In:
Cancer Research, American Association for Cancer Research (AACR), Vol. 73, No. 11 ( 2013-06-01), p. 3216-3224
Abstract:
For tumor radiotherapy, the in vivo detection of early cellular responses is important for predicting therapeutic efficacy. Mn2+ is used as a positive contrast agent in manganese-enhanced MRI (MEMRI) and is expected to behave as a mimic of Ca2+ in many biologic systems. We conducted in vitro and in vivo MRI experiments with Mn2+ to investigate whether MEMRI can be used to detect cell alterations as an early-phase tumor response after radiotherapy. Colon-26 cells or a subcutaneously grafted colon-26 tumor model were irradiated with 20 Gy of X-rays. One day after irradiation, a significant augmentation of G2–M-phase cells, indicating a cell-cycle arrest, was observed in the irradiated cells in comparison with the control cells, although both early and late apoptotic alterations were rarely observed. The MEMRI signal in radiation-exposed tumor cells (R1: 0.77 ± 0.01 s−1) was significantly lower than that in control cells (R1: 0.82 ± 0.01 s−1) in vitro. MEMRI signal reduction was also observed in the in vivo tumor model 24 hours after irradiation (R1 of radiation: 0.97 ± 0.02 s−1, control: 1.10 ± 0.02 s−1), along with cell-cycle and proliferation alterations identified with immunostaining (cyclin D1 and Ki-67). Therefore, MEMRI after tumor radiotherapy was successfully used to detect cell alterations as an early-phase cellular response in vitro and in vivo. Cancer Res; 73(11); 3216–24. ©2013 AACR.
Type of Medium:
Online Resource
ISSN:
0008-5472
,
1538-7445
DOI:
10.1158/0008-5472.CAN-12-3837
Language:
English
Publisher:
American Association for Cancer Research (AACR)
Publication Date:
2013
detail.hit.zdb_id:
2036785-5
detail.hit.zdb_id:
1432-1
detail.hit.zdb_id:
410466-3
Permalink
