title: Isolation of a stromal cell line from an early passage of a mouse mammary tumor line: a model for stromal parenchymal interactions.
abstract: We have developed a murine mammary tumor cell line, MC4-L4, and after 15 passages, a spindle-shaped population became evident. The cuboidal cells, MC4-L4E, cloned by limit dilution, proved to be epithelial tumor cells. When inoculated in syngeneic mice, they gave rise to invasive metastatic carcinomas expressing estrogen and progesterone receptors. These tumors regressed after anti-progestin treatment and stopped growing after 17-beta-estradiol administration. In vitro, they were insensitive to medroxyprogesterone acetate (MPA), 17-beta-estradiol, and EGF and were inhibited by TGFbeta1. They expressed mutated p53 and estrogen receptors alpha; progesterone receptors were undetectable. Cells were polyploid and shared the same four common marker chromosomes present in the parental tumor in addition to an exclusive marker. Spindle-shaped cells, MC4-L4F, were selected by differential attachment and detachment and proved to be non-epithelial non-tumorigenic cells. They were cytokeratin negative, showed mesenchymal features by electron microscopy, differentiated to adipocytes when treated with an adipogenic cocktail, were stimulated by TGFbeta1 and EGF, showed a wild-type p53, and did not exhibit the marker chromosomes of the parental tumor. Although they expressed estrogen receptors alpha, they were insensitive to 17-beta-estradiol in proliferation assays. Co-cultures of both cell types had a synergic effect on progesterone receptors expression and on cell proliferation, being the epithelial cells, the most responsive ones, and 17-beta-estradiol increased cell proliferation only in co-cultures. Cytogenetic studies and data on p53 mutations rule out the possibility of an epithelial mesenchymal transition. Their unique characteristics make them an excellent model to be used in studies of epithelial-stromal interactions in the context of hormone responsiveness in hormone related tumors.
authors.affiliation: Instituto de Biología y Medicina Experimental (Consejo Nacional de Investigaciones Científicas y Técnicas, CONICET), Buenos Aires, Argentina.
authors.forename: Caroline A
authors.initials: CA
authors.lastname: Lamb
authors.forename: Victoria
authors.initials: V
authors.lastname: Fabris
authors.forename: María Alicia
authors.initials: MA
authors.lastname: Gorostiaga
authors.forename: Luisa A
authors.initials: LA
authors.lastname: Helguero
authors.forename: Alejo
authors.initials: A
authors.lastname: Efeyan
authors.forename: María Cecilia
authors.initials: MC
authors.lastname: Bottino
authors.forename: Marina
authors.initials: M
authors.lastname: Simian
authors.forename: Rocío
authors.initials: R
authors.lastname: Soldati
authors.forename: Norberto
authors.initials: N
authors.lastname: Sanjuan
authors.forename: Alfredo
authors.initials: A
authors.lastname: Molinolo
authors.forename: Claudia
authors.initials: C
authors.lastname: Lanari
mesh_terms: D000818:Animals; D018931:Antineoplastic Agents, Hormonal / Q000378:metabolism; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology; D018929:Cell Culture Techniques / Q000379:methods; D002454:Cell Differentiation; D045744:Cell Line, Tumor / Q000166:cytology / Q000502:physiology; D048430:Cell Shape; D018920:Coculture Techniques; D004815:Epidermal Growth Factor / Q000378:metabolism; D004958:Estradiol / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D005819:Genetic Markers; D006727:Hormone Antagonists / Q000378:metabolism; D006801:Humans; D007633:Keratins / Q000378:metabolism; D008321:Mammary Glands, Animal / Q000166:cytology*; D017258:Medroxyprogesterone Acetate / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D015735:Mifepristone / Q000378:metabolism; D009154:Mutation; D009368:Neoplasm Transplantation; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D017154:Stromal Cells / Q000166:cytology / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000378:metabolism; D053773:Transforming Growth Factor beta1; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism
chemical_list: D018931:Antineoplastic Agents, Hormonal; D005819:Genetic Markers; D006727:Hormone Antagonists; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508960:TGFB1 protein, human; C508961:Tgfb1 protein, mouse; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D016159:Tumor Suppressor Protein p53; D015735:Mifepristone; D004958:Estradiol; D004815:Epidermal Growth Factor; D007633:Keratins; D017258:Medroxyprogesterone Acetate