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Docetaxel induced gene expression patterns in head and neck squamous cell carcinoma using cDNA microarray and
George H Yoo1, Marie P Piechocki, John F Ensley
1Department of Otolaryngology-Head and Neck Surgery, Wayne State University and Karmanos Cancer Institute, Detroit, Michigan 48201, USA.
Purpose:
The purpose is to identify gene expression patterns induced by docetaxelin head and neck squamous carcinoma (HNSCC) cells using high throughput techniques.
Experimental Design:
HNSCC cells were treated with docetaxel or solvent. After mRNA extraction, cDNA fluorescent (Cy3 or Cy5)-labeled probes were synthesized. Then, Cy3 and Cy5-labeled samples were hybridized onto a microarray slide. The fluorescent images were scanned and analyzed for quantification. PowerBlot immunoblotting technique was used to measure protein expression level. Using this dual approach, we focused on genes in established pathways (cell cycle, apoptosis, angiogenesis, and signal transduction) of tumorigenesis and confirmed these results with conventional techniques.
Results:
Using cDNA microarray, we found that docetaxel altered the expression of >100 genes in HNSCC cells. A total of 153 of 1191 genes was found to have altered expression in either HN12 (n = 102), HN30 (n = 72), or both (n = 21) by docetaxel. For the PowerBlot analysis, a subset of genes (n = 46) in the cDNA microarray analysis and an additional 98 genes in the cell cycle, apoptosis, angiogenesis, and signal transduction pathways were chosen. We found that PowerBlot data agreed with cDNA microarray in 65% of genes examined. The expression of a cell cycle inhibitor (p19) and promoters (cyclin A, cyclin B1, and cyclin E2F) were increased and decreased, respectively. Apoptosis induced by docetaxel was independent of p53 and, in part, related to increased Fas expression. Both vascular endothelial growth factor secretion and basic fibroblast growth factor expression were inhibited by docetaxel, whereas thrombospondin-1 expression was increased by docetaxel. Epidermal growth factor receptor, activated epidermal growth factor receptor, and activated c-Jun NH(2)-terminal kinase expression was lowered by docetaxel. Activated extracellular signal-regulated kinase was elevated by docetaxel, but not total extracellular signal-regulated kinase levels.
Conclusions:
The identification of altered gene expression induced by docetaxel demonstrates additional biological activity in HNSCC cells, and the altered expression of these genes may serve as potential biomarkers to both predict clinical activity and provide information regarding potential efficacy of adding novel agents.
Insights
Docetaxel alters gene expression in head and neck squamous cell carcinoma (HNSCC) cells, affecting cell cycle, apoptosis, and angiogenesis pathways. These gene expression changes may predict treatment response and guide the use of new therapies.
Area of Science:
- Oncology
- Molecular Biology
- Genomics
Background:
- Head and neck squamous cell carcinoma (HNSCC) is a significant global health concern.
- Docetaxel is a chemotherapy agent used in various cancers, but its precise molecular effects in HNSCC require further elucidation.
Purpose of the Study:
- To identify gene expression patterns induced by docetaxel in HNSCC cells.
- To investigate the impact of docetaxel on key tumorigenesis pathways including cell cycle, apoptosis, angiogenesis, and signal transduction.
Main Methods:
- Utilized cDNA microarray and PowerBlot immunoblotting techniques for high-throughput gene and protein expression analysis.
- Focused on genes within established cancer-related pathways.
- Confirmed findings using conventional molecular biology techniques.
Main Results:
- Docetaxel altered the expression of over 100 genes in HNSCC cells.
- Identified specific changes in cell cycle regulators (e.g., increased p19, decreased cyclins), apoptosis markers (e.g., increased Fas, p53-independent), angiogenesis factors (e.g., inhibited VEGF, increased thrombospondin-1), and signal transduction molecules (e.g., decreased EGFR, altered ERK/JNK activity).
- PowerBlot analysis confirmed cDNA microarray results for 65% of examined genes.
Conclusions:
- Docetaxel exhibits significant biological activity in HNSCC cells, altering multiple gene expression pathways.
- The identified docetaxel-induced gene expression alterations may serve as potential biomarkers for predicting clinical response.
- These findings provide insights into the efficacy of docetaxel and potential combination therapies.