Expression of MUCI splice variants correlates with invasive growth of breast cancer cell lines.
On the basis of alternative splicing the human breast cancer associated MUCI gene codes for different protein products. MUCI splice variants A and B have been shown to be determined by a single A/G nucleotide polymorphism (SNP) in exon 2 of the MUCI gene. We now describe two new splice variants C and D and show by that in human breast cancer cell lines there is selective co-expression of these variants, namely co-expression of variants A and D. We have found that the expression of variants C and D is also determined by the same SNP in exon 2. Since the overexpression of MUCI proteins has been associated with increased invasive behavior of cancer cell lines, we quantitatively determined the mRNA expression levels of the splice variants A, B, C, and D in breast cancer cell lines and correlated them with the in vitro invasiveness of these cell lines. We revealed a significant correlation between the lack of MUCI splice variants B and C and the invasiveness of the cell lines tested. Furthermore, we showed that concomitant expression of variants A and D is associated with a GG in the genotype. These findings suggest that the invasive behavior of breast cell lines may depend on different expression patterns of the MUCI gene determined by a genetic polymorphism.
Schmid
Bernd C
BC
Molecular Oncology Group, Division of Gynecology, Department of Obstetrics and Gynecology, University of Vienna, Vienna, Austria.
Buluwela
Laki
L
Liu
QiuYan
Q
Fasching
Barbara
B
Tong
Dan
D
Stimpfl
Margit
M
Andreas
Obermair
O
Leodolter
Sepp
S
Zeillinger
Robert
R
D017398:Alternative Splicing; D001483:Base Sequence; D001943:Breast Neoplasms / Q000235:genetics*; D002455:Cell Division; D002999:Clone Cells / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D014644:Genetic Variation; D006801:Humans; D008969:Molecular Sequence Data; D018396:Mucin-1 / Q000235:genetics*; D009361:Neoplasm Invasiveness / Q000235:genetics*; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D011995:Recombination, Genetic / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured / Q000166:cytology
D018396:Mucin-1; D020033:Protein Isoforms