NTRK3 and neoplasm: To determine whether the loss or gain of TrkC expression could affect primary tumor formation in vivo, we injected SNU387 cells expressing TrkC shRNA or TrkC-expressing PLC/PRF/5 cells into the mouse and observed that tumors arising from SNU387 TrkC-shRNA cells had significantly reduced in size and tumor growth relative to those arising from its control cells (Fig. 3A, B).