Atypical Cells in the Peripheral Blood A Cytological Study Applied to Cancer Research

DNA Content and Chromosome Number in Twenty–five Human Carcinomas

“…This agrees with the concepts of A t k i n et al [7], F o r d and C l a r k e [17], L e j e u n e [19], L e v a n and B i e s e l e [23] and P a u l e t e -V a n r e l l [30] who have already proposed the existence of cancer cell stem-lines. Each tumour arises, according to this concept, as a clone from one single atypical cell in which the chromosomal changes first appeared.…”

“…A t k i n and B a k e r [10], A t k i n and R i c h a r d s [12], P a u l e t e -V a n r e l l [30] and P a u l e t e -V a n r e l l and C a m a c h o d e O s o r io [32] have demonstrated that the DNA content per chromosome, even when the chromosome number is increased, is almost the same as the DNA content of normal chromo somes in diploid somatic cells. Thus it seems that in most of the cases some degree of balance and homeostasis in the karyotype must be maintained.…”

“…prognosis as the studies of A t k i n [1,3,4], A t k i n et a/. [13], H a u s c h k a et al [18], P a u l e t e -V a n r e l l [30], P a u l e t e -V a n r e l l et al [33] and R e v e s z and N o r m a n [34,35] indicate. Unfortunately, chromosome studies in tumours cannot be undertaken as a routine.…”

“…DNA/ chromosome ratio and 5. large/small chromosome ratio. All values were calculated according to methods previously described [10,30,32], The karyotypes were mounted by routine procedures and morphological investiga tions were carried out at convenient enlargement. The morphometric classification o f the tumour cell chromosomes followed the system of L evan et at.…”

“…Further changes are almost always present. For instance, a double breakage of the DNA helix can occur with subsequent repair by means of rearrangement instead of the customary overlook procedures [30] or new polynucleotide chains can be created, as the DNA measurements show. Both types of changes result in a mis reading of the genetic code or even in the writing of new genetic informations.…”