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MCF‐7 breast cancer cells grown as multicellular spheroids in vitro : Effect of 17β‐estradiol
Author(s) -
Olea Nicolás,
Villalobos Mercedes,
De Almodóvar J. Mariano Ruiz,
Pedraza Vicente
Publication year - 1992
Publication title -
international journal of cancer
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.475
H-Index - 234
eISSN - 1097-0215
pISSN - 0020-7136
DOI - 10.1002/ijc.2910500123
Subject(s) - spheroid , in vitro , chemistry , cancer cell , cell , biophysics , estrogen receptor , cell growth , biology , cancer , microbiology and biotechnology , biochemistry , breast cancer , genetics
To obtain multicellular spheroids from MCF‐7 human breast cancer cells we adhered to the following procedure: (a) limiting the adherence of cell to the substratum; (b) seeding more than the minimum number of cells; (c) guaranteeing the presence of estrogens in the culture medium. Charcoal‐dextran (CO)‐ treated sera seemed to inhibit spheroid formation. A reduction in the concentration of CD‐human sera (from 10% to 5%) added to phenol‐red‐free medium facilitated progress from cellular aggregates to multicellular spheroids. Once the spheroids became initiated, size increased at a rate that showed a good fit to a Gompertzian equation (A = 0.368 ± 0.067 α = 0.065 ± 0.013, r range = 0.890–0.989). Three different patterns of spheroid morphology and proliferative kinetic were defined: (a) spheroids with diameter < 200 μm had a constant pattern of heterogeneity in the distribution of 3 H‐TdR‐labelled cells and in the expression of estrogen receptors; (b) spheroids 250 to 700 μm in diameter showed a decrease in the proportion of 3 H‐TdR‐labelled cells accompanying inward progression (50% in the outer shell, less than 10% in a cell layer located at a depth of 150 μm) while, at a depth of 170 μm, of signs of concurrent cellular degeneration and death were apparent; and (c) spheroids with a diameter of > 750 μm showed a crust of viable cells uniformly labelled with thymidine without impairment of the proportion of labelled cells when progressing inward from the spheroid crust. The larger the spheroid volume, the lower its growth fraction and the longer its volume doubling time. The hormone‐dependence of MCF‐7 cells in forming multicellular spheroids represents a unique experimental model for assessing estrogen action on cell organization and proliferation.