TY - JOUR
T1 - Peloruside- and laulimalide-resistant human ovarian carcinoma cells have βI-tubulin mutations and altered expression of βII- and βIII-tubulin isotypes
AU - Kanakkanthara, Arun
AU - Wilmes, Anja
AU - O'Brate, Aurora
AU - Escuin, Daniel
AU - Chan, Ariane
AU - Gjyrezi, Ada
AU - Crawford, Janet
AU - Rawson, Pisana
AU - Kivell, Bronwyn
AU - Northcote, Peter T.
AU - Hamel, Ernest
AU - Giannakakou, Paraskevi
AU - Miller, John H.
PY - 2011/8
Y1 - 2011/8
N2 - Peloruside A and laulimalide are potent microtubule-stabilizing natural products with a mechanism of action similar to that of paclitaxel. However, the binding site of peloruside A and laulimalide on tubulin remains poorly understood. Drug resistance in anticancer treatment is a serious problem. We developed peloruside A- and laulimalide-resistant cell lines by selecting 1A9 human ovarian carcinoma cells that were able to grow in the presence of one of these agents. The 1A9-laulimalide resistant cells (L4) were 39-fold resistant to the selecting agent and 39-fold cross-resistant to peloruside A, whereas the 1A9-peloruside A resistant cells (R1) were 6-fold resistant to the selecting agent while they remained sensitive to laulimalide. Neither cell line showed resistance to paclitaxel or other drugs that bind to the taxoid site on b-tubulin nor was there resistance to microtubule-destabilizing drugs. The resistant cells exhibited impaired peloruside A/ laulimalide-induced tubulin polymerization and impaired mitotic arrest. Tubulin mutations were found in the bI-tubulin isotype, R306H or R306C for L4 and A296T for R1 cells. This is the first cell-based evidence to support a b-tubulin-binding site for peloruside A and laulimalide. To determine whether the different resistance phenotypes of the cells were attributable to any other tubulin alterations, the b-tubulin isotype composition of the cells was examined. Increased expression of bII- and bIII-tubulin was observed in L4 cells only. These results provide insight into how alterations in tubulin lead to unique resistance profiles for two drugs, pelorusideAand laulimalide, that have a similar mode of action.
AB - Peloruside A and laulimalide are potent microtubule-stabilizing natural products with a mechanism of action similar to that of paclitaxel. However, the binding site of peloruside A and laulimalide on tubulin remains poorly understood. Drug resistance in anticancer treatment is a serious problem. We developed peloruside A- and laulimalide-resistant cell lines by selecting 1A9 human ovarian carcinoma cells that were able to grow in the presence of one of these agents. The 1A9-laulimalide resistant cells (L4) were 39-fold resistant to the selecting agent and 39-fold cross-resistant to peloruside A, whereas the 1A9-peloruside A resistant cells (R1) were 6-fold resistant to the selecting agent while they remained sensitive to laulimalide. Neither cell line showed resistance to paclitaxel or other drugs that bind to the taxoid site on b-tubulin nor was there resistance to microtubule-destabilizing drugs. The resistant cells exhibited impaired peloruside A/ laulimalide-induced tubulin polymerization and impaired mitotic arrest. Tubulin mutations were found in the bI-tubulin isotype, R306H or R306C for L4 and A296T for R1 cells. This is the first cell-based evidence to support a b-tubulin-binding site for peloruside A and laulimalide. To determine whether the different resistance phenotypes of the cells were attributable to any other tubulin alterations, the b-tubulin isotype composition of the cells was examined. Increased expression of bII- and bIII-tubulin was observed in L4 cells only. These results provide insight into how alterations in tubulin lead to unique resistance profiles for two drugs, pelorusideAand laulimalide, that have a similar mode of action.
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U2 - 10.1158/1535-7163.MCT-10-1057
DO - 10.1158/1535-7163.MCT-10-1057
M3 - Article
C2 - 21653684
AN - SCOPUS:80051599729
SN - 1535-7163
VL - 10
SP - 1419
EP - 1429
JO - Molecular cancer therapeutics
JF - Molecular cancer therapeutics
IS - 8
ER -