23 results on '"Creswell, Karen"'
Search Results
2. Comparison of tumor growth assessment using GFP fluorescence and DiI labeling in a zebrafish xenograft model.
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Dryer, Yaal, Berghausen, Joos, Creswell, Karen, Glasgow, Eric, and Brelidze, Tinatin I.
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TUMOR growth ,FLUORESCENCE ,BRACHYDANIO ,GREEN fluorescent protein ,FLUORESCENT dyes - Abstract
DiI is a lipophilic fluorescent dye frequently used to label and trace cells in cell cultures and xenograft models. However, DiI can also transfer from labeled to unlabeled cells, including host organism cells, and label dead cells obscuring interpretation of the results. These limitations of DiI labeling in xenograft models have not been thoroughly investigated. Here we labeled green fluorescent protein (GFP)- expressing MDA-MB-231 cells with DiI to directly compare tumor growth assessment in zebrafish xenografts using the DiI labeling and GFP fluorescence. Our results indicate that the DiI based assessment significantly overestimated tumor growth in zebrafish xenograft models compared to the GFP fluorescence based assessment. The imaging of DiI labeled GFP-expressing MDA-MB-231 cell cultures indicated that the DiI labeling of the membrane is uneven. Analysis of the DiI labeled GFP-expressing MDA-MB-231 cell cultures with flow cytometry indicated that the DiI labeling varied over time while the GFP fluorescence remained unchanged, suggesting that the GFP fluorescence is a more reliable signal for monitoring tumor progression than the DiI labeling. Taken together, our results demonstrate limitations of using DiI labeling for xenograft models and emphasize the need for validating the results based on DiI labeling with other orthogonal methods, such as the ones utilizing genetically encoded fluorophores. [ABSTRACT FROM AUTHOR]
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- 2023
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3. Loss of RARRES1 function Promotes Follicular Lymphomagenesis and Inhibits B cell Differentiation in Mice.
- Author
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Patel, Jay, Dan Xun, Creswell, Karen, Kim, Daniel K., Wu, Matthew, Jung-Won Hwang, Kim, Taylor S., Bansal, Shivani, Sung-Hyeok Hong, Galli, Susana, Hyun-Jung Kim, Chuxia Deng, Byers, Stephen W., and Mi-Hye Lee
- Published
- 2022
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- View/download PDF
4. Phase I/II study of sorafenib with anastrozole in patients with hormone receptor positive aromatase inhibitor resistant metastatic breast cancer
- Author
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Isaacs, Claudine, Herbolsheimer, Pia, Liu, Minetta C., Wilkinson, Mary, Ottaviano, Yvonne, Chung, Gina G., Warren, Robert, Eng-Wong, Jennifer, Cohen, Philip, Smith, Karen L., Creswell, Karen, Novielli, Antonella, and Slack, Rebecca
- Published
- 2011
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5. Dopamine 5 receptor mediates Ang II type 1 receptor degradation via a ubiquitin-proteasome pathway in mice and human cells
- Author
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Li, Hewang, Armando, Ines, Yu, Peiying, Escano, Crisanto, Mueller, Susette C., Asico, Laureano, Pascua, Annabelle, Lu, Quansheng, Wang, Xiaoyan, Villar, Anthony M. Van, Jones, John E., Wang, Zheng, Periasamy, Ammasi, Lau, Yuen-Sum, Soares-da-Silva, Patricio, Creswell, Karen, Guillemette, Gaetan, Sibley, David R., Eisner, Gilbert, Felder, Robin A., and Jose, Pedro A.
- Subjects
Angiotensin -- Health aspects ,Angiotensin -- Research ,Dopamine -- Health aspects ,Dopamine -- Research ,Hypertension -- Risk factors ,Hypertension -- Care and treatment ,Hypertension -- Research - Abstract
Hypertension is a multigenic disorder in which abnormal counterregulation between dopamine and Ang II plays a role. Recent studies suggest that this counterregulation results, at least in part, from regulation of the expression of both the antihypertensive dopamine 5 receptor ([D.sub.5]R) and the prohypertensive Ang II type 1 receptor ([AT.sub.1]R). In this report, we investigated the in vivo and in vitro interaction between these GPCRs. Disruption of the gene encoding [D.sub.5]R in mice increased both blood pressure and [AT.sub.1]R protein expression, and the increase in blood pressure was reversed by [AT.sub.1]R blockade. Activation of [D.sub.5]R increased the degradation of glycosylated [AT.sub.1]R in proteasomes in HEK cells and human renal proximal tubule cells heterologously and endogenously expressing human [AT.sub.1]R and [D.sub.5]R. Confocal microscopy, Forster/fluorescence resonance energy transfer microscopy, and fluorescence lifetime imaging microscopy revealed that activation of [D.sub.5]R initiated ubiquitination of the glycosylated [AT.sub.1]R at the plasma membrane. The regulated degradation of [AT.sub.1]R via a ubiquitin/proteasome pathway by activation of [D.sub.5]R provides what we believe to be a novel mechanism whereby blood pressure can be regulated by the interaction of 2 counterregulatory GPCRs. Our results therefore suggest that treatments for hypertension might be optimized by designing compounds that can target the [AT.sub.1]R and the [D.sub.5]R., Introduction Hypertension is associated with sodium retention caused by decreased renal sodium excretion, which is tightly regulated by both natriuretic and antinatriuretic hormones. Dopamine and Ang II are among those [...]
- Published
- 2008
6. Poly I:C induces development of diabetes mellitus in BB rat
- Author
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Sobel, Douglas O., Newsome, Joseph, Ewel, Cynthia H., Bellanti, Joseph A., Abbassi, Val, Creswell, Karen, and Blair, Owen
- Subjects
Interferon inducers -- Physiological aspects -- Usage ,Diabetes -- Development and progression ,Rats as laboratory animals -- Usage -- Physiological aspects ,Health ,Physiological aspects ,Usage ,Development and progression - Abstract
Polyinosinic polycytidilic acid (poly I:C), an inducer of α -interferon, accelerates the development of diabetes in diabetes-prone (DP) BioBreeding (BB) rats. this study investigates the effect of administering poly I:C to a diabetes-resistant (DR) strain of BB rats. We compared the incidence of diabetes, the degree of insulitis, the number of NK cells, helper-inducer cells, cytotoxic-suppresor cells, [la.sup.+] T cells, [RT6.1.sup.+] T cells, and NK cell bioactivity in Dr rats treated with saline and with a 5 μ /body wt (poly-5) dose and a 10 μ /g body wt (poly-10) dose of poly I:C. The incidence of diabetes was also compared with that of DP rats receiving poly-5. We found that both doses of poly I:C significantly induce the development of diabetes in the DR BB rat. However, treatment of DR rats with the higher dose induces a greater rate of development of diabetes and earlier onset of diabetes than the lower poly-5 dose. The rate of diabetes development and the mean age of onset were similar in poly-10-treated DR and poly-5-treated DP rats. A significant degree of insulitis occurred in all the poly I:C-treated DR rats, even those not developing diabetes. Peripheral blood NK cell number was greater in poly I:C than in saline-treated rats, after 2 wk of treatment and when killed. The percentage of [OX19.sup.+] peripheral blood mononuclear cells expressing RT6.1 allotype or la antigen were similar in poly I:C-and saline-treated rats. We conclude that poly-10 administration alone can induce diabetes in 100% of DR rats, and although treatment with poly-5 is less effective, it causes significant insulitis in all treated rats. The similar mean time of onset and rate of development of diabetes in poly-10-treated DR rats and poly-5-treated DP rats is consistent with a similar mechanism of poly I:C action in the DR and DP BB rats. Although the specific mechanism is not defined, NK cell numbers are elevated with poly 1:C treatment. Alterations in [RT6.1.sup.+] and [la.sup.+] T cells do not appear to play a role. Diabetes 41:515-20, 1992, The BB/W or rat has been used as an animal model to study the pathogenesis of diabetes mellitus. As in the human, this rat has insulin deficiency and exhibits many [...]
- Published
- 1992
7. A phase II multi-cohort single-arm study of tiragolumab with atezolizumab plus bevacizumab in previously treated advanced non-squamous non–small-cell lung cancer.
- Author
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Reuss, Joshua E., Wonser, Dann, Smith, Kellie Nicole, Ahn, Jaeil, Byers, Stephen, Creswell, Karen, Kim, Chul, Thompson, Jillian, Crawford, Jenny, Cohen, Emil, Zeck, Jay, Gutierrez, Martin, and Liu, Stephen V.
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- 2023
- Full Text
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8. Monoclonal Antibodies for the Detection of a Specific Cyclic DNA Adduct Derived from ω‑6 Polyunsaturated Fatty Acids.
- Author
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Dyba, Marcin, da Silva, Brandon, Coia, Heidi, Hou, Yanqi, Noguchi, Sumire, Pan, Jishen, Berry, Deborah, Creswell, Karen, Krzeminski, Jacek, Desai, Dhimant, Amin, Shantu, Yang, David, and Chung, Fung-Lung
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- 2018
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9. Detection of DNA adduct γ-OHPdG in circulating tumor cells (CTCs) and its use as a prognostic biomarker in patients with hepatocellular carcinoma (HCC).
- Author
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He, Aiwu Ruth, Chung, Fung-Lung, Aggarwal, Monika, Zhu, Zizhao, Gould, Sophie, Zhang, Kevin, Kuo, Mark, Johnson, Peter, Beheshtian, Samira, Kuhlman, Laura, Zhao, Zijun, Fang, Hongbin, Kallakury, Bhaskar, Creswell, Karen, and Kroemer, Alexander
- Published
- 2023
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10. Detection of Acrolein-DerivedCyclic DNA Adducts inHuman Cells by Monoclonal Antibodies.
- Author
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Pan, Jishen, Awoyemi, Bisola, Xuan, Zhuoli, Vohra, Priya, Wang, Hsiang-Tsui, Dyba, Marcin, Greenspan, Emily, Fu, Ying, Creswell, Karen, Zhang, Lihua, Berry, Deborah, Tang, Moon-Shong, and Chung, Fung-Lung
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- 2012
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11. Characterization of anti-islet cytotoxic human T-cell clones from patients with type 1 diabetes mellitus.
- Author
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Sobel, Douglas O. and Creswell, Karen
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CLONE cells , *T-cell receptor genes , *ANTIGENS , *DIABETES , *HEAT shock proteins , *CELL-mediated cytotoxicity , *LYMPHOCYTES - Abstract
To identify important anti-islet T-cells and their target antigen(s), we have isolated and characterized seventeen human T-cell clones which are reactive to an extract of rat insulinoma (RIN) cells from three children with new onset type 1 diabetes mellitus (T1D). Of these 17 clones, 15 were found tissue specific. Six of eight tested tissue specific clones did not recognize known islet antigens such as GAD, 52 kDa islet protein, insulin, ICA512, and heat shock protein 60 (hsp60), suggesting that these clones recognize an autoantigen not previously identified. All tested clones were phenotypically CD4 and functionally Th0 or Th0/Th1 cells. One RIN extract reactive clone (2E9) recognized hsp60 and was CD4 and TCR α/β positive. This clone also proliferated in response to human and rat islets suggesting that the antigen is conserved between species. This clone and 75% of all the tested RIN reactive clones exhibited anti-islet cytotoxicity by lysing target cells coated with RIN extract. HLA DR determinants may play a role in this cytotoxic activity since preincubation with HLA DR antibody decreased the anti-islet cytoxicity of the two tested clones. In conclusion, we have isolated RIN reactive CD4+T-cell clones from diabetic subjects, six of which appears tissue specific and non-reactive to putative important islet antigens, and in turn may be recognizing yet undiscovered islet antigens. The high frequency anti-islet cytotoxic properties of the islet reactive clones provides evidence for a role of CD4+ cytotoxic T-lymphocytes in the diabetic process. Further, the isolation of hsp60 reactive clone with anti-islet cytotoxic properties suggests that cell mediated immunity against hsp60 may be important in the pathogenesis of diabetes. [ABSTRACT FROM AUTHOR]
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- 2006
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12. Microvariation creates significant functional differences in the DR3 Molecules
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Posch, Phillip E., Araujo, Hugo A., Creswell, Karen, Praud, Chantai, Johnson, Armead H., and Hurley, Carolyn Katovich
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- 1995
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13. Environmental Degradation of the Insect Growth Regulator Isopropyl (2E,4E)-11-Methoxy-3,7,11-trimethyl-2,4-dodecadienoate (Methoprene). IV. Soil Metabolism
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Quistad, Gary B., Creswell, Karen M., Staiger, Luana E., and Schooley, David A.
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- 1975
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14. Nucleotide excision repair deficiency increases levels of acrolein-derived cyclic DNA adduct and sensitizes cells to apoptosis induced by docosahexaenoic acid and acrolein.
- Author
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Pan, Jishen, Sinclair, Elizabeth, Xuan, Zhuoli, Dyba, Marcin, Fu, Ying, Sen, Supti, Berry, Deborah, Creswell, Karen, Hu, Jiaxi, Roy, Rabindra, and Chung, Fung-Lung
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NUCLEOTIDES , *ACROLEIN , *APOPTOSIS , *UNSATURATED fatty acids , *DOCOSAHEXAENOIC acid , *BIOMARKERS , *THERAPEUTICS - Abstract
The acrolein derived cyclic 1,N 2 -propanodeoxyguanosine adduct (Acr-dG), formed primarily from ω-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA) under oxidative conditions, while proven to be mutagenic, is potentially involved in DHA-induced apoptosis. The latter may contribute to the chemopreventive effects of DHA. Previous studies have shown that the levels of Acr-dG are correlated with apoptosis induction in HT29 cells treated with DHA. Because Acr-dG is shown to be repaired by the nucleotide excision repair (NER) pathway, to further investigate the role of Acr-dG in apoptosis, in this study, NER-deficient XPA and its isogenic NER-proficient XAN1 cells were treated with DHA. The Acr-dG levels and apoptosis were sharply increased in XPA cells, but not in XAN1 cells when treated with 125 μM of DHA. Because DHA can induce formation of various DNA damage, to specifically investigate the role of Acr-dG in apoptosis induction, we treated XPA knockdown HCT116 + ch3 cells with acrolein. The levels of both Acr-dG and apoptosis induction increased significantly in the XPA knockdown cells. These results clearly demonstrate that NER deficiency induces higher levels of Acr-dG in cells treated with DHA or acrolein and sensitizes cells to undergo apoptosis in a correlative manner. Collectively, these results support that Acr-dG, a ubiquitously formed mutagenic oxidative DNA adduct, plays a role in DHA-induced apoptosis and suggest that it could serve as a biomarker for the cancer preventive effects of DHA. [ABSTRACT FROM AUTHOR]
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- 2016
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15. Ly6E/K Signaling to TGFβPromotes Breast Cancer Progression, Immune Escape, and Drug Resistance.
- Author
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AlHossiny, Midrar, Linlin Luo, Frazier, William R., Steiner, Noriko, Yuriy Gusev, Kallakury, Bhaskar, Glasgow, Eric, Creswell, Karen, Madhavan, Subha, Kumar, Rakesh, and Upadhyay, Geeta
- Subjects
- *
TRANSFORMING growth factors-beta , *BREAST cancer patients , *DISEASE progression , *HEALTH outcome assessment , *GENE expression - Abstract
Stem cell antigen Sca-1 is implicated in murine cancer stem cell biology and breast cancer models, but the role of its human homologs Ly6K and Ly6E in breast cancer are not established. Here we report increased expression of Ly6K/E in human breast cancer specimens correlates with poor overall survival, with an additional specific role for Ly6E in poor therapeutic outcomes. Increased expression of Ly6K/E also correlated with increased expression of the immune checkpoint molecules PDL1 and CTLA4, increased tumor-infiltrating T regulatory cells, and decreased natural killer (NK) cell activation. Mechanistically, Ly6K/E was required for TGFβ signaling and proliferation in breast cancer cells, where they contributed to phosphorylation of Smad1/5 and Smad2/3. Furthermore, Ly6K/E promoted cytokine- induced PDL1 expression and activation and binding of NK cells to cancer cells. Finally, we found that Ly6K/E promoted drug resistance and facilitated immune escape in this setting. Overall, our results establish a pivotal role for a Ly6K/E signaling axis involving TGFβ in breast cancer pathophysiology and drug response, and highlight this signaling axis as a compelling realm for therapeutic invention. [ABSTRACT FROM AUTHOR]
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- 2016
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16. Inhibition of c-Src blocks oestrogen-induced apoptosis and restores oestrogen-stimulated growth in long-term oestrogen-deprived breast cancer cells.
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Fan, Ping, Agboke, Fadeke A., McDaniel, Russell E., Sweeney, Elizabeth E., Zou, Xiaojun, Creswell, Karen, and Jordan, V. Craig
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RNA analysis , *BREAST tumors , *FLOW cytometry , *POLYMERASE chain reaction , *OXIDATIVE stress , *DESCRIPTIVE statistics - Abstract
Abstract: Purpose: Our publications demonstrate that physiological concentrations of oestrogen (E2) induce endoplasmic reticulum and oxidative stress which finally result in apoptosis in E2-deprived breast cancer cells, MCF-7:5C. c-Src is involved in the process of E2-induced stress. To mimic the clinical administration of c-Src inhibitors, we treated cells with either E2, a c-Src inhibitor PP2, or the combination for 8weeks to further explore the apoptotic potential of the c-Src inhibitor and E2 on MCF-7:5C cells. Methods: Protein levels of receptors and signalling pathways were examined by immunoblotting. Expression of mRNA was detected through real-time polymerase chain reaction (PCR). Cell cycles were analysed by flow cytometry. Results: Long-term treatment with PP2 alone or E2 alone decreased cell growth. In contrast, a combination of PP2 and E2 blocked apoptosis and the resulting cell line (MCF-7:PF) was unique, as they grew vigorously in culture with physiological levels of E2, which could be blocked by the pure antioestrogen ICI182,780. One major change was that PP2 collaborated with E2 to increase the level of insulin-like growth factor-1 receptor beta (IGF-1Rβ). Blockade of IGF-1Rβ completely abolished E2-stimulated growth in MCF-7:PF cells. Furthermore, combination treatment up-regulated transcription factors, Twist1 and Snail, and repressed E-cadherin expression which made MCF-7:PF cells display a characteristic phenotype of epithelial–mesenchymal transition (EMT). Conclusions: These data illustrate the role of the c-Src inhibitor to block E2-induced apoptosis and enhance E2-stimulated growth. Caution must be exercised when considering c-Src inhibitors in clinical trials following the development of acquired resistance to aromatase inhibitors, especially in the presence of the patient’s own oestrogen. [Copyright &y& Elsevier]
- Published
- 2014
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17. c-Src Modulates Estrogen-Induced Stress and Apoptosis in Estrogen-Deprived Breast Cancer Cells.
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Ping Fan, Griffith, Obi L., Agboke, Fadeke A., Anur, Pavana, Xiaojun Zou, McDaniel, Russell E., Creswell, Karen, Sung Hoon Kim, Katzenellenbogen, John A., Gray, Joe W., and Jordan, V. Craig
- Subjects
- *
ESTROGEN , *BREAST cancer , *APOPTOSIS , *ESTROGEN receptors , *HEME oxygenase - Abstract
The emergence of anti-estrogen resistance in breast cancer is an important clinical phenomenon affecting long-term survival in this disease. Identifying factors that convey cell survival in this setting may guide improvements in treatment. Estrogen (E2) can induce apoptosis in breast cancer cells that have been selected for survival after E2 deprivation for long periods (MCF-7:5C cells), but the mechanisms underlying E2-induced stress in this setting have not been elucidated. Here, we report that the c-Src kinase functions as a key adapter protein for the estrogen receptor (ER, ESR1) in its activation of stress responses induced by E2 in MCF-7:5C cells. E2 elevated phosphorylation of c-Src, which was blocked by 4-hydroxytamoxifen (4-OHT), suggesting that E2 activated c-Src through the ER. We found that E2 activated the sensors of the unfolded protein response (UPR), IRE1a (ERN1) and PERK kinase (EIF2AK3), the latter of which phosphorylates eukaryotic translation initiation factor-2a (eIF2a). E2 also dramatically increased reactive oxygen species production and upregulated expression of heme oxygenase HO-1 (HMOX1), an indicator of oxidative stress, along with the central energy sensor kinase AMPK (PRKAA2). Pharmacologic or RNA interference-mediated inhibition of c-Src abolished the phosphorylation of eIF2a and AMPK, blocked E2-induced ROS production, and inhibited E2-induced apoptosis. Together, our results establish that c-Src kinase mediates stresses generated by E2 in long-term E2-deprived cells that trigger apoptosis. This work offers a mechanistic rationale for a new approach in the treatment of endocrine-resistant breast cancer. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
18. Dopamine 5 receptor mediates Ang II type 1 receptor degradation via a ubiquitin-proteasome pathway in mice and human cells.
- Author
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Hewang Li, Armando, Ines, Peiying Yu, Escano, Crisanto, Mueller, Susette C., Asico, Laureano, Pascua, Annabelle, Quansheng Lu, Xiaoyan Wang, Villar, Van Anthony M., Jones, John E., Zheng Wang, Periasamy, Ammasi, Yuen-Sum Lau, Soares-da-Silva, Patricio, Creswell, Karen, Guillemette, Gaétan, Sibley, David R., Eisner, Gilbert, and Felder, Robin A.
- Subjects
- *
DOPAMINE , *HYPERTENSION , *ENERGY transfer , *CELL membranes , *UBIQUITIN , *PROTEIN metabolism , *ANIMAL experimentation , *BIOLOGICAL models , *BLOOD pressure , *CELL lines , *CELL receptors , *GENES , *GLYCOSYLATION , *KIDNEY tubules , *MICE , *PROTEOLYTIC enzymes , *RESEARCH funding , *CELL physiology - Abstract
Hypertension is a multigenic disorder in which abnormal counterregulation between dopamine and Ang II plays a role. Recent studies suggest that this counterregulation results, at least in part, from regulation of the expression of both the antihypertensive dopamine 5 receptor (D5R) and the prohypertensive Ang II type 1 receptor (AT1R). In this report, we investigated the in vivo and in vitro interaction between these GPCRs. Disruption of the gene encoding D5R in mice increased both blood pressure and AT1R protein expression, and the increase in blood pressure was reversed by AT1R blockade. Activation of D5R increased the degradation of glycosylated AT1R in proteasomes in HEK cells and human renal proximal tubule cells heterologously and endogenously expressing human AT1R and D5R. Confocal microscopy, Förster/fluorescence resonance energy transfer microscopy, and fluorescence lifetime imaging microscopy revealed that activation of D5R initiated ubiquitination of the glycosylated AT1R at the plasma membrane. The regulated degradation of AT1R via a ubiquitin/proteasome pathway by activation of D5R provides what we believe to be a novel mechanism whereby blood pressure can be regulated by the interaction of 2 counterregulatory GPCRs. Our results therefore suggest that treatments for hypertension might be optimized by designing compounds that can target the AT1R and the D5R. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
19. Discovery of a stem-like multipotent cell fate.
- Author
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Paffhausen ES, Alowais Y, Chao CW, Callihan EC, Creswell K, and Bracht JR
- Abstract
Adipose derived stem cells (ASCs) can be obtained from lipoaspirates and induced in vitro to differentiate into bone, cartilage, and fat. Using this powerful model system we show that after in vitro adipose differentiation a population of cells retain stem-like qualities including multipotency. They are lipid (-), retain the ability to propagate, express two known stem cell markers, and maintain the capacity for trilineage differentiation into chondrocytes, adipocytes, and osteoblasts. However, these cells are not traditional stem cells because gene expression analysis showed an overall expression profile similar to that of adipocytes. In addition to broadening our understanding of cellular multipotency, our work may be particularly relevant to obesity-associated metabolic disorders. The adipose expandability hypothesis proposes that inability to differentiate new adipocytes is a primary cause of metabolic syndrome in obesity, including diabetes and cardiovascular disease. Here we have defined a differentiation-resistant stem-like multipotent cell population that may be involved in regulation of adipose expandability in vivo and may therefore play key roles in the comorbidities of obesity., Competing Interests: None.
- Published
- 2018
20. c-Src modulates estrogen-induced stress and apoptosis in estrogen-deprived breast cancer cells.
- Author
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Fan P, Griffith OL, Agboke FA, Anur P, Zou X, McDaniel RE, Creswell K, Kim SH, Katzenellenbogen JA, Gray JW, and Jordan VC
- Subjects
- AMP-Activated Protein Kinases metabolism, Breast Neoplasms enzymology, Breast Neoplasms pathology, CSK Tyrosine-Protein Kinase, Cell Line, Tumor, Endoplasmic Reticulum metabolism, Endoribonucleases metabolism, Eukaryotic Initiation Factor-2 metabolism, Female, Heme Oxygenase-1 metabolism, Humans, MCF-7 Cells, Phosphorylation, Protein Serine-Threonine Kinases metabolism, Reactive Oxygen Species metabolism, Receptors, Estrogen metabolism, Unfolded Protein Response physiology, eIF-2 Kinase metabolism, Apoptosis physiology, Breast Neoplasms metabolism, Estrogens deficiency, Estrogens metabolism, Oxidative Stress physiology, src-Family Kinases metabolism
- Abstract
The emergence of anti-estrogen resistance in breast cancer is an important clinical phenomenon affecting long-term survival in this disease. Identifying factors that convey cell survival in this setting may guide improvements in treatment. Estrogen (E2) can induce apoptosis in breast cancer cells that have been selected for survival after E2 deprivation for long periods (MCF-7:5C cells), but the mechanisms underlying E2-induced stress in this setting have not been elucidated. Here, we report that the c-Src kinase functions as a key adapter protein for the estrogen receptor (ER, ESR1) in its activation of stress responses induced by E2 in MCF-7:5C cells. E2 elevated phosphorylation of c-Src, which was blocked by 4-hydroxytamoxifen (4-OHT), suggesting that E2 activated c-Src through the ER. We found that E2 activated the sensors of the unfolded protein response (UPR), IRE1α (ERN1) and PERK kinase (EIF2AK3), the latter of which phosphorylates eukaryotic translation initiation factor-2α (eIF2α). E2 also dramatically increased reactive oxygen species production and upregulated expression of heme oxygenase HO-1 (HMOX1), an indicator of oxidative stress, along with the central energy sensor kinase AMPK (PRKAA2). Pharmacologic or RNA interference-mediated inhibition of c-Src abolished the phosphorylation of eIF2α and AMPK, blocked E2-induced ROS production, and inhibited E2-induced apoptosis. Together, our results establish that c-Src kinase mediates stresses generated by E2 in long-term E2-deprived cells that trigger apoptosis. This work offers a mechanistic rationale for a new approach in the treatment of endocrine-resistant breast cancer., (©2013 AACR.)
- Published
- 2013
- Full Text
- View/download PDF
21. Detection of acrolein-derived cyclic DNA adducts in human cells by monoclonal antibodies.
- Author
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Pan J, Awoyemi B, Xuan Z, Vohra P, Wang HT, Dyba M, Greenspan E, Fu Y, Creswell K, Zhang L, Berry D, Tang MS, and Chung FL
- Subjects
- Animals, Biomarkers, Cells, Cultured, Chromatography, Liquid, Enzyme-Linked Immunosorbent Assay, HT29 Cells, Humans, Keratinocytes, Mice, Mice, Inbred BALB C, Mouth cytology, Tandem Mass Spectrometry, Acrolein immunology, Air Pollutants immunology, Antibodies, Monoclonal immunology, DNA Adducts immunology
- Abstract
Acrolein (Acr) is a ubiquitous environmental pollutant found in cigarette smoke and automobile exhaust. It can also be produced endogenously by oxidation of polyunsaturated fatty acids. The Acr-derived 1,N(2)-propanodeoxyguanosine (Acr-dG) adducts in DNA are mutagenic lesions that are potentially involved in human cancers. In this study, monoclonal antibodies were raised against Acr-dG adducts and characterized using ELISA. They showed strong reactivity and specificity toward Acr-dG, weaker reactivity toward crotonaldehyde- and trans-4-hydroxy-2-nonenal-derived 1,N(2)-propanodeoxyguanosines, and weak or no reactivity toward 1,N(6)-ethenodeoxyadenosine and 8-oxo-deoxyguanosine. Using these antibodies, we developed assays to detect Acr-dG in vivo: first, a simple and quick FACS-based assay for detecting these adducts directly in cells; second, a highly sensitive direct ELISA assay for measuring Acr-dG in cells and tissues using only 1 μg of DNA without DNA digestion and sample enrichment; and third, a competitive ELISA for better quantitative measurement of Acr-dG levels in DNA samples. The assays were validated using Acr-treated HT29 cell DNA samples or calf thymus DNA, and the results were confirmed by LC-MS/MS-MRM. An immunohistochemical assay was also developed to detect and visualize Acr-dG in HT29 cells as well as in human oral cells. These antibody-based methods provide useful tools for the studies of Acr-dG as a cancer biomarker and of the molecular mechanisms by which cells respond to Acr-dG as a ubiquitous DNA lesion.
- Published
- 2012
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22. Tachyplesin activates the classic complement pathway to kill tumor cells.
- Author
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Chen J, Xu XM, Underhill CB, Yang S, Wang L, Chen Y, Hong S, Creswell K, and Zhang L
- Subjects
- Amino Acid Sequence, Antimicrobial Cationic Peptides immunology, Antimicrobial Cationic Peptides metabolism, Cell Line, Tumor, Complement C1q metabolism, Complement C3b immunology, Complement C3b metabolism, Complement C4b immunology, Complement C4b metabolism, DNA-Binding Proteins immunology, DNA-Binding Proteins metabolism, Flow Cytometry, Humans, Hyaluronic Acid immunology, Hyaluronic Acid metabolism, Molecular Sequence Data, Peptide Library, Peptides, Cyclic immunology, Peptides, Cyclic metabolism, Urinary Bladder Neoplasms drug therapy, Urinary Bladder Neoplasms immunology, Urinary Bladder Neoplasms metabolism, Antimicrobial Cationic Peptides pharmacology, Complement Pathway, Classical drug effects, DNA-Binding Proteins pharmacology, Peptides, Cyclic pharmacology
- Abstract
Tachyplesin is a small, cationic peptide that possesses antitumor properties. However, little is known about its action mechanism. We used phage display to identify a protein that interacted with tachyplesin and isolated a sequence corresponding to the collagen-like domain of C1q, a key component in the complement pathway. Their interaction was subsequently confirmed by both ELISA and affinity precipitation. Tachyplesin seemed to activate the classic complement cascade because it triggered several downstream events, including the cleavage and deposition of C4 and C3 and the formation of C5b-9. When TSU tumor cells were treated with tachyplesin in the presence of serum, activated C4b and C3b could be detected on tumor cells by flow cytometry, Western blotting, and confocal microscopy. However, this effect was blocked when the tumor cells were treated with hyaluronidase or a large excess of hyaluronan, indicating that hyaluronan or related glycosaminoglycans were involved in this process. Treatment of cells with tachyplesin and serum increased in membrane permeability as indicated by the ability of FITC-dextran to enter the cytoplasm. Finally, the combination of tachyplesin and human serum markedly inhibited the proliferation and caused death of TSU cells, and these effects were attenuated if the serum was heat-inactivated or if hyaluronidase was added. Taken together, these observations suggest that tachyplesin binds to both hyaluronan on the cell surface and C1q in the serum and activates the classic complement cascade, which damages the integrity of the membranes of the tumor cells resulting in their death.
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- 2005
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- View/download PDF
23. A peptide with three hyaluronan binding motifs inhibits tumor growth and induces apoptosis.
- Author
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Xu XM, Chen Y, Chen J, Yang S, Gao F, Underhill CB, Creswell K, and Zhang L
- Subjects
- Amino Acid Motifs, Amino Acid Sequence, Animals, Antineoplastic Agents chemical synthesis, Antineoplastic Agents metabolism, Binding Sites, Cell Division drug effects, Cell Line, Tumor, Cell Membrane drug effects, Cell Membrane metabolism, Cell Membrane Permeability drug effects, Humans, Hyaluronan Receptors genetics, Hyaluronan Receptors metabolism, Hyaluronic Acid metabolism, Melanoma genetics, Melanoma pathology, Melanoma, Experimental drug therapy, Melanoma, Experimental pathology, Mice, Mice, Nude, Molecular Sequence Data, Peptide Fragments chemical synthesis, Peptide Fragments metabolism, Structure-Activity Relationship, Transfection, Xenograft Model Antitumor Assays, Antineoplastic Agents pharmacology, Apoptosis drug effects, Hyaluronan Receptors pharmacology, Melanoma drug therapy, Peptide Fragments pharmacology
- Abstract
A number of hyaluronan (HA) binding proteins such as soluble CD44, receptor for hyaluronan-mediated motility (RHAMM), and metastatin inhibit tumor growth and metastasis. To determine whether the HA binding motif is the element responsible for the antitumor effect of this family of proteins, we examined the biological activity of a 42-amino acid peptide (designated as BH-P) that contains three HA binding motifs [B(X(7))B] from human brain HA binding protein. In initial experiments with cultured cells, we found that synthetic BH-P inhibited the proliferation and colony formation of tumor cells. It also blocked the growth of tumors on the chorioallantoic membranes of 10-day chicken embryos. In addition, MDA-435 melanoma cells that had been transfected with an expression vector for BH-P grew at a slower rate in nude mice than the vector-alone transfectants. Final studies revealed that the BH-P could activate caspase-8, caspase-3, and poly(ADP-ribose) polymerase and trigger the apoptosis of tumor cells. Taken together, these results suggest that the HA binding motif that is present in HA binding proteins may be responsible for the antitumor effect exerted by the members of this family.
- Published
- 2003
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