Mls. Mello et al., Ha-ras oncogene effect on DNA content and chromatin supraorganization in benzo[a]pyrene-transformed human breast epithelial cells, ANAL CELL P, 19(2), 1999, pp. 73-79
Citations number
22
Categorie Soggetti
Research/Laboratory Medicine & Medical Tecnology","Medical Research Diagnosis & Treatment
When transfected to benzo[a]pyrene (BP)-transformed MCF-10F human breast ep
ithelial cells (BP1 cell line) the c-Ha-ras oncogene has proven to enhance
the neoplastic changes initiated by exposure to BP, giving rise to an aggre
ssive tumorigenic cell line, BP1-Tras. We have previously demonstrated by i
mage analysis that BP affects the DNA content and the chromatin supraorgani
zation of MCF-10F cells. Here Feulgen-stained BP1-Tras cells were studied b
y image analysis in order to evaluate possible additional changes in DNA co
ntent and chromatin texture induced by insertion of the ras oncogene. A hig
h variability in DNA content also including polyploidy or near-polyploidy,
and an increase in the packing states of the chromatin which became still c
ondensed in BP1 cells were found in BP1-Tras cells. The results differed fr
om those reported for the BP1-E1 cell Line which is also an aggressive tumo
rigenic cell Line, but was attained through progressive passages of BP-tran
sformed cells. It was demonstrated that different patterns of changes in DN
A content and chromatin organization may be involved in equally aggressive
tumorigenic BP-transformed cell lines originated from the same cell line by
different mechanisms.