Breast cyst fluids increase the proliferation of breast cell lines in correlation with their hormone and growth factor concentration.
OBJECTIVE
Gross cystic disease (GCD) of the breast is reported to occur in 7% of women in the developed world and, although not premalignant, is thought to be associated with an increased risk of breast cancer. Hormone and growth factor concentration levels were measured in breast cyst fluid (BCF) to correlate them with their mitogenic activity in tumour (MCF-7) or nontransformed (MCF-10A) cells.


RESULTS
Oestradiol (E2), oestrone (E1), E2-sulfate (E2-S), E1-sulfate (E1-S) and epidermal growth factor (EGF) concentrations were, as expected, significantly higher in type I than in type II cysts, while transforming growth factor-beta 2 (TGF-beta2) showed higher levels in type II cysts. Fifty per cent of the BCF samples stimulated [3H]-thymidine incorporation into MCF-7 cells while 34.5% inhibited this parameter. In MCF-10A cells, most BCF samples were stimulatory (85%). E2, E1 and EGF concentrations in BCF samples correlated significantly and positively with cell proliferation in MCF-7 cells, whereas a significant negative correlation was found for TGF-beta2. In MCF-10A cells, only E2-S and E1-S exhibited significant positive correlation, whereas a significant negative correlation was found for TGF-beta2. Progesterone (Pg), E2 and EGF incubated under the same conditions had a stimulatory effect on [3H]-thymidine incorporation into MCF-7 cells, whereas TGF-beta2 inhibited this parameter. Pg, E2, E1 and EGF significantly stimulated this parameter in MCF-10A cells.


CONCLUSIONS
The stimulatory action of BCF on cell proliferation in a model of human breast epithelial cells could partly explain the increased incidence of breast cancer in cyst-bearing women.
Enriori
Pablo J
PJ
Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina.
Vázquez
Stella Maris
SM
Chiauzzi
Violeta
V
Pérez
Cecilia
C
Fischer
Carlos R
CR
Gori
Jorge R
JR
Etkin
Alberto E
AE
Charreau
Eduardo
E
Calandra
Ricardo S
RS
Lüthy
Isabel A
IA
D000328:Adult; D001826:Body Fluids / Q000737:chemistry / Q000378:metabolism; D047688:Breast Cyst / Q000378:metabolism*; D045744:Cell Line, Tumor / Q000378:metabolism / Q000473:pathology*; D049109:Cell Proliferation; D004815:Epidermal Growth Factor / Q000032:analysis; D004847:Epithelial Cells / Q000473:pathology; D005260:Female; D013006:Growth Hormone / Q000378:metabolism*; D006728:Hormones / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000032:analysis; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D011188:Potassium / Q000032:analysis; D012964:Sodium / Q000032:analysis; D016212:Transforming Growth Factor beta / Q000032:analysis
D006728:Hormones; D018972:Insulin-Like Growth Factor Binding Protein 3; D016212:Transforming Growth Factor beta; D004815:Epidermal Growth Factor; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; D012964:Sodium; D011188:Potassium