Use of ¹¹¹In–L–LDL radiotracers to detect human pancreatic and mice melanoma tumors

Abstract

The present study was designed to evaluate the potential of labeled low-density lipoprotein with 111 In using a lipid chelating agent (bis(stearylamide) of diethylenetriaminepentaacetic acid: L) to detect pancreatic tumors and melanoma in mice by gamma-scintigraphy. We compare the biodistribution of radioactivity and scintigraphic images in nude mice heterotransplanted with human cancerous pancreatic duct cells (Capan-1) and in mice transplanted with murine tumor cells (B16 melanoma). Biodistribution studies showed that radioactivity was twice as high in the Capan-1 xenograft after injection of the radiolabel than after injection of radiometal alone, and 34-fold higher in the B16 tumor. On gamma-scintigraphic imaging, the Capan-1 tumor was just visible, whereas the B16 melanoma was clearly imaged. The lack of contrast of the Capan-1 tumor compared with the B16 melanoma could be due to a poor vascularization.

111In–L–LDL and 153Gd–L–LDL as radiotracers for detection of AR4‐2J rat pancreatic tumors

“…In a previous study, we suggested that the ability of 111 In-L-LDL tracers to detect human pancreatic tumors by scintigraphy depended on the degree of vascularization of the tumor. 18 To support this interpretation, we investigated strongly vascularized pancreatic xenografts. Various cancerous human pancreatic lineages maintained in vitro have been heterotransplanted into nude mice to determine the extent of angiogenesis.…”

“…17 This was accounted for by weak angiogenesis after heterotransplantation into nude mice of Capan-1 cells in contrast to the strong angiogenesis observed in xenografts of human melanoma cells. 18 Here, we present results in favor of this hypothesis using cancerous pancreatic cells of the AR4-2J line heterotransplanted into nude mice. These xenografts of rat origin are strongly vascularized in this host.…”

“…17 A recent study on pancreatic adenocarcinomas, however, gave disappointing results. 18 We found that LDL labeled with radioactive indium did not readily reach pancreatic xenografts produced by inoculation of nude mice with cancerous human pancreatic duct cells of the Capan-1 line, whereas, in vitro, such particles Bioorganometallic Chemistry bound to the surface of cells and were internalized by them. 17 This was accounted for by weak angiogenesis after heterotransplantation into nude mice of Capan-1 cells in contrast to the strong angiogenesis observed in xenografts of human melanoma cells.…”