pr200935y_si_002.pdf (2.68 MB)
Biomarkers of Breast Cancer Apoptosis Induced by Chemotherapy and TRAIL
journal contribution
posted on 2016-02-22, 07:11 authored by Sharon Leong, Matthew
J. McKay, Richard I. Christopherson, Robert C. BaxterTreatment of breast cancer is complex and challenging
due to the
heterogeneity of the disease. To avoid significant toxicity and adverse
side-effects of chemotherapy in patients who respond poorly, biomarkers
predicting therapeutic response are essential. This study has utilized
a proteomic approach integrating 2D-DIGE, LC–MS/MS, and bioinformatics
to analyze the proteome of breast cancer (ZR-75-1 and MDA-MB-231)
and breast epithelial (MCF-10A) cell lines induced to undergo apoptosis
using a combination of doxorubicin and TRAIL administered in sequence
(Dox-TRAIL). Apoptosis induction was confirmed using a caspase-3 activity
assay. Comparative proteomic analysis between whole cell lysates of
Dox-TRAIL and control samples revealed 56 differentially expressed
spots (≥2-fold change and p < 0.05) common
to at least two cell lines. Of these, 19 proteins were identified
yielding 11 unique protein identities: CFL1, EIF5A, HNRNPK, KRT8,
KRT18, LMNA, MYH9, NACA, RPLP0, RPLP2, and RAD23B. A subset of the
identified proteins was validated by selected reaction monitoring
(SRM) and Western blotting. Pathway analysis revealed that the differentially
abundant proteins were associated with cell death, cellular organization,
integrin-linked kinase signaling, and actin cytoskeleton signaling
pathways. The 2D-DIGE analysis has yielded candidate biomarkers of
response to treatment in breast cancer cell models. Their clinical
utility will depend on validation using patient breast biopsies pre-
and post-treatment with anticancer drugs.