Gene expression profiling of oral squamous cell carcinoma using laser microdissection and cDNA microarray.

Cancer diagnosis and therapy are performed on the basis of clinical stage and clinicopathological findings; however, sensitivity to therapy and prognosis may not always be the same even when considering similar cancers because it is difficult to recognize adequate biological characteristics of a cancer when determining cancer therapy. To enable personalized medicine for cancer diagnosis and therapy, which may solve this problem, we used laser microdissection and cDNA microarrays to study the gene expression profile of oral squamous cell carcinoma. Moreover, to establish an objective evaluation with this system, we examined which type of gene expression profile corresponded to the biological characteristics of this cancer. We identified several genes that were up- or downregulated in the majority of cases and clarified genes sharing common behavioral profiles between metastasis-positive and metastasis-negative cases. It was suspected that the genes that were commonly up- or downregulated in the majority of cases were important for histogenesis and acquisition of invasion and proliferation capability and that the genes sharing common behavioral profiles between metastasis-positive and metastasis-negative cases played a large role in cancer metastasis. Using the expression profile of these genes, it may be possible to evaluate cellular state and metastatic potential and use them as tumor markers. Alternately, we showed averaged gene expression profiles in cases with or without metastasis; this may reveal a profile that could evaluate metastatic potential, which is an important element in the biological characteristics of cancer. In conclusion, our system using laser microdissection and cDNA microarray may contribute to cancer diagnosis and therapy and improvement in the quality of life of cancer patients.