@article {Ryu1178, author = {Eun Kyoung Ryu and Sung-Min Kim and Min Su Yim}, title = {Synthesis and evaluation of radiolabeled oleanolic acid for diagnosis of colon cancer using PET}, volume = {54}, number = {supplement 2}, pages = {1178--1178}, year = {2013}, publisher = {Society of Nuclear Medicine}, abstract = {1178 Objectives Oleanolic acid (OA) is a pentacyclic triterperioid found in a variety of plant species and has been shown to inhibit tumor proliferation and induce apoptosis in human colon cancer. In this study, we synthesized and evaluated OA derivative for inhibition effect of the cell proliferation on human colon cancer. Its radioligand was prepared for non-invasively monitoring tumor progression in vitro and in vivo. Methods Amine modification of OA was accomplished by activation of carboxyl group of OA (20 mg, 0.04 mmol) with peptide bond agents in the basic condition for 20 min at room temperature followed by addition of N-Boc-ethylenediamine (26 mg, 0.13 mmol) for overnight and purified. The product was added to p-SCN-NOTA for radiolabeling with 68Ga. 68Ga-NOTA-OA was injected to the HT-29 tumor xenografted mice for PET imaging and biodistribution studies. Results OA decreased the cell survive on treatments concentration-dependently and increased apoptosis in HT29. The IC50 value determined for the inhibition of the proliferation was 28.32 μM by XTT assay. OA induced down-regulation of CyclinD1, Cox-2, Bcl-2 and Bcl-xL mRNA, and increased inhibitor factor of apoptosis, Bax mRNA expression in OA treated HT29 cells. In addition, the expression of NF-kB p65 and IkB also decreased, but apoptosis marker, cleavage form PARP-1 was significantly increased in OA treated HT29 cells. The radioligand, 68Ga-NOTA-OA was showed significantly high tumor uptake in the biodistribution and PET imaging studies with in human colon cancer xenograft model. Conclusions Therefore, we synthesized and evaluated derivative from natural compound, OA for inhibition effect of the cell proliferation on human colon cancer. Moreover its radioligand demonstrated the cancer diagnosis ability in vivo and target to colon cancer cell in vitro. In conclusions, our results demonstrated that OA has promising properties for an anticancer and diagnosis of tumor.}, issn = {0161-5505}, URL = {https://jnm.snmjournals.org/content/54/supplement_2/1178}, eprint = {https://jnm.snmjournals.org/content}, journal = {Journal of Nuclear Medicine} }