Characterizing genetic transitions of copy number alterations and allelic imbalances in metastatic process of the oral tongue carcinoma

Primary tumor heterogeneity can significantly affect the genetic profile of clones at metastatic sites. In order to understand the mechanisms underlying metastasis, we compared the genetic profile of paired primary tumor (PT) and metastatic lymph node (MLN) samples obtained from individual patients. Large-scale genetic profiling was performed on paired PT-MLN tissue samples obtained from 10 oral tongue squamous cell carcinoma (OTSCC) patients using high-density single-nucleotide polymorphism microarrays. We compared the genetic profile of PT and MLN OTSCC samples from the same patient in order to identify common and specific copy number alterations (CNAs) and copy-neutral loss of heterozygosity (CN-LOH).