Oncology & Cancer Biology
Danika Bannasch
Canine and Equine Genetics
Department of Population Health and Reproduction
(See also: Genetics/Genomics)
The Bannasch laboratory focuses on understanding the molecular mechanism of inherited naturally occurring diseases in companion animals. Prior to genome assemblies, my group successfully positionally cloned the gene for hyperuricosuria in dogs, and HERDA in horses. We subsequently successfully utilized genome wide association as a technique to determine the chromosomal location of many Mendelian and non-Mendelian disorders. Positional candidate genes were interrogated to define causal variants (Addison’s disease, Alaskan Husky encephalopathy, hoof wall separation syndrome, spinal dysraphism, Saluki encephalopathy, cleft palate and cleft lip, palate and syndactyly). We more recently have utilized whole genome sequencing approaches to define disease causing variants following GWAS (DCM and sudden death, an animal model of Robinow syndrome and coat color variants). We have also identified an unusual structural variant, an FGF4 retrogene, underlying canine chondrodystrophy and intervertebral disc disease. We followed this research with a molecular and bioinformatic investigation of retrogenes in animals. We identified and cataloged over 2000 canine retrogenes which are much more common than human or equine retrogenes. We continue to pursue this research through investigation into canine transposable elements (LINE-1) that mediate retrogene formation.
I really enjoy having summer research students. A summer research student would lean both wet lab molecular genetics techniques and gain skills in bioinformatics and computational genetic analysis. They would be involved in either variant identification for inherited diseases or working to understanding how dog transposable elements affect canine health
Please contact Dr. Bannasch via email.
Alexander Borowsky, MD
Center for Comparative Medicine
Dr. Borowsky is a surgical pathologist with expertise in diagnostic breast pathology. His research is focused on development of a mouse model of prostate cancer, focusing on the molecular pathways that are activated or disrupted in various genetically engineered mice, and correlating these findings with the tumor phenotype. Among genes of interest are tumor suppressor genes such as Nes1, which is down regulated by methylation during early breast and prostate cancer. Conditional targeted knockouts of these genes are being developed in mouse models. These findings are being validated and compared with data derived from human tumors, using microarrays, quantitative RNA and laser capture microscopy.
Please visit Dr. Borowsky's website at: http://www.ucdmc.ucdavis.edu/search/faculty/borowsky
Ching-Hsien (Jean) Chen, PhD
SOM: Nephrology/Internal Medicine
(See also: Biochemistry/Cellular Biology, Pulmonary Medicine)
Dr. Chen’s research strives to elucidate the molecular mechanisms underlying cancer malignancy and thereby identify useful biomarkers and/or druggable targets. She seeks to develop peptide-based therapeutics to mitigate cancer metastasis and drug resistance by targeting aberrant oncogenic signaling. Research in her laboratory focuses on how the phospholipids such as PIP2 and PIP3 are regulated during the development of malignancies and inflammatory diseases.
As a STAR Program mentor, I offer projects focused on mechanism-based target identification and drug discovery in smoking-related diseases, including lung cancer and pulmonary fibrosis. Students will investigate disease mechanisms and metabolic dysregulation using techniques such as CRISPR/Cas9, scRNA sequencing, qPCR, and Western blotting. They will characterize the immune microenvironment in cancer and fibrosis using flow cytometry, immunofluorescent staining, and multiplex cytokine assays on tissues from animal models. Additional projects include ex vivo drug screening on patient-derived precision-cut tissue slices and metabolic profiling with mass spectrometry and Seahorse XF Analyzers. Students will gain hands-on experience in molecular biology, immune profiling, cell and tissue culture, and data analysis, contributing to impactful translational research.
Dr. Chen can be reached via email.
Xinbin Chen, BVM, PhD
VM: Veterinary Oncology, Surgical and Radiological Sciences; Med: Internal Medicine
The p53 family proteins are transcription factors and consist of p53, p63, and p73. Each member regulates a diverse array of both common and unique target genes. These target genes mediate various activities for the p53 family proteins, including the cell cycle control, apoptosis, differentiation, senescence, DNA repair, normal development and tumor suppression. p53 is a tumor suppressor and found to be mutated or inactivated in greater than 60% of all human cancers. Mutant p53 is not only defective in tumor suppression but also promotes tumor formation. However, p63 and p73 appear to be necessary for the development of various tissues and immune response. To address these diverse activities for the p53 family proteins, we focus on the following areas of research: (1) to identify both common and unique target genes for each p53 family member and their functions in tumor suppression and development; (2) to determine the mechanism by which the p53 family proteins differentially regulate gene expression; (3) to determine the mechanism by which mutant p53 obtains a gain of function in promoting tumor formation; and (4) to determine the mechanism by which the expression and activity for each p53 family protein is regulated.
Potential Projects for STAR Students:
- The p53 pathway, including p53, p63, p73, Mdm2 and MdmX, in dog osteosarcoma, sarcomas, histocytic sarcomas, and melanoma
- The p53 pathway in cat sarcomas and other cat tumors
Dr. Chen can be reached at xbchen@ucdavis.edu.
Stephanie Goldschmidt, BVM&S, DAVDC
Assistant Professor Dentistry and Oral Surgery
(see also: Dentistry/Oral Biology)
My research interests center on improving the diagnostic and care paradigm for oral cancer. Specifically, I am currently doing work establishing oral cancer cell lines, looking at EGFR expression in oral tumors, and running a clinical trial evaluating the use of fluorescence lifetime imaging to guide intraoperative decision making in oral cancer.
Please email Sgoldschmidt@ucdavis.edu for more information.
Paul Luciw, PhD
Center for Comparative Medicine
Dr. Luciw is a molecular virologist who leads an internationally recognized research program that interdigitates with research programs all over campus. His group has expertise in virology, cell biology, and molecular virology. The main emphasis of his research is on molecular mechanisms that regulate replication and pathogenesis of viruses that establish chronic infections. Additionally, knowledge of virus/host relationships is being used to design and test live-attenuated viral vaccines and to develop novel DNA immunization strategies aimed at preventing viral infection. Dr. Luciw's group focuses on lentivirus models for AIDS, including SIV and SIV/HIV chimeras in macaques, and FIV in cats. As director of viral oncology research on campus, he works on herpesviruses in macaques as models for Kaposi's sarcoma. In addition, he is developing novel multiplex detection methods for serodiagnosis of infectious diseases of mice and non-human primates, analysis of cytokines and chemokines in various disease states in animal models and humans, and studies on cell signaling pathways in cell culture models for cancer.
Please visit Dr. Luciw's website at: paluciw@ucdavis.edu
Robert B. Rebhun, DVM, PhD, DACVIM
VM: Veterinary Oncology, Surgical and Radiological Sciences
Dr. Rebhun is a clinical veterinary oncologist with basic research interests in the biology and therapy of cancer metastasis. The majority of human and veterinary cancer-related deaths result from metastases that are resistant to traditional therapies. Studies aimed at identifying, isolating, and characterizing the specific cells that are capable of forming metastasis may lead to more effective therapies. Tumor initiating cells (sometimes called cancer stem cells) have been shown to possess high metastatic potential in mouse models of human cancer and stem-cell signaling pathways such as hedgehog/Gli/BMI1 signaling have been recently implicated in metastasis and resistance to traditional cytotoxic therapies. My lab is primarily focused on studying molecular factors that drive proliferation and metastasis of osteosarcoma, with specific projects aimed at targeting metastatic osteosarcoma cells within the lung microenvironment.
Please contact Dr. Rebhun at rbrebhun@ucdavis.edu for more information.
Ellen E. Sparger DVM, Ph.D., DACVIM
VM: Department VM Medicine and Epidemiology
Research Interests:
SIV vaccine development using attenuated rhesus CMV vaccine vectors with TLR 5 ligands as adjuvants.
Assessment of antiviral cellular immune responses in the prevention of FIP in cats infected with feline infectious peritonitis coronaviruses.
Assessment of receptor tyrosine kinases (RTK) as targets for cancer therapeutics in feline oral squamous cell carcinoma (OSCC).
Project Appropriate for a Star Student Summer Project:
A feasible project for a Star Student would involve examination of tumor biopsies from clinical cases of feline OSCC for expression and mutation of specific RTKs. This project would include extraction of DNA and/or RNA from tumor tissues followed by PCR amplification of sequences specific to RTKs, including epidermal growth factor receptor (EGFR) and cKit and possibly other RTKs. PCR products would next be sequenced for detection of possible mutations involving activation domains of these proteins. The student involved in this project would perform research in the laboratory of Dr. Sparger but also work with Dr. Katherine Skorupski in the Veterinary Oncology Service to facilitate the collection of biopsies from clinical patients as well as become familiar with this significant cancer entity in cats for which there is no effective therapeutic protocol. Assimilation of clinical data with correlation of RTK expression and sequence will require the student to work closely with both Drs. Sparger and Korupski. Assessment of RTKs in feline OSCC will be critical for determination of which tyrosine kinase inhibitors currently in use for human OSCC, might be effective for feline OSCC as well. This project is part of a larger effort by Drs. Sparger, Korupski, Michael Kent, Boaz Arzi, and Brian Murphy to characterize feline OSCC as a model for human head and neck cancer.
Contact information for Dr. Sparger: e-mail: eesparger@ucdavis.edu
Nissi Varki, M.D.*
Comparative pathology, mouse models of human disease
Affiliated with UC Veterinary Medical Center – San Diego
Director of Histopathology Resources, Cancer and Mouse Histopathology
Professor of Pathology
(See also: Immunology/Infectious Diseases, Cardiology, Pathology/Virology)
Dr. Nissi Varki's research interests include comparative histopathology analysis of genetically altered mice, and models of human diseases including cancer, inflammatory disorders and microbial infections. She is investigating the role of glycosylated molecules in tumor progression and metastasis, including evidence for a human-specific mechanism for diet and antibody-mediated inflammation in human carcinogenesis. Another area of recent exploration is the tissue and species-specific expression of sialic-acid binding lectin receptors known as Siglecs, which play an important role in regulating host innate immune responses and inflammation. Dr. Varki also has a longstanding interest in immunological mechanisms operating at the gastrointestinal mucosal epithelium and their role in chronic colitis and colon cancer development. Dr. Varki serves as Director of the Histopathology Core laboratories Mouse Phenotyping Services at UC San Diego and teaches in the histology and pathology laboratory sessions for medical students, mentors numerous undergraduate students and high school students and serves on the Recruitment and Admissions Committee for the UC San Diego School of Medicine.
Link to Dr. Varki’s current publications
Link to Dr. Varki’s website
*Please contact Peter Ernst pernst@ucsd.edu or Christina Sigurdson csigurdson@ucsd.edu first for more information
Luke A. Wittenburg, DVM, PhD, DACVCP
VM: Surgery & Radiology (See also: Pharmacology/Toxicology, Biochemistry/Cell Biology)
Not taking students in 2025
Dr. Wittenburg is a veterinary clinical pharmacologist with basic research interests in cancer biology and investigational/developmental therapeutics for treatment of cancer in pets and people. A better understanding of the biology and response to therapy in veterinary patients with cancer is crucial to translate discoveries in our pet populations to potential therapies in humans with cancer. Dr. Wittenburg’s current projects involve aspects of clinical pharmacology (PK/PD modeling) and in vitro pharmacology (comparative metabolism of chemotherapeutic drugs across species). Much of our current focus is to study the importance of protein-protein interactions with regard to transcription factors in the development and survival of osteosarcoma. Summer project options include those that are basic science/molecular biology based and involve the use of inhibitors of transcription factor protein-protein interactions in human and canine osteosarcoma as molecular probes for identification of potential novel therapeutic targets, or clinical pharmacology based involving development and implementation of high performance liquid chromatography tandem-mass spectrometry (LC/MS-MS) methods for quantitation of chemotherapeutic drugs in veterinary species.
Please contact Dr. Wittenburg (lwittenburg@ucdavis.edu) for more information.
Kevin D. Woolard, DVM, PhD, Dipl, ACVP
Assistant Professor of Anatomic Pathology
(See also: Neurology/Neurobiology)
The Woolard Laboratory is primarily focused on comparative biology of human and canine glioma brain tumors. These tumors have an aggressive biologic behavior, with median survival times of around 14 months in people, in spite of surgery, chemo-, and radiotherapy. Much of our efforts are focused on identifying how sub-populations within an individual patient’s tumor communicate with each other to establish a dominant population of tumor cells, as well as how cells re-grow following initial treatment. We are also examining how cellular metabolism in glioma may impact epigenetic dysregulation, with the goal of providing a druggable target to delay tumor progression. Finally, we also routinely isolate canine embryonic neural stem cells, which are used as physiologic comparisons to glioma tumor cells. Additionally, we are using these cells to model Zika virus infection in mammalian neural stem cells.
Please contact Dr. Woolard (kdwoolard@ucdavis.edu) for more information.