S E Miranda1, J A Lemos1, R S Fernandes2, F M Ottoni2, R J Alves2, A Ferretti3, D Rubello4, V N Cardoso1, A L Branco de Barros5. 1. Department of Clinical and Toxicological Analysis, Faculty of Pharmacy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brasil. 2. Department of Pharmaceutical Products, Faculty of Pharmacy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brasil. 3. Department of Nuclear Medicine, Radiology, NeuroRadiology, Medical Physics, Clinical Laboratory, Microbiology, Pathology, Santa Maria della Misericordia Hospital, Rovigo, Italia. 4. Department of Nuclear Medicine, Radiology, NeuroRadiology, Medical Physics, Clinical Laboratory, Microbiology, Pathology, Santa Maria della Misericordia Hospital, Rovigo, Italia. Electronic address: domenico.rubello@libero.it. 5. Department of Clinical and Toxicological Analysis, Faculty of Pharmacy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brasil. Electronic address: brancodebarros@yahoo.com.br.
Abstract
OBJECTIVE: Breast cancer is a health problem worldwide with high incidence and mortality rates. It is well known that the development of more sensitive and specific diagnostic methods is of great importance since an early diagnosis is essential to successfully treat tumors. Lapachol is a natural compound, belonging to the naphthoquinone group that has been widely used in traditional medicine to treat various illnesses, including cancer. The aim of this study was to evaluate technetium-99m (99mTc) labeled lapachol as an imaging probe for breast cancer identification. METHODS: To achieve this purpose, lapachol was labeled with 99mTc, radiochemical purity and in vitro stability were determined. Blood clearance, in healthy mice, and biodistribution, in 4T1 tumor-bearing mice, were also evaluated. RESULTS: Lapachol was successfully labeled with 99mTc, with high values of radiochemical yield (95.9±3.4%). In vitro stability showed that the radiolabeled complex remained stable for up to 24h, with values above 90% for both saline and plasma (95.6±3.6% and 96.4±1.7%, respectively). The radiolabeled complex decays in a biphasic manner, with a half-life of distribution and elimination equal to 3.3 and 50.0min, respectively. Biodistribution and scintigraphic images showed high uptake in organs of excretion (kidneys, liver, and intestine). It could be also noted that tumor uptake was higher than the muscle at all time points. Tumor-to-muscle ratio reaches ∼4.5 at 24h after administration. CONCLUSION: These findings suggest that 99mTc-lapachol can be a potential diagnostic agent for breast tumors.
OBJECTIVE:Breast cancer is a health problem worldwide with high incidence and mortality rates. It is well known that the development of more sensitive and specific diagnostic methods is of great importance since an early diagnosis is essential to successfully treat tumors. Lapachol is a natural compound, belonging to the naphthoquinone group that has been widely used in traditional medicine to treat various illnesses, including cancer. The aim of this study was to evaluate technetium-99m (99mTc) labeled lapachol as an imaging probe for breast cancer identification. METHODS: To achieve this purpose, lapachol was labeled with 99mTc, radiochemical purity and in vitro stability were determined. Blood clearance, in healthy mice, and biodistribution, in 4T1 tumor-bearing mice, were also evaluated. RESULTS:Lapachol was successfully labeled with 99mTc, with high values of radiochemical yield (95.9±3.4%). In vitro stability showed that the radiolabeled complex remained stable for up to 24h, with values above 90% for both saline and plasma (95.6±3.6% and 96.4±1.7%, respectively). The radiolabeled complex decays in a biphasic manner, with a half-life of distribution and elimination equal to 3.3 and 50.0min, respectively. Biodistribution and scintigraphic images showed high uptake in organs of excretion (kidneys, liver, and intestine). It could be also noted that tumor uptake was higher than the muscle at all time points. Tumor-to-muscle ratio reaches ∼4.5 at 24h after administration. CONCLUSION: These findings suggest that 99mTc-lapachol can be a potential diagnostic agent for breast tumors.
Authors: Sued Eustáquio Mendes Miranda; Janaína de Alcântara Lemos; Renata Salgado Fernandes; Juliana de Oliveira Silva; Flaviano M Ottoni; Danyelle M Townsend; Domenico Rubello; Ricardo José Alves; Geovanni Dantas Cassali; Lucas Antônio Miranda Ferreira; Andre Luis Branco de Barros Journal: Biomed Pharmacother Date: 2020-11-27 Impact factor: 6.529