Gene expression patterns in advanced human cervical cancer

The purpose of this study was to evaluate gene expression patterns in human cervical tumors by extent of lymph node metastases at diagnosis. Pretreatment whole-body fluorodeoxyglucose-positron emission tomography (FDG-PET) imaging was performed in eight patients with invasive squamous cell carcinoma of the cervix to evaluate the extent of lymph nodes metastases. Pretreatment tumor tissue samples were subjected to laser-capture microdissection, and isolated RNA was linearly amplified and hybridized to Affymetrix Human U95A GeneChip microarrays. Molecular FDG-PET imaging revealed that three patients had lymph node involvement in the supraclavicular region and five patients did not. Microarray data were segregated into two groups based on the extent of regional lymph node involvement. Supervised clustering analysis identified 75 of about 12,000 gene transcripts represented on the array whose average expression was at least threefold different. We identified 12 of the 75 transcripts that demonstrated a statistically significant difference in expression between the two patient groups (P < 0.05). Five transcripts were upregulated and seven downregulated. Both overall and cause-specific survivals were different between these two patient groups (P= 0.006). This limited data set identified candidate biomarkers of extent of lymph node metastases that correlated with poor survival outcome.