1
|
Baxter RC, Lin MZ, Marzec KA, Martin JL. Abstract P5-07-05: Insulin-like growth factor binding protein-3 is a key component of the breast cancer cell response to DNA-damaging therapy. Cancer Res 2012. [DOI: 10.1158/0008-5472.sabcs12-p5-07-05] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction. Breast cancer cells frequently develop resistance to DNA-damaging therapies, such as radiation and the cytotoxic drugs doxorubicin and etoposide, and activation of the epidermal growth factor receptor (EGFR) may play an important role in this process. However many estrogen receptor (ER)-negative breast tumors respond poorly to DNA-damaging drugs even when combined with an EGFR inhibitor. EGFR can modulate the repair of DNA double strand breaks (DSB) by non-homologous end-joining (NHEJ), by forming protein complexes that include the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs). In previous studies we have shown that the growth-regulatory protein, insulin-like growth factor binding protein-3 (IGFBP-3), can translocate to the nucleus, is a substrate for DNA-PKcs, and can transactivate EGFR. The aim of this study was to delineate the role of IGFBP-3 in the response of breast cancer cells to DSB-inducing chemotherapeutic agents.
Results. In the triple-negative breast cancer cell lines MDA-MB-468 and Hs578T, which express IGFBP-3 highly, nuclear localization of EGFR and IGFBP-3, and of their complex as measured by coimmunoprecipitation (coIP), was enhanced by exposure to etoposide or doxorubicin, peaking 2 h after etoposide treatment. This effect was blocked by the EGFR kinase inhibitor gefitinib. Concomitantly, the co-location of EGFR-IGFBP-3 complexes with lipid rafts, visualized by proximity ligation assay (PLA) and confocal microscopy, decreased in response to drug treatment, consistent with the loss of this complex from the plasma membrane. Similar to the nuclear DNA-PKcs-EGFR complex, the nuclear DNA-PKcs-IGFBP-3 complex (seen by both coIP and PLA) was greatest 4 h after treatment. DNA-PKcs activation at serine-2056, required for the repair of DNA DSB and stimulated by etoposide treatment, was decreased by IGFBP-3 downregulation using two separate siRNAs, and this treatment also attenuated the enhanced DNA-PKcs-EGFR complexes seen in response to etoposide. Collectively these data suggest that IGFBP-3 has an obligatory role in the DNA repair response to DNA-damaging therapy through its interactions with EGFR and DNA-PKcs.
Conclusion. IGFBP-3 co-translocation to the nucleus of breast cancer cells and its complex formation with DNA-PKcs and EGFR in response to DNA damage demonstrate its previously unrecognized involvement in the regulation of DNA DSB repair by NHEJ. These novel findings suggests the possibility of a therapeutic approach for sensitizing ER-negative breast cancers to chemo- or radiotherapy by targeting the DNA repair function of IGFBP-3. Supported by the Australian Research Council.
Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-07-05.
Collapse
Affiliation(s)
- RC Baxter
- University of Sydney, Sydney, NSW, Australia
| | - MZ Lin
- University of Sydney, Sydney, NSW, Australia
| | - KA Marzec
- University of Sydney, Sydney, NSW, Australia
| | - JL Martin
- University of Sydney, Sydney, NSW, Australia
| |
Collapse
|
2
|
Menchine M, Solomon T, Marzec K, Rifenbark N, Nayyar M, Patel S, Arora S. 457: Prevalence and Severity of Depression In Emergency Department Patients With Diabetes: What Is the Association With Glycemic Control? Ann Emerg Med 2010. [DOI: 10.1016/j.annemergmed.2010.06.500] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
3
|
Arora S, Marzec K, Solomon T, Gates C, Vasquez V, Bach D, Damodar D, Menchine M. 166: Baseline Hemoglobin A1C and Associated Patient Characteristics of Patients With Diabetes Seen In an Urban Emergency Department. Ann Emerg Med 2010. [DOI: 10.1016/j.annemergmed.2010.06.213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
4
|
Vogl TJ, Bartjes M, Marzec K. Contrast-enhanced lymphography. CT or MR imaging? Acta Radiol Suppl 1997; 412:47-50. [PMID: 9240080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Lymphography is the radiological visualization of the lymph vessels and lymph nodes with contrast material. History and different modes of visualization are compared.
Collapse
Affiliation(s)
- T J Vogl
- Department of Radiology, Virchow Hospital, University of Berlin, Germany
| | | | | |
Collapse
|
5
|
Marzec K, Lesiak T. New Possibilities of Application of Furfural for the Synthesis of Self-extinguishing Polyurethane Intermediates. HETEROCYCLES 1978. [DOI: 10.3987/r-1978-10-1485-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
6
|
Lesiak T, Hetper J, Pielichowski J, Prewysz-Kwinto A, Marzec K. Application of gas chromatography to the analysis of thermal decomposition products of some sulphur containing polyurethanes. POLYMER 1976. [DOI: 10.1016/0032-3861(76)90018-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|