[A cytogenic study on colorectal carcinoma].

OBJECTIVE

To study the cytogenesis of colorectal carcinoma and to look for colorectal carcinoma related chromosomal fragility sites which could facilitate screening of high risk colorectal carcinoma patients.

METHODS

20 cases of surgically resected colorectal carcinomas and 4 cell lines were analysed cytogenetically.

RESULTS

Most of the tumor cells were heteroploid, the chromosome number was predominately hypodiploid. Karyotypic analysis demonstrated an increase of chromosome 13, and loss of chromosome 17 and chromosome 1 appeared frequently. The most frequently found structural abnormalities in colorectal carcinoma were breakpoint 1q21 and 1p13. Highly non-random cancer chromosome breakpoints and fragile sites were compared with the oncogene locus and found that their locus or neighboring locus was 1q21.

CONCLUSION

The results suggest that breakpoint 1q21 may be related to tumorgenesis and may be useful in screening and preventing colorectal carcinoma.