Chromium VI-induced apoptosis in a human bronchial epithelial cell line (BEAS-2B) and a lymphoblastic leukemia cell line (MOLT-4).
Hexavalent chromium compounds are well-documented human carcinogens. In vitro experiments show Cr (VI) induces cell death by apoptosis by activating p53 protein. The aim of this study was to evaluate Cr (VI)-induced apoptosis in a human bronchial epithelial cell line (BEAS-2B) and in a lymphoblastic leukemia cell line (MOLT-4). Cr (VI) caused a dose- and time-dependent increase in the apoptosis rate in both cell lines. Western blotting showed increased p53 protein expression in MOLT-4 cells, but not in BEAS-2B cells, after exposure to 0.5 and 3 muM hexavalent chromium for 12 hours and 4 hours, respectively. Apoptotic cell death induced by Cr (VI) was not decreased by pretreatment with caspase-3, -8, and -9 inhibitors. These preliminary results provide evidence of Cr (VI)-induced apoptosis, which deserves further investigation in occupationally exposed workers.
Department of Clinical and Experimental Medicine, Division of Occupational Medicine, University of Perugia, Perugia, Italy.
Angela
A
Gambelunghe
Renza
R
Piccinini
Giuseppe
G
Abbritti
Maura
M
Ambrogi
Barbara
B
Ugolini
Cristina
C
Marchetti
Graziella
G
Migliorati
Chiara
C
Balducci
Giacomo
G
Muzi
D017209:Apoptosis; D002274:Carcinogens, Environmental / Q000009:adverse effects*; D061945:Caspase Inhibitors; D002460:Cell Line; D045744:Cell Line, Tumor; D002857:Chromium / Q000009:adverse effects*; D004249:DNA Damage; D006801:Humans; D007945:Leukemia, Lymphoid; D020545:Respiratory Mucosa; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
D002274:Carcinogens, Environmental; D061945:Caspase Inhibitors; D016159:Tumor Suppressor Protein p53; D002857:Chromium; C074702:chromium hexavalent ion