title: Hypoxic fractions in xenografted human colon tumors.
abstract: We investigated the percentage of radiobiologically hypoxic cells within 11 different xenografted human colon tumors using an in vivo-in vitro excision assay technique. Tumors were excised at average volumes of 750 mm3, and it was found that hypoxic fractions varied from less than 1% (clone D) to over 80% (HCT-8). The geometric mean hypoxic percentage was 10.4% (95% confidence interval, 4.9 to 22.1%). Comparison of the percentage of hypoxia results from the xenografted human colon tumors to published data from xenografted melanomas suggests that transplanted colorectal tumors as a class contain significantly less hypoxia than do the melanomas.
authors.affiliation: Brown University Radiation Research Laboratories, Department of Radiation Medicine, Providence, Rhode Island 02912.
authors.forename: J T
authors.initials: JT
authors.lastname: Leith
authors.forename: G
authors.initials: G
authors.lastname: Padfield
authors.forename: L
authors.initials: L
authors.lastname: Faulkner
authors.forename: S
authors.initials: S
authors.lastname: Michelson
mesh_terms: D000818:Animals; D015687:Cell Hypoxia; D002470:Cell Survival / Q000528:radiation effects; D003110:Colonic Neoplasms / Q000473:pathology*; D003114:Colony-Forming Units Assay; D004307:Dose-Response Relationship, Radiation; D005720:Gamma Rays; D006801:Humans; D008297:Male; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D014183:Transplantation, Heterologous