THE RELATIONSHIP BETWEEN NUMERICAL ABERRATIONS OF CHROMOSOME-17 AND NUCLEAR-DNA CONTENT IN COLORECTAL-CARCINOMA DETECTED BY FLUORESCENT IN-SITU HYBRIDIZATION (FISH) AND CYTOFLUOROMETRY USING AUTO-SCANNING STAGE
K. Kawai et al., THE RELATIONSHIP BETWEEN NUMERICAL ABERRATIONS OF CHROMOSOME-17 AND NUCLEAR-DNA CONTENT IN COLORECTAL-CARCINOMA DETECTED BY FLUORESCENT IN-SITU HYBRIDIZATION (FISH) AND CYTOFLUOROMETRY USING AUTO-SCANNING STAGE, Acta histochemica et cytochemica, 30(5-6), 1997, pp. 665-673
Recently, interphase cytogenetics using fluorescent in situ hybridizat
ion (FISH) was performed on various kinds of solid tumor, and their in
herent karyotypic heterogeneities were revealed. Concerning this heter
ogeneity, we evaluated both the exhibiting number of chromosome 17 and
nuclear DNA content on an identical nucleus by means of computer-cont
rolled auto-scanning stage in order to demonstrate the alteration in n
umber of chromosome 17 among cytofluorometrically distinct subpopulati
ons. We investigated 8 lesions of surgically resected colorectal carci
nomas, which were classified as aneuploid in quantitative DNA analysis
and also exhibited an increase of 17-aneusomy nuclei. We used paraffi
n-embedded archival blocks. First, we prepared isolated cell specimens
, and memorized the position of the cells on a glass slide using compu
ter-controlled auto-scanning stage. Next, the specimens were stained w
ith propidium iodide, and the fluorescent intensity was evaluated as n
uclear DNA content in the order of cell position data. And lastly, FIS
H was performed with (peril centromere-specific DNA probes for chromos
ome 17, and we enumerated the number of signals in a nucleus also acco
rding to cell position data. Then, we compared the distribution of num
ber of chromosome 17 among cytofluorometrically distinct subpopulation
s. Three of 8 lesions showed a single G0+G1 peak, and the rest exhibit
ed plural G0+G1 peaks in DNA profile. And 4 of 5 lesions, which showed
plural G0+G1 peaks, presented a peak at the DNA value of (near) 2c. W
e could detect an alteration in the distribution of number of chromoso
me 17 between diploid peak and aneuploid peaks in 4 of 4 lesions which
presented a peak at the DNA value of (near) 2c. However, we could not
find a difference in the distribution of number of chromosome 17 betw
een G0+G1 peak and G2+M peak. These observations indicate that the dis
tribution of number of chromosome 17 reflects an endoreduplication of
genome content, yet, it does not alter in accordance with the phase of
cell cycle. It is necessary to evaluate nuclear DNA content simultane
ously in order to assess an essential cytogenetic change.