CLONAL ANALYSIS BY PCR AND RFLP IN BREAST-CANCER AND PRECANCEROUS LESIONS - PRELIMINARY DATA

In order to investigate the clonality in various benign, precancerous and malignant breast lesions, we analyzed small DNA samples from paraf fin sections of various breast lesions by polymerase chain reaction (P CR) and restriction fragment length polymorphism (RFLP) of the X-chrom osome- linked phosphoglycerokinase (PGK) gene. DNA from the lesion as well as from the adjacent normal tissue were analyzed in each case. Tw o restriction endonucleases, Hpa-II, a methylation sensitive restricti on enzyme and Bst XI, a restriction endonuclease, which recognizes thi s polymorphic site on the PGK gene, were used. Of 19 cases, one case o f in situ ductal Ca (DCIS), two cases of invasive ductal Ca and one ca se of multifocal ductal Ca were shown to be monoclonal. Two cases of i ntraductal papillomas were found to be polyclonal. One case of atypica l ductal hyperplasia showed no conclusive findings. Additionally DNA w as not yielded from 3 cases and other 7 cases were not informative, de rived from females homozygotes. Further study of a larger number of ca ses is in progress.