A label-free mass spectrometry method for relative quantitation of β-tubulin isotype expression in human tumor tissue
Article first published online: 29 OCT 2012
© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
PROTEOMICS - Clinical Applications
Volume 6, Issue 9-10, pages 502–506, October 2012
How to Cite
Miller, L. M., Huang Yang, C.-P., Xiao, H., Isaac, S., Sève, P., Dumontet, C., Band Horwitz, S. and Hogue Angeletti, R. (2012), A label-free mass spectrometry method for relative quantitation of β-tubulin isotype expression in human tumor tissue. Prot. Clin. Appl., 6: 502–506. doi: 10.1002/prca.201200018
- Issue published online: 29 OCT 2012
- Article first published online: 29 OCT 2012
- Accepted manuscript online: 20 SEP 2012 05:41AM EST
- Manuscript Accepted: 8 AUG 2012
- Manuscript Revised: 29 JUL 2012
- Manuscript Received: 20 MAR 2012
- National Cancer Institute. Grant Number: CA 124898
- National Foundation for Cancer Research. Grant Number: NIDA5P20 DA026149
- Human lung tumors;
- Label-free quantitation;
- Mass spectrometry;
- Taxane resistance;
- β-Tubulin isotypes
Quantitation of β-tubulin isotype expression in taxane resistant human tumor tissue has been difficult to achieve because of the limited availability of validated antibodies. Here we present a label-free MS method to quantitate relative expression levels of β-tubulin isotypes.
Using isotype-specific reporter peptides, we determined relative β-tubulin isotype expression levels in human lung tumor tissue.
Four reporter peptides were chosen to quantitate the βI/βII, βIV, βIII, and βV tubulin isotypes. These peptides were validated using human cancer cell lines. The label-free method was then used to determine β-tubulin isotype expression in nine human lung tumor samples, which had been described as high or low βIII-tubulin expressing using immunohistochemistry. It was found that βI/βII (accounting for 18.7–65.7% of total β-tubulin) and βIVa/βIVb (26.3–79.1%) were the most abundant isotypes and that the βIII (0–8.9%) and βV (1.0–10.4%) were less abundant in the tissue. We also categorized the samples as high or low βIII-tubulin expressing.
Conclusion and clinical relevance
With this method we can determine the relative expression levels of β-tubulin isotypes in human tumor tissue. This method will facilitate studies assessing the use of tubulin isotypes as biomarkers of taxane resistance.