The omega-hydroxy palmitic acid induced apoptosis in human lung carcinoma cell lines H596 and A549.
We have found that omega-hydroxy palmitic acid (16-hydroxy palmitic acid, omega-HPA) has both cell growth inhibiting and cell death inducing actions on human lung adenosquamous carcinoma cell line H596 and adenocarcinoma cell line A549. Further, these effects were dose- and time-dependent in both cell lines. However, in squamous carcinoma cell line H226, omega-HPA had no cytotoxic effect. On the other hand, in the human small cell lung carcinoma (SCLC) cell line H128, this compound showed weak cytotoxicity. The sensitivity toward omega-HPA was higher in H596 cells than in A549 cells. In both H596 and A549 cells, cell growth was inhibited to 24.4 and 9.4%, respectively, by treatment with 100 microM omega-HPA for 12 h. In the 24 h treatment cells, growth inhibition was increased to 100 and 38.1%, respectively. In cytotoxicity experiments, the number of dead cells increased with incubation times in the presence of omega-HPA: on three days incubation with 100 microM omega-HPA, viability was 0 and 13.5%, respectively, in H596 and A549 cells. Further, the fragmentation of DNA to oligonucleosomal-sized ladder fragments, which is an index of apoptosis, was observed in both cell lines on treatment with omega-HPA. Therefore, it is assumed that these cell deaths induced by omega-HPA, were apoptosis in these cell lines. Since the number of dead cells following treatment with omega-HPA decreased by treatment with omega-HPA in combination with Z-VAD-fmk, a caspase family inhibitor, it is thought that apoptotic cell death was related to caspase activity.
Department of Biochemistry, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, Japan. aabe-bc@tokyo-med.ac.jp
Akihisa
A
Abe
Mototeru
M
Yamane
Hiroyuki
H
Yamada
Isamu
I
Sugawara
D000230:Adenocarcinoma / Q000188:drug therapy / Q000473:pathology; D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D000972:Antineoplastic Agents, Phytogenic / Q000627:therapeutic use*; D017209:Apoptosis; D002277:Carcinoma / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology; D018196:Carcinoma, Adenosquamous / Q000188:drug therapy / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000473:pathology; D061945:Caspase Inhibitors; D002455:Cell Division; D002460:Cell Line; D002470:Cell Survival; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D053938:DNA Fragmentation / Q000187:drug effects; D004273:DNA, Neoplasm / Q000648:ultrastructure; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology; D010169:Palmitic Acids / Q000627:therapeutic use*; D013997:Time Factors; D014407:Tumor Cells, Cultured
D000590:Amino Acid Chloromethyl Ketones; D000972:Antineoplastic Agents, Phytogenic; D061945:Caspase Inhibitors; D015853:Cysteine Proteinase Inhibitors; D004273:DNA, Neoplasm; D010169:Palmitic Acids; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; C063407:16-hydroxypalmitic acid