High frequency of allelic imbalance at chromosome region 16q22-23 in human breast cancer: correlation with high PgR and low S phase.
The loss of genetic material from a specific chromosome region in tumors suggests that presence of tumor-suppressor genes. Loss of heterozygosity (LOH) or allelic imbalance (AI) on the long arm of chromosome 16 is a known event in sporadic breast cancer. To locate the commonly deleted regions, and therefore (a) candidate tumor-suppressor gene(s), a deletion map of chromosome 16 was made, using 10 microsatellite markers on 150 sporadic breast tumors. The 3 smallest regions of overlap (SRO) were detected on the long arm of chromosome 16. Allelic imbalance was observed with at least one marker in 67% of the tumors. One marker, D16S421, at the 16q22-23 region, showed the highest allelic imbalance, 58%. Tumors with and without AI on 16q were tested for correlation with clinico-pathological features of the tumors such as estrogen- and progesterone-receptor content (ER and PgR), age at diagnosis, tumor size, node status, histological type, S-phase fraction, AI on chromosome 3p, and ploidy. A correlation was found between AI on 16q and high PgR content, also low S-phase fraction (99% confidence limits). A comparison of tumors with and without AI at the D16S421 marker locus revealed a slight correlation with high PgR content. The survival data showed no difference between patients with AI on 16q and those with a normal allele pattern on the long arm of chromosome 16.
Skirnisdottir
S
S
Department of Pathology, University and National Hospital of Iceland, Reykjavik.
Eiriksdottir
G
G
Baldursson
T
T
Barkardottir
R B
RB
Egilsson
V
V
Ingvarrson
S
S
D000483:Alleles; D001483:Base Sequence; D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism*; D002872:Chromosome Deletion; D002874:Chromosome Mapping; D002885:Chromosomes, Human, Pair 16; D004273:DNA, Neoplasm / Q000235:genetics; D006579:Heterozygote; D006801:Humans; D008875:Middle Aged; D008969:Molecular Sequence Data; D015999:Multivariate Analysis; D016133:Polymerase Chain Reaction; D016016:Proportional Hazards Models; D011980:Receptors, Progesterone / Q000032:analysis*; D016196:S Phase; D016019:Survival Analysis
D004273:DNA, Neoplasm; D011980:Receptors, Progesterone