MicroRNA profiling of peripheral blood enriched for circulating tumor cells (CTCs) in testicular germ cell tumors (TGCTs).

TL;DR: MicroRNA profiling of peripheral blood enriched for circulating tumor cells (CTCs) in testicular germ cell tumors (TGCTs) identifies potential treatment resistance signature.

Abstract: 4556 Background: CTCs are prognostic in several types of tumors and are easily accessible for repeat examination. TGCTs represent a model for the cure of cancer. Nonetheless, a small proportion of patients develop disease recurrence. We investigated expression profiling of PB enriched for CTCs in TGCTs aimed to identify expression signature associated with treatment resistance. Methods: This prospective study included 30 patients (pt) treated with first line (27 pt) or salvage (3 pt) chemotherapy. CD45- peripheral mononuclear cells (PBMCs) were isolated from 10mL of PB on day 1 and on day 22 of first cycle of chemotherapy. Isolated PBMC were depleted of cells of hematopoietic origin (CD45+) using RossetteSep kit negative selection with anti-CD45 antibody. CD45-depleted PBMC represent compartment enriched for CTCs, as showed previously. RNA was extracted from CD45-PBMCs and the expression profiles were obtained using Roche NimbleGen microarrays. Data analysis was processed in R using a limma package follow...