Ronald L Heimark
- Professor, Surgery
- Associate Professor, Pathology
- Associate Professor, Cellular and Molecular Medicine
- Professor, Ophthalmology
- Professor, Cancer Biology - GIDP
- Member of the Graduate Faculty
- Ph.D. Biochemistry
- University of California, Davis, California, United States
- Protein Composition of Ribosomal Binding Sites for Initiation Factors in Escherichia coliThesis Advisors: Robert R. Traut; John B. Hersey
- B.A. Biology/ Chemistry
- Western Washington University, Bellingham, Washington, United States
- University of Arizona, Department of Ophthalmology (2006 - Ongoing)
- University of Arizona, Department of Cellular and Medicine (2000 - Ongoing)
- University of Arizona, Department of Pathology (1999 - Ongoing)
- University of Arizona, Department of Surgery (1999 - 2005)
- Department of Surgery, University of Arizona (1993 - 1999)
- Dept. of Pathology; University of Washington (1990 - 1993)
- ICOS Corp. (1990 - 1993)
- Dept. Pathology; University of Washington (1986 - 1990)
- Irvine H. Page Research Award for Young Investigators
- American Heart Association, Fall 1984
- College of Science and Engineering Distinguished Allumni Award
- Western Washington University, Spring 2019
No activities entered.
Cancer BiologyCBIO 552 (Fall 2022)
DissertationCBIO 920 (Fall 2022)
Oncogenes+Signal TrnsducCBIO 595A (Fall 2022)
Adv Topics in Cancer BiologyCBIO 553 (Spring 2022)
DissertationCBIO 920 (Spring 2022)
Research ConferenceCBIO 695A (Spring 2022)
Cancer BiologyCBIO 552 (Fall 2021)
DissertationCBIO 920 (Fall 2021)
Oncogenes+Signal TrnsducCBIO 595A (Fall 2021)
Research ConferenceCBIO 695A (Fall 2021)
Adv Topics in Cancer BiologyCBIO 553 (Spring 2021)
Cancer BiologyCBIO 552 (Fall 2020)
Oncogenes+Signal TrnsducBIOC 595A (Fall 2020)
Oncogenes+Signal TrnsducCBIO 595A (Fall 2020)
Adv Topics in Cancer BiologyCBIO 553 (Spring 2020)
Honors ThesisMCB 498H (Spring 2020)
Cancer BiologyCBIO 552 (Fall 2019)
Honors ThesisMCB 498H (Fall 2019)
Oncogenes+Signal TrnsducCBIO 595A (Fall 2019)
Adv Topics in Cancer BiologyCBIO 553 (Spring 2019)
Directed RsrchMCB 392 (Spring 2019)
Cancer BiologyCBIO 552 (Fall 2018)
Oncogenes+Signal TrnsducCBIO 595A (Fall 2018)
ThesisCMM 910 (Summer I 2018)
Adv Topics in Cancer BiologyCBIO 553 (Spring 2018)
Directed ResearchPSIO 492 (Spring 2018)
ThesisCMM 910 (Spring 2018)
Cancer BiologyCBIO 552 (Fall 2017)
Directed ResearchBIOC 492 (Fall 2017)
Directed ResearchPSIO 492 (Fall 2017)
Directed RsrchMCB 492 (Fall 2017)
Oncogenes+Signal TrnsducBIOC 595A (Fall 2017)
Oncogenes+Signal TrnsducCBIO 595A (Fall 2017)
ThesisCMM 910 (Fall 2017)
Adv Topics in Cancer BiologyCBIO 553 (Spring 2017)
Honors ThesisBIOC 498H (Spring 2017)
Senior CapstoneBIOC 498 (Spring 2017)
ThesisCMM 910 (Spring 2017)
Cancer BiologyCBIO 552 (Fall 2016)
Honors ThesisBIOC 498H (Fall 2016)
Oncogenes+Signal TrnsducCBIO 595A (Fall 2016)
Senior CapstoneBIOC 498 (Fall 2016)
DissertationCBIO 920 (Spring 2016)
Honors ThesisBIOC 498H (Spring 2016)
Senior CapstoneBIOC 498 (Spring 2016)
- Heimark, R. L. (2009). Regulation of N-cadherin in Epithelial-Mesenchymal Transition. In Molecular and Functional Diversities of Cadherin/Protocadherin. SignPost Publishing.
- Heimark, R. L., & Alexander, N. R. (2006). Regulation of Cadherins During Prostate Cancer Progression. In Cell Adhesion and Cytoskeletal Molecules in Metastasis(pp 47-68). Springer.
- Runyan, R. B., Heimark, R. L., Camenisch, T. D., & Barnett, J. (2005). Epithelial-mesenchymal transformation. In Rise and Fall of Epithelial Phenotype:Concepts of Epithelial-Mesenchymal Transition(pp 40-65). Molecular Biology Intelligence Unit.
- Heimark, R. L. (1993). Cell-cell Adhesion molecules of the blood brain barrier. In The Blood Brain Barrier: Cellular and Molecular Biology(pp 87-106).
- Heimark, R. L., & Schwartz, S. M. (1988). The role of cell-cell interaction in the regulation of Endothelial Cell Growth. In The Molecular and Cellular Biology of Wound Repair(pp 359-369). Plenum Press.
- Traut, R. R., Heimark, R. L., & Sun, T. T. (1974). Protein Topography of Ribosomal Subunits from Escherichia Coli. In Ribosomes(pp 271-308). Cold Spring Harbor.
- Cheung, L. S., Zheng, X., Wang, L., Baygents, J. C., Guzman, R., Schroeder, J. A., Heimark, R. L., & Zohar, Y. (2016). Adhesion dynamics of circulating tumor cells under shear flow in a bio-functionalized microchannel. JOURNAL OF MICROMECHANICS AND MICROENGINEERING, 21(5).
- Cieza-Rubio, N., Jie, T., & Heimark, R. L. (2015). Mechanistic Studies in the Inflammatory Response of Pancreatitis and Pancreatic Cancer: Role of Myeloid Derived Suppressor Cells. PANCREAS, 44(8), 1367.
- Rheinheimer, B., Vrba, L., Futcher, B. W., & Heimark, R. L. (2014). Alternative transcription of the SLIT2/ROBO1/miR-218-1 signaliong axis in pancreatic cancer. Cancer Research, 74(19), S127.
- Rheinheimer, B., Vrba, L., Futscher, B., & Heimark, R. L. (2013). Epigenetic silencing alters the SLIT2/ROBO1/miR-218-1 signaling axis in pancreatic cancer. CANCER RESEARCH, 72(13 Supplenent), B13.
- Chandramouli, A., Onyeagucha, B. C., Mercado-Pimentel, M. E., Stankova, L., Shahin, N. A., LaFleur, B. J., Heimark, R. L., Bhattacharyya, A. K., & Nelson, M. A. (2012). MicroRNA-101 (miR-101) post-transcriptionally regulates the expression of EP4 receptor in colon cancers. Cancer biology & therapy, 13(3), 175-83.More infoExpression of the PGE2 receptor, EP4, is up-regulated during colorectal carcinogenesis. However the mechanism leading to deregulation of the EP4 receptor is not known. The present study was conducted to investigate the regulation of EP4 receptor by miRNAs.
- Doetschman, T., Barnett, J. V., Runyan, R. B., Camenisch, T. D., Heimark, R. L., Granzier, H. L., Conway, S. J., & Azhar, M. (2012). Transforming Growth Factor beta signaling in adult cardiovascular diseases and repair. Cell and Tissue Research, 347(1), 203-223.
- Cheung, L. S., Zheng, X., Wang, L., Guzman, R., Schroeder, J. A., Heimark, R. L., Baygents, J. C., & Zohar, Y. (2010). Kinematics of Specifically Captured Circulating Tumor Cells in Bio-Functionalized Microchannels. JOURNAL OF MICROELECTROMECHANICAL SYSTEMS, 19(4), 752-763.
- Lee, L., Heimark, R., Baygents, J., & Zohar, Y. (2010). Self-aligned immobilization of proteins utilizing PEG patterns. NANOTECHNOLOGY, 17(4), S29-S33.
- Vrba, L., Jensen, T. J., Garbe, J. C., Heimark, R. L., Cress, A. E., Dickinson, S., Stampfer, M. R., & Futscher, B. W. (2010). Role for DNA methylation in the regulation of miR-200c and miR-141 expression in normal and cancer cells. PloS one, 5(1), e8697.More infoThe microRNA-200 family participates in the maintenance of an epithelial phenotype and loss of its expression can result in epithelial to mesenchymal transition (EMT). Furthermore, the loss of expression of miR-200 family members is linked to an aggressive cancer phenotype. Regulation of the miR-200 family expression in normal and cancer cells is not fully understood.
- Moran, C. M., Garriock, R. J., Miller, M. K., Heimark, R. L., Gregorio, C. C., & Krieg, P. A. (2008). Expression of the fast twitch troponin complex, fTnT, fTnI and fTnC, in vascular smooth muscle. Cell motility and the cytoskeleton, 65(8), 652-61.More infoIt is generally believed that proteins of the troponin complex are not expressed in smooth muscle. We have directly assayed for expression of troponin transcripts in mouse vascular smooth muscle and found that troponin sequences normally associated with fast twitch skeletal muscle (fTnT, fTnI, fTnC) were present at significant levels in the thoracic aorta. In situ hybridization experiments demonstrated that fTnT, fTnI and fTnC transcripts were expressed in the smooth muscle layer of mouse blood vessels of all sizes. Protein blot analysis using rat tissue showed that at least two members of the troponin complex, Troponin T and Troponin I, were translated in vascular smooth muscle of the aorta. Finally, immuno-fluorescence microscopy of rat aortic smooth muscle revealed that TnT and TnI are localized in a unique pattern, coincident with the distribution of tropomyosin. It seems likely therefore, that a complete troponin complex is expressed in vascular smooth muscle and is associated with the contractile machinery of the cell. These observations raise the possibility that troponins play a role in regulation of smooth muscle function.
- Cherukuri, D. P., Chen, X. B., Goulet, A., Young, R. N., Han, Y., Heimark, R. L., Regan, J. W., Meuillet, E., & Nelson, M. A. (2007). The EP4 receptor antagonist, L-161,982, blocks prostaglandin E2-induced signal transduction and cell proliferation in HCA-7 colon cancer cells. Experimental cell research, 313(14), 2969-79.More infoAccumulating evidence indicates that elevated levels of prostaglandin E(2) (PGE(2)) can increase intestinal epithelial cell proliferation, and thus play a role in colorectal tumorigenesis. PGE(2) exerts its effects through four G-protein-coupled PGE receptor (EP) subtypes, named the EP1, EP2, EP3, and EP4. Increased phosphorylation of extracellular regulated kinases (ERK1/2) is required for PGE(2) to stimulate cell proliferation of human colon cancer cells. However, the EP receptor(s) that are involved in this process remain unknown. We provide evidence that L-161,982, a selective EP4 receptor antagonist, completely blocks PGE(2)-induced ERK phosphorylation and cell proliferation of HCA-7 cells. In order to identify downstream target genes of ERK1/2 signaling, we found that PGE(2) induces expression of early growth response gene-1 (EGR-1) downstream of ERK1/2 and regulates its expression at the level of transcription. PGE(2) treatment induces phosphorylation of cyclic AMP response element binding protein (CREB) at Ser133 residue and CRE-mediated luciferase activity in HCA-7 cells. Studies with dominant-negative CREB mutant (ACREB) provide clear evidence for the involvement of CREB in PGE(2) driven egr-1 transcription in HCA-7 cells. In conclusion, this study reveals that egr-1 is a target gene of PGE(2) in HCA-7 cells and is regulated via the newly identified EP4/ERK/CREB pathway. Finally our results support the notion that antagonizing EP4 receptors may provide a novel therapeutic approach to the treatment of colon cancer.
- Cheung, L. S., Zheng, X., Stopa, A., Baygents, J. C., Guzman, R., Schroeder, J. A., Heimark, R. L., & Zohar, Y. (2006). Detachment of captured cancer cells under flow acceleration in a bio-functionalized microchannel. LAB ON A CHIP, 9(12), 1721-1731.
- Cox, C. M., D'Agostino, S. L., Miller, M. K., Heimark, R. L., & Krieg, P. A. (2006). Apelin, the ligand for the endothelial G-protein-coupled receptor, APJ, is a potent angiogenic factor required for normal vascular development of the frog embryo. Developmental biology, 296(1), 177-89.More infoThe peptide growth factor apelin is the high affinity ligand for the G-protein-coupled receptor APJ. During embryonic development of mouse and frog, APJ receptor is expressed at high levels in endothelial precursor cells and in nascent vascular structures. Characterization of Xenopus apelin shows that the sequence of the bioactive region of the peptide is perfectly conserved between frogs and mammals. Embryonic expression studies indicate that apelin is expressed in, or immediately adjacent to, a subset of the developing vascular structures, particularly the intersegmental vessels. Experimental inhibition of either apelin or APJ expression, using antisense morpholino oligos, results in elimination or disruption of intersegmental vessels in a majority of embryos. In gain of function experiments, apelin peptide is a potent angiogenic factor when tested using two in vivo angiogenesis assays, the frog embryo and the chicken chorioallantoic membrane. Furthermore, studies using the mouse brain microvascular cell line bEnd.3 show that apelin acts as a mitogenic, chemotactic and anti-apoptotic agent for endothelial cells in culture. Finally, we show that, similar to a number of other angiogenic factors, expression of the apelin gene is increased under conditions of hypoxia. Taken together, these studies indicate that apelin is required for normal vascular development in the frog embryo and has properties consistent with a role during normal and pathological angiogenesis.
- Heimark, R., Alexander, N. R., Tran, N. L., Rekapally, H., Summers, C. E., Glackin, C., & Heimark, R. L. (2006). N-cadherin gene expression in prostate carcinoma is modulated by integrin-dependent nuclear translocation of Twist1. Cancer research, 66(7).More infoThe gain of N-cadherin expression in carcinomas has been shown to be important in the regulation of cell migration, invasion, and survival. Here, we show that N-cadherin mRNA expression in PC-3 prostate carcinoma cells is dependent on beta(1) integrin-mediated cell adhesion to fibronectin and the basic helix-loop-helix transcription factor Twist1. Depletion of Twist1 mRNA by small interfering RNA resulted in decreased expression of both Twist1 and N-cadherin and the inhibition of cell migration. Whereas Twist1 gene expression was independent of beta(1) integrin-mediated adhesion, Twist1 protein failed to accumulate in the nuclei of cells cultured in anchorage-independent conditions. The increased nuclear accumulation of Twist1 following cell attachment was suppressed by treatment with an inhibitor of Rho kinase or a beta(1) integrin neutralizing antibody. The effect of Twist1 on induction of N-cadherin mRNA required an E-box cis-element located within the first intron (+2,627) of the N-cadherin gene. These data raise the possibility that integrin-mediated adhesion to interstitial matrix proteins during metastasis differentially regulates the nuclear/cytoplasmic translocation and DNA binding of Twist1, activating N-cadherin transcription.
- Lee, L. M., Heimark, R. L., Baygents, J. C., & Zohar, Y. (2006). Self-aligned immobilization of proteins utilizing PEG patterns. Nanotechnology, 17(4), S29-33.More infoA novel self-aligned method to selectively immobilize proteins on a silicon dioxide surface is developed in conjunction with a standard lift-off patterning technique of a PEG layer. The approach is designed to photolithographically pattern regions that specifically bind target proteins and particles, surrounded by regions that suppress non-specific attachment of bio-species. The physical and biological properties of the derivatized surfaces at the end of the fabrication process are characterized.
- Lee, L. M., Heimark, R. L., Guzman, R., Baygents, J. C., & Zohar, Y. (2006). Low melting point agarose as a protection layer in photolithographic patterning of aligned binary proteins. LAB ON A CHIP, 6(8), 1080-1085.
- Lee, L. M., Heimark, R. L., Guzman, R., Baygents, J. C., & Zohar, Y. (2006). Low melting point agarose as a protection layer in photolithographic patterning of aligned binary proteins. Lab on a chip, 6(8), 1080-5.More infoA novel photolithography method to build aligned patterns of two different proteins is presented. Chessboard patterns of 125 microm x 125 microm squares are constructed on a silicon dioxide substrate, using standard photoresist chemistries in combination with low-temperature oxygen plasma etching. Low-melting-point agarose (LMPA) is used to protect underlying protein layers and, at the appropriate stage, the digestive enzyme GELase (EPICENTRE) is used to selectively remove the prophylactic LMPA layers. Two antibodies, mouse-IgG and human-IgG, were immobilized and patterned by this procedure. The patterned antibodies maintained the specificity of their antigen-antibody binding, as demonstrated by fluorescence microscopy. In addition, normalized fluorescence intensity profiles illustrate that the patterned proteins layers are uniform (standard deviations below 0.05). Finally, a trypsin activity test was conducted to probe the effect of the patterning protocol on immobilized enzymes; the results imply that this photolithographic process using LMPA as a protection layer preserves 70% of immobilized enzyme activity.
- Derbyshire, Z. E., Haltfer, U. M., Heimark, R. L., & Vaillincourt, R. R. (2006). Angiotensin II stimulated transcription of cyclooxygenase II is regulated by a novel kinase cascade involving Pyk2, MEKK4 and annexin II. Molecular and Cellular Biochemistry, 271(1-2), 77-90.
- Vokes, S. A., Yatskievych, T. A., Heimark, R. L., Antin, P., & Krieg, P. (2004). Hedgehog Signaling is Essential for Endothelial Tube formation during Vasculogenesis. Development, 131(17), 4371-4380.
- Wessells, H., King, S. H., Schmelz, M., Nagle, R. B., & Heimark, R. L. (2004). Immunohistochemical comparison of vascular and sinusoidal adherens junctions in cavernosal endothelium. Urology, 63(1), 201-6.More infoTo characterize endothelial cell-to-cell junctions in the sinusoids and microvasculature of the corpus cavernosum.
- Alexander, N. R., Tran, N. L., & Heimark, R. L. (2002). Co-expression of N-cadherin and E-cadherin in prostate carcinoma cells promotes a migratory phenotype. Proceedings of the American Association for Cancer Research, 43, 368.
- Heimark, R. L., Koachar, S., & Stamer, W. D. (2002). Human Schlem'scancal cells express the endothelial adherens junction proteins VE-cadherin and PECAM-1. Current Eye Research, 25(6), 299-308.
- Heimark, R., Tran, N. L., Adams, D. G., Vaillancourt, R. R., & Heimark, R. L. (2002). Signal transduction from N-cadherin increases Bcl-2. Regulation of the phosphatidylinositol 3-kinase/Akt pathway by homophilic adhesion and actin cytoskeletal organization. The Journal of biological chemistry, 277(36).More infoAssociated with the metastatic progression of epithelial tumors is the dynamic regulation of cadherins. Whereas E-cadherin is expressed in most epithelium and carcinomas, recent studies suggest that the up-regulation of other cadherin subtypes in carcinomas, such as N-cadherin, may function in cancer progression. We demonstrate that a signal transduction cascade links the N-cadherin.catenin adhesion complex to up-regulation of the anti-apoptotic protein Bcl-2. In suspension, aggregates of DU-145 cells, an E-cadherin expressing human prostate carcinoma line, survive loss of integrin-dependent adhesion by a different anti-apoptotic signaling pathway than the N-cadherin expressing lines PC3 and PC3N. N-cadherin intercellular adhesion mediates a 3.5-fold increase in Bcl-2 protein expression, whereas the level of the proapoptotic protein Bax remains constant. Only N-cadherin ligation in PC3 cells, which express both N-cadherin and E-cadherin, is sufficient to induce activation of Akt/protein kinase B. N-cadherin homophilic ligation initiates phosphatidylinositol 3-kinase-dependent activation of Akt resulting in Akt phosphorylation of Bad on serine 136. Following N-cadherin homophilic adhesion phosphatidylinositol 3-kinase was identified in immunoprecipitates of the N-cadherin.catenin complex. The recruitment of phosphatidylinositol 3-kinase to the adhesion complex is dependent on ligation of N-cadherin and an organized actin cytoskeleton because cytochalasin D blocks the recruitment. We propose that N-cadherin homophilic adhesion can initiate anti-apoptotic signaling, which enhances the Akt cell survival pathway in metastatic cancer.
- Bair, E. L., Massey, C. P., Tran, N. L., Borchers, A. H., Heimark, R. L., Cress, A. E., & Bowden, G. T. (2001). Integrin- and cadherin-mediated induction of the matrix metalloprotease matrilysin in cocultures of malignant oral squamous cell carcinoma cells and dermal fibroblasts. Experimental cell research, 270(2), 259-67.More infoMatrilysin is a matrix metalloprotease (MMP) overexpressed in a number of cancers including skin, head and neck squamous cell carcinomas, and prostate and colon adenocarcinomas. Matrilysin has been shown to play a role in the degradation of the basement membrane that separates epithelium from stroma allowing tumor cells to intravasate into the bloodstream and metastasize. Here, we show that an oral squamous cell carcinoma cell line (SCC-25) expresses low levels of promatrilysin when cultured alone. However, when SCC-25 cells are cocultured with human foreskin fibroblasts (HFF), there is a 40-fold induction of promatrilysin expression. We tested whether this induction of promatrilysin expression was due to the release of paracrine factors, cell-cell interactions, or cell-matrix interactions. Our results indicate induced promatrilysin expression is the result of both cell-cell and cell-matrix interactions. We demonstrate that beta1 integrins as well as cadherins, specifically N-cadherin and E-cadherin, are involved in the induction of promatrilysin expression. Our results are of general interest in relation to the regulation of MMP expression through cell surface receptor regulation. Further investigation may lead to the identification of novel targets for suppression of invasion and metastasis in oral tumors.
- Westerband, A., Crouse, D., Richter, L. C., Aguirre, M. L., Wixon, C. C., James, D. C., Mills, J. L., Hunter, G. C., & Heimark, R. L. (2001). Vein adaptation to arterialization in an experimental model. Journal of vascular surgery, 33(3), 561-9.More infoThe events preceding myointimal thickening in vein grafts after vascular reconstructions are not well characterized. Indeed, the injury response associated with vein graft arterialization may be different than that observed in the balloon angioplasty model. Therefore, we used a rat model to study the early cellular response after arterialization of vein grafts.
- Hurst V, I. V., Goldberg, P. L., Minnear, F. L., Heimark, R. L., & Vincent, P. A. (1999). Rearrangement of adherens junctions by transforming growth factor-beta1: role of contraction. The American journal of physiology, 276(4 Pt 1), L582-95.More infoThe signal transduction pathways that lead to disruption of pulmonary endothelial monolayer integrity by transforming growth factor-beta1 (TGF-beta1) have not been elucidated. The purpose of this investigation was to determine whether disassembly of the adherens junction is temporally associated with the TGF-beta1-induced decrease in pulmonary endothelial monolayer integrity. Measurement of albumin clearance and electrical resistance showed that monolayer integrity started to decrease between 1 and 2 h post-TGF-beta1 treatment and continued to slowly decrease over the next 6 h. Immunofluorescence microscopy of monolayers between 2 and 3 h post-TGF-beta1 showed that beta-catenin, plakoglobin, alpha-catenin, and cadherin-5 were colocalized both at the cell periphery and in newly formed bands that are perpendicular to the cell-cell border. At 4 h post-TGF-beta1, cells began separating; however, beta- and alpha-catenin, plakoglobin, and cadherin-5 could still be found at the cell periphery at areas of cell separation and in strands between separated cells. By 8 h, these junctional proteins were no longer present at the cell periphery at areas of cell separation. The myosin light chain kinase inhibitor KT-5926 prevented the TGF-beta1-induced change in integrity but did not inhibit the formation of actin stress fibers or the formation of bands containing adherens junction proteins that were perpendicular to the cell-cell junction. Overall, these results suggest that adherens junction disassembly occurs after cell separation during TGF-beta1-induced decreases in pulmonary endothelial monolayer integrity and that the loss of integrity may be due to the activation of a myosin light chain kinase-dependent signaling cascade.
- Tran, N. L., Nagle, R. B., Cress, A. E., & Heimark, R. L. (1999). N-cadherin expression in human prostate carcinoma cell lines- An Epithelial-mesenchymal transformation mediating adhesion with stromal cells. American Journal of Pathology, 155(3), 787-798.
- Westerband, A., Mills, J. L., Hunter, G. C., Gentile, A. T., Ihnat, D., & Heimark, R. L. (1998). Topography of cell replication in human vein graft stenoses. Circulation, 98(19 Suppl), II325-9; discussion II329-30.More infoAnalysis of the cellular composition of human autogenous vein graft lesions at the time of revision provides an opportunity to identify the cellular processes leading to the development of stenosis in humans after vascular reconstruction.
- Haselton, F. R., & Heimark, R. L. (1997). Role of cadherins 5 and 13 in the aortic endothelial barrier. Journal of cellular physiology, 171(3), 243-51.More infoWe investigated the role of the cadherins 5 and 13 in the solute barrier formed by aortic endothelial cells in vitro. In confluent monolayers of bovine aortic endothelial cells, immunofluorescence with antibodies to the external domain of cadherin 5 (Mab 9H7) or to cadherin 13 (Mab Ec6C10) found staining for both cadherins at endothelial cell borders. Western blotting with an antibody to the characteristic cadherin cytoplasmic tail or with an antibody to the extracellular domain of cadherin 5 revealed a single 125 kD protein band. A second larger band was found at 130 kD with the anti-cadherin 13 Mab which was not recognized by an antibody to the cadherin cytoplasmic tail. A calcium switch strategy was used to investigate the involvement of these cadherins in the endothelial barrier. Changes in the permeability of small solutes in an endothelial cell column produced by a decrease in calcium concentration followed by a return to normal calcium, with or without antibody, were recorded. We found that anti-cadherin 5 IgG (10 micrograms/ml) interfered with the reforming of interendothelial junctions after restoration of calcium at every time point tested for a total of 45 min after restoration of calcium. The anti-cadherin 13 IgG (10 micrograms/ml) did not block reforming of the endothelial barrier in a similar manner. The presence of this antibody delayed only by 15 min the restoration of the normal barrier. Without calcium switch, addition of either monoclonal antibody (10 micrograms/ml) to the endothelial cell column had no effect on solute permeability. These results suggest that cadherin 5 in bovine aortic endothelial cells has a major functional role in forming the calcium-sensitive endothelial junction in vitro and may play an important role in the normal structure and function of the in vivo barrier.
- Schram, C. A., Runyan, R. R., & Heimark, R. L. (1997). Regulation of cadherin 5 during epithelial mesenchymal transformation of atrioventricular endocardium. Molecular Biology of the Cell, 8, 1899.
- Westerband, A., Mills, J. L., Marek, J. M., Heimark, R. L., Hunter, G. C., & Williams, S. K. (1997). Immunocytochemical determination of cell type and proliferation rate in human vein graft stenoses. Journal of vascular surgery, 25(1), 64-73.More infoVascular reconstructions are prone to fail as a result of the development of stenotic lesions, which have historically been attributed to myointimal hyperplasia. In animal models, these lesions are associated with marked proliferative smooth muscle cell (SMC) response to vascular injury. However, recent studies using sensitive immunocytochemical techniques in human lesions have generally failed to detect significant cellular proliferation. To clarify the role of cellular proliferation in humans, we characterized the cellular composition and proliferative index of 14 early infrainguinal vein graft stenoses.
- SCHRAMM, C., & HEIMARK, R. (1995). CADHERIN-5 EXPRESSION IN ENDOTHELIAL DIFFERENTIATION AND BLOOD-VESSEL GROWTH DURING EMBRYOGENESIS. DEVELOPMENTAL BIOLOGY, 170(2), 753.
- Tanihara, H., Kido, M., Obata, S., Heimark, R. L., Davidson, M., St John, T., & Suzuki, S. (1994). Characterization of cadherin-4 and cadherin-5 reveals new aspects of cadherins. Journal of cell science, 107 ( Pt 6), 1697-704.More infoSeveral properties of cadherin-4 and cadherin-5 were characterized by using the cDNA transfection approach. The proteins of both cadherins had a relative molecular mass of about 130 kDa and were present at the cell periphery, especially at cell-cell contact sites. These cadherins were easily digested with trypsin, and Ca2+ protected cadherin-4, but not cadherin-5, from the digestion. In immunoprecipitation, cadherin-4 co-precipitated with two major proteins of 105 kDa and 95 kDa, respectively. The 105 kDa and the 95 kDa proteins are likely to correspond to alpha- and beta-catenins. Cadherin-5 co-precipitated with only one major protein of 95 kDa, but seems to associate with the 105 kDa protein. On the other hand, plakoglobin or gamma-catenin did not co-precipitate well with either cadherin-4 or cadherin-5 in immunoprecipitation, but plakoglobin also appears to associated weakly with these cadherins. Cadherin-4 transfectants aggregated within 30 minutes in a cell aggregation assay, but cadherin-5 transfectants did not aggregate under the same conditions. Furthermore, the transfectants of chimeric cadherin-4 with cadherin-5 cytoplasmic domain showed cell aggregation activity comparable to that of wild-type cadherin-4 transfectants, whereas the transfectants of chimeric cadherin-5 with cadherin-4 cytoplasmic domain did not show appreciable cell aggregation, suggesting that the extracellular domains of cadherins, in conjunction with their cytoplasmic domains, play an important role in cell aggregation activity. These results show that cadherin-4 is very similar to the classical cadherins, whereas cadherin-5 is functionally as well as structurally distinct from classical cadherins.
- Tanihara, H., Sano, K., Heimark, R. L., St John, T., & Suzuki, S. (1994). Characteristic Features of Cadherin Extracellular Domain and provides further Evidence for 2 Structurall Different types of Cadherin. Cell Adhesion and Communication, 2(1), 15-26.
- Tanihara, H., Sano, K., Heimark, R. L., St John, T., & Suzuki, S. (1994). Cloning of five human cadherins clarifies characteristic features of cadherin extracellular domain and provides further evidence for two structurally different types of cadherin. Cell adhesion and communication, 2(1), 15-26.More infoThe entire coding sequences for five possible human cadherins, named cadherin-4, -8, -11, -12 and -13, were determined. The deduced amino acid sequences of cadherin-4 and cadherin-13 showed high homology with those of chicken R-cadherin or chicken T-cadherin, suggesting that cadherin-4 and cadherin-13 are mammalian homologues of the chicken R-cadherin or T-cadherin. Comparison of the extracellular domain of these proteins with those of other cadherins and cadherin-related proteins clarifies characteristic structural features of this domain. The domain is subdivided into five subdomains, each of which contains a cadherin-specific motif characterized by well-conserved amino acid residues and short amino acid sequences. Moreover, each subdomain has unique features of its own. The comparison also provides additional evidence for two structurally different types of cadherins: the first type includes B-, E-, EP-, M, N-, P- and R-cadherins and cadherin-4; the second type includes cadherin-5 through cadherin-12. Cadherin-13 lacks the sequence corresponding to the cytoplasmic domain of typical cadherins, but the extracellular domain shares most of the features common to the extracellular domain of cadherins, especially those of the first type of cadherins, suggesting that cadherin-13 is a special type of cadherin. These results, and those of other recent cloning studies, indicate that many cadherins with different properties are expressed in various tissues of different organisms.
- Sano, K., Tanihara, H., Heimark, R. L., Obata, S., Davidson, M., St John, T., Taketani, S., & Suzuki, S. (1993). Protocadherins: a large family of cadherin-related molecules in central nervous system. The EMBO journal, 12(6), 2249-56.More infoUsing the polymerase chain reaction, we have isolated numerous rat and human cDNAs of which the deduced amino acid sequences are highly homologous to the sequences of the extracellular domain of cadherins. The entire putative coding sequences for two human proteins defined by two of these cDNAs have been determined. The overall structure of these molecules is very similar to that of classic cadherins, but they have some unique features. The extracellular domains are composed of six or seven subdomains that are very similar to those of cadherins, but have characteristic properties. The cytoplasmic domains, on the other hand, have no significant homology with those of classic cadherins. Since various cDNAs with almost identical features were obtained also from Xenopus, Drosophila and Caenorhabditis elegans, it appears that similar molecules are expressed in a variety of organisms. We have tentatively named these proteins protocadherins. They are highly expressed in brain and their expression appears to be developmentally regulated. The proteins expressed from the two full-length cDNAs in L cells were approximately 170 or 150 kDa in size, and were localized mainly at cell-cell contact sites. Moreover, the transfectants showed cell adhesion activity.
- Coffin, J. D., Harrison, J., Schwartz, S., & Heimark, R. (1991). Angioblast differentiation and morphogenesis of the vascular endothelium in the mouse embryo. Developmental biology, 148(1), 51-62.More infoBandeiraea simplicifolia B4 isolectin (BSLB4) and polyclonal antisera against von Willebrand factor (VWF) were used to study the origin of endothelial cells and their organization into blood vessels in the postimplantation mouse embryo. Examination of BSLB4-stained whole mounted and sectioned embryos revealed intense staining of the endothelium, highlighting large vessels, capillaries, and many individual cells. Dorsal aorta formation was first obvious at E7 when many lectin-positive cells appeared in paraxial and lateral plate mesoderm. As development proceeded to E8, BSLB4-positive cells became organized into craniocaudal lines destined to become the aorta proper. At E9, BSLB4 stained all vessels of the embryo including the dorsal aorta, the intersomitic arteries, and the endocardium. VWF expression was not detected until E8 when BSLB4/VWF double-stained sections revealed the dorsal aortae as the first VWF-positive vessels, while other endothelium visible with BSLB4 remained negative for VWF immunostaining. By E12 many other vessels became VWF-positive, including the aortic arches, the intersomitic arteries, and the cardinal veins. However, many angioblasts and capillaries remained VWF-negative, reflecting the heterogeneous expression of VWF among endothelium that has been reported in adults of other species. The histochemical data reported here support the conclusions of earlier avian studies by showing distinct vascular patterns in the initial formation of vessels from isolated angioblasts (vasculogenesis), followed by the extension and organization of the initial vascular structures (angiogenesis). Moreover, our data suggest that the endothelium arises from distinct VWF-positive sources associated with the dorsal aorta, as well as VWF-negative sources associated with other vessels in the embryo.
- Heimark, R. L. (1991). Calcium-Dependent and Calcium-Independent Cell Adhesion Molecules in the Endothelium. Annals of the New York Academy of Sciences, 614, 229-239.
- Bavisotto, L. M., Schwartz, S. M., & Heimark, R. L. (1990). Modulation of Ca2(+)-dependent intercellular adhesion in bovine aortic and human umbilical vein endothelial cells by heparin-binding growth factors. Journal of cellular physiology, 143(1), 39-51.More infoCultured endothelial cells have been shown to possess two mechanisms of intercellular adhesion: Ca2(+)-dependent and Ca2(+)-independent. We report here that growth of bovine aortic endothelial cells (BAEC) in complete medium containing purified basic fibroblast growth factor (bFGF, 6 ng/ml) results in loss of Ca2(+)-dependent intercellular adhesion. In the presence of heparin (90 micrograms/ml), this effect is reproduced upon treatment with acidic fibroblast growth factor (aFGF, 6 ng/ml) or endothelial cell growth supplement (ECGS, 100 micrograms/ml), in both human umbilical vein endothelial cells (HUVEC) and BAEC. Treatment at these doses with aFGF in the absence of heparin or with heparin alone is without significant effect. Loss of Ca2(+)-dependent adhesion following treatment of cells with heparin-binding growth factors (HBGFs) is prevented by pre-treatment of cell layers with cycloheximide. The Ca2(+)-independent adhesion mechanism is unaffected by HBGF treatment. Exposure of endothelial cells to HBGFs, moreover, prevents the eventual establishment of quiescence in growing cultures and restimulates replication in confluent cultures that have reached a final density-inhibited state. Addition of bFGF alone or aFGF + heparin at these doses results in a 4-fold increase in DNA synthesis over untreated control cultures at saturation density as reflected by thymidine index. A single addition of bFGF (6 ng/ml) to untreated quiescent confluent BAEC monolayers results in an increase in 3H-TdR incorporation reaching a peak at 22 hours with a parallel loss of Ca2(+)-dependent adhesiveness. Fluorescent staining with rhodamine-phalloidin demonstrates an altered distribution of polymerized F-actin in the bFGF-treated monolayers, marked by disruption of the dense peripheral microfilament bands retained by untreated confluent monolayers. Together, these results indicate that the mitogenic effect of HBGFs in cultured endothelial cells is associated with a "morphogenic" set of responses, perhaps dependent on breakdown of calcium-dependent cell-cell contacts.
- Heimark, R. L., Schwartz, S. M., & Majesky, M. W. (1990). Developmental Mechanisms Underlying Pathology of Arteries. Physiological Reviews, 70(4), 1177-1209.
- Chen, C. S., Thiagarajan, P., Schwartz, S. M., Harlan, J. M., & Heimark, R. L. (1987). The platelet glycoprotein IIb/IIIa-like protein in human endothelial cells promotes adhesion but not initial attachment to extracellular matrix. The Journal of cell biology, 105(4), 1885-92.More infoOn platelets the membrane glycoprotein IIb/IIIa complex (GPIIb/IIIa) functions in adhesive interactions with fibrinogen, von Willebrand factor, and fibronectin. However, the function of GPIIb/IIIa-like proteins on endothelial cells, as well as the ligand(s) the complex binds, is unknown. Using a highly specific polyclonal antibody we have explored the function of GPIIb/IIIa-like proteins on human umbilical vein endothelial cells (HUVE). Analysis by immunoblotting shows that this antiserum recognizes the endothelial GPIIIa-like protein of the complex. The IgG fraction of the polyclonal antiserum and its Fab' fragments detach confluent and subconfluent HUVE from extracellular substrata. The effect of the anti-GPIIb/IIIa IgG is not toxic as the detached cells maintain their viability after trypsinization and replating. Anti-GPIIb/IIIa IgG does not inhibit HUVE binding to extracellular matrix or purified fibronectin in an attachment assay despite the presence of intact GPIIb/IIIa on HUVE detached from substrate by various methods. Apparently, the GPIIb/IIIa-like protein on HUVE is important in normal HUVE adhesion to the extracellular matrix, but it is not required in the initial attachment of HUVE to extracellular matrix.
- Funakoshi, T., Heimark, R. L., Hendrickson, L. E., McMullen, B. A., & Fujikawa, K. (1987). Human Placental Anticoagulant Protein Isolation and Characterization. Biochemistry, 26(17), 5572-5578.
- Heimark, R. L., Twardzik, D. R., & Schwartz, S. M. (1986). Inhibition of Endothelial Regeneration by Type Beta Transforming Growth Factor from Platelets. Science, 233(4768), 1078-1080.
- Heimark, R. L., & Schwartz, S. M. (1985). The Role of Membrane: Membraine Inteactions in the Regulation of Endothelial Cell Growth. Journal of Cell Biology, 100(6), 1934-1940.
- Gabbiani, G., Gabbiani, F., Heimark, R. L., & Schwartz, S. M. (1984). Organization of actin cytoskeleton during early endothelial regeneration in vitro. Journal of cell science, 66, 39-50.More infoThe pattern of early cell movement after an experimental 'wound' and the organization of actin in stationary and moving cultured endothelial cells have been studied by means of: time-lapse photography; indirect immunofluorescence using anti-actin antibodies with and without pretreatment with the actin destabilizing factor present in human plasma; and differential centrifugation and densitometric analysis of stained sodium dodecylsulphate/polyacrylamide gels in order to evaluate the total and relative amounts of G and F-actin. Up to 5 h after a single scratch, movement consists of a coordinate spreading and translocation of a band of about 10 cells from the wound edge. Compared to stationary cells, moving endothelial cells show: no significant changes in the intensity and distribution of immunofluorescent staining with anti-actin antibodies, but an increased sensitivity of cytoplasmic actin, including stress fibres, to the actin-destabilizing factor purified from human plasma; and no significant change in the total amount of actin, but a decreased relative amount of F-actin and a corresponding increased relative amount of G-actin. We conclude that endothelial cell movement in vitro is accompanied by a rapid change in the state of actin organization characterized by an overall decrease in cytoplasmic F-actin.
- Heimark, R. L., & Schwartz, S. M. (1984). Binding of Coagulation Factor IX and Factor X to the Endothelial Cell Surface. Biochemical and Biophysical Research Communication, 111(2), 723-731.
- Kurachi, K., Ohkubo, I., Heimark, R. L., Fujikawa, K., & Davie, E. W. (1983). Initiation of Intrinsic Blood Coagulation. Advances In Experimental Medicine and Biolofy, 156, 39-44.
- Kurachi, K., Ohkubo, I., Heimark, R. L., Fujikawa, K., & Davie, E. W. (1983). Initiation of intrinsic blood coagulation. Advances in experimental medicine and biology, 156, 39-44.
- Heimark, R. L., & Davie, E. W. (1981). Bovine and Human Plasma Prekallikrein. Methods In Enzymology, 80(Part C), 157-172.
- McRae, B. J., Kurachi, K., Heimark, R. L., Fujikawa, K., Davie, E. W., & Powers, J. C. (1981). Mapping the active sites of bovine thrombin, factor IXa, factor Xa, factor XIa, factor XIIa, plasma kallikrein, and trypsin with amino acid and peptide thioesters: development of new sensitive substrates. Biochemistry, 20(25), 7196-206.More infoThe subsite specificities of bovine factor IXa, factor Xa, factor XIa, factor XIIa, thrombin, plasma kallikrein, and trypsin were mapped with amino acid, dipeptide, and longer peptide thioester substrates. Each substrate contained a P1 Arg residue. The P1' residues included thiol residues which are analogues of valine, leucine, and isoleucine, respectively, and the P2 residue included 12 representative amino acid residues. Longer substrates with the sequence at the antithrombin III reactive site and at the zymogen activation site of various coagulation factors were also studied. The enzymatic hydrolysis of the thioesters was measured in the presence of 4,4'-dithiodipyridine which provides a very sensitive assay for the free thiol. The thioesters were excellent substrates for the coagulation factors studied, and the kcat/Km values for the best thioester substrates were higher than those previously reported for most of these enzymes. Thrombin and plasma kallikrein were the most active of the coagulation factors toward the thioester substrates. The best substrate for thrombin was Z-Gly-Arg-SCH2C6H5, although substrates containing proline in the P2 position were also quite effective. Some of the better substrates for plasma kallikrein had a P2 Phe or Trp residue. Factor IXa was the least reactive of the coagulation factors and hydrolyzed only four of the dipeptide thioesters. Substrates with bulky hydrophobic groups such as Phe or Trp in the P2 position were the most reactive with factor IXa. Factor Xa hydrolyzed all the thioester substrates tested, the most reactive being Z-Gly-Arg-SCH2C6H5. This is consistent with the fact that glycine and arginine are present in the P2 and P1 positions, respectively, of the factor Xa sensitive bonds in prothrombin which is the physiological substrate for factor Xa. Bovine factor XIa showed the least amount of specificity of the various coagulation factors and was quite reactive toward all of the thioester substrates. The most sensitive substrate for this enzyme was also Z-Gly-Arg-SCH2C6H5. Factor XIIa preferred the dipeptide with a P2 Phe, although the simpler thioester Z-Arg-SCH2CH(CH3)2 was more reactive. Trypsin hydrolyzed all of the thioester substrates at a high rate and showed little substrate specificity. With all enzymes studied, extension of the thioester substrate beyond P2 or the P1' thiol leaving group did not lead to an improvement in hydrolysis. Due to their high kcat/Km values and the ease of detecting the thiol leaving group, thioester substrates should be extremely useful for future studies of coagulation proteases.
- Fujikawa, K., Heimark, R. L., Kurachi, K., & Davie, E. W. (1980). Activation of bovine factor XII (Hageman factor) by plasma kallikrein. Biochemistry, 19(7), 1322-30.
- Heimark, R. L., Kurachi, K., Fujikawa, K., & Davie, E. W. (1980). Surface Activation of Blood- Coagulation Fibrinolysis and Kinin Formation. Nature, 286(5772), 456-460.
- Heimark, R. L., & Davie, E. W. (1979). Isolation and Characterization of Bovine Plasma Prekallikrein (Fletcher Factor). Biochemistry, 18, 5743-5750.
- Heimark, R. L., Hershey, J. W., & Traut, R. R. (1976). Cross-linking of Initiation Factor IF2 to Proteins L7-L12 in the 70S Ribosomal Subunit. Journal of Biological Chemistry, 251(24), 7779-7784.
- Heimark, R. L., Kahan, L., Johnston, K., Traut, R. R., & Hershey, J. W. (1976). Cross-linking of Initiation Factor IF3 to Proteins of Escherichia coli 30S Ribosomal Subunit. Journal of Molecular Biology, 105(2), 219-230.
- Bollen, A., Heimark, R. L., Cozzone, A., Traut, R. R., & Hershey, J. W. (1975). Cross-linking of initiation factor IF-2 to Escherichia coli 30 S ribosomal proteins with dimethylsuberimidate. The Journal of biological chemistry, 250(11), 4310-4.More infoThe 30 S ribosomal proteins near the binding site for initiation factor IF-2 in Escherichia coli were identified by allowing complexes of 30 S subunits, [32P]phosphoryl initiation factor IF-2 and nonradioactive initiation factors IF-1 and IF-3, to react with the protein cross-linking reagent dimethylsuberimidate. Noncross-linked initiation factors were removed by centrifugation of the complexes in buffer containing a high salt concentration; the protein was extracted from the pelleted particles; and cross-linked species containing initiation factor IF-2 and ribosomal proteins were partially purified by column chromatography on Sephadex G-75. The mixture of cross-linked products was analyzed by radioimmunodiffusion with antisera prepared against 20 individual 30 S ribosomal proteins S1, S2, S11, S12, S13, S14, and S19 was interpreted to mean that initiation factor IF-2 was present in covalent cross-linked complexes containing those proteins. The results imply that these 30 S ribosomal proteins are near the binding site for initiation factor IF-2.
- SUN, T., HEIMARK, R., & TRAUT, R. (1975). PROTEIN TOPOGRAPHY OF ESCHERICHIA-COLI 30S RIBOSOMAL-SUBUNIT - PRELIMINARY MODEL E-COLI-30S SUBUNIT-RIBOSOME-SPATIAL ARRANGEMENT OF PROTEINS. Molecular and Cellular Biochemistry, 6(1), 33-41.
- Zheng, X. J., Cheung, L. S., Jiang, L., Schroeder, J. A., Heimark, R. L., Baygents, J. C., Guzman, R., Zohar, Y., & , . (2011, 2011). DYNAMIC STATES OF ADHERING CANCER CELLS UNDER SHEAR FLOW IN AN ANTIBODY-FUNCTIONALIZED MICROCHANNEL. In 2011 IEEE 24TH INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS (MEMS), 849-852.
- Zheng, X. J., Cheung, L. S., Wang, L., Schroeder, J., Heimark, R. L., Baygents, J. C., Guzman, R., Zohar, Y., & , . (2011, 2010). QUANTITATIVE SPECIFIC BINDING OF BREAST CANCER CELLS IN AN ANTIBODY-FUNCTIONALIZED MICROCHAMBER ARRAY. In MEMS 2010: 23RD IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST, 939-942.
- Zheng, X., Cheung, S. L., Wang, L., Schroeder, J. A., Heimark, R. L., Baygents, J. C., Guzman, R., Zohar, Y., & , . (2004, 2010). SPECIFIC BINDING OF CANCER CELLS USING A MICROCHAMBER ARRAY FUNCTIONALIZED WITH ANTIBODIES. In IMECE 2009: PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION, VOL 12, PTS A AND B, 821-827.
- Cheung, L. S., Zheng, X. J., Stopa, A., Schroeder, J., Heimark, R. L., Baygents, J. C., Guzman, R., Zohar, Y., & , . (1997, 2009). FLOW ACCELERATION EFFECT ON CANCER CELL DEFORMATION AND DETACHMENT. In IEEE 22ND INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS (MEMS 2009), 431-434.
- Heimark, R. L., & Rubio, N. C. (2017, February). Myeloid Derived Suppressor Cells in the inflammatory Response of Pancreatitis and Pancreatic Cancer. American College of Surgeons. Las Vegas, NV.
- Abrams, A., Jie, T., Ong, E., Heimark, R. L., Bhattacharyya, A. K., & Patel, C. (2013, Feb/Spring). Characterization of Pancreatic Adenocarcinoma of Primary and Peritoneal Metastasis a Pilot Study Using Biomarkers for Metastasis (EMT). 2013 Americas Hepato-Pancreato-Biliary Association Meeting. Miami, FL.
- Wong, R. K., & Heimark, R. L. (1998, November). Proinflammatory cytokines TNF-alpha and IFN-gamma alter permeability and the cadherin-5/catenin complex via beta-catenin cleavage.. Cell Biology. San Francisco: The American Society for Cell Biology.
- Tatsuguchi, M., Rekapally, H., Summers, C., & Heimark, R. (1995, OCT 26). Id2 (Inhibitor of DNA binding) functions as a regulator of AV canal cushion mesenchyme in the morphogenesis of cardiac valves. CIRCULATION.
- Coffin, J. D., Harrison, J., Schwartz, S. M., & Heimark, R. L. (1989, DEC). Expression of Von Willebrand Factor in Endothelium of Post-Implantation Mouse Embryos. 29th Annual Meeting of American Society for Cell Biology. Houston, TX.
- Jie, T., Heimark, R. L., Rheinheimer, B., Jie, T., Heimark, R. L., & Rheinheimer, B. (2019, January). Deregulated growth factor signaling in pancreatic neuroendocrine liver metastasis. ASCO Gastrointestinal Cancers Symposium.
- Heimark, R. L., Riall, T. S., Rheinheimer, B. A., & Jie, T. (2019, February). Genomic Analysis of a Patient-Derived Organoid Model of Mixed Acinar/Neuroendocrine Cell Carcinoma. 2019 Academic Surgical Congress.
- Jie, T., Heimark, R. L., Rheinheimer, B. A., Heimark, R. L., Rheinheimer, B. A., & Jie, T. (2019, February). Functional Genomics of Pancreatic Neuroendocrine Tumor Metastases to the Liver. 2019 Academic Surgical Congress.
- Jie, T., Jie, T., Heimark, R. L., Heimark, R. L., Rheinheimer, B. A., & Rheinheimer, B. A. (2019, March). Deregulated growth factor signaling in pancreatic neuroendocrine liver metastasis. 2019 The Americas Hepato-Pancreato-Biliary Association.
- Schramm, C., Runyan, R., & Heimark, R. (1986, NOV). Regulation of cadherin 5 during epithelial-mesenchymal transformation of atrioventricular endocardium.. MOLECULAR BIOLOGY OF THE CELL.