[Analysis of and repair capacity in 247 cancer patients and normal persons by nucleoid sedimentation technique].

The nucleoid sedimentation technique was developed to analyze DNA repair capacity in 108 cancer patients (esophageal cancer 34, lung cancer 24 and ovarian cancer 50) and 139 normal persons. After exposing lymphocytes to UV in radiation at the dose of 2.5 microJ/mm2, the cells were incubated for different periods of time at 37 degrees C for repairing the damaged DNA. The nucleoid sedimentation distance which corresponds to DNA repair capacity was determined. It was found that most normal persons finished the process of DNA repair in II hours while the cancer patients could not do so even 17 hours after incubation. This study showed that decreased DNA repair capacity may be a component of the genetically determined susceptibility to cancer.