T-cell receptor repertoire in rectal cancer

Emerging evidence suggests that an increased density of pre-treatment CD8+ tumor-infiltrating lymphocytes (TILs) is associated with good response to chemoradiotherapy (CRT) in patients with locally advanced rectal cancer. However, the significance of T-cell complexity in the clinical setting remains unknown. High-throughput T-cell receptor (TCR) ß sequencing was applied to quantify the TCR repertoire of pre-treatment biopsies from 67 patients with advanced rectal cancer receiving preoperative CRT. Changes in TCR repertoire before and after CRT were also analysed in 23 patients. Overall design: T-cell receptor repertoire was analyzed using total RNA (pre-treatment: 67 samples; post-treatment: 23 samples), according to the manufacturer's instructions.