Extracellular pH is a biomarker enabling detection of breast cancer and liver cancer using CEST MRI.

Abstract

Extracellular pH (pHe) decrease is associated with tumor growth, invasion, metastasis, and chemoresistance, which can be detected by chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI). Here, we demonstrated that ioversol CEST MRI can be exploited to achieve pHe mapping of the liver cancer microenvironment. In in vitro studies, we firstly explored whether ioversol signal is pH-dependent, and calculated the function equation between the CEST effects of ioversol and pH values, in the range of 6.0 to 7.8, by a ratiometric method. Then we verified the feasibility of this technique and the equation in vivo by applying pHe imaging in an MMTV-Erbb2 transgenic mouse breast cancer model, which is often used in CEST pHe studies. Furthermore, in vivo ioversol CEST MRI, we were able to map relative pHe and differentiate between tumor and normal tissue in a McA-RH7777 rat hepatoma model. This suggests pHe may be a useful biomarker for human liver cancer.

• Authors: Miaomiao Chen, Chaoying Chen, Zhiwei Shen, Xiaolei Zhang, Yanzi Chen, Fengfeng Lin, Xilun Ma, Caiyu Zhuang, Yifei Mao, Haochuan Gan, Peidong Chen, Xiaodan Zong, Renhua Wu
• Journal: Oncotarget (Oncotarget) Vol. 8 Issue 28 Pg. 45759-45767 (Jul 11 2017) ISSN: 1949-2553 [Electronic] United States
• PMID: 28501855 (Publication Type: Journal Article)

Chemical References

• Biomarkers
• Contrast Media
• Triiodobenzoic Acids
• ioversol

Topics

• Animals
• Biomarkers
• Breast Neoplasms (diagnostic imaging, metabolism)
• Cell Line, Tumor
• Contrast Media
• Disease Models, Animal
• Extracellular Space
• Female
• Hydrogen-Ion Concentration
• Liver Neoplasms (diagnostic imaging, metabolism)
• Magnetic Resonance Imaging (methods)
• Mice
• Mice, Transgenic
• Phantoms, Imaging
• Rats
• Triiodobenzoic Acids (chemistry)