Resistance to Ara-C up-regulates the activation of NF-kappaB, telomerase activity and Fas expression in NALM-6 cells.

Cytosine arabinoside (1-beta-D-arabinofuranosylcytosine; Ara-C) is the most important antimetabolite used to induce remission in acute leukemia, but cellular resistance to Ara-C reflects a poor prognosis in cancer chemotherapy. To further investigate the mechanisms of resistance to Ara-C, we have established Ara-C-resistant NALM-6 cells. The activation of nuclear factor kappaB (NF-kappaB) was accompanied by the acquisition of Ara-C resistance.

Inhibitory effect of naringin on lipopolysaccharide (LPS)-induced endotoxin shock in mice and nitric oxide production in RAW 264.7 macrophages.

Lipopolysaccharide (LPS) has been known to induce endotoxin shock via production of inflammatory modulators such as tumor necrosis factor alpha (TNF-alpha), or nitric oxide (NO). In this study, we have examined the effect of naringin (NG), one of the flavonoids, on LPS-induced endotoxin shock in mice and NO production in RAW 264.7 macrophages.

Inhibitory effects of naringenin on tumor growth in human cancer cell lines and sarcoma S-180-implanted mice.

We have investigated the effect of naringenin (NGEN) on tumor growth in various human cancer cell lines and sarcoma S-180-implanted mice. NGEN showed cytotoxicity in cell lines derived from cancer of the breast (MCF-7, MDA-MB-231), stomach (KATOIII, MKN-7), liver (HepG2, Hep3B, Huh7), cervix (Hela, Hela-TG), pancreas (PK-1), and colon (Caco-2) as well as leukemia (HL-60, NALM-6, Jurkat, U937). NGEN-induced cytotoxicity was low in Caco-2 and high in leukemia cells compared to other cell lines.

Susceptibility to cytosine arabinoside (Ara-C)-induced cytotoxicity in human leukemia cell lines.

Cytosine arabinoside (1-beta-d-arabinofuranosylcytosine; Ara-C) is the most important antimetabolite chemotherapeutic drug used for acute leukemia. We examined the difference in susceptibility to Ara-C-induced cell death among a number of typical human leukemia cell lines, NALM-6, MOLT-4, Jurkat, U937 and HL-60. NALM-6, which had a high expression level of p53, a tumor suppressor gene, was most susceptible to Ara-C.

Effects of naringin on cytosine arabinoside (Ara-C)-induced cytotoxicity and apoptosis in P388 cells.

Naringin (NG), a flavonoid in grapefruit and citrus, has been reported to exhibit antioxidant effects and pharmacological actions. Recently, we have reported that NG suppressed the cytotoxicity and apoptosis induced by H(2)O(2), a typical pro-oxidant, in mouse leukemia P388 cells. Cytosine arabinoside (1-beta-d-arabinofuranosylcytosine; Ara-C) is the most important antimetabolite chemotherapeutic drug used for acute leukemia.

Diethyldithiocarbamate-induced cytotoxicity and apoptosis in leukemia cell lines.

Diethyldithiocarbamate (DDTC) has been shown to induce cytotoxicity in several different systems. We examined whether the DDTC-induced cytotoxicity was via apoptosis, or in relation to intracellular glutathione (GSH) in various murine and human leukemia cell lines. The cells most sensitive to DDTC-induced cytotoxicity were P388 lymphoid neoplasma cells and NALM-6, a B cell line of acute lymphocytic leukemia (ALL).

Effects of naringin on hydrogen peroxide-induced cytotoxicity and apoptosis in P388 cells.

Flavonoids are widely recognized as naturally occurring antioxidants. Naringin (NG) is one of the flavonoid components in citrus fruits such as grapefruit. Hydrogen peroxide (H2O2) causes cytotoxicity through oxidative stress and apoptosis.