Development of 177Lu-scFvD2B as a Potential Immunotheranostic Agent for Tumors Overexpressing the Prostate Specific Membrane Antigen

Abstract The clinical translation of theranostic 177Lu-radiopharmaceuticals based on inhibitors of the prostate-specific membrane antigen (PSMA) has demonstrated positive clinical responses in patients with advanced prostate cancer (PCa). However, challenges still remain, particularly regarding thei...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Debora Carpanese, Guillermina Ferro-Flores, Blanca Ocampo-Garcia, Clara Santos-Cuevas, Nicola Salvarese, Mariangela Figini, Giulio Fracasso, Laura De Nardo, Cristina Bolzati, Antonio Rosato, Laura Meléndez-Alafort
Formato: article
Lenguaje:EN
Publicado: Nature Portfolio 2020
Materias:
R
Q
Acceso en línea:https://doaj.org/article/9b2d1ad6b66740dab5e3f6564255938b
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
Descripción
Sumario:Abstract The clinical translation of theranostic 177Lu-radiopharmaceuticals based on inhibitors of the prostate-specific membrane antigen (PSMA) has demonstrated positive clinical responses in patients with advanced prostate cancer (PCa). However, challenges still remain, particularly regarding their pharmacokinetic and dosimetric properties. We developed a potential PSMA-immunotheranostic agent by conjugation of a single-chain variable fragment of the IgGD2B antibody (scFvD2B) to DOTA, to obtain a 177Lu-labelled agent with a better pharmacokinetic profile than those previously reported. The labelled conjugated 177Lu-scFvD2B was obtained in high yield and stability. In vitro, 177Lu-scFvD2B disclosed a higher binding and internalization in LNCaP (PSMA-positive) compared to PC3 (negative control) human PCa cells. In vivo studies in healthy nude mice revealed that 177Lu-scFvD2B present a favorable biokinetic profile, characterized by a rapid clearance from non-target tissues and minimal liver accumulation, but a slow wash-out from kidneys. Micro-SPECT/CT imaging of mice bearing pulmonary microtumors evidenced a slow uptake by LNCaP tumors, which steadily rose up to a maximum value of 3.6 SUV at 192 h. This high and prolonged tumor uptake suggests that 177Lu-scFvD2B has great potential in delivering ablative radiation doses to PSMA-expressing tumors, and warrants further studies to evaluate its preclinical therapeutic efficacy.