was determined by reverse transcription-quantitative polymerase chain reaction and western blot analysis in the prostate cancer cell lines PC3, DU145 and LNCaP; prostate normal cell line PNT1A; breast cancer cell lines MCF-7 and MDA-MB-231; and the normal breast cell line 184A1. A correlation between the expression levels of the investigated genes and their metastatic properties was determined by the Spearman's rank test (P<0.05) and Aspin-Welsch t-test, respectively. In prostate cell lines, a significant correlation was noted between CAV-1 and AT1-R expression and between FOXM1 and CAV-1 expression. A correlation between the expression levels of the investigated genes and their metastatic potential was also observed, with relatively high expression of all the investigated genes in the normal prostate cell line PNT1A. In comparison to prostate cancer cell lines, an adverse dependency between CAV-1, AT1-R, FOXM1 expression and metastatic potential was observed in the breast cancer cell lines. Relatively high expression of all tested genes was observed in the normal breast cell line 184A1, which was decreasing respectively with increasing metastatic potential of breast cancer cell lines. The results obtained here indicate that CAV-1, FOXM1 and AT1-R may be potential markers of tumorigenesis in certain types of cancer in vitro.

A common effect of angiotensin II and relaxin 2 on the PNT1A normal prostate epithelial cell line.

The prostate gland is a part of the male reproductive tract which produces both angiotensin II (Ang II) and relaxin 2 (RLN2). The present study analyzes the effect of both these peptide hormones at concentration 10(-8)M on viability, proliferation, adhesion, migration, and invasion of normal prostate epithelial cells (PNT1A). Improved survival in two- and three-dimensional cell cultures was noted as well as visual changes in colony size and structure in Geltrex™. Stimulatory influence on cell viability of each peptide applied single was lower than in combination. Enhanced survival of PNT1A cells appears to be associated with increased BCL2/BAX messenger RNA (mRNA) expression ratio. Modulation of cell spreading and cell-extracellular matrix adhesion dynamics were also altered as an influence of tested hormone application. However, long-term Ang II and RLN2 effects may lead to an increase of normal prostate cell migration and invasion abilities. Moreover, gelatin zymography revealed that both gelatinases A and B were augmented by Ang II treatment, whereas RLN2 significantly stimulated only MMP-9 secretion. These results support the hypothesis that deregulation of locally secreted peptide hormones such as Ang II and RLN2 may take part in the development of certain cancers, including prostate cancer. Moreover, the observed ability of relaxin 2 to act as a regulator of mRNA expression levels not only LGR7 but also classic angiotensin receptors suggested that renin-angiotensin system and relaxin family peptide system are functionally linked.

Diverse effect of WWOX overexpression in HT29 and SW480 colon cancer cell lines.

WW-domain-containing oxidoreductase (WWOX) is the tumour suppressor gene from the common fragile site FRA16D, whose altered expression has been observed in tumours of various origins. Its suppressive role and influence on basic cellular processes such as proliferation and apoptosis have been confirmed in many in vitro and in vivo studies. Moreover, its protein is thought to take part in the regulation of tissue morphogenesis and cell differentiation. However, its role in colon cancer formation remains unclear. The aim of this study was to characterize the influence of WWOX on the process of colon cancerogenesis, the basic features of the cancer cell and its expression profiles. Multiple biological tests, microarray experiments and quantitative reverse transcriptase (RT)-PCR were performed on two colon cancer cell lines, HT29 and SW480, which differ in morphology, expression of differentiation markers, migratory characteristics and metastasis potential and which represent negative (HT29) and low (SW480) WWOX expression levels. The cell lines were subjected to retroviral transfection, inducting WWOX overexpression. WWOX was found to have diverse effects on proliferation, apoptosis and the adhesion potential of modified cell lines. Our observations suggest that in the HT29 colon cancer cell line, increased expression of WWOX may result in the transition of cancer cells into a more normal colon epithelium phenotype, while in SW480, WWOX demonstrated well-known tumour suppressor properties. Our results also suggest that WWOX does not behave as classical tumour suppressor gene, and its influence on cell functioning is more global and complicated.

Correlation between VEGFR-2 receptor kinase domain-containing receptor (KDR) mRNA and angiotensin II receptor type 1 (AT1-R) mRNA in endometrial cancer.

PURPOSE: Angiogenesis, a multistep process that results in new blood vessel formation from preexisting vasculature is essential for both the growth of solid tumour and for metastasis. Stimulation of vascular endothelial growth factor receptor (VEGFR), a transmembrane glycoprotein, results in mitogenesis. Within this family of receptors, VEGFR 2/kinase-insert-domain containing receptor appears to be principally upregulated during tumorigenesis. The aim of this study was to determine the expression of VEGFR-2/kinase-insert-domain containing receptor (KDR) and its correlation with angiotensin receptor type 1 (AT1-R) and clinical factors in endometrial carcinoma. METHODS: The expression of KDR and AT1-R was studied in endometrial carcinoma and normal endometrium by Real-time RT-PCR and Western blot analysis in 136 samples. The expression profile was correlated with the clinicopathological characteristics of endometrial adenocarcinoma. RESULTS: We noted a significant correlation between the expression of KDR and AT1-R in tumour grade G1, G2 and G3 (R(s)=0.50; p=0.002, R(s)=0.69; p=0.0001, R(s)=0.52; p=0.005, respectively). In stage I and stage II carcinoma, a significant correlation was also found between the expression of KDR and AT1-R (R(s)=0.70, p=0.0001, R(s)=0.67; p=0.001, respectively). Moreover significant correlation was observed between both KDR and AT1-R in tissue with different myometrial invasion (R(s)=0.54, p=0.0001, R(s)=0.68; p=0.0001; respectively for tumours with invasion into the inner half and invasion into the outer half). CONCLUSIONS: Basing on received correlation between AT1-R and KDR expression and previous results we speculate that angiotensin through AT1-R modulates KDR expression and thus have influence on local VEGF level. However, further studies are required to clarify the biological interaction between KDR, AT1-R and other hormonal regulators in endometrial carcinoma.

A comparison of the effects of Angiotensin IV on androgen-dependent and androgen-independent prostate cancer cell lines.

INTRODUCTION: Angiotensin IV is one of the biologically active peptides of the renin-angiotensin system. Limited data suggests that this hexapeptide could contribute to cancer development and/or progression. MATERIALS AND METHODS: Using the MTT reduction assay as an indicator of cell viability, and the bromodeoxyuridine incorporation assay as an indicator of cell proliferation, the influence of Angiotensin IV was evaluated on two human prostate cancer lines: androgen-dependent (LNCaP) and androgen-independent (DU-145). The potential effect of Angiotensin IV classic angiotensin receptors was examined by using the selective antagonists losartan and PD123319. Finally, the changes in expression levels of AT1 and AT2 receptors were compared, before and after angiotensin treatment. RESULTS: Angiotensin IV caused significant changes in cell viability and proliferation in LNCaP cells but not in DU-145. It was found that AT2 receptor blocker (PD123319) was able to diminish the suppressor effect of Angiotensin IV on bromodeoxyuridine incorporation into the DNA of androgen-dependent prostate cancer cells. Simultaneously, it was reported that Angiotensin IV is the factor that modulates the density of AT1 and AT2 receptors in prostate cancer cells. CONCLUSIONS: These findings suggested that Angiotensin IV can modulate tumour cell proliferation in the early stage of androgen-dependent prostate cancer. The effect might be promoted by the change of the angiotensin receptor level.

Influence of myocardial infarction on changes in the expression of angiotensin type 1 receptor in the rat prostate.

Angiotensin II (AngII) is the biologically active peptide of the renin-angiotensin system (RAS). Tissue- based, local RAS has been identified in the prostate, testis, epididymis and coagulating glands. Experimental and clinical studies have consistently shown that myocardial infarction (MI) is associated with activation of the systemic RAS with increased concentration of angiotensin peptides in the blood and changes in expression of angiotensin receptors (AT). Changes in angiotensin receptors in the renal and cardiovascular system after MI are well recognized, but the effects of MI influence on changes in other tissue like the prostate gland are unknown. In the present study, we investigated the effect of myocardial infarction on angiotensin receptor protein and mRNA expression in the rat prostate gland. MI model was established in Wistar rats by ligating the left coronary artery (modified Selye method). The levels of AT1a-b and AT2 receptor mRNAs and proteins were measured in the rat prostate. Our study demonstrates tissue-specific changes in AT1a-b and AT2 receptor expression after myocardial infarction. The results show that MI has a strong influence on the expression of angiotensin receptor type AT1 in the prostate at the protein and mRNA level.