Amplification of c-myc by fluorescence in situ hybridization in a population-based breast cancer tissue array.
A total of 261 primary breast carcinomas were analyzed for amplification of the c-myc oncogene by fluorescence in situ hybridization performed on tumor tissue array samples. Results were compared with individual clinicopathologic and follow-up data. Thirty-eight (14.6%) of the tumors showed c-myc gene amplification (defined as two or more additional copies of c-myc gene in relation to the number of chromosome 8 centromere). The reproducibility of fluorescence in situ hybridization assay (defined by hybridization with two different myc probes) was good (kappa coefficient 0.402). Statistically significant associations were found between c-myc amplification and DNA aneuploidy (P =.0011), and progesterone receptor negativity (P =.0071), and c-myc amplification also tended to be associated with high histologic grade (P =.064), positive axillary nodal status (P =.080), and a high S-phase fraction (P =.052). c-myc amplification was not significantly associated with overall survival of patients with invasive cancer (P =.32). These data from a population-based tumor material suggest that c-myc amplification is a feature of aggressive breast cancers, but that it is unlikely to be a clinically useful prognostic factor.
Rummukainen
J K
JK
Laboratory of Cancer Genetics, Institute of Medical Technology, University of Tampere and Tampere University Hospital, Tampere Finland. jaana.rummukainen@uta.fi
Salminen
T
T
Lundin
J
J
Kytölä
S
S
Joensuu
H
H
Isola
J J
JJ
D000782:Aneuploidy; D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology; D002503:Centromere / Q000235:genetics; D002898:Chromosomes, Human, Pair 8 / Q000235:genetics; D005260:Female; D005784:Gene Amplification; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D008875:Middle Aged; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics*; D011980:Receptors, Progesterone / Q000378:metabolism; D016019:Survival Analysis
D016271:Proto-Oncogene Proteins c-myc; D011980:Receptors, Progesterone