The cytotoxic prodigiosin induces phosphorylation of p38-MAPK but not of SAPK/JNK.
Prodigiosin (PG) is a red pigment produced by Serratia marcescens, with cytotoxic and immunosuppressive activity. It induces apoptosis in several cancer cell lines, including Jurkat-T cells. Here we examine the role of two stress-stimulated kinase cascades in this induction. Time course experiments using polyclonal antibodies showed that p38-MAPK phosphorylation began at 15 min and lasted for 3 h, whereas JNK was not phosphorylated, although both proteins were present. SB203580, a selective inhibitor of p38-MAPK, blocked its phosphorylation in PG-treated cells. Taken together, these data suggest that the PG induces phosphorylation of p38-MAPK but not of SAPK/JNK and that it increases the expression of both c-jun and c-fos oncoproteins.
Montaner
Beatriz
B
Cancer Cell Biology Research Group, Departament de Biologia Cellular i Anatomia Patològica, Universitat de Barcelona, Pavelló Central, 5a planta, LR 5.1, C/Feixa Llarga s/n, E-08907 L'Hospitalet, Barcelona, Spain.
Pérez-Tomás
Ricardo
R
D000903:Antibiotics, Antineoplastic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases; D019169:Jurkat Cells; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D011353:Prodigiosin / Q000494:pharmacology*; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis; D016755:Proto-Oncogene Proteins c-jun / Q000096:biosynthesis; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D048051:p38 Mitogen-Activated Protein Kinases
D000903:Antibiotics, Antineoplastic; D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D013755:Tetradecanoylphorbol Acetate; D011353:Prodigiosin