Nuclear translocation of the p65 subunit of NF-kappa B in L5178Y sublines differing in antioxidant defense

We examined the induction of nuclear translocation of the p65 subunit of NF -kappa B in L5178Y (LY) cells. We used two LY sublines which are inversely cross-sensitive to hydrogen peroxide and x-rays: LY-R cells are radioresist ant and oxidant-sensitive, whereas LY-S cells are radiosensitive and oxidan t-resistant. Hydrogen peroxide, phorbol ester and x-rays caused a marked tr anslocation of p65-NF-kappa B in LY-R cells and a weak translocation in LY- S cells. By manipulating the antioxidant defense status, we obtained an alt eration in the p65-NF-kappa B translocation induction in LY-R cells. A simi lar effect was achieved with lovastatin pretreatment (25 mu M, 24 h, 37 deg rees C). The response of LY-S cells under all these conditions was consider ably weaker. We conclude that differential nuclear translocation of p65-NF- kappa B in LY sublines is not related to the lethal effect of the activatin g, damaging agent; rather it is due to the more efficient antioxidant defen se in LY-S than in LY-R cells.