Breast cancer. Cyr61 is overexpressed, estrogen-inducible, and associated with more advanced disease.
To identify genes involved in breast cancer, polymerase chain reaction-selected cDNA subtraction was utilized to construct a breast cancer-subtracted library. Differential screening of the library isolated the growth factor-inducible immediate-early gene Cyr61, a secreted, cysteine-rich, heparin binding protein that promotes endothelial cell adhesion, migration, and neovascularization. Northern analysis revealed that Cyr61 was expressed highly in the invasive breast cancer cell lines MDA-MB-231, T47D, and MDA-MB-157; very low levels were found in the less tumorigenic MCF-7 and BT-20 breast cancer cells and barely detectable amounts were expressed in the normal breast cells, MCF-12A. Univariate analysis showed a significant or borderline significant association between Cyr61 expression and stage, tumor size, lymph node positivity, age, and estrogen receptor levels. Interestingly, expression of Cyr61 mRNA increased 8- to 12-fold in MCF-12A and 3- to 5-fold in MCF-7 cells after 24- and 48-h exposure to estrogen, respectively. Induction of Cyr61 mRNA was blocked by tamoxifen and ICI182,780, inhibitors of the estrogen receptor. Stable expression of Cyr61 cDNA under the regulation of a constitutive promoter in MCF-7 cells enhanced anchorage-independent cell growth in soft agar and significantly increased tumorigenicity and vascularization of these tumors in nude mice. Moreover, overexpression of Cyr61 in MCF-12A normal breast cells induced their tumor formation and vascularization in nude mice. In summary, these results suggest that Cyr61 may play a role in the progression of breast cancer and may be involved in estrogen-mediated tumor development.
Xie
D
D
Division of Hematology/Oncology, Cedars-Sinai Medical Center, University of California, Los Angeles 90048, USA. xied@ucla.edu
Miller
C W
CW
O'Kelly
J
J
Nakachi
K
K
Sakashita
A
A
Said
J W
JW
Gornbein
J
J
Koeffler
H P
HP
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D018931:Antineoplastic Agents, Hormonal / Q000494:pharmacology; D015152:Blotting, Northern; D001943:Breast Neoplasms / Q000098:blood supply / Q000188:drug therapy / Q000378:metabolism*; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism / Q000473:pathology; D002465:Cell Movement; D002478:Cells, Cultured; D055515:Cysteine-Rich Protein 61; D018076:DNA, Complementary / Q000378:metabolism; D018450:Disease Progression; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology; D004965:Estrogen Antagonists / Q000494:pharmacology; D004967:Estrogens / Q000378:metabolism*; D005260:Female; D000077267:Fulvestrant; D015723:Gene Library; D006133:Growth Substances / Q000096:biosynthesis*; D006801:Humans; D017874:Immediate-Early Proteins / Q000096:biosynthesis*; D036341:Intercellular Signaling Peptides and Proteins; D051379:Mice; D008819:Mice, Nude; D008875:Middle Aged; D015999:Multivariate Analysis; D009368:Neoplasm Transplantation; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011960:Receptors, Estrogen / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013629:Tamoxifen / Q000494:pharmacology; D013997:Time Factors; D014162:Transfection; D014407:Tumor Cells, Cultured
D018931:Antineoplastic Agents, Hormonal; C501848:CCN1 protein, human; C491850:CCN1 protein, mouse; D055515:Cysteine-Rich Protein 61; D018076:DNA, Complementary; D004965:Estrogen Antagonists; D004967:Estrogens; D006133:Growth Substances; D017874:Immediate-Early Proteins; D036341:Intercellular Signaling Peptides and Proteins; D011960:Receptors, Estrogen; D011994:Recombinant Proteins; D013629:Tamoxifen; D000077267:Fulvestrant; D004958:Estradiol