Xin Cai M.D. Ph.D is an Assistant Professor and Physician-Scientist in the Department of Radiation Oncology.  His lab studies cancer metabolism and signal tranduction.

Xin earned both his B.A. and M.A. degrees from Harvard University majoring in Chemistry and Physics, followed by the M.D./Ph.D. training at UT Southwestern Medical Center through the Medical Scientist Training Program.  He completed his Radiation Oncology residency at Memorial Sloan Kettering Cancer Center, where he also completed a postdoc fellowship studying cancer metabolism.  Xin has earned many awards and honors, including the HHMI Predoctoral Fellowship, ABR Holman Research Pathway Fellow, and NIH/NCI K99/R00 Pathway to Independence Award.

Xin returned to UTSW as faculty in 2023.  In addition to being the principal investigator of the Cai Lab, he also sees patients as part of the central nervous system (CNS) disease-oriented team in the Radiation Oncology clinic. 


Postdoctoral Fellowship
Memorial Sloan Kettering Cancer Center 2021, Radiation Oncology
Graduate School
Harvard University (2009), Chemistry
Medical School
UT Southwestern Medical School (2016)
Memorial Sloan Kettering Cancer Center (2017), Radiation Oncology
Memorial Sloan Kettering Cancer Center (2021), Radiation Oncology

Research Interest

  • Metabolism, signal transduction, mitochondria function, cell growth and proliferation, cancer


Lactate activates the mitochondrial electron transport chain independently of its metabolism
Cai X, Ng CP, Jones O, Fung TS, Ryu KW, Li D, Thompson CB Molecular cell 2023 Nov 83 3904-3920.e7
A tissue injury sensing and repair pathway distinct from host pathogen defense
Liu S, Hur YH, Cai X, Cong Q, Yang Y, Xu C, Bilate AM, Gonzales KA, Parigi SM, Cowley CJ, Hurwitz B, Luo JD, Tseng T, Gur-Cohen S, Sribour M, Omelchenko T, Levorse J, Pasolli HA, Thompson CB, Mucida D, Fuchs E Cell 2023 May 186 2127-2143.e22
Fibroblast pyruvate carboxylase is required for collagen production in the tumour microenvironment
Schwörer S, Pavlova NN, Cimino FV, King B, Cai X, Sizemore GM, Thompson CB Nature Metabolism 2021 Nov 3 1484-1499
Prion-like polymerization in immunity and inflammation
Cai X, Xu H, Chen ZJ Cold Spring Harbor Perspectives in Biology 2017 Apr 9
Phosphorylation of innate immune adaptor proteins MAVS, STING, and TRIF induces IRF3 activation
Liu S, Cai X, Wu J, Cong Q, Chen X, Li T, Du F, Ren J, Wu YT, Grishin NV, Chen ZJ Science 2015 Mar 347
TLR3 deficiency in herpes simplex encephalitis: High allelic heterogeneity and recurrence risk
Lim HK, Seppänen M, Hautala T, Ciancanelli MJ, Itan Y, Lafaille FG, Dell W, Lorenzo L, Byun M, Pauwels E, Rönnelid Y, Cai X, Boucherit S, Jouanguy E, Paetau A, Lebon P, Rozenberg F, Tardieu M, Abel L, Yildiran A, Vergison A, Roivainen R, Etzioni A, Tienari PJ, Casanova JL, Zhang SY Neurology 2014 Nov 83 1888-1897
Incomplete specialty referral among children in community health centers
Zuckerman KE, Cai X, Perrin JM, Donelan K Journal of Pediatrics 2011 Jan 158 24-30
Enzymatic primer-extension with glycerol-nucleoside triphosphates on DNA templates
Chen JJ, Tsai CH, Cai X, Horhota AT, McLaughlin LW, Szostak JW PloS one 2009 Mar 4
N2′→ P3′ phosphoramidate glycerol nucleic acid as a potential alternative genetic system
Chen JJ, Cai X, Szostak JW Journal of the American Chemical Society 2009 Feb 131 2119-2121

Honors & Awards

  • ABR Holman Research Pathway Fellow
  • Howard Hughes Medical Institute (HHMI) Predoctoral Fellowship
  • NIH/NCI K99/R00 Pathway to Early Independence Award

Professional Associations/Affiliations

  • American Society for Radiation Oncology (ASTRO) (2016)
  • New York Academy of Sciences (NYAS) (2016)
  • Radiological Society of North America (RSNA) (2016)