摘要:

Previous studies on mice carrying melanoma have shown that 5-iodo-2-thiouracil (ITU) is accumulated in the tumours due to its specific incorporation into melanin during its synthesis. ITU is also selectively localized in murine melanoma metastases and in cultured human melanoma cells. Progresssive formation of melanin is, however, a prerequisite for the incorporation. Four patients with disseminated melanoma were injected intravenously with 39–62 MBq [131I]TU. Blood and urine samples were gradually collected, and 3–7 days postinjection tumours were biopsied and examined by impulse counting. The patients were scanned with a gamma camera over the total body daily for 3–4 days. The radioactivity was rapidly excreted. Poor melanin pigmentation of the tumours and low proliferation rate (possibly induced by chemotherapy) decreased the uptake of radioactivity by the tumours, and no imaging was possible. One of the patients, however, had clearly progressive disease with darkly pigmented metastases which contained considerably higher levels of radioactivity than the surrounding skin. Calculations indicated that a doubling of the radioiodine dose would probably make visualization of the tumours possible.

ISSN:0960-8931    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

We have established methods of targeting a sufficient number of10B atoms on human melanoma cells to allow selective destruction of the cancer cells by thermal neutron irradiation. Thermal neutron capture therapy (NCT)1–3requires the presence of at least 10910B atoms on each target cell for specific killing of that cell without injuring normal tissues.4,5In order to accumulate an adequate number of10B atoms on target cells, we first created an effective compound containing 12 atoms of10B per molecule (10B12-chlorpromazine)6,7and10B-dopa analogue (10B1-paraboronophenylalanine).6,8In the present study, about three molecules of our newly synthesized10B12-compound were conjugated to an avidin molecule. The resulting10B38.5-avidin compound can be specifically directed to human melanoma cells by biotinated monoclonal antibodies (MAbs) specific for the cells. We were able to accumulate 2.6x10810B atoms on a melanoma cell using this method. Cultured human melanoma cells treated with10B-avidin-biotin-MAb10B-AB-MAb) were selectively damaged by thermal neutron irradiationin vitro.This is the first study to indicate that thermal neutrons selectively damage target cells boronated by MAbs.

ISSN:0960-8931    

出版商:OVID    

年代:1992

数据来源: OVID

ISSN:0960-8931    

出版商:OVID    

年代:1992

数据来源: OVID