Specific lipoplex-mediated antisense against Bcl-2 in breast cancer cells: a comparison between different formulations.

G3139 is an antisense oligonucleotide (ODN) that can down-regulate bcl-2, thus potentially acting as a potent anticancer drug. However, effective therapy requires efficient ODN delivery, which may be achieved by employing G3139 lipoplexes. Yet, lipofection is a complex, multifactorial process that is still poorly understood.

P53 in cytoplasm may enhance the accuracy of DNA synthesis by human immunodeficiency virus type 1 reverse transcriptase.

The tumor suppressor protein p53 displays 3' --> 5' exonuclease activity and can provide a proofreading function for DNA polymerases. Reverse transcriptase (RT) of human immunodeficiency virus (HIV)-1 is responsible for the conversion of the viral genomic ssRNA into the proviral DNA in the cytoplasm. The relatively low fidelity of HIV-1 RT was implicated as a dominant factor contributing to the genetic variability of the virus.

p53-associated 3'-->5' exonuclease activity in nuclear and cytoplasmic compartments of cells.

The tumor suppressor protein p53 plays an important role in maintenance of the genomic integrity of cells. p53 possesses an intrinsic 3'-->5' exonuclease activity. p53 was found in the nucleus and in the cytoplasm of the cell.

Altered subcellular localization of p53 in estrogen-dependent and estrogen-independent breast cancer cells.

LCC2, an estradiol-independent tamoxifen (Tax)-resistant subline of MCF-7 human breast cancer cell line, is resistant relatively towards Tax and methotrexate (Mtx). The purpose of the present study is to evaluate the role of p53 in determining this resistance. While MCF-7 is sensitive to and undergoes apoptosis, as determined by propidium iodide stain, by Tax and Mtx, LCC2 is resistant to apoptosis induction by these agents.