The identification of two germ-line mutations in the human breast cancer resistance protein gene that result in the expression of a low/non-functional protein

Sho Yoshioka, Kazuhiro Katayama, Chikako Okawa, Sachiko Takahashi, Satomi Tsukahara, Junko Mitsuhashi, Yoshikazu Sugimoto

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

Purpose. We examined the effects of the nine nonsynonymous germ-line mutations/SNPs in the breast cancer resistance protein (BCRP/ABCG2) gene on the expression and function of the protein. Materials and Methods. We generated cDNAs for each of these mutants (G151T, C458T, C496G, A616C, T623C, T742C, T1291C, A1768T, and G1858A BCRP) and compared the effects of their exogenous expression in PA317 cells with a wild-type control. Results. PA/F208S cells (T623C BCRP-transfectants) expressed marginal levels of a BCRP protein species (65kDa), which is slightly smaller than wild-type (70kDa), but this mutant did not appear on the cell surface or confer drug resistance. PA/F431L cells (T1291C BCRP-transfectants) were found to express both 70kDa and 65kDa BCRP protein products. In addition, although PA/F431L cells expressed 70kDa BCRP at comparable levels to PA/WT cells, they showed only marginal resistance to SN-38. PA/T153M cells (C458T BCRP-transfectants) and PA/D620N cells (G1858A BCRP-transfectants) expressed lower amounts of BCRP and showed lower levels of resistance to SN-38 compared with PA/WT cells. Conclusions. We have shown that T623C BCRP encodes a non-functional BCRP and that T1291C BCRP encodes a low-functional BCRP. Hence, these mutations may affect the pharmacokinetics of BCRP substrates in patients harboring these alleles.

Original languageEnglish
Pages (from-to)1108-1117
Number of pages10
JournalPharmaceutical Research
Volume24
Issue number6
DOIs
Publication statusPublished - 2007 Jun

Fingerprint

irinotecan
Germ-Line Mutation
Genes
Proteins
Pharmacokinetics
Complementary DNA
human ABCG2 protein
Substrates
Pharmaceutical Preparations
Drug Resistance
Single Nucleotide Polymorphism
Alleles
Breast Neoplasms
Gene Expression
Mutation

Keywords

  • BCRP/ABCG2
  • Drug resistance
  • SN-38
  • SNPs

ASJC Scopus subject areas

  • Chemistry(all)
  • Pharmaceutical Science
  • Pharmacology

Cite this

The identification of two germ-line mutations in the human breast cancer resistance protein gene that result in the expression of a low/non-functional protein. / Yoshioka, Sho; Katayama, Kazuhiro; Okawa, Chikako; Takahashi, Sachiko; Tsukahara, Satomi; Mitsuhashi, Junko; Sugimoto, Yoshikazu.

In: Pharmaceutical Research, Vol. 24, No. 6, 06.2007, p. 1108-1117.

Research output: Contribution to journalArticle

Yoshioka, Sho ; Katayama, Kazuhiro ; Okawa, Chikako ; Takahashi, Sachiko ; Tsukahara, Satomi ; Mitsuhashi, Junko ; Sugimoto, Yoshikazu. / The identification of two germ-line mutations in the human breast cancer resistance protein gene that result in the expression of a low/non-functional protein. In: Pharmaceutical Research. 2007 ; Vol. 24, No. 6. pp. 1108-1117.
@article{be1edc72864c4d65acc6d242edb430a2,
title = "The identification of two germ-line mutations in the human breast cancer resistance protein gene that result in the expression of a low/non-functional protein",
abstract = "Purpose. We examined the effects of the nine nonsynonymous germ-line mutations/SNPs in the breast cancer resistance protein (BCRP/ABCG2) gene on the expression and function of the protein. Materials and Methods. We generated cDNAs for each of these mutants (G151T, C458T, C496G, A616C, T623C, T742C, T1291C, A1768T, and G1858A BCRP) and compared the effects of their exogenous expression in PA317 cells with a wild-type control. Results. PA/F208S cells (T623C BCRP-transfectants) expressed marginal levels of a BCRP protein species (65kDa), which is slightly smaller than wild-type (70kDa), but this mutant did not appear on the cell surface or confer drug resistance. PA/F431L cells (T1291C BCRP-transfectants) were found to express both 70kDa and 65kDa BCRP protein products. In addition, although PA/F431L cells expressed 70kDa BCRP at comparable levels to PA/WT cells, they showed only marginal resistance to SN-38. PA/T153M cells (C458T BCRP-transfectants) and PA/D620N cells (G1858A BCRP-transfectants) expressed lower amounts of BCRP and showed lower levels of resistance to SN-38 compared with PA/WT cells. Conclusions. We have shown that T623C BCRP encodes a non-functional BCRP and that T1291C BCRP encodes a low-functional BCRP. Hence, these mutations may affect the pharmacokinetics of BCRP substrates in patients harboring these alleles.",
keywords = "BCRP/ABCG2, Drug resistance, SN-38, SNPs",
author = "Sho Yoshioka and Kazuhiro Katayama and Chikako Okawa and Sachiko Takahashi and Satomi Tsukahara and Junko Mitsuhashi and Yoshikazu Sugimoto",
year = "2007",
month = "6",
doi = "10.1007/s11095-007-9235-2",
language = "English",
volume = "24",
pages = "1108--1117",
journal = "Pharmaceutical Research",
issn = "0724-8741",
publisher = "Springer New York",
number = "6",

}

TY - JOUR

T1 - The identification of two germ-line mutations in the human breast cancer resistance protein gene that result in the expression of a low/non-functional protein

AU - Yoshioka, Sho

AU - Katayama, Kazuhiro

AU - Okawa, Chikako

AU - Takahashi, Sachiko

AU - Tsukahara, Satomi

AU - Mitsuhashi, Junko

AU - Sugimoto, Yoshikazu

PY - 2007/6

Y1 - 2007/6

N2 - Purpose. We examined the effects of the nine nonsynonymous germ-line mutations/SNPs in the breast cancer resistance protein (BCRP/ABCG2) gene on the expression and function of the protein. Materials and Methods. We generated cDNAs for each of these mutants (G151T, C458T, C496G, A616C, T623C, T742C, T1291C, A1768T, and G1858A BCRP) and compared the effects of their exogenous expression in PA317 cells with a wild-type control. Results. PA/F208S cells (T623C BCRP-transfectants) expressed marginal levels of a BCRP protein species (65kDa), which is slightly smaller than wild-type (70kDa), but this mutant did not appear on the cell surface or confer drug resistance. PA/F431L cells (T1291C BCRP-transfectants) were found to express both 70kDa and 65kDa BCRP protein products. In addition, although PA/F431L cells expressed 70kDa BCRP at comparable levels to PA/WT cells, they showed only marginal resistance to SN-38. PA/T153M cells (C458T BCRP-transfectants) and PA/D620N cells (G1858A BCRP-transfectants) expressed lower amounts of BCRP and showed lower levels of resistance to SN-38 compared with PA/WT cells. Conclusions. We have shown that T623C BCRP encodes a non-functional BCRP and that T1291C BCRP encodes a low-functional BCRP. Hence, these mutations may affect the pharmacokinetics of BCRP substrates in patients harboring these alleles.

AB - Purpose. We examined the effects of the nine nonsynonymous germ-line mutations/SNPs in the breast cancer resistance protein (BCRP/ABCG2) gene on the expression and function of the protein. Materials and Methods. We generated cDNAs for each of these mutants (G151T, C458T, C496G, A616C, T623C, T742C, T1291C, A1768T, and G1858A BCRP) and compared the effects of their exogenous expression in PA317 cells with a wild-type control. Results. PA/F208S cells (T623C BCRP-transfectants) expressed marginal levels of a BCRP protein species (65kDa), which is slightly smaller than wild-type (70kDa), but this mutant did not appear on the cell surface or confer drug resistance. PA/F431L cells (T1291C BCRP-transfectants) were found to express both 70kDa and 65kDa BCRP protein products. In addition, although PA/F431L cells expressed 70kDa BCRP at comparable levels to PA/WT cells, they showed only marginal resistance to SN-38. PA/T153M cells (C458T BCRP-transfectants) and PA/D620N cells (G1858A BCRP-transfectants) expressed lower amounts of BCRP and showed lower levels of resistance to SN-38 compared with PA/WT cells. Conclusions. We have shown that T623C BCRP encodes a non-functional BCRP and that T1291C BCRP encodes a low-functional BCRP. Hence, these mutations may affect the pharmacokinetics of BCRP substrates in patients harboring these alleles.

KW - BCRP/ABCG2

KW - Drug resistance

KW - SN-38

KW - SNPs

UR - http://www.scopus.com/inward/record.url?scp=34249080047&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34249080047&partnerID=8YFLogxK

U2 - 10.1007/s11095-007-9235-2

DO - 10.1007/s11095-007-9235-2

M3 - Article

C2 - 17373578

AN - SCOPUS:34249080047

VL - 24

SP - 1108

EP - 1117

JO - Pharmaceutical Research

JF - Pharmaceutical Research

SN - 0724-8741

IS - 6

ER -