title: 177Lu-DOTA-lanreotide: a novel tracer as a targeted agent for tumor therapy.
abstract: 177Lu of specific activity approximately 100-110 TBq/g and radionuclidic purity of approximately 100% was obtained by irradiation of enriched Lu2O3 (60.6% 176Lu) target for 7 days at a thermal neutron flux of 3 x 10(13)n/cm2/sec. The 177Lu labeling of a macrocyclic bifunctional chelating agent viz. 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) has been extensively studied. Lanreotide, [beta-naphthyl-Ala-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH2] a disulfide-linked cyclic octapeptide and a somatostatin analog, reported to bind with a wide variety of tumors expressing somatostatin receptors, was conjugated with DOTA. The peptide-BFCA conjugate was characterized with the help of high-resolution two-dimensional proton NMR spectroscopy. The 177Lu labeling of the DOTA-lanreotide conjugate has been standardized to give a radiolabeling yield of 85%. The tracer showed specific binding with A-431 human epidermoid carcinoma and IMR-32 human brain neuroblastoma cells.
authors.affiliation: Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Mumbai-400 085, India.
authors.forename: Sharmila
authors.initials: S
authors.lastname: Banerjee
authors.forename: Tapas
authors.initials: T
authors.lastname: Das
authors.forename: Sudipta
authors.initials: S
authors.lastname: Chakraborty
authors.forename: Grace
authors.initials: G
authors.lastname: Samuel
authors.forename: Aruna
authors.initials: A
authors.lastname: Korde
authors.forename: Sudha
authors.initials: S
authors.lastname: Srivastava
authors.forename: Meera
authors.initials: M
authors.lastname: Venkatesh
authors.forename: M R A
authors.initials: MR
authors.lastname: Pillai
mesh_terms: D045744:Cell Line, Tumor; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D004355:Drug Stability; D006573:Heterocyclic Compounds, 1-Ring / Q000138:chemical synthesis* / Q000627:therapeutic use*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009369:Neoplasms / Q000532:radiotherapy*; D010456:Peptides, Cyclic / Q000138:chemical synthesis* / Q000627:therapeutic use*; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000532:radiotherapy; D011786:Quality Control; D019275:Radiopharmaceuticals / Q000138:chemical synthesis* / Q000627:therapeutic use*; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: C496695:177Lu-DOTA-lanreotide; D006573:Heterocyclic Compounds, 1-Ring; D010456:Peptides, Cyclic; D019275:Radiopharmaceuticals