Carroll Lab

Laboratory Members

Professor, Department of Pathology & Laboratory Medicine

Director, Hollings Cancer Center Biorepository & Tissue Analysis Shared Resource

Director, Carroll A. Campbell Jr. Neuropathology Laboratory (Brain Bank)

Gordon R Hennigar Jr., M.D. Endowed Chair in Pathology

System Chief, Pathology & Lab Medicine Integrated
Center of Clinical Excellence

About Dr. Steven Carroll

Dr. Steven Carroll is a professor in the Department of Pathology and Laboratory Medicine at the Medical University of South Carolina (MUSC), where he holds the Gordon R. Hennigar, Jr., MD, Endowed Chair in Pathology. Dr. Carroll also serves as the System Chief of the MUSC Pathology and Laboratory Medicine Integrated Center of Clinical Excellence (ICCE), the Director of the Carroll A. Campbell Jr. Neuropathology Laboratory (Brain Bank) and the Director of the Hollings Cancer Center Biorepository & Tissue Analysis Shared Resource. Dr. Carroll is a practicing neuropathologist certified by the American Board of Pathology in Anatomic Pathology and Neuropathology. Dr. Carroll has over 25 years of experience as a molecular neurobiologist using human tissues, genetically engineered mouse models and genomic analyses to investigate the molecular basis of diseases of the human nervous system. Dr. Carroll is an Associate Editor for the American Journal of Pathology and the Journal of Neuropathology and Experimental Neurology and serves on the Editorial Board of Neuro-Oncology. Dr. Carroll, in partnership with the Children's Tumor Foundation, has established a national network that collects and banks tissues from patients with neurofibromatosis type a (NF1), NF2 or schwannomatosis. Dr. Carroll is also a founding member of the Down Syndrome Biobank Consortium, an international consortium that banks brain tissue and other biospecimens from patients that have Down syndrome-associated Alzheimer’s disease.

Dr. Carroll received his B.S. degree with majors in vertebrate zoology, chemistry and archeology from the University of Memphis in 1981. He then attended Baylor College of Medicine, receiving his Ph.D. in Cell Biology in 1986 and his M.D. in 1988. Dr. Carroll's dissertation research was performed in the laboratory of Dr. Robert Schwartz and focused on the structure and genetic regulation of the chicken α-smooth muscle actin gene, which is essential for vascular function. Dr. Carroll's Anatomic Pathology Residency and Neuropathology Fellowship were performed at the Washington University School of Medicine (1988-1994). Dr. Carroll also completed his postdoctoral research fellowship in the laboratory of Dr. Jeffrey Milbrandt before joining the faculty of the Washington University School of Medicine. Prior to his arrival at MUSC, Dr. Carroll was Professor of Pathology, Neurobiology and Cell Biology at the University of Alabama at Birmingham (UAB) and the Director of the UAB Division of Neuropathology. While at UAB, Dr. Carroll served as an attending neuropathologist at the University of Alabama Hospital, the Birmingham VA, UAB Highlands Hospital and Alabama Children's Hospital. He was a Scientist in the UAB Alzheimer's Disease Research Center, the Mental Retardation Research Center, the Center for Aging, the Center for Glial Biology in Medicine, the Civitan International Research Center and the Center for Neurodegeneration and Experimental Therapeutics as well as being as a Member of the Comprehensive Neuroscience Center and a Senior Scientist in the UAB Comprehensive Cancer Center.

Dr. Carroll and his wife Pam have two daughters, Heather and Kristen, and three granddaughters, Charlotte, Sophia and Alice. They share their home with three furballs: Sarge, who is an American foxhound, Ringo the basset hound and their cat, Mr. Bosley. Dr. Carroll is an amateur paleontologist although, sadly, he doesn't get many opportunities to fossil hunt these days.

Dr. Carroll's granddaughters: Sophia, Charlotte, and Alice

Dr. Carroll's granddaughters: Sophia, Charlotte, and Alice.

Dr. Carroll's dog, Sarge.

Dr. Carroll's dog, Ringo

Dr. Carroll's dog, Ringo.

Jody Longo, Ph.D.

Assistant Professor, Department of Pathology & Laboratory Medicine

About Dr. Jody Longo

Dr. Jody Fromm Longo is an Assistant Professor in the Department of Pathology and Laboratory Medicine within the School of Medicine at the Medical University of South Carolina (MUSC).

Dr. Fromm Longo received her bachelor's degree in chemistry/biochemistry from Purdue University in West Lafayette, IN in 1994. She worked with Dr. Arnold Stein for her undergraduate research project on the development of miniaturized DNA sequencing gels for rapid Sangar sequencing. She obtained her Ph.D. in molecular biology and biochemistry from the University of Southern California (USC), Los Angeles, CA in 2007. There she studied oncogenic EGFR activation of Ras-mediated transcriptional regulatory mechanisms in glioblastoma-multiforme tumors (GBM) under Dr. Deborah L. Johnson.

She performed her postdoctoral training in cancer biology and genetics with Karen Cichowski at Harvard Medical School and Brigham and Women's Hospital in Boston, MA. There she studied hyperactive Ras signaling mediated by loss of a RasGAP tumor suppressor called neurofibromin in GBM tumors and in patients with the disease Neurofibromatosis Type 1 (NF1) afflicted with malignant peripheral nerve sheath tumors (MPNSTs). Her focus was on signal transduction and preclinical drug studies for these Ras-driven tumor types.

She relocated to Charleston, SC and joined the Medical University of South Carolina in 2014 as a Staff Scientist in the Department of Pathology and Laboratory Medicine with Dr. Steven Carroll. Her research focus at MUSC has continued to be focused on therapeutic development for MPNSTs, a Schwann cell derived Ras-driven tumor type. Her research endeavors are centered around therapeutically targeting Ras-driven tumors mediated by aberrant upstream activation of EGFR or erbB receptors or loss of the tumor suppressor neurofibromin (negative regulator of Ras). Her approaches include bioinformatic assessment of the transcriptome and mutational profile of human tumors and cell lines as well as validation studies using cell-based assays and animal models.

In September 2020, she joined the Department of Pathology and Laboratory Medicine faculty as a Research Assistant Professor. Her current research focus is centered around bioinformatics and novel roles of neurofibromin outside of its RasGAP activity in Schwann cells.

Research Interests

The Carroll laboratory focuses on identifying the abnormalities that promote the pathogenesis of cancer and neurodegenerative diseases and using this information to develop effective new therapies. We have a particular interest in the role that the growth factor neuregulin-1 (NRG1) and its erbB receptors play in the development of these diseases.

Cancer Biology

Our work in cancer biology is directed towards determining how neurofibromas and malignant peripheral nerve sheath tumors (MPNSTs) develop in patients with the multi-system genetic disease neurofibromatosis type 1 (NF1) with therapeutic development being the end goal. We are pursuing a two-pronged approach to achieve this goal. In our first approach, we are using our understanding of the natural history of neurofibromas and MPNSTs to guide us to existing agents that are potentially effective against these tumors. For instance, since aberrant Ras signaling is characteristic of these tumors, we have used phosphoproteomics and other approaches to identify potential druggable targets within the pathways downstream of NF1-regulated Ras proteins as well as upstream activators of Ras in neurofibromas and MPNSTs. This latter group includes receptors for the growth factor neuregulin-1 (NRG1), which led us to create mice in which we can genetically ablate these receptors and examine the effect this has on MPNST pathogenesis. Our second, longer term approach is to identify novel therapeutic targets by comprehensively defining the genomic and epigenetic abnormalities that mediate the pathogenesis of plexiform neurofibromas and MPNSTs. To achieve this, we are using cross-species comparative oncogenomics, a method in which driver mutations are first identified in a mouse cancer model and then validated in human tumors. For these studies, we have created several genetically engineered mouse models which recapitulate the process of neurofibroma-MPNST progression seen in humans. We have performed comprehensive genomic analyses (array comparative genomic hybridization, high density SNP array analyses, whole exome sequencing and whole transcriptome sequencing) of MPNSTs from these mice, together with a reference set of human MPNST tumors and cell lines, to identify the driver mutations responsible for tumor development. We have partnered these genomic analyses with functional (genome-scale shRNA) screens to identify gene products that are essential for proliferation and survival.

Ongoing work is directed towards performing preclinical trials with mouse models to test the effectiveness of drugs that target these gene products.

Our work in neurobiology focuses on Alzheimer’s disease, frontotemporal dementias and amyotrophic lateral sclerosis (ALS). Our laboratory was the first to show that NRG1, a protein that plays an important role in synaptogenesis, and its receptors are aberrantly distributed in neuritic plaques in humans with Alzheimer’s disease and genetically engineered mouse models of Alzheimer’s disease. After globally identifying the cellular populations expressing erbB receptors in the adult rat brain with immunohistochemistry and in situ hybridization, we additionally showed that NRG1 plays an important role in shaping the dendritic and axonal trees of hippocampal neurons and that this growth factor is an important survival factor for motor neurons in the spinal cord. At present, we are constructing several new genetically engineered mouse models to assess the role that specific erbB mutations play in the pathogenesis of frontotemporal dementias and ALS and to ascertain whether NRG1 can be used to slow the development of Alzheimer’s disease and other dementias.

As with our cancer work, we partner mouse and cell culture models of neurodegenerative diseases with studies of brain tissue and other biospecimens collected from patients with dementia. These studies are facilitated by the fact that Dr. Carroll is the Director of the Carroll A. Campbell, Jr. Neuropathology Laboratory, which contains a collection of several hundred brains from patients with Alzheimer’s and related dementias that have been donated for research. In collaboration with Drs. Eric Hamlett, Brad Schulte and Judy Dubno, we are using these specimens to determine whether pathologic changes affecting the brain circuitry responsible for hearing and other senses occurs in Alzheimer’s disease and whether clinical changes in these senses can be used as a biomarker for diagnosing the early stages of Alzheimer’s disease. The Carroll A. Campbell, Jr. Neuropathology Laboratory is also a founding member of an international consortium of brain banks that collect brain tissue and other research specimens from Down syndrome patients, who almost inevitably develop Alzheimer’s disease in their forties. In collaboration with Dr. Eric Hamlett and Lotta Granholm, we have used specimens from these patients to establish that changes in the protein cargo contained in neuronally-derived exosomes can be used as a biomarker for the early stages in the development of Alzheimer’s disease.

In addition to these research areas, Dr. Carroll is the Director of the Hollings Cancer Center Biorepository and Tissue Analysis Shared Resource. In this role, Dr. Carroll participates in the Human Cooperative Tissue Network, a multi-institution network that banks and distributes tumor tissue for research to investigators across the United States and elsewhere. The Biorepository is also an active participant in an effort headed by Dr. Marvella Ford that partners MUSC with South Carolina State University; this project focuses on understanding the basis for disparate outcomes in cancer patients from diverse backgrounds.