Xiaowei (George) Xu, MD, PhD

Professor of Pathology and Laboratory Medicine at the
Hospital of the University of Pennsylvania
Professor of Pathology and Laboratory Medicine in Dermatology
Perelman School of Medicine at the University of Pennsylvania

Associate Vice Chair for Research
Department of Pathology and Laboratory Medicine

Contact InformationHospital of the University of Pennsylvania
Department of Pathology and Laboratory Medicine
6 Founders Pavilion
3400 Spruce Street
Philadelphia, PA 19104
Tel: 215-662-6503
Fax: 215-349-5910

Specialty Division

Anatomic Pathology, Cancer and Immunobiology

Research Expertise

Develop gamma delta T cell and extracellular vesicle-based immunotherapies for melanoma and other skin conditions

Clinical Expertise

Dermatopathology, pigmented lesions and vasculitis

Itmat Expertise

Dr. Xu’s lab is dedicated to develop immunotherapies using gamma delta T cells and extracellular vesicles to treat melanoma and other skin conditions.

Rotation Projects Expertise

1. Define molecular mechanisms of human gamma delta T cell exhaustion
2. Enhance engineered gamma delta T cell functions in the tumor microenvironment
3. Develop engineered extracellular vesicles to to treat cancer
4. Develop extracellular vesicle-based biomarkers to predict immunotherapy treatment response

Research details Expertise

1. Develop gamma delta T cell-based therapies for melanoma. We engineer human gamma delta T cells with chimeric antigen receptors or use different cytokines to enhance their tumor-homing and killing functions.
2. Develop extracellular vesicle-based therapies for melanoma and other cancers. We engineer extracellular vesicles from natural killer cells or gamma delta T cells to enhance their tumor-homing and killing functions.
3. Develop extracellular vesicle-based biomarkers that may be used to monitor tumor progression and predict the treatment response to checkpoint inhibitors

Keywords Expertise

Therapeutics, extracellular vesicles, gamma delta T cells, skin, melanoma


MD (Medicine), Fudan University School of Medicine, Shanghai, China, 1992
PhD (Pharmacology), Wake Forest University School of Medicine, Winston-Salem, NC, 1996

Specialty Certification

American Board of Pathology (Anatomic and Clinical Pathology), 2001
American Board of Pathology and Dermatology (Dermatopathology), 2002

Postgraduate Training

Postdoctoral Fellowship, Department of Physiology and Pharmacology, Dr. William Sonntag's Lab, Wake Forest University, Winston Salem, NC, 1996-1997
Resident in Anatomic and Clinical Pathology, Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA, 1997-2001
Postdoctoral Fellowship, Department of Dermatology, Dr. George Cotsarelis' Lab, University of Pennsylvania, Philadelphia, PA, 1999-2001
Clinical Fellowship in Dermatopathology, Harvard Medical School, Boston, MA, 2001-2002

Awards and Honors

Scholarship from Shanghai Medical, Shanghai China University Youth Research Funds, 1988-1990
Glenn Foundation Scholar Award from The American Federation For Aging Research., 1994-1994
Glenn Foundation Endocrinology and Aging Award, 1997-1997
Travel grant from American Association for Cancer Research, Inc., 1998
Warren R. Lang award for resident physician best scientific paper from American Society of Cytopathology, 2000
Stowell-Orbison award for resident physician best scientific paper from United States and Canadian Academy of Pathology, 2002
McCabe fellowship, University of Pennsylvania, 2003
America's Top Doctors, 2017
Top Doctors 2018, Philadelphia magazine, 2018
Top Doctors 2019, Philadelphia magazine, 2019
Clinical Research 2019 Top Ten Finalists by Clinical Research Forum, 2019
Highly Cited Researcher, Web of Science, Clarivate, 2020
Distinguished Pathologist Award, Chinese American Pathologists Association, 2020
Top Doctors 2020, Philadelphia magazine, 2020
Highly Cited Researcher, Web of Science, Clarivate, 2021
Top Doctors 2021, Philadelphia magazine, 2021
Highly Cited Researcher, Web of Science, Clarivate, 2022
Top Doctors 2022, Philadelphia magazine, 2022
Highly Cited Researcher, Web of Science, Clarivate, 2023
Top Doctors 2023, Philadelphia magazine, 2023

Memberships and Professional Organizations

Society for Melanoma Research, 2004 - 2014
American Cancer Society, 2004 - 2006
International Society of Stem Cell Research, 2004 - 2006
American Society of Investigative Pathology, 2006 - 2010
Chinese National Science Foundation, 2007 - 2013
Plexxicon, 2007 - 2009
United States and Canadian Academy of Pathology, 2007 - 2012
NIH study section, ZRG1 VH-E 10, 2009 - 2009
Hoffmann-La Roche Inc, 2009 - 2009
VA Merit award review, RRD0 R, 2009 - 2009
NIH study section (ZRG1 VH-F 02), 2010 - 2010
VA Merit award review, RRD0 R, 2010 - 2010
Scottish Chief Scientist Office, 2010 - 2015
Scientific Merit Review Board, Department of Veterans Affairs Rehabilitation Research and Development Service., 2010 - 2014
Melanoma Research Foundation, 2012 - Present
NIH study section (RPRB-B (O1)), 2014 - 2014
NIH Study section, special emphasis panel (SEP-9), 2014 - 2014
NCI study section, 2016/01 ZCA1 RPRB-B (J1) P, 2015 - 2015
The North American Chinese Dermatologist Association, 2015 - 2019
NCI review, Targeted Radionuclide Therapy, 2015 - 2015
Chinese National Natural Science Foundation of China, 2016 - 2019
NIH study section, ZCA1 SRB-J (M4), 2017 - 2017
Chinese National Science Foundation of China, 2017 - 2019
NCI SPORE III Review Committee, 2018 - 2018
NCI Study Section (ZCA1 TCRB-3 C1 B, TEP-1A), 2019 - 2019
NIH 2021 ZRG1 OTC1-J (55), 2021 - 2021
NIH study section, 2022/10 ZCA1 SRB-P (O1) S, 2022 - 2022
NIH study section, ZRG1 CTH-B (55) R, 2022 - 2022
NIH study section, MCTC, Mechanisms of Cancer Therapeutics C Study Section, 2023 - 2023
2024/10 NCI-I R, Transition to Independence Study Section, 2024 - 2024
NIH study section, NCI Clinical and Translational Cancer Research, 2024/10 ZCA1 RPRB-L (O1) R, 2024 - 2024

Selected Publications

Stromal changes in the aged lung induce an emergence from melanoma dormancy

Fane ME, Chhabra Y, Alicea GM, Maranto DA, Douglass SM, Webster MR, Rebecca VW, Marino GE, Almeida F, Ecker BL, Zabransky DJ, Hüser L, Beer T, Tang HY, Kossenkov A, Herlyn M, Speicher DW, Xu W, Xu X, Jaffee EM, Aguirre-Ghiso JA, Weeraratna AT., Nature 606(7913): 396-405, 2022

Exosomal PD-L1 Mediates Tumor Immunosuppression and is Associated with Patient Response to anti-PD-1 Immunotherapy

Chen G, Huang AC, Zhang W, Zhang G, Wu M, Xu W, Yu Z, Yang J, Wang B, Sun H, Xia H, Man Q, Zhong W, Antelo LF, Wu B, Xiong X, Liu X, Guan L, Li T, Liu S, Yang R, Lu Y, Dong L, McGettigan S, Somasundaram R,Radhakrishnan R, Mills G, Lu Y, Kim J, Chen YH, Dong H, Zhao Y, Karakousis GC, Gangadhar TC, Schuchter LM, Herlyn M, Wherry EJ, Xu X,* Guo W*. * indicates co-corresponding authors, Nature 560(7718): 382-386, 2018

PAK Signaling Drives Acquired Drug Resistance to MAPK Inhibitors in BRAFmutant Melanomas.

Lu H, Liu S, Zhang G, Bin Wu, Zhu Y, Frederick DT, Hu Y, Zhong W, Randell S, Sadek N, Zhang W, Chen G, Cheng C, Zeng J, Wu LW, Zhang J, Liu X, Xu W, Krepler C, Sproesser K, Xiao M, Miao B, Liu J, Song CD, Liu JY, Karakousis GC, Schuchter LM, Lu Y, Mills G, Cong Y, Chernoff J, Guo J, Boland GM, Sullivan RJ, Wei Z, Field J, Amaravadi RK, Flaherty KT, Herlyn M*, Xu X*, Guo W*. *Herlyn, Xu and Guo are co-corresponding authors., Nature 550(7674): 133-136, 2017

Costimulation of γδTCR and TLR7/8 promotes Vδ2 T-cell antitumor activity by modulating mTOR pathway and APC function.

Wang H, Chen H, Liu S, Zhang J, Lu H, Somasundaram R, Choi R, Zhang G, Ou L, Scholler J, Tian S, Dong L, Yeye G, Huang L, Connelly T, Li L, Huang A, Mitchell TC, Fan Y, June CH, Mills GB, Guo W, Herlyn M, Xu X., J Immunother Cancer. 9(12): e003339, 2021

Dichotomous and stable gamma delta T-cell number and function in healthy individuals.

Ou L, Wang H, Liu Q, Zhang J, Lu H, Luo L, Shi C, Lin S, Dong L, Guo Y, Huang L, Zhu J, Yin X, Huang AC, Karakousis G, Schuchter L, Amaravadi R, Zheng C, Fan Y, Guo W, Xu X., J Immunother Cancer 9(5): e002274, 2021

Pathological response and survival with neoadjuvant therapy in melanoma: a pooled analysis from the International Neoadjuvant Melanoma Consortium (INMC)

Menzies AM, Amaria RN, Rozeman EA, Huang AC, Tetzlaff MT, van de Wiel BA, Lo S, Tarhini AA, Burton EM, Pennington TE, Saw RPM, Xu X, Karakousis GC, Ascierto PA, Spillane AJ, van Akkooi ACJ, Davies MA, Mitchell TC, Tawbi HA, Scolyer RA, Wargo JA, Blank CU, Long GV., Nat Med 27(2): 301-309, 2021, PMID:33558722

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Loss of Phd2 Cooperates with BRAFV600E to Drive Melanomagenesis

Liu S, Zhang G, Guo J, Chen X, Lei J, Ze K, Dong L, Dai X, Song D, Ecker B, Yang R, Feltcher C, Peng K, Feng C, Chen H, Lee RX, Kerestes H, Niu J, Kumar S, Xu W, Zhang J, Wei Z, Martin JS, Liu X, Mills G, Lu Y, Guo W, Weeraratna A, Herlyn M, Wei W, Lee FS, Xu X, Nat Commun. 9(1): 5426, 2018

A single dose of neoadjuvant PD-1 blockade predicts clinical outcomes in resectable melanoma.

Huang AC, Orlowski RJ, Xu X, Mick R, George SM, Yan PK, Manne S, Kraya AA, Wubbenhorst B, Dorfman L, D'Andrea K, Wenz BM, Liu S, Chilukuri L, Kozlov A, Carberry M, Giles L, Kier MW, Quagliarello F, McGettigan S, Kreider K, Annamalai L, Zhao Q, Mogg R, Xu W, Blumenschein WM, Yearley JH, Linette GP, Amaravadi RK, Schuchter LM, Herati RS, Bengsch B, Nathanson KL, Farwell MD, Karakousis GC, Wherry EJ, Mitchell TC., Nat Med. 25(3): 454-61, 2019

TOX transcriptionally and epigenetically programs CD8+ T cell exhaustion

Khan O, Giles JR, McDonald S, Manne S, Ngiow SF, Patel KP, Werner MT, Huang AC, Alexander KA, Wu JE, Attanasio J, Yan P, George SM, Bengsch B, Staupe RP, Donahue G, Xu W, Amaravadi RK, Xu X, Karakousis GC, Mitchell TC, Schuchter LM, Kaye J, Berger SL, Wherry EJ, Nature 571(7764): 211-218, 2019

Clinical efficacy of a RAF inhibitor requires comprehensive ERK pathway inhibition in BRAF-mutant melanoma

Bollag G, Hirth P, Tsai J, Zhang J, Ibrahim PN, Cho H, Spevak W, Zhang C, Zhang Y, Habets G, Burton B, West BL, Powell B, Shellooe R, Marimuthu A, Nguyen H, Zhang KYJ, Artis DR, Schlessinger J, Su F, Higgins B, Iyer R, D’Andrea K, Koehler A, Stumm M, Lee RJ, Grippo J, Puzanov I, Kim KB, Ribas A, McArthur GA, Sosman JA, Chapman PB, Flaherty KT, Xu X, Nathanson KL, Nolop K, Nature 467(7315): 596-9, 2010