Tumor receptors

B8. Blarney, R. W., Bishop, H. M., Blake, J., Doyle, P. J., Elston, C., Haybrittle, J. L., Nicholson, R. 1., and Griffiths, K., Relationship between primary breast tumor receptor status and patient survival. Cancer (Philadelphia) 46, 2765-2769 (1980). 

Table 1.5 Examples of Tumor Receptor Targeting Imaging Tracers...

Some of the more widely studied tumor receptors include somatostatin receptors, vasoactive intestinal peptide (VIP) receptors, gastrin-releasing... 

Indium-111. Kits for labeling using other radionucHdes include two indium-111 compounds. Indium-111 pentetreotide is used for the scintigraphic localization of primary and metastatic neuroendocrine tumors bearing somatostatin receptors. For octreotide DTP A, the active agent is suppHed in a lyopbilized kit with gentisic acid, citrate buffer, and inositol. 

Whereas epidermal growth factor (EGF) enhances the radiosensitivity of human squamous ceU carcinoma cells in vitro (197), addition of EGF to hormone-deprived MCE-7 breast cancer cells prior to irradiation results ia iacreased radioresistance (198). An anti-EGE-receptor monoclonal antibody blocks the abiUty of EGE to enhance growth and radioresistance. Tumor cells, the growth of which is stimulated by EGE, appear to be protected those where growth is iohibited are sensitized (198). 

A 2-h incubation with another PGE2 analogue, nocloprost (9P-chloro-DMPG) protects normal human fibroblasts but has no effect on the survival of colon adenocarcinoma cells exposed to 10 Gy (1000 rad) (218). Nocloprost protects against radiation-induced DSBs in normal cells but not in tumor cells. Moreover, incubation using nocloprost for 2 h after irradiation enhances the rate of DSB rejoining in fibroblasts but not in adenocarcinoma cells. These data possibly reflect a different distribution of PG receptors on the plasma membrane of the two cell types. 

Conjugation of DOX with copolymers or peptides Recognition of DOX by tumor-specific receptors or proteases Investigational... 

VEGF-R1/ VEGF-R2 Growth factor receptors Decrease of in vivo tumor growth decrease of in vivo metastatic ability (VEGF-R2 only)... 

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