TY - JOUR
T1 - In vivo melanoma imaging based on dynamic nuclear polarization enhancement in melanin pigment of living mice using in vivo dynamic nuclear polarization magnetic resonance imaging
AU - Hyodo, Fuminori
AU - Naganuma, Tatsuya
AU - Eto, Hinako
AU - Murata, Masaharu
AU - Utsumi, Hideo
AU - Matsuo, Masayuki
N1 - Funding Information:
We thank Ms. Nakaji T, Innovation Center for Medical Redox Navigation, Kyushu University, Japan for helping the melanoma experiments. This work was supported by the Medical Research and Development Programs Focused on Technology Transfer, Development of Advanced Measurement and Analysis Systems (SENTAN) from the Japan Agency for Medical Research and Development (AMED) Grant Number JP18hm0102038s0103 and Special Coordination Funds for Promoting Science and Technology (SCF funding program “Innovation Center for Medical Redox Navigation”) by The Ministry of Education, Culture, Sports, Science and Technology (MEXT). This work was also supported by Japan Society for the Promotion of Science (JSPS) KAKENHI (Grant Number 16H05079 and 16H05113). We thank Edanz Group (www.edanzediting.com/ac) for editing a draft of this manuscript.
Funding Information:
We thank Ms. Nakaji T, Innovation Center for Medical Redox Navigation, Kyushu University, Japan for helping the melanoma experiments. This work was supported by the Medical Research and Development Programs Focused on Technology Transfer, Development of Advanced Measurement and Analysis Systems (SENTAN) from the Japan Agency for Medical Research and Development (AMED) Grant Number JP18hm0102038s0103 and Special Coordination Funds for Promoting Science and Technology (SCF funding program “Innovation Center for Medical Redox Navigation”) by The Ministry of Education, Culture, Sports, Science and Technology (MEXT). This work was also supported by Japan Society for the Promotion of Science (JSPS) KAKENHI (Grant Number 16H05079 and 16H05113). We thank Edanz Group ( www.edanzediting.com/ac ) for editing a draft of this manuscript.
Publisher Copyright:
© 2019 Elsevier Inc.
PY - 2019/4
Y1 - 2019/4
N2 - Melanin is a pigment that includes free radicals and is widely distributed in living animals. Malignant melanoma is one of the most progressive tumors in humans with increasing incidence worldwide, and has shown resistance to chemotherapy, resulting in high mortality at the metastatic stage. In general, melanoma involves the abnormal accumulation of melanin pigment produced by malignant melanocytes. Electron paramagnetic resonance (EPR) spectroscopy and imaging is a powerful technique to directly visualize melanomas using endogenous free radicals in the melanin pigment. Because melanin radicals have a large linewidth, the low spatial resolution of EPR imaging results in blurred images and a lack of anatomical information. Dynamic nuclear polarization (DNP)-MRI is a noninvasive imaging method to obtain the spatio-temporal information of free radicals with MRI anatomical resolution. Proton signals in tissues, including free radicals, can be dramatically enhanced by EPR irradiation at the resonance frequency of the free radical prior to applying the MRI pulse sequence. However, the DNP effects of free radicals in the pigment of living organisms is unclear. Therefore, if endogenous free radicals in melanin pigment could be utilized as a bio-probe for DNP-MRI, this will be an advantage for the specific enhancement of melanoma tissues and might allow the separate noninvasive visualization of melanoma tissues without the need for probe administration. Here, we report that biological melanin pigment induced a in vivo DNP effect by interacting with water molecules. In addition, we demonstrated in vivo melanoma imaging based on the DNP effects of endogenous free radicals in the melanin pigment of living mice.
AB - Melanin is a pigment that includes free radicals and is widely distributed in living animals. Malignant melanoma is one of the most progressive tumors in humans with increasing incidence worldwide, and has shown resistance to chemotherapy, resulting in high mortality at the metastatic stage. In general, melanoma involves the abnormal accumulation of melanin pigment produced by malignant melanocytes. Electron paramagnetic resonance (EPR) spectroscopy and imaging is a powerful technique to directly visualize melanomas using endogenous free radicals in the melanin pigment. Because melanin radicals have a large linewidth, the low spatial resolution of EPR imaging results in blurred images and a lack of anatomical information. Dynamic nuclear polarization (DNP)-MRI is a noninvasive imaging method to obtain the spatio-temporal information of free radicals with MRI anatomical resolution. Proton signals in tissues, including free radicals, can be dramatically enhanced by EPR irradiation at the resonance frequency of the free radical prior to applying the MRI pulse sequence. However, the DNP effects of free radicals in the pigment of living organisms is unclear. Therefore, if endogenous free radicals in melanin pigment could be utilized as a bio-probe for DNP-MRI, this will be an advantage for the specific enhancement of melanoma tissues and might allow the separate noninvasive visualization of melanoma tissues without the need for probe administration. Here, we report that biological melanin pigment induced a in vivo DNP effect by interacting with water molecules. In addition, we demonstrated in vivo melanoma imaging based on the DNP effects of endogenous free radicals in the melanin pigment of living mice.
UR - http://www.scopus.com/inward/record.url?scp=85059643291&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85059643291&partnerID=8YFLogxK
U2 - 10.1016/j.freeradbiomed.2019.01.002
DO - 10.1016/j.freeradbiomed.2019.01.002
M3 - Article
C2 - 30615920
AN - SCOPUS:85059643291
VL - 134
SP - 99
EP - 105
JO - Free Radical Biology and Medicine
JF - Free Radical Biology and Medicine
SN - 0891-5849
ER -