Dr. Brownell is a board-certified dermatologist and a fellow of the American Academy of Dermatology. He directs a research program that includes basic, translational, and clinical investigations of skin homeostasis and skin cancer. Dr. Brownell is an attending physician on the NIH Clinical Center’s Dermatology Consultation Service and he co-directs the Cutaneous Oncology Program at the Murtha Cancer Center, Walter Reed National Military Medical Center. He is also an Adjunct Investigator at the National Cancer Institute (NCI).

Research Statement

Dr. Brownell studies the regulation of cutaneous stem cells and the molecular pathogenesis of skin cancer. A current research focus is the biology of neuroendocrine Merkel cells and the oncogenesis of Merkel cell carcinoma. Using mouse genetics, Dr. Brownell investigates the signals that regulate skin stem cell development and maintenance. Mouse models are also used to study targets identified by high-throughput oncogenomic analysis of human skin tumors. In complementary studies, high-throughput screening techniques are used to identify novel therapeutic targets and treatments for skin cancers. In collaboration with oncologists in the National Cancer Institute, Dr. Brownell conducts early phase clinical trials treating skin cancer.

Scientific Publications

Hedgehog Signaling Inhibitors Fail to Reduce Merkel Cell Carcinoma Viability.

Carroll TM, Williams JS, Daily K, Rogers T, Gelb T, Coxon A, Wang SQ, Crago AM, Busam KJ, Brownell I
The Journal of investigative dermatology.
2017 May;
doi: 10.1016/j.jid.2017.01.008
PMID: 28130073

Avelumab in patients with chemotherapy-refractory metastatic Merkel cell carcinoma: a multicentre, single-group, open-label, phase 2 trial.

Kaufman HL, Russell J, Hamid O, Bhatia S, Terheyden P, D'Angelo SP, Shih KC, Lebbé C, Linette GP, Milella M, Brownell I, Lewis KD, Lorch JH, Chin K, Mahnke L, von Heydebreck A, Cuillerot JM, Nghiem P
The Lancet. Oncology.
2016 Oct;
doi: 10.1016/S1470-2045(16)30364-3
PMID: 27592805

A Cascade of Wnt, Eda, and Shh Signaling Is Essential for Touch Dome Merkel Cell Development.

Xiao Y, Thoresen DT, Miao L, Williams JS, Wang C, Atit RP, Wong SY, Brownell I
PLoS genetics.
2016 Jul;
doi: 10.1371/journal.pgen.1006150
PMID: 27414798

Evaluating blood levels of neuron specific enolase, chromogranin A, and circulating tumor cells as Merkel cell carcinoma biomarkers.

Gaiser MR, Daily K, Hoffmann J, Brune M, Enk A, Brownell I
2015 Sep 22;
doi: 10.18632/oncotarget.4500
PMID: 26299616

Neural Hedgehog signaling maintains stem cell renewal in the sensory touch dome epithelium.

Xiao Y, Thoresen DT, Williams JS, Wang C, Perna J, Petrova R, Brownell I
Proceedings of the National Academy of Sciences of the United States of America.
2015 Jun 9;
doi: 10.1073/pnas.1504177112
PMID: 26015562

Nerve-derived sonic hedgehog defines a niche for hair follicle stem cells capable of becoming epidermal stem cells.

Brownell I, Guevara E, Bai CB, Loomis CA, Joyner AL
Cell stem cell.
2011 May 6;
doi: 10.1016/j.stem.2011.02.021
PMID: 21549329


Baylor College of Medicine, Houston, TX

University of Maryland, College Park
B.S., Electrical Engineering and Mathematics


After graduating from the Medical Scientist Training Program at Baylor College of Medicine, Dr. Brownell completed an internship at Christus St. Joseph Hospital in Houston, TX and a Dermatology residency at the New York University School of Medicine. Dr. Brownell completed a postdoctoral research fellowship on Hedgehog signaling and cutaneous stem cells in the lab of Dr. Alexandra Joyner at Memorial Sloan-Kettering Cancer Center where he was also a clinical faculty member on the Dermatology Service. His clinical practice focused on patients with high-risk skin cancers. In 2011 Dr. Brownell joined the Dermatology Branch in the Center for Cancer Research, National Cancer Institute. In 2017 Dr. Brownell and the Dermatology Branch transferred to the National Institute of Arthritis and Musculoskeletal and Skin Diseases where he is currently a tenure-track investigator and Head of the Cutaneous Development and Carcinogenesis Section. Dr. Brownell is also an Adjunct Assistant Professor of Dermatology in the School of Medicine, Uniformed Services University of the Health Sciences, and he co-directs the Cutaneous Oncology Program, Murtha Cancer Center, Walter Reed National Military Medical Center.

Last Updated: June 2020