Spectral karyotyping of the human colon cancer cell lines SW480 and SW620

The cell lines SW480 and SW620, derived from different stages of colon carc inoma in the same patient, have been used for a number of biochemical, immu nological, and genetic studies on colon cancer. A comparative analysis of t heir karyotypes may identify chromosomal aberrations that might represent m arkers for metastatic spread. In the present study spectral karyotyping (SK Y) was applied to these two colon cancer cell lines. Compared to previously reported G-banded karyotypes, 9 (SW480) and 7 (SW620) markers were identic al, 3 (SW480) and 3 (SW620) markers could be redefined, 5 (SW480) and 8 (SW 620) markers were newly identified, and 4 (SW480) and 5 (SW620) of the prev ious described markers could not be confirmed. The redefined aberrations in clude very complex rearrangements, such as a der(16) t(3;16;1;16;8;16; 1;16 ;10) and a der(18)t(18;15;17)(q12; p11p13;??) in SW620 and a der(19)t(19;8; 19;5) in SW480, that have not been identified by conventional banding techn iques. The resulting chromosome gains (5q11-->5q15, 7pter-->q22, 11, 13q14- ->qter, 20pter-->p12, X) and losses (8pter-->p2, 18q12-->qter, Y) found in both SW480 and SW620 were in good agreement with those frequently described in colorectal tumors as primary changes in the stem cell. Abnormalities fo und exclusively in SW620 cells only (gains of 5pter-->5q11, 12q12-->q23, 15 p13-->p11, and 16q21-->q24 and losses of 2pter-->2p24, 4q28-->qter, and 6q2 5-->qter) can be viewed as changes that occurred in a putative metastatic f ounder cell. Copyright (C) 2000 S. Karger AG, Basel.