TY - JOUR
T1 - Potential of [11C](R)-PK11195 PET Imaging for Evaluating Tumor Inflammation
T2 - A Murine Mammary Tumor Model
AU - de Souza, Aline Morais
AU - Real, Caroline Cristiano
AU - Junqueira, Mara de Souza
AU - Estessi de Souza, Larissa
AU - Navarro Marques, Fábio Luiz
AU - Buchpiguel, Carlos Alberto
AU - Chammas, Roger
AU - Sapienza, Marcelo Tatit
AU - de Paula Faria, Daniele
PY - 2022/12
Y1 - 2022/12
N2 - Background: Breast tumor inflammation is an immunological process that occurs mainly by mediation of Tumor-Associated Macrophages (TAM). Aiming for a specific measurement of tumor inflammation, the current study evaluated the potential of Positron Emission Tomography (PET) imaging with [11C](R)-PK11195 to evaluate tumor inflammation in a mammary tumor animal model. Methods: Female Balb/C mice were inoculated with 4T1 cells. The PET imaging with [11C](R)-PK11195 and [18F]FDG was acquired 3 days, 1 week, and 2 weeks after cell inoculation. Results: The [11C](R)-PK11195 tumor uptake increased from 3 days to 1 week, and decreased at 2 weeks after cell inoculation, as opposed to the [18F]FDG uptake, which showed a slight decrease in uptake at 1 week and increased uptake at 2 weeks. In the control group, no significant differences occurred in tracer uptake over time. Tumor uptake of both radiopharmaceuticals is more expressed in tumor edge regions, with greater intensity at 2 weeks, as demonstrated by [11C](R)-PK11195 autoradiography and immunofluorescence with TSPO antibodies and CD86 pro-inflammatory phenotype. Conclusion: The [11C](R)-PK11195 was able to identify heterogeneous tumor inflammation in a murine model of breast cancer and the uptake varied according to tumor size. Together with the glycolytic marker [18F]FDG, molecular imaging with [11C](R)-PK11195 may provide a better characterization of inflammatory responses in cancer.
AB - Background: Breast tumor inflammation is an immunological process that occurs mainly by mediation of Tumor-Associated Macrophages (TAM). Aiming for a specific measurement of tumor inflammation, the current study evaluated the potential of Positron Emission Tomography (PET) imaging with [11C](R)-PK11195 to evaluate tumor inflammation in a mammary tumor animal model. Methods: Female Balb/C mice were inoculated with 4T1 cells. The PET imaging with [11C](R)-PK11195 and [18F]FDG was acquired 3 days, 1 week, and 2 weeks after cell inoculation. Results: The [11C](R)-PK11195 tumor uptake increased from 3 days to 1 week, and decreased at 2 weeks after cell inoculation, as opposed to the [18F]FDG uptake, which showed a slight decrease in uptake at 1 week and increased uptake at 2 weeks. In the control group, no significant differences occurred in tracer uptake over time. Tumor uptake of both radiopharmaceuticals is more expressed in tumor edge regions, with greater intensity at 2 weeks, as demonstrated by [11C](R)-PK11195 autoradiography and immunofluorescence with TSPO antibodies and CD86 pro-inflammatory phenotype. Conclusion: The [11C](R)-PK11195 was able to identify heterogeneous tumor inflammation in a murine model of breast cancer and the uptake varied according to tumor size. Together with the glycolytic marker [18F]FDG, molecular imaging with [11C](R)-PK11195 may provide a better characterization of inflammatory responses in cancer.
KW - 4T1 cells
KW - breast cancer
KW - inflammation
KW - macrophages
KW - positron emission tomography
KW - TSPO
KW - [C](R)-PK11195
UR - https://www.scopus.com/pages/publications/85144838865
U2 - 10.3390/pharmaceutics14122715
DO - 10.3390/pharmaceutics14122715
M3 - Journal article
C2 - 36559209
AN - SCOPUS:85144838865
SN - 1999-4923
VL - 14
JO - Pharmaceutics
JF - Pharmaceutics
IS - 12
M1 - 2715
ER -