BALB/c female mice were injected with 5 × 105 Renca RCC tumor cells and treated with sunitinib (40 mg/kg/d) and sacrificed after 1 month. Experiments were approved by the Institutional Care and Use Committee at the Johns Hopkins Medical Institutions and in accordance with the NIH Guide for the care and use of laboratory animals.
Three patients diagnosed with advanced malignancies [malignant solitary fibrous tumor, colorectal cancer (CRC), and leiomyosarcoma] were treated with sunitinib in context of a clinical trial at a dose of 37.5 to 50 mg/d for at least 4 weeks. Tumors of these patients were biopsied and in parallel plasma samples were collected. The use of these samples was in accordance with the local ethical guidelines at VU University Medical Center. For the determination of sunitinib in tissue (tumor or skin), an amount of about 10 mg of snap frozen tissue was cut, put into a vial and weighed. A total of 200 μL of water was added, the sample was snap-frozen and freeze-dried overnight. For extraction, 200 μL of ice-cold 83% acetonitrile (ACN) was added and left on ice for 1 hour. After centrifugation, 50 μL of super-natant was transferred for subsequent liquid chromatography—tandem mass spectrometry (LC/MS-MS) analysis as reported previously for plasma and cell pellet homogenates (13 ). The data are expressed in micromole to allow comparison of tissue concentrations with the IC50 values in cell culture and are based on the conversion of 1 g tissue to 1 mL liquid (14 (link)).
Three patients diagnosed with advanced malignancies [malignant solitary fibrous tumor, colorectal cancer (CRC), and leiomyosarcoma] were treated with sunitinib in context of a clinical trial at a dose of 37.5 to 50 mg/d for at least 4 weeks. Tumors of these patients were biopsied and in parallel plasma samples were collected. The use of these samples was in accordance with the local ethical guidelines at VU University Medical Center. For the determination of sunitinib in tissue (tumor or skin), an amount of about 10 mg of snap frozen tissue was cut, put into a vial and weighed. A total of 200 μL of water was added, the sample was snap-frozen and freeze-dried overnight. For extraction, 200 μL of ice-cold 83% acetonitrile (ACN) was added and left on ice for 1 hour. After centrifugation, 50 μL of super-natant was transferred for subsequent liquid chromatography—tandem mass spectrometry (LC/MS-MS) analysis as reported previously for plasma and cell pellet homogenates (13 ). The data are expressed in micromole to allow comparison of tissue concentrations with the IC50 values in cell culture and are based on the conversion of 1 g tissue to 1 mL liquid (14 (link)).
