Chromosomal Alteration and Development of Tumors. XXI. Cytogenetic Studies of Primary Plasma-Cell Neoplasms Induced in BALB/c Mice

Summary

Plasma cell tumors developed in the peritoneum of 19 BALB/c mice after injection of Freund adjuvant. We studied the chromosomes in 14 primary tumors; 3 had diploid, 1 had hyperdiploid (44), and the remaining 10 had hypotetraploid or hypertetraploid chromosomes. In tumors developing shortly after treatment, diploid or ncar-diploid cells were more frequent, whereas in those appearing a long time after treatment, polyploid cells were more frequent. Diploidy of primary tumors changed to neartetraploidy after 1–2 transplant generations. Therefore, it is assumed that mouse plasma-cell tumors can develop from cells with diploid chromosome numbers, but may change easily to aneuploidy during further growth.