Cigarette smoke condensate-induced transformation of normal human breast epithelial cells in vitro.
In the present study, we showed that a single-dose treatment of normal breast epithelial cell line, MCF10A, for 72 h with cigarette smoke condensate (CSC) resulted in a transformed phenotype. The anchorage-dependent growth of these cells was decreased due to increased cell cycle arrest in S-G2/M phase; however, the surviving cells developed resistance due to an increased Bcl-xL to Bax ratio. Levels of PCNA and gadd45 proteins--involved in DNA repair in response to genomic damage--were increased, suggesting that the cells were responding to CSC-induced genomic damage. The transformation of MCF10A cells was determined by their colony-forming efficiency in soft-agar in an anchorage-independent manner. CSC-treated MCF10A cells efficiently formed colonies in soft-agar. We then re-established cell lines from the soft-agar colonies and further examined the persistence of their transforming characteristics. The re-established cell lines, when plated after 17 passages without CSC treatment, still formed colonies in the soft-agar. An increased staining of neuropilin-1 (NRP-1) further showed a transformation characteristic of MCF10A cells treated with CSC. In summary, our results suggest that CSC is capable of transforming the MCF10A cells in vitro, supporting the role of cigarette smoking and increased risk for breast cancer.
Narayan
Satya
S
Department of Anatomy and Cell Biology, UF Shands Cancer Center, Academic Research Building, Room R4-216, PO Box 100232, University of Florida, Gainesville, FL 32610, USA. snarayan@ufscc.ufl.edu
Jaiswal
Aruna S
AS
Kang
Diana
D
Srivastava
Pratima
P
Das
Gokul M
GM
Gairola
C Gary
CG
D001940:Breast / Q000473:pathology*; D001943:Breast Neoplasms / Q000209:etiology*; D002455:Cell Division; D002471:Cell Transformation, Neoplastic; D004249:DNA Damage; D004847:Epithelial Cells / Q000473:pathology; D005260:Female; D006801:Humans; D020104:Immunophilins / Q000032:analysis; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D011518:Proto-Oncogene Proteins / Q000032:analysis; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis; D012906:Smoke / Q000009:adverse effects*; D014026:Nicotiana; D051028:bcl-2-Associated X Protein; D051020:bcl-X Protein
C494826:BAX protein, human; C494811:BCL2L1 protein, human; D018809:Proliferating Cell Nuclear Antigen; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D012906:Smoke; D051028:bcl-2-Associated X Protein; D051020:bcl-X Protein; D020104:Immunophilins