Impact of MAGE-A antigens on taxane response in oral squamous cell carcinoma

Abstract

MAGE-A antigens are a subgroup of cancer/testis antigens that are exclusively expressed in malignant cells. Only scarce information on the function of MAGE-A antigens is available. There is some evidence that they may influence the response to chemotherapeutic drugs. This study aimed to evaluate the impact of the MAGE-A antigen subgroups MAGE-A2, -A3, -A4 and -A6 on oral squamous cell carcinoma cell lines treated with docetaxel and paclitaxel. Five oral squamous cell carcinoma cell lines were characterized for their quantitative expression of MAGE-A2, -A3, -A4 and -A6. The cell lines were treated with concentrations ranging from 0.025 to 0.8 μM of docetaxel and paclitaxel. The amount of viable cells after 24 and 48 h was measured. The measurements were statistically correlated with MAGE-A expression. All cell lines responded to docetaxel and paclitaxel. One cell line showed a statistically significant weaker response to the taxane treatment. This cell line was the only one that expressed MAGE-A4. MAGE-A4 has a statistically significant impact on the tumour response to docetaxel and paclitaxel in oral squamous cell carcinoma. This may influence treatment options and the course of the disease. Therefore, patients should be evaluated for MAGE-A4 expression before treatment with taxanes.

Figure 1

Exponential decrease of viable cells at different concentrations of docetaxel within 24 h; x-axis, increasing concentrations of docetaxel in μM and y-axis, percentage of viable cells.

Figure 2

Exponential decrease of viable cells at different concentrations of docetaxel within 48 h. Of note is the significantly lower decrease of viable cells in the cell line PCI 52; x-axis, increasing concentrations of docetaxel in μM and y-axis, percentage of viable cells.

Figure 3

The relatively homogeneous distribution of cell decrease between the cell lines. No cell line significantly differed in the number of viable cells after 24 h of paclitaxel application; x-axis, increasing concentrations of paclitaxel in μM and y-axis, percentage of viable cells.

Figure 4

Significantly reduced decrease of viable cells within 48 h of paclitaxel incubation. The decrease at 0.8 μM was less than half of the next most viable cell line (PCI 68-1); x-axis, increasing concentrations of paclitaxel in μM and y-axis, percentage of viable cells.