Suppression of tumorigenesis by the breast cancer cell line MCF-7 following transfer of a normal human chromosome 11.
Breast cancer development is associated with several genetic abnormalities. Loss of heterozygosity in the short arm of chromosome 11 has been observed in 30% of tumors. We found homozygosity at five chromosome 11 polymorphic loci in genomic DNA of the MCF-7 breast carcinoma cell line, suggesting a possible loss of one chromosome 11. We have studied the transformed and tumorigenic phenotypes of MCF-7 cells following introduction of a normal human chromosome 11 via microcell fusion. MCF-7/H11 cell hybrids, containing chromosome 11, showed in vitro characteristics similar to the parental cell line. However, tumorigenicity in athymic mice was completely suppressed. Since tumor formation by MCF-7 cells is estrogen dependent, we have analysed the expression of the estrogen receptor and of the estrogen-activated gene pS2. No difference was detected between the parental MCF-7 cells and the derived chromosome 11 cell hybrids, indicating that the mechanism of MCF-7 tumor suppression by chromosome 11-associated functions does not directly involve the estrogen/estrogen receptor molecular pathway.
Negrini
M
M
Interdepartment Centre for Cancer Research, University of Ferrara, Italy.
Castagnoli
A
A
Sabbioni
S
S
Recanatini
E
E
Giovannini
G
G
Possati
L
L
Stanbridge
E J
EJ
Nenci
I
I
Barbanti-Brodano
G
G
D000818:Animals; D001943:Breast Neoplasms / Q000235:genetics*; D002460:Cell Line; D002869:Chromosome Aberrations; D002880:Chromosomes, Human, Pair 11; D005260:Female; D016147:Genes, Tumor Suppressor; D006801:Humans; D006822:Hybrid Cells; D008325:Mammary Neoplasms, Experimental / Q000517:prevention & control*; D051379:Mice; D009368:Neoplasm Transplantation; D010641:Phenotype; D011960:Receptors, Estrogen / Q000032:analysis; D014162:Transfection; D014183:Transplantation, Heterologous; D014407:Tumor Cells, Cultured
D011960:Receptors, Estrogen