Abstract
Previously we identified 65 radioresistant marker associated with heterogeneity in radioresistance among human tumor cell lines (The 49th annual meeting of the JRRS) (K. Ishikawa et.al., Int J Radiat Oncol Biol Phys. 2006). We have analyzed the expression of these markers in cervical cancers treated by radiotherapy.
Tumor samples were obtained from 25 patients with squamous cell carcinoma of the uterine cervix, before and during fractionated radiotherapy. Alterations in gene expression were analyzed by oligonucleotide microarray experiments (Codelink, GE Healthcare). When we applied the genes identified as radioresistant markers into clustering analysis of the patients, they were effective in separating the poor responders (local recurrence at 6 months or 1 year following radiotherapy) from good responders (complete remission at 6 months or 1 year). We found that in the poor responders there was a tendency for the genes expressed lower in the radioresistant cultured cells to be further suppressed, while those expressed at higher levels in the radiosensitive cultured cells were further induced in the good responders. Some genes harboring extra cellular matrix were included in this clustering.
Our data suggested that the radioresistant marker produced from in vitro would be useful for clinical analyses. This result gives some support to the application of in vitro analysis to in vivo analysis.
