[Effects of high temperatures on chromosomes of normal and transformed human cells]

The effects of the high temperature on the chromosome of normal and transformed human cells were examined using a temperature gradient incubator (T.G.I., Model TN-212) in culture. The cell nucleus were damaged, specifically fragmentation occurred under the hyperthermic treatments. The diploid cells were passaged at three different temperature conditions ranging from 39.0-41.5 degrees C. It was found that the polyploid cells (predominantly tetraploid) were increased in these conditions compared with the cells cultured at 37 degrees C. We observed the chromosomal aberrations (break, stickiness, fragmentation, etc.) in the cells treated with high temperature for the various periods of time. The results indicated that the transformed cells were more high-temperature sensitive than the normal cells with respect to the chromosomal aberrations. The trend was seen in this experiment, in which the chromatid breaks of HAIN-55 and MKN-1 cell strains occurred more on the large chromosomes such as the ones in group A, B and C under the hyperthermic treatments.