Effect of polyamine deficiency on proteins involved in Okazaki fragment maturation.
Polyamine depletion causes S phase prolongation, and earlier studies indicate that the elongation step of DNA replication is affected. This led us to investigate the effects of polyamine depletion on enzymes crucial for Okazaki fragment maturation in the two breast cancer cell lines MCF-7 and L56Br-C1. In MCF-7 cells, treatment with N(1),N(11)-diethylnorspermine (DENSPM) causes S phase prolongation. In L56Br-C1 cells the prolongation is followed by massive apoptosis. In the present study we show that L56Br-C1 cells have substantially lower basal expressions of two Okazaki fragment maturation key proteins, DNA ligase I and FEN1, than MCF-7 cells. Thus, these two proteins might be promising markers for prediction of polyamine depletion sensitivity, something that can be useful for cancer treatment with polyamine analogues. DENSPM treatment affects the cellular distribution of FEN1 in L56Br-C1 cells, but not in MCF-7 cells, implying that FEN1 is affected by or involved in DENSPM-induced apoptosis.
Johansson
Veronica M
VM
Department of Cell and Organism Biology, Lund University, Helgonavägen 3B, SE-223 62 Lund, Sweden. veronica.johansson@cob.lu.se
Miniotis
Maria Falck
MF
Hegardt
Cecilia
C
Jönsson
Göran
G
Staaf
Johan
J
Berntsson
Pia S H
PS
Oredsson
Stina M
SM
Alm
Kersti
K
D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics; D014408:Biomarkers, Tumor / Q000032:analysis / Q000378:metabolism; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism; D002277:Carcinoma / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D004247:DNA / Q000378:metabolism*; D000072481:DNA Ligase ATP; D011088:DNA Ligases / Q000378:metabolism*; D004261:DNA Replication / Q000235:genetics*; D019008:Drug Resistance, Neoplasm / Q000187:drug effects / Q000235:genetics; D045585:Flap Endonucleases / Q000378:metabolism*; D006801:Humans; D011073:Polyamines / Q000819:agonists / Q000378:metabolism*; D016196:S Phase / Q000235:genetics*; D013096:Spermine / Q000031:analogs & derivatives / Q000494:pharmacology / Q000627:therapeutic use
D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; C000607892:LIG1 protein, human; C022262:Okazaki fragments; D011073:Polyamines; C059685:N(1),N(11)-diethylnorspermine; D013096:Spermine; D004247:DNA; D045585:Flap Endonucleases; C468317:FEN1 protein, human; D011088:DNA Ligases; D000072481:DNA Ligase ATP