Abstract
Analysis of gene expression using RNA from the paraffin-embedded tissues is becoming an important way to study cancer pathogenesis. In this article, total RNA was extracted from tissue of 158 cases of paraffin-embedded tongue cancer, and expression of angiopoietin-like 4, tenascin-C and cathepsin-C were detected by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Our results demonstrated that high expression level of angiopoietin-like 4 or tenascin-C was predictive of poor prognosis of tongue cancer patients (p = 0.024 and p = 0.011, respectively), especially when expression levels of both genes were concomitantly high (p = 0.001). Additionally, high expression of angiopoietin-like 4 and tenascin-C, or concomitant high expression of angiopoietin-like 4 and tenascin-C were independent prognostic factors of poor survival in patients with tongue cancer. These results suggest that the improved method of RNA extraction is suitable for analysing gene expression of paraffin-embedded solid tumours. Angiopoietin-like 4 and tenascin-C, especially the combination of angiopoietin-like 4 and tenascin-C, are useful for predicting the prognosis of the patients with tongue cancer, independent of lymph node metastasis status.
Acknowledgements
We would like to thank Professor Yuming Wen for critical comments on the manuscript. This work was supported by China National Science Foundation grant to Pan Jian, Li Longjiang (contract grant number 30400505, 30471093, and 39700162).
Declaration of interest: The authors report no conflict of interests. The authors alone are responsible for the content and writing of the paper.