Eugene Izumchenko

Publications of Eugene Izumchenko

• Enhanced genetic instability and dasatinib sensitivity in mammary tumor cells lacking NEDD9.

  Authors: Mahendra K Singh, Eugene Izumchenko, Andres J Klein-Szanto, Brian L Egleston, Marina Wolfson, Erica A Golemis

  Cancer research. 10/2010; 70(21):8907-16.

  Elevated expression of the NEDD9/HEF1/Cas-L scaffolding protein promotes tumor cell invasion and metastasis in multiple cancer cell types. Conversely, generation of mammary tumors in the mouseElevated expression of the NEDD9/HEF1/Cas-L scaffolding protein promotes tumor cell invasion and metastasis in multiple cancer cell types. Conversely, generation of mammary tumors in the mouse mammary tumor virus (MMTV)-polyoma virus middle T (PyVT) genetic model is delayed by a Nedd9(-/-) genotype. These activities arise from the role of NEDD9 in assembling complexes and supporting activity of cancer signaling proteins, including FAK, Src, Shc, and AKT, and would support evaluation of NEDD9 expression as an unambiguous biomarker for tumor aggressiveness. However, we here show that despite the initial delay in tumor growth, cells derived from MMTV-PyVT;Nedd9(-/-) tumors are characteristically hyperaggressive versus MMTV-PyVT;Nedd9(+/+) cells in anchorage-independent growth, in growth on three-dimensional matrix produced by tumor-associated fibroblasts, and in formation of tumors after mammary orthotopic reinjection and of lung metastases after tail vein injection. This reversal suggests the specific selection of MMTV-PyVT;Nedd9(-/-) cells for growth in an in vivo microenvironment. Indeed, MMTV-PyVT;Nedd9(-/-) cells have increased cell cycle, centrosomal, and mitotic defects, phenotypes compatible with the increased selection of these cells for aggressive growth. Intriguingly, in spite of their aggressive phenotype, MMTV-PyVT;Nedd9(-/-) cells persistently have low levels of Src activation and are hypersensitive to the Src kinase inhibitor dasatinib. These studies identify NEDD9 as a complex modulator of different aspects of mammary tumor growth.

  Download

• NEDD9 Promotes Oncogenic Signaling in Mammary Tumor Development.

  Authors: Eugene Izumchenko, Mahendra K Singh, Olga V Plotnikova, Nadezhda Tikhmyanova, Joy L Little, Ilya G Serebriiskii, Sachiko Seo, Mineo Kurokawa, Brian L Egleston, Andres Klein-Szanto, Elena N Pugacheva, Richard R Hardy, Marina Wolfson, Denise C Connolly, Erica A Golemis

  Cancer research. 10/2009;

  In the past 3 years, altered expression of the HEF1/CAS-L/NEDD9 scaffolding protein has emerged as contributing to cancer metastasis in multiple cancer types. However, whereas some studies haveIn the past 3 years, altered expression of the HEF1/CAS-L/NEDD9 scaffolding protein has emerged as contributing to cancer metastasis in multiple cancer types. However, whereas some studies have identified elevated NEDD9 expression as prometastatic, other work has suggested a negative role in tumor progression. We here show that the Nedd9-null genetic background significantly limits mammary tumor initiation in the MMTV-polyoma virus middle T genetic model. Action of NEDD9 is tumor cell intrinsic, with immune cell infiltration, stroma, and angiogenesis unaffected. The majority of the late-appearing mammary tumors of MMTV-polyoma virus middle T;Nedd9(-/-) mice are characterized by depressed activation of proteins including AKT, Src, FAK, and extracellular signal-regulated kinase, emphasizing an important role of NEDD9 as a scaffolding protein for these prooncogenic proteins. Analysis of cells derived from primary Nedd9(+/+) and Nedd9(-/-) tumors showed persistently reduced FAK activation, attachment, and migration, consistent with a role for NEDD9 activation of FAK in promoting tumor aggressiveness. This study provides the first in vivo evidence of a role for NEDD9 in breast cancer progression and suggests that NEDD9 expression may provide a biomarker for tumor aggressiveness. [Cancer Res 2009;69(18):7198-206].

• Cooperative antitumor effects of vitamin D3 derivatives and rosemary preparations in a mouse model of myeloid leukemia.

  Authors: Hagar Sharabani, Eugene Izumchenko, Qing Wang, Rita Kreinin, Michael Steiner, Zeev Barvish, Michael Kafka, Yoav Sharoni, Joseph Levy, Milan Uskokovic, George P Studzinski, Michael Danilenko

  International journal of cancer. Journal international du cancer. 07/2006; 118(12):3012-21.

  1alpha,25-dihydroxyvitamin D(3) (1,25D(3)) is a powerful differentiation agent, which has potential for treatment of myeloid leukemias and other types of cancer, but the calcemia produced by1alpha,25-dihydroxyvitamin D(3) (1,25D(3)) is a powerful differentiation agent, which has potential for treatment of myeloid leukemias and other types of cancer, but the calcemia produced by pharmacologically active doses precludes the use of this agent in the clinic. We have shown that carnosic acid, the major rosemary polyphenol, enhances the differentiating and antiproliferative effects of low concentrations of 1,25D(3) in human myeloid leukemia cell lines (HL60, U937). Here we translated these findings to in vivo conditions using a syngeneic mouse leukemia tumor model. To this end, we first demonstrated that as in HL60 cells, differentiation of WEHI-3B D(-) murine myelomonocytic leukemia cells induced by 1 nM 1,25D(3) or its low-calcemic analog, 1,25-dihydroxy-16-ene-5,6-trans-cholecalciferol (Ro25-4020), can be synergistically potentiated by carnosic acid (10 microM) or the carnosic acid-rich ethanolic extract of rosemary leaves. This effect was accompanied by cell cycle arrest in G0 + G1 phase and a marked inhibition of cell growth. In the in vivo studies, i.p. injections of 2 microg Ro25-4020 in Balb/c mice bearing WEHI-3B D(-) tumors produced a significant delay in tumor appearance and reduction in tumor size, without significant toxicity. Another analog, 1,25-dihydroxy-16,23Z-diene-20-epi-26,27-hexafluoro-19-nor-cholecalciferol (Ro26-3884) administered at the same dose was less effective than Ro25-4020 and profoundly toxic. Importantly, combined treatment with 1% dry rosemary extract (mixed with food) and 1 microg Ro25-4020 resulted in a strong cooperative antitumor effect, without inducing hypercalcemia. These results indicate for the first time that a plant polyphenolic preparation and a vitamin D derivative can cooperate not only in inducing leukemia cell differentiation in vitro, but also in the antileukemic activity in vivo. These data may suggest novel protocols for chemoprevention or differentiation therapy of myeloid leukemia.