title: Probing early tumor response to radiation therapy using hyperpolarized [1-¹³C]pyruvate in MDA-MB-231 xenografts.
abstract: Following radiation therapy (RT), tumor morphology may remain unchanged for days and sometimes weeks, rendering anatomical imaging methods inadequate for early detection of therapeutic response. Changes in the hyperpolarized [1-¹³C]lactate signals observed in vivo following injection of pre-polarized [1-¹³C]pyruvate has recently been shown to be a marker for tumor progression or early treatment response. In this study, the feasibility of using ¹³C metabolic imaging with [1-¹³C]pyruvate to detect early radiation treatment response in a breast cancer xenograft model was demonstrated in vivo and in vitro. Significant decreases in hyperpolarized [1-¹³C]lactate relative to [1-¹³C]pyruvate were observed in MDA-MB-231 tumors 96 hrs following a single dose of ionizing radiation. Histopathologic data from the treated tumors showed higher cellular apoptosis and senescence; and changes in the expression of membrane monocarboxylate transporters and lactate dehydrogenase B were also observed. Hyperpolarized ¹³C metabolic imaging may be a promising new tool to develop novel and adaptive therapeutic regimens for patients undergoing RT.
authors: GE Healthcare, Toronto, Canada. Albert.Chen@ge.com
authors: Albert P
authors: AP
authors: Chen
authors: William
authors: W
authors: Chu
authors: Yi-Ping
authors: YP
authors: Gu
authors: Charles H
authors: CH
authors: Cunningham
authors: Charles H
authors: CH
authors: Cunnhingham
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000528:radiation effects; D001943:Breast Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology* / Q000532:radiotherapy*; D002250:Carbon Radioisotopes; D045744:Cell Line, Tumor; D002471:Cell Transformation, Neoplastic; D016922:Cellular Senescence / Q000528:radiation effects; D006801:Humans; D008297:Male; D019289:Pyruvic Acid; D051381:Rats; D011923:Rats, Nude; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D002250:Carbon Radioisotopes; D019289:Pyruvic Acid