This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. One of the major unsolved mysteries in tumor biology is the mechanism by which tumor cells in vivo exit from the cell cycle in a reversible fashion. An implicit assumption through decades of research is that limitations of nutrient supply, either by limited penetration into the cell mass or restricted blood flow to local regions, create a stressful microenvironment which induces cells to arrest their cell cycle transit. Due to well-known limitations of experimental tumors for such mechanistic studies, we are using the multicellular tumor spheroid model for the majority of this project. Spheroids are ideally suited for such studies, both because of their symmetrical arrangement of microenvironmental and cellular proliferation gradients, and because of our unique ability to experimentally exploit this symmetry. Specifically, we can isolate intact, viable cells from known locations within the spheroid microenvironment for detailed study of the molecular changes associated with cell cycle arrest. In order to provide a link between this in vitro system and the in vivo situation we will determine whether our proposed mechanism is operative in actual tumors. We are pursuing four Specific Aims: 1) to determine the molecular basis for cell cycle arrest in multicellular spheroids;2) to determine if the same molecular mechanisms are operative in tumors in vivo;3) to identify the microenvironmental signal(s) which induce cell cycle arrest in spheroids;and 4) to determine the interaction between radiation- and microenvironmentally-induced cell cycle arrest. Flow analysis is used both for routine DNA content analysis, and also for determining the uptake of bromodeoxyuridine by means of a dual-label DNA analysis technique. These cell cycle data are critical for comparison with our molecular analysis. We are also pursuing the measurement of cyclin and cyclin-dependent kinase expression by flow using fluorescently-tagged antibodies.
| Frumkin, Jesse P; Patra, Biranchi N; Sevold, Anthony et al. (2016) The interplay between chromosome stability and cell cycle control explored through gene-gene interaction and computational simulation. Nucleic Acids Res 44:8073-85 |
| Johnson, Leah M; Gao, Lu; Shields IV, C Wyatt et al. (2013) Elastomeric microparticles for acoustic mediated bioseparations. J Nanobiotechnology 11:22 |
| Micheva-Viteva, Sofiya N; Shou, Yulin; Nowak-Lovato, Kristy L et al. (2013) c-KIT signaling is targeted by pathogenic Yersinia to suppress the host immune response. BMC Microbiol 13:249 |
| Ai, Ye; Sanders, Claire K; Marrone, Babetta L (2013) Separation of Escherichia coli bacteria from peripheral blood mononuclear cells using standing surface acoustic waves. Anal Chem 85:9126-34 |
| Sanders, Claire K; Mourant, Judith R (2013) Advantages of full spectrum flow cytometry. J Biomed Opt 18:037004 |
| Cushing, Kevin W; Piyasena, Menake E; Carroll, Nick J et al. (2013) Elastomeric negative acoustic contrast particles for affinity capture assays. Anal Chem 85:2208-15 |
| Chen, Jun; Carter, Mark B; Edwards, Bruce S et al. (2012) High throughput flow cytometry based yeast two-hybrid array approach for large-scale analysis of protein-protein interactions. Cytometry A 81:90-8 |
| Piyasena, Menake E; Austin Suthanthiraraj, Pearlson P; Applegate Jr, Robert W et al. (2012) Multinode acoustic focusing for parallel flow cytometry. Anal Chem 84:1831-9 |
| Austin Suthanthiraraj, Pearlson P; Piyasena, Menake E; Woods, Travis A et al. (2012) One-dimensional acoustic standing waves in rectangular channels for flow cytometry. Methods 57:259-71 |
| Vuyisich, Momchilo; Sanders, Claire K; Graves, Steven W (2012) Binding and cell intoxication studies of anthrax lethal toxin. Mol Biol Rep 39:5897-903 |
Showing the most recent 10 out of 240 publications
